502 resultados para Curtius Rufus, Quintus.


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We often need to estimate the size of wild populations to determine the appropriate management action, for example, to set a harvest quota. Monitoring is usually planned under the assumption that it must be carried out at fixed intervals in time, typically annually, before the harvest quota is set. However, monitoring can be very expensive, and we should weigh the cost of monitoring against the improvement that it makes in decision making. A less costly alternative to monitoring annually is to predict the population size using a population model and information from previous surveys. In this paper, the problem of monitoring frequency is posed within a decision-theory framework. We discover that a monitoring regime that varies according to the state of the system call outperform fixed-interval monitoring This idea is illustrated using data for a red kangaroo (Macropits rufus) population in South Australia. Whether or not one should monitor in a given year is dependent on the estimated population density in the previous year, the uncertainty in that population estimate, and past rainfall. We discover that monitoring is-important when a model-based prediction of population density is very uncertain. This may occur if monitoring has not taken place for several years, or if rainfall has been above average. Monitoring is also important when prior information suggests that the population is near a critical threshold in population abundance. However, monitoring is less important when the optimal management action would not be altered by new information.

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Grime Scene Investigation was an eight part television series broadcast on BBC3 during Autumn 2006. In each episode a team of scientists from Aston University would visit a member of the public in their mobile laboratory to reveal the hidden world of microbes living in, on and around them. In this way microbiology was communicated in an informative and entertaining way. In this episode, Grime Scene Investigation dives head first into the murky world of Hooligan Swamp - a Bristolian band who pride themselves on living the rock'n'roll lifestyle to the full. The Swamp are facing an eviction notice and the environmental health authorities are threatening to brand their home a health hazard.

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El trabajo se centra en el análisis de los pecados relacionados con el dinero en el Inferno de Dante y en la primera traducción castellana de la primera cantiga de la Commedia, obra del arcediano de Burgos Pedro Fernández de Villegas. La traducción, compuesta en coplas de arte mayor y acompañada de un enciclopédico comentario, se publicó en 1515. Particular atención se dedica a la reflexión sobre el problema del mal uso del dinero que Villegas desarrolla en la glosa de los cantos en que con más vigor se levanta la voz de Dante para denunciar la gravedad del pecado de la sed de riquezas. Se analiza la postura del traductor español ante el tema comparándola no sólo con la de Dante sino también con la de Cristoforo Landino, autor del Comento sopra la Comedia, obra exégetica que se publicó por primera vez en Florencia en 1481 y que representó el punto de referencia privilegiado de Villegas.

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Oxidative damage has been proposed as a potential mechanism underlying a life history tradeoff between survival and reproduction. However, evidence that reproduction is associated with increased oxidative damage is equivocal, and some studies have found that breeding females exhibit reduced, rather than elevated, levels of oxidative damage compared to equivalent non-breeders. Recently it was hypothesized that oxidative damage could have negative impacts on developing offspring, and that mothers might down-regulate oxidative damage during reproduction to shield their offspring from such damage. We tested this hypothesis through a longitudinal study of adult survival, reproduction, and oxidative damage in wild banded mongooses (Mungos mungo) in Uganda. High levels of oxidative damage as measured by malondialdehyde (MDA) were associated with reduced survival in both sexes. Levels of protein carbonyls were not linked to survival. Mothers showed reduced levels of MDA during pregnancy, and individuals with higher MDA levels gestated fewer offspring and had lower pup survival. These results suggest that maternal oxidative damage has transgenerational costs, and are consistent with the idea that mothers may attempt to shield their offspring from particularly harmful types of oxidative damage during pregnancy. We suggest that further advance in understanding of life history variation could benefit from theoretical and empirical exploration of the potential transgenerational costs of reproduction.

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Study of specimens of Merodon Meigen collected in southwestern Europe resulted in new data and taxonomic changes for this genus. The cryptic species Merodon confusus sp. nov. (Merodon equestris species group) is described based on specimens collected in Cabañeros National Park, central Spain. Morphological and molecular diagnostic characters are provided to separate members of the species group. Merodon aeneus fulvus Gil Collado is proposed as a junior synonym of Merodon pumilus Macquart. The first Iberian record of Merodon rufus Meigen is reported and updates of the revision of Iberian Merodon are provided.

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El Cerro El Potosí es un área prioritaria para la Comisión Nacional para la Biodiversidad (CONABIO) y un Área Natural Protegida por el estado (Anónimo, 2000), debido a la existencia de una gran diversidad de tipos de vegetación y de especies de importancia fitogeografica o su orografía y altitud (3715 msnm) se considera un área promotora de procesos de especiación, registrándose especies endémicas y relictuales como el caso del Pinus culminicola y Nucifraga columbiana , es una de las montañas más altas del noroeste del país, está enclavada en la Sierra Madre Oriental. Con base en la información previa disponible, se presume que esta área ostente una mayor diversidad de flora y fauna. El objetivo principal fue el análisis de la diversidad y distribución de los mamíferos en los diferentes estratos vegetativos y altitudes dentro de los límites del Cerro El Potosí. Con el propósito de realizar las comparaciones de las diversidades de las especies en forma altitudinal, por vegetación, estacional; Se seleccionó la prueba de Chi-cuadrada para determinar dependencia entre especies y la altitud, tipo de muestreo o tipo de vegetación. Se efectuaron 24 salidas (mensuales) de campo, de noviembre del 2006 a octubre del 2008, de 3 a 4 días por salida. Se registraron 27 especies (14 Familias, 24 géneros, 27 especies, y 14 especies no reportadas previamente). De acuerdo al tipo de vegetación la riqueza se concentro en el bosque de pino seguido por el bosque de encino, las especies se distribuyeron en uno, en dos o más estratos de vegetación (patrones), para los diferentes tipos de vegetación se distribuyeron las especies de Silvilagus floridanus, Thomomys bottae, Peromyscus melanotis, Peromyscus levipes ambiguus, Canis latrans y Lynx rufus. Las especies que sólo se encontraron en un solo tipo de vegetación fueron Bassariscus astutus, Conepatus mesoleucus, Corynorhinus townsendii, Didelphis virginiana, Eptesicus fuscus, Puma yagouaroundi, Lasiurus cinereus, Lasiurus ega, Leptonycteris nivalis, Mustela frenata y Sorex milleri, por lo que se aprecia la diversidad encontrada en el sitio, esto en gran medida por la asociación de la vegetación y la altura marcado por la temperatura reportada para el sitio. Las especies que se localizaron en dos o más estratos o patrones de vegetación fueron Myotis thysanodes, Sciurus alleni, Otospermophilus variegatus, Microtus mexicanus, Urocyon cinereoargenteus, Procyon lotor, Puma concolor, Pecari tajacu y Odocoileus virginianus.