925 resultados para Thematic composition or per species and chronological composition
Resumo:
En este artículo se estudia la biografía del emperador Trajano (98-117 DC) en la Estoria de Espanna de Alfonso X (capítulos 192-95). Siguiendo ciertos principios compositivos heredados de Suetonio (ya través de Vicente de Beauvais), la semblanza se articula por 'rúbricas' descriptivas (per species) o por orden narrativo y cronológico (per temporal, dando lugar a cuatro propiedades del discurso historiográfico alfonsí: falta de datación de los hechos, anulación de los marcos temporales establecidos para cada capítulo, narratividad de varios segmentos y unificación de los mismos por sus similaridades temáticas. En base a estas categorías, se estudiarán las varias líneas argumentales de la biografía: las campañas militares de Trajano contra germanos, dacios y partos, las insurrecciones contra Roma, los desastres naturales, las relaciones con los cristianos, las anécdotas y retratos de Trajano y su muerte y vida póstuma
Resumo:
En este artículo se estudia la biografía del emperador Trajano (98-117 DC) en la Estoria de Espanna de Alfonso X (capítulos 192-95). Siguiendo ciertos principios compositivos heredados de Suetonio (ya través de Vicente de Beauvais), la semblanza se articula por 'rúbricas' descriptivas (per species) o por orden narrativo y cronológico (per temporal, dando lugar a cuatro propiedades del discurso historiográfico alfonsí: falta de datación de los hechos, anulación de los marcos temporales establecidos para cada capítulo, narratividad de varios segmentos y unificación de los mismos por sus similaridades temáticas. En base a estas categorías, se estudiarán las varias líneas argumentales de la biografía: las campañas militares de Trajano contra germanos, dacios y partos, las insurrecciones contra Roma, los desastres naturales, las relaciones con los cristianos, las anécdotas y retratos de Trajano y su muerte y vida póstuma
Resumo:
En este artículo se estudia la biografía del emperador Trajano (98-117 DC) en la Estoria de Espanna de Alfonso X (capítulos 192-95). Siguiendo ciertos principios compositivos heredados de Suetonio (ya través de Vicente de Beauvais), la semblanza se articula por 'rúbricas' descriptivas (per species) o por orden narrativo y cronológico (per temporal, dando lugar a cuatro propiedades del discurso historiográfico alfonsí: falta de datación de los hechos, anulación de los marcos temporales establecidos para cada capítulo, narratividad de varios segmentos y unificación de los mismos por sus similaridades temáticas. En base a estas categorías, se estudiarán las varias líneas argumentales de la biografía: las campañas militares de Trajano contra germanos, dacios y partos, las insurrecciones contra Roma, los desastres naturales, las relaciones con los cristianos, las anécdotas y retratos de Trajano y su muerte y vida póstuma
Resumo:
Rockfish (Sebastes spp.) biomass is difficult to assess with standard bottom trawl or acoustic surveys because of their propensity to aggregate near the seafloor in highrelief areas that are inaccessible to sampling by trawling. We compared the ability of a remotely operated vehicle (ROV), a modified bottom trawl, and a stereo drop camera system (SDC) to identify rockfish species and estimate their size composition. The ability to discriminate species was highest for the bottom trawl and lowest for the SDC. Mean lengths and size distributions varied among the gear types, although a larger number of length measurements could be collected with the bottom trawl and SDC than with the ROV. Dusky (S. variabilis), harlequin (S. variegatus), and northern rockfish (S. polyspinis), and Pacific ocean perch (S. alutus) were the species observed in greatest abundance. Only dusky and northern rockfish regularly occurred in trawlable areas, whereas these two species and many more occurred in untrawlable areas. The SDC was able to resolve the height of fish off the seafloor, and some of the rockfish species were observed only near the seafloor in the acoustic dead zone. This finding is important, in that fish found exclusively in the acoustic dead zone cannot be assessed acoustically. For these species, methods such as bottom trawls, long-lines, or optical surveys using line transect or area swept methods will be the only adequate means to estimate the abundance of these fishes. Our results suggest that the selection of appropriate methods for verifying targets will depend on the habitat types and species complexes to be examined.
Resumo:
Fish stomachs from 18 demersal and pelagic fishes from the coast of Terengganu in Malaysia were examined. The components of the fishes’ diets varied in number, weight, and their frequency of occurrence. The major food items in the stomachs of each species were determined using an Index of Relative Importance. A conceptual food web structure indicates that fish species in the study area can be classified into three predatory groups: (1) predators on largely planktivorous or pelagic species; (2) predators on largely benthophagous or demersal species; and (3) mixed feeders that consume both pelagic and demersal species.
Resumo:
The effect of poultry species (broiler or turkey) and genotype (Wrolstad or BUT T8 turkeys and Ross 308 or Cobb 500 broilers) on the efficiency with which dietary longchain n-3 PUFA were incorporated into poultry meat was determined. Broilers and turkeys of both genotypes were fed one of six diets varying in FA composition (two replicates per genotype x diet interaction). Diets contained 50 g/kg added oil, which was either blended vegetable oil (control), or partially replaced with linseed oil (20 or 40 g/kg diet), fish oil (20 or 40 g/kg diet), or a mixture of the two (20 g linseed oil and 20 g fish oil/kg diet). Feeds and samples of skinless breast and thigh meat were analyzed for FA. Wrolstad dark meat was slightly more responsive than BUT T8 (P = 0.046) to increased dietary 18:3 concentrations (slopes of 0.570 and 0.465, respectively). The Ross 308 was also slightly more responsive than the Cobb 500 (P= 0.002) in this parameter (slopes of 0.557 and 0.449). There were no other significant differences between the genotypes. There was some evidence (based on the estimates of the slopes and their associated standard errors) that white turkey meat was more responsive than white chicken meat to 20:5 (slopes of 0.504 and 0.289 for turkeys and broilers, respectively). There was no relationship between dietary 18:3 n-3 content and meat 20:5 and 22:6 contents. If birds do convert 18:3 to higher FA, these acids are not then deposited in the edible tissues.
Resumo:
Benthic foraminiferal assemblages are a widespread tool to understand changes in organic matter flux and bottom-water oxygenation and their relation to paleoceanographic changes in the Upper Cretaceous oceans. In this study, assemblage data (diversity, total number, and number per species and gram) from Deep Sea Drilling Project (DSDP) Site 390 (Blake Nose, western North Atlantic) were processed for the lower Maastrichtian (Globotruncana falsostuarti - Gansserina gansseri Planktic Foraminiferal Zone). These data document significant changes in nutrient flux to the sea floor as well as bottom-water oxygenation during this time interval. Parallel to the observed changes in the benthic foraminiferal assemblages the number of inoceramid shells decreases, reflecting also a significant increase in bottom-water oxygenation. We speculate, that these data could reflect the onset of a shift from warmer low-latitude to cooler high-latitude deep-water sources. This speculation will predate the major reorganization of the oceanic circulation resulting in a circulation mode similar to today at the Early/Late Maastrichtian boundary by ~1 Ma and therefore improves our understanding of Late Cretaceous paleoceanography.
Resumo:
Observations of hummock and string-like microrelief features were made in High Arctic hydric meadows. Thermal shearing of thick bryophyte mats, and subsequent roll back during spring flooding appears to be one way in which this topography is formed. Hummocky and non-hummocky (flat) meadows show distinct floristic differences which may in part be due to observed differences in temperature, nutrient concentrations and moisture relations.
Resumo:
The spatial and temporal dynamics of seagrasses have been studied from the leaf to patch (100 m**2) scales. However, landscape scale (> 100 km**2) seagrass population dynamics are unresolved in seagrass ecology. Previous remote sensing approaches have lacked the temporal or spatial resolution, or ecologically appropriate mapping, to fully address this issue. This paper presents a robust, semi-automated object-based image analysis approach for mapping dominant seagrass species, percentage cover and above ground biomass using a time series of field data and coincident high spatial resolution satellite imagery. The study area was a 142 km**2 shallow, clear water seagrass habitat (the Eastern Banks, Moreton Bay, Australia). Nine data sets acquired between 2004 and 2013 were used to create seagrass species and percentage cover maps through the integration of seagrass photo transect field data, and atmospherically and geometrically corrected high spatial resolution satellite image data (WorldView-2, IKONOS and Quickbird-2) using an object based image analysis approach. Biomass maps were derived using empirical models trained with in-situ above ground biomass data per seagrass species. Maps and summary plots identified inter- and intra-annual variation of seagrass species composition, percentage cover level and above ground biomass. The methods provide a rigorous approach for field and image data collection and pre-processing, a semi-automated approach to extract seagrass species and cover maps and assess accuracy, and the subsequent empirical modelling of seagrass biomass. The resultant maps provide a fundamental data set for understanding landscape scale seagrass dynamics in a shallow water environment. Our findings provide proof of concept for the use of time-series analysis of remotely sensed seagrass products for use in seagrass ecology and management.
Resumo:
Includes index.