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991.
There is a growing consensus among economists that the most procompetitive strategy for restructuring public utility enterprises includes complete vertical separation of the network or grid portion of a sector from other parts of the sector where competition is to be created. Although exceptions to this rule are readily granted, it is generally considered that any alternative strategy may pay a high cost in terms of discriminatory access to the grid by non-integrated entrants into the new competitive sector. This consensus is somewhat surprising in light of the simultaneous growth of transactions cost economics, with its emphasis on the benefits of close vertical relationships—including vertical integration—in the face of complexity, unforeseeable contingencies, and problems with contract law enforcement. These issues are considered in the context of a Russian railways restructuring plan which may, or may not, involve complete vertical separation.
Russell PittmanEmail:
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992.
Investigating the effects of privatization in transition countries is the focus of a large body of current research. Generally, privatization stimulates private sector development, attracts foreign direct investment, fosters competition and contributes to the formation of stock markets. In addition, privatization may improve individual enterprises’ performance. This paper investigates the impact of privatization on Ukrainian firms’ productivity. The empirical research is based on a sample of 466 Ukrainian joint-stock enterprises for the period of 1997–1999. Estimation results indicate that privatization positively influences labor productivity, sales and profitability, but also that these effects diminish over time.
Stefan Lutz (Corresponding author)Email:
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993.
In 1999, the Ontario provincial government introduced into its high school curriculum a requirement that students complete 40 h of volunteer community service before graduation. At the same time, the high school curriculum was shortened from five years to four. Consequently, the 2003 graduating class of Ontario high school students contained two cohorts, the first of the 4-year cohorts that was compelled to complete a mandated community service requirement, and the last of the 5-year cohorts that was not. Using a quasi-experimental design, we surveyed 1768 first-year university students in terms of their perceptions and attitudes about the nature and amount of previous volunteering, attitudes towards community service, current service involvement and other measures of civic and political engagement. Comparisons of the two cohorts indicate that, while there were discernible differences between the two cohorts in terms of their past record of community service, there were no differences in current attitudes and civic engagement that might plausibly be attributed to participation in the mandatory service program. Results are discussed with relation to the current debate concerning the impact of mandatory volunteering policies on intrinsic motivation to volunteer.
Kimberly Ellis-HaleEmail:
  相似文献   
994.
This study examined how youths’ gender is related to the educational expectations of urban, low-income African American youth, their parents, and their teachers. As predicted, African American boys (ages 9–16) reported lower expectations for future educational attainment than did their female counterparts. Parents and teachers also reported lower expectations for African American boys (ages 6–16) than for girls. These findings held even when controlling for academic achievement. Contrary to predictions, the magnitude of the difference in expectations for males vs. females did not increase as a function of youths’ age. In keeping with our hypotheses, parental expectations fully mediated the relation between youths’ gender and youths’ expectations. Finally, certain school-based factors (i.e., positive teacher expectations and positive youth perceptions of the school environment) appeared to protect youths’ expectations from the deleterious impact of low parental expectations.
Dana WoodEmail:
  相似文献   
995.
Prospective associations between violent victimization, the quality of the parent-adolescent relationship, and the subsequent onset of violent aggression were examined. Using the National Longitudinal Study of Adolescent Health (Add Health), participants were divided into violent and non-violent cohorts based on whether they had committed an act of violence prior to Wave 1. Results showed that violent victimization at Wave 1 predicted the onset of violent aggression at Wave 2 for adolescents who were non-violent at baseline. Earlier violent victimization, however, had no effect on aggression trajectories for baseline violent adolescents. Parent-adolescent relations functioned as a protective buffer, such that violently victimized adolescents who reported high quality relationships with parents were less likely to be involved in violent aggression at Wave 2. Subsequent gender interaction analyses revealed that while the buffering effect was evident for males, parent-adolescent relations did not protect females from the onset of aggressive behaviors. Findings are evaluated in light of social learning and cycle of violence theories that highlight the role of violent victimization among adolescents.
Jeffrey T. Cookston (Corresponding author)Email:
  相似文献   
996.
The purpose of the present study was to examine the direct and indirect effects (through peer contacts) of parental knowledge on adolescents’ delinquent and aggressive problem behavior, using latent growth curve modeling. A sample of 457 13- to 14-year old adolescents at first measurement wave (M=13.27; SD=0.45 years) filled out questionnaires about their parents, peers, and problem behavior three times with 1-year intervals in between. Regarding initial levels of behavior, both direct and indirect effects of parental knowledge were found on aggressive as well as on delinquent behavior. When the rate of change in behaviors was considered, only direct effects were found for both types of problem behavior, whereas indirect effects were absent. Gender differences were also found, with stronger effects of parenting on both aggressive and delinquent problem behavior for boys and stronger effects of peer contacts on aggressive behavior for girls. The present study shows that different behaviors of the externalizing spectrum have different trajectories and diverse relations with parenting and should not be treated as identical.
Kirsten L. BuistEmail:
  相似文献   
997.
Abstract: Anyone with a computer, scanner, and color printer has the capability for creating documents such as identification cards, passports, and counterfeit currency. Laser desorption mass spectrometry (LDMS) has been demonstrated as a powerful tool for colorant analysis. Inkjet printers are now moving largely toward the use of pigments as colorants; their insolubility makes analysis by simpler methods such as thin‐layer chromatography no longer an option. Recent developments in pigmented inkjet printer inks, such as gloss optimizers that coat pigment particles, may prohibit colorant analysis by LDMS. We demonstrate here that pigments used in inks from two Epson printers can be detected and analyzed by LDMS. Also, LDMS spectra of various colors created using a 4‐cartridge (cyan/magenta/yellow/black, CMYK) inkset are evaluated, to begin to develop an approach for unraveling LDMS data from real samples, to determine the number of inks used by a printer, and the chemical composition of the colorants.  相似文献   
998.
Abstract:  Human scent evidence is utilized as an investigative tool through canine scent discriminations based on the premise that human scent is an individualizing characteristic. This study describes the development of what is effectively a human scent barcode consisting of the relative ratios of an individual's "primary odor" compounds utilized to determine a reproducible and individualizing profile which can be stored in a searchable database for a proof of concept of human scent as a biometric measure. Triplicate hand odor samples were evaluated from 10 subjects utilizing solid phase micro-extraction gas chromatography/mass spectrometry (SPME-GC/MS) and compared via Spearman Rank Correlations. Narrowing the compounds considered for each subject to only those common in all three samples, or a subject's "primary odor constituents," produced a greater degree of both individualization and discrimination; at both correlation thresholds of 0.9 and 0.8, the individuals were correctly discriminated and identified in 99.54% of the cases.  相似文献   
999.
Minor child physical abuse has decreased in Sweden since 1979, when a law banning corporal punishment of children was passed, but more serious forms have not decreased. The aim of this study was to examine risk and background factors in cases of severe child abuse reported to the police. Files from different agencies (e.g., Social services, Adult and Child psychiatry and Pediatric clinic) for 20 children and 34 caretakers were studied. An accumulation of risk factors was found. It is concluded that when the following four factors are present, there is a risk for severe child abuse: 1) a person with a tendency to use violence in conflict situations; 2) a strong level of stress on the perpetrator and the family; 3) an insufficient social network that does not manage to protect the child; 4) a child that does not manage to protect him or herself. Thus, multiple sources of information must be used when investigating child abuse.  相似文献   
1000.
Despite nearly a century of knowledge indicating a significant number of women engaging in sexual activities with children, the phenomenon has not yet been fully acknowledged. Recently, however, there has been a marked increase in research in this area. However, due to the relatively small numbers of detections or convictions there remains a lack of data regarding: (1) the specific clinical characteristics of female sex offenders; and (2) how these clinical factors link to re-offending and treatment need. The following study examines potential risk, protective, and treatment factors that are highlighted through the process of clinical intervention, using an adapted version of the Beech and Ward (2004) risk framework. We describe how female sex offenders typically display clinical deficits in the same risk domains as their male counterparts, while noting the ways in which these deficits manifest in this population. In addition, we compare these vulnerability factors in four established types of female sex offender.  相似文献   
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