(Table 2) Survivorship of transplanted seedlings of Picea glauca inside and outside three tree islands in 1994, 1995, 2009 and after 15 years

The northern boundary of boreal forest and the ranges of tree species are expected to shift northward in response to climate warming, which will result in a decrease in the albedo of areas currently covered by tundra vegetation, an increase in terrestrial carbon sequestration, and an alteration of biodiversity in the current Low Arctic. Central to the prediction of forest expansion is an increase in the reproductive capacity and establishment of individual trees. We assessed cone production, seed viability, and transplanted seedling success of Picea glauca (Moench.) Voss. (white spruce) in the early 1990s and again in the late 2000s at four forest stand sites and eight tree island sites (clonal populations beyond present treeline) in the Mackenzie Delta region of the Northwest Territories, Canada. Over the past 20 years, average temperatures in this region have increased by 0.9 °C. This area has the northernmost forest-tundra ecotone in North America and is one of the few circumpolar regions where the northern limit of conifer trees reaches the Arctic Ocean. We found that cone production and seed viability did not change between the two periods of examination and that both variables decreased northward across the forest-tundra ecotone. Nevertheless, white spruce individuals at the northern limit of the forest-tundra ecotone produced viable seeds. Furthermore, transplanted seedlings were able to survive in the northernmost sites for 15 years, but there were no signs of natural regeneration. These results indicate that if climatic conditions continue to ameliorate, reproductive output will likely increase, but seedling establishment and forest expansion within the forest-tundra of this region is unlikely to occur without the availability of suitable recruitment sites. Processes that affect the availability of recruitment sites are likely to be important elsewhere in the circumpolar ecotone, and should be incorporated into models and predictions of climate change and its effects on the northern forest-tundra ecotone.

T-388/2009. Objeción de conciencia y aborto: una perspectiva global sobre la experiencia colombiana

Disponible la versión en español y en inglés.

Crustal uplift rates of 4 GPS stations near Jakobshavn Isbrae (2006-2009)

We analyze 2006-2009 data from four continuous Global Positioning System (GPS) receivers located between 5 and 150 km from the glacier Jakobshavn Isbrae, West Greenland. The GPS stations were established on bedrock to determine the vertical crustal motion due to the unloading of ice from Jakobshavn Isbrae. All stations experienced uplift, but the uplift rate at Kangia North, only 5 km from the glacier front, was about 10 mm/yr larger than the rate at Ilulissat, located only ~45 km further away. This suggests that most of the uplift is due to the unloading of the Earth's surface as Jakobshavn thins and loses mass. Our estimate of Jakobshavn's contribution to uplift rates at Kangia North and Ilulissat are 14.6 ± 1.7 mm/yr and 4.9 ± 1.1 mm/yr, respectively. The observed rates are consistent with a glacier thinning model based on repeat altimeter surveys from NASA's Airborne Topographic Mapper (ATM), which shows that Jakobshavn lost mass at an average rate of 22 ± 2 km**3/yr between 2006 and 2009. At Kangia North and Ilulissat, the predicted uplift rates computed using thinning estimates from the ATM laser altimetry are 12.1 ± 0.9 mm/yr and 3.2 ± 0.3 mm/yr, respectively. The observed rates are slightly larger than the predicted rates. The fact that the GPS uplift rates are much larger closer to Jakobshavn than further away, and are consistent with rates inferred using the ATM-based glacier thinning model, shows that GPS measurements of crustal motion are a potentially useful method for assessing ice-mass change models.

(Table 3) Concentrations of polybrominated diphenyl ether and congeners in blubber samples from whales, seals and porpoises between 1986-2009

A selection of PBDE congeners was analyzed in pooled blubber samples of pilot whale (Globicephala melas), ringed seal (Phoca hispida), minke whale (Balaenoptera acutorostrata), fin whale (Balaenoptera physalus), harbor porpoise (Phocoena phocoena), hooded seal (Cystophora cristata) and Atlantic white-sided dolphin (Lagenorhynchus acutus), covering a time period of more than 20 years (1986-2009). The analytes were extracted and cleaned-up using open column extraction and multi-layer silica gel column chromatography, and the analysis was performed on a GC-MS system operating in the NCI mode. The highest PBDE levels were found in the toothed whale species pilot whale and white-sided dolphin, and the lowest levels in fin whales and ringed seals. One-sided analyses of variance (ANOVA) followed by Tukey comparisons of means were applied to test for differences between years and sampling areas. Due to inter-year sampling variability, only general comparisons of PBDE concentrations between different sampling areas could be made. Differences in PBDE concentrations between three sampling periods, from 1986 to 2007, were evaluated in samples of pilot whales, ringed seals, white-sided dolphins and hooded seals. The highest PBDE levels were found in samples from the late 1990s or beginning of 2000, possibly reflecting the increase in the global production of technical PBDE mixtures in the 1990s. The levels of BDE #153 and #154 increased relative to the total PBDE concentration in some of the species in recent years, which may indicate an increased relative exposure to higher brominated congeners. In order to assess the effect of measures taken in legally binding international agreements, it is important to continuously monitor POPs such as PBDEs in sub-Arctic and Arctic environments.

Una aproximación a la Responsabilidad Social Empresaria en Argentina : Caracterización de las prácticas de intervención social de las empresas adherentes al Pacto Global para el período 2008-2009

En este trabajo nos proponemos hacer una aproximación a las prácticas de Responsabilidad Social Empresaria (el adelante, RSE) llevadas adelante en Argentina por las grandes empresas suscriptas al Pacto Global (ONU) para el período 2008-2009. Fundamentalmente, nos interesa dar cuenta de la naturaleza de la intervención de las empresas en lo social. Para esto en primer lugar revisaremos el concepto de RSE, incluyendo las diferentes visiones acerca del mismo, y pensaremos el rol del Pacto Global como marco de referencia institucional de estas prácticas. En una segunda instancia, haremos una aproximación a las modalidades que adopta la RSE en Argentina analizando, entre otras cosas, las áreas de intervención, los tipos de contribución y las alianzas con otros actores (tales como ONGs, fundaciones, universidades y sector público entre otros)

La formación docente en Educación Física : Estudio sobre las elecciones de los docentes de escuelas secundarias de La Plata ante la oferta de capacitación, durante el 2007 al 2009

La pregunta que orienta la propuesta de investigación es ¿Qué lugar ocupa la participación de los docentes en el diseño las políticas de capacitación? ¿Cuáles son los aspectos que inciden en la elección de la oferta de capacitación? La intención es analizar los factores que inciden en la elección de la oferta de capacitación estatal y/o privada, que realizan los docentes del área Educación Física pertenecientes al sector estatal, que se desempeñan en escuelas medias del distrito de La Plata. Son considerados los aportes de los estudios sobre saber docente, el proceso de análisis de las políticas públicas, las regulaciones del trabajo docente y la institucionalización de ciertas modalidades de capacitación. Desde un enfoque cualitativo, la estrategia metodológica utilizará fuentes de datos orales y documentales, a través de entrevistas en profundidad y análisis de documentos que regulan la capacitación en la provincia

Uma análise sobre a produção, produtividade e colaboração na Ciência da Informação no Brasil entre os anos 2007 a 2009

This research comprises some considerations about production, productivity and scientific collaboration related to Information Science in geopolitical regions of Brazil, aiming at identifying their macro-level flow and trends. Reports were generated through identification of Information Science postgraduate programs and professors and collaborators who work on them - those reports were synthesized according to programs and regions, from the year of 2007 to 2009. We can conclude that the Southeast and Northeast regions are responsible for the higher production, productivity and collaboration indicators; we can also infer that the expansion of the relationship among different regions may offer the researchers opportunities to establish new partnerships, and to develop researches on emerging subjects in this scientific area