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31.
Cerebral activity, as reflected by power in the alpha waveband (8-13 Hz), was examined prior to the performance of three tasks with different effort and accuracy requirements. The study aimed to further investigate changes in activity observed in an earlier study in which expert karate performers exhibited significant increases in alpha band power during preparation for a training task. In contrast to the earlier research, the high effort task produced a significant decrease in 'alpha' power prior to performance. 'Alpha' power prior to the high accuracy task showed significant differences mediated by the outcome. Successful performance was preceded by higher levels of 'alpha' power than unsuccessful attempts. The reported use of a cognitive strategy on the first task produced a significant difference in activity, lower alpha power being associated with the use of such a technique.  相似文献   
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New World Writing, a magazine founded by New American Library in 1952, quickly became an important vehicle for liberal intellectual and literary thought. In addition to providing an outlet for new writing, the magazine became an important acquisitions tool for NAL. Throughout its lifetime, New World Writing remained a showcase for many of the finest writers of the 1950s, including Christopher Isherwood, Louis Auchincloss, Tennessee Williams, Flannery O’Connor, Jack Kerouac, and Gore Vidal. He is the author of Under Cover: An Illustrated History of American Mass Market Paperbacksand Heavy Traffic and High Culture: The New American Library as Literary Gatekeeper. He is working on a study of American literary agents  相似文献   
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This paper examines end-user, online searching using data from a questionnaire mailed to 150 Canadian health professionals in practice settings. The response rate was 83% (n = 124). The data provide a demographic profile of early adopters of end-user searching in the health care community. Positive correlations with the user's level of implementation of end-user searching were found for the following variables: amount of time spent in research activities, amount of system training received, and use of Medical Subject Headings (MeSH). There was a negative association between the amount of time spent in patient care and implementation level. General practitioners and family physicians had lower implementation levels than physicians in other specialties. Successful implementers were more likely to be computer literate and to place a high value on formal information sources such as books, journals, and libraries. Health professionals using so-called "user-friendly" or menu-based software had lower levels of personal commitment to using online databases, as measured by a combination of continuance of use, willingness to pay personally, type of recommendations made to colleagues, and hardware ownership.  相似文献   
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The research discussed in the present paper, set out to find how a sample of Singaporean adolescents perceived and managed different sources of stress. The sample totalled 212 pre-university students with equal numbers of boys and girls, and a mean age of 17 years 5 months. The students attended a number of junior colleges in the republic, with the sample ethnicity reflecting national proportions. Measures of stress included Behaviour Profile, Life Events, School Stress Factors, Home-School Stress Conditions and Stress Symptoms. All measures were administered as questionnaires.

The results showed that several features of Type A behaviour emerged and that school examinations, job aspirations, school work and homework were the principal stressors. Fear of the unexpected, exhaustion and lack of concentration were the most quoted stress symptoms. Science students appeared to be more stressed than arts students.

Among the main management strategies employed by these adolescents at home, were listening to music, reading and exercise, while stress in school was managed through self control, self-sufficiency and sharing problems with peers. In the main, most students seemed to be able to cope by adapting to stressful situations as they arose at a particular time.

Some of the more important implications of the above findings are discussed in the context of schooling in Singapore and in the wider context of society.  相似文献   

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This study was designed to examine children's attitudes toward the role of sports in determining social status, as well as the activities in which children prefer to participate. A total of 227 boys and 251 girls in Grades 4, 5, and 6 completed a questionnaire to determine which criteria were most important in determining personal, female, and male popularity. Personal popularity was answered by the girls and boys according to "what would make you well liked by your classmates." Female and male popularity was determined by asking both girls and boys to decide "what would make (girls, for female subjects, and boys, for male subjects) well liked by your classmates." A comparison of results from the Buchanan, Blankenbaker, and Cotten (1976) investigation and the present study indicated that, in the last 15 years, appearance has become more important and academic achievement less important in determining personal popularity for girls. For boys, the comparison revealed that sports have become more important and academic achievement less important in determining personal popularity. Boys reported sports to be the most important determinant of personal and male popularity and appearance as the most important determinant of female popularity. Sports and appearance became more important for boys with each higher grade level. Girls reported appearance to be the most important determinant of personal, male, and female popularity. For girls, appearance became more important with each higher grade level. A comparison of results from the Buchanan et al. (1976) and the present study indicated that the activities in which girls and boys preferred to participate have changed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The Alfred Taubman Medical Library at the University of Michigan has offered instruction in online literature searching to third-year pharmacy students as a component of the course "Drug Information and Scientific Literature Evaluation" since 1983. In the spring of 1989, a follow-up study was conducted to assess the impact of instruction on four classes of graduates. Of a pool of 151 graduates, 90 (60%) responded to a mailed questionnaire on their use of information and computerized literature searching. The respondents were divided into four subgroups: end-user searchers, users of intermediaries, end users who used intermediaries, and those who did not use computerized literature search systems. Seventy-two percent of the respondents used some type of computerized literature searching, and 42% performed their own searches. The four subgroups differed in general computer use, familiarity with MEDLINE search terminology, information use, reasons for using or not using literature searching, and characteristics of searches (i.e., type, time frame, amount, and frequency). Training in end-user search systems appears to have had an impact on the continued use of computerized literature searching several years after the formal educational program.  相似文献   
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