九寨沟、黄龙风景区的降水特征及其变化

利用九寨沟、黄龙地区附近代表站的降水资料及NCEP/NCAR 1959年～2002年共44年月平均再分析资料采用小波分析、合成分析等方法对九寨沟、黄龙地区降水以及水汽输送特征进行了研究。结果表明，九寨沟、黄龙地区的年降水总量为693.7 mm,降水主要集中在5月～9月，干湿季明显，7月份降水最多。44年来本区年降水量呈减少趋势。降水的减少主要发生在夏季，尤其是7月。九寨沟、黄龙地区的水汽输送有着明显的季节变化，这种差异和季风环流演变有密切的关系。冬、春季本区的水汽主要来源于中纬度偏西风水汽输送，夏、秋季节主要来源于孟加拉湾和南海、西太平洋地区。夏季风的异常变化引起的南来水汽向北输送的减弱，是造成九寨沟、黄龙地区降水减少的重要原因之一。九寨沟、黄龙地区多雨年和少雨年来自西太平洋、东海的水汽输送特征有显著差异，多（少）雨年来自西太平洋、东海地区的水汽输送显著偏多（少）。     

“日光城”拉萨日照时数的变化特征

利用拉萨1970年～2004年的日照时数、水汽压、降水、云量等资料,采用气候统计方法讨论了35年来拉萨日照时数气候变化特征及变化原因,主要得出以下结论:拉萨年日照时数达2 980h;一年中10月份的日照时数最长,长达281h,8月份日照时数最短,为219h。4个季节中,秋季日照最丰富,长达777h,其次是春季、冬季,分别为769h、736h,夏季最少为698h。1970年～2004年以来拉萨的年日照时数呈减少趋势,平均每10年减少近58h,20世纪90年代末期以来日照时数更是显著减少;4个季节中夏季日照时数的减少幅度最大,减幅为27h/10年。大气水汽压、降水是影响拉萨日照时数变化的主要因子,尤其是20世纪90年代以来,它们的显著增加对该时期日照时数的减少有着重要贡献。     

金沙江流域及邻近地区空中水资源的气候特征分析

本文研究了长江上游金沙江流域及邻近地区空中水资源的气候特征,主要结论如下:①金沙江流域大气可降水量具有明显的季节变化特征,冬季最低,夏季最高。流域主要位于高原东侧大气可降水量最大经向梯度带上,受到了高原大地形的显著影响;②冬、春季节金沙江流域水汽主要来源于中纬度偏西风水汽输送,高原南侧经过孟加拉湾北部的南支偏西风水汽的贡献尤其重要;夏季该流域上空水汽主要来源于孟加拉湾和南海、西太平洋地区;秋季则主要来源于南海、西太平洋地区;③20世纪60年代至今,金沙江流域的主要水汽源地、水汽输送通道上空大气可降水量总体呈增加趋势,尤其是20世纪90年代以来,上述区域上空增湿更是明显;1958年-2002年金沙江流域大部分地区夏季水汽输送总体呈增强趋势,主要由纬向输送增强所致;④近年来金沙江流域整体大气降水、径流量地增加以及极端天气气候事件的频繁发生都与空中水资源的变化密切相关。     

柴达木盆地气候的变化对水资源的影响

本文利用累积距平等方法对柴达木盆地近46年(1961～2006年)来的气温、降水和径流量资料进行了分析,探讨了柴达木盆地气候的变化对水资源的影响。结果显示:柴达木盆地近46年来气温和降水呈上升、径流量呈减小趋势;气温变幅大,降水、径流量变幅小;气温升高、降水少、蒸发量加大是造成该地区水资源减少的主要原因之一。     

浙江金华秋季异常降水的水汽输送特征

为了填补金华乃至浙江秋季降水研究空白,本文利用NCEP再分析资料和1971—2020年秋季实测降水资料,结合水汽通量及散度场,并基于拉格朗日法的轨迹模式HYSPLIT-4,对金华市50年来秋季异常降水年不同高度的水汽输送特征进行研究。结果表明：(1)金华秋季降水的水汽通道主要有4条,欧亚非大陆的陆上通道、西太平洋通道、孟加拉湾-南海通道以及局地水汽通道。(2)金华秋季降水的水汽输送在不同高度存在差异,典型旱年中低层以局地水汽输送为主,高层以孟加拉湾-南海和西太平洋的水汽输送为主;影响典型涝年的水汽输送在中低层上源自西太平洋,高层源自孟加拉湾-南海。(3)西太平洋和孟加拉湾-南海是导致金华秋季降水异常的关键水汽源区,其中典型涝年西太平洋的水汽贡献率较旱年增强12.36%,孟加拉湾-南海增强15.79%,并且异常水汽主要以西南气流的形式输入金华影响降水。     

浙江省秋季降水特征及其对太平洋海温的响应

利用1960-2008年浙江省秋季降水资料计算了秋季区域降水指数,基于NCEP/NCAR全球多个再分析资料、SST资料,采用相关分析、趋势分析、Mann-Kendall突变检验等统计方法分析了浙江省秋季降水的长期气候特征、水汽输送通道、秋季降水对SST的响应以及和500 hPa高度场的遥相关。结果表明:近49年来浙江秋季降水呈现显著的下降趋势,1990年前后发生突变;太平洋、南海以及孟加拉湾地区是浙江秋季降水的水汽来源;影响浙江省秋季降水的SST关键区域是中太平洋海盆西南部海区,关键期是当年的6～8月,该区域SST突变前后,秋季500 hPa高度场变化显著;青藏高压、东亚大槽、西太平洋副高和印缅槽是影响浙江省秋季降水的主要天气系统。     

杭州空中水资源和降水转化率分析

采用NCEP/NCAR再分析资料和月降水资料,对杭州地区近66年的空中水资源和降水转化率特征进行了分析研究。结果表明:杭州年平均水汽含量为28～30 mm,夏季最高,春、秋季次之,冬季最低。空间分布上,南高北低。时间演变上,年平均和春、秋季水汽含量均呈下降趋势,春季的下降趋势更显著,夏季呈弱上升之势,冬季在20世纪无明显趋势,21世纪后显著减小,其中除冬季外,其余均通过了0. 05的显著性检验。杭州平均季节降水转化率最大为冬、春季,其次是夏季,最小为秋季,降水转化率普遍偏低,空中水资源开发潜力巨大。水汽含量与降水的相关性较好,其可作为降水预报的指标之一。除水汽条件外,散度、尤其是涡度等动力场的配置是决定降水转化率高低的重要因素。     

呼和浩特市一次暴雨过程中北部偏大的成因分析

利用台站加密资料和Micaps资料等,从天气形势、物理量场、云图雷达应用等方面做了分析,得出中北部降水偏大、南部偏小的原因为:2018年7月23日凌晨中北部有MCS生成,对流性质显著,有短时强降水发生;台风外围水汽供应充足,偏东风携带水汽主要影响中北部地区;水汽辐合位置偏北,降水集中在中北部,导致本次过程中北部偏大,南部偏小。     

1961年～2004年东北地区四季降水的时空演变特征

利用Anusplin插值软件对东北地区146站1961年～2004年四季降水量进行空间化处理,各季区域平均MRE分别为春季14.3%、夏季14.1%;秋季18.1%;冬季25.1%。对栅格数据采用空间分析和时间序列分析相结合的方法进行四季降水时空演变特征分析,结果表明：从时间上看,春季,整个时段呈弱增多趋势,但不显著,1980年代前增加,之后减少;夏季呈减少趋势,1985以后呈显著减少趋势;秋季整个时段呈弱的减少趋势,1990年代开始显著减少,2000年以后略有增加;冬季年代际变化特征明显,呈波动增多趋势,近10年增幅较大。从空间分布上看,春季,黑龙江北部和东部部分地区、吉林东部降水显著增多,增幅为(3～9)mm/10年,辽宁中部部分地区降水显著减少,减幅为(3～7)mm/10年。夏季,东北大部地区降水以减少为主,黑龙江中部和辽东半岛地区显著减少,减幅为(20～40)mm/10年。秋季,东北大部地区降水减少,黑龙江东部局部、吉林中部和南部部分地区显著减少,减幅为(6～10)mm/10年。冬季,黑龙江大部、吉林大部降水显著增多,增幅为(1～3)mm/10年,辽宁南部和西部部分地区显著减少,减幅为(1～2)mm/10年。     

金沙江流域汛期径流量变化的气候特征分析

利用金沙江流域的直门达、石鼓、小得石以及屏山4个站的径流量,以及NCEP／NCAR再分析资料和我国地面观测站逐日降水资料,研究了金沙江流域汛期（7月-9月）径流量变化的气候特征,结果表明：汛期金沙江流域径流量的年际变化趋势并不显著;直门达站径流量以2～4a时间尺度为主要振荡周期;而石鼓、屏山以及小得石站径流量在1970年前后存在显著突变,这种突变主要体现为变率突变,1970年以前振荡周期以2～4a时间尺度为主,1970年以后振荡周期则转变为以8～16a时间尺度为主;当伊朗高原至青藏高原中西部地区上空的西风水汽输送加强（减弱）时,三江源地区的降水增加（减少）,有利于金沙江流域源头径流量增加（减少）;当沿青藏高原南侧边缘西风水汽输送以及中国东部至日本附近地区气旋性水汽输送环流西侧的东北水汽输送加强（减弱）时,金沙江上游及雅砻江中下游沿岸降水偏多（偏少）,导致金沙江中下游径流量增多（减少）。     

Students' Reactions to the Introduction of Videoconferencing for Classroom Instruction

This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors.     

Cooler temperatures inductive to locust outbreaks

Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007.     

Exploring Multiplexity: Social Network Structures in a Computer-Supported Distance Learning Class

A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction.     

The Role of Intermediating Institutions in the Diffusion of Electronic Data Interchange (EDI): How Industry Associations Intervened in Denmark, Finland, and Hong Kong

Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies.     

Low doses of a red wine ingredient figh diabetes in mice

Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said.     

How Electronic Publishers are Protecting Against Piracy: Doubts About Technical Systems of Protection

The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means.     

Rough Justice: A Statistical Assessment of ICANN's Uniform Dispute Resolution Policy

Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP.     

Prevalence of soft neurological signs in Chinese people

Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.     

Molecular motor assembly of a biomimetic system

Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction.     

Monoculture Rubber Plantations Have Negative Ef ects on Controlling Splash Erosion

<正>In Xishuangbanna,one of China’s most biodiverse regions,landscape has changed dramatically during the past three decades due to the conversion of tropical rainforest to rubber plantations.In steep areas,terraces are often constructed before planting rubber trees,which causes two important changes in the soil:the destabilization of soil in the bench terraces and the increased vulnerability of unvegetated riser faces to erosion.Few studies have documented the nature and intensity of erosion on bench terraces.Prof.LIU Wenjie and his colleagues from the Xishuangbanna Tropical Botanical Garden(XTBG)conducted a study in Menglun County(21°5′39″N,101°15′55″E),Xishuangbanna to evaluate the influence