Estimating the transmission probability of human immunodeficiency virus in injecting drug users in Thailand

We estimate the transmission probability for the human immunodeficiency virus from seroconversion data of a cohort of injecting drug users (IDUs) in Thailand. The transmission probability model developed accounts for interval censoring and incorporates each IDU's reported frequency of needle sharing and injecting acts. Using maximum likelihood methods, the per needle sharing act transmission probability estimate between infectious and susceptible IDUs is 0.008. The effects of covariates, disease dynamics, mismeasured exposure information and the uncertainty of the disease prevalence on the transmission probability estimate are considered.     

Chains and networks,territories and scales: towards a relational framework for analysing the global economy

A vast and continually expanding literature on economic globalization continues to generate a miasma of conflicting viewpoints and alternative discourses. This article argues that any understanding of the global economy must be sensitive to four considerations: (a) conceptual categories and labels carry with them the discursive power to shape material processes; (b) multiple scales of analysis must be incorporated in recognition of the contemporary ‘relativization of scale’; (c) no single institutional or organizational locus of analysis should be privileged; and (d) extrapolations from specific case studies and instances must be treated with caution, but this should not preclude the option of discussing the global economy, and power relations within it, as a structural whole. This paper advocates a network methodology as a potential framework to incorporate these concerns. Such a methodology requires us to identify actors in networks, their ongoing relations and the structural outcomes of these relations. Networks thus become the foundational unit of analysis for our understanding of the global economy, rather than individuals, firms or nation states. In presenting this argument we critically examine two examples of network methodology that have been used to provide frameworks for analysing the global economy: global commodity chains and actor‐network theory. We suggest that while they fall short of fulfilling the promise of a network methodology in some respects, they do provide indications of the utility of such a methodology as a basis for understanding the global economy.     

Relations Between Women's Depressive Symptoms and Perceptions of Infant Distress Signals Varying in Pitch

Fifteen nondepressed, 15 moderately depressed, and 15 severely depressed women rated tape‐recordings of a newborn infant's hunger cry digitally altered to increase in fundamental frequency in 100 Hz increments. Cries were rated on 4 perceptual (e.g., arousing‐not arousing) and 6 caregiving rating scale items (e.g., cuddle, feed) used in previous studies (Zeskind, 1983). Analyses of variance showed that, as cry pitch increased, cries were rated as more arousing, aversive, urgent, and sick sounding. Highest pitched cries received highest levels of caregiving interventions. Severely depressed women rated cries as less perceptually salient and less likely to elicit active caregiving responses. Interaction effects showed that severely depressed women were least responsive to highest pitched cries. These results suggest that women's depression may alter perceptions of infant distress signals, especially at times of greater infant distress.     

Creating Stable Racially and Ethnically Diverse Communities in the United States: A Model for the Future

We examine fourteen stable, racially and ethnically diverse communities in nine US cities to understand what produces such communities. These communities in the context of the US experience of increased, multiracial, and multiethnic diversity in the early twenty-first century can serve as a policy model as both the US and European nations look ahead toward more diverse societies. After providing a brief history of US segregation patterns, we provide an analysis of factors related to stable diversity. We found two types of diversity. Diversity-by-direction communities, which are more likely to be black:white communities, consciously worked to preserve diversity through an array of community-based efforts. Diverse-by-circumstance communities, which are more likely to be multiracial, multiethnic communities with significant immigrant populations, have been faced with an unplanned diversity, which they are now working to preserve. Among the characteristics of stable diverse communities are the presence of: social seams linking different groups, community organizations involved in preserving diversity, public discussion of values of what produces 'good' community, and distinctive physical or environmental characteristics that continue to attract new residents.     

Aftermath of tragic events: the development and use of community support meetings on a university campus

Colleges and universities need to be prepared to address the psychological impact of tragedies on their campuses. In this article, the author describes the development and successful implementation of campus postvention services in the aftermath of college student deaths by suicide as well as by natural and accidental causes. The program has been well received and has gone a long way toward helping the campus community come together and heal after these types of tragedies. College officials adapted the program to address issues related to troubling national and international events as well local incidents, such as suicide attempts and students' loss of housing through fires. The author provides specific instructions so that readers can replicate the program on their own campuses, and additional materials are available upon request.     

The Perceptions of Infant Distress Signals Varying in Pitch by Cocaine‐Using Mothers

Perceptual responses to infant distress signals were studied in 16 cocaine‐using and 15 comparison mothers. All mothers rated tape recordings of 48 replications of a newborn infant's hunger cry digitally altered to increase in fundamental frequency in 100‐Hz increments. Cries were rated on 4 perceptual (arousing, aversive, urgent, and sick) and 6 caregiving rating scale items (clean, cuddle, feed, give pacifier, pick up, and wait and see) used in previous studies. Analyses of variance showed that, as cry pitch increased, cries were rated as more arousing, aversive, and urgent sounding. The highest pitched cries received the highest ratings for caregiving interventions. Main effects for cocaine use showed cocaine‐using mothers (a) rated cries as less arousing, aversive, urgent, and sick; (b) indicated they were less likely to pick up or feed the infant; and (c) indicated they more likely to give the crying infant a pacifier or just “wait and see.” A Group x Cry Pitch interaction effect showed that mothers in the cocaine group gave higher ratings to wait and see as the pitch of the cries increased, whereas mothers in the comparison group gave lower ratings to wait and see as the pitch of the cries increased. These ratings indicate that cocaine‐using mothers found cries to be less perceptually salient and less likely to elicit nurturant caregiving responses. These results suggest that maternal cocaine use is associated with altered perceptions of infant distress signals that may provide the basis for differential social responsivity in the caregiving context.     

Toward Cost-Benefit Analysis of Acute Behavioral Effects of Toluene in Humans

There is increasing interest in being able to express the consequences of exposure to potentially toxic compounds in monetary terms in order to evaluate potential cost-benefit relationships of controlling exposure. Behavioral effects of acute toluene exposure could be subjected to cost-benefit analysis if the effects of toluene were quantitatively compared to those of ethanol ingestion, which has been monetized for applied contexts. Behavioral effects of toluene and ethanol were quantified by meta-analysis of studies from the peer-reviewed literature describing their effects on choice reaction time (reaction time in a test requiring a subject to choose among two or more alternatives before responding). The internal doses of these compounds were estimated by a general physiological and toxicokinetic (GPAT) simulation from exposure parameters provided in the reports. The reported effects were converted to a common metric (proportion of baseline) and related to the estimated internal doses of toluene and ethanol, from which dose-effect equations were fitted. The estimated effect of toluene was compared to the estimated effect of ethanol on the same dependent variable by deriving a dose-equivalence equation (DEE) to express the dose of toluene as an equivalent dose of ethanol on the basis of equal effect magnitude. A nomogram was constructed by GPAT simulation to relate the environmental exposure concentration of toluene to the equivalent effect magnitude of a range of ethanol internal doses. Behavioral effects and their evaluation are determined by internal doses, which in turn are determined by a variety of variables. In addition to concentration and duration of exposure, which determine internal dose by pharmacokinetic processes, the activity level of exposed persons is a major factor. This analysis provides a continuous function of the consequences of toluene exposure expressed as ethanol-equivalent doses within confidence limits. The resulting function has the potential to estimate the monetary values of behavioral deficits caused by a range of exposures to toluene from existing monetized information on ethanol.