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61.
62.
本文介绍了《卡塔赫纳生物安全议定书》的贸易措施 ,以及其与《实施卫生和植物卫生措施协定》、《技术贸易壁垒协定》以及GATT1994等WTO规则的冲突 ,进而指出协调冲突的法律原则和我国的因应之策。  相似文献   
63.
Abstract. Forest herbs differ greatly in their capacity to recolonize secondary forests established on former agricultural land. We investigated whether interspecific differences in recruitment or growth can account for differences in colonization success. Seeds and adults of two species with limited colonization capacities (Anemone nemorosa and Primula elatior) and two species with high colonization capacities (Ranunculus ficaria and Geum urbanum) were introduced in ancient and recent forest sites within the Muizen forest (Belgium). At all sites, half of the plots were also cleared of above‐ground vegetation. Seedling establishment was similar in recent and ancient forest sites. However, both the number and subsequent survival of seedlings of the two hemicryptophytes (G. urbanum and P. elatior) were significantly lower when vegetation cover was present, while seedling number and survival of the two geophytes (A. nemorosa and R. ficaria) were less influenced by vegetation cover. Adult performance of P. elatior and G. urbanum was significantly better in the nutrient enriched recent forest stands and in the absence of vegetation cover. Performance of A. nemorosa and R. ficaria was not affected by any of these factors. We conclude that the extent of seed limitation is probably the main cause for the different colonization capacities of the species investigated.  相似文献   
64.
Ecologists have long sought to understand the relationships among species diversity, community productivity and invasion by non‐native species. Here, four long‐term observational datasets were analyzed using repeated measures statistics to determine how plant species richness and community resource capture (i.e. productivity) influenced invasion. Multiple factors influenced the results, including the metric used to quantify invasion, interannual variation and spatial scale. Native richness was positively correlated with non‐native richness, but was usually negatively correlated with non‐native abundance, and these patterns were stronger at the larger spatial scale. Logistic regressions indicated that the probability of invasion was reduced both within and following years with high productivity, except at the desert grassland site where high productivity was associated with increased invasion. Our analysis suggests that while non‐natives were most likely to establish in species rich communities, their success was diminished by high resource capture by the resident community.  相似文献   
65.
We conducted a decomposition analysis of material flows in a dynamic system, focusing on factors in the generation of waste consumer durables. A methodology for the analysis of consumer durables was developed and applied to three common consumer durables: cathode ray tube TVs, refrigerators, and passenger cars. The methodology decomposed changes in the numbers of waste products into three factors: changes in lifespan distribution, past trends in replacement sales, and past trends in sales for additional purchases. The decomposed equation clearly showed that the number of waste products would not necessarily be reduced by lifespan extension alone. This is because the number of waste products generated is affected not only by current lifespan distribution but also by past trends in sales for replacement and in additional purchases. The results show that changes in past replacement sales influence the current generation of waste, even if current replacement sales are declining. To reduce the generation of waste products on a short‐term basis, lifespan must be extended until the waste‐reducing effect of lifespan extension exceeds the waste‐increasing effect of the other two factors. From a long‐term perspective, controlling current replacement and additional purchases can be used to prevent future waste product generation.  相似文献   
66.
中国东北地区非点源污染研究进展   总被引:9,自引:0,他引:9  
为掌握东北地区非点源污染研究动态和明确研究中存在的问题和不足,对近20年(1991-2008年)东北地区有关非点源污染研究成果进行检索、分类和统计分析,以便更好地进行区域水环境治理和污染防治.东北地区非点源污染研究总体呈增加趋势;研究内容包括水环境污染源调查分析与评价、污染负荷量化、机理探索、模型模拟和污染防治5类;研究对象包括氮、磷、泥沙、农药和重金属;经验方法估算污染负荷较多,机理模型应用成功实例较少;研究性论文中以农业非点源污染较多,城市非点源污染较少;治理措施停留在水土保持措施层面上,缺乏对水土保持措施的优选评价和对最佳管理措施的评价研究.目前,东北地区非点源污染研究处在理论探索阶段,非点源污染是否是主要污染源还存在争议.今后应着力于措施应用、评价和基础数据收集及区域非点源污染物的确定和污染负荷的量化研究;尝试新技术和多领域交叉合作,为区域水环境治理提供科学依据.  相似文献   
67.
福建外来入侵植物初步研究   总被引:8,自引:0,他引:8  
经野外调查和整理分析文献资料,初步认定福建省外来入侵植物并已归化的种类约73种,分属于29科,其中菊科种类最多,有16种。从来源看,来自美洲的有59种,占80.82%。入侵植物中包括6种2003年国家环保总局公布的首批外来入侵物种。文中还对这些外来入侵植物的危害、入侵途径及其防治对策进行讨论。  相似文献   
68.
Purpose: To evaluate the effectiveness of 8-week low-frequency plantar vibration training on patients with sensorimotor diabetic peripheral neuropathy (DPN).

Participants: Twelve patients took part in the investigation.

Results: An increase of the nerve conductive velocity of soral and peroneal nerves of feet, increased postural stability, and disappearance of the pain and tingling were observed.

Conclusion: The obtained results provide evidence for beneficial effects of 8-week plantar vibration training in patients with DPN.  相似文献   

69.
The International Tribunal for the Law of the Sea (ITLOS) has a residual compulsory jurisdiction regarding the prompt release of seized vessels. This procedure is one of the novelties introduced in the UN Convention on the Law of the Sea and is unique in the international judicial universe because of both its procedural characteristics and its functions. This article highlights how prompt release cases do not necessarily stem from a dispute. This has a direct consequence for those whose interests the procedure protects and who can submit an application. The last part of this article discusses the recent trend where the release of vessels and crews has been requested in the context of provisional measures applications.  相似文献   
70.
Non-small cell lung cancer (NSCLC) often metastasizes to the brain, but identifying which patients will develop brain metastases (BM) is difficult. Macroautophagy/autophagy is critical for cancer initiation and progression. We hypothesized that genetic variants of autophagy-related genes may affect brain metastases (BM) in NSCLC patients. We genotyped 16 single nucleotide polymorphisms (SNPs) in 7 autophagy-related (ATG) genes (ATG3, ATG5, ATG7, ATG10, ATG12, ATG16L1, and MAP1LC3/LC3) by using DNA from blood samples of 323 NSCLC patients. Further, we evaluated the potential associations of these genes with subsequent BM development. Lung cancer cell lines stably transfected with ATG16L1: rs2241880 (T300A) were established. Mouse models of brain metastasis were developed using cells transfected with ATG16L1–300T or ATG16L1–300A. ATG10: rs10036653 and ATG16L1: rs2241880 were significantly associated with a decreased risk of BM (respective hazard ratios [HRs]=0.596, 95% confidence interval [CI] 0.398–0.894, P = 0.012; and HR = 0. 655, 95% CI 0.438–0.978, P = 0.039, respectively). ATG12: rs26532 was significantly associated with an increased risk of BM (HR=1.644, 95% CI 1.049–2.576, P = 0.030). Invasion and migration assays indicated that transfection with ATG16L1–300T (vs. 300A) stimulated the migration of A549 cells. An in vivo metastasis assay revealed that transfection with ATG16L1–300T (vs. 300A) significantly increased brain metastasis. Our results indicate that genetic variations in autophagy-related genes can predict BM and that genome analysis would facilitate stratification of patients for BM prevention trials.  相似文献   
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