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31.
This 2-year longitudinal study of 302 high school students in the state of Indiana examined attitudes toward the use of alcohol in 25 potentially hazardous settings, varying from riding in a car, to swimming, to simply drinking at home. Student ratings indicated that they were capable of rationally evaluating alcohol-related risks. Principal components factor analysis identified three factors underlying student responses: propensity/desirability of the behavior, choice/control of the risk, and fear/consequences/likelihood of the risk. Each of these factors was comparable to factors found to be important in past studies of adult risk perception. The finding that self-reported behavioral propensity and desirability were weakly correlated with the measures of perceived risk is of particular interest. Attempts to reduce the use of alcohol by adolescents have traditionally focused on risk awareness. The implication of this study is that intervention programs might be more successful if they focused on modifying perceived value.  相似文献   
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The analysis reveals that although cogeneration alone will not resolve power-shortage problems, it could produce more scheme in developing countries. The paper estimates the cogeneration potential in selected countries and identifies the technical, economic/financial and institutional issues of importance to cogeneration development in developing countries. The analysis reveals that although cogeneration alone will not resolve power-shortage problems, it could produce more than a 10% increase in the electricity-generation capacity in developing countries. Most of this potential is in the industrial sector and can be economically developed.  相似文献   
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A (14;21) homozygous Robertsonian translocation was detected by first-trimester prenatal diagnosis. The related parents were heterozygous for the same translocation. At birth the baby was physically normal and had a normal psychomotor development. Together with a few previous observations in living homozygotes for (13;14) translocations, this case corroborates the idea that these subjects with 44 chromosomes are healthy without dysmorphic features.  相似文献   
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Charcot-Marie-Tooth disease type 1A (CMT1A) is a frequent hereditary motor and sensory neuropathy of the peripheral nerves. In most cases, the disease is associated with a 1.5 Mb tandem duplication at 17p11.2. A 42-year-old pregnant woman requested prenatal diagnosis because of her age and since both her husband and two children were severely affected with CMT1. The CMT1A duplication was demonstrated in the father's, the two children's, and the fetus's DNA using different molecular genetic methods. Although cytogenetical analysis showed a normal female karyotype in the fetus, the parents decided to terminate the pregnancy because of the genetic risk associated with the CMT1A duplication.  相似文献   
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Among 1041 pregnancies 13 twin gestations were detected by routine ultrasonography prior to genetic amniocentesis at the Department of Prenatal Physiopathology of the University of Bologna. Clear amniotic fluid from both sacs was obtained in 12 of 13 sets of twins. All 12 sets were cytogenetically normal with normal levels of α-fetoprotein. Only one patient spontaneously aborted liveborn immature twins 30 days after the procedure. The technique used to obtain samples of fluid is described in detail and the need for additional counselling prior to amniocentesis in twins is stressed.  相似文献   
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This paper offers a new perspective on the environmental laws in Asian nations affecting the exploration, mining, and reclamation activities of the mineral resource industry: the perspective of the senior government officials in those countries, whose job is to enforce these new environmental laws. The article presents the results of a 1998 survey of national environmental officials in Asia conducted by the Colorado School of Mines and the Metal Mining Agency of Japan. Officials in 10 diverse countries—Cambodia, China, Indonesia, Lao PDR, Malaysia, Myanmar, Mongolia, Philippines, Thailand and Vietnam—responded to a detailed questionnaire covering applicable laws, agencies, protected areas, covered mineral activities, financial assurance, environmental impact assessment, public involvement, environmental standards, permit and reclamation requirements.
The survey confirms that Asian nations are part of the global trend towards national government regulatory structures that balance mineral development objectives with environmental considerations. The survey also shows developing regulatory systems (some embryonic, some more mature) utilizing a combination of mining and environmental acts, and often an 'insider' perspective of the national officials administering the laws. While that perspective is not without its biases (not least the rigor of enforcement), it may nevertheless be of use in company planning. The emerging regulatory picture contradicts the conventional notion that it is the 'lower' level of regulation in Asia that is attracting foreign direct investment in mining.  相似文献   
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