GRB060218 as a Tidal Disruption of a White Dwarf by an Intermediate Mass Black Hole

A highly unusual pair of a gamma-ray burst (GRB) GRB060218 and an associated supernova SN2006aj has puzzled theorists for years. A supernova shock breakout and a jet from a newborn stellar mass compact object were put forward to explain its multiwavelength signature. We propose that the source is naturally explained by another channel, a tidal disruption of a white dwarf (WD) by an intermediate mass black hole (IMBH). The tidal disruption is accompanied by a tidal pinching, which leads to the ignition of a WD and a supernova. Some debris falls back onto the IMBH, forms a disk, which quickly amplifies the magnetic field, and launches a jet. We successfully fit soft X-ray spectrum with the Comptonized blackbody emission from a jet photosphere. The optical/UV emission is consistent with self-absorbed synchrotron from the expanding jet front. The accretion rate temporal dependence Mdot(t) in a tidal disruption provides a good fit to soft X-ray lightcurve. The IMBH mass is found to be about 10^4Msun in three independent estimates: (1) fitting tidal disruption Mdot(t) to soft X-ray lightcurve; (2) computing the jet base radius in a jet photospheric emission model; (3) inferring the central BH mass based on a host dwarf galaxy stellar mass. The supernova position is consistent with the center of the host galaxy, while low supernova ejecta mass is consistent with a WD mass. High expected rate of tidal disruptions in dwarf galaxies is consistent with one source observed by Swift satellite over several years at GRB060218 distance of 150Mpc. The encounters with the WDs provide a lot of fuel for IMBH growth.Comment: 15 pages, 5 figures, accepted to ApJ, minor change

Alterungsstudien und Studium der Betriebseigenschaften des Outer Trackers des LHCb Detektors

Der Outer Tracker ist Teil des Spurfindungssystems des LHCb-Detektors. Er benutzt Driftkammern, um die Spur eines Teilchens zu bestimmen. Die 2,5m langen Straws mit einem Durchmesser von 4,9mm werden im Proportionalmodus betrieben und sollen später die Spur mit einer Einzeltrefferauflösung von 0,2 mm bestimmen. In dieser Arbeit werden im ersten Teil die Betriebseigenschaften des Outer Trackers bestimmt. Dabei werden insbesondere Ortsauflösung und Effizienz untersucht. Der Hauptteil der Arbeit beschäftigt sich mit Alterungsstudien.Weder bei einem Test mit Röntgenstrahlen mit einer Energie von 8 keV noch mit hochionisierenden Protonen wurde eine Änderung des Modulverhaltens aufgrund von Alterungseffekten festgestellt. Die Beschleunigungsfaktoren im Vergleich zu LHCb betrugen dabei 8-180 (Anodenstrom >80 nA/cm) in den am stärksten bestrahlten Regionen. Die akkumulierte Ladung betrug bis zu 3C/cm. Bei Alterungsuntersuchungen mit Anodenströmen von weniger als 15 nA/cm (Beschleunigungsfaktor 1) wurde allerdings bei den bereits produzierten Outer Tracker Modulen schon nach wenigen Tagen (1-2 mC/cm) ein deutlicher Verlust der Gasverstärkung gemessen. Diese Alterung hängt von einer Vielzahl von Parametern wie Gasflussgeschwindigkeit oder Driftgasmischung ab und tritt nicht bei Anodenströmen >12 nA/cm auf. Die Alterung wird durch Ausgasung eines im Modul verwendeten Materials verursacht. Untersuchungen ergaben, dass die Ausgasungen wahrscheinlich durch den Epoxidkleber verursacht werden. Durch Spülen und Erwärmen der Module kann die Alterung deutlich reduziert werden, so dass nach derzeitigem Stand die Outer Tracker Module für mehrere Jahre im LHCb Detektor betrieben werden können

How can Urban Manufacturing contribute to a more sustainable energy system in cities?

The paper explores future opportunities as well as challenges arising from urban manufacturing (UM) regarding the design of sustainable energy systems for cities. Global trends affect the type of production (e.g. Industry 4.0) as well as the industrial structure (e.g. convergence of services and production) of UM in cities. This causes new requirements but also new options for the urban energy system. The study presented in this paper examines this area of tension and explores not only the potentials of waste heat use, but also additional electricity demand trough steadily advancing digitalisation. The study illustrates, that over the next few years it will be key to improve the interfaces between actors and sectors: between companies ("energy communities"), between industry and grid/energy supply company/neighbouring settlement areas and between the sectors heat-electricity-gas-mobility through e.g. power-to-x and possible uses of hydrogen. The paper concludes with a concept for integrating urban manufacturing optimally in the urban energy system for a sustainable energy transition in the future

Seasonality in extra-pulmonary tuberculosis notifications in Germany 2004-2014- a time series analysis

Background Seasonality in tuberculosis (TB) has been found in different parts of the world, showing a peak in spring/summer and a trough in autumn/winter. The evidence is less clear which factors drive seasonality. It was our aim to identify and evaluate seasonality in the notifications of TB in Germany, additionally investigating the possible variance of seasonality by disease site, sex and age group. Methods We conducted an integer-valued time series analysis using national surveillance data. We analysed the reported monthly numbers of started treatments between 2004 and 2014 for all notified TB cases and stratified by disease site, sex and age group. Results We detected seasonality in the extra-pulmonary TB cases (N = 11,219), with peaks in late spring/summer and troughs in fall/winter. For all TB notifications together (N = 51,090) and for pulmonary TB only (N = 39,714) we did not find a distinct seasonality. Additional stratified analyses did not reveal any clear differences between age groups, the sexes, or between active and passive case finding. Conclusion We found seasonality in extra-pulmonary TB only, indicating that seasonality of disease onset might be specific to the disease site. This could point towards differences in disease progression between the different clinical disease manifestations. Sex appears not to be an important driver of seasonality, whereas the role of age remains unclear as this could not be sufficiently investigated.Peer Reviewe

Quantitative MRI and loss of free ambulation in Duchenne muscular dystrophy

The purpose of this ethics approved trial was to correlate quantitative MRI with functional abilities in both ambulant and non-ambulant Duchenne muscular dystrophy (DMD). Twenty patients with genetically confirmed DMD were recruited. Physical assessment was performed using the motor function measurement (MFM) scale. Axial 3T MRI scans of the thighs were acquired using T1-weighted in- and opposed-phase images (TR=20ms, TE1=2.45ms, TE2=3.68ms, flip angle=15°) to calculate the relative fat fraction according to the two-point Dixon method in the knee extensors, flexors, and adductor muscles. The average MFM was 65.3% and correlated negatively to age (r 2=0.60). Overall mean fat fraction correlated positively to age (r 2=0.51-0.64). An average of 5% increase in mean fat fraction per year was calculated. Mean fat fraction of the quadriceps showed a high negative correlation (r 2=0.93) to the D1 (standing position and transfers) component of the MFM. A cutoff for mean fat fraction of 50% predicted loss of ambulation with a sensitivity of 100% and a specificity of 91%. Therefore, quantitative muscle MRI seems to be a promising endpoint for short clinical trials evaluating the effect of newer treatments on the time of loss of ambulation in DM

Tiny wasps, huge diversity – A review of German Pteromalidae with new generic and species records (Hymenoptera: Chalcidoidea)

Despite their ecological and economic importance, hymenopteran parasitoids are severely understudied. Even in countries with a long taxonomic history such as Germany, dating back to the 18th century and including prolific figures like Christian Gottfired Nees von Esenbeck and Otto Schmiedeknecht, those species-rich groups are seldom the subject of comprehensive research efforts, leaving their true diversity unknown. This is often due to their small size of a few millimetres on average, leading to difficulties in their identification and examination. The chalcidoid family Pteromalidae is no exception to this neglect. So far, 735 species have been reported from Germany. Estimating the diversity of this group is not possible, but it has to be assumed that many more species are still to be discovered in Germany.With this study, we improve the knowledge on pteromalid diversity and present new records of 17 genera and 41 species, previously unknown to occur in Germany. We also match and describe previously unknown sexes of two species, based on DNA barcode data. The results of this study were generated as part of the German Barcode of Life Project. The newly-recorded species are illustrated and notes on the biology and distribution are given. The ecological significance of Pteromalidae and potential value as indicators for nature conservation efforts are briefly discussed

Mergers of Supermassive Black Holes in Astrophysical Environments

Modeling the late inspiral and merger of supermassive black holes is central to understanding accretion processes and the conditions under which electromagnetic emission accompanies gravitational waves. We use fully general relativistic, hydrodynamics simulations to investigate how electromagnetic signatures correlate with black hole spins, mass ratios, and the gaseous environment in this final phase of binary evolution. In all scenarios, we find some form of characteristic electromagnetic variability whose pattern depends on the spins and binary mass ratios. Binaries in hot accretion flows exhibit a flare followed by a sudden drop in luminosity associated with the plunge and merger, as well as quasi-periodic oscillations correlated with the gravitational waves during the inspiral. Conversely, circumbinary disk systems are characterized by a low luminosity of variable emission, suggesting challenging prospects for their detection.Comment: 9 pages, 5 figures, 1 table, replaced with version accepted for publication in Ap

Muscular involvement assessed by MRI correlates to motor function measurement values in oculopharyngeal muscular dystrophy

Oculopharyngeal muscular dystrophy (OPMD) is a progressive skeletal muscle dystrophy characterized by ptosis, dysphagia, and upper and lower extremity weakness. We examined eight genetically confirmed OPMD patients to detect a MRI pattern and correlate muscle involvement, with validated clinical evaluation methods. Physical assessment was performed using the Motor Function Measurement (MFM) scale. We imaged the lower extremities on a 1.5T scanner. Fatty replacement was graded on a 4-point visual scale. We found prominent affection of the adductor and hamstring muscles in the thigh, and soleus and gastrocnemius muscles in the lower leg. The MFM assessment showed relative mild clinical impairment, mostly affecting standing and transfers, while distal motor capacity was hardly affected. We observed a high (negative) correlation between the validated clinical scores and our visual imaging scores suggesting that quantitative and more objective muscle MRI might serve as outcome measure for clinical trials in muscular dystrophie

The interplay between GPIb/IX antibodies, platelet hepatic sequestration, and TPO levels in patients with chronic ITP

Immune thrombocytopenia (ITP) is an autoimmune bleeding disorder with an incompletely understood pathophysiology but includes platelet-clearance in the spleen and liver via T cells and/or platelet autoantibodies. Strikingly, thrombopoietin (TPO) levels remain low in ITP. Platelet-glycoprotein (GP)Ibα has been described to be required for hepatic TPO generation; however, the role of GPIb antibodies in relation to platelet hepatic sequestration and TPO levels, with consideration of platelet counts, remains to be elucidated. Therefore, we examined 53 patients with chronic and nonsplenectomized ITP for whom we conducted indium-labeled autologous platelet scintigraphy and measured platelet antibodies and TPO levels. Upon stratification toward the severity of thrombocytopenia, no negative association was observed between GPIb/IX antibodies and TPO levels, suggesting that GPIb/IX antibodies do not inhibit or block TPO levels. Surprisingly, we observed a positive association between GPIb/IX antibody levels and TPO levels and GPIb/IX antibodies and platelet hepatic sequestration in patients with severe, but not mild or moderate, thrombocytopenia. In addition, platelet hepatic sequestration and TPO levels were positively associated. This collectively indicates that GPIb/IX antibodies may be associated with increased platelet hepatic sequestration and elevated TPO levels in patients with severe thrombocytopenic ITP; however, further research is warranted to elucidate the pathophysiologic mechanisms.</p