Reproductive and Developmental Risks from Ethylene Oxide: A Probabilistic Characterization of Possible Regulatory Thresholds

Ethylene oxide is a gas produced in large quantities in the United States that is used primarily as a chemical intermediate in the production of ethylene glycol, propylene glycol, non-ionic surfactants, ethanolamines, glycol ethers, and other chemicals. It has been well established that ethylene oxide can induce cancer, genetic, reproductive and developmental, and acute health effects in animals. The U.S. Environmental Protection Agency is currently developing both a cancer potency factor and a reference concentration (RfC) for ethylene oxide. This study used the rich database on the reproductive and developmental effects of ethylene oxide to develop a probabilistic characterization of possible regulatory thresholds for ethylene oxide. This analysis was based on the standard regulatory approach for noncancer risk assessment, but involved several innovative elements, such as: (1) the use of advanced statistical methods to account for correlations in developmental outcomes among littermates and allow for simultaneous control of covariates (such as litter size); (2) the application of a probabilistic approach for characterizing the uncertainty in extrapolating the animal results to humans; and (3) the use of a quantitative approach to account for the variation in heterogeneity among the human population. This article presents several classes of results, including: (1) probabilistic characterizations of ED10s for two quantal reproductive outcomes-resorption and fetal death, (2) probabilistic characterizations of one developmental outcome-the dose expected to yield a 5% reduction in fetal (or pup) weight, (3) estimates of the RfCs that would result from using these values in the standard regulatory approach for noncancer risk assessment, and (4) a probabilistic characterization of the level of ethylene oxide exposure that would be expected to yield a 1/1,000 increase in the risk of reproductive or developmental outcomes in exposed human populations.     

Forecasting mortality rates via density ratio modeling

The authors propose a semiparametric approach to modeling and forecasting age‐specific mortality in the United States. Their method is based on an extension of a class of semiparametric models to time series. It combines information from several time series and estimates the predictive distribution conditional on past data. The conditional expectation, which is the most commonly used predictor in practice, is the first moment of this distribution. The authors compare their method to that of Lee and Carter.     

Youth-Subcultural Studies: Sociological Traditions and Core Concepts

The study of youth subcultures has rich histories in the USA and UK, yet has remained a marginal subfield within cultural sociology. In this article, I begin by reviewing the significance of the Chicago school, strain theory, Birmingham school and post-subcultural studies traditions of youth-cultural and youth-subcultural research. I then conceive of a series of significant analytic concepts that over time have proven themselves to be core components of youth-subcultural studies. These analytic concepts include subcultural style, resistance, subcultural space and media, societal reaction, and identity and authenticity. In each analytic section, I explore major conceptual frames and discuss significant empirical research, on youth subcultures including punk goth, straightedge, riot grrrl skateboarding, rave and club cultures, among others.     

Which Children Will Go to Secondary School? Factors Affecting Parents' Decisions in Rural Thailand1

Abstract This study examines parents' decisions about educating some or all of their children beyond primary school in rural Thailand. Their strategies often involve choices between sons and daughters and between older versus younger children. We find that the more children there are in a family, the lower the proportion who are sent to secondary school. Parents send more sons than daughters and more youngest than eldest children. The decision is sometimes associated with a specific “investment” strategy, but it may also reflect parents' ability to afford to send children beyond primary school. Important economic factors include children's perceived earning potentials, anticipated opportunity costs, and parents' poverty status. However, the issues of access to schools and the safety of children, particularly girls, are also critically important. These concerns are often weighed as heavily, or more heavily, than economic considerations.     

Social Work Education and Clinical Learning

In response to a growing diversity of opinion regarding educational models and essential content in clinical social work education, this paper offers a perspective concerning graduate clinical curricula. Part I, the foundational piece of the paper, discusses the definition of clinical social work, social work’s core orientation and values, and influential contextual issues. The interrelated core orientations guiding knowledge and skill development are identified as the person-in-situation perspective and the concept of relationship. Based on this foundation, Part II identifies elements of a contemporary biopsychosocial knowledge base and essential clinical skills. This paper is intended to stimulate dialogue about a topic of importance to the profession and the clients it serves.     

The Age Difference Between Spouses: Variations among Developing Countries

Sub-national and cross-national variations in the age difference between spouses are investigated with data from the World Fertility Survey relating to 29 developing countries. Substantial variation within and between countries is evident. Analysis suggests that the relative age of prospective spouses is a factor taken into account in the marriage market. Observed variation in the age difference, within and between countries, cannot be explained as the simple by-product of the random matching of independently determined distributions of men's and women's ages at marriage. Certain age differences are avoided, others chosen more frequently. Preferred age differences appear to differ in the societies studied, however, and this variation can be directly interpreted in terms of two sets of factors: kinship structure and women's roles. The analysis also suggests that demographic determinants of the age difference, in particular age constraints on the pool of possible matches, are of less importance in explaining societal variations than are social structural factors.     

Playground Accessibility and Neighbourhood Social Interaction Among Parents

While the positive association between social interaction and access to green space is well accepted, little research has sought to understand the role of children??s playgrounds in facilitating social interaction within a community. Playgrounds are spaces designed to facilitate play and the interaction of children, but may also be important places of interaction between parents. In this paper we examine how access to playground spaces is related to social interaction between parents. We use two measures of accessibility (1) walking distance to the closest playground and (2) playground service area, a measure of the number of potential users of a playground based on population density. We use generalized estimating equations, an extension of generalized linear models, to control for the confounding effects of socio-economic status (income, education), neighbourhood dynamics (neighbourhood location, years in neighbourhood) and free time (daily outdoor activity, marital status, number of children) on the independent relationship between social interaction and access to playground spaces. Our results suggest that while accessibility to playgrounds is associated with social interaction among parents, the direction of the effect is opposite to existing literature on green space and social interaction; parents with low accessibility to playgrounds are more likely to interact socially with their neighbours than parents with high accessibility. Our results suggest a pattern of spatial behaviour in which the burden of poor access to some resources may actually encourage greater neighbourhood engagement. Future research studying the relationship between health and green space may benefit from studying the specific role of playground spaces.     

Knowledge, Consequences, and Experience: The Social Construction of Environmental Problems

Perhaps one of the most obvious yet difficult questions confronting sociologists concerned with large-scale environmental problems is an epistemological one: How do we know what we know about the state of the environment? This paper explores the realist and constructionist approaches to environmental-social problems and finds both inadequate as currently formulated. A case is made for a phenomenological constructionism that moves beyond relativism and simple definitional constructionism by exploring how we actually experience the world. This approach recognizes the existence of a natural world independent of our constructions, yet suggests that our knowledge of it is always mediated, indirect, and pragmatically motivated.