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Triads of male NMRI mice were housed together and dominance hierarchies allowed to form. At age 19 weeks the mice were ranked on the basis of wins in spontaneous aggressive encounters, and whole-body volatiles were sampled by the dynamic solvent effect and quantitatively analysed by capillary gas chromatography. At age 26 weeks the mice were again ranked on the basis of wins in aggressive encounters, number of aggressive encounters initiated, and scent marking patterns, and whole-body volatiles were sampled and analysed. Chromatographic odour profile ranks agreed perfectly with aggressive initiator ranks and poorly with encounter winner ranks. Eight components of the whole-body odour were identified by gas chromatography-mass spectrometry; two of these are known semiochemicals. The results demonstrate that murine semiochemicals are accessible to quantitative analysis at the level of the individual.  相似文献   
23.
就21世纪消化病的研究与发展的方向和展望,从宏观调控与哲学思想方面提出了如下几个措施;预防为主,人文社会为本;加强基础研究,充分利用科技成果;突出重点,循序渐进;促进中西医结合,充分利用和研究中医药的临床疗效;重视人才培养,提高梯队素质。  相似文献   
24.
小学一~三年级儿童加减法策略选择的发展特点研究   总被引:6,自引:3,他引:3  
随机选取90名小学一~三年级的儿童为被试,采用实验法和访谈法对儿童解决加减法算术题的策略发展特点进行了探讨。结果发现:1儿童能运用多种策略解决加减法算术题,在解决两个数的算术题时用到了13种策略,在解决三个数的算术题时用到了8种策略。2儿童在解决同一道题时大多能同时运用两种或两种以上的策略。3随着年龄的增长,儿童使用策略的总目呈简约化发展的趋势。4在解决两个数的算术题时,不同年级的儿童在使用出声策略、拆十策略、手势策略、逆算策略、数数策略的次数上差异显著,随着年级的增长其使用频率逐渐降低。5儿童在解决三个数的算术题时,各年级儿童使用出声策略、手势策略、对位策略差异显著,随着年级的增长其使用频率逐渐增高。  相似文献   
25.
小学2~4年级儿童数学应用题表征策略差异的研究   总被引:9,自引:0,他引:9       下载免费PDF全文
本研究运用实验法和临床访谈法对某普通小学的123名2~4年级学生进行了数学应用题测验,以考察数学学优生和学差生在解决比较应用题时表征策略的差异。结果表明:(1)从2~4年级儿童解答一致和不一致应用题上看,学优生较多地使用问题模型策略对问题进行表征,学差生较多地使用直接转换策略对问题进行表征;(2)除学差女生的解题正确率低于学差男生的正确率,学差女生自我报告中直接转换策略的使用多于学差男生外,在其它方面,性别差异并不显著;(3)随着年级的升高,学优生在使用问题模型策略上越来越成熟,学差生并没有学会使用更加有效的问题模型表征策略,仍然停留在直接转换策略上,但他们在关于策略使用的认识上有所提高。  相似文献   
26.
This paper addresses the question of how symbols should be understood in analytical psychology and psychoanalysis. The point of view examined focuses on the recent turn to more cognitive and developmental models in both disciplines and briefly reviews and critiques the evolutionary and cognitive arguments. The paper then presents an argument based on dynamic systems theory in which no pre-existing template or structure for either mind or behaviour is assumed. Within the dynamic systems model the Self is viewed as an emergent phenomenon deriving from the dynamic patterns existing in a complex system that includes the physiological characteristics of the infant, the intentional attributions of the caregiver and the cultural or symbolic resources that constitute the environment. The symbol can then be seen as a discrete, and in important ways an autonomous, element in the dynamic system. Conclusions are drawn for further research into the nature of the symbol with implications for both theory and practice in analytical psychology and psychoanalysis.  相似文献   
27.
This study examined how young children change their strategies for size comparison. Twenty-two 5 and 6-year-old children were asked to compare the sizes of geometric figures and their strategies were observed once a week over three weeks. Half of the children were also asked to evaluate presented strategies for comparing geometric figures. It was found that over three weeks not only children who evaluated the strategies but also children who did not increased correct responses, the strategy of placing one figure on another, and the strategy of adjusting two figures by two dimensions. Although more children became aware of the effectiveness of those strategies, there was no relationship between the evaluation and use of strategies.  相似文献   
28.
This paper considers a new class of agent dynamic logics which provide a formal means of specifying and reasoning about the agents activities and informational, motivational and practical aspects of the behaviour of the agents. We present a Hilbert-style deductive system for a basic agent dynamic logic and consider a number of extensions of this logic with axiom schemata formalising interactions between knowledge and commitment (expressing an agent s awareness of her commitments), and interactions between knowledge and actions (expressing no learning and persistence of knowledge after actions). The deductive systems are proved sound and complete with respect to a Kripke-style semantics. Each of the considered logics is shown to have the small model property and therefore decidable.Presented by Ewa Orlowska  相似文献   
29.
Describes the application of a new analytical approach (derived from synergetics, a complex dynamic systems theory) to home observational data of mother–child interactions in average dyads and dyads with children referred for disruptive behavior problems at home and school (n = 11 in each group). Results show that (1) the two groups differed in their daily interactions in predictable ways, and (2) the most frequent patterns of interactions observed in the two groups brought them back repeatedly to behave in similar ways toward each other. The findings are in keeping with a body of literature on mother–child interactions. However, they add to it by providing multivariate, graphical representations of these interactions and by offering a conceptual framework within which to move from an observational to an inferential level of analysis. At that level, the transactional processes that are characteristic of functional and dysfunctional relationships may become apparent.  相似文献   
30.
This article highlights some of the conceptual and methodological problems associated with quality of life (QoL) measurement in individuals with neurological illness. It is suggested that these problems have contributed to the underdeveloped status of QoL research in neurological settings. Many of the existing QoL measures that have been used, or show potential for use with individuals with neurological illness, are reviewed in terms of their theoretical basis, content, and practicality. A large proportion of these measures fail to meet adequate psychometric standards and/or have rarely been psychometrically tested. The confusion that surrounds adequate psychometric standards is discussed, and the dynamic nature of QoL is highlighted as a factor that requires further attention. Research addressing the discrepancies between proxy and patient ratings of patient QoL is also warranted. More focused research in these areas may contribute to a clearer understanding of how to assess QoL in individuals with neurological illness.  相似文献   
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