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81.
82.
There is a lack of integrated knowledge on the transition to a sustainable energy system. The paper focuses on the relationship between technologies and institutions in the field of hydrogen from the perspective of political theory. The paper unfolds four paradigms of governance: ‘Governance by policy networking’, Governance by government’, ‘Governance by corporate business’, and ‘Governance by challenge’, and looks into the major line of argument in support of these paradigms and into their possible bias with respect to hydrogen options. Each of these paradigms reveals an institutional bias in that it articulates specific opportunities for collaboration and competition in order to stimulate the transition to a sustainable hydrogen economy. The paper makes the observation that there is a compelling need to reframe fashionable discourse such as the necessary shift from government to governance or from government to market. Instead, specific questions with respect to the impact of guiding policy frameworks on innovation will highlight that neither ‘neutral’ nor ‘optimal’ frameworks for policy making exist, where competing hydrogen options are at stake. The identification of paradigms of governance maybe considered a methodological device for (participator) policy analysis. 相似文献
83.
Climate is changing (WMO, Press release No. 695, 2003) and there is increasing evidence that this is due to human activity (IPCC, Climate Change 2001—The Scientific Basis, Cambridge University Press, Cambridge, 2001). One way to react is to reduce greenhouse gas emissions into the atmosphere. Although this approach generally does not cause much objection, disagreements do occur when concrete emission targets are to be set. Against this background, the following article provides an arithmetic approach for the determination of long-term emission targets where the US and the EU are studied as examples. 相似文献
84.
Michael Bode 《Fuel Cells Bulletin》2005,2005(1):12-14
85.
The functional integrity of the neuromuscular synapse requires that sufficient numbers of acetylcholinesterase (AChE) molecules be localized on the specialized extracellular matrix between the nerve terminal and the post-synaptic membrane. Multiple interrelated levels of regulation are necessary to accomplish this complex task including the spatial and temporal restriction of AChE mRNA expression within the muscle fiber, local translation and assembly of AChE polypeptides, and focused accumulation of AChE molecules on the extracellular matrix. This is accomplished in part through the organization of other extracellular matrix molecules into a complex which further associates with acetylcholine receptors and their accompanying molecules. Finally, the mature neuromuscular junction contains molecules which can act as receptors for the attachment of AChE which in turn may allow for the turnover of this enzyme at the synapse. This brief review will focus mainly on contributions from our laboratory towards understanding the mechanisms involved in organizing AChE molecules at the neuromuscular synapse. 相似文献
86.
87.
The role of the medial capsule and transverse metatarsal ligament in hallux valgus deformity including stability of the first metatarsophalangeal and adjacent joints was investigated in vitro. The three-dimensional positions of the proximal phalanx, first metatarsal, and second metatarsal before and after sectioning the medial capsule and metatarsal ligament were measured using a magnetic tracking system. Valgus deformity of the hallux increased with medial capsule sectioning an average of 22.3 degrees +/- 6 degrees. Valgus deformity of the hallux increased with medial capsule and metatarsal ligament sectioning an average of 27.4 degrees +/- 9.1 degrees. Valgus deformity of the hallux did not change significantly after sectioning the metatarsal ligament only. No significant changes were found in varus and eversion of the first metatarsal, in valgus of the second metatarsal, in the distance between first and second metatarsal heads after sectioning the medial capsule, or in the metatarsal ligament. This study shows the importance of the medial capsule in hallux valgus deformity. The transverse ligament did not contribute substantially to cause the deformity. 相似文献
88.
Huntingtin is the protein product of the gene for Huntington's disease (HD) and carries a polyglutamine repeat that is expanded in HD (>36 units). Huntingtin-associated protein (HAP1) is a neuronal protein and binds to huntingtin in association with the polyglutamine repeat. Like huntingtin, HAP1 has been found to be a cytoplasmic protein associated with membranous organelles, suggesting the existence of a protein complex including HAP1, huntingtin, and other proteins. Using the yeast two-hybrid system, we found that HAP1 also binds to dynactin P150(Glued) (P150), an accessory protein for cytoplasmic dynein that participates in microtubule-dependent retrograde transport of membranous organelles. An in vitro binding assay showed that both huntingtin and P150 selectively bound to a glutathione transferase (GST)-HAP1 fusion protein. An immunoprecipitation assay demonstrated that P150 and huntingtin coprecipitated with HAP1 from rat brain cytosol. Western blot analysis revealed that HAP1 was enriched in rat brain microtubules and comigrated with P150 and huntingtin in sucrose gradients. Immunofluorescence showed that transfected HAP1 colocalized with P150 and huntingtin in human embryonic kidney (HEK) 293 cells. We propose that HAP1, P150, and huntingtin are present in a protein complex that may participate in dynein-dynactin-associated intracellular transport. 相似文献
89.
HB Peterson 《Canadian Metallurgical Quarterly》1998,279(20):1651-1658
90.
L. M. Storozheva K. Éscher R. Bode K. Hulka D. A. Burko 《Metal Science and Heat Treatment》2002,44(3-4):102-107