843 resultados para Artificial satellites in search and rescue operations.
Resumo:
Drosophila Enabled (Ena) was initially identified as a dominant genetic suppressor of mutations in the Abelson tyrosine kinase and, more recently, as a member of the Ena/human vasodilator-stimulated phosphoprotein (VASP) family of proteins. We have used genetic, biochemical, and cell biological approaches to demonstrate the functional relationship between Ena and human VASP. In addition, we have defined the roles of Ena domains identified as essential for its activity in vivo. We have demonstrated that VASP rescues the embryonic lethality associated with loss of Ena function in Drosophila and have shown that Ena, like VASP, is associated with actin filaments and focal adhesions when expressed in cultured cells. To define sequences that are central to Ena function, we have characterized the molecular lesions present in two lethal ena mutant alleles that affected the Ena/VASP homology domain 1 (EVH1) and EVH2. A missense mutation that resulted in an amino acid substitution in the EVH1 domain eliminated in vitro binding of Ena to the cytoskeletal protein zyxin, a previously reported binding partner of VASP. A nonsense mutation that resulted in a C-terminally truncated Ena protein lacking the EVH2 domain failed to form multimeric complexes and exhibited reduced binding to zyxin and the Abelson Src homology 3 domain. Our analysis demonstrates that Ena and VASP are functionally homologous and defines the conserved EVH1 and EVH2 domains as central to the physiological activity of Ena.
Resumo:
The discovery of over a dozen low-mass companions to nearby stars has intensified scientific and public interest in a longer term search for habitable planets like our own. However, the nature of the detected companions, and in particular whether they resemble Jupiter in properties and origin, remains undetermined.
Resumo:
The European Union (EU) has been hailed as the most successful model of regional integration thus far, while the Association of Southeast Asian Nations (ASEAN), despite its fair share of critics and doomsayers, has been seen as a relatively successful regional organisation in the developing world. However, both seemed to have arrived at a critical juncture in their respective regional projects. Challenged by recent events, internal and external, and faced with increasing uncertainties and complexities, the EU and ASEAN are forced to re-examine the journey they have taken so far and ponder the road ahead. This paper seeks first to provide an overview of the two parallel processes of regionalism in Europe and Southeast Asia by focusing on the developments of the EU and ASEAN, and dissecting both the external forces and internal dynamics that shape the respective regional processes. It then sketches out some of the global trends likely to impact regional developments in Europe and Asia, and questions if the EU and ASEAN would need a new regional approach or paradigm if they are to maintain their salience and relevance as regional actors.
Resumo:
This paper aims to identify the Mediterranean States’ potential in adopting a regional strategy on climate change adaptation. The author proposes a Mediterranean Strategy on Adaptation to Climate Change as the first step to a political/legal regional approach to climate change issues that would supplement the multilateral process under the United Nations Framework Convention on Climate Change and the Kyoto Protocol. According to the author such a strategy would enhance cooperation between the EU and other Mediterranean states in various ways. The experience of the EU in regulating climate change and its ever growing knowledge-base on its impacts could serve to guide the other Mediterranean states’ and help bridge their knowledge-base gap on the topic. On the other hand, the support and cooperation of the EU’s Mediterranean partners would provide an opportunity for the EU to address better the challenges the climate change threatens to bring in its southernmost regions. The strategy could eventually even pave the way for the very first regional treaty on climate change that could be negotiated under the auspices of the Regional Seas Programme and the Union for the Mediterranean.
Resumo:
This Commentary warns that by continuing to act as if Turkey’s membership of the EU was still a credible prospect, the EU is dodging the critical issue of how to establish friendly and constructive relations with an independent, self-confident Turkey. More importantly, this approach prevents the EU from at last accepting that enlargement is not the only – nor necessarily the best – policy option available to deal effectively with a strategically important country on its borders.