974 resultados para 9,10-Dimetil-1,2-benzantraceno
Resumo:
Hor., en Carm., 1, 2 y 4, 15 recoge una serie de referencias a dioses importantes para la familia adoptiva de Octaviano y para el propio gobernante, que han sido tradicionalmente analizadas e interpretadas desde un punto de vista interno: su presencia se explicaría en función de su relación con la gens Iulia. El punto de vista que quiero ofrecer en mi trabajo es complementario a éste: a partir de un análisis externo de las referencias a estos dioses, creo que su presencia se puede explicar en función de los templos en los que "habitaban" en Roma, del lugar donde estos templos se encontraban y de las representaciones icónicas que servían a su culto. Al mismo tiempo, la nueva relación que establezco entre 1,2 y 4, 15 aporta evidencias para una comprensión distinta de la segunda edición de la poesía lírica de Horacio, la que se presentó con el libro 4
Resumo:
Fil: Galán, Lía Margarita. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.
Resumo:
Hor., en Carm., 1, 2 y 4, 15 recoge una serie de referencias a dioses importantes para la familia adoptiva de Octaviano y para el propio gobernante, que han sido tradicionalmente analizadas e interpretadas desde un punto de vista interno: su presencia se explicaría en función de su relación con la gens Iulia. El punto de vista que quiero ofrecer en mi trabajo es complementario a éste: a partir de un análisis externo de las referencias a estos dioses, creo que su presencia se puede explicar en función de los templos en los que "habitaban" en Roma, del lugar donde estos templos se encontraban y de las representaciones icónicas que servían a su culto. Al mismo tiempo, la nueva relación que establezco entre 1,2 y 4, 15 aporta evidencias para una comprensión distinta de la segunda edición de la poesía lírica de Horacio, la que se presentó con el libro 4
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The numbers and distributions of Peary caribou (Rangiier tarandus pearyi) on western Queen Elizabeth Islands, Northwest Territories were determined by aerial surveys based on a standard census strip method. Surveys were flown in March-April and July-August periods in 1972, 1973, and 1974. Comparison of the 1973 and 1974 survevs with those results of a comparable survey in 1961 showed an overall decline of 89% in numbers of caribou between 1961 and 1974. Percentage reduction of caribou numbers from 1961 to 1874 followed a west-cast gradient on the three major islands: Prince Patrick 72%, Melville 87% , and Bathurst 92%. The marked decrease in numbers of caribou is attributed to a combination of high winter mortality in some years and an overall low rate of births and recruitment from 1961 to 1974.
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Submarine canyon systems provide a heterogeneous habitat for deep-sea benthos in terms of topography, hydrography, and the quality and quantity of organic matter present. Enhanced meiofauna densities as found in organically enriched canyon sediments suggest that nematodes, as the dominant metazoan meiobenthic taxon, may play an important role in the benthic food web of these sediments. Very little is known about the natural diets and trophic biology of deep-sea nematodes, but enrichment experiments can shed light on nematode feeding selectivity and trophic position. An in-situ pulse-chase experiment (Feedex) was performed in the Nazaré Canyon on the Portuguese margin in summer 2007 to study nematode feeding behaviour. 13C-labelled diatoms and bacteria were added to sediment cores which were then sampled over a 14-day period. There was differential uptake by the nematode community of the food sources provided, indicating selective feeding processes. 13C isotope results revealed that selective feeding was less pronounced at the surface, compared to the sediment subsurface. This was supported by a higher trophic diversity in surface sediments compared to the subsurface, implying that more food items may be used by the nematode community at the sediment surface. Predatory and scavenging nematodes contributed relatively more to biomass than other feeding types and can be seen as key contributors to the nematode food web at the canyon site. Non-selective deposit feeding nematodes were the dominant trophic group in terms of abundance and contributed substantially to total nematode biomass. The high levels of 'fresh' (bioavailable) organic matter input and moderate hydrodynamic disturbance of the canyon environment lead to a more complex trophic structure in canyon nematode communities than that found on the open continental slope, and favours predator/scavengers and non-selective deposit feeders.
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Arctic sea ice is declining rapidly, making it vital to understand the importance of different types of sea ice for ice-dependent species such as polar bears Ursus maritimus. In this study we used GPS telemetry (25 polar bear tracks obtained in Svalbard, Norway, during spring) and high-resolution synthetic aperture radar (SAR) sea-ice data to investigate fine-scale space use by female polar bears. Space use patterns differed according to reproductive state; females with cubs of the year (COYs) had smaller home ranges and used fast-ice areas more frequently than lone females. First-passage time (FPT) analysis revealed that females with COYs displayed significantly longer FPTs near (<10 km) glacier fronts than in other fast-ice areas; lone females also increased their FPTs in such areas, but they also frequently used drifting pack ice. These results clearly demonstrate the importance of fast-ice areas, in particular close to glacier fronts, especially for females with COYs. Access to abundant and predictable prey (ringed seal pups), energy conservation and reluctance to cross large open water areas are possible reasons for the observed patterns. However, glacier fronts are retracting in Svalbard, and declines in land-fast ice have been notable over the past decade. The eventual disappearance of these important habitats might become critical for the survival of polar bear cubs in Svalbard and other regions with similar habitat characteristics. Given the relatively small size of many fast-ice areas in Svalbard, the results observed in this study would not have been revealed using less accurate location data or lower-resolution sea-ice data.