The galaxy cluster ZwCl 2341.1+0000 is a merging system at z = 0.27, which hosts two radio relics and a central, faint, filamentary radio structure. The two radio relics have unusually flat ...integrated spectral indices of −0.49 ± 0.18 and −0.76 ± 0.17, values that cannot be easily reconciled with the theory of standard diffusive shock acceleration of thermal particles at weak merger shocks. We present imaging results from XMM–Newton and Chandra observations of the cluster, aimed to detect and characterize density discontinuities in the intracluster medium. As expected, we detect a density discontinuity near each of the radio relics. However, if these discontinuities are the shock fronts that fuelled the radio emission, then their Mach numbers are surprisingly low, both ≤2. We studied the aperture of the density discontinuities, and found that while the NW discontinuity spans the whole length of the NW radio relic, the arc spanned by the SE discontinuity is shorter than the arc spanned by the SE relic. This startling result is in apparent contradiction with our current understanding of the origin of radio relics. Deeper X-ray data are required to confirm our results and to determine the nature of the density discontinuities.
A core-collapse supernova will emit a neutrino burst that can be detected on Earth. If the neutrinos travel through the Earth before reaching the detector they oscillate via interaction with Earth's ...matter, yielding oscillations in the neutrino energy spectrum. The frequency of these oscillations in energy is correlated with the pathlength traveled in the Earth and therefore contains information on the supernova location. For this technique to be useful for pointing, good energy resolution, well-known oscillation parameters and high statistics are required. This method is inferior to pointing with elastic scattering in a water Cherenkov detector but could be applied for scintillator-type detectors which have better energy resolution but weak intrinsic pointing capabilities. By the time a nearby supernova happens the requirements might well be fulfilled, and if no water Cherenkov detector is running at that time it may provide the only possibility to gain directional information. The pointing quality can be further improved by the combination of measurements from multiple detectors and also by taking relative timing into account.
The study was conducted to analyse possible interactions between noise and shift work on fatigue as a function of age. In a large questionnaire survey, we assessed personal and environmental risk ...factors related to fatigue. Noise exposure at work (L
A
eq
,
8hr
) was measured with personal noise dosimetry. The sample included 254 day and shift workers, and was divided into 2 age groups (<40- and >40-year-olds). Noise exposure had a main effect on fatigue. The highest noise exposure resulted in an increase in the fatigue level of older shift workers. The quantity of sleep mainly depended on the type of shift and age. Our data suggest that the most important factor generating fatigue could be related to industrial noise exposure, a factor which seems to aggravate work-related fatigue generated in a synergic manner by shift work and ageing. Senior workers should be prevented from cumulating those occupational stressors.
The galaxy cluster ZwCl 2341.1+0000 is a merging system at z=0.27, which hosts two radio relics and a central, faint, filamentary radio structure. The two radio relics have unusually flat integrated ...spectral indices of -0.49 +/- 0.18 and -0.76 +/- 0.17, values that cannot be easily reconciled with the theory of standard diffusive shock acceleration of thermal particles at weak merger shocks. We present imaging results from XMM-Newton and Chandra observations of the cluster, aimed to detect and characterise density discontinuities in the ICM. As expected, we detect a density discontinuity near each of the radio relics. However, if these discontinuities are the shock fronts that fuelled the radio emission, then their Mach numbers are surprisingly low, both <=2. We studied the aperture of the density discontinuities, and found that while the NW discontinuity spans the whole length of the NW radio relic, the arc spanned by the SE discontinuity is shorter than the arc spanned by the SE relic. This startling result is in apparent contradiction with our current understanding of the origin of radio relics. Deeper X-ray data are required to confirm our results and to determine the nature of the density discontinuities.
A cross-sectional study was carried out in 1985 among 5941 hospital workers from the Regional and University Hospital Center (CHRU) of Strasbourg on the occasion of the occupational medical ...examinations. The purpose was to determine the importance of low back pain among hospital staff and to describe the relationship between individual and occupational characteristics and the onset of these symptoms. Our results confirm the risk-factors determined by other investigators: age, sex, length of service, heavy work assignments (nursing aides, stretcherbearers, nurses, etc.) but also underline the role of obesity and previous attacks of low back pain, and invalidate the part musculoskeletal abnormalities play in this pathology.
Focused femtosecond laser pulses are used to create scattering damage in the core of polymer optical fibers (POF). The resulting structures are investigated regarding morphology by light microscopy ...and backscattered intensity using optical time domain reflectometry (OTDR). Quasi-distributed optical fiber sensing is proposed by evaluating backscatter changes at the inscribed scatter centers. Application examples for quasi-distributed measurement of fiber bends and temperature are demonstrated.
A microring resonator sensor device for sensitive detection of the explosive 1,3,5-trinitrotoluene (TNT) is presented. It is based on the combination of a silicon microring resonator and tailored ...receptor molecules.
Disorder of sexual development (DSD) is a rare condition. The surgical treatment of these patients includes investigation of the internal genitalia, evaluation of the gonads, and if necessary ...gonadectomy. The prevention of germ cell tumors is the most important issue in the surgical treatment of this varied and special group of patients. This study aimed to evaluate the role of laparoscopy in the surgical treatment of patients with DSD.
Over a 4-year-period, all patients presenting with DSD who underwent laparoscopic surgery at our institution were retrospectively reviewed. Operative procedure, age at the time of surgery, and histopathological results were evaluated. In addition, karyotypes and phenotypes were investigated.
Altogether, 12 patients undergoing 14 laparoscopic procedures were included. Median age at the time of surgery was 6 years with a range from 9 months to 17 years. Explorative laparoscopy was performed in all patients. In seven children, laparoscopic gonadectomy was necessary. Histopathologic examination revealed germ cell tumors in four children. In two patients, a gonadoblastoma was identified; in two patients, a dysgerminoma was found. Inguinal exploration was performed in four patients and led to removal of gonadal remnants in one case and gonadopexy in three cases. In two patients presenting with repeated urinary tract infections, laparoscopic removal of an utriculus was performed.
Laparoscopic gonadal biopsy, gonadopexy, and gonadectomy can be performed successfully, even in patients with germ cell tumors. To define guidelines for the surgical treatment of patients with DSD, further prospective and multicenter studies are necessary.
Abstract Purpose The aim of this study was to clarify the incidence of postoperative complications in infants undergoing laparoscopic hernia repair within the first six months of life. Methods ...Retrospective, single-institution study comparing term and preterm babies undergoing surgery between March 2005 and September 2012. The charts were reviewed for postoperative complications and pre-existing diseases. Results In the term group 188 of 199 babies (94.5%) had an uneventful postoperative course. Eleven patients (5.5%) presented postoperative complications, three of them (1.5%) developed severe respiratory complications. A relation between pre-existing diseases and postoperative complications could be identified in two patients. Laparoscopy possibly induced cardiorespiratory instability in one infant. In the preterm group 109 of 137 babies (79.6%) had an uneventful postoperative course. 28 preterm infants (20.4%) developed postoperative complications, seven of them (5.1%) presented severe respiratory complications. Pre-existing diseases were identified as an influencing factor in 22 preterm infants. In one patient laparoscopy possibly caused minor instability of a pre-existing cardiac anomaly. Conclusions Postoperative complications are low in both groups, although the incidence is increased in preterm infants. Pre-existing diseases are a major influencing factor for preterm infants. In very few infants laparoscopy may have induced instability of cardiac anomalies.
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