Geometrical interpretation of fluctuating hydrodynamics in diffusive systems

We discuss geometric formulations of hydrodynamic limits in diffusive systems. Specifically, we describe a geometrical construction in the space of density profiles --- the Wasserstein geometry --- which allows the deterministic hydrodynamic evolution of the systems to be related to steepest descent of the free energy, and show how this formulation can be related to most probable paths of mesoscopic dissipative systems. The geometric viewpoint is also linked to fluctuating hydrodynamics of these systems via a saddle point argument.Comment: 19 page

ConReg: Analysis and Visualization of Conserved Regulatory Networks in Eukaryotes

Transcription factors (TFs) play a fundamental role in cellular regulation by binding to promoter regions of target genes (TGs) in order to control their gene expression. TF-TG networks are widely used as representations of regulatory mechanisms, e.g. for modeling the cellular response to input signals and perturbations. As the experimental identification of regulatory interactions is time consuming and expensive, one tries to use knowledge from related species when studying an organism of interest. Here, we present ConReg, an interactive web application to store regulatory relations for various species and to investigate their level of conservation in related species. Currently, ConReg contains data for eight model organisms. The regulatory relations stored in publicly available databases cover only a small fraction both of the actual interactions and also of the regulatory relations described in the scientific literature. Therefore, we included regulatory relations extracted from PubMed and PubMedCentral using sophisticated text-mining approaches and from binding site predictions into ConReg. We applied ConReg for the investigation of conserved regulatory motifs in D. melanogaster. From the 471 regulatory relations in REDfly our system was able to identify 66 confirmed conserved regulations in at least one vertebrate model organism (H. sapiens, M. musculus, R. norvegicus, D. rerio). The conserved network consists among others of the well studied motifs for eye-development and the pan-bilaterian kernel for heart specification, which are well-known examples for conserved regulatory relations between different organisms. ConReg is available at http://services.bio.ifi.lmu.de/ConReg/ and can be used to analyze and visualize regulatory networks and their conservation among eight model organisms. It also provides direct links to annotations including literature references to potentially conserved regulatory relations

Twice Chosen: Spouse Matching and Earnings Among Women in First and Second Marriages

This study examines spousal matching for females in second-order marriages. It is based on detailed data from longitudinal Swedish population data registers. We aim to follow women who marry, divorce, and subsequently remarry compared with females who marry and stay married over the course of the study interval. The earnings of both groups are modeled through regression analysis in the year prior to their marriages along with the earnings of each husband. The residuals from the regressions represent unobservables in the process of earnings generation. From the regressions we obtain spouse-to-be pairs of earnings residuals and we measure the correlation of residuals for each marital regime. Overall, we find significant positive correlations for all three of the marital partitions. The correlation tends to be smaller for the first of a sequence of marriages for women who divorce than for women who marry and stay so. For the second of the successive marriages, however, the correlation of the residuals is larger than that for women who marry but once. We also find evidence of “matching” between successive husbands. Women who marry men with unmeasured positive earnings capacities, in the event of divorce, tend to select and match in a similar fashion the second time around.Marital matching; Remarriage; Assortative mating; Earnings