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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\\times 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.

We present a novel concept for a compact and robust crossed-beam optical dipole trap (cODT) based on a single lens, designed for the efficient generation of Bose-Einstein condensates (BECs) under dynamic conditions. The system employs two independent two-dimensional acousto-optical deflectors (AODs) in combination with a single high-numerical-aperture lens to provide full three-dimensional control over the trap geometry, minimizing potential misalignments and ensuring long-term operational stability. By leveraging time-averaged potentials, rapid and efficient evaporative cooling sequences toward BECs are enabled. The functionality of the cODT under microgravity conditions has been successfully demonstrated in the Einstein-Elevator in Hannover, Germany, where the beam intersection was shown to remain stable throughout the microgravity phase of the flight. In addition, the system has been implemented in the sensor head of the INTENTAS project to verify BEC generation. Additional realization of one-, two-, and three-dimensional arrays of condensates through dynamic trap shaping was achieved. This versatile approach allows for advanced quantum sensing applications in mobile and space-based environments based on all-optical BECs.

The INTENTAS project aims to develop an atomic sensor utilizing entangled Bose-Einstein condensates (BECs) in a microgravity environment. This key achievement is necessary to advance the capability for measurements that benefit from both entanglement-enhanced sensitivities and extended interrogation times. The project addresses significant challenges related to size, weight, and power management (SWaP) specific to the experimental platform at the Einstein-Elevator in Hannover. The design ensures a low-noise environment essential for the creation and detection of entanglement. Additionally, the apparatus features an innovative approach to the all-optical creation of BECs, providing a flexible system for various configurations and meeting the requirements for rapid turnaround times. Successful demonstration of this technology in the Einstein-Elevator will pave the way for a future deployment in space, where its potential applications will unlock high-precision quantum sensing.

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.

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.

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.

Two-neutrino double electron capture (2 ν ECEC) is a second-order weak-interaction process with a predicted half-life that surpasses the age of the Universe by many orders of magnitude 1 . Until now, indications of 2 ν ECEC decays have only been seen for two isotopes 2 – 5 , 78 Kr and 130 Ba, and instruments with very low background levels are needed to detect them directly with high statistical significance 6 , 7 . The 2 ν ECEC half-life is an important observable for nuclear structure models 8 – 14 and its measurement represents a meaningful step in the search for neutrinoless double electron capture—the detection of which would establish the Majorana nature of the neutrino and would give access to the absolute neutrino mass 15 – 17 . Here we report the direct observation of 2 ν ECEC in 124 Xe with the XENON1T dark-matter detector. The significance of the signal is 4.4 standard deviations and the corresponding half-life of 1.8 × 10 22  years (statistical uncertainty, 0.5 × 10 22  years; systematic uncertainty, 0.1 × 10 22  years) is the longest measured directly so far. This study demonstrates that the low background and large target mass of xenon-based dark-matter detectors make them well suited for measuring rare processes and highlights the broad physics reach of larger next-generation experiments 18 – 20 . Two-neutrino double electron capture is observed experimentally in 124 Xe with the XENON1T detector, yielding a half-life of 1.8 × 10 22 years.

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.

Background: The aim of this study was to analyze the pattern and types of sensory nerve endings in ankle ligaments using immunohistochemical techniques, in order to gain more insight into functional ankle stability. Methods: One hundred forty ligaments from 10 cadaver feet were included: the calcaneofibular and anterior/posterior talofibular ligaments from the lateral complex; inferior extensor retinaculum complex, talocalcaneal oblique and canalis tarsi ligaments from the sinus tarsi; deltoid ligament with its individual portions from the medial complex, and anterior tibiofibular ligament (ATiFL) from the syndesmosis. Mechanoreceptors were classified according to Freeman and Wyke [Acta Anat (Basel) 1967;68:321–333] after staining with hematoxylin-eosin, low-affinity neurotrophin receptor p75, protein gene product 9.5, and S-100 protein. Results: Free nerve endings were the predominant sensory endings in all four complexes, with the greatest density in the lateral and medial complexes; followed by Ruffini endings, unclassifiable corpuscles, Pacini corpuscles, and Golgi-like endings. Ruffini endings were significantly more prevalent in the ATiFL than in the medial complex, and more common than Pacini corpuscles and Golgi-like endings in the lateral, medial, and sinus tarsi complexes. A greater number of blood vessels correlated with a greater number of free nerve endings. There was a negative correlation between the number of Ruffini endings, unclassifiable corpuscles, and age. Conclusions: Free nerve endings are the dominant mechanoreceptor type in the ankle ligaments, followed by Ruffini endings. The ligaments of the lateral and medial ankle complexes are more innervated than the sinus tarsi ligaments.