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Background With an incidence up to 20 % biliary complications in the first year after liver transplantation (LT), these are still the main problems following a successful transplantation (TX). Reperfusion in LT is done via an antegrade flow through the portal vein and the hepatic artery as a standard. Retrograde reperfusion via the caval vein has shown to reduce the rate of initial graft nonfunction after LT but increase biliary complications. Retrograde reperfusion in combination with piggyback technique is the standard technique for liver transplantation in our center. The aim of this study was to compare the rate of biliary complications after LT with retrograde reperfusion in combination with piggyback technique to the literature.

The increasing availability of 10G Ethernet network capabilities challenges existing transport layer protocols. As 10G connections gain momentum outside of backbone networks, the choice of appropriate TCP congestion control algorithms becomes even more relevant for networked applications running in environments such as data centers. Therefore, we provide an extensive overview of relevant TCP congestion control algorithms for high-speed environments leveraging 10G. We analyzed and evaluated six TCP variants using a physical network testbed, with a focus on the effects of propagation delay and significant drop rates. The results indicate that of the algorithms compared, BIC is most suitable when no legacy variant is present, CUBIC is suggested otherwise.

There are many high-speed TCP variants with different congestion control algorithms, which are designed for specific settings or use cases. Distinct features of these algorithms are meant to optimize different aspects of network performance, and the choice of TCP variant strongly influences application performance. However, setting up tests to help with the decision of which variant to use can be problematic, as many systems are not designed to deal with high bandwidths, such as 10 Gbps or more. This paper provides an overview of pitfalls and challenges of realistic network analysis to help in the decision making process.

International audience; The EC project parMERASA (Multicore Execution of Parallelized Hard Real-Time Applications Supporting Analyzability) investigated timing-analyzable parallel hard real-time applications running on a predictable multicore processor. A pattern-supported parallelization approach was developed to ease sequential to parallel program transformation based on parallel design patterns that are timing analyzable. The parallelization approach was applied to parallelize the following industrial hard real-time programs: 3D path planning and stereo navigation algorithms (Honeywell International s.r.o.), control algorithm for a dynamic compaction machine (BAUER Maschinen GmbH), and a diesel engine management system (DENSO AUTOMOTIVE Deutschland GmbH). This article focuses on the parallelization approach, experiences during parallelization with the applications, and quantitative results reached by simulation, by static WCET analysis with the OTAWA tool, and by measurement-based WCET analysis with the RapiTime tool.

The measurement of kidney function after orthotopic liver transplantation (OLT) is still a clinical challenge. Cystatin C (CysC) has been proposed as a more accurate marker of renal function than serum creatinine (sCr). The aim of this study was to evaluate sCr- and CysC-based equations including the Chronic kidney disease (CKD)-EPI to determine renal function in liver transplant recipients. CysC and sCr were measured in 49 patients 24 months after OLT. The glomerular filtration rate (GFR) was calculated using the MDRD 4, the Cockroft-Gault, Hoek, Larsson, and the CKD-EPI equations based on sCr and/or CysC. As reference method, inulin clearance (IC) was estimated. Bias, precision, and accuracy of each equation were assessed and compared with respect to IC. Forty-five percent had a GFR

This paper presents the current application of numerical Fluid-Structure Interaction (FSI) simulation to the architectural and structural design of large umbrella structures and the work on generating atmospheric wind inflow conditions for numerical simulations. This article outlines a virtual design methodology for structures under the impact of fluctuating wind loads and provides results on worked examples

A new method for predicting static eccentricity in an induction machine with a non-uniform air gap is described. This procedure is based on a suitable system mode I for which the model parameters have to be identified. Under certain conditions, the mathematical model of the machine leads to an equation depending on speed, voltage, current and their derivatives. The parameters of the machine can be identified by a least-square algorithm. The basic concept of the identification method is that the mathematical parameters will be influenced by the static eccentricity because a non-uniform air gap will increase the inductance in all three phases of the machine. Practical results of air-gap eccentricity detection of a low-power motor are presented.

Multi-core processors are gaining a foothold in the domain of embedded automotive systems. The AUTOSAR Release 4.1 establishes a common standard for the use of multi-core processors in automotive systems. While interfaces and functionalities are well defined in the specification, the actual implementation is left open to the software manufacturers. We exploit this room that is left by the specification for the implementation of cross-core service calls. In this paper, we compare two opposite implementation approaches that can be used in shared-memory multi-core processors. The actual execution of a service call either takes place on the affected core, or on the invoking core. Our performance evaluations indicate an advantage of a lock-based approach with execution on the invoking core.

International audience; Engineers who design hard real-time embedded systems express a need for several times the performance available today while keeping safety as major criterion. A breakthrough in performance is expected by parallelizing hard real-time applications and running them on an embedded multi-core processor, which enables combining the requirements for high-performance with timing-predictable execution. parMERASA will provide a timing analyzable system of parallel hard real-time applications running on a scalable multicore processor. parMERASA goes one step beyond mixed criticality demands: It targets future complex control algorithms by parallelizing hard real-time programs to run on predictable multi-/many-core processors. We aim to achieve a breakthrough in techniques for parallelization of industrial hard real-time programs, provide hard real-time support in system software, WCET analysis and verification tools for multi-cores, and techniques for predictable multi-core designs with up to 64 cores.

The EC project parMERASA investigates techniques for the parallelization of industrial real-time applications from automotive, avionic, and construction machinery domains. The aim is to execute such applications on many-core processors with up to 64 cores. The system software plays a key role in the deployment of applications. However, requirements of application domains differ widely, and thus no general solution can be implemented. In this paper we present the cross-domain system architecture utilized in the parMERASA project to provide Runtime Environments (RTEs) for the three different domains. The approach eases the implementation of domain-specific RTEs through a generic kernel library that provides basic hardware abstractions and timing-analyzable synchronization mechanisms.

Background Literature is controversial whether organs from living donors have a better graft function than brain dead (BD) and non–heart-beating donor organs. Success of transplantation has been correlated with high-energy phosphate (HEP) contents of the graft. Methods HEP contents in heart, liver, kidney, and pancreas from living, BD, and donation after cardiac death in a pig model (n = 6 per donor type) were evaluated systematically. BD was induced under general anesthesia by inflating a balloon in the epidural space. Ten hours after confirmation, organs were retrieved. Cardiac arrest was induced by 9 V direct current. After 10 min of ventricular fibrillation without cardiac output, mechanical and medical reanimation was performed for 30 min before organ retrieval. In living donors, organs were explanted immediately. Freeze-clamped biopsies were taken before perfusion with Celsior solution (heart) or University of Wisconsin solution (abdominal organs) in BD and living donors or with Histidine-Tryptophan-Ketoglutaric solution (all organs) in non–heart-beating donors, after perfusion, and after cold ischemia (4 h for heart, 6 h for liver and pancreas, and 12 h for kidney). HEPs (adenosine triphosphate, adenosine diphosphate, adenosine monophosphate, and phosphocreatine), xanthine, and hypoxanthine were measured by high-performance liquid chromatography. Energy charge and adenosine triphosphate-to-adenosine diphosphate ratio were calculated. Results After ischemia, organs from different donor types showed no difference in energy status. In all organs, a decrease of HEP and an increase in hypoxanthine contents were observed during perfusion and ischemia, irrespective of the donor type. Conclusion Organs from BD or non–heart-beating donors do not differ from living donor organs in their energy status after average tolerable ischemia.

Background As organ shortage is increasing, the acceptance of marginal donors increases, which might result in poor organ function and patient survival. Mostly, organ damage is caused during brain death (BD), cold ischemic time (CIT) or after reperfusion due to oxidative stress or the induction of apoptosis. The aim of this study was to study a panel of genes involved in oxidative stress and apoptosis and compare these findings with immunohistochemistry from a BD and living donation (LD) pig model and after cold ischemia time (CIT). Methods BD was induced in pigs; after 12 h organ retrieval was performed; heart, liver and kidney tissue specimens were collected in the BD (n = 6) and in a LD model (n = 6). PCR analysis for NFKB1, GSS, SOD2, PPAR-alpha, OXSR1, BAX, BCL2L1, and HSP 70.2 was performed and immunohistochemistry used to show apoptosis and nitrosative stress induced cell damage. Results In heart tissue of BD BAX, BCL2L1 and HSP 70.2 increased significantly after CIT. Only SOD2 was over-expressed after CIT in BD liver tissue. In kidney tissue, BCL2L1, NFKB, OXSR1, SOD2 and HSP 70.2 expression was significantly elevated in LD. Immunohistochemistry showed a significant increase in activated Caspase 3 and nitrotyrosine positive cells after CIT in BD in liver and in kidney tissue but not in heart tissue. Conclusion The up-regulation of protective and apoptotic genes seems to be divergent in the different organs in the BD and LD setting; however, immunohistochemistry revealed more apoptotic and nitrotyrosine positive cells in the BD setting in liver and kidney tissue whereas in heart tissue both BD and LD showed an increase.