点地梅属的分子系统学、生物地理学和垫状形态的趋同进化     

王玉金  李小娟  郝刚    刘建全 《中国科学院研究生院学报》2004,42(6):481-499

报道了青藏高原地区的点地梅属Androsace L.及羽叶点地梅属Pomatosace Maxim.共14种29个居群的ITS与trnL-F DNA序列各27与25条；并结合已报道相关种类的有关序列，构建了“点地梅群”的分子系统发育树。研究发现“点地梅群”的4个属为一单系类群，含有两个稳定的分支：一支全部由点地梅属的种类组成，另一支分别由羽叶点地梅属、Douglasia Lindley、Vitaliana Sesler和9种点地梅属植物组成；点地梅属裂叶组sect. Samuelia Schlechtd.的3个种与点地梅组sect. Androsace的2个种在3套序列分析中位于不同的系统位置。各分支基部的种都分布在中国东南部及青藏高原东部，分子地理标记的结果支持形态学提出该地区为“点地梅群”植物起源地的假设。从青藏高原东部地区向欧洲及其他北半球地区存在不同时期内多个进化支的多次扩散。粗略的时间估算表明该群植物可能是在第三纪的中新世以来才开始发生的。垫状种类分别在青藏高原和欧洲独立起源，而在青藏高原地区的分化要早于在欧洲的分化，在前一地区可能与青藏高原自中新世开始发生的造山运动、形成高海拔的山地有关，而在后一地区则是与第三纪末至第四纪的冰期气候反复波动有关。垫状植物在青藏高原上的大规模分布则可能较晚，与冰期结束后全新世晚期气候再次变冷有关。一些物种种内的遗传分化也可能部分反映了气候来回波动中它们在高原上的退缩和再扩张过程  相似文献   

The process of designing for learning: understanding university teachers’ design work     

Sue?BennettEmail authorView author&#;s OrcID profile  Shirley?Agostinho  Lori?Lockyer 《Educational technology research and development : ETR & D》2017,65(1):125-145

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利用网上资源制作大学英语课件          下载免费PDF全文

丁刚  郑宗晖 《惠州学院学报》2002,22(6):137-140

课件制作对许多英语教师来说, 仍是一件颇为棘手的事, 要将英语知识在课件中呈现出来, 存在着搜集素材和技术处理上的两大难题. 本文探讨了利用因特网进行大学英语课件制作和教学的构想和方法, 为大学英语课件教学提供了一种新的思路.  相似文献   

阵列波导光栅复用/解复用器输出端模场串扰分析     

李雪梅  陈胜钰 《闽江学院学报》2002,23(6):50-52

阵列波导光栅孔径大小是AWG复用/解复用器件的重要结构参数.大部分耦合进对应输出波导的同时有部分光场耦合进邻近波导,增加了器件的串扰.本文分析了波导光栅孔径有限引起的信号串扰.  相似文献   

应用 MCRT 连续测定运动中心输出量实效性研究     

刘洵  张薇 《天津体育学院学报》1993,8(3):8-11

通过自行设计实验装置对CO_2重复呼吸法施行了改进(MCRT),其目的是能够在不间断的运动中连续地间插测定心输出量(Q)。为了检验它的实效性,我们用MCRT和超声心动图法(ECGT)进行了运动中Q的同步测定,结果二者呈高度相关(r=0.92,P<0.01)。  相似文献   

You Don't Look Like a Librarian: Shattering Stereotypes and Creating Positive New Images in the Internet Age, by Ruth Kneale. Medford, NJ: Information Today, 2009. 198p. $29.50. ISBN 978-1-57387-366-6.     

You Don't Look Like a Librarian: Shattering Stereotypes  Creating Positive New Images in the Internet Age   《The Journal of Academic Librarianship》2009,35(5):58

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Leveraging Enterprise System Technology for Curricular Innovation and Redesign     

Special Issue Guest Editors  
John R. Grandzol David Chou 《Decision Sciences Journal of Innovative Education》2010,8(1):1-3

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The “big red button” is too late: an alternative model for the ethical evaluation of AI systems     

Thomas?ArnoldEmail authorView author&#;s OrcID profile  Matthias?Scheutz 《Ethics and Information Technology》2018,20(1):59-69

As a way to address both ominous and ordinary threats of artificial intelligence (AI), researchers have started proposing ways to stop an AI system before it has a chance to escape outside control and cause harm. A so-called “big red button” would enable human operators to interrupt or divert a system while preventing the system from learning that such an intervention is a threat. Though an emergency button for AI seems to make intuitive sense, that approach ultimately concentrates on the point when a system has already “gone rogue” and seeks to obstruct interference. A better approach would be to make ongoing self-evaluation and testing an integral part of a system’s operation, diagnose how the system is in error and to prevent chaos and risk before they start. In this paper, we describe the demands that recent big red button proposals have not addressed, and we offer a preliminary model of an approach that could better meet them. We argue for an ethical core (EC) that consists of a scenario-generation mechanism and a simulation environment that are used to test a system’s decisions in simulated worlds, rather than the real world. This EC would be kept opaque to the system itself: through careful design of memory and the character of the scenario, the system’s algorithms would be prevented from learning about its operation and its function, and ultimately its presence. By monitoring and checking for deviant behavior, we conclude, a continual testing approach will be far more effective, responsive, and vigilant toward a system’s learning and action in the world than an emergency button which one might not get to push in time.  相似文献   

Ethical values and social care robots for older people: an international qualitative study     

Heather?DraperEmail authorView author&#;s OrcID profile  Tom?Sorell 《Ethics and Information Technology》2017,19(1):49-68

Values such as respect for autonomy, safety, enablement, independence, privacy and social connectedness should be reflected in the design of social robots. The same values should affect the process by which robots are introduced into the homes of older people to support independent living. These values may, however, be in tension. We explored what potential users thought about these values, and how the tensions between them could be resolved. With the help of partners in the ACCOMPANY project, 21 focus groups (123 participants) were convened in France, the Netherlands and the UK. These groups consisted of: (i) older people, (ii) informal carers and (iii) formal carers of older people. The participants were asked to discuss scenarios in which there is a conflict between older people and others over how a robot should be used, these conflicts reflecting tensions between values. Participants favoured compromise, persuasion and negotiation as a means of reaching agreement. Roles and related role-norms for the robot were thought relevant to resolving tensions, as were hypothetical agreements between users and robot-providers before the robot is introduced into the home. Participants’ understanding of each of the values—autonomy, safety, enablement, independence, privacy and social connectedness—is reported. Participants tended to agree that autonomy often has priority over the other values, with the exception in certain cases of safety. The second part of the paper discusses how the values could be incorporated into the design of social robots and operationalised in line with the views expressed by the participants.  相似文献   

The coach–athlete relationship: a motivational model     

Geneviève A Mageau & Robert J Vallerand 《Journal of sports sciences》2013,31(11):883-904

The aim of this paper is to present a motivational model of the coach–athlete relationship that describes how coaches may influence athletes' motivation. In line with cognitive evaluation theory (Deci and Ryan, 1980 Deci EL Ryan RM 1980 The empirical exploration of intrinsic motivational processes In Advances in Experimental Social Psychology, Vol. 13 (edited by L. Berkowitz) pp. 39–80 New York: Academic Press  [Google Scholar], 1985 Deci EL Ryan RM 1985 Intrinsic Motivation and Self-Determination in Human Behavior New York: Plenum Press [Taylor & Francis Online] , [Google Scholar]) and the hierarchical model of intrinsic and extrinsic motivation (Vallerand, 1997 Vallerand RJ 1997 Toward a hierarchical model of intrinsic and extrinsic motivation Advances in Experimental Social Psychology 29 271 360  [Google Scholar], 2000 Vallerand RJ 2000 Deci and Ryan's self-determination theory: a view from the hierarchical model of intrinsic and extrinsic motivation Psychological Inquiry 11 312 318  [Google Scholar]), a motivational sequence is proposed where coaches' personal orientation towards coaching, the context within which they operate, and their perceptions of their athletes' behaviour and motivation influence coaches' behaviours. Also, coaches' behaviours in the form of autonomy-supportive behaviours, provision of structure and involvement have a beneficial impact on athletes' needs for autonomy, competence and relatedness, which, in turn, nurture athletes' intrinsic motivation and self-determined types of extrinsic motivation. Here, we first review coaches' autonomy-supportive behaviours. We then describe the psychological processes through which coaching behaviours have a positive influence on athletes' intrinsic and self-determined extrinsic motivation. Finally, we identify social and personality processes that determine coaching behaviours.  相似文献