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101.
102.
The effects of maternal cigarette smoking during pregnancy on behavioral and physiological measures of arousal were examined in a sample of 50 neonates. After the effects of alcohol, caffeine, and maternal demographic variables were statistically controlled, regression analyses showed that maternal smoking during pregnancy was predictive of higher heart rates overall and during quiet and active sleep. Maternal smoking during pregnancy was also predictive of lower heart rate variability and an increased number of tremors and changes in behavioral state. These findings suggest that maternal cigarette smoking during pregnancy affects the regulation of spontaneous autonomic activity in neonates.  相似文献   
103.
In our complex, interdependent world, it is critical that educators prepare students for global citizenship. One way to develop students’ awareness and understanding of the world is through global literature. Through exposure to this type of literature, students gain multiple perspectives and learn about the social, political, and moral conditions under which people around the world live. They also develop respect and understanding of socially and politically oppressed peoples and learn why it is important to promote social justice. The authors discuss global literature for elementary students and describe an example of a lesson taught in a third-grade classroom using these books. Finally, the authors share the outcomes of the lesson based on their observations and analysis of the students’ oral responses and written reflections.  相似文献   
104.
Abstract

Lester and Perez1 have suggested that student behavior can be usefully construed in terms of a traditional-hedonic, implicit value system. They demonstrated that drug use and sexual activity provide simple behavioral anchors for this dimension, and observed an increasingly hedonic orientation among students. Ten years after their initial study, the student population at the same institution was again sampled using an anonymous questionnaire. The 1980 sample included 208 subjects, and these were compared with 688 subjects who responded to the 1970 survey. This comparison was supplemented by an intensive week-long study of 53 students within one campus living unit.

Significant increases in pre-college sexual activity were noted for both men and women. Marijuana use in high school also increased for both men and women during this period, while alcohol use increased only among women. Previously observed differences between male and female pre-college sexual activity and marijuana use had largely disappeared by 1980. Significant increases in sexual activity while in college were found for women but not for men. For men, overall marijuana and alcohol use in college did not change during the study period, but there was an increase in the frequent use of these drugs. Increases in all categories of marijuana use were noted among women, along with overall increases in their alcohol use. The significant differences between male and female marijuana use noted in the 1970 study were absent in 1980. The intensive week-long study revealed that alcohol use was part of the daily lives of one-third to two-thirds of the students sampled, although they reported interpersonal conflicts, absences from class, accidents, and injuries among the consequences of their drinking. A significant inverse relationship between sleep and alcohol use was observed among women, but not among men.

These data suggest that student behavior has become increasingly hedonic during the past ten years, with women in particular closing the gap which previously differentiated their behavior from that of their male peers. Institutions of higher learning must take these changes into account in the planning of academic programs, residential life, and health services.  相似文献   
105.
In some crossover experiments, particularly in medical applications, subjects may fail to complete their sequences of treatments for reasons unconnected with the treatments received. A method is described of assessing the robustness of a planned crossover design, with more than two periods, to subjects leaving the study prematurely. The method involves computing measures of efficiency for every possible design that can result, and is therefore very computationally intensive. Summaries of these measures are used to choose between competing designs. The computational problem is reduced to a manageable size by a software implementation of Polya theory. The method is applied to comparing designs for crossover studies involving four treatments and four periods. Designs are identified that are more robust to subjects dropping out in the final period than those currently favoured in medical and clinical trials.  相似文献   
106.
Student volunteers at the U.S. Naval Academy (USNA) participated in one of the following one-shot games: a dictator game, an ultimatum game, a trust game, or a prisoner's dilemma game. We find limited support for the importance of personality type for explaining subjects’ decisions. With controls for personality preferences, we find little evidence of behavioral differences between males and females. Furthermore, we conclude that seniority breeds feelings of entitlement—seniors at USNA generally exhibited the least cooperative or other-regarding behavior.  相似文献   
107.
108.
An image that is mapped into a bit stream suitable for communication over or storage in a digital medium is said to have been compressed. Using tree-structured vector quantizers (TSVQs) is an approach to image compression in which clustering algorithms are combined with ideas from tree-structured classification to provide code books that can be searched quickly and simply. The overall goal is to optimize the quality of the compressed image subject to a constraint on the communication or storage capacity, i.e. on the allowed bit rate. General goals of image compression and vector quantization are summarized in this paper. There is discussion of methods for code book design, particularly the generalized Lloyd algorithm for clustering, and methods for splitting and pruning that have been extended from the design of classification trees to TSVQs. The resulting codes, called pruned TSVQs, are of variable rate, and yield lower distortion than fixed-rate, full-search vector quantizers for a given average bit rate. They have simple encoders and a natural successive approximation (progressive) property. Applications of pruned TSVQs are discussed, particularly compressing computerized tomography images. In this work, the key issue is not merely the subjective attractiveness of the compressed image but rather whether the diagnostic accuracy is adversely aflected by compression. In recent work, TSVQs have been combined with other types of image processing, including segmentation and enhancement. The relationship between vector quantizer performance and the size of the training sequence used to design the code and other asymptotic properties of the codes are discussed.  相似文献   
109.
SOCIAL ATOMISM, HOLISM, AND TRUST   总被引:3,自引:0,他引:3  
The metatheoretical difference between social atomism and social holism is clarified by analysis of the generic necessity of trust. A theoretical approach to trust can be traced from Durkheim, Simmel, Parsons, and the recent work of Luhmann and Barber. Trust functions as a deep assumption underwriting social order and is not reducible to individual characteristics. Changes in trust alter social relationships. The study of power, exchange, family, and politics illustrates how trust constitutes social reality as emergent and holistic. This helps us understand the formation of interpersonal relationships, the difference between economic and social exchange, and the discrepancy between attitudes toward society and toward particular institutional actors.  相似文献   
110.
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