[Emergency service care of mountain bike elite races : Rescue concept and analysis of 5 years of world cup elite cross-country/downhill and marathon stage races]. / Rettungsdienstliche Betreuung von Mountainbike-Eliterennen : Rettungskonzept und Analyse von 5 Jahren Worldcup-Elite Cross-Country/Downhill und Marathon-Etappenrennen.

BACKGROUND: Despite the ever-gaining popularity of mountain bike sports, the number of studies in regards to injury patterns and organizational aspects of rescue services is rather sparse. To efficiently support mass events such as the Union Cycliste Internationale (UCI) World Cup and UCI Championship, the World Championships and Swiss Epic Marathon, efficient rescue concepts are crucial. Challenges include high risk of injury in disciplines such as Downhill as well as the need to cover events in remote and often rough terrain in the Swiss Alps during the Swiss Epic Marathon, providing medical services not only for participants but also for spectators. We analysed the number of injuries sustained by participants as well as the different challenges for rescue services at these events. METHODS: Retrospective analysis of emergencies at the Swiss Epic from 2016-2020, the UCI World Cup Races from 2015-2017 and 2019, as well as the UCI Championship 2018. Summary of the organizational aspects of the attending rescue services and special requirements and track concepts used at the events analysed. RESULTS: Significantly higher probability of injury in Downhill disciplines vs. Cross-Country. In particular traumatic brain injury and extremity fractures. More severe injuries (NACA III to IV) were more common in Downhill compared to other disciplines (p < 0,01). CONCLUSION: Mass events require rescue concepts tailored to the competition's sport as well as it's terrain. The number of injuries was low but their severity necessitates highly qualified personnel and efficient rescue logistics to be planned beforehand. GPS-tracking and central disposition of mobile rescue resources is essential for marathon races while track competitions benefit from a mix of stationary posts and mobile units.

[Automatic load-distributing band CPR (AutoPulse™) in prone position, feasible?] / Mechanische CPR (AutoPulse™) in Bauchlage, machbar?

BACKGROUND: Due to SARS-CoV­2 respiratory failure, prone positioning of patients with respiratory and hemodynamic instability has become a frequent intervention in intensive care units (ICUs), and even in patients undergoing transfer in an ambulance or helicopter. It has become increasingly important how to perform safe and effective CPR in prone position, achieving both an optimal outcome for the patient and optimal protection of staff from infection. MATERIALS AND METHODS: We conducted feasibility tests to assess the effects of CPR with an automatic load-distributing band (AutoPulse™) in prone position and discussed different aspects of mechanical chest compression (mCPR) in prone position. RESULTS: In supine position, AutoPulse™ generated a constant pressure depth of 3cm at a frequency of 84/min. In prone position, AutoPulse™ generated a constant pressure depth of 2.6cm at a frequency of 84/min. CONCLUSION: We found mCPR to be feasible in manikins in both prone and supine positions.

High yield of self-catalyzed GaAs nanowire growth on silicon (111) substrate templated by focused ion beam patterning.

We report and detail a lithography-free method to pattern Si substrates. In particular, a focused Ga ion beam is used to create regular patterns of holes which serve as a template for the growth of vertically aligned GaAs nanowires (NW)s on Si(111) substrates using self-catalyzed molecular beam epitaxy. We show that the hole diameter plays a crucial role in the growth of the NWs at the drilled holes. The critical parameters defining the width of the holes are: ion dose quantities, wet etching procedures, and high-temperature steps at the process of growth. As a result, we obtained a yield of more than 80% for vertically aligned NW. Compared to other methods of patterning our approach provides the following advantages: (i) it is a lithography-free procedure, (ii) allows for quick patterning process and hole diameter optimization within a small window of trial and error, (iii) and provides potential applicability for different material systems.

Spatially-resolved luminescence and crystal structure of single core-shell nanowires measured in the as-grown geometry.

We report on the direct correlation between the structural and optical properties of single, as-grown core-multi-shell GaAs/In0.15Ga0.85As/GaAs/AlAs/GaAs nanowires. Fabricated by molecular beam epitaxy on a pre-patterned Si(111) substrate, on a row of well separated nucleation sites, it was possible to access individual nanowires in the as-grown geometry. The polytype distribution along the growth axis of the nanowires was revealed by synchrotron-based nanoprobe x-ray diffraction techniques monitoring the axial 111 Bragg reflection. For the same nanowires, the spatially-resolved emission properties were obtained by cathodoluminescence hyperspectral linescans in a scanning electron microscope. Correlating both measurements, we reveal a blueshift of the shell quantum well emission energy combined with an increased emission intensity for segments exhibiting a mixed structure of alternating wurtzite and zincblende stacking compared with the pure crystal polytypes. The presence of this mixed structure was independently confirmed by cross-sectional transmission electron microscopy.

[Severe SGLT-2 inhibitor-induced euglycemic ketoacidosis-a rare but serious complication]. / Schwere euglykämische Ketoacidose unter SGLT-2-Inhibitoren ­ eine seltene, aber schwerwiegende Komplikation.

Ketoacidosis induced by sodium-glucose cotransporter­2 inhibitors (SGLT-2i) is rare. If it occurs, it is a serious clinical condition which requires immediate and correct treatment. At the moment, the occurrence of a ketoacidotic crisis necessitates permanent removal of the SGLT-2i from the patient's medication. Clear recommendations concerning the timing of discontinuation of SGLT-2i prior to planned surgical interventions are lacking. The tendency towards the undesirable effects of the medication in stressful situations is impressive. Currently, SGLT-2i are recognized as established oral antidiabetics and are becoming more popular. Clinicians should be aware of and alert to the diagnosis of ketoacidosis with normal blood glucose measurements in diabetic patients showing unspecific symptoms under administration of SGLT-2i.

[Treatment options for acute respiratory distress syndrome in neurointensive care. Individual management due to enhanced neuromonitoring? : A case report series]. / Therapieoptionen des akuten Atemnotsyndroms in der Neurointensivmedizin. Individuelles Management dank erweitertem Neuromonitoring? : Eine Fallberichtserie.

Severe pulmonary impairment can occur after traumatic brain injury or stroke. The resulting brain-lung interactions represent key points for the treatment and the subsequent outcome of the patient. Established treatment approaches, such as permissive hypercapnia and prone positioning, present the intensive care physician with divergent treatment goals in these patients with partially increased intracranial pressure. This case report series shows the instrument-based and noninstrument-based options for the treatment of acute respiratory distress syndrome (ARDS) in the simultaneous presence of intracranial pathologies. This includes equipment based therapies using extracorporeal CO2 elimination, special positioning maneuvers in specially designed hospital beds and positional maneuvers, such as prone positioning. With enhanced neuromonitoring it is possible to optimally adapt treatment measures focused on the lungs early and before secondary damage to the brain.

High-Mobility, Ultrathin Organic Semiconducting Films Realized by Surface-Mediated Crystallization.

The functionality of common organic semiconductor materials is determined by their chemical structure and crystal modification. While the former can be fine-tuned via synthesis, a priori control over the crystal structure has remained elusive. We show that the surface tension is the main driver for the plate-like crystallization of a novel small organic molecule n-type semiconductor at the liquid-air interface. This interface provides an ideal environment for the growth of millimeter-sized semiconductor platelets that are only few nanometers thick and thus highly attractive for application in transistors. On the basis of the novel high-performance perylene diimide, we show in as-grown, only 3 nm thin crystals electron mobilities of above 4 cm2/(V s) and excellent bias stress stability. We suggest that the established systematics on solvent parameters can provide the basis of a general framework for a more deterministic crystallization of other small molecules.

[Preoperative fasting period of fluids in bariatric surgery]. / Präoperative Flüssigkeitskarenz in der bariatrischen Chirurgie.

BACKROUND: Aspiration of stomach content is a severe complication during general anaesthesia. The DGAI (German Society for Anesthesiology and Intensive Care Medicine) guidelines recommend a fasting period for liquids of 2 h, with a maximum of 400 ml. Preoperative fasting can affect the patients' recovery after surgery due to insulin resistance and higher protein catabolism as a response to surgical stress. OBJECTIVES: The aim of the study was to compare a liberal fasting regimen consisting of up to 1000 ml of liquids until 2 h before surgery with the DGAI recommendation. MATERIALS AND METHODS: The prospective observational clinical study was approved by the ethics committee of the University of Leipzig. In the liberal fasting group (Glib) patients undergoing bariatric surgery were asked to drink 1000 ml of tea up to 2 h before surgery. Patients assigned to the restrictive fasting group (Gres) who were undergoing nonbariatric abdominal surgery were asked to drink no more than 400 ml of water up to 2 h preoperatively. Right after anaesthesia induction and intubation a gastric tube was placed, gastric residual volume was measured and the pH level of gastric fluid was determined. Moreover, the occurrence of aspiration was monitored. RESULTS: In all, 98 patients with a body mass index (BMI) of Glib 51.1 kg/m2 and Gres 26.5 kg/m2 were identified. The preoperative fasting period of liquids was significantly different (Glib 170 min vs. Gres 700 min, p < 0.001). There was no difference regarding the residual gastric volume (Glib 11 ml, Gres 5 ml, p = 0.355). The pH of gastric fluid was nearly similar (Glib 4.0; Gres 3.0; p = 0.864). Aspiration did not occur in any patient. CONCLUSIONS: There is evidence suggesting that a liberal fluid fasting regimen (1000 ml of fluid) in the preoperative period is safe in patients undergoing bariatric surgery.

Magnetic and structural changes in the near-surface epitaxial Y2.95La0.05Fe5O12 films after high-dose ion implantation.

The method of magnetic force microscopy was used to study the domain structure of various-thickness epitaxial Y2.95La0.05Fe5O12 iron-yttrium garnet films modified by high-dose implantation of N+ nitrogen ions. The results of multi-crystal x-ray diffractometry were analyzed, and a possible defect structure of garnets prior to and after implantation was identified. It was established that the reduction of magnetic losses observed after high-dose ion implantation is accompanied by the essential ordering of magnetic domains on the surface of implanted films. There is a direct dependence of electromagnetic properties on the dose of implanted atoms followed by a considerable sputtering and amorphization of the near-surface film layer and formation of a well-defined electromagnetic structure.

[Brown urine : Myoglobin-induced renal failure after concomitant administration of simvastatin and amiodarone]. / Brauner Urin : Myoglobininduziertes Nierenversagen nach gleichzeitiger Gabe von Simvastatin und Amiodaron.

Rhabdomyolysis is a rare but well-known complication of statin therapy. The risk is considerably increased when concomitant drugs are administered that inhibit metabolism and breakdown via the cytochrome CYP3A4. We report a case of myoglobin-induced acute renal failure secondary to the concomitant use of simvastatin and amiodarone. The risk of rhabdomyolysis is mainly determined by the statin dose; in the case of the concomitant use of CYP3A4 inhibitors, a maximal daily dose of 20 mg is recommended to avoid harmful drug interactions.

The multi-purpose hard X-ray beamline BL10 at the DELTA storage ring.

The layout and the characteristics of the hard X-ray beamline BL10 at the superconducting asymmetric wiggler at the 1.5 GeV Dortmund Electron Accelerator DELTA are described. This beamline is equipped with a Si(111) channel-cut monochromator and is dedicated to X-ray studies in the spectral range from ∼4 keV to ∼16 keV photon energy. There are two different endstations available. While X-ray absorption studies in different detection modes (transmission, fluorescence, reflectivity) can be performed on a designated table, a six-axis kappa diffractometer is installed for X-ray scattering and reflectivity experiments. Different detector set-ups are integrated into the beamline control software, i.e. gas-filled ionization chambers, different photodiodes, as well as a Pilatus 2D-detector are permanently available. The performance of the beamline is illustrated by high-quality X-ray absorption spectra from several reference compounds. First applications include temperature-dependent EXAFS experiments from liquid-nitrogen temperature in a bath cryostat up to ∼660 K by using a dedicated furnace. Besides transmission measurements, fluorescence detection for dilute sample systems as well as surface-sensitive reflection-mode experiments are presented.

Crystallization of HfO2 in InAs/HfO2 core-shell nanowires.

We report the impact of deposition parameters on the structure of HfO(2) covering InAs nanowires (NWs) being potential candidates for future field-effect transistors (FETs). Molecular beam epitaxial-grown Au-free InAs NWs were covered with HfO(2) deposited by atomic-layer deposition. The impact of the film thickness as well as the deposition temperature on the occurrence and amount of crystalline HfO(2) regions was investigated by high-resolution transmission electron microscopy (TEM) and x-ray diffraction. Compared to the deposition on planar Si substrates, the formation probability of crystalline HfO(2) on InAs NWs is significantly enhanced. Here, even 3 nm thick films deposited at 250 °C are partly crystalline. Similarly, a low deposition temperature of 125 °C does not result in completely amorphous 10 nm thick HfO(2) films, they contain monoclinic as well as orthorhombic HfO(2) nanocrystals. Combining HfO(2) and Al(2)O(3) into a laminate structure is capable of suppressing the formation of crystalline HfO2 grains.

Axial InAs/GaAs heterostructures on silicon in a nanowire geometry.

InAs segments were grown on top of GaAs islands, initially created by droplet epitaxy on silicon substrate. We systematically explored the growth-parameter space for the deposition of InAs, identifying the conditions for the selective growth on GaAs and for purely axial growth. The axial InAs segments were formed with their sidewalls rotated by 30° compared to the GaAs base islands underneath. Synchrotron X-ray diffraction experiments revealed that the InAs segments are grown relaxed on top of GaAs, with a predominantly zincblende crystal structure and stacking faults.

[Treatment of a pregnant patient after multiple trauma: rare combination with thrombotic thrombocytopenic purpura]. / Versorgung einer schwangeren Patientin nach Polytrauma: Seltene Kombination mit thrombotisch-thrombozytopenischer Purpura.

Multiple trauma during pregnancy is a relatively rare situation which poses a great challenge for the team in charge of treatment. A concomitant disease, such as thrombotic thrombocytopenic purpura (TTP) with thrombocytic coagulopathy increases the complexity of the treatment problems. This article describes the case of a 36-year-old pregnant woman referred to this hospital suffering from multiple trauma with severe liver rupture. Stabilization was achieved after an emergency Caesarean section and packing of the liver. Recurrent massive bleeding from the liver occurred after depacking and was treated successfully with recombinant factor VIIa. The concomitant TTP was treated by transfusion of fresh frozen plasma and corticosteroids. Rapid initiation of therapy was the goal to achieve hemostasis and prevent aggravation of the coagulation disorder and an unfavourable outcome despite severe thrombocytopenia.

In situ three-dimensional reciprocal-space mapping during mechanical deformation.

Mechanical deformation of a SiGe island epitaxically grown on Si(001) was studied by a specially adapted atomic force microscope and nanofocused X-ray diffraction. The deformation was monitored during in situ mechanical loading by recording three-dimensional reciprocal-space maps around a selected Bragg peak. Scanning the energy of the incident beam instead of rocking the sample allowed the safe and reliable measurement of the reciprocal-space maps without removal of the mechanical load. The crystal truncation rods originating from the island side facets rotate to steeper angles with increasing mechanical load. Simulations of the displacement field and the intensity distribution, based on the finite-element method, reveal that the change in orientation of the side facets of about 25° corresponds to an applied pressure of 2-3 GPa on the island top plane.

Strain accommodation in Ga-assisted GaAs nanowires grown on silicon (111).

We study the mechanism of lattice parameter accommodation and the structure of GaAs nanowires (NWs) grown on Si(111) substrates using the Ga-assisted growth mode in molecular beam epitaxy. These nanowires grow preferentially in the zincblende structure, but contain inclusions of wurtzite at the base. By means of grazing incidence x-ray diffraction and high-resolution transmission electron microscopy of the NW-substrate interface, we show that the lattice mismatch between the NW and the substrate is released immediately after the beginning of NW growth through the inclusion of misfit dislocations, and no pseudomorphic growth is obtained for NW diameters down to 10 nm. NWs with a diameter above 100 nm exhibit a rough interface towards the substrate, preventing complete plastic relaxation. Consequently, these NWs exhibit a residual compressive strain at their bottom. In contrast, NWs with a diameter of 50 nm and below are completely relaxed because the interface is smooth.

Energy-dispersive X-ray micro Laue diffraction on a bent gold nanowire.

This article reports on energy-dispersive micro Laue (µLaue) diffraction of an individual gold nanowire that was mechanically deformed in three-point bending geometry using an atomic force microscope. The nanowire deformation was investigated by scanning the focused polychromatic X-ray beam along the nanowire and recording µLaue diffraction patterns using an energy-sensitive pnCCD detector that permits measurement of the angular positions of the Laue spots and the energies of the diffracted X-rays simultaneously. The plastic deformation of the nanowire was shown by a bending of up to 3.0 ± 0.1°, a torsion of up to 0.3 ± 0.1° and a maximum deformation depth of 80 ± 5 nm close to the position where the mechanical load was applied. In addition, extended Laue spots in the vicinity of one of the clamping points indicated the storage of geometrically necessary dislocations with a density of 7.5 × 1013 m-2. While µLaue diffraction with a non-energy-sensitive detector only gives access to the deviatoric strain, the energy sensitivity of the employed pnCCD offers absolute strain measurements with a resolution of 1%. Here, the residual strain after complete unloading of the nanowire amounted to maximum tensile and compressive strains of the order of +1.2 and -3%, which is comparable to the actual resolution limit. The combination of white-beam µLaue diffraction using an energy-sensitive pixel detector with nano-mechanical testing opens up new possibilities for the study of mechanical behavior at the nanoscale.

Local scale structural changes of working OFET devices.

We present an in situ nanobeam grazing-incidence X-ray diffraction (nanoGIXD) study of real-sized organic field effect transistors (OFET) under applied voltage. The nano-sized beam allows for spatially resolved monitoring of the structural behavior across the poly(3-hexylthiophene) (P3HT) polymer channel and the interfacial regions of the source and drain gold electrodes before and after the operation cycle. We observe major alterations of the gold contacts, in particular diffusion of Au atoms into the polymer channel and a local reorientation of the recrystallized Au nanocrystallites quantified by Hermans' orientation factors. Therefore, the initially sharp electrode-polymer interfaces are significantly modified as a result of device operation. Our findings demonstrate that nanoGIXD has a high potential to probe functionality and reliability of working organic devices.

In situ x-ray reflectivity and grazing incidence x-ray diffraction study of L 1(0) ordering in (57)Fe/Pt multilayers.

In situ high temperature x-ray reflectivity and grazing incidence x-ray diffraction measurements in the energy dispersive mode are used to study the ordered face-centered tetragonal (fct) L 1(0) phase formation in [Fe(19 Å)/Pt(25 Å)]( × 10) multilayers prepared by ion beam sputtering. With the in situ x-ray measurements it is observed that (i) the multilayer structure first transforms to a disordered FePt and subsequently to an ordered fct L 1(0) phase, (ii) the ordered fct L 1(0) FePt peaks start to appear at 320 °C annealing, (iii) the activation energy of the interdiffusion is 0.8 eV and (iv) ordered fct FePt grains have preferential out-of-plane texture. The magneto-optical Kerr effect and conversion electron Mössbauer spectroscopies are used to study the magnetic properties of the as-deposited and 400 °C annealed multilayers. The magnetic data for the 400 °C annealed sample indicate that the magnetization is at an angle of ∼50° from the plane of the film.

Ion-induced nanopatterns on semiconductor surfaces investigated by grazing incidence x-ray scattering techniques.

In this review we cover and describe the application of grazing incidence x-ray scattering techniques to study and characterize nanopattern formation on semiconductor surfaces by ion beam erosion under various conditions. It is demonstrated that x-rays under grazing incidence are especially well suited to characterize (sub)surface structures on the nanoscale with high spatial and statistical accuracy. The corresponding theory and data evaluation is described in the distorted wave Born approximation. Both ex situ and in situ studies are presented, performed with the use of a specially designed sputtering chamber which allows us to follow the temporal evolution of the nanostructure formation. Corresponding results show a general stabilization of the ordering wavelength and the extension of the ordering as a function of the ion energy and fluence as predicted by theory. The in situ measurements are especially suited to study the early stages of pattern formation, which in some cases reveal a transition from dot to ripple formation. For the case of medium energy ions crystalline ripples are formed buried under a semi-amorphous thick layer with a ripple structure at the surface being conformal with the crystalline/amorphous interface. Here, the x-ray techniques are especially advantageous since they are non-destructive and bulk-sensitive by their very nature. In addition, the GI x-ray techniques described in this review are a unique tool to study the evolving strain, a topic which remains to be explored both experimentally and theoretically.