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Interlocking Particle Structures (IPS) are geometrically stable assemblies, usually fabricated from plate type elements that are interconnected by slotted joints. IPS are demountable and their components have the potential to be used and reused in different structures and configurations. This paper explores the applicability of birch plywood panels, which are characterized by a high surface hardness, for this type of structural system. Experimental tests were conducted to determine the mechanical properties of birch plywood plates. Moreover, IPS connections with different geometrical properties were investigated for two different load exposures: bending and rotation. The characteristics under bending exposure are influenced by the orientation of the face-veneers. For the rotational load exposure, very small strength and stiffness properties have been identified. A linear elastic finite element model is presented that shows a wide agreement with the test results. The study serves as an initial probe into the performance of IPS structures at the component level. Various aspects that are relevant for the design of IPS, such as the assembly, the accuracy and challenges regarding digital fabrication, the durability, and the structural performance are discussed.

This dissertation presents methods for guaranteeing safety of autonomous vehicles. To cope with the unknown future evolution of prior unseen traffic situations that are usually only partially observable, we develop novel solutions for predicting detected and hidden traffic participants and for planning collision-free maneuvers in a fail-safe manner. Our methods can serve as a safety layer for existing planning frameworks and can drastically reduce the number of traffic accidents. Diese Dissertation präsentiert neuartige Methoden, um die Sicherheit von autonomen Fahrzeugen zu garantieren. Dafür müssen zuvor unbekannte und nur teilweise einsehbare Verkehrsszenarien bewältigt werden, deren zukünftiger zeitlicher Verlauf sehr ungewiss ist. Die entwickelten Lösungen prädizieren sowohl erfasste als auch verdeckte Verkehrsteilnehmer und planen kollisionsfreie Manöver für das eigene Fahrzeug in einer ausfallsicheren Art und Weise. Für bestehende Systeme können diese Methoden als Sicherheitsebene eingesetzt werden, wodurch die Häufigkeit von Verkehrsunfällen drastisch reduziert wird.

Background: Conditions during blood product storage and transportation should maintain quality. The aim of this in vitro study was to investigate the effect of interruption of agitation, temporary cooling (TC), and pneumatic tube system transportation (PTST) on the aggregation ability (AA) and mitochondrial function (MF) of platelet concentrates (PC). Study Design and Methods: A PC was divided equally into four subunits and then allocated to four test groups. The control group (I) was stored as recommended (continuous agitation, 22 ± 2°C) for 4 days. The test groups were stored without agitation (II), stored as recommended, albeit 4°C for 60 minutes on day (d)2 (III) and PTST (IV). Aggregometry was measured using Multiplate (RocheAG; ADPtest, ASPItest, TRAPtest, COLtest) and MF using Oxygraph‐2k (Oroboros Instruments). The basal and maximum mitochondrial respiratory rate (MMRR) were determined. AA and MF were measured daily in I and II and AA in III and IV on d2 after TC/PTST. Statistical analysis was performed using tests for matched observations. Results: Eleven PCs were used. TRAP‐6 induced AA was significantly lower in II when compared to I on d4 (P = 0.015*). In III the ASPItest was significantly lower (P = 0.032*). IV showed no significant differences. The basal and MMRR were significantly reduced over 4 days in I and II (for both rates in both groups: P =

IntroductionThe history of the use of telemedicine in maritime medicine dates back to the 1930s. In the early 2000s, the German Navy built up a telemedicine network which today is installed in all ships and provides a connection to the medical infrastructure ashore. The objective of this study was to optimize the implementation of telemedicine based on the experience gained in the German Navy. For this purpose, qualitative and quantitative methods were used to identify determinants which affect the use of telemedicine in order to determine whether there is any need for optimization.MethodsThe study was conducted using a mixed methods design. First, guideline-based interviews were conducted with Navy medical officers who had been recruited via various email distribution lists. The interviews were then transcribed and coded. In an analysis, deductive and inductive categories were derived from the codes. Hypotheses were deduced from the interviews, too, and used to develop a questionnaire.Besides the medical officers, other Navy medical personnel with experience in the field of telemedicine took part in the survey. The study was concluded by a descriptive analysis of the quantitative data.ResultsThe analysis of the interviews revealed that a regular use of telemedicine workstations increased the users’ confidence and, in their opinion, improved medical treatment. Technical and organizational problems posed obstacles, which increased the use of partly insecure alternatives. A proper technical support was regarded as a precondition for effectively using telemedicine.The results of the quantitative analysis showed that consultation was mainly sought for dermatological (46%), surgical (24%), and internal (22%) conditions.ConclusionThe study revealed determinants for the use of telemedicine in the German Navy. Factors improving the motivation of the users should be strengthened in order to optimize the use of telemedicine. Furthermore, it can be assumed that a successful implementation will be supported by reducing or eliminating obstacles. The findings on the main reasons for seeking medical advice could be taken into account in the further planning of specific training.

The pathomechanisms of morbidity due to blood transfusions are not yet entirely understood. Elevated levels of red blood cell-derived microparticles (RMPs) are found in coagulation-related pathologies and also in stored blood. Previous research has shown that RMPs mediate transfusion-related complications by the intrinsic pathway. We hypothesized that RMPs might play a role in post-transfusion thrombotic complications by enhancing procoagulant activity also through the extrinsic pathway of coagulation.In this laboratory study, blood from 18 healthy volunteers was stimulated with microparticles from expired stored red blood cells. Various clotting parameters were recorded. Flow cytometry, enzyme-linked immunosorbent assays, and real-time polymerase chain reaction were used to investigate possible mediating mechanisms.The addition of RMPs shortened the clotting time from 194 to 161 seconds (p 0.001). After incubation with RMPs, there was increased expression of tissue factor (TF) on monocytes and in plasma. TF messenger RNA expression increased in a time-dependent and concentration-dependent manner. There was a significant induction of interleukin-1β and interleukin-6. After stimulation with RMPs, there was a significant increase in the number of activated platelets, an increased percentage of PAC-1/CD62P (procaspase activating compound-1/platelet surface P-selectin) double-positive platelets, and an increased number of platelet-neutrophil duplets and platelet-monocyte duplets, indicating enhanced interaction of platelets with neutrophils and monocytes. Levels of CXCL-8 (C-X-C motif chemokine ligand 1) and interleukin-6 were significantly higher after treatment with RMPs.Our results suggest that RMPs trigger coagulation through TF signaling, induce the secretion of proinflammatory cytokines, and induce cell-cell interaction between platelets and neutrophils. Thus, under certain conditions, RMPs could play a role in post-transfusion complications through these mechanisms.

The mechanism of preferential CO oxidation in H2-rich gas (PROX) is investigated over three different catalyst systems: supported platinum (in particular Pt/gamma-Al2O3), a supported bimetallic catalyst (Pt3Sn/Vulcan) and supported gold (in particular Au/alpha-Fe2O3). Compared to standard Pt catalysts which require temperatures above 150°C to operate at reasonable rates, the latter low temperature PROX catalysts are characterized by a combination of facile oxygen adsorption and largely inhibited hydrogen adsorption under reaction conditions. This can be achieved either by an active material that is inert for both, hydrogen and oxygen adsorption, but allows CO adsorption, and where oxygen adsorption proceeds on the support material (i.e., Au/Fe2O3), or by a material that would be active for adsorption of all reaction partners, but which is blocked for hydrogen and consequently also for oxygen adsorption by a CO adlayer. In all of these cases the oxidation reactions will take part at the interface between the different areas, or via a spill-over process and the reaction is not limited by CO desorption, which is the limiting factor for the Pt catalysts at temperatures below 150°C. On Pt/gamma-Al2O3 the rather constant selectivity is explained by a saturation coverage of COad which is maintained over a large range operation conditions. For the low-temperature catalysts the selectivity is also very high due to the high activation barrier for the dissociative adsorption of hydrogen. However, on the latter systems the selectivity decreases very fast at decreasing pCO or increasing temperatures as a result of the reduced CO surface coverage. All investigated systems show a more or less severe tendency for deactivation during time on-stream, but the reasons and also the degree of reversibility are very different. In experiments with more realistic simulations of methanol reformer gas (i. e., containing CO2 and H2O), it is found that the platinum-based systems suffer from large H2O-contents, which decrease the selectivity significantly, wheras Au/alpha-Fe2O3 is more sensitive to CO2.For Pt and Au various support materials are compared, but none of them appears to be significantly superior to the originally employed Pt/gamma-Al2O3 or Au/alpha-Fe2O3 catalysts.