Exposure Reconstruction for the TCDD-Exposed NIOSH Cohort Using a Concentration- and Age-Dependent Model of Elimination

Recent studies demonstrating a concentration dependence of elimination of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) suggest that previous estimates of exposure for occupationally exposed cohorts may have underestimated actual exposure, resulting in a potential overestimate of the carcinogenic potency of TCDD in humans based on the mortality data for these cohorts. Using a database on U.S. chemical manufacturing workers potentially exposed to TCDD compiled by the National Institute for Occupational Safety and Health (NIOSH), we evaluated the impact of using a concentration- and age-dependent elimination model (CADM) (Aylward et al., 2005) on estimates of serum lipid area under the curve (AUC) for the NIOSH cohort. These data were used previously by Steenland et al. (2001) in combination with a first-order elimination model with an 8.7-year half-life to estimate cumulative serum lipid concentration (equivalent to AUC) for these workers for use in cancer dose-response assessment. Serum lipid TCDD measurements taken in 1988 for a subset of the cohort were combined with the NIOSH job exposure matrix and work histories to estimate dose rates per unit of exposure score. We evaluated the effect of choices in regression model (regression on untransformed vs. ln-transformed data and inclusion of a nonzero regression intercept) as well as the impact of choices of elimination models and parameters on estimated AUCs for the cohort. Central estimates for dose rate parameters derived from the serum-sampled subcohort were applied with the elimination models to time-specific exposure scores for the entire cohort to generate AUC estimates for all cohort members. Use of the CADM resulted in improved model fits to the serum sampling data compared to the first-order models. Dose rates varied by a factor of 50 among different combinations of elimination model, parameter sets, and regression models. Use of a CADM results in increases of up to five-fold in AUC estimates for the more highly exposed members of the cohort compared to estimates obtained using the first-order model with 8.7-year half-life. This degree of variation in the AUC estimates for this cohort would affect substantially the cancer potency estimates derived from the mortality data from this cohort. Such variability and uncertainty in the reconstructed serum lipid AUC estimates for this cohort, depending on elimination model, parameter set, and regression model, have not been described previously and are critical components in evaluating the dose-response data from the occupationally exposed populations.     

Placement Educators’ Experiences and Perspectives of Supervising International Social Work Students in Australia

International social work students in Australia have reported difficulties in finding quality placement opportunities and dealing with issues such as language and cultural barriers. While placement issues have been mostly investigated from a student perspective, this study explores the experiences and perspectives of placement educators towards supervising international social work students. It draws on an online survey of 83 placement educators working for an Australian university. The majority of placement educators reported that they supervised international students differently to domestic students. These differences were negatively framed as challenges involving students’ language competence, their understanding of cultural norms, and knowledge of Australian welfare systems. This framing implies that cultural and linguistic differences between international students and placement educators are viewed in terms of student deficiency rather than as a positive opportunity for mutual learning and professional development.     

Unaddressed problems and research perspectives in scheduling blood collection from donors

Many optimisation problems arise in managing the Blood Donation (BD) supply chain. Most of them have been addressed in the literature, while other problems, e.g. donation scheduling, have not been sufficiently addressed so far. However, blood collection from donors may have a disruptive impact on the entire BD supply chain if not properly managed. For example, scheduling donation appointments based on some system metrics may improve the flow of blood units through the BD supply chain and increase the quality of service perceived by donors. In this short communication, we present the donation scheduling problem and highlight the lack of work in the literature that deals with this problem. Then, we analyse the impact of an unbalanced flow of blood units on the BD system and the benefits that may derive from a suitable appointment scheduling. Finally, we propose suggestions for future research in BD collection scheduling that may improve the BD process.     

Globalization and Its Countermovement: Marxian Contention or Polanyian Resistance?

This article surveys the scholarship on the countermovement against the diffusion of capitalism and market economy in the Global South. We identify two streams of analysis in the literature. On the one hand, scholars observe contentious politics instances where the spread of capitalist production relations enables the associational capacity and bargaining power of social classes. On the other hand, there are voluminous studies on contentious politics in the Global South where groups such as peasants, shopkeepers, and urban poor resist the intensification of the market economy. We use Beverly Silver's distinction between Marx‐type and Polanyi‐type protests, which focuses on how globalization makes and unmakes social groups, to unpack the heterogeneity of the impacts and experiences of globalization. We argue that although Silver's distinction is of great analytical value, there are strong warrants for separating the effects of the market economy from capitalism in studying contentious politics against globalization. Such an analytical strategy (i) expands the scope of the distinction between Marxian and Polanyian contention to social groups other than the working class and (ii) emphasizes that the roots of these struggles lie in the interconnected diffusion of capitalism and market economy.     

More than Subversion: Four Strategies for the Dominated

This article asks what strategies are available to dominated actors in fields of cultural production. Using archival and biographical materials on Ottoman/Turkish women intellectuals, we show that they effectively used, depending on their social and cultural capital and their past practices, at least four strategies. Apart from the well-theorized strategy of subversion, they could also deploy acquiescence, collaboration, and defiance. These four strategies, we argue, constitute a two-dimensional space defined by loyalty vs. resistance on one hand and the overtness vs. covertness of loyalty or resistance on the other. While much of this space is best understood in terms of reciprocal social exchange, the assumptions of exchange break down in the case of overt resistance, showing that strategy goes beyond negotiation and that the understanding of power as always-already implicated with resistance has limits.     

Coming out within transnational families: intimate confessions under Western eyes*

This article is about ‘coming out’ and the process of disclosure of queer migrants within their transnational families. Despite debates about the decreasing relevance of coming out in contemporary western societies, we argue that the process of coming out continues to be a central mode of belonging and identity construction for queers in the context of transnational migration. Interviews with migrants from Poland, Russia and Turkey in Germany on their coming out experiences show that people rely on a variety of boundaries, i.e. gender, class and ethnicity, to construct a desired way of life. Theoretically, these insights indicate the need to reframe post-structuralist theories on power, most prominently advanced by Pierre Bourdieu and Michel Foucault, from an intersectional perspective. The findings in this paper pinpoint to the challenges of transnational social life queer migrants are confronted with through empirical illustrations of perceptions of differences and ambiguities between immigration and emigration contexts. Furthermore, we advocate that sexuality is a crucial dimension of migration processes determining self-definition in relation to people and places, which makes their stories of coming out always also stories of ‘coming home’.     

New Shrinkage Parameters for the Liu-type Logistic Estimators

The binary logistic regression is a widely used statistical method when the dependent variable has two categories. In most of the situations of logistic regression, independent variables are collinear which is called the multicollinearity problem. It is known that multicollinearity affects the variance of maximum likelihood estimator (MLE) negatively. Therefore, this article introduces new shrinkage parameters for the Liu-type estimators in the Liu (2003) in the logistic regression model defined by Huang (2012) in order to decrease the variance and overcome the problem of multicollinearity. A Monte Carlo study is designed to show the goodness of the proposed estimators over MLE in the sense of mean squared error (MSE) and mean absolute error (MAE). Moreover, a real data case is given to demonstrate the advantages of the new shrinkage parameters.     

Mediation Role of Dyadic Coping on Parenting Stress and Relational Resilience in Couples

This study aims to explore the mediating role of dyadic coping between relational resilience and parenting stress on married couples. The study participants comprised 229 married couples with at least one child and who have had a major life event. The relational resilience scale, parenting stress inventory, dyadic coping scale and personal information, and life events forms were used to collect data for this study. Data were analyzed with the actor–partner interdependence mediation model. The results revealed that dyadic coping actor–partner effects did not mediate between relational resilience and parenting stress. The results were discussed in relation to the social-ecological model and relevant literature. Based on the current findings, recommendations and implications for further research and practice were also proposed.     

Economic Adversity and Voter Turnout: Evidence from Turkish Parliamentary Elections

Social Indicators Research - This paper investigates the relationship between economic adversity and voter participation in Turkish parliamentary elections. We employ a dynamic model of voter...