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151.
The Texas Commission on Environmental Quality (TCEQ) has developed an inhalation unit risk factor (URF) for 1,3-butadiene based on leukemia mortality in an updated epidemiological study on styrene-butadiene rubber production workers conducted by researchers at the University of Alabama at Birmingham. Exposure estimates were updated and an exposure estimate validation study as well as dose-response modeling were conducted by these researchers. This information was not available to the U.S. Environmental Protection Agency when it prepared its health assessment of 1,3-butadiene in 2002. An extensive analysis conducted by TCEQ discusses dose-response modeling, estimating risk for the general population from occupational workers, estimating risk for potentially sensitive subpopulations, effect of occupational exposure estimation error, and use of mortality rates to predict incidence. The URF is 5.0 × 10−7 per μg/m3 or 1.1 × 10−6 per ppb and is based on a Cox regression dose-response model using restricted continuous data with age as a covariate, and a linear low-dose extrapolation default approach using the 95% lower confidence limit as the point of departure. Age-dependent adjustment factors were applied to account for possible increased susceptibility for early life exposure. The air concentration at 1 in 100,000 excess leukemia mortality, the no-significant-risk level, is 20 μg/m3 (9.1 ppb), which is slightly lower than the TCEQ chronic reference value of 33 μg/m3 (15 ppb) protective of ovarian atrophy. These values will be used to evaluate ambient air monitoring data so the general public is protected against adverse health effects from chronic exposure to 1,3-butadiene.  相似文献   
152.
How is ‘authentic’ linguistic femininity in Japan manifested in popular texts? We analyze the dialogue of female characters in Wakaba, a 2005 Japanese drama set in two very different parts of ‘regional’ Japan – Miyazaki and Kobe. Through this analysis, we examine two contradictory discourses circulated through popular media. The first is that linguistic femininity is based in Standard Japanese – a surprisingly persistent ideology despite a current trend to examine cases in which language ideology and practice do not match. Other studies reflect another dominant discourse, that of the ‘authentic’ dialect speaker, who expresses local alignment by using dialect forms outside the bounds of ideologically modern linguistic forms. The tension between acting linguistically feminine and ‘authentically’ local raises some interesting questions for Japanese language and gender studies, including studies of gendered representations: are women who are speakers of regional dialects authentically ‘feminine’? Can they be? Do some dialects express femininity better than others?  相似文献   
153.
In 2005, the National Science Foundation funded a number of projects to study the impact of Hurricane Katrina. The current article provides an overview of several research approaches used to conduct post-Katrina research. Each method had some advantages and disadvantages. The post-disaster context meant that experience from traditional survey methods often did not apply. Comparisons of advantages and disadvantages associated with each sampling method serve to inform future post-disaster research and illuminate the limits of classical research methods.  相似文献   
154.
Purpose: Many students who are lesbian, gay, bisexual, transgender, or queer (LGBTQ) face hostile school environments that can negatively impact their mental health and education. This study involved a photovoice project where high school students from a gay-straight alliance in the rural southeastern United States took photographs that depicted the issues LGBTQ students were facing and then exhibited their photographs and stories to individuals from the school system and local community to promote awareness, dialogue, and action. Methods: Twenty adults who attended the photovoice exhibit responded to an online survey about their experiences with the intervention. Results: Eighty-five percent of adults reported that the intervention made them think about issues they had not previously considered, including the struggles LGBTQ youths face, gender issues, and living in a rural community. Common emotions experienced at the intervention included feeling excited, concern for the youths, and proud of the youths. Furthermore, 81% of the adults indicated that they would take action or behave differently as a result of the intervention, including supporting and affirming LGBTQ students, using gender-neutral and -inclusive language, and confronting bias in themselves and others. Conclusions: Photovoice is a promising strategy for LGBTQ students to activate adult allies in their community.  相似文献   
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It seems difficult to find a formula in the literature that relates moments to cumulants (and vice versa) and is useful in computational work rather than in an algebraic approach. Hence I present four very simple recursive formulas that translate moments to cumulants and vice versa in the univariate and multivariate situations.  相似文献   
157.
Books received     
A Wider Perspective Needed Avraham Greenbaum (ed.), Minority Problems in Eastern Europe Between the World Wars, with Emphasis on the Jewish Minority, introduced by Edward Allworth, Hebrew University of Jerusalem, Institute of Advanced Studies. Jerusalem, 1988. pp.viii, 163.

The Jokes of Oppression David A. Harris and Izrail Rabinovich, The Jokes of Oppression: The Humour of Soviet Jews. Northvale, NJ and London: Jason Aronson, 1988. 275pp. $22.50.

A Pleasant Surprise Franti?ek Mi?eje, Revolu?nou Cestou. Spomienky na roky 1938–1948 (On the Path of Revolution: Reminiscences of the Years 1938–1948.) Bratislava: Pravda publishers on behalf of the Institute of Marxism‐Leninism of the Central Committee of the Communist Party of Slovakia, 1988. 232 pp. Illus. Bibl. Index. Kcs 19.00.  相似文献   
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Assessment of circulating CD4 count change over time in HIV-infected subjects on antiretroviral therapy (ART) is a central component of disease monitoring. The increasing number of HIV-infected subjects starting therapy and the limited capacity to support CD4 count testing within resource-limited settings have fueled interest in identifying correlates of CD4 count change such as total lymphocyte count, among others. The application of modeling techniques will be essential to this endeavor due to the typically non-linear CD4 trajectory over time and the multiple input variables necessary for capturing CD4 variability. We propose a prediction based classification approach that involves first stage modeling and subsequent classification based on clinically meaningful thresholds. This approach draws on existing analytical methods described in the receiver operating characteristic curve literature while presenting an extension for handling a continuous outcome. Application of this method to an independent test sample results in greater than 98% positive predictive value for CD4 count change. The prediction algorithm is derived based on a cohort of n = 270 HIV-1 infected individuals from the Royal Free Hospital, London who were followed for up to three years from initiation of ART. A test sample comprised of n = 72 individuals from Philadelphia and followed for a similar length of time is used for validation. Results suggest that this approach may be a useful tool for prioritizing limited laboratory resources for CD4 testing after subjects start antiretroviral therapy.  相似文献   
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