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11.
The objective of this article was to propose an exposure assessment model to describe the relationship between fish consumption and body methyl mercury (MeHg) levels in the Japanese population. Individual MeHg intake was estimated by the summation of species-specific fish consumption multiplied by species-specific fish MeHg levels. The distribution of fish consumed by individuals and the MeHg level in each fish species were assigned based on published data from Japanese government institutions. The probability of MeHg intake for a population was accomplished through a Monte Carlo simulation by the random sampling of fish consumption and species-specific MeHg levels. Internal body MeHg levels in blood and hair were estimated using a one-compartment model. Overall, the mean value of MeHg intake for the Japanese population was estimated to be 6.76 μg/day or 0.14 μg/kg body weight per day (bw/day), while the mean value for the hair mercury level was 2.02 μg/g. Compared with the survey data that tabulated hair mercury levels in a cross-section of the Japanese population, the simulation results matched the hair mercury survey data very well for women, but somewhat underestimated for men and all of the population. This exposure assessment model is a useful attempt at further risk assessment with respect to a risk-benefit analysis.  相似文献   
12.
Rapid growth of technology innovations promotes governments world-wide to actively explore the best way to realize its economic benefits. Likewise, Chinese government has positioned advances of high technology a driving-force to continued economic achievements, and launched various high-tech policies. This case study focuses on computer-aided design (CAD), a key field under policy support, discloses policy’s critical role. Interview/survey data from corporate and academic leaders were also collected and synthesized. The emergence of university–industry collaboration, capitalizing university intellectual property, and new modes in CAD innovation and technology diffusion are among those major findings. A Model is also proposed. The study provides new observations for debates to high-tech policy-makers and can benefit scholars and business managers seeking to understand the environment in China, and serve as a foundation for further policy and management research.  相似文献   
13.
Summary A simple mathematical model describing the species-area relation was developed. This paper dealt with the case that discrete random samples are combined. Modelling was made on the assumption that the occurrence probability of a species in a quadrat has a continuous density distribution. The model, given by the equation (6), holds only for a particular size of quadrat (i.e. the characteristic area). More general form applicable to the quadrats the size of which is near to the characteristic area was represented by the equation (9). Validity of the model was examined for the data of plant and insect communities, and it was concluded that the observation can be predicted by the model unless the size of sampling unit considerably differs from the characteristic area. The uniformity of specific density (i. e. the number of species per quadrat) and the size of characteristic area were discussed as being important in an understanding of community structure. Contributions from JIBP-CT No. 144.  相似文献   
14.
Using comparable self‐reported survey data collected among college students in the United States (n = 502) and Japan (n = 441), this study examines a paradox of higher academic deviance among otherwise more conforming Japanese youth while revisiting the debate concerning the disjuncture between aspirations and expectations/perceived outcomes in Agnew's general strain theory (GST). Confirming the paradox, our results indicate that Japanese students are significantly more deviant academically than American students. However, contrary to the expectation of GST, but in support of past empirical studies, the higher academic deviance among the Japanese, as compared to Americans, is explained by their lower aspirations, irrespective of the levels of expectations/perceived outcomes  相似文献   
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This article puts the democratic potential of using the Internet into perspective through an analysis of how collective uses of the Internet promote social capital. Research results reveal that social capital online (i.e. trust and reciprocity) is enhanced by involvement in collective use of the Internet such as participation in online communities and use of the Internet among informal groups in everyday life. This process could counter negative aspects of Internet use. Further, accumulated online social capital can be a powerful predictor of online political participation, i.e. online reciprocity has a positive effect on intention to participate in online civic discussion. Finally, the authors' analyses indicate the possibility of a spillover of online social capital into offline arenas. It is concluded that collective use of the Internet can be a lubricant for democracy.  相似文献   
17.
The Bates–Watts relative curvature measure can assess the validity of the linearized approximation in nonlinear regression models. However, it is developed based on an ordinary nonlinear regression in which the observation is assumed to be homoscedastically and normally distributed. In this article, we extend the original Bates–Watts relative curvature measure to one that can be applicable to nonlinear regression with heteroscedastic or non normal data, based on the transformation-both-sides (TBS) approach. In pharmacokinetic models, a diagnostic use of their measures is illustrated. By means of a simulation experiment, the performance of the relative curvature measure for the TBS approach is evaluated.  相似文献   
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A long tradition in stratification research argues students with higher cultural capital are likely to be treated by their teachers as possessing the “right culture,” which positively affects their academic performance. Nevertheless, the literature has paid little attention to the role of students' perception in this process. Using two waves of the China Educational Panel Survey, we investigate how students' cultural capital affects their own understanding of teacher-student interactions, including its gender difference. Fixed effects regressions show a substantially positive effect of cultural capital on the perceived frequency of teachers praising and calling on students to answer questions across subjects. Nonetheless, we also find the lack of cultural capital is not punished and that the cultural capital's effect varies across its specific components and gender. These findings pave the way for elucidating the entire causal chain of intergenerational social inequality via cultural capital, teacher bias, students’ perception, and their educational outcomes.  相似文献   
20.
Erratum     
The online version of the original article can be found at  相似文献   
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