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91.
Nevin's scholarly and timely discussion attempts to maintain the precarious union of the experimentally derived theory of behavioral momentum with applications of the behavioral momentum construct to human subjects in applied settings. Nevin's discussion adds much-needed clarification to a process that at times has proven to be awkward for applied researchers. In this commentary, we will address three general questions: (a) Can the applications of behavioral momentum be derived from the theory as conceptualized by Nevin? (b) Could those applications have been developed had the theory not been formulated? (c) Does behavioral momentum theory add significantly to the compliance literature? 相似文献
92.
The skill of rhythmically juggling a ball on a racket was investigated from the viewpoint of nonlinear dynamics. The difference equations that model the dynamical system were analyzed by means of local and nonlocal stability analyses. These analyses showed that the task dynamics offer an economical juggling pattern that is stable even for open-loop actuator motion. For this pattern, two types of predictions were extracted: (a) Stable periodic bouncing is sufficiently characterized by a negative acceleration of the racket at the moment of impact with the ball, and (b) a nonlinear scaling relation maps different juggling trajectories onto one topologically equivalent dynamical system. The relevance of these results for the human control of action was evaluated in an experiment in which subjects (N = 6) performed a comparable task of juggling a ball on a paddle. Task manipulations involved different juggling heights and gravity conditions of the ball. The following predictions were confirmed: (a) For stable rhythmic performance, the paddle's acceleration at impact is negative and fluctuations of the impact acceleration follow predictions from global stability analysis; and (b) for each subject, the realizations of juggling for the different experimental conditions are related by the scaling relation. These results permit one to conclude that humans reliably exploit the stable solutions inherent to the dynamics of the given task and do not overrule these dynamics by other control mechanisms. The dynamical scaling serves as an efficient principle for generating different movement realizations from only a few parameter changes and is discussed as a dynamical formalization of the principle of motor equivalence. 相似文献
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Steiner D 《Science and engineering ethics》1996,2(4):457-468
Individual and institutional conflict of interests in biomedical research have becomes matters of increasing concern in recent
years. In the United States, the growth in relationships — sponsored research agreements, consultancies, memberships on boards,
licensing agreements, and equity ownership — between for-profit corporations and research universities and their scientists
has made the problem of conflicts, particularly financial conflicts, more acute. Conflicts can interfere with or compromise
important principles and obligations of researchers and their institutions, e.g., adherence to accepted research norms, duty
of care to patients, and open exchange of information. Disclosure is a key component of a successful conflict policy. Commitments
which conflict with a faculty member's primary obligations to teaching, research, administrative responsibilities, or patient
care also need attention. Institutional conflict of interests present different problems, some of which are discussed in an
analysis of an actual problem posed by two proposed clinical trials.
This paper is adapted from a lecture presented to a Symposium on Scientific Integrity, Warsaw, Poland, 23 November 1995.
Daniel Steiner was Vice-President and General Counsel of Harvard University (1972–92) and in that capacity became familiar
with conflict of interest issues. He is currently Counsel to the Boston law firm. Ropes and Gray, and is Adjunct Lecturer
in Public Policy at the John F. Kennedy School of Government. Harvard University. 相似文献
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我们这篇文章专门用来论讨在直接再现和延缓再现中,记忆和思维相互关系这个当前必须解决的问题А·А·斯米尔诺夫早就证实过,积极的思维活动是提高不随意识记效率的基础。积极思维活动的内容越复杂,就越容易识记。 相似文献
98.
学校改革——这是历史发展的必然规律的体现。教育是为了使人适应生活而培养人的,而生活又在不断地发展,它对人的要求也在不断地变化,因此,教育也应当不断地变化。这一改革将根据本世纪末、下世纪初发达的社会主义社会对学校教育的要求来进行。 相似文献
99.
One hundred nonpatient adults, screened for evidence of personality disorganization, were retested after a three-year interval to study the temporal consistency of the Rorschach. In general, the correlational analysis for 19 basic variables studied, and a directionality analysis for five ratios, illustrate a considerable sturdiness over time. It is postulated that these variables can be separated into situational related indices (state variables), and more stable scores indicative of durable response styles (trait variables), based on the assumption that variables with lower correlations would identify state variables, while the higher correlations would signify the trait features. Nine of the 19 variables yield retest correlations in excess of. 相似文献
100.
六十年代中期,资本主义国家里出现了一场意识形态的运动,七十年代正式形成,此后不断扩大。这场运动基本上是以对马克思的经济学的主要著作《资本论》、《政治经济学批判大纲》的理解为基础,同时又是对马克思的著作,特别是对马克思的早期著作所作的人道主义-存在主义的解释的反映。 相似文献