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951.
In southern China, the use of mobile phones is becoming a ubiquitous part of everyday life for young migrant workers. What could be the possible relationship between mobile telephony and job mobility among migrants? A study of 655 migrant workers conducted in 2006 in the Pearl River Delta found a relationship between job change among migrant workers and the increasing use of mobile phones due to more information on jobs with better pay and working conditions being sent to them by friends, former coworkers, and clansmen. However, this portrait of migrant worker e-actors operating in a “broadband information society” can only be viewed in the context of the migrant labor shortage in southern China since 2004. Of fundamental concern are the vagrant identities of this new generation of young migrant workers who are excluded from the host society in which they work but also feel uncomfortable with their farmer status in their home towns.  相似文献   
952.
953.
Epidemiological research indicates that sildenafil (Viagra) abuse is associated with increased risk behaviors. The present study employs the open field, a standard animal model used in the field of anxiety research, to examine whether chronic exposure to sildenafil affects anxiety and risk-taking behaviors in gonadally intact and castrated male Wistar rats. Sildenafil (10 mg/kg) or saline were administered three times a week for three weeks. Animals were tested once a week in the open field during and after drug treatment. Sildenafil treatment increased the number of center entries and time spent in the center in intact and castrated animals during and after treatment, suggesting that repeated drug use decreases anxiety. Sildenafil also restored the deficits in exploration and locomotion produced by castration, indicating that sildenafil effects on open field behaviors are independent of endogenous androgens. We caution against generalizing from this study to human behaviors, but propose that the behavioral effects produced by a chronic high dose of sildenafil warrant further studies into its abuse potential.  相似文献   
954.
In the last few decades, Spain has witnessed a slow but progressive change in predominant family models. The purpose of this work is to advance in our knowledge of stepfamilies through the perspectives and experiences of two of their members, the stepfather and the stepmother. The theoretical model examined in this investigation proposes that stepparents' role strain could have negative effects on their psychological wellbeing. It also proposes that a satisfactory couple relation could mediate in the relation between role strain and psychological wellbeing. In this study, participants were 116 stepparents who had been living for at least one year with their partner. The most relevant results showed the adequacy of the proposed model and the higher vulnerability of stepmothers in these family structures.  相似文献   
955.
In this paper, the development and results of a program are presented, carried out with students in 3rd and 4th grade of primary school, 128 children aged from 8 y 10 years old, 75 assigned to the experimental group and 53 to the control group. In order to assess the changes achieved and whether they were maintained, a pre- and post-treatment Likert-scale of adjectives describing discapacities and a 3-year follow-up measure were applied. As in the previous applications of the program, the results suggest the efficacy of the program, that is, positive changes were achieved in the rating of terms related to disability as well as in the attitudes towards disabled people and these changes were maintained throughout the follow-up. In order to test their influence on attitudes, some variables considered determinants of attitudes toward disability were also contrasted, such as gender, age, acquaintance and experience with the topic of disability, disabled children's integration, and disability type.  相似文献   
956.
957.
The present study examined the relationship between achievement and social goals, and explored how both types of goals can affect secondary school students' persistence/effort in Physical Education classes, as well as their intention to participate in sport activities after finishing secondary school. A sample of 350 students (aged 15-17) from two high schools in Asturias participated in the study. Multiple regression analysis showed: a) persistence/effort in physical education classes was better explained by social responsibility goals, followed by mastery-approach goals and mastery-avoidance goals; b) achievement goals are the only predictors of young people's intention of practicing sport in the future. Differences were found in these results according to gender and course. These findings help us better understand the processes involved in Physical Education. Finally, implications to improve classes and to achieve young people's more active and higher level of implication in sports are discussed.  相似文献   
958.
An association between severe iodine deficiency and poor mental development has been found in many studies. We examined the relationship between moderate or mild iodine deficiency and intellectual capacity in order to determine whether problems common to severe iodine deficiency (including mental retardation) also emerge in a more subtle form. We also wished to know whether the classic methodology (comparing iodine-deficient zones with nondeficient zones) is the most adequate, and propose to combine this grouping by zones with urinary iodine presented by individuals in each zone. We measured IQ, manipulative and verbal capacity, attention, visual motor ability and disruptive behaviour, variables that have barely been studied in this kind of investigations. The sample comprised 760 schoolchildren from the province of Jaén (southern Spain). Our results show that children with low levels of iodine intake and with urinary iodine concentration lower than 100 microg/litre had a lower IQ and displayed more disruptive behaviour than children with high levels of the criteria. The other variables were not associated with iodine deficiency.  相似文献   
959.
The aim of this study was to analyze the relationship between the consumption of alcohol among adolescents and that of their close model figures. The sample was made up of 536 secondary students from rural areas. Predictive models of alcohol consumption were established by means of logistic regression analysis and the criterion used was the consumption by parents, siblings, and the adolescent's best friend. It was observed that alcohol use of these models conditioned the adolescents' consumption; their attitude towards the drug, their intention to consume, their normative perception and perception of risk. The analysis revealed that the main predictor of alcohol use is the consumption by the best friend (OR = 13.04, IC 95% = 8.14-20.91), followed by the consumption by siblings (OR = 1.85, IC 95% = 1.12-3.04). The intention of consumption increases when the father is an alcohol user (OR = 2.70, IC 95% = 1.68-4.36), sibling (OR = 2.83, IC 95% = 1.56-5.15), and mainly best friend (OR = 4.33, IC 95% = 2.55-7.36).  相似文献   
960.
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