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811.
As a field of study, “research utilization” is at a turning point. Despite an accumulation of replicable findings, robust constructs, even a “soft technology” for bridging the gap between theory and practice, we are still largely in the situation of the distance between social problems of, let us say, conflict or inequality and the ability of social science to provide credible, reliable and usable solutions. At the same time, the initial paradigms, suffering from hyperrationalism, have given way to more transactional ones, and have been shaken by the tenets of postmodernism. Shaken, but not undone, as “middle-level” constructs emerge, ones that appear to link the research community with a variety of professional communities in more meaningful and durable ways. Michael Huberman has been Visiting Professor of Education at Harvard University since 1991, where he teaches research methodologies and conducts research on knowledge dissemination. He is also Senior Research Associate at the Network, Inc.  相似文献   
812.
813.
Bravais (1850/1949) demonstrated that there are five types of periodic dot patterns (or lattices): oblique, rectangular, centered rectangular, square, and hexagonal. Gestalt psychologists studied grouping by proximity in rectangular and square dot patterns. In the first part of the present paper, I (1) describe the geometry of the five types of lattices, and (2) explain why, for the study of perception, centered rectangular lattices must be divided into two classes (centered rectangular andrhombic). I also show how all lattices can be located in a two-dimensional space. In the second part of the paper, I show how the geometry of these lattices determines their grouping and their multistability. I introduce the notion ofdegree of instability and explain how to order lattices from most stable to least stable (hexagonal). In the third part of the paper, I explore the effect of replacing the dots in a lattice with less symmetric motifs, thus creating wallpaper patterns. When a dot pattern is turned into a wallpaper pattern, its perceptual organization can be altered radically, overcoming grouping by proximity. I conclude the paper with an introduction to the implications of motif selection and placement for the perception of the ensuing patterns.  相似文献   
814.
Empirical and conceptual developments that led to the formulation of a behavior system for the sexual conditioning of male Japanese quail are described. Initial efforts concentrated on conditioning with localized conditioned stimuli and on identifying behavioral indices of conditioning. Later, learning about species-typical cues and about contextual cues was also explored, and it became evident that different types of cues control different aspects of sexual behavior. The results were used to formulate a behavior system containing both response and stimulus dimensions. In this system, contextual cues and local cues are assumed to elicit only general search behavior unconditionally. In contrast, unconditioned responses to species-typical cues of a female quail include general search, focal search, and copulatory behavior. General search, focal search, and copulatory behavior can become conditioned to local cues. Conditioning can also modify focal search behavior elicited by species-typical cues and can result in various modulatory influences between different types of stimuli. The behavior system approach provides a framework for organizing the diverse sexual conditioning effects and suggests future directions for investigation.  相似文献   
815.
816.
There is a growing awareness of how stress adversely affects organizational efficiency. The implementation of stress management programs to counteract this problem has been slow. This study examined such programs in companies who claimed that they were active and successful in stress management for their employees. The successful features of these organizational stress management programs are identified, discussed, and a model for organizations is presented.  相似文献   
817.
Extensive historical sleuthing reveals that the word "bioethics" and the field of study it names experienced, in 1970/1971, a "bilocated birth" in Madison, Wisconsin, and in Washington, D.C. Van Rensselaer Potter, at the University of Wisconsin first coined the term; and André Hellegers, at Georgetown University, at the very least, latched onto the already-existing word "bioethics" and first used it in an institutional way to designate the focused area of inquiry that became an academic field of learning and a movement regarding public policy and the life sciences. A further comparison of the Potter and the Hellegers/Georgetown understandings of bioethics and the relative acceptance of the two views will appear in the March 1995 issue of this journal.  相似文献   
818.
Outcome following traumatic brain injury (TBI) has been frequently evaluated for adults, although there has been minimal research on adolescents with TBI. It has been argued that TBI sequelae may be more difficult for adolescents to adjust to given developmental changes in physical (puberty), interpersonal (self-concept), and environmental domains (transition to college). In addition, it is commonly acknowledged that moderator variables such as psychiatric history, family functioning, substance use, and sexuality impact functional outcome following TBI, although it is often difficult to objectively evaluate these variables. The current study examined relationships among TBI-related deficits, moderator variables, and academic outcomes for six adolescents transitioning to college. The findings suggest that it may not be appropriate to predict functional outcome based solely on objective neuropsychological results. However, moderator variables appear to have a more direct relationship with outcome, depending on the moderator variable and the individual.  相似文献   
819.
Biotechnological advance is speeding the development of drugs. The approval processes for new drugs will inevitably involve a regulatory agency in making political-economic and scientific choices. Interests of specific patients and the public in general are to be considered, and enormous stakes are involved for companies concerned. A medical regulatory authority must be at once insulated from and responsive to many different mixes of singular and general interests and pressures. Access to new drugs can be spurred by the press of patient advocacy groups, but if there are well organized groups to monitor the testing and approval process for such as AIDS or cancer drugs there is often no similar group to represent patient needs. If there is no organized patient advocacy group, compassionate responsibility by a medical regulatory authority is indeed called for. Delay in the approval of new drugs for fighting severe blood infections raises the question of how to insure the compassionate responsibility of a regulatory authority.  相似文献   
820.
This paper describes a method for generating sample survival distributions from a hypothetical population, as would be required for running Monte Carlo simulations. The method is based on the concept of a quincunx. Cases are entered into a life table and allowed to drop out or die during each interval with probabilities that mirror the hypothetical population. By repeating this process many times and tracking the results, the researcher is able to study the sampling distribution of effect size indices and test statistics, and can generate empirical estimates of power and precision for planned studies. Unlike other methods that are commonly used for this purpose, the model proposed here allows the researcher to define a population in which the hazard rates and/or attrition rates vary substantially from one time point to the next, as may be the case in clinical trials or studies of processing times. The method requires less than 100 lines of code and runs some 10,000 simulations per hour on a microcomputer.  相似文献   
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