Environmental Tobacco Smoke: Exposure-Response Relationships in Epidemiologic Studies

Demonstration of a dose-response relationship for environmental tobacco smoke (ETS) is an important indication of causality. Central to the analysis and interpretation of dose-response relations as described in epidemiological studies is the relationship between dose and exposure. It must be recognized that in studies of ETS we have only surrogate measures of dose, and these surrogate measures (based on exposure) are imperfect. The question-based measures of ETS exposure generally have not been standardized, may have limited validity and reliability, and cannot comprehensively describe total ETS exposure, exposure to individual ETS components, nor doses of biologically relevant agents at target sites. Nevertheless, useful data have been yielded in epidemiologic studies linking ETS exposure to increased respiratory infection and symptoms, reduced lung growth in children, and increased lung cancer in nonsmoking adults. The more consistent exposure-response data for studies on acute health in children may reflect the greater difficulty in measuring exposure in studies of chronic health in adults.     

On the Complexity of Constructing Evolutionary Trees

In this paper we study a few important tree optimization problems with applications to computational biology. These problems ask for trees that are consistent with an as large part of the given data as possible. We show that the maximum homeomorphic agreement subtree problem cannot be approximated within a factor of , where N is the input size, for any 0 in polynomial time unless P = NP, even if all the given trees are of height 2. On the other hand, we present an O(N log N)-time heuristic for the restriction of this problem to instances with O(1) trees of height O(1) yielding solutions within a constant factor of the optimum. We prove that the maximum inferred consensus tree problem is NP-complete, and provide a simple, fast heuristic for it yielding solutions within one third of the optimum. We also present a more specialized polynomial-time heuristic for the maximum inferred local consensus tree problem.     

A blueprint for career change when you don't know what you want to do

Follow the paths of a gynecologist turned investment banker and an internist who became a medical writer. Both used a proven process to change their careers and determine what they wanted to do.     

Facilitators and barriers to employment: the perspectives of people with psychiatric disabilities and employment service providers

This study examined the perspectives of people with psychiatric disabilities and employment service providers regarding factors that most directly help or hinder consumer efforts to obtain and maintain employment. Forty-four adults with serious mental illness (SMI) (consumers) and 30 providers participated in 12 focus groups across Massachusetts. We began both consumer and provider groups by posing two broad questions: 1) what factors most help people with SMI get and keep jobs (facilitators), and 2) what factors most prevent people with SMI from getting and keeping jobs (barriers)? Data were analyzed qualitatively and both person and environmental factors were highlighted. Among facilitators, participants agreed that quality consumer-provider relationships and individualized employment services are most instrumental in helping consumers achieve employment goals. Participants identified a range of environmental barriers, including issues related to the service system, entitlement programs, non-human resources, and social stigma. Implications for services are discussed.     

A Canadian experience with an intervention programme for vulnerable families: lessons for German social work and policy

Schools are an important community resource that can foster social connections and enhance the health and wellbeing of children and families in Germany through information, health promotion and interventions. While developing social connections between the school and vulnerable families—those who are most limited in their access to other sources of information, education and intervention—is complex and challenging, it is nonetheless critical. This paper reports on the role of Families and Schools Together (F&ST), a school-based intervention aimed at vulnerable families, in building and promoting the social connections, or social capital, that strengthen families and communities. Thematic analysis of semi-structured interviews revealed that programme participants perceived an increase in their social capital in all three of its dimensions (bonding, bridging and linking). The paper highlights the importance of social capital in building stronger, more resilient families and of strengthening relations between parents and schools, and contributes to the sharing of experience and views on matters concerning families in Germany.     

Assessing multiple prior models of behaviour under ambiguity

The recent spate of theoretical models of behaviour under ambiguity can be partitioned into two sets: those involving multiple priors and those not involving multiple priors. This paper provides an experimental investigation into the first set. Using an appropriate experimental interface we examine the fitted and predictive power of the various theories. We first estimate subject-by-subject, and then estimate and predict using a mixture model over the contending theories. The individual estimates suggest that 24% of our 149 subjects have behaviour consistent with Expected Utility, 56% with the Smooth Model, 11% with Rank Dependent Expected Utility and 9% with the Alpha Model; these figures are close to the mixing proportions obtained from the mixture estimates where the respective posterior probabilities of each of them being of the various types are 25%, 50%, 20% and 5%; and using the predictions 22%, 53%, 22% and 3%. The Smooth model appears the best.     

Italian Children's Understanding of War: A Domain-Specific Approach

Studies of children's conceptions of war, which have been carried out up to now mainly by asking for a definition of war and associating it with other notions, have found few age-related changes after the age of 6. Considering the complexity of the concept, and its embeddedness in the political conceptual domain, which emerges at around 11 years, we expect that greater differences should emerge if children's ideas on the causes and consequences of war, and the actors involved, are carefully assessed. Semi-structured interviews carried out with a total of 80 Italian children from 2nd to 8th grades confirmed this hypothesis. Many 2nd graders described war as a clash between collectives without structure, attributing all decisions about starting, the development of, and ending a war to the individual fighters and explaining these decisions (when they did) as due to emotions such as hatred, envy, revenge, or being tired or unwilling to fight any longer. Most 6th and 8th graders depicted war as a clash between nation-states, attributing decisions about its starting and ending to political authorities on the basis of political and economic reasons, and the actual fighting of battles to an organized army collaborating with, or subordinate to, political authorities. Many 2nd and 4th graders also showed a mixed pattern of answers, involving both political authorities and individual fighters, thus showing that the transition from the rudimentary backward conception to the more advanced one occurs through the piecemeal addition and deletion of concepts and beliefs.