883 resultados para Changing Permafrost in the Arctic and its Global Effects in the 21st Century


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Wind generated waves at the sea surface are of outstanding importance for both their practical relevance in many aspects, such as coastal erosion, protection, or safety of navigation, and for their scientific relevance in modifying fluxes at the air-sea interface. So far long-term changes in ocean wave climate have been studied mostly from a regional perspective with global dynamical studies emerging only recently. Here a global wave climate study is presented, in which a global wave model (WAM) is driven by atmospheric forcing from a global climate model (ECHAM5) for present day and potential future climate conditions represented by the IPCC (Intergovernmental Panel for Climate Change) A1B emission scenario. It is found that changes in mean and extreme wave climate towards the end of the twenty-first century are small to moderate, with the largest signals being a poleward shift in the annual mean and extreme significant wave heights in the mid-latitudes of both hemispheres, more pronounced in the Southern Hemisphere, and most likely associated with a corresponding shift in mid-latitude storm tracks. These changes are broadly consistent with results from the few studies available so far. The projected changes in the mean wave periods, associated with the changes in the wave climate in the mid to high latitudes, are also shown, revealing a moderate increase in the equatorial eastern side of the ocean basins. This study presents a step forward towards a larger ensemble of global wave climate projections required to better assess robustness and uncertainty of potential future wave climate change.

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This article presents a fresh perspective on cultural policy in revolutionary Cuba, focusing specifically on the centrality of dialogue with the general readership to the production, reception and regulation of literature. It first summarises the positions regarding revolutionary literature that have been asserted and essayed at various points along the sometimes chaotic trajectory of revolution in Cuba. It then examines reading-related policies and recent attempts within Cuba to re-orient reading practices in the aftermath of the Período Especial [Special Period], and ends by presenting current Cuban debates on the need to mitigate dialogic breakdown between literary text and readership.

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Changes in the map area of 498 glaciers located on the Main Caucasus ridge (MCR) and on Mt. Elbrus in the Greater Caucasus Mountains (Russia and Georgia) were assessed using multispectral ASTER and panchromatic Landsat imagery with 15 m spatial resolution in 1999/2001 and 2010/2012. Changes in recession rates of glacier snouts between 1987–2001 and 2001–2010 were investigated using aerial photography and ASTER imagery for a sub-sample of 44 glaciers. In total, glacier area decreased by 4.7 ± 2.1% or 19.2 ± 8.7 km2 from 407.3 ± 5.4 km2 to 388.1 ± 5.2 km2. Glaciers located in the central and western MCR lost 13.4 ± 7.3 km2 (4.7 ± 2.5%) in total or 8.5 km2 (5.0 ± 2.4%) and 4.9 km2 (4.1 ± 2.7%) respectively. Glaciers on Mt. Elbrus, although located at higher elevations, lost 5.8 ± 1.4 km2 (4.9 ± 1.2%) of their total area. The recession rates of valley glacier termini increased between 1987–2000/01 and 2000/01–2010 (2000 for the western MCR and 2001 for the central MCR and Mt.~Elbrus) from 3.8 ± 0.8, 3.2 ± 0.9 and 8.3 ± 0.8 m yr−1 to 11.9 ± 1.1, 8.7 ± 1.1 and 14.1 ± 1.1 m yr−1 in the central and western MCR and on Mt. Elbrus respectively. The highest rate of increase in glacier termini retreat was registered on the southern slope of the central MCR where it has tripled. A positive trend in summer temperatures forced glacier recession, and strong positive temperature anomalies in 1998, 2006, and 2010 contributed to the enhanced loss of ice. An increase in accumulation season precipitation observed in the northern MCR since the mid-1980s has not compensated for the effects of summer warming while the negative precipitation anomalies, observed on the southern slope of the central MCR in the 1990s, resulted in stronger glacier wastage.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Effective communication is the soul of any institution. New opportunities are presented by Information and Communication Technology (ICTS). Library managers must adopt a more critical and communication plan that will enhance their skills and allow for further training, as well as allowing stakeholders to have input into decision-making.

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The purpose of this session is to reject the notion that proactive Affirmative Action strategic plans are no longer needed at predominantly European American Institutions. Data reveal an inverse relationship between creating successful strategic plans for inclusion and negative reactions from the power structure.

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Plant extracts represent a great source of molecules, with insecticidal activity, which are used for pest control in several crop production systems. This work aimed to evaluate the toxicity of an aqueous extract of leaves of castor bean against larvae of Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) in search for different classes of molecules with insecticidal activities by using in vitro assays. The effects of the castor bean leaf extract on the food utilization, development, and survival of S. frugiperda larvae was evaluated by feeding the larvae an artificial diet supplemented with different concentrations of the extract (0%, 1%, 2.5%, 5%, and 10% w/v). The effects observed were dose-dependent, and the highest concentration evaluated (10% w/v) was the one the most affected food utilization by altering the nutritional indices, as well as larval weight gain, development time, and survivorship. In vitro assays to detect saponins, lectins, and trypsin inhibitors in the castor bean leaf extract were performed, but only trypsin inhibitors were detected. No preference for the diet source was detected in S. frugiperda by feeding the larvae in choice experiments with diets containing different concentrations of the castor bean extract tested. The data obtained indicate the existence of a potential molecule in the tested extract of castor bean to be used as an alternative insecticide to be integrated in the management of S. frugiperda.

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Objectives: The purpose of this article is to share the details, outcomes and deliverables from an international workshop on work transitions in London, Ontario, Canada. Participants: Researchers, graduate students, and community group members met to identity ways to advance the knowledge base of strategies to enhance work participation for those in the most disadvantaged groups within society. Methods: A participatory approach was used in this workshop with presentations by researchers and graduate students. This approach included dialogue and discussion with community members. In addition, small group dialogue and debate, world cafe discussions, written summaries of group discussion and reflection boards were used to bring new ideas to the discussion and to build upon what we know. Findings: Two research imperatives and six research recommendations were identified to advance global dialogue on work transitions and to advance the knowledge base. Occupational justice can be used to support future research directions in the study of work transitions. Conclusions: Moving forward requires a commitment of community of researchers, clinicians and stakeholders to address work disparities and implement solutions to promote participation in work.

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Drawing on a Polanyian analysis of the land question, this article aims to analyse both Western and Indigenous cosmologies of Abya Yalathe name that indigenous peoples give to the American continentto understand the relationship between human beings and land and nature. These cosmologies are at the heart of the way in which two distinct societies construct their regional space, one from above', the other from below', and they are therefore key to understanding today's climate change problematique. Following this nexus it is argued that, since the end of the Cold War, a new regional double-movement', unleashed by the quest for land and natural resources has been in the making. This is a superstructural or legal battle between Western transnational regime-making and a law that originated at the centre of the Earth'. The article explains both regionalisms and the dialectical interaction between them and demonstrates that Karl Polanyi's legacy remains relevant for the 21st century.