90 resultados para Social and space change
Resumo:
Ecosystem functioning in grasslands is regulated by a range of biotic and abiotic factors, and the role of microbial communities in regulating ecosystem function has been the subject of much recent scrutiny. However, there are still knowledge gaps regarding the impacts of rainfall and vegetation change upon microbial communities and the implications of these changes for ecosystem functioning. We investigated this issue using data from an experimental mesotrophic grassland study in south-east England, which had been subjected to four years of rainfall and plant functional composition manipulations. Soil respiration, nitrogen and phosphorus stocks were measured, and the abundance and community structure of soil microbes were characterised using quantitative PCR and multiplex-TRFLP analysis, respectively. Bacterial community structure was strongly related to the plant functional composition treatments, but not the rainfall treatment. However, there was a strong effect of both rainfall change and plant functional group upon bacterial abundance. There was also a weak interactive effect of the two treatments upon fungal community structure, although fungal abundance was not affected by either treatment. Next, we used a statistical approach to assess whether treatment effects on ecosystem function were regulated by the microbial community. Our results revealed that ecosystem function was influenced by the experimental treatments, but was not related to associated changes to the microbial community. Overall, these results indicate that changes in fungal and bacterial community structure and abundance play a relatively minor role in determining grassland ecosystem function responses to precipitation and plant functional composition change, and that direct effects on soil physical and chemical properties and upon plant and microbial physiology may play a more important role.
Resumo:
Kosrae, or ‘The Island of The Sleeping Lady’ as it is known to locals, is the most remote island of the Federated States of Micronesia (FSM), located in the western Pacific. FSM is an independent sovereign nation consisting of four state in total: Pohnpei, Chuuk, Yap and Kosrae. First claimed by the Spanish, who were forced to cede FSM to Germany in 1899. In 1914, the Japanese took military possession of the region resulting in considerable economic, social and political change for the islands’ inhabitants. By 1947 after WWII, the islands formed part of the Trust Territory of the Pacific Islands commissioned by the UN and administered by the US. The FSM became an independent nation in 1986 while still retaining affiliation with the US under a ‘Compact of Free Association’ encouraging the officiating of English as a language of FSM, alongside local languages. Here I examine the presence and uses of English in Kosrae with reference to these socio-historical influences. First, I discuss the extralinguistic factors which have shaped the English that is currently found on Kosrae. Secondly, I assess the use of English in this community in light of Schneider’s (2007) ‘Dynamic Model’. Finally, an overview of the salient linguistic characteristics of Kosraean English, based on data collected in informal conversations on the island, will be presented. The overall objective is to present a socio-historical, political and linguistic description of a hitherto unexamined English emerging in a postcolonial environment. Schneider, E. (2007). Postcolonial Englishes. Cambridge: Cambridge University Press. Research Interests: Global Englishes
Resumo:
Genetically encoded, ratiometric biosensors based on fluorescence resonance energy transfer (FRET) are powerful tools to study the spatiotemporal dynamics of cell signaling. However, many biosensors lack sensitivity. We present a biosensor library that contains circularly permutated mutants for both the donor and acceptor fluorophores, which alter the orientation of the dipoles and thus better accommodate structural constraints imposed by different signaling molecules while maintaining FRET efficiency. Our strategy improved the brightness and dynamic range of preexisting RhoA and extracellular signal-regulated protein kinase (ERK) biosensors. Using the improved RhoA biosensor, we found micrometer-sized zones of RhoA activity at the tip of F-actin bundles in growth cone filopodia during neurite extension, whereas RhoA was globally activated throughout collapsing growth cones. RhoA was also activated in filopodia and protruding membranes at the leading edge of motile fibroblasts. Using the improved ERK biosensor, we simultaneously measured ERK activation dynamics in multiple cells using low-magnification microscopy and performed in vivo FRET imaging in zebrafish. Thus, we provide a construction toolkit consisting of a vector set, which enables facile generation of sensitive biosensors.
Resumo:
Policies and politics are an integral part of socio-technical transitions but have not received much attention in the transitions literature so far. Drawing on the advocacy coalition framework, our paper addresses this gap with a study on actors and coalitions in Swiss energy policy. Our results show that advocacy coalitions in Switzerland have largely remained stable despite the Fukushima shock. However, heterogeneity of beliefs has increased and in 2013, even a majority of actors expressed their support for the energy transition – an indication that major policy change might be ahead. It seems that in socio-technical transitions, changes in the policy issue and in the actor base also work toward policy change, next to changes in core beliefs. We make suggestions how the advocacy coalition framework can inform analysis and theory building in transition studies. We also present first ideas about the interplay of socio-technical systems and policy systems.
Resumo:
Effective policies combating global warming and incentivising reduction of greenhouse gases face fundamental collective action problems. States defending short term interests avoid international commitments and seek to benefit from measures combating global warming taken elsewhere. The paper explores the potential of Common Concern as an emerging principle of international law, in particular international environmental law, in addressing collective action problems and the global commons. It expounds the contours of the principle, its relationship to common heritage of mankind, to shared and differentiated responsibility and to public goods. It explores its potential to provide the foundations not only for international cooperation, but also to justify, and delimitate at the same time, unilateral action at home and deploying extraterritorial effects in addressing the challenges of global warming and climate change mitigation. As unilateral measures mainly translate into measures of trade policy, the principle of Common Concern is inherently linked and limited by existing legal disciplines in particular of the law of the World Trade Organization.
Resumo:
This paper addresses the issues of dual pricing and export restrictions in the energy sector, stressing the comparability of their economic and climate change impacts. It assesses whether WTO disciplines relevant and applicable to such practices are well-equipped to ensure fair access to energy resources. It finds that relevant GATT disciplines are overall deficient in the case of dual pricing and export taxes, while the landscape of WTO-plus obligations generally consisting of a network of narrowly tailored commitments. It discusses possible avenues to address such practices under the ASCM to the extent that they distort domestic energy prices and subsidize consumption of cheap fossil fuels