The standard interpretation of direct-detection limits on dark matter involves particular assumptions of the underlying WIMP-nucleus interaction, such as, in the simplest case, the choice of a Helm ...form factor that phenomenologically describes an isoscalar spin-independent interaction. In general, the interaction of dark matter with the target nuclei may well proceed via different mechanisms, which would lead to a different shape of the corresponding nuclear structure factors as a function of the momentum transfer q. We study to what extent different WIMP-nucleus responses can be differentiated based on the q-dependence of their structure factors (or “form factors”). We assume an overall strength of the interaction consistent with present spin-independent limits and consider an exposure corresponding to XENON1T-like, XENONnT-like, and DARWIN-like direct detection experiments. We find that, as long as the interaction strength does not lie too much below current limits, the DARWIN settings allow a conclusive discrimination of many different response functions based on their q-dependence, with immediate consequences for elucidating the nature of dark matter.
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Experiments based on noble elements such as gaseous or liquid argon or xenon utilize the ionization and scintillation properties of the target materials to detect radiation-induced recoils. A ...requirement for high light and charge yields is to reduce electronegative impurities well below the ppb (parts per billion, 1 ppb
=
1
×
10
-
9
mol/mol) level. To achieve this, the target material is continuously circulated in the gas phase through a purifier and returned to the detector. Additionally, the low backgrounds necessary dictate low-Rn-emanation rates from all components that contact the gas. Since commercial pumps often introduce electronegative impurities from lubricants on internal components or through small air leaks, and are not designed to meet the radiopurity requirements, custom-built pumps are an advantageous alternative. A new pump has been developed in Muenster in cooperation with the nEXO group at Stanford University and the nEXO/XENON group at Rensselaer Polytechnic Institute based on a magnetically-coupled piston in a hermetically sealed low-Rn-emanating vessel. This pump delivers high performance for noble gases, reaching more than 210 standard liters per minute (slpm) with argon and more than 170 slpm with xenon while maintaining a compression of up to 1.9 bar, demonstrating its capability for noble gas detectors and other applications requiring high standards of gas purity.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract Acute aortic dissection is a life-threatening disease with a high rate of mortality. At the Institute of Legal Medicine of the Hanover Medical School, 30 cases with aortic dissections were ...found during autopsy and examined histologically between 2006 and 2009. The grade of medial alterations in the form of cystic medial necrosis, elastin fragmentation, fibrosis and medionecrosis were estimated semi-quantitatively. In order to assess the normal aging process, samples of the aortic wall of 25 decedents without dissecting aneurysms were analyzed histologically. This study demonstrates that there are partly quantitative differences, particularly with a statistically significant increase in cystic medial necrosis ( p < 0.001) and elastin fragmentation ( p < 0.001), between aortas from dissecting aneurysms and the normal aging aorta, which may help to identify genetically predisposed relatives of patients with a dissection of the aorta.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Abstract Procalcitonin is regarded as a valuable marker for sepsis in living persons and even in post-mortem investigations. At the Institute of Legal Medicine, 25 autopsy cases with suspected ...bacterial infectious diseases or sepsis were examined using the semi-quantitative PCT-Q® -test (B.R.A.H.M.S., Germany) in 2010 and 2011. As controls, 75 cadavers were used for which there was no suspicion of a bacterial infectious disease or sepsis. Femoral blood was cultured from the cases and from controls, and samples from the brain, heart, lungs, liver, spleen and kidneys were examined histologically for findings seen in sepsis. Twelve cases in the sepsis/infectious disease group (48%) were classifiable as sepsis following synopsis of PCT levels, autopsy results, and histopathological and microbiological findings. This study shows that the semi-quantitative PCT-Q® -test is a useful supplementary marker in routine autopsy investigations, capable of classifying death as due to sepsis.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The XENON collaboration aims for the direct detection of cold dark matter in form of weakly interacting massive particles (WIMPs). A dual phase time projection chamber filled with liquid xenon is ...used to detect the WIMP-nucleon interaction. For the next generation experiment XENON1T with an active target mass of 1 ton of xenon, a new distillation column to remove krypton out of xenon to a concentration of < 5 × 10−13 (0.5 ppt) natural krypton in xenon is designed and tested at the Institut für Kernphysik, Universitat Munster. The experimental setup together with two diagnostic tools is presented, as well as one stability test of a 11 hour distillation run at the designed flowrate of 3 kg per hour.
The course of GFAP expression by astrocytes has been immunohistochemically investigated during the first 30 weeks after human brain injury. In order to provide reliable data for a forensic wound age ...estimation, a quantitative morphometric analysis was performed considering the different topographic regions of the cortex as well as of the white matter. Compared to the GFAP immunoreactivity in unaltered control tissue, significantly increased numbers of GFAP positive astroglial cells could be detected adjacent to the cortical contusion from 1 day up to 4 weeks after brain injury.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, PRFLJ, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
8.
Petechial bleedings in sudden infant death Fracasso, Tony; Vennemann, Mechtild; Klöcker, Mirjam ...
International journal of legal medicine,
03/2011, Volume:
125, Issue:
2
Journal Article
Peer reviewed
The autopsy reports of 484 cases of deceased infants (201 females, 283 males) were analysed retrospectively for the existence of external and internal petechial bleedings (PET). The cases were ...divided into five groups on the basis of the cause of death (sudden infant death syndrome, sepsis, airway infections, asphyxia and trauma). Internal PET (pleural, pericardial, epicardial, thymic and peritoneal) were observed in each group with a lower prevalence in cases of trauma. The highest prevalence of external (cutaneous and conjunctival) PET was detected in cases of asphyxia (38% and 31%, respectively). However, even if with low prevalence, such bleedings were detected in every group. Factors like sex, age, cardiopulmonary resuscitation and its duration did not influence the presence of PET. The detection of external PET at autopsy is a suspicious finding that suggests asphyxia. Because of the possible natural origin of these bleedings, the medicolegal investigation has to be as complete as possible and has to include histology as mandatory.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, PRFLJ, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The XENON1T experiment searches for dark matter particles through their scattering off xenon atoms in a 2 metric ton liquid xenon target. The detector is a dual-phase time projection chamber, which ...measures simultaneously the scintillation and ionization signals produced by interactions in target volume, to reconstruct energy and position, as well as the type of the interaction. The background rate in the central volume of XENON1T detector is the lowest achieved so far with a liquid xenon-based direct detection experiment. In this work we describe the response model of the detector, the background and signal models, and the statistical inference procedures used in the dark matter searches with a 1 metric ton×year exposure of XENON1T data, that leads to the best limit to date on WIMP-nucleon spin-independent elastic scatter cross section for WIMP masses above 6 GeV/c2.
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The XENON1T experiment at the Laboratori Nazionali del Gran Sasso is the most sensitive direct detection experiment for dark matter in the form of weakly interacting particles (WIMPs) with masses ...above 6 GeV/c2 scattering off nuclei. The detector employs a dual-phase time projection chamber with 2.0 metric tons of liquid xenon in the target. A one metric ton×year exposure of science data was collected between October 2016 and February 2018. This article reports on the performance of the detector during this period and describes details of the data analysis that led to the most stringent exclusion limits on various WIMP-nucleon interaction models to date. In particular, signal reconstruction, event selection, and calibration of the detector response to nuclear and electronic recoils in XENON1T are discussed.
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