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Purpose: To assess the impact of perioperative blood transfusion on overall and disease-free survival in patients undergoing curative resection for cholangiocarcinoma. Methods: In a single-center study, 128 patients undergoing curative resection for cholangiocarcinoma between 2001 and 2010 were assessed. The median follow-up period was 19months. Transfused and nontransfused patients were compared by Cox regression and propensity score analyses. Results: Overall, 38 patients (29.7%) received blood transfusions. The patient characteristics were highly biased with respect to receiving transfusions (propensity score 0.69±0.22 vs. 0.11±0.16, p

Future space missions will demand greater capabilities regarding the processing of sensor data on onboard computers of satellites than current space technology can provide. Limited downlink bandwidth, high resolution sensors and more rigid real-time control algorithms, dedicated to increase satellite autonomy, drive the need for growing onboard computing performance. To overcome these challenges, new high-performance onboard computers are necessary, leading to an increased consideration of Commercial-Of-The-Shelf (COTS) components. The DLR project Scalable Onboard Computing for Space Avionics (ScOSA) targets these challenges with a complex onboard computer design consisting of space-qualified and COTS computing devices, arranged as heterogeneous SpaceWire-interconnected grid computer in space. However, the utilization of COTS components in the harsh space environment imposes new challenges on the system. Therefore, Fault Detection Isolation and Recovery (FDIR) mechanisms are important functionalities of systems like ScOSA. These enable the preservation of the demanded dependability levels for an embedded system in space. To ensure this dependability, the FDIR subsystem configuration requires a detailed analysis regarding potential faults in the system. For this purpose, we employed Dynamic Fault Tree (DFT) analysis, a methodology which is used to model faults and their temporal propagation through an onboard computer. With this paper, we contribute a new building block for showing the applicability of DFT analysis and for closing the gap between theory and practical application of DFTs. The quantitative results of the analysis of the contribution of the ScOSA FDIR subsystem to the overall system reliability are taken as baseline for a discussion on how to effectively improve the system's reliability further. To showcase the methodology, an earth observation low earth orbit use case scenario is defined and the by FDIR means enforced processing system of the Xilinx Zynq SoC computing devices with a DFT analysis evaluated.

Development, validation and application of a profiling methodology for synthetic cannabinoids targeting (1) the chromatographic impurity signatures, providing deeper insights into the manufacturing methods including the synthesis pathway, educts, reagents or batch sizes and (2) the analysis of the stable isotopes of the main components to reveal links between samples that were synthesized using educts with a specific isotopic composition.

Purpose: This study assessed the diagnostic accuracy of C-reactive protein (CRP) after gastroesophageal cancer resection for postoperative inflammatory complications (PIC). Methods: The clinical data and CRP values of patients operated on for gastroesophageal cancer surgery between 1997 and 2009 were retrospectively analyzed. The results of this study were compared with published data using a meta-analytic approach for diagnostic outcomes. Results: Of 210 patients included in the study, 59 developed PIC (28.1%; 95% CI: 22.5-34.5%). On the postoperative day (POD) 4 and 7, CRP had the best diagnostic accuracy for PIC (AUC 0.77; 95% CI, 0.64-0.91, AUC 0.81; 95% CI, 0.71-0.91). Using a cut-off value of 141mg/L (95% CI, 131-278mg/L) for CRP on POD 4, the sensitivity was 0.78 (95% CI, 0.55-0.91), the specificity was 0.70 (95% CI, 0.53-0.83) and the NPV was 0.89 (95% CI, 0.77-0.95). The in-hospital mortality rate was 3.3% (95% CI, 1.5-6.9%). In a diagnostic meta-analysis that included two additional studies, CRP had a significant predictive value after POD 3. Conclusion: There is limited evidence for the diagnostic accuracy of CRP levels for PIC after gastroesophageal cancer surgery. CRP levels on POD 4 might be useful to rule out PIC, but its diagnostic accuracy is moderate at best. For clinical routine use CRP levels are clearly not sufficient to predict PIC and have to be interpreted in the context of the whole clinical picture

Reliability engineering is an integral part in the design of safety critical systems. Especially spacecraft that cannot receive physical maintenance once delivered into orbit heavily require a fault tolerant design approach. In order to overcome these challenges, concepts from the domain of Fault Detection, Isolation and Recovery (FDIR) are employed. With this paper we present our approach for bringing Model Based Systems Engineering into the realm of reliability engineering using the Virtual Satellite (VirSat) framework. The tool we are developing for this purpose is called VirSat FDIR. In this paper, we discuss a Conceptual Data Model for modelling important aspects of the FDIR domain that we have conceived and implemented for VirSat FDIR. It supports modelling of FDIR faults, recovery, analysis and requirements. We further discuss how these models can be actively used for the purpose of generation of FDIR artefacts and the process of Verification and Validation.

Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2018; Aachen 1 Online-Ressource (XV, 203 Seiten) : Illustrationen, Diagramme, Karten (2018). = Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2018, The Nagssugtoqidian Orogen in the Tasiilaq region of South-East Greenland, is a roughly southeast-northwesttrending, ~200 km wide Paleoproterozoic collisional orogen. It predominantly consists of a variety of Archean and Paleoproterozoic rocks, which were variably affected by several stages of deformation and metamorphism. The orogen has been subdivided into three different terranes. From north to south, these are the medium-pressure granulite-facies Schweizerland Terrane, the mainly high-pressure amphibolite-facies Kuummiut Terrane and the low-pressure amphibolite-facies Isertoq Terrane with the calc-alkaline Ammassalik Intrusive Complex. In the Kuummiut Terrane, variably retrogressed high-pressure mineral assemblages are preserved within mafic dykes, as well as boudins and boudinaged layers of mafic to ultramafic supracrustal rock in TTG gneiss. These mineralassemblages had previously not been investigated in much detail, but may provide important insight into the conditions of subduction, metamorphism and exhumation in the Paleoproterozoic, an era from which the geothermal regimes and nature of plate-tectonic processes are not well understood and high-pressure rocks are scarce. Within the framework of a larger expedition program to South-East Greenland, this thesis investigated the mineral textural evolution, PT-path and geochronology of variably retrogressed eclogite-facies rocks of the Kuummiut Terrane, via detailed petrological and mineral textural analysis, bulk-rock and mineral chemistry, conventional geothermobarometry, pseudosection modelling, and U-Pb isotopic dating. Well-equilibrated high-pressure and amphibolite-facies mineral assemblages, with only minor replacement textures, were found in garnet-pyroxenite, garnet-amphibolite and garnet-kyanite schist. Retrogressed eclogite, in contrast, is characterized by complex mineral reaction textures and the formation of two chemically and mineralogically distinct domains, leading to domainal equilibration volumes. A clinopyroxene domain is dominated by a fine-grained, worm-like to globular, diopsideplagioclase symplectite, which is often intergrown with and partially replaced by a coarser-grained hornblende-plagioclase symplectite. The fine-grained symplectite is interpreted to have grown at the expense of omphacite, which is only preserved in a Na-rich retrogressed eclogite sample. In a garnet domain, coarse-grained garnet is surrounded and variably pseudomorphed by corona-texturedplagioclase ± amphibole ± clinopyroxene ± orthopyroxene.Geothermobarometry and pseudosection modelling, in combination with the various Mineral textures, reveal evidence for four metamorphic stages along a clockwise PT-path. Ca-rich cores of large garnet grains in retrogressed eclogite are interpreted as prograde in origin and yield PTconditions of 14-19 kbar and 600-750 °C (I), followed by eclogite-facies metamorphism at 17-19 kbar and 740-810 °C (II). The retrograde PT-evolution is initially characterized by near-isothermal decompression to high-pressure granulite-facies conditions of 13.8-15.4 kbar and 760-880 °C (III), with subsequent decompression and minor cooling to high-pressure amphibolite-facies conditions of 8.8-10.9 kbar and 660-840 °C (IV). The PT-path implies that the Kuummiut Terrane probablyexperienced an initially rapid, tectonically driven exhumation. Furthermore, a large degree in consistency in the PT-data for the variably retrogressed high-pressure rocks suggests that they underwent the same metamorphic history, with the degree of retrogression and type of replacement assemblage mainly being controlled by fluid activity.LA-SF-ICP-MS U-Pb dating was carried out on zircon, monazite, titanite and rutile from retrogressed eclogite and the garnet-kyanite schist. A large range in 207Pb/206Pb dates between 2634 ± 63 and 1617 ± 91 Ma has been obtained, of which zircon yields the oldest and rutile the youngest dates. Detrital zircon in garnet-kyanite schist gives Archean to Paleoproterozoic dates and confines the maximum deposition of the precursor to the metasediment at 2107 ± 21 Ma. In retrogressed eclogite, the oldest zircon dates at 2146 ± 63 to 2092 ± 22 Ma are proposed to reflect the age of dyke emplacement into the Archean TTG gneiss. Dyke emplacement and deposition of supracrustal rocks most likely occurred near-contemporaneously during Paleoproterozoic extension and basin formation, as indicated by overlapping dates for detrital and magmatic zircon. The remaining data characterize the metamorphic evolution of the Kuummiut Terrane, about 200 m.y. after dyke emplacement. Consistent metamorphic dates between 1891 ± 10 and 1882 ± 3 Ma are obtained from the majority of the zircon, monazite and titanite analyses. The REE and U-Pb systematics in zircon indicate decoupling during retrograde metamorphism, with the REE patterns typical of zircon growth at eclogite-facies conditions, whereas the U-Pb dates and microtextures indicate recrystallization at high-pressure amphibolite-facies conditions. Based on previous studies and a similar decoupling in the magmatic zircons, the dates are interpreted to reflect mineral growth and recrystallization during high-pressure amphibolite-facies metamorphism. Regional medium-pressure amphibolite-facies metamorphism, associated with the collision of the Rae and North Atlantic cratons, is reflected by the 1872 ± 70 to 1821 ± 31 Ma monazite and titanite dates. Afterwards, the Kuummiut Terrane experienced relatively slow erosion-controlled cooling, with only minor thermal perturbations, as identified via rutile cooling ages at 1793 ± 10 Ma, 1738 ± 14 to 1720 ± 12 Ma, 1645 ± 63 Ma and 1617 ± 91 Ma. This thesis shows that a combination of different datasets from several variably retrogressed lithologies, rather than just examining eclogite-facies mineral assemblages, provides an invaluable tool for the characterization of the tectonometamorphic evolution of a Paleoproterozoic collisional orogen., Published by Aachen

Component-based harmonic studies in public Low Voltage grids require realistic models of individual loads as well as their typical penetration ratios. As fundamental basis for the development of comprehensive models for residential users, this paper identifies the most commonly used household loads in Colombia. The loads are classified according to their Power Factor Correction (PFC) circuit topology in no-PFC, passive-PFC and active-PFC devices, and a comprehensive set of loads is selected. Their behavior in terms of harmonic emission is characterized by intensive lab measurements with systematically varied supply voltage distortion. Based on several indices, the suitability of different frequency-domain modeling approaches (e.g. constant current source, decoupled and coupled Norton models) is assessed. Los estudios de armónicos en redes de baja tensión requieren el desarrollo de modelos realistas de cargas individuales así como el conocimiento de sus niveles típicos de penetración. Como base para el desarrollo de modelos en frecuencia, este artículo identifica las cargas no lineales más comunes que se usan en redes residenciales de Colombia. Estas cargas se clasifican de acuerdo con la topología de su circuito de corrección de factor de potencia (PFC) en no-PFC, PFC-pasivos y PFC-activos, y se selecciona un grupo representativo de cargas para cada caso. El comportamiento de la distorsión armónica para cada grupo se caracteriza a través de mediciones en laboratorio variando sistemáticamente la distorsión en tensión. Finalmente, se calculan varios indicadores para evaluar la conveniencia de los diferentes modelos en frecuencia (fuente de corriente constante, Norton acoplado y desacoplado) para cada grupo de cargas.

This talk shares our experience about setting up Tycho and Maven. Using Tycho and Maven in your build infrastructure can be very beneficial, but first it needs to be set up. In fact, this is the real challenge. Unfortunately, there is no real state-of-the-art or best practice about how to use this technology. Particularly, only little documentation exists. Most likely this is a consequence of everyone's individual project requirements and thus not allowing for the one ultimate answer.

Thermoplastische Kunststoffe werden zur Steigerung der mechanischen Eigenschaften häufig mit Kurzfasern verstärkt, wodurch sich jedoch eine anisotrope Eigenschaftscharakteristik einstellt. Dies führt oftmals zu ungewohntem Werkstoff- und Bauteilverhalten. Die Fertigungsparameter und -randbedingungen im Spritzgießprozess besitzen einen großen Einfluss auf lokale Faserorientierungen, wovon auch die globalen Bauteileigenschaften abhängen. Für eine werkstoffgerechte Auslegung von derartigen Bauteilen sind tiefgreifende Verständnisse über die mechanischen, thermischen und rheologischen Eigenschaften sowie die Kopplung von Spritzgieß- und Bauteilsimulation unerlässlich. Diese sogenannte integrative Simulation wird am Beispiel eines Strukturbauteiles aufgezeigt.