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31.
Carsten A. Holz 《当代中国》2002,11(32):515-538
China's industrial state-owned enterprises (SOEs) have seen a secular decline in profitability throughout the reform period. Barry Naughton argues that this decline was in large part due to a decline in monopoly rents as competition with enterprises in other ownership forms increased. Fan Gang and Woo Wing-Thye, on the other hand, contend that profitability declined across all sectors independent of the degree of competition, and that excessive labor remuneration accounts for the broad decline in SOE profitability. Testing the two hypotheses with aggregate sectoral and provincial data from the mid-1980s to the late-1990s, neither appears convincing. Yet at closer inspection these are not competing hypotheses. The two causes affect overall profitability through different channels. Competition and labor remuneration have a highly significant impact on intermediate profitability measures that take the two channels into account separately. Together they explain most of the variation in overall profitability.  相似文献   
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Hjelmeland H  Grøholt B 《危机》2005,26(2):64-72
Research has shown that the prevalence of deliberate self-harm (DSH) is higher in adolescents than in adults, but little is known about other differences. In this study we compare adolescent and adult DSH-patients regarding factors contributing to the suicidal act. In two regions in Norway, 98 persons under 20 years of age and 83 older persons were interviewed following an act of DSH. They were compared regarding intentions involved in the DSH, precipitating circumstances, level of suicidal intent, medical seriousness of the act, depression, hopelessness, and self-esteem. Few differences were found. The adults more often wanted to escape from unbearable thoughts or situations, or to receive care and attention. Adults also reported a slightly higher level of medical seriousness of the DSH act, more psychiatric problems, and substance abuse. The similarities between young and adult DSH-patients are striking. The differences found are most likely related to factors of age itself, such as cognitive immaturity, impulsivity, and lack of experience in enduring problems.  相似文献   
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The human teeth are a valuable source of information concerning identification and age calculation in forensic sciences. Dental treatment often causes permanent alteration of the teeth, which is visible on radiographs. The correlation of prosthetic restorations, root canal fillings and periodontal bone loss with chronological age has not yet been used for determining the completed 18th year of life in teenagers and young adults, e. g. for legal and anthropological purposes. The aim of this study was to determine whether the evaluation of such findings on radiographs correlates with the chronological age in teenagers and young adults. MATERIAL AND METHODS: The dental X-rays (orthopantomogram, OPG) of 1053 outpatients (age: 14 to 24 years) were avaluated. The values "prosthetically restored", "filled dental root", or "periodontal bone loss" were recorded for each tooth present. The data were then evaluated using statistical tools. RESULTS: The correlation between the number of prosthetically restored teeth and the chronological age is high. The positive predictive value of determining an age of at least 18 years proved to be very high. However, these findings are rarely present in this age group. The number of endodontically treated teeth correlated less exactly with age. On the other hand, the determination of periodontal bone loss gave reasonable positive predictive values for the threshold value "chronological age of 18 years or more". DISCUSSION: This study provides for the first time predictive values for the estimation whether a person is 18 years of age, based on the evaluation of teeth with prosthetic restorations, root canal fillings or periodontal bone loss on OPGs only. Whereas the number of patients with such findings is generally low in this age group, some of the positive findings can be used for age estimation as an adjunct to other sources of age calculation. The sole application of these criteria is not recommended, as sanitary conditions of the teeth depend on both social and individual circumstances. Therefore, the calculated values also reflect the culture of the sample studied. Finally, they are time-dependent and have to be compared to data from other populations. These results have some bearing on the field of forensic odontology.  相似文献   
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Degradation of human DNA extracted from forensic stains is, in most cases, the result of a natural process due to the exposure of the stain samples to the environment. Experiences with degraded DNA from casework samples show that every sample may exhibit different properties in this respect, and that it is difficult to systematically assess the performance of routinely used typing systems for the analysis of degraded DNA samples. Using a batch of artificially degraded DNA with an average fragment size of approx. 200 bp a collaborative exercise was carried out among 38 forensic laboratories from 17 European countries. The results were assessed according to correct allele detection, peak height and balance as well as the occurrence of artefacts. A number of common problems were identified based on these results such as strong peak imbalance in heterozygous genotypes for the larger short tandem repeat (STR) fragments after increased PCR cycle numbers, artefact signals and allelic drop-out. Based on the observations, strategies are discussed to overcome these problems. The strategies include careful balancing of the amount of template DNA and the PCR cycle numbers, the reaction volume and the amount of Taq polymerase. Furthermore, a careful evaluation of the results of the fragment analysis and of automated allele calling is necessary to identify the correct alleles and avoid artefacts.  相似文献   
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Nineteen Y-chromosomal short tandem repeats (STRs), DYS19, DYS389-I, DYS389-II, DYS390, DYS391, DYS392, DYS393, DYS385, DYS388, DYS434, DYS435, DYS436, DYS437, DYS438, DYS439, DYS460, DYS461 and DYS462 were typed in Inuit (n=70) and Danish (n=62) population samples.  相似文献   
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Initially Norwegian climate policy was very ambitious and Norway stood forth as a pusher on the international scene. Over time Norwegian policy has become more sober, stressing the need for differentiated commitments and flexible implementation. In contrast to the initial enthusiastic phase, climate change policy has been increasingly seen in pragmatic economic terms. Still, Norway is no laggard, as it has shown more willingness to pay for abatement measures than many other countries.  相似文献   
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The policy network literature has provided important insight into the way in which public policy is made in Western societies. Most network studies have focused on processes within networks and have paid little attention to the conceptualization of policy outcomes and the theoretical link between network type and policy type. This article defines and categorizes environmental policy and suggests a proposition on the link between network types and environmental policy types. It is argued that the existence of tight and closed policy communities in sectors subject to environmental regulation is associated with the introduction of low cost environmental policies. In contrast, open and loose issue networks are associated with high cost environmental policies.  相似文献   
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