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81.
The UK's vast marine energy resource is mostly located in remote areas west and north of Scotland, and transmission of this energy to the mainland will be required. This may be achieved by using this ‘stranded’ power to generate hydrogen electrolytically, which may in turn be stored or transported using sponge iron technology. This paper reviews the technology and research needed to bring such a process on stream. We propose utilising techniques that have been developed for the oxygen carriers used in chemical looping, and also those used in early processes for hydrogen generation in the chemical industry. We briefly outline the design requirements for an energy efficient sponge iron plant. It is shown that the iron sponge system presents better energy efficiencies than alternative forms of bulk storage such as liquid hydrogen, magnesium hydride slurry, some at least of the metal hydrides, or methylcyclohexane–toluene–hydrogen, provided that requirements can be met for particle durability and reactivity. 相似文献
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M Majer DM Mott H Mochizuki JC Rowles O Pedersen WC Knowler C Bogardus M Prochazka 《Canadian Metallurgical Quarterly》1996,39(3):314-321
Skeletal muscle glycogen synthase (encoded by GYS1 on chromosome 19q13.3) is the rate-limiting enzyme in insulin-mediated non-oxidative glucose disposal. Our previous studies have demonstrated an impairment of insulin-stimulated GYS1 activities in insulin-resistant Pima Indians, and associations of non-insulin-dependent diabetes mellitus (NIDDM) with the GYS1 locus were reported recently in Finnish and Japanese populations. We have performed linkage and association analyses of GYS1 and seven additional DNA markers on 19q with NIDDM, and with parameters of insulin action in the Pima Indians. We have found a significant association of NIDDM with GYS1 genotypes (p = 0.009), and with common GYS1 alleles (p = 0.022) in the Pima Indians. We have performed a detailed comparative analysis of the GYS1 gene, mRNA, and protein product in insulin-sensitive and insulin-resistant Pima Indians. No mutations in GYS1 coding sequences were detected; nor did we find alterations of GYS1 mRNA expression or of its basal enzymatic activity in insulin-resistant Pima Indians. These results contrasted with a 25% reduction of immunoreactive protein in insulin-resistant subjects as detected by Western blotting with an antibody specific for the C-terminal end of GYS1 (t-test p = 0.024; Wilcoxon's rank-sum test, p = 0.04). Because no mutations were detected in the DNA encoding this epitope, the difference in immunoreactivity may reflect post-translational modification(s) of the protein rather than a difference in the gene itself, or it could have occurred by chance. We conclude that our data do not indicate alterations in the GYS1 gene as the cause for the observed association, and that a different locus near GYS1 may be the contributing genetic element. 相似文献
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JD Belcher RC Ellison WE Shepard C Bigelow LS Webber JH Wilmore GS Parcel DM Zucker RV Luepker 《Canadian Metallurgical Quarterly》1993,22(2):143-153
Male and female isometric strength curves for elbow fixation, shoulder flexion, and wrist supination-pronation are obtained during systematic variation in arm configuration. The shape of a given moment-angle curve is found to be a function of the orientations of joints kinematically coupled to the primary joint. It is also found that female elbow strength curves are shifted toward flexion with respect to male elbow-strength curves, suggesting that the in situ rest length of upper-limb muscles relative to joint angle may be longer for males than for females. Experimental results were contrasted with simulation results obtained using a three-dimensional musculoskeletal model which estimates the relationships between initial joint orientations, muscle tension-length behavior, and joint moments. In most of the cases, simulation results complimented experimental data and provided insights into likely in situ muscle rest lengths and moments arms, especially for the multiarticular biceps brachii muscle. Where inconsistencies exist between simulated and experimental data, subtle biomechanical complexities within the forearm and the shoulder girdle complex are identified that require future investigation. 相似文献
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RD Lane DM Allan CA Bennett-Clarke DL Howell RW Rhoades 《Canadian Metallurgical Quarterly》1997,14(2):277-286
Immunocytochemistry and retrograde labeling were used to define the thalamic projections of calbindin- and parvalbumin-containing cells in superficial layers of the rat's superior colliculus (SC). Quantitative analysis revealed that 90.8 +/- 2.2% (mean +/- standard deviation) of the calbindin-immunoreactive neurons in the stratum griseum superficiale (SGS) projected to the dorsal lateral geniculate nucleus (LGNd) and that 91.3 +/- 4.3% of calbindin-immunoreactive neurons in the stratum opticum (SO) projected to the lateral posterior nucleus (LP). In contrast, only 17.3 +/- 2.5% of parvalbumin-immunoreactive neurons in the SGS were found to project to the LGNd and 16.5 +/- 3.1% of the parvalbumin-immunoreactive SO cells were retrogradely labeled after LP injections. Few of the parvalbumin-immunoreactive neurons in either the SGS (7.2 +/- 2.5%) or the SO (9.2 +/- 2.5%) were GABA positive. The retrograde-labeling results suggest that parvalbumin-immunoreactive neurons in the rat's SO and SGS may either be primarily interneurons or have descending projections, while calbindin-containing cells are primarily thalamic projection neurons. These results are consistent with data from other rodents, but almost exactly the opposite of data that have been reported for the cat for these same populations of SC projection neurons. Such interspecies differences raise questions regarding the functional importance of expressing one calcium-binding protein versus another in a specific neuronal population. 相似文献
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