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The aim of this paper is to assess how policy goals in relation to the promotion of green growth, energy security, pollution control and greenhouse gas (GHG) emissions reductions have been aligned in policies that have been implemented in selected countries during the last decades as a basis for discussing how a multi objective policy paradigm can contribute to future climate change mitigation. The paper includes country case studies from Brazil, Canada, China, the European Union (EU), India, Japan, Mexico, Nigeria, South Africa, South Korea and the United States covering renewable energy options, industry, transportation, the residential sector and cross-sectoral policies. These countries and regions together contribute more than two thirds of global GHG emissions. The paper finds that policies that are nationally driven and that have multiple objectives, including climate-change mitigation, have been widely applied for decades in both developing countries and industrialised countries. Many of these policies have a long history, and adjustments have taken place based on experience and cost effectiveness concerns. Various energy and climate-change policy goals have worked together in these countries, and in practice a mix of policies reflecting specific priorities and contexts have been pursued. In this way, climate-change mitigation has been aligned with other policy objectives and integrated into broader policy packages, though in many cases specific attention has not been given to the achievement of large GHG emission reductions. Based on these experiences with policy implementation, the paper highlights a number of key coordination and design issues that are pertinent to the successful joint implementation of several energy and climate-change policy goals.  相似文献   
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The Australian Alps, which are of high conservation value, are popular summer bushwalking destinations. Experimental trampling trials using a standardized methodology were conducted to determine the resistance and resilience of the two common vegetation types: tall alpine herbfield and subalpine grasslands. Vegetation parameters were measured in lanes subject to control (no trampling), 30, 100, 200, 500 and 700 passes at five sites prior to trampling, immediately post trampling, 2 weeks, 6 weeks and 1 year post trampling. Vegetation height, cover of graminoids and herbs, as well as net species richness all declined with trampling, while litter cover increased. Thresholds for damage varied between the two communities and among the different vegetation parameters. The resistance indices for the two communities (number of passes resulting in 50% reduction in vegetation cover), however, were similar at around 440–450 passes indicating that these two communities are among the most resistant of the 19 alpine–subalpine communities that have been tested around the world, but only of moderate resistance compared to non-alpine communities. The two communities showed limited recovery with damage still evident 1 year post trampling. This indicates that they have only moderate tolerance to damage due to moderate resistance, but low resilience.  相似文献   
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We report an interstitial deletion of chromosome 3q26-q28 in a fetus in which anophthalmia had been detected prenatally. FISH analysis, using BAC clones encompassing the SOX2 locus, showed that SOX2 gene was involved in the chromosomal breakpoint of the deletion. This case confirms that haploinsufficiency for SOX2 plays a crucial role in human eye development and emphasizes the necessity of careful chromosomal analysis, including FISH analysis of the 3q region, in case of prenatal discovery of anophthalmia. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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Utilization of energy substrates during calling activity in tropical frogs   总被引:2,自引:0,他引:2  
Calling activity in frogs is energetically demanding to males because they usually perform at or near their physiological capacities. Metabolic fuel for muscle contractions during bouts of aerobic calling activity comes from carbohydrates and lipids that are stored in the trunk muscles. I monitored nightly calling performance in males of seven tropical frog species from two families, Hylidae and Leptodactylidae, and compared levels of glycogen and lipid in the trunk muscles from males collected before and after a three-hour period of calling activity. Trunk muscles from late-evening males in five species had up to 63% less glycogen than the trunk muscles from early-evening males; relatively little depletion was observed in two other species. Overall, glycogen reserves and rates of depletion were highest in species with very high calling rates. It was not possible to measure changes in the relatively large stores of lipid in the trunk muscles after only 3 h of calling. Nevertheless, intramuscular lipid stores probably provide a greater percentage of the energy needed for sound production than glycogen stores, and are largest in species with high calling rates. Received: 7 January 1997 / Accepted after revision: 20 July 1997  相似文献   
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The level of specialization of the entomopathogenic nematode Steinernema scapterisci with its native Xenorhabdus symbiont was investigated by testing (1) the influence of non-native bacterial strains on nematode fitness within an insect-host (Galleria mellonella) and (2) specificity of the association between the nematode infective juveniles and non-native bacteria. All non-native Xenorhabdus spp. or Photorhabdus spp. strains tested were mutualistically associated with other entomopathogenic nematodes in nature. We showed that most of the Xenorhabdus spp. strains tested led to an insignificant difference of the nematode's fitness compared to the one obtained with the native bacterium. Conversely, Photorhabdus spp. strains almost entirely abolished nematode reproduction. The phylogenetic analysis of bacterial strains tested, showed that there was a negative correlation between S. scapterisci's reproduction rate with a bacterial strain and the genetic distance of this bacterial strain from the native one. We also showed that the native bacterium was the only one which was transmitted by S. scapterisci's infective juveniles. All these results, suggested a specialization between S. scapterisci and its native Xenorhabdus. As the same phenomenon was already demonstrated in the association between S. carpocapsae and X. nematophila, specialization between partners would not be an exception in entomopathogenic nematode-bacteria interactions. Nevertheless, S. scapterisci showed a dramatically higher compatibility with non-native Xenorhabdus spp. strains than did S. carpocapsae, suggesting differences in the co-evolutionary processes between nematodes and bacteria in these two model systems.Table 1 List of the bacterial strains, native nematode species with their geographical origin, accession numbers of bacterial 16S rDNA partial sequences and number of combination experiments for each bacterium tested
Bacterial species and strains Native nematode species Accession no. of the 16S rDNA sequence Geographical origin No. of combination experiments
X. innexi UY61 S. scapterisci AY521243 Uruguay 80
X. poinarii SK72 S. glaseri AY521239 USA 40
X. beddingii Q58 Steinernema sp. D78006 Australia 40
X. bovienii FR10 S. feltiae AY521240 France 40
Xenorhabdus sp. USTX62 S. riobrave AY521244 USA 40
X. nematophila F1 S. carpocapsae AY521241 France 40
P. luminescens TT01 H. bacteriophora AJ007404 Trinidad 40
P. temperata XLNACH H. megidis AJ007405 Russia 40
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