Expert Scientific Judgment and Cancer Risk Assessment: A Pilot Study of Pharmacokinetic Data

When high-dose tumor data are extrapolated to low doses, it is typically assumed that the dose of a carcinogen delivered to target cells is proportional to the dose administered to test animals, even at exposure levels below the experimental range. Since pharmacokinetic data are becoming available that in some cases question the validity of this assumption, risk assessors must decide whether to maintain the standard assumption. A pilot study of formaldehyde is reported that was undertaken to demonstrate how expert scientific judgment can help guide a controversial risk assessment where pharmacokinetic data are considered inconclusive. Eight experts on pharmacokinetic data were selected by a formal procedure, and each was interviewed personally using a structured interview protocol. The results suggest that expert scientific opinion is polarized in this case, a situation that risk assessors can respond to with a range of risk characterizations considered biologically plausible by the experts. Convergence of expert opinion is likely in this case of several specific research strategies ar executed in a competent fashion. Elicitation of expert scientific judgment is a promising vehicle for evaluating the quality of pharmacokinetic data, expressing uncertainty in risk assessment, and fashioning a research agenda that offers possible forging of scientific consensus.     

Special Educational Needs: From Disciplinary to Pedagogic Research

A review of research on special educational needs in Britain over the last two decades indicates that two concerns have been paramount. First, there has been an attempt to broaden research styles in response to the growing critique of traditional positivist research. Secondly, the problem of the perceived gap between theory and practice has been addressed. Developments have included the use of small-N studies within a positivist framework, the adoption of qualitative research strategies and the critical perspectives of sociologists. It is argued here that such developments have been largely restricted to what Michael Bassey refers to as 'disciplinary' research, neglecting the 'pedagogic' research associated with the growth of practitioner research in other areas of education. The article examines both why teacher research has been relatively neglected in special education and the kinds of contributions it might make.     

The EPA Health Risk Assessment of Methylcyclopentadienyl Manganese Tricarbonyl (MMT)

This paper describes the U.S. Environmental Protection Agency's assessment of potential health risks associated with the possible widespread use of a manganese (Mn)-based fuel additive, methylcyclopentadienyl manganese tricarbonyl (MMT). This assessment was significant in several respects and may be instructive in identifying certain methodological issues of general relevance to risk assessment. A major feature of the inhalation health risk assessment was the derivation of Mn inhalation reference concentration (RfC) estimates using various statistical approaches, including benchmark dose and Bayesian analyses. The exposure assessment component used data from the Particle Total Exposure Assessment Methodology (PTEAM) study and other sources to estimate personal exposure levels of particulate Mn attributable to the permitted use of MMT in leaded gasoline in Riverside, CA, at the time of the PTEAM study; on this basis it was then possible to predict a distribution of possible future exposure levels associated with the use of MMT in all unleaded gasoline. Qualitative as well as quantitative aspects of the risk characterization are summarized, along with inherent uncertainties due to data limitations.     

Discourse Analysis in Career Counseling and Development

Discourse analysis can be used to understand and interpret culturally and socially produced meanings regarding work and to outline how specific rules and conventions can configure meaning production of work in context. The implications of some core concepts in discourse analysis pertinent to career counseling are explored, including discourse, deconstruction, power/knowledge, psy‐complex, ideology, and identity. Such an exploration has the potential to initiate a process of critical self‐reflection in career counseling and development so as to enhance ethical, fair, and inclusive practices in the field.     

Improving OpenURL Menus: User Testing of Revisions to SFX® Menus

Twenty-one volunteers tested the usability of revisions to the Texas A&M University Libraries' SFX® OpenURL link resolver menus, including the addition of Ex Libris' new bX™ recommendation service and a plug-in which pulls additional information about the journal into the menu. The volunteers also evaluated the quality and desirability of the bX recommendations and discussed their preferences for help options and full-text format. Results of the usability testing are reported along with the resultant menu changes. This study will be of interest to librarians implementing or redesigning OpenURL menus as well as those interested in the user experience.     

Efficiency Bounds for Missing Data Models With Semiparametric Restrictions

This paper shows that the semiparametric efficiency bound for a parameter identified by an unconditional moment restriction with data missing at random (MAR) coincides with that of a particular augmented moment condition problem. The augmented system consists of the inverse probability weighted (IPW) original moment restriction and an additional conditional moment restriction which exhausts all other implications of the MAR assumption. The paper also investigates the value of additional semiparametric restrictions on the conditional expectation function (CEF) of the original moment function given always observed covariates. In the program evaluation context, for example, such restrictions are implied by semiparametric models for the potential outcome CEFs given baseline covariates. The efficiency bound associated with this model is shown to also coincide with that of a particular moment condition problem. Some implications of these results for estimation are briefly discussed.     

This Harlem life: black families and everyday life in the 1920s and 1930s

This article uses Probation Department files to reconstruct the lives of five ordinary residents of Harlem. It highlights what that black metropolis offered those outside the political and cultural elite, who have dominated historical scholarship, showing how ordinary blacks negotiated the challenges of life in northern neighborhoods, and drew on institutions and organizations, to establish and sustain new lives. We offer the kind of individualized perspective on everyday life that other scholars have provided for high culture, but which does not exist for other realms of existence in Harlem, even in early twentieth century sociological studies of black life. Where scholars seeking to distinguish the neighborhood from a slum have pointed to the prevailing pride and self-confidence of its residents, this article directs attention to more immediate, concrete supports that sustained and enriched life in Harlem. Relationships with spouses, children, siblings and cousins sustained individuals faced with the social reality of living in overcrowded, deteriorating, disease infested housing, subject to the racism of white police, politicians and employers; so too did friendships made in nightclubs, speakeasies, dances and movie theatres, and membership of churches, fraternal organizations, social clubs, and sports clubs and teams.