Part I––Comparing Noncancer Chronic Human Health Reference Values: An Analysis of Science Policy Choices

The goal of this study was to systematically evaluate the choices made in deriving a chronic oral noncancer human health reference value (HHRV) for a given chemical by different organizations, specifically those from the U.S. Environmental Protection Agency, Health Canada, RIVM (the Netherlands), and the U.S. Agency for Toxic Substances and Disease Registry. This analysis presents a methodological approach for comparing both the HHRVs and the specific choices made in the process of deriving an HHRV across these organizations. Overall, across the 96 unique chemicals and 171 two‐way organizational comparisons, the HHRV agreed approximately 26% of the time. A qualitative method for identifying the primary factors influencing these HHRV differences was also developed, using arrays of HHRVs across organizations for the same chemical. The primary factors identified were disagreement on the critical or principal study and differential application of the total uncertainty factor across organizations. Of the cases where the total UF was the primary factor influencing HHRV disagreement, the database UF had the greatest influence.     

Part II: Quantitative Evaluation of Choices Used in Setting Noncancer Chronic Human Health Reference Values Across Organizations

Environmental and public health organizations, including the World Health Organization (WHO) and the U.S. Environmental Protection Agency (USEPA), develop human health reference values (HHRV) that set “safe” levels of exposure to noncarcinogens. Here, we systematically analyze chronic HHRVs from four organizations: USEPA, Health Canada, RIVM (the Netherlands), and the U.S. Agency for Toxic Substances and Disease Registry. This study is an extension of our earlier work and both closely examines the choices made in setting HHRVs and presents a quantitative method for identifying the primary factors influencing HHRV agreement or disagreement.⁽¹⁾ We evaluated 171 organizational comparisons, developing a quantitative method for identifying the factors to which HHRV agreement (that is, when both organizations considering the same data set the identical HHRV values) is most sensitive. To conduct this analysis, a Bayesian belief network was built using expert judgment, including the specific science policy choices analysis made in the context of setting an HHRV. Based on a sensitivity of findings analysis, HHRV agreement is most sensitive to the point of departure value, followed by the total uncertainty factor (UF), critical study, critical effect, animal model, and point of departure approach. This analysis also considered the specific impacts of individual UFs, with the database UF and the subchronic‐to‐chronic UF being identified as primary factors impacting the total UF differences observed across organizations. The sensitivity of findings analysis results were strengthened and confirmed by frequency analyses evaluating which choices most often disagreed when the HHRV and the total UF disagreed.     

Choose who’s in your circle: how women’s relationship actions during and following residential treatment help create recovery-oriented networks

ABSTRACT

Women in recovery from substance use disorders often have difficulty establishing recovery-supportive networks. This exploratory study uses qualitative thematic analysis to examine how 88 women in recovery describe the actions they take to manage their personal social networks 12 months after intake into residential substance use treatment. Participants describe disconnecting or limiting contact with recovery-endangering people and adding recovery-supportive people to their networks as primary relationship actions for maintaining recovery. Their actions to build recovery-supportive networks can provide a focus for clinical work to help them become integrated into their communities.     

Design catalogue for eco-engineering of coastal artificial structures: a multifunctional approach for stakeholders and end-users

Urban Ecosystems - Coastal urbanisation, energy extraction, food production, shipping and transportation have led to the global proliferation of artificial structures within the coastal and marine...     

The role of perceived social reality in the adoption of postmaterial values: The case of Hong Kong

While much research in the past four decades has demonstrated a turn toward postmaterial values in many developed countries in the world, there are continual debates regarding the factors behind such cultural changes. This study examines the role of certain cognitive factors in the adoption of postmaterial value orientations. Analysis of three surveys conducted between 2012 and 2016 in Hong Kong illustrate that postmaterial values are, at the individual level, tied to criticisms against social inequality and immobility. The relationship is stronger among better educated people and people with higher levels of news exposure. The analysis contributes to the broader literature on cultural change in modern societies by suggesting that social affluence is not a sufficient condition for the rise of postmaterial values. Instead, specific combinations of social conditions and a process of cognitive mobilization could initiate a postmaterial turn.     

State‐space model for proxy‐based millennial reconstruction

It is important to study historical temperature time series prior to the industrial revolution so that one can view the current global warming trend from a long‐term historical perspective. Because there are no instrumental records of such historical temperature data, climatologists have been interested in reconstructing historical temperatures using various proxy time series. In this paper, the authors examine a state‐space model approach for historical temperature reconstruction which not only makes use of the proxy data but also information on external forcings. A challenge in the implementation of this approach is the estimation of the parameters in the state‐space model. The authors developed two maximum likelihood methods for parameter estimation and studied the efficiency and asymptotic properties of the associated estimators through a combination of theoretical and numerical investigations. The Canadian Journal of Statistics 38: 488–505; 2010 © 2010 Crown in the right of Canada