60 research outputs found

    2008年奥运会后我国竞技体育竞赛体制的发展方向

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    文章回顾了我国竞技体育竞赛体制的发展历程,分析了现行赛制的优点和弊端,并根据我国的基本国情,阐述了2008年奥运会后,我国竞技体育竞赛体制的发展方向,希望能为我国竞赛体制的完善提供可借鉴的实际意义

    Distributions of dissolved organochlorine pesticides and polychlorinated biphenyls in China coastal waters

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    分析调查了中国部分海域海水中溶解态有机氯农药(OCPS,25种)和多氯联苯(PCbS,6种)的残留分布特征。结果表明,所有采样点都不同程度地受到了OCPS和PCbS的污染,其中福建省福州平潭和莆田湄洲岛的OCPS污染较为严重,浓度分别达到1752.59和796.19 ng/l;而辽宁省的大连老虎滩OCPS污染较轻,浓度为53.63 ng/l。各采样点海域海水中HCHS污染程度一般高于ddTS,HCHS主要以早期残留为主;根据ddT/ddTS的比值推测,在福州平潭、莆田湄洲岛和珠海淇澳岛水体显示有新的ddT输入。在各海域水体中溶解态PCbS的浓度为33.55--474.92 ng/l,均超过了美国环保局规定的海水浓度限值。因此目前我国沿海海域水体中持久性有机污染物有机氯农药和多氯联苯污染仍不能忽视。The concentrations of organochlorine pesticides(OCPs,25) and polychlorinated biphenyls(PCBs,6) in seawater collected from China coast were investigated.The results showed that concentrations of OCPs ranged from 53.63 to 1752.59 ng/L in seawater,and the highest value was in Pingtan(Fuzhou) while the lowest value was in Laohutan(Dalian,Liaoling province).At all of sampling sites,the concentrations of DDTs and HCHs were lower than the limits of national seawater quality standards(class 1),and the concentration of HCHs was higher than that of DDTs.The ratios of DDT/DDTs showed new DDT into Pingtan(Fuzhou),Meizhoudao(Putian) and Qi'aodao(Zhuhai,Guangdong Province),whereas the isomers characteristics for HCHs showed the residues at all sampling sites.The concentrations of dissolved PCBs ranged from 33.55 to 474.92 ng/L in seawater,which were higher than the limit of EPA seawater quality standard.However,the occurrence of OCPs and PCBs in seawater along China coast should be concerned.国家自然科学基金(40476048;20777060);厦门大学新世纪优秀人才计划基

    急性脑卒中患者的记忆障碍与肽类物质的关系

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    本实验对12例缺血性脑血管病(ICVD)患者及12例对照者和12例正常健康对照者进行了临床记忆量表检查,并测定了患者及对照者的CSF、VIP及SS含量。结果:(1) ICVD患者的记忆总分及MQ均显著低于两个对照组;分项测试中联想学习,图像自由回忆成绩亦显著降低。(2) ICVD患者CSF SS含量显著低于对照组。(3) ICVD患者CSF SS含量与MQ呈显著正相关。本结果提示ICVD患者有不同程度的记忆障碍,SS与记忆有关,测定CSF SS对患者记忆状况的判断有参考价值

    铯添加对VO_x/SBA-15催化剂丙烷氧化脱氢性能影响

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    我们考察了碱金属铯的添加对具有单一活性中心(分立的VO4四面体)的VOx/SBA-15催化剂上丙烷氧化脱氢反应性能的影响,发现铯的加入可以显著改善丙烯的选择性.在相同的丙烷转化率时,丙烯选择性提高了约10%.对催化剂的X射线衍射,拉曼光谱,程序升温还原,吡啶吸附IR光谱和程序升温脱附表征结果表明,少量碱金属的加入,并未改变活性中心的结构及其可还原性能,但明显降低了催化剂表面酸量,尤其是B酸量,从而有利于产物丙烯的脱附,抑制了深度氧化产物COx的产生,提高了丙烯的选择性

    Occurrence and Distribution of Organotin Compounds in Thais clavigera from Xiamen Coast

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    采用戊基化格式衍生法,gC-fPd分析了厦门港周边海域9个小岛屿分布的疣荔枝螺(THAIS ClAVIgErA)体内3种丁基锡化合物(buTylTInS)和3种苯基锡化合物(PHEnylTInS)的存在形态与分布特征.结果表明,丁基锡化合物总浓度(ΣbTS)为0.3~70.6ng.g-1,平均值为28.8ng.g-1,以一丁基锡化合物(MbT)为主.苯基锡化合物总浓度(ΣPHTS)为nd~18.8ng.g-1,平均值为7.9ng.g-1,以三苯基锡化合物为主.厦门港周边海域以丁基锡化合物为主要污染物,占到总有机锡化合物(ΣOTS)的74.3%~96.8%.疣荔枝螺体内(ΣbTS)和(ΣPHTS)呈现从厦门港内到港外逐渐降低的趋势.疣荔枝螺体内TbT和TPHT的浓度显示良好的相关关系(r2=0.7109,P<0.01),说明TPHT和TbT来源趋同,即来源于船舶防污涂料,或水产养殖污染源.与我国东南沿海港口相比,厦门海域疣荔枝螺体内丁基锡化合物的污染处于一个较低水平但比2002年有所加重.Occurrence and distribution of 6 organotin compounds including butyltin and phenyltin species were detected in Thais clavigera which were collected from 9 coastal areas sites around Xiamen Coast,by pentylized derivatization,GC-FPD.Results indicated that all Thais clavigera samples were contaminated with organotin compounds.The concentrations in Thais clavigera soft bodies varied from 0.3 to 70.6 ng.g -1 with a mean value of 28.8 ng.g -1 for butyltin compounds,and from nd to 18.8 ng.g -1 with a mean value of 7.9 ng.g -1 for phenyltin compounds,respectively.MBT and TPhT were high levels in butyltin compounds and phentyltin compounds,respectively.In addition,butyltin compounds were the dominant contaminates in all samples with high percentage from 74.3% to 96.8%.There was a significant correlation between TBT and TPhT (R2 = 0.710 9,p < 0.01).This result showed that both TBT and TPhT came from antifouling paints for ships or for mariculture nets.Compared with those data reported from the other regions around southeast coast of China,present study reveals that contaminated level of organotin compounds in Thais clavigera are relatively lower in Xiamen Coast.But it is higher than those in 2002.国家自然科学基金项目(40476048;20777060

    Imposex of Thais clavigera and Cantharus cecillei in the coastal waters of Xiamen

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    海产腹足类性畸变以其对有机锡的敏感性、特异性和不可逆性而成为海洋有机锡污染的理想指示种。调查研究了厦门海域岩相海岸带疣荔枝螺(THAIS ClAVIgErA)和甲虫螺(CAnTHAruS CECIllEI)的性畸变情况,通过生物学指标IOI(性畸变率)、rPSI(相对阴茎发展指数)、VdSI(输精管发展指数)及SrI(性比指数)综合评价其性畸变发展程度,间接指示厦门周边海域的有机锡污染程度。研究结果发现,在采集疣荔枝螺的17个站点中有5个站点种群性畸变率为100%,其中宝珠屿种群性畸变程度最为严重,VdSI达4,采集甲虫螺的4个站点的种群性畸变率均为100%。性畸变程度较严重的种群普遍集中于厦门西港,并且表现出由港内到港外逐渐减轻的趋势,而白城、会展中心和大嶝岛等位于开阔的厦门东海域的种群性畸变程度最轻,与往年厦门西海域有机锡污染监测数据相比一致,体现出性畸变程度与有机锡污染程度及海港码头远近之间的相互关系。The degree of imposex,i.e.the imposition of male characteristics onto females,in neogastropods can be used as a sensitive and accurate biomarker to evaluate organotin contamination in coastal marine environment.Now,the imposex status in females of Thais clavigera and Cantharus cecillei in 17 sites was investigated to evaluate the organotin contamination along Xiamen Bay during 2006 and 2007.The four indices including incidence of imposex(IOI),relative penis size index(RPSI),vas deferens sequences index(VDSI) and sex ratio index(SRI) were used comprehensively to assess the imposex status in order to ascertain the extent of organotin bioavailability in Xiamen Bay.Based on this research,T.clavigera in 5 sites and C.cecillei in all survey sites exhibited the IOI of 100%.At Bao ZhuYu Islet,the imposex level was the most serious with maximum VDSI value of 4.In general,the imposex level decreased from the inner to the outer of Xiamen Western Harbour,and the populations in the open Xiamen Eastern Waters including Bai Cheng,Convention and Exhibiton Center and Dadeng Island showed a lower imposex level.These results were accordant with the concentrations of organotins in 2005.The imposex degree also increased with increasing organotin contamination and decreasing distance from shipping facilities.国家自然科学基金资助项目(40476048);厦门大学近海海洋环境科学国家重点实验室开放基金资助项目;厦门大学新世纪优秀人才计划基金资助项

    类泛素蛋白及其中文命名

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    泛素家族包括泛素及类泛素蛋白,约20种成员蛋白.近年来,泛素家族领域取得了迅猛发展,并已与生物学及医学研究的各个领域相互交叉.泛素家族介导的蛋白质降解和细胞自噬机制的发现分别于2004和2016年获得诺贝尔奖.但是,类泛素蛋白并没有统一规范的中文译名. 2018年4月9日在苏州召开的《泛素家族介导的蛋白质降解和细胞自噬》专著的编委会上,部分作者讨论了类泛素蛋白的中文命名问题,并在随后的\"泛素家族、自噬与疾病\"(Ubiquitinfamily,autophagy anddiseases)苏州会议上提出了类泛素蛋白中文翻译草案,此草案在参加该会议的国内学者及海外华人学者间取得了高度共识.冷泉港亚洲\"泛素家族、自噬与疾病\"苏州会议是由美国冷泉港实验室主办、两年一度、面向全球的英文会议.该会议在海内外华人学者中具有广泛影响,因此,参会华人学者的意见具有一定的代表性.本文介绍了10个类别的类泛素蛋白的中文命名,系统总结了它们的结构特点,并比较了参与各种类泛素化修饰的酶和它们的生物学功能.文章由45名从事该领域研究的专家合作撰写,其中包括中国工程院院士1名,相关学者4名,长江学者3名,国家杰出青年科学基金获得者18名和美国知名高校华人教授4名.他们绝大多数是参加编写即将由科学出版社出版的专著《泛素家族介导的蛋白质降解和细胞自噬》的专家

    Urbanization spatial expansion and regional landscape ecological risk of Yantai City

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    采用遥感、GIS及数理统计方法,引入城市扩展强度指数研究了烟台市区1974—2009年城镇空间扩展时空变化特征,并利用景观指数和生态风险指数,研究了1990—2009年在城镇扩展下的烟台市区城镇景观格局动态变化和区域生态风险空间特征。结果表明:1974—2009年,烟台市区城镇用地面积增幅189.77 km~2,其中2004—2009年城镇用地扩展强度指数是1974—1990年的3.92倍。城镇和耕地分别是研究区土地利用面积变化最显著的两大类型,土地利用格局景观指数变化反映出该期间人类活动干扰强度逐渐加剧。研究区景观生态风险呈圈层状分布,靠近海岸线的区域生态风险较高,远离海岸线的内陆生态风险则较低。2009年高生态风险区和较高生态风险区比例是1990年的2.23倍,城镇扩展强度与区域生态风险之间呈现良好的线性关系
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