西部大开发要充分考虑生态安全环保政策

中国西部开发,首先要把现有的适用技术加以系统集成,大力示范推广.其中重要的是积极推动环境的资源保护政策,加强西部地区生态建设,走可持续发展之路,决不能以牺牲环境为代价.要落实之,必须先思考生态安全环保政策.     

Predictability of social connections over time

A developed theory of social networks would potentially provide predictive and explanatory models for social processes at the most general level. The paper contributes to such a theory by elaborating one basic proposition: that social connections attract each other as a regular function of network parameters such as ‘structural strength’ (number of common links) and ‘distance’ (length of minimal path of linkage). The proposition is tested on longitudinal data from three locality-based networks.     

The determinants of strikes over time and across industries

This paper presents a pooled time-series, cross-section analysis of strike activity across 27 major industry groups over the years 1970–1980. While numerous studies have analyzed the time-series behavior of strike activity and fewer studies have analyzed the cross-sectional pattern of strikes, little work has been done to combine both perspectives into one empirical analysis. This paper improves on this by incorporating variables into one regression model that is capable of explaining both dimensions of the variation in strike activity. The regression results suggest that strikes over time and across industries are affected by a wide range of economic, organizational, institutional, occupational, demographic, market structure, political, and other variables.     

Social conservatism: Determinants and structural stability over time

The decade of the 1970s is generally regarded as one of increasing conservatism in attitudes and lifestyle. Using general social survey data from the period 1972–1980 the paper describes and explains some of the fundamental shifts in socially conservative attitudes (i.e. attitudes concerning civil liberty, abortion, racial segregation) which occurred during the 1970s. Findings suggest the following: (1) attitude structures changed little over time; (2) levels of conservatism showed a statistically significant increase over the decade; (3) the overall explanatory structure (both slopes and intercepts) changed over the time period investigated. However, levels of education and levels of church attendance had consistent (but inverse) impacts on degree of conservatism; (4) size of place of current residence was conspicuously absent as an important predictor. Since this is the most often used proxy for rural vs urban milieu, we encourage caution in interpreting much of the literature on rural-urban differences.     

Migrant visits over time: Ethnographic returning and the technological turn

This paper reflects on four decades of research (via ethnographic returning) to explore the social transformations in travel and communication technologies that have impacted the lived experiences, and consequently the theoretical conceptualization, of migrant visits. A comparison of migration waves between Italy and Australia reveals both continuities in visiting experience as deeply relational practices that facilitate a mutuality of being, but also transformations brought about by the technological turn. Visits take on different meanings depending on individual/ family life stage, generation, and community and national histories. The capacity for both physical and virtual copresence must be understood as coconstitutive, requiring a temporal perspective. The experiences of immobile migrants in residential care suggest that, in the context of rich histories of copresence over time, digital kinning can provide the capacity to share a mutuality of being that safeguards the socio-relational ties of individual and collective identities and belonging that make us human.     

The effects of gainsharing on grievance rates and absenteeism over time

We sought to better understand the long-term impact of gainsharing by analyzing longitudinal changes in two key indicators of workplace union-management relations: grievance rates and employee absenteeism. Using a seven and one-half year longitudinal data set and an interrupted time series design, we found that the introduction of a Scanlon-type gainsharing plan was followed by a gradual and permanent decline in both of these indicators. These results provide strong quantitative evidence for the ability of gainsharing to transform existing labor-management relations. Using qualitative data, we consider the relationship between labor relations outcomes and other plant-level performance improvements following the introduction of gainsharing in this case.     

School experiences of pupils with physical impairments over time

This article focuses on the experiences of seven youths with physical impairments within primary and secondary school. Overall, participants considered secondary school to better accommodate their needs, although limited accessibility and flexibility complicated their possibilities for participation. The emphasis was not placed on the completion of educational activities, but rather on whether or not the pupils had the opportunity to engage in selected activities alongside their peers and were actively consulted in the implementation of these activities. The stability versus change in the views of the youths was of interest, especially how they interpreted certain school experiences compared with when they were younger.     

A preventive services program model for preserving and supporting families over time

Selected findings from a three-year study are reported regarding a prospective sample of 189 families served by the Center for Family Life's preventive services program and the nature and results of the services the families received. The program combines elements of both family preservation and family support services to provide a comprehensive, individualized response to families in need and prevent the unnecessary placement of children in care. Four program elements correspond with those typically identified as characterizing family preservation programs, and three key program elements differentiate the Center's approach from other family preservation programs. These latter characteristics are more typically found in family support programs and address limitations of current family preservation programs as identified in the literature.     

Pareto optimality in spatial voting models

This paper studies the Pareto optimality properties of policy proposals that are made byk(k2) strategic candidates that face uncertainty about the choices that the voters will make. Our first theorem shows that, under very general conditions, any proposal that is a best reply for a candidate is necessarily Pareto optimal. This theorem, in turn, implies that, under slightly stronger conditions, all candidate proposals that are made in a Nash equilibrium or sequentially are necessarily Pareto optimal. Our second theorem shows that, when these conditions are themselves slightly strengthened, any proposal outside of the Pareto set is strictly dominated by at least one proposal inside the Pareto set.We would like to acknowledge helpful comments and suggestions provided by Otto Davis and Richard McKelvey     

The value of opportunities over time when preferences are unstable

Most work on measuring opportunity is directed at ranking opportunity sets. This paper addresses the more general issue of assessing the opportunity provided by multi-period decision problems, focusing on the dynamic inconsistencies that can occur if agent’s preferences are unstable. A principle is proposed by which a dominance relation among outcomes iteratively induces a dominance relation among multi-period problems. This principle implies that opportunities to make sequences of individually reasonable actions have positive value, even if, because of dynamic inconsistency, those sequences lead to unambiguous loss. Opportunities which allow an agent to constrain herself are shown to have zero value.     

Evaluating the self-expressed unmet needs of emancipated foster youth over time

This study explores the self-reported unmet need for independent living services of young people making the transition to adulthood from foster care after the creation of the Chafee Foster Care Independence Program. We find that 34.5% of youth indicated that they had an independent living service need that went unmet at age 17, 27.9% at age 21 and 35.5% at age 23, with the largest percentage indicating they lacked preparation in the area of finance. Some of these youth expressed unmet need consistently while others' expression of unmet need fluctuated over time. Youth who indicated that they had mental health issues were significantly more likely to report unmet need at baseline and wave 3. Youth who indicated that they received more social support and independent living services were less likely to report unmet need at baseline and wave 3. These youth perspectives could lead to the enhancement of existing independent living skill provision as states prepare to extend the age of foster care benefits, ultimately making them more timely and effective.     

Intensive management reduces butterfly diversity over time in urban green spaces

Urban Ecosystems - Loss and fragmentation of semi-natural grasslands have had negative consequences for grassland biodiversity, such as butterflies. Urban parks and other urban green spaces have so...     

Reports of childhood sexual abuse by adolescents and young adults: Stability over time

The consistency of childhood sexual abuse (CSA) reporting was explored in this study. Two‐hundred seventeen adolescents and young adults (ages 14–24) enrolled in urban health care clinics completed self‐report questionnaires assessing CSA and other problem behaviors at enrollment and at 7 months. Results indicated that the stability of CSA self‐report at two time points was poor (58% consistent nonreporters of CSA, 20% consistent reporters, 22% inconsistent reporters). Consistent and inconsistent reporters were differentiated on risk measures. Adolescents who endorsed more items from the CSA scale were five times more likely to be consistent reporters. In sum, adolescent CSA reporting was quite inconsistent over time. Using multi‐item scales and assessing CSA at two time points enhances accuracy of reporting.     

Realigning criminal policy. Offender and victim in the Swedish party system over time

The article conducts a case study of criminal policy in the Swedish party system between 1960 and the present. Like other countries, Sweden has witnessed its criminal policy take a ‘punitive turn’ during this time. We hypothesize that this turn is explained by the fact that the discourse on crime has become increasingly victim-centred. Our study of the changes in the parties’ policies suggests that the parties play a central role in this explanation. In order to understand the punitive turn, however, the increasingly victim-centred discourse must in turn be explained. We argue that it is the individualization of society which provides the key here.     

The impact of partner stalking on mental health and protective order outcomes over time

The goals of this article are to examine stalking victimization over time among a large sample (n = 662) of women who received a protective order against a violent partner and to examine the impact of stalking on mental health and protective order outcomes. Findings suggest that stalking is a significant risk factor for other forms of partner violence (e.g., psychological, physical, and sexual violence) and that the experience of being stalked by a violent partner contributes uniquely to women's perceptions of psychological distress, personal safety, and perceptions of protective order effectiveness. Both the criminal justice system and victim service representatives need to be vigilant in educating women about the increased risk of stalking to their safety and mental health. Further, study findings suggest that stalking must be addressed to prevent future physical and psychological harm in partner violence cases.