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991.
Russell Pittman 《Economic Change and Restructuring》2007,40(3):207-221
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.
相似文献
Russell PittmanEmail: |
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.
相似文献
Stefan Lutz (Corresponding author)Email: |
993.
Ailsa Henderson Steven D. Brown S. Mark Pancer Kimberly Ellis-Hale 《Journal of youth and adolescence》2007,36(7):849-860
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.
相似文献
Kimberly Ellis-HaleEmail: |
994.
Gender Differences in the Educational Expectations of Urban,Low-Income African American Youth: The Role of Parents and the School 总被引:2,自引:1,他引:1
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.
相似文献
Dana WoodEmail: |
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.
相似文献
Jeffrey T. Cookston (Corresponding author)Email: |
996.
Ellen Reitz Peter Prinzie Maja Deković Kirsten L. Buist 《Journal of youth and adolescence》2007,36(5):623-634
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.
相似文献
Kirsten L. BuistEmail: |
997.
Shawn Donnelly Josette E. Marrero Trevor Cornell Kevin Fowler John Allison Ph.D. 《Journal of forensic sciences》2010,55(1):129-135
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.
Allison M. Curran Ph.D. ; Paola A. Prada B.S. ; Kenneth G. Furton Ph.D. 《Journal of forensic sciences》2010,55(1):50-57
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.
Eva -Maria Annerbäck Carl -Göran Svedin Per A. Gustafsson 《Journal of family violence》2010,25(2):165-172
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.
Ian A. Elliott Hilary J. Eldridge Sherry Ashfield Anthony R. Beech 《Journal of family violence》2010,25(6):595-602
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