Suppose independent observations Xi , i = 1, . . . , n are observed from a mixture model f (x;Q) ≡ ∫ f (x; ) dQ( ), where is a scalar and Q( ) is a nondegenerate distribution with an unspecified form. We consider to estimate Q( ) by nonparametric maximum likelihood (NPML) method under two scenarios: (1) the likelihood is penalized by a functional g(Q); and (2) Q is under a constraint g(Q) = g0....

Exposure to stressful events can be differently perceived by individuals and can have persistent sequelae depending on the level of stress resilience or vulnerability of each person. The neural processes that underlie such clinically and socially important differences reside in the anatomical, functional, and molecular connectivity of the brain. Recent work has provided novel insight into some ...

BACKGROUND The origins of mental disorders arise often in childhood. Early life is a period of unique sensitivity with long lasting effects on mental health. However, the mechanisms for these effects remain unclear. OBJECTIVE This thesis describes a variety of studies using a developmental framework to promote greater understanding of the influence of nature (genotypes) and nurture (e.g., env...

Human exposure to excessively warm weather, especially in cities, is an increasingly important public health problem. This study examined heat-related health inequalities within one city in order to understand the relationships between the microclimates of urban neighborhoods, population characteristics, thermal environments that regulate microclimates, and the resources people possess to cope ...

OBJECTIVE Posttraumatic stress disorder (PTSD) is associated with high rates of psychiatric comorbidity. Existing theories consider comorbidity as a consequence of PTSD (model 1), PTSD and comorbidity as a consequence of shared factors of vulnerability (model 2), and comorbidity as a consequence of trauma-type specific mechanisms (model 3). METHOD To compare the explanatory value of these mod...

Life events, perceived social support, and psychological symptoms were studied prospectively among older adolescents during the transition from high school to college. These variables were reciprocally related to one another in patterns which changed over a period of 6 months. The findings are supportive of a transactional model of stress that emphasizes reciprocal, rather than linear, paths of...

A gene-environment (GxE) interaction is implicated in both the pathophysiology and treatment of major depressive disorder (MDD). This study modeled the effects of genetic vulnerability by using the Flinders sensitive line (FSL), a rat model of depression and its control counterpart-the Flinders resistant line (FRL). The effects of environmental vulnerability (e.g., early-life stress) were model...

The immediate aftermath of Katrina focused the world's attention on the vulnerability of the urban poor and racial/ethnic minority groups in New Orleans. This vulnerability can be viewed in terms of site, the proximity of a neighborhood to a hazard, and situation, the social context of that neighborhood. Vulnerabilities, associated with demographic characteristics such as being poor, being a me...