Capillary Condensation and Interface Structure of a Model Colloid-Polymer Mixture in a Porous Medium

We consider the Asakura-Oosawa model of hard sphere colloids and ideal polymers in contact with a porous matrix modeled by immobilized configurations of hard spheres. For this ternary mixture a fundamental measure density functional theory is employed, where the matrix particles are quenched and the colloids and polymers are annealed, i.e. allowed to equilibrate. We study capillary condensation of the mixture in a tiny sample of matrix as well as demixing and the fluid-fluid interface inside a bulk matrix. Density profiles normal to the interface and surface tensions are calculated and compared to the case without matrix. Two kinds of matrices are considered: (i) colloid-sized matrix particles at low packing fractions and (ii) large matrix particles at high packing fractions. These two cases show fundamentally different behavior and should both be experimentally realizable. Furthermore, we argue that capillary condensation of a colloidal suspension could be experimentally accessible. We find that in case (ii), even at high packing fractions, the main effect of the matrix is to exclude volume and, to high accuracy, the results can be mapped onto those of the same system without matrix via a simple rescaling.Comment: 12 pages, 9 figures, submitted to PR

Culture and Co-Morbidity in East and West Berliners

Following the collapse of socialism, fluctuations in cardiac mortality rates in East Germany and a West-to-East cardiac health gradient became topics of interest. Researchers suggested possible causes for these phenomena, including stress from postsocialism. I proposed that a cultural investigation of heart disease comorbid with depression could inform our understanding of the potential health effects of the postsocialist transition. I conducted ethnographic and survey research. In the study described here, I administered a depression scale (CES-D) and an ethnographically derived measure of cultural stress (Good Life Survey) to over 200 East and West Berliners with cardiovascular disease. Comparison of the groups’ depression means revealed no difference. However, correlation of the Good Life Survey and the CES-D revealed unique profiles of cultural variables associated with depression in the two groups, suggesting that culture shapes depression and cardiac risk. I discuss the value of cultural studies to comorbidity research

The Romanian Grassland Database (RGD): historical background, current status and future perspectives

This report describes the Romanian Grassland Database (RGD), registered under EU-RO-008 in the Global Index of Vegetation-Plot Databases (GIVD). This collaborative initiative aims at collecting all available vegetation-plot data (relevés) of grasslands and other open habitats from the territory of Romania and providing them for science, nationally and internationally, e.g. via the European Vegetation Archive (EVA) and the global database “sPlot”. It mainly contains data from wet, mesic, dry, saline, alpine and rocky grasslands, but also some other vegetation types like heathlands, mires, ruderal, segetal, aquatic and cryptogam-dominated vegetation. The currently 21,685 relevés have mainly been digitised from literature sources (90%), while the rest comes from individual unpublished sources (10%). We report on the background and history of RGD, explain its “Data Property and Governance Rules” under which data are contributed and retrieved and outline how RGD can contribute to research in the fields of vegetation ecology, macroecology and conservation