Free University of Berlin

About: Free University of Berlin is a education organization based out in Berlin, Germany. It is known for research contribution in the topics: Population & Context (language use). The organization has 35195 authors who have published 66525 publications receiving 2094403 citations. The organization is also known as: FU Berlin.

Maturation of active zone assembly by Drosophila Bruchpilot

Abstract: Synaptic vesicles fuse at active zone (AZ) membranes where Ca2+ channels are clustered and that are typically decorated by electron-dense projections. Recently, mutants of the Drosophila melanogaster ERC/CAST family protein Bruchpilot (BRP) were shown to lack dense projections (T-bars) and to suffer from Ca2+ channel–clustering defects. In this study, we used high resolution light microscopy, electron microscopy, and intravital imaging to analyze the function of BRP in AZ assembly. Consistent with truncated BRP variants forming shortened T-bars, we identify BRP as a direct T-bar component at the AZ center with its N terminus closer to the AZ membrane than its C terminus. In contrast, Drosophila Liprin-α, another AZ-organizing protein, precedes BRP during the assembly of newly forming AZs by several hours and surrounds the AZ center in few discrete punctae. BRP seems responsible for effectively clustering Ca2+ channels beneath the T-bar density late in a protracted AZ formation process, potentially through a direct molecular interaction with intracellular Ca2+ channel domains.

Planning and Self-Efficacy in the Adoption and Maintenance of Breast Self-Examination: A Longitudinal Study on Self-Regulatory Cognitions

Abstract: Many women may be reluctant to perform breast self-examination (B.S.E.) regularly due to motivational or self-regulatory deficits. The Health Action Process Approach (Schwarzer, R. (1992). Self-efficacy in the adoption and maintenance of health behaviors: theoretical approaches and a new model. In: Schwarzer, R. (Ed.), Self-efficacy: Thought Control of Action , pp. 217-243. Hemisphere, Washington DC; Schwarzer, R. (2001). Social-cognitive factors in changing health-related behavior. Current Directions in Psychological Science , 10 , 47-51.), a health behavior change model that advocates the separation of motivation and action phases, such as goal setting and goal pursuit, was applied to data from 418 young women whose risk perceptions, outcome expectancies, self-efficacy, intention to perform B.S.E., planning, and reported examination behaviors were examined at two points in time. Risk perception was found to have a negligible influence in a path analysis, whereas self-efficacy emerged as the best predict...

Boltzmann generators: Sampling equilibrium states of many-body systems with deep learning

Abstract: Computing equilibrium states in condensed-matter many-body systems, such as solvated proteins, is a long-standing challenge. Lacking methods for generating statistically independent equilibrium samples in "one shot," vast computational effort is invested for simulating these systems in small steps, e.g., using molecular dynamics. Combining deep learning and statistical mechanics, we developed Boltzmann generators, which are shown to generate unbiased one-shot equilibrium samples of representative condensed-matter systems and proteins. Boltzmann generators use neural networks to learn a coordinate transformation of the complex configurational equilibrium distribution to a distribution that can be easily sampled. Accurate computation of free-energy differences and discovery of new configurations are demonstrated, providing a statistical mechanics tool that can avoid rare events during sampling without prior knowledge of reaction coordinates.

Magnesium deficiency and hypertension: correlation between magnesium-deficient diets and microcirculatory changes in situ

Abstract: Rats maintained for 12 weeks on diets moderately or more severely deficient in magnesium showed significant elevations in arterial blood pressure compared to control animals. Examination of the mesenteric microcirculation in situ revealed that dietary magnesium deficiency resulted in reduced capillary, postcapillary, and venular blood flow concomitant with reduced terminal arteriolar, precapillary sphincter, and venular lumen sizes. The greater the degree of dietary magnesium deficiency the greater the reductions in microvascular lumen sizes. These findings may provide a rationale for the etiology, as well as treatment, of some forms of hypertensive vascular disease.