Bielefeld University

About: Bielefeld University is a education organization based out in Bielefeld, Nordrhein-Westfalen, Germany. It is known for research contribution in the topics: Population & Quantum chromodynamics. The organization has 10123 authors who have published 26576 publications receiving 728250 citations. The organization is also known as: University of Bielefeld & UNIVERSITAET BIELEFELD.

European Pulsar Timing Array Limits on Continuous Gravitational Waves from Individual Supermassive Black Hole Binaries

Abstract: We have searched for continuous gravitational wave (CGW) signals produced by individually resolvable, circular supermassive black hole binaries (SMBHBs) in the latest European Pulsar Timing Array (EPTA) data set, which consists of ultraprecise timing data on 41-ms pulsars. We develop frequentist and Bayesian detection algorithms to search both for monochromatic and frequency-evolving systems. None of the adopted algorithms show evidence for the presence of such a CGW signal, indicating that the data are best described by pulsar and radiometer noise only. Depending on the adopted detection algorithm, the 95 per cent upper limit on the sky-averaged strain amplitude lies in the range 6 × 10−15 10^9M⊙ out to a distance of about 25 Mpc, and with Mc > 10^10M⊙ out to a distance of about 1Gpc (z ≈ 0.2). We show that state-of-the-art SMBHB population models predict <1 per cent probability of detecting a CGW with the current EPTA data set, consistent with the reported non-detection. We stress, however, that PTA limits on individual CGW have improved by almost an order of magnitude in the last five years. The continuing advances in pulsar timing data acquisition and analysis techniques will allow for strong astrophysical constraints on the population of nearby SMBHBs in the corning years.

Heterogeneous Ice Nucleation Rate Coefficient of Water Droplets Coated by a Nonadecanol Monolayer

Abstract: The heterogeneous ice nucleation rate coefficient (jhet) of water droplets coated with a monolayer of 1-nonadecanol was determined from multiple freezing/melting cycles. Freezing was monitored optically with a microscope for droplet radii between 31 and 48 μm and with a differential scanning calorimeter for radii between 320 and 1100 μm. The combination of these two techniques allows the surface area of the 1-nonadecanol nucleating agent to be varied by more than a factor of 1000, showing that jhet increases only by ∼5 orders of magnitude over a temperature range of 18 K. This is roughly 5 times less than the change in the ice nucleation rate coefficient for homogeneous ice freezing at around 238 K or for heterogeneous ice freezing in the presence of a solid ice nucleus, such as Al2O3. This temperature dependence of jhet can be reconciled with the framework of classical nucleation theory, when assuming a reduced compatibility of the alcohol monolayer with the ice embryo as the temperature decreases. We at...

Critical analysis of the current treatment guidelines for complex ptsd in adults.

Abstract: According to current treatment guidelines for Complex PTSD (cPTSD), psychotherapy for adults with cPTSD should start with a “stabilization phase.” This phase, focusing on teaching self-regulation strategies, was designed to ensure that an individual would be better able to tolerate trauma-focused treatment. The purpose of this paper is to critically evaluate the research underlying these treatment guidelines for cPTSD, and to specifically address the question as to whether a phase-based approach is needed. As reviewed in this paper, the research supporting the need for phase-based treatment for individuals with cPTSD is methodologically limited. Further, there is no rigorous research to support the views that: (1) a phase-based approach is necessary for positive treatment outcomes for adults with cPTSD, (2) front-line trauma-focused treatments have unacceptable risks or that adults with cPTSD do not respond to them, and (3) adults with cPTSD profit significantly more from trauma-focused treatments when preceded by a stabilization phase. The current treatment guidelines for cPTSD may therefore be too conservative, risking that patients are denied or delayed in receiving conventional evidence-based treatments from which they might profit.

Maintenance of binge eating through negative mood: A naturalistic comparison of binge eating disorder and bulimia nervosa

Abstract: Objective: To examine negative mood as a proximal antecedent and reinforcing condition of binge eating in binge eating disorder (BED) and bulimia nervosa (BN). Method: Using an ecological momentary assessment design, 20 women with BED, 20 women with BN, and 20 nonclinical control women were recruited from the community, provided with a portable minicomputer, and asked to rate their mood and list their thoughts at randomly-generated beep sounds and before, during, and after episodes of eating. Results: In both eating disorder groups mood before binge eating was more negative than before regular eating and at random assessment. Binge eating was followed by a deterioration of mood. The BED group revealed less antecedent negative mood than the BN group and less concomitant negative cognitions about food/eating and stress. Conclusion: Affect regulation difficulties likely lead to binge eating in both disorders, but binge eating may not be effective for regulating overall mood. © 2007 by Wiley Periodicals, Inc. Int J Eat Disord 2007.