Modeling Receptor-Mediated Processes with Dioxin: Implications for Pharmacokinetics and Risk Assessment

Dioxin (2,3,7,8-tetrachlorodibenzo- p -dioxin; TCDD), a widespread polychlorinated aromatic hydrocarbon, caused tumors in the liver and other sites when administered chronically to rats at doses as low as 0.01 μg/kg/day. It functions in combination with a cellular protein, the Ah receptor, to alter gene regulation, and this resulting modulation of gene expression is believed to be obligatory for both dioxin toxicity and carcinogenicity. The U.S. EPA is reevaluating its dioxin risk assessment and, as part of this process, will be developing risk assessment approaches for chemicals, such as dioxin, whose toxicity is receptor-mediated. This paper describes a receptor-mediated physiologically based pharmacokinetic (PB-PK) model for the tissue distribution and enzyme-inducing properties of dioxin and discusses the potential role of these models in a biologically motivated risk assessment. In this model, ternary interactions among the Ah receptor, dioxin, and DNA binding sites lead to enhanced production of specific hepatic proteins. The model was used to examine the tissue disposition of dioxin and the induction of both a dioxin-binding protein (presumably, cytochrome P4501A2), and cytochrome P4501A1. Tumor promotion correlated more closely with predicted induction of P4501A1 than with induction of hepatic binding proteins. Although increased induction of these proteins is not expected to be causally related to tumor formation, these physiological dosimetry and gene-induction response models will be important for biologically motivated dioxin risk assessments in determining both target tissue dose of dioxin and gene products and in examining the relationship between these gene products and the cellular events more directly involved in tumor promotion.     

In search of the wage-labour/service contract: new evidence on the validity of the Goldthorpe class schema

In this paper we examine new empirical evidence on the coherence and magnitude of the main classes in the Goldthorpe class schema. Particular attention is paid to issues that have recently been a source of academic dispute: the coherence and size of the service class and the distinction between the service class and intermediate classes. Using recently available British data collected by the Office for National Statistics we examine: (i) the extent to which measures of class-relevant job characteristics are empirically discriminated by the categories of the schema; (ii) the structure of a 'contract type' dimension of employment relations conceived of as a categorical latent variable; and (iii) the association between this latent variable and both the Goldthorpe class schema and a related measure socio-economic group (SEG). We find that the data are consistent with the existence of a three category latent 'contract type' variable largely corresponding to the notions of service, intermediate and wage-labour contracts explicit in discussions of the theoretical rationale for the Goldthorpe schema. We further find a substantial degree of fit between the latent 'contract types' and the schema. However, the service class fault line appears to lie within class I and II of the schema rather than between them and the intermediate classes which suggests a revised, smaller service class would better capture the reality of the contemporary British occupational structure.     

Learning empathy through literature

ABSTRACT

In the field of organization studies, little consideration has thus far been devoted to the study of literature. The lacuna in the extant scholarship is unfortunate insofar as there is much to be gained for researchers interested in understanding organization to critically engage with literature. As an illustrative example of how literature can inform myriad pertinent discourses in organization studies, in this piece we study the question of empathy. That is, we describe just some of what may be gleaned about empathy from literature using anecdotes from a pedagogical exercise. Finally, we close this piece with a brief overview of the articles selected for this special issue.     

Fathers' Early Emotion Talk: Associations With Income,Ethnicity, and Family Factors

Contextual, mother‐, child‐, and father‐level variables were examined in association with fathers' emotion talk to infants during a shared picture book activity, in an ethnically diverse, low‐income sample (N = 549). Significant main effects included the rate of emotion talk from fathers' romantic partners (i.e., the infant's mother), infant attention and distress, and sensitive parenting. Significant interactions were also found. Higher income African American fathers referred to negative emotions more than non‐African American higher income fathers. In addition, African American fathers who demonstrated more negative and intrusive parenting referred to positive emotions more than non‐African American fathers who demonstrated negative and intrusive parenting. Our findings support family systems theory and, specifically, the interdependence of individuals' behaviors within the family unit. Interaction effects are discussed with respect to cultural variation in beliefs about parenting behaviors and the cultural experience of African Americans, including the Black cultural experience and the minority experience.     

The Impact of Subjective Work Control, Job Strain and Work?CFamily Conflict on Fertility Intentions: a European Comparison

The link between employment and fertility is often only examined by focussing on women's labour market status or the impact of part- versus full-time employment. This study introduces a new explanation by extending research to examine how women's subjective perceptions of control or autonomy over work, job strain and work-family conflict influence fertility intentions. National-level measures of childcare enrolment under the age of three and the occurrence of part-time work are also included to examine their relation to fertility intentions and their interplay with perceptions of work. Using data from 23 countries from the 2004/5 European Social Survey (ESS), multilevel logistic regression models of fertility intentions are estimated separately for women without children and women with one child. Women with higher levels of work control are significantly more likely to intend to have a second child. Higher levels of job strain (time pressure) significantly lower fertility intentions for mothers in contexts where childcare availability is low. The prevalence of part-time work amongst the female work force significantly predicts the intention to become a mother but has different effects for women who work part-time themselves compared with full-time employees.     

Book review

Review of Ttme Senes Techniques for Economists by Terence C. Mills by Thomas B. Fomby Southern Methodst Univ.. Dept. of Economics, Dallas, TX 75275     

Who ‘dominates’ whom? Social class,conjugal households and political identification

The existence of cross-class families, where the wife's occupation is taken to be superior to that of the husband, has been seen as a challenge to conventional ways of allocating class positions to partners in the conjugal household. Data from the Social Change and Economic Life Initiative survey conducted in 1986 are used to estimate the numerical importance of such families. Three approaches to the class allocation of men and women in conjugal households are outlined: individual, conventional and dominance. The predictive validity of these approaches is then assessed with the dependent variable drawn from the domain of political party identification. The outcomes of the exercise suggest that the conventional approach may require some slight finessing with respect to female respondents in cross-class families who are active full-time in the labour market, but in the main still gives acceptable results.     

Exploring the relationship between gold and the dollar

It has often been argued that one of the reasons for holding gold is as a hedge against currency movements. An exploratory data analysis to examine the validity of this theory can be carried out quickly and simply, using some of the wide and varied range of nonparametric techniques now incorporated into statistical software—but, as Terence Mills shows, such a superficial investigation can lead to interpretations that deeper data analysis shows to be flawed.     

Proposed Legislation May Compromise Incentive to Present Unbiased Presentation of Research Data

This paper discusses some current issues and methods related to the detection of fraudulent financial reporting and draws potential implications for audit detection of fradulent scientific reporting. First, a brief history of auditor concern with fraud detection is presented. Then four issues are addressed: (1) How often does fraud occur? (2) What is fraud? (3) What are the general types of fraud? (4) How can auditors assess fraud risk and detect fraud?