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71.
Raquel Santos Jorge Troy R. Hawkins Edgar G. Hertwich 《The International Journal of Life Cycle Assessment》2012,17(1):9-15
Purpose
The purpose of this study is to provide life cycle inventory data and results for components of electrical grids to the larger community of life cycle assessment practitioners. This article is the first in a series of two, each focusing on different components of power grids. In part 1, the objects under scope are power lines and cables. Systems for overhead, underground, and subsea transmission are modeled here, including HVDC systems used in long-distance transmission. 相似文献72.
G Griziotis C Hawkins A G Mackinlay R H Crozier 《Australian journal of biological sciences》1987,40(2):171-180
Mitochondrial (mt) DNAs from 17 aboriginal Australians, predominantly from the coastal region of the Northern Territory were isolated and digested with four four-base restriction endonucleases, two of which revealed variation between samples. The observed fragment patterns were used directly in parsimony analyses of phylogenetic relationships between the samples, and were also converted to estimates of the number of substitutions per nucleotide position between samples (delta), which estimates were then used in distance analyses of phylogeny. The inferred fragment patterns of the completely sequenced 'Cambridge' human mtDNA were also included in these analyses. No strong evidence of geographic variation was found, consistent with previous findings of Australian aborigines and other humans generally, although the most divergent sample was one of two from Sydney, indicating that further work is desirable. The estimate of mean difference between samples (diversity), 0.0017 +/- 0.0003 (mean +/- 95% confidence interval), is significantly lower than that reported previously for humans generally. 相似文献
73.
Hollis J. Hawkins Alan G.E. Wilson Marshall W. Anderson Thomas E. Eling 《Prostaglandins & other lipid mediators》1977,14(2):251-259
We have investigated the uptake and subsequent metabolism of the prostaglandins (PGs) PGE1, PGA1, and PGB1 by rat, guinea pig and rabbit isolated perfused lungs (IPL). Significant species differences were not observed in the uptake or metabolism of any PG on passage through the IPL. However, differences in the uptake of PGA1 and PGB1 and in the metabolism of PGA1 were observed with a given species when the composition of the perfusion medium was varied. The IPL removed minimal amounts (<20% of the supply rate) of PGA1 and PGB1 from the circulation when the perfusate contained 4.5% bovine serum albumin (BSA). In the absence of BSA, however, both PGA1 and PGB1 were substantially removed from circulation (~53% of the supply rate) and PGA1 was also metabolized. The composition of the perfusate had no effect on the uptake and metabolism of PGE1 which was always taken up and metabolized to a greater extent than was PGA1 and PGB1. Thus, the apparent species differences previously reported for the pulmonary biotransformation of PGA can result from differences in the perfusion medium used. Our data suggest that both plasma protein binding and a transport system play important roles in determining the selectivity of the uptake of PGs by the lung. 相似文献
74.
75.
Popper Arthur N. Hawkins Anthony D. Jacobs Fred Jacobson Paul T. Johnson Peter Krebs Justin 《Reviews in Fish Biology and Fisheries》2020,30(4):605-622
Reviews in Fish Biology and Fisheries - Downstream movements of some freshwater fishes, including eels, are adversely affected by the presence of hydroelectric structures and other anthropic... 相似文献
76.
Mariana Morando Luciano J. Avila Cristian H.F. Perez Monty A. Hawkins Jack W. Sites 《Molecular phylogenetics and evolution》2013,66(3):694-714
The lizard genus Phymaturus is widely distributed in Argentina and along the eastern edge of Chile between 25° and 45° south. We sampled 27 of the 38 currently recognized species plus 22 candidate species using two mitochondrial genes (cytb and 12S), four protein coding nuclear genes and seven anonymous nuclear loci, and present the first comprehensive molecular phylogenetic hypothesis for the clade. We recovered two large clades (the palluma or northern group and patagonicus or southern group) previously recognized on the basis of morphological and mitochondrial sequence evidence, and compared results obtained from concatenated-gene analyses with results of a coalescent-based species-tree approach (BEST). With both methods we identified four main clades within the palluma group (mallimaccii, roigorum, verdugo, and vociferator) and five main clades within the patagonicus group (calcogaster, indistinctus, payuniae, somuncurensis, and spurcus). We found several instances of non-monophyly with cytb and cases of incongruence between mitochondrial vs nuclear data for which we discuss alternative hypotheses. Although with lower support values, combined BEST results are more congruent with concatenated nuclear data than with combined concatenated analyses, suggesting that BEST is less influenced by demographic processes than combined concatenated analyses. We discuss the taxonomic, biogeographic and conservation implications of these results and how the future integration of phylogeographic and morphological approaches will allow the further testing of demographic and biogeographic hypotheses. 相似文献
77.
78.
Background
There is increasing recognition that the development of evidence-informed health policy is not only a technical problem of knowledge exchange or translation, but also a political challenge. Yet, while political scientists have long considered the nature of political systems, the role of institutional structures, and the political contestation of policy issues as central to understanding policy decisions, these issues remain largely unexplored by scholars of evidence-informed policy making.Methods
We conducted a systematic review of empirical studies that examined the influence of key features of political systems and institutional mechanisms on evidence use, and contextual factors that may contribute to the politicisation of health evidence. Eligible studies were identified through searches of seven health and social sciences databases, websites of relevant organisations, the British Library database, and manual searches of academic journals. Relevant findings were extracted using a uniform data extraction tool and synthesised by narrative review.Findings
56 studies were selected for inclusion. Relevant political and institutional aspects affecting the use of health evidence included the level of state centralisation and democratisation, the influence of external donors and organisations, the organisation and function of bureaucracies, and the framing of evidence in relation to social norms and values. However, our understanding of such influences remains piecemeal given the limited number of empirical analyses on this subject, the paucity of comparative works, and the limited consideration of political and institutional theory in these studies.Conclusions
This review highlights the need for a more explicit engagement with the political and institutional factors affecting the use of health evidence in decision-making. A more nuanced understanding of evidence use in health policy making requires both additional empirical studies of evidence use, and an engagement with theories and approaches beyond the current remit of public health or knowledge utilisation studies. 相似文献79.
Shaun Scholes Madhavi Bajekal Paul Norman Martin O’Flaherty Nathaniel Hawkins Mika Kivim?ki Simon Capewell Rosalind Raine 《PloS one》2013,8(7)
Aims
To estimate the number of coronary heart disease (CHD) deaths potentially preventable in England in 2020 comparing four risk factor change scenarios.Methods and Results
Using 2007 as baseline, the IMPACTSEC model was extended to estimate the potential number of CHD deaths preventable in England in 2020 by age, gender and Index of Multiple Deprivation 2007 quintiles given four risk factor change scenarios: (a) assuming recent trends will continue; (b) assuming optimal but feasible levels already achieved elsewhere; (c) an intermediate point, halfway between current and optimal levels; and (d) assuming plateauing or worsening levels, the worst case scenario. These four scenarios were compared to the baseline scenario with both risk factors and CHD mortality rates remaining at 2007 levels. This would result in approximately 97,000 CHD deaths in 2020. Assuming recent trends will continue would avert approximately 22,640 deaths (95% uncertainty interval: 20,390-24,980). There would be some 39,720 (37,120-41,900) fewer deaths in 2020 with optimal risk factor levels and 22,330 fewer (19,850-24,300) in the intermediate scenario. In the worst case scenario, 16,170 additional deaths (13,880-18,420) would occur. If optimal risk factor levels were achieved, the gap in CHD rates between the most and least deprived areas would halve with falls in systolic blood pressure, physical inactivity and total cholesterol providing the largest contributions to mortality gains.Conclusions
CHD mortality reductions of up to 45%, accompanied by significant reductions in area deprivation mortality disparities, would be possible by implementing optimal preventive policies. 相似文献80.
The K+/H+ antiporter LeNHX2 increases salt tolerance by improving K+ homeostasis in transgenic tomato 总被引:1,自引:0,他引:1
RAÚL HUERTAS LOURDES RUBIO OLIVIER CAGNAC MARÍA JESÚS GARCÍA‐SÁNCHEZ JUAN DE DIOS ALCHÉ KEES VENEMA JOSÉ ANTONIO FERNÁNDEZ MARÍA PILAR RODRÍGUEZ‐ROSALES 《Plant, cell & environment》2013,36(12):2135-2149
The endosomal LeNHX2 ion transporter exchanges H+ with K+ and, to lesser extent, Na+. Here, we investigated the response to NaCl supply and K+ deprivation in transgenic tomato (Solanum lycopersicum L.) overexpressing LeNHX2 and show that transformed tomato plants grew better in saline conditions than untransformed controls, whereas in the absence of K+ the opposite was found. Analysis of mineral composition showed a higher K+ content in roots, shoots and xylem sap of transgenic plants and no differences in Na+ content between transgenic and untransformed plants grown either in the presence or the absence of 120 mm NaCl. Transgenic plants showed higher Na+/H+ and, above all, K+/H+ transport activity in root intracellular membrane vesicles. Under K+ limiting conditions, transgenic plants enhanced root expression of the high‐affinity K+ uptake system HAK5 compared to untransformed controls. Furthermore, tomato overexpressing LeNHX2 showed twofold higher K+ depletion rates and half cytosolic K+ activity than untransformed controls. Under NaCl stress, transgenic plants showed higher uptake velocity for K+ and lower cytosolic K+ activity than untransformed plants. These results indicate the fundamental role of K+ homeostasis in the better performance of LeNHX2 overexpressing tomato under NaCl stress. 相似文献