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921.
Although current theories of memory emphasize the fact that learning is an active process, there is little consensus on the role of active learning. This paper attempts to provide a more precise characterization of active learning in the acquisition of computer skills. The analysis of verbal protocols suggests that active learning varies on at least two dimensions: schema orientation and learning strategy. Schema orientation refers to the type of information the learner is acquiring and varies from relational information to procedural information. Learning strategy describes how the information is acquired. Some people prefer to be internally driven and form their own plans for learning. Others are externally driven and allow the instructional materials to guide their learning. These differences need to be taken into account in describing learning and in designing instructional materials.  相似文献   
922.
Although the typicality effect has been much studied in the semantic memory literature, typicality ratings exist for exemplars from only a very limited number of categories. This lack of ratings frequently limits the range of stimuli that can be used in investigations of the typicality effect. As an aid in stimulus construction, this paper reports typicality ratings of 893 exemplars from 93 different categories.  相似文献   
923.
An electronic device for detecting movement in small animals is described. The principle involves assessing changes in resistance between pairs of grid bars in a cage. The device is inexpensive, sensitive to movement, easy to calibrate and install, reliable across different activity arenas, and indifferent to animal size.  相似文献   
924.
The concepts of informed consent and surveillance of human research designed to protect human subjects is commendable. The regulations of the Institutional Review Board (IRB) are having a major impact on clinical cancer research. There is greater administrative time needed of the investigator, the mechanisms of patient care have become cumbersome and some patients reject optional medical management that could be life saving. IRB regulations must be flexible to meet the needs of human subjects as well as those of the clinical investigator.  相似文献   
925.
A radiotelemetry system for continuous monitoring of the temperature and/or location of small animals is described. All the functions of system control are carried out by an on-line microcomputer (TRS-80 Model III), resulting in a versatile system capable of alternating recording the temperature/location of multiple subjects with other behavioral or physiological events, such as activity level. We describe the use of this system in monitoring body temperature in hamsters and in recording the incubation pattern of breeding ring doves.  相似文献   
926.
Prior surgical implantation of a venous catheter sensitized rats to coldimmobilization stress. Three of six catheterized females succumbed during the stress. The remaining rats fell into two groups in terms of their core temperature at the end of the stress period: Male uncatheterized rats had higher temperatures than rats in the other three groups. No relation was found between catheter patency and magnitude of hypothermia. Degree of gastric disease paralleled the core temperature findings in that the male uncatheterized rats had significantly fewer gastric erosions than the rats in the other three groups. Additionally, a robust effect of gender was found with uncatheterized females showing more hypothermia and more gastric disease than uncatheterized males. A subsequent experiment was conducted to evaluate whether anesthesia or wearing the protective spring was responsible in part for the sensitization seen. Here, the gender difference was less although females consistently averaged lower core temperatures after stress than did males. Despite similar core temperatures after stress, females that were prepared with the protective spring apparatus developed more gastric disease than female controls or similarly treated males. Thus, the additional sensitization exhibited by females in the first experiment may relate to the fact that both catheterization and the taping procedure were sensitizers while only catheterization was a sensitizer for males.  相似文献   
927.
928.
The present study examined some previously reported relationships between drug use by adolescents and perceived attitudes and behaviors of their parents. An anonymous questionnaire was administered to the student body of an inner-city secondary school for difficult students. Relationships between parental use of drugs and adolescent use of the same drugs were moderate and roughly equivalent across drugs. However, parental use of marijuana was strongly related to the adolescent's use of other, harder drugs such as opiates, cocaine, amphetamines, and barbiturates. This finding is explained within the framework of Kandel's postulated stages of drug initiation. It points to a need for further study of parental influences, which may be increasingly problematic as more individuals who have grown up in our marijuana-accepting society become parents of adolescents.  相似文献   
929.
The relationship between the availability of visual information and attention demands during the production of a discrete motor act was examined. Subjects were required to move a linear slide a distance of 15 cm in both 150 and 600 msec conditions under three light manipulations, viz., light always on; light always terminated as movement began; or, subject was unsure as to whether light would stay on or terminate. A simple key press by the index finger of the opposite hand to a tone was used as a secondary task and a measure of attention demands. The light manipulation influenced attention demands on the rapid 150 msec movement such that more attention was demanded when the subject knew the light would terminate. No such attentional strategy differences were found with the slow 600 msec movement. These findings suggest that task constraints in the form of kinematic criteria, together with the perceived availability of visual information, contribute to determining attentional strategy in movement production.  相似文献   
930.
This study tested aspects of Super's self-concept theory of career development with a sample of British schoolchildren. Findings suggested that self-concepts and concepts of occupational preferences do have a role in career development, though there were some indications that the theory is more applicable to more able youngsters and to those high in self-esteem, than to others. Agreement between ideal-self-concepts and occupational preference concepts was significantly greater than that between actual-self-concepts and occupational preference concepts. This finding was interpreted as reflecting the youngsters' greater concern for the future and the possible, rather than the present and the given, and it suggested that refinements are needed in Super's theory.  相似文献   
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