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941.
This prospective study examined the usefulness of seven selected variables from Jessor and Jessor's problem behavior theory in predicting the future smoking levels of adolescent experimental smokers. Experimental smokers were identified through a survey of 2,550 seventh- and eighth-grade students assessing subjects' current smoking levels as well as subjects' responses to the selected variables. Twelve months later the entire sample was resurveyed to assess subsequent smoking levels of subjects initially reporting experimental smoking. Experimental smokers who responded to both surveys (n=225) were subjects of the present study. The full model discriminant function was significant in discriminating between the two groups; 68% of the subjects were correctly classified. This moderately successful hit rate was 24% better than what could be expected by chance. Increased smokers had lower expectations for academic achievement, had stronger beliefs about the positive functions of smoking, and perceived more smoking among their classmates and close friends. Educational interventions are suggested.Received Ph.D. from the University of Nebraska in 1987. Research interests include human behavior change strategies.Received Ph.D. from University of Illinois in 1968. Research interests include behavior and health. 相似文献
942.
ROSS M. MARTIN 《澳大利亚政治与历史杂志》1985,31(2):269-281
943.
944.
The stepping-stone theory of progression into drug use is examined, based on the alcohol and other drug use of over 27,000 seventh-through eighth-grade students in New York State. The data show that students do not use illicit drugs unless they also use alcohol. White, black and Hispanic students all tend to initiate the use of drugs in the following order-alcohol, marijuana, pills, and hard drugs. Among blacks and Hispanics, pills are not as important a transition between marijuana and hard drugs as they are among whites. Cigarettes form an important step between alcohol and marijuana use for younger students, particularly for females. Since alcohol serves as the gateway to all other drug use, prevention approaches that control and limit alcohol use among adolescents may be warranted.He received his Ph. D. in Psychology for the State University of New York at Buffalo in 1976. His research interests are the social and psychological correlates of drinking.She received her Ph.D. in Sociology from the State University of New York at Buffalo in 1983. 相似文献
945.
Stuart T. Hauser Wendy Liebman John Houlihan Sally I. Powers Alan M. Jacobson Gil G. Noam Bedonna Weiss Donna Follansbee 《Journal of youth and adolescence》1985,14(4):317-337
This study examined the influence of pubertal timing upon family interactions in normal and psychiatric adolescent samples. An important feature of our approach is its emphasis upon micro-analysis of family behaviors (individual speeches) and family processes (theoretically specified speech pairings). Rather than assume that global family patterns (e.g., power) shift in response to pubertal changes, we follow how types of speeches and speech sequences are associated with different pubertal timing. Using the previously constructed family coding system, the Constrainig and Enabling Coding System, we found that on-time adolescents and their parents differed from both off-time groups (early or late). These results are discussed in terms of current implications and suggestions for future research.An earlier version of this paper was presented at the SRCD Study Group on Timing of Maturation, October, 1983, at the Education Testing Service, Princeton, NJ. This research was supported by NICHD Grant 1 R01 HD18684-01, and an NIMH Research Scientist Award (Dr. Hauser).Received his Ph.D. from Harvard University. Research interest is adolescent development within the family and impact of chronic illness on adolescent development and family interaction.Received her B.A. from Wellesley College. Research interests are in humor and attractiveness.Received his M.A. from Boston University. Research interests are in methodology and statistics.Received Ed.D. from Harvard University. Research interests are in adolescent development within the family, and family coping with stress.Received M.D. from University of Chicago. Research interests are in psychosocial aspects of diabetes.Received Ed.D. from Harvard University. Research interests are in developmental psychopathology, and moral and ego development.Received Ph.D. from Ohio State University. Research interests are in assessment of ego development and family systems.Received Ph.D. from University of Miami. Research interests are in family studies and adolescent development. 相似文献
946.
Bruce E. Compas Lesley A. Slavin Barry M. Wagner Kathryn Vannatta 《Journal of youth and adolescence》1986,15(3):205-221
Relationships among major life events, perceived social support, and psychological disorder were assessed in a sample of older adolescents. Negative life events and satisfaction with social support were significantly and independently related to a range of psychological symptoms. Further, the relationship between negative events and disorder was moderated by gender, the types of events experienced, and anticipated change in the psychosocial environment. The importance of the use of standardized and psychometrically sound measures of life events, social support, and psychological disorder is highlighted.Received his Ph.D. from UCLA in 1980. An assistant professor, he is currently investigating stress and coping among children and adolescents.Received her Ph.D. from the University of Vermont in 1985. An assistant professor, she is currently studying social support.Received Ed. M. from Harvard Universtiy. He is a doctoral student in clinical psychology interested in the role of social support in coping with stress during adolescence.Received her BA from the University of Vermont. She is a doctoral student in clinical psychology. 相似文献
947.
Over the past two decades states have significantly increased their use of competitive bidding to purchase health and social services from private agencies. Competitive contracting is thought to facilitate program administration, to reduce costs, and to increase the quality of delivered services. We evaluate these claims in light of Massachusetts' experience with competitive contracting for mental health care. We find that few of the expected benefits are achieved. In practice, supposedly competitive bidding systems often degenerate into administratively complicated negotiations between the state and private monopolies. This results in higher costs and lower quality of services. In light of this negative assessment, three strategies for reform are proposed and evaluated. 相似文献
948.
949.
Sixty-eight college students listed the factors they consider or would consider when making the following commitments: choosing courses, choosing a major, choosing a career, choosing a friend, choosing a romantic partner, and choosing a lifelong partner. In addition, subjects provided their own definition ofcommitment in an unstructured essay. Subjects listed more factors, more distinct types of factors, and more original factors for interpersonal commitments than for academic/vocational commitments. There were few gender differences found in these measures, contradicting the idea that men and women think differently about different commitments. In addition, few gender or class year differences were found in the themes present in the essay definingcommitment. Conceptions of commitment, as described in essays, predicted thinking about specific commitments only slightly.Received Ph.D. in Psychology and M.S.E. in Computer Science from the University of Pennsylvania, and has research interests in the areas of cognitive development and reasoning and decision making.Received Ph.D. in Counseling and Guidance from the University of Wisconsin, Madison, and has research interests in adolescent development and adolescent psychopathology. 相似文献
950.
A. S. M. Abdul Matin 《Policy Sciences》1987,20(1):99-103
In an attempt to delay hatching without affecting their viability, the eggs ofLatheticus oryzae W. were subjected to cold treatment at 5° for varying periods and at different stages of their development. A small dose
of 0.5 krad of gamma radiation was also given at each of those temperature treatments. Most of the eggs hatched at 30° following
low-temperature exposures of 1 and 2 days. There was a significant decrease in hatch as the exposure period increased further
(P<0.05). An egg exposure to 5° also led to an increase in egg period and the increase was nearly equal to the period of cold
exposure. Radiation did not alter the situation.
Zusammenfassung Kühllagerung ist eine der gebr?uchlichsten Methoden für die Aufbewahrung von Insekteneiern. Um die optimalen Bedingungen für eine Vorratshaltung zu bestimmen, wurden 0–1 d alte Eier vonL. oryzae Temperaturen von 5° w?hrend 1–7 d ausgesetzt, nachdem sie verschieden lange bei 30° gehalten waren. Eine kleine Dosis von 0.5 krad Gammabestrahlung wurde bei jeder Temperaturbehandlung ebenfalls gegeben. Alle Eiproben wurden nach den verschiedenen K?ltebehandlungen in 30° zurückgebracht und die Wirkung auf Schlüpfprozentsatz und Eidauer bestimmt. Die Eidauer nahm zu, wenn die Eier bei 5° gehalten wurden, was anzeigt, da? die Embryogenese bei 5° unterdrückt wurde. Die Lebensf?higkeit der Eier wurde nicht beeintr?chtigt bei einer 5°-Einwirkungsdauer von 2 d, nahm aber bei weiterer Verl?ngerung der Expositionsdauer ab. Nur etwa 37% der Eier schlüpften (44,1% der Kontrolleier) nach 7-t?giger K?ltebehandlung. Bestrahlung beeinflu?te weder das Schlüpfen noch die Entwicklungsdauer.相似文献