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41.
Many properties being acquired as part of the Comprehensive Everglades Restoration Plan (CERP) are heavily contaminated with copper. Estimated copper bioaccumulation in the Florida apple snail (Pomacea paludosa) has led to the prediction of risk to the Everglade snail kite (Rostrhamus sociabilis plumbeus) at some CERP projects. Field study results presented in this paper examine the relationship between copper levels in sediments, snails, and other biota. Copper concentrations in all biota (snails, aquatic vascular plants, and periphyton) were strongly correlated with those in sediments. No correlation with water copper concentrations was evident. Mean copper concentrations in snails ranged from 23.9 mg/kg at the reference site to 732 mg/kg at a high copper site. Calculated biota-sediment accumulation factors (BSAFs) ranged from 36.7 to 7.0 over the range of copper levels in sediments. BSAFs were highest at low copper levels in sediments and declined sharply as copper levels in sediment increased. Risk for the snail kite is discussed in light of the results of this study.  相似文献   
42.
《Vaccine》2020,38(33):5109-5113
A National Immunization Technical Advisory Group (NITAG) is a multi-disciplinary body of national experts that provides evidence-based recommendations to policy-makers, assisting them in making sound immunization policy and programme decisions. The World Health Organization (WHO) Regional Office for Europe is working to strengthen the capacity of newly-established NITAGs and has targeted efforts on low- and middle-income countries. The Regional Office, in collaboration with WHO Headquarters and USA Centers for Disease Control and Prevention (CDC), developed a new training strategy and held training workshops to improve NITAGs’ functioning and ability to make evidence-based recommendations. Feedback from countries that participated in trainings indicated that the updated training materials and interactive approach with follow-up technical support enabled them to align their NITAG charters and processes with WHO recommendations. To ensure continued progress, global and regional partners such as WHO and CDC should continue providing technical support to recently established NITAGs.  相似文献   
43.
目的 基于AERMOD模型机理,研究其在核设施辐射环境影响评价中的应用。方法 根据给定的释放源项和厂址气象数据,模拟获取核设施常规运行时气态放射性核素浓度分布,并进一步定性分析气态流出物浓度峰值落地点和时间分布,研究AERMOD模型在核设施辐射环境影响评价中的适用性和应用前景。结果 通过AERMOD模型适用性和应用前景分析,得出该模型总体满足核设施气态流出物浓度分布计算需求,可应用于核设施气态流出物扩散趋势和敏感点分析,并可为核设施常规运行的监测计划提供数据支撑。结论 本研究可为今后深入开展AERMOD模型在核设施辐射环境影响评价中的应用提供参考。  相似文献   
44.
【目的】 探析我国近些年创办的优秀英文科技期刊办刊经验,为我国创办世界一流英文新刊提供借鉴。【方法】 采用文献调研和网站调研等方法,全面扫描2010年之后创办的入选“中国科技期刊卓越行动计划”领军期刊、重点期刊和梯队期刊的37种英文科技期刊的运营现状,分析英文科技期刊发展的重要影响因素。【结果】 入选期刊在与国际出版机构合作、采用国际化编委、注重稿源国际化、重视开放获取和网络首发等新型出版模式、重视数据库收录等方面具有很大的共性,对于新创办英文期刊具有很强的借鉴意义。【结论】 国际化发展道路是我国英文科技期刊的必然选择,新创英文科技期刊还应该在编辑队伍国际化、期刊宣传推广等方面加大建设力度。  相似文献   
45.
“中国科技期刊卓越行动计划”资助期刊特征分析   总被引:6,自引:0,他引:6  
杨睿  王宝济 《浙江预防医学》2020,31(9):1101-161
【目的】 对“中国科技期刊卓越行动计划”资助期刊的特征进行分析,可以了解这些具有较高国际影响力的国内科技期刊的特点,为其他有潜力的科技期刊发展提供参考。【方法】 利用文献调研、网站调研、统计分析等方法对入选科技期刊的主办及主管单位、学科类别、国内外学术影响力等方面进行系统剖析,同时通过SCI收录情况与JCR分区指标对顶层的领军期刊和重点期刊进行重点分析。【结果】 领军期刊和重点期刊项目重点支持英文期刊;以域选刊,重点关注优先建设领域;所有期刊均被SCI收录,主要引证指标表现优秀。梯队期刊兼顾中、英文期刊;资助数量最多,覆盖学科领域较广;整体国际学术影响力不高,但其中的中文期刊具有较高的国内影响力。高起点新刊项目主要支持英文期刊,关注优先建设领域。【结论】 “中国科技期刊卓越行动计划”资助期刊在国际影响力、主要引证指标、出版体系等方面呈现出尖兵引领、梯次跟进的态势,同层次期刊可以逐步探索良性的竞争与合作模式,冲击更优、更强的国际一流期刊;未受到资助的期刊可参照相应的指标不断追跑,从而促进我国科技期刊体系的持续健康发展。  相似文献   
46.
《Vaccine》2019,37(35):4928-4936
BackgroundThe pace of global progress must increase if the Global Vaccine Action Plan (GVAP) goals are to be achieved by 2020. We administered a two-phase survey to key immunization stakeholders to assess the utility and application of GVAP, including how it has impacted country immunization programs, and to find ways to strengthen the next 10-year plan.MethodsFor the Phase I survey, an online questionnaire was sent to global immunization stakeholders in summer 2017. The Phase II survey was sent to regional and national immunization stakeholders in summer 2018, including WHO Regional Advisors on Immunization, Expanded Programme on Immunization managers, and WHO and UNICEF country representatives from 20 countries. Countries were selected based on improvements (10) versus decreases (10) in DTP3 coverage from 2010 to 2016.ResultsGlobal immunization stakeholders (n = 38) cite global progress in improving vaccine delivery (88%) and engaging civil society organizations as advocates for vaccines (83%). Among regional and national immunization stakeholders (n = 58), 70% indicated reaching mobile and underserved populations with vaccination activities as a major challenge. The top ranked activities for helping country programs achieve progress toward GVAP goals include improved monitoring of vaccination coverage and upgrading disease surveillance systems. Most respondents (96%) indicated GVAP as useful for determining immunization priorities and 95% were supportive of a post-2020 GVAP strategy.ConclusionsImmunization stakeholders see GVAP as a useful tool, and there is cause for excitement as the global immunization community looks toward the next decade of vaccines. The next 10-year plan should attempt to increase political will, align immunization activities with other health system agendas, and address important issues like reaching mobile/migrant populations and improving data reporting systems.  相似文献   
47.
结合北京大学第三医院医学生殖中心净化工程设计与施工配合的工作经历,重点分析了医学辅助生殖中心的平面设计布置、流程及细节的设计。  相似文献   
48.

Ethnopharmacological relevance

Rheum australe D. Don (Polygonaceae) has been commonly used in traditional medicine for a wide range of ailments related to the circulatory, digestive, endocrine, respiratory and skeletal systems as well as to infectious diseases.

Aim of the review

To provide the up-to-date information that is available on the botany, traditional uses, phytochemistry, pharmacology and toxicology of Rheum australe. Additionally, to highlight the possible uses of this species to treat different diseases and to provide a basis for future research.

Materials and methods

The present review covers the literature available from 1980 to 2011. The information was collected from scientific journals, books, theses and reports via a library and electronic search (Google Scholar, Web of Science and ScienceDirect).

Results

Ethnomedical uses of Rheum australe have been recorded from China, India, Nepal and Pakistan for 57 different types of ailments. The phytochemical studies have shown the presence of many secondary metabolites belonging to anthraquinones, stilbenes, anthrones, oxantrone ethers and esters, chromones, flavonoids, carbohydrate, lignans, phenols and sterols. Crude extracts and isolated compounds from Rheum australe show a wide spectrum of pharmacological activities, such as antidiabetic, anti-inflammatory, antifungal, antimicrobial, antioxidant, anticancer, hepatoprotective and immune-enhancing activities, as well as a usefulness for improving renal function.

Conclusion

Rheum australe has been widely used source of medicine for years without any adverse effects. Many studies have provided evidence for various traditional uses. However, there is a need for additional studies of the isolated compounds to validate the traditional uses in human models. The present review on the botany, traditional uses, phytochemistry and toxicity has provided preliminary information for further studies and commercial exploitations of the plant.  相似文献   
49.
在介绍多种生活垃圾收集方式、方法的基础上,提出采用综合分析的方法进行收集系统规划,进而提出收集系统设施设置和设备配置的要求,为城市生活垃圾收集系统规划编制提供思路。  相似文献   
50.
探讨放射科PACS工作站等软、硬件的配置,提高医学图像的显示质量。单机双显配置结合适宜的软、硬件配置可以提高PACS中医学影像的显示质量。  相似文献   
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