Predictors of Obesity in Adults: The Roles of Demographic Factors, Body Dissatisfaction, Depression, and Life Stress

This study explored the link between sociodemographic and psychological factors when predicting obesity. Analyses were conducted on an Internet sample of 1664 male and female participants from the Teachers College Columbia University Eating and Self Image Survey. Independent variables included sociodemographic factors such as race, sex, geographic location, and socioeconomic status (SES) and psychological variables such as body image dissatisfaction (BID), depression, and life stress. The dependent variable for all analyses was obesity. An initial two-step hierarchical logistic regression was fitted to the data with sex, geographic location, race, and education (a proxy for income) in the first step and BID, depression, and life stress in the second step. All sociodemographic variables were found to be significant in the first step with obesity being predicted by having a high school education or less, being Black, residing in a southern state, and being female. However, after entering the psychological variables in the second step, being Black was the only sociodemographic variable to retain significance with high BID, being depressed, and higher amounts of life predicting obesity. A second series of hierarchical logistic regressions were performed separately to assess to what extent race, gender, and education combined with the effects of BID, depression, and life stress moderate obesity. There was no evidence that the product of race and any of the psychological factors moderated obesity. However, it was revealed that the combination of gender by BID was a significant moderator of obesity (but not the effects of depression and life stress) with females with elevated levels of BID being more likely to report being obese. The product of education by BID moderated obesity with the combination of a college education or beyond and elevated amounts of BID predicting obesity. The product of education by life stress also moderated the effects of obesity, with individuals with a high school education or less and who reported higher amounts of life stress showing increased likelihood of being obese. The product of depression and SES did not prove to be a significant moderator of obesity. On the whole, this study provides insight into the interactions of sociodemographic and psychological variables as predictors of obesity in adults

Interconnectivity of habitats in soil:combining X-ray micro tomography and thin sectioning to reveal fungal-soil structure interactions

The extreme heterogeneity and interconnectivity of the 3-dimensional pore space within soil makes it a unique habitat for the diverse microbial population and has a pivotal role in microbial interactions. Manipulation and quantification of the 3-dimensional pore space and the spatial distribution of micro-organisms is therefore essential if we are to fully understand microbial interactions. Here we pack soil microcosms at different bulk-densities to manipulate soil structure and use x-ray micro tomography and soil thin sections to analyse the effect on the connectivity of the pore volume and on fungal exploration