Stability of Impurities with Coulomb Potential in Graphene with Homogeneous Magnetic Field

Given a 2-dimensional no-pair Weyl operator with a point nucleus of charge Z, we show that a homogeneous magnetic field does not lower the critical charge beyond which it collapses.Comment: J. Math. Phys. (in press

Sirococcus tsugae – Causal agent of a shoot blight of Cedrus atlantica in Germany

Im Sommer 2014 wurde an mehreren Orten nahe Oldenburg/Niedersachsen ein Triebsterben an älteren Bäumen von Cedrus atlantica beobachtet, charakterisiert durch hellbraune Verfärbung von Nadeln und Nadelbüscheln mit anschließendem Absterben der betroffenen Triebe. Auf Grund spezifischer, morphologischer Merkmale sowie vergleichender DNA-Sequenzanalysen konnte als Erreger der Pilz Sirococcus tsugae ermittelt werden. Bisher war der Coelomycet nur aus Nordamerika bekannt. Die phytosanitären Fragen, die sich aus dem Vorkommen eines neuen Krankheitserregers in Deutschland ergeben, werden diskutiert. DOI: 10.5073/JfK.2015.04.02, https://doi.org/10.5073/JfK.2015.04.02In summer 2014 a shoot blight of mature trees of Cedrus atlantica was observed at several sites in private gardens and in public green spaces in the vicinity of Oldenburg, Lower Saxony. The disease is characterised by light brown discoloration of needles and fascicles, followed by dieback of the affected shoots. Based on specific morphological features as well as DNA sequence comparisons the pathogen was determined as Sirococcus tsugae. So far, this coelomycete had only been known from North America. The phytosanitary aspects resulting from the occurrence of a new tree pathogen in Germany are discussed. DOI: 10.5073/JfK.2015.04.02, https://doi.org/10.5073/JfK.2015.04.0

On the Maximal Excess Charge of the Chandrasekhar-Coulomb Hamiltonian in Two Dimensions

We show that for the straightforward quantized relativistic Coulomb Hamiltonian of a two-dimensional atom -- or the corresponding magnetic quantum dot -- the maximal number of electrons does not exceed twice the nuclear charge. It result is then generalized to the presence of external magnetic fields and atomic Hamiltonians. This is based on the positivity of |\bx| T(\bp) + T(\bp) |\bx| which -- in two dimensions -- is false for the non-relativistic case T(\bp) = \bp^2, but is proven in this paper for T(\bp) = |\bp|, i.e., the ultra-relativistic kinetic energy

Revealing Hidden Potentials of the q-Space Signal in Breast Cancer

Mammography screening for early detection of breast lesions currently suffers from high amounts of false positive findings, which result in unnecessary invasive biopsies. Diffusion-weighted MR images (DWI) can help to reduce many of these false-positive findings prior to biopsy. Current approaches estimate tissue properties by means of quantitative parameters taken from generative, biophysical models fit to the q-space encoded signal under certain assumptions regarding noise and spatial homogeneity. This process is prone to fitting instability and partial information loss due to model simplicity. We reveal unexplored potentials of the signal by integrating all data processing components into a convolutional neural network (CNN) architecture that is designed to propagate clinical target information down to the raw input images. This approach enables simultaneous and target-specific optimization of image normalization, signal exploitation, global representation learning and classification. Using a multicentric data set of 222 patients, we demonstrate that our approach significantly improves clinical decision making with respect to the current state of the art.Comment: Accepted conference paper at MICCAI 201

Antithrombotic therapy in patients with atrial fibrillation and acute coronary syndrome in the real world: Data from the Berlin AFibACS Registry

Background: Guidelines for the management of atrial fibrillation (AFib) recommend antithromboembolic treatment strategies for patients with AFib and acute coronary syndrome (AFibACS). Our study assessed how current guidelines are implemented in the metropolitan area of Berlin and which therapeutic options were chosen in light of stroke and bleeding riskin everyday practice.Methods and Results: Between April 2008 and January 2012, we included 1,295 AFibACS patients in the AFibACS Registry, as part of the Berlin Myocardial Infarction Registry. Meanage of the patients was 76 years with numerous comorbidities (15.4% former stroke, 35.0% renal failure, 43.5% diabetes, 92.8% hypertension). Of all the patients, 888 were treated with stent implantation, 91 with balloon angioplasty, and 316 conservatively. Overall mortality was 11.6%, and 8.3% in stented patients. At hospital discharge, triple therapy was administered to 49.9% of stented cases. After adjustment, odds of receiving triple therapy were lower within creasing age and renal failure. Odds were higher after stent implantation, with a higher CHA2DS2-VASc score, and with any AFib category compared to initially diagnosed AFib. Between 2008 and 2011, triple therapy increased from 33.3% to 49.8% for stented patients and did not change significantly for those treated conservatively or with balloon angioplasty.Conclusions: These data suggest that in AFibACS patients, antithrombotic treatment focused on dual antiplatelet therapy for ACS, rather than on anticoagulation therapy for stroke prevention. Factors influencing therapy at discharge were age, renal failure, stent implantation, AFib category, and CHA2DS2-VASc score. During the study period, triple therapy increased for stented patients.