Cosmic rays in astrospheres

Cosmic rays passing through large astrospheres can be efficiently cooled inside these "cavities" in the interstellar medium. Moreover, the energy spectra of these energetic particles are already modulated in front of the astrospherical bow shocks. We study the cosmic ray flux in and around lambda Cephei as an example for an astrosphere. The large-scale plasma flow is modeled hydrodynamically with radiative cooling. We studied the cosmic ray flux in a stellar wind cavity using a transport model based on stochastic differential equations. The required parameters, most importantly, the elements of the diffusion tensor, are based on the heliospheric parameters. The magnetic field required for the diffusion coefficients is calculated kinematically. We discuss the transport in an astrospheric scenario with varying parameters for the transport coefficients. We show that large stellar wind cavities can act as sinks for the galactic cosmic ray flux and thus can give rise to small-scale anisotropies in the direction to the observer. Small-scale cosmic ray anisotropies can naturally be explained by the modulation of cosmic ray spectra in huge stellar wind cavities

The Relationship Between Poverty and Behavior Problems : Examining the Role of Family and Parental Factors from an Ecological Systems Perspective

The large number of children from low-income households or living in poverty are at increased risk for a range of negative outcomes, including behavior problems. The Family Stress Model is a framework that can be used to describe how poverty may shape the development of behavior problems through its influence on family processes, including parental mental health, parenting, and household environment. While the Family Stress Model has been widely replicated, studies have rarely examined the context of infancy and toddlerhood, during which family-related processes tend to be more impactful in child development. Therefore, the present study evaluated two adaptations of the Family Stress Model in a large, ethnically diverse sample of Early Head Start families (N= 2,835). Specifically, the present study investigated whether poverty, in the form of economic hardships and pressures, contributes to behavior problems in infancy and toddlerhood indirectly through its impact on four family-based risk factors (parental depression, household chaos, parenting stress, and parental sensitivity), as well as whether these factors operate independently or indirectly through parental sensitivity. Results indicated that parental depression, parenting stress, and household chaos mediated relations between economic pressure and parental sensitivity, and that parenting stress and household chaos, but not parental depression, were associated with child behavior problems indirectly through parental sensitivity. Social support was also identified as a buffer against the negative effect of economic pressure on parental depression. Implications for future Family Stress Model research with Early Head Start families, as well as for prevention and intervention approaches, are discussed

Fluorene and phenanthrene uptake by Pseudomonas putida ATCC 17514: kinetics and physiological aspects

Pseudomonas putida ATCC 17514 was used as a model strain to investigate the characteristics of bacterial growth in the presence of solid fluorene and phenanthrene. Despite the lower water-solubility of phenanthrene, P. putida degraded this polycyclic aromatic hydrocarbon (PAH) at a maximum observed rate of 1.4 ± 0.1 mg Lˉ¹ hˉ¹, higher than the apparent degradation rate of fluorene, 0.8 ± 0.07 mg Lˉ¹ hˉ¹. The role of physiological processes on the biodegradation of these PAHs was analyzed and two different uptake strategies were identified. Zeta potential measurements revealed that phenanthrene-grown cells were slightly more negatively charged (–57.5 ± 4.7 mV) than fluorene-grown cells (–51.6 ± 4.9 mV), but much more negatively charged than glucose-grown cells (–26.8 ± 3.3 mV), suggesting that the PAH substrate induced modifications on the physical properties of bacterial surfaces. Furthermore, protein-to-exopolysaccharide ratios detected during bacterial growth on phenanthrene were typical of biofilms developed under physicochemical stress conditions, caused by the presence of sparingly water-soluble chemicals as the sole carbon and energy source for growth, the maximum value for TP/EPS during growth on phenanthrene (1.9) being lower than the one obtained with fluorene (5.5). Finally, confocal laser microscopy observations using a gfp-labeled derivative strain revealed that, in the presence of phenanthrene, P. putida::gfp cells formed a biofilm on accessible crystal surfaces, whereas in the presence of fluorene the strain grew randomly between the crystal clusters. The results showed that P. putida was able to overcome the lower aqueous solubility of phenanthrene by adhering to the solid PAH throughout the production of extracellular polymeric substances, thus promoting the availability and uptake of such a hydrophobic compound.Fundação para a Ciência e a Tecnologia (FCT) – PRAXISXXI/BD/15944/98.EC Biotech program - BIO4-CT97-2015

Automatic Aorta Segmentation with Heavily Augmented, High-Resolution 3-D ResUNet: Contribution to the SEG.A Challenge

Automatic aorta segmentation from 3-D medical volumes is an important yet difficult task. Several factors make the problem challenging, e.g. the possibility of aortic dissection or the difficulty with segmenting and annotating the small branches. This work presents a contribution by the MedGIFT team to the SEG.A challenge organized during the MICCAI 2023 conference. We propose a fully automated algorithm based on deep encoder-decoder architecture. The main assumption behind our work is that data preprocessing and augmentation are much more important than the deep architecture, especially in low data regimes. Therefore, the solution is based on a variant of traditional convolutional U-Net. The proposed solution achieved a Dice score above 0.9 for all testing cases with the highest stability among all participants. The method scored 1st, 4th, and 3rd in terms of the clinical evaluation, quantitative results, and volumetric meshing quality, respectively. We freely release the source code, pretrained model, and provide access to the algorithm on the Grand-Challenge platform.Comment: MICCAI 2023 - SEG.A Challenge Contributio

Kinematics of concurrent vibratory rolling – screw system on the example of screen

The kinematics concurrent vibratory rolling screw system used in rolling screw screen that is used for sieving materials of fine and very fine grain was examined. The conducted experiments regarded the measurement of the torsional vibration sieve column (X and Y axis) and the measurement of the vertical vibration of the column (Z-axis)

Physiklehrerausbildung in Deutschland - Ergebnisse einer Umfrage

Im Jahr 2012 wurde im Rahmen einer von Ingolf Hertel und Siegfried Großmann initiierten DPG-Studie zur Lehrerausbildung eine Fragebogenerhebung zum gegenwärtigen Stand der Physiklehrerausbildung an den lehrerausbildenden Hochschulen in Deutschland durchgeführt. Gegenstand der Erhebung war neben der personellen Ausstattung vor allem die Frage der strukturellen und inhaltlichen Ausgestaltung des Studiums. Die Daten zeigen dass die Unterschiede im gymnasialen Lehramt deutlich geringer sind als im nicht-gymnasialen Lehramt, aber dennoch beachtlich sind: Der Beitrag gibt einen ersten Überblick über zentrale Ergebnisse. Eine Veröffentlichung der Gesamtauswertung ist für November 2014 vorgesehen