The size of an organism reflects its metabolic rate, growth rate, mortality, and other important characteristics; therefore, the distribution of body size is a major determinant of ecosystem structure and function. Body-size distributions often are multimodal, with several peaks of abundant sizes, and previous studies suggest that this is the outcome of niche separation: species from distinct p...

The concept of change simply entails the totality of ways in which a particular entity has grown better and grown worse. Five studies suggest that this is not how people actually understand it for themselves. Rather, when asked to assess how they have "changed" over time, people bring to mind only how they have improved and neglect other trajectories (e.g., decline) that they have also experien...

Despite evidence from family studies that there is a strong genetic influence upon exceptional longevity, relatively few genetic variants have been associated with this trait. One reason could be that many genes individually have such weak effects that they cannot meet standard thresholds of genome wide significance, but as a group in specific combinations of genetic variations, they can have a...

Seven kinds of hypervariable DNA probes, which recognize hypervariable loci, were applied for individual identification of human bloodstains. Allelic frequencies and their confidence intervals among unrelated Japanese individuals were previously reported from our laboratory, and codominant segregation of the polymorphism was confirmed in family studies. One-month-old bloodstains from ten indivi...

OBJECTIVE To determine the yield and determinants of retrospective TB contact investigation in selected zones in Ethiopia. MATERIALS AND METHODS This was a community-based cross-sectional study conducted during June-October 2014.Trained lay providers performed symptom screening for close contacts of index cases with all types of TB registered for anti-TB treatment within the last three years....

This paper distills and extends recent research on the economics of human development and social mobility. It summarizes the evidence from diverse literatures on the importance of early life conditions in shaping multiple life skills and the evidence on critical and sensitive investment periods for shaping different skills. It presents economic models that rationalize the evidence and unify the...

We look at fitting regression models using data from stratified cluster samples when the strata may depend in some way on the observed responses within clusters. One important subclass of examples is that of family studies in genetic epidemiology, where the probability of selecting a family into the study depends on the incidence of disease within the family. We develop the survey-weighted esti...

This paper presents an information-boundaries perspective on the family and the Internet with the aim of helping to set the context for child development in the new media environment. Drawing from family studies, sociology, and communication, it lays out a model for viewing the family in relation to the Web. The paper draws research ideas out of the framework that center on four areas: family c...

BACKGROUND Close contacts of patients with tuberculosis (TB) have a substantial risk of developing the disease, particularly during the first year after exposure. Household contact investigation has recently been recommended as a strategy to enhance case detection in high-burden countries. However the barriers to its implementation in these settings remain poorly understood. METHODS A nested ...

Previous twin and family studies indicate that the familial aggregation of breast density is due (in part) to genetic factors. Whether these genetic influences are shared with other breast cancer risk factors, however, is not known. Using standard film-screen mammography, we screened 550 women, including 611 pairs of sisters, from the Old Order Amish population of Lancaster County, Pennsylvania...