Steatohepatitis induces significant portal hypertension (PHT) in the absence of fibrosis, associated with an increase in mesenteric arterial and portal venous flow, arterial hyporesponsiveness to vasoconstrictors and a decrease in MABP, indicating the presence of splanchnic vasodilation and hyperdynamic circulation. These alterations resemble those seen in cirrhotic PHT.

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Plasminogen activator inhibitor 1 (PAI-1) is the main inhibitor of tissue-type and urokinase-type plasminogen activator. A 4G/5G polymorphism in the promoter region of the PAI-1 gene has been reported to enhance the plasma levels of PAI-1. In particular, the 4G allele (guanosine deletion) has been linked with increased plasma PAI-1 levels, which may lead to impaired activity of the fibrinolytic system, thus increasing the incidence of thrombotic events. The aim of this case-control study was to analyze whether variants of the PAI-1 promotor genotype 4G/4G, 4G/5G and 5G/5G, in particular the 4G/5G-variant, constitute an independent risk factor of cerebral venous thrombosis (CVT). A total of 136 consecutive patients with proven CVT were compared to 1,054 DNA specimens of healthy controls from a population-based cohort. PAI-1 promotor polymorphisms were evaluated using polymerase chain reaction. No significant association of CVT with PAI-1 4G/5G was found in either the additive (OR 1.04; 95 % CI 0.78-1.38) or in the dominant model (OR 1.24; 95 % CI 0.72-2.13). Also, the prevalence of the other genotypes (4G/4G and 5G/5G) in patients was not significantly different from controls. When considering the variants of the PAI-1 promoter genotype in combination with known genetical thrombophilias, no differences were found either. As was expected, the prothrombin (G20210A) genotype was confirmed as an independent risk factor for CVT. We conclude that the 4G allele of the PAI-1 polymorphism does not increase the risk of CVT in adults.

Abstract. Numerical investigations of hydraulic turbo machines under steady-state conditions are state of the art in current product development processes. Nevertheless allow increasing computational resources refined discretization methods, more sophisticated turbulence models and therefore better predictions of results as well as the quantification of existing uncertainties. Single stage investigations are done using in-house tools for meshing and set-up procedure. Beside different model domains and a mesh study to reduce mesh dependencies, the variation of several eddy viscosity and Reynolds stress turbulence models are investigated. All obtained results are compared with available model test data. In addition to global values, measured magnitudes in the vaneless space, at runner blade and draft tube positions in term of pressure and velocity are considered. From there it is possible to estimate the influence and relevance of various model domains depending on different operating points and numerical variations. Good agreement can be found for pressure and velocity measurements with all model configurations and, except the BSL-RSM model, all turbulence models. At part load, deviations in hydraulic efficiency are at a large magnitude, whereas at best efficiency and high load operating point efficiencies are close to the measurement. A consideration of the runner side gap geometry as well as a refined mesh is able to improve the results either in relation to hydraulic efficiency or velocity distribution with the drawbacks of less stable numerics and increasing computational time. IntroductionThe increasing availability of computer resources allow the use of more accurate numerical schemes such as advanced turbulence models or higher discretization of the model domain. Therefore the Norwegian University of Science and Technology and Lulea University of Technology jointly are organizing a set of workshops to determine the state of the art of high head Francis turbine simulation. As the first of three upcoming workshops the present one is aimed at steady state simulations of a model turbine in three different operating points. In the pending workshops more sophisticated investigations like transient operating conditions and fluid structure interactions are investigated.Voith Hydro, as one of the world's leading manufactures in the field of hydropower equipment and services, gathered a broad experience in hydraulic model test and numerical simulations. Increasing demands of computational fluid dynamics (CFD) to support the hydraulic development process lead to a continuous improvement of computer resources and simulation methods. To validate the current development process the provided geometry is used as an input for the in-house mesh and setup procedure. The numerical results are validated with experimental data and can also be compared with the results of other participants.

Physiological processes are regulated by nonlinear dynamical systems. Various nonlinear measures have frequently been used for characterizing the complexity of fractal time signals to detect system features that cannot be derived from linear analyses. We analysed human balance dynamics ranging from simple standing to balancing on one foot with closed eyes to study the inherent methodological problems when applying fractal dimension analysis to real-world signals. Higuchi dimension was used as an example. Choice of measurement and analysis parameters has a distinct influence on the computed dimension. Noise increases the fractional dimension which may be misinterpreted as a higher complexity of the signal. Publications without specifying the parameter setting, or without analysing the noise-sensitivity are not comparable to findings of others and therefore of limited scientific value.

A study of the unsteady flow in an axial flow turbine stage with a second stator blade row is presented. The low aspect ratio blades give way to a highly three-dimensional flow which is dominated by secondary flow structures. Detailed steady and unsteady measurements throughout the machine and unsteady flow simulations which include all blade rows have been carried out. The presented results focus on the second stator flow. Secondary flow structures and their origins are identified and tracked on their way through the passage. The results of the time-dependent secondary velocity vectors as well as flow angles and Mach number distributions as perturbation from the time-mean flow field are shown in cross-flow sections and azimuthal cuts throughout the domain of the second stator. At each location the experimental and numerical results are compared and discussed. A good overall agreement in the time-dependent flow behaviour as well as in the secondary flow structures is stated. ' fluctuation

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This paper presents an approach to optimize the geometry of turbomachinery blades utilizing an automated optimization loop. Optimization examples of turbomachinery blade geometries with selected objective functions and a set of design variables are introduced. The presented optimization examples are performed for a 1.5-stage turbine test case. The blade geometries are fully parameterized, enabling three-dimensional changes to the blade shape during the optimization. Therefore various non-physical and physical parameters such as stacking line or stagger angle can be selected as design variables. Three-dimensional steady-state numerical flow simulations and a sensitivity equation method are part of the optimization process. The design sensitivities used within the optimization are obtained by numerically solving the analytical sensitivity equations. This optimization scheme uses the same numerical method for the flow simulation and for the computation of the sensitivity equation. A Navier-Stokes flow solver, which has especially been designed for turbomachinery applications was used for the implementation of the sensitivity equation method. The focus of this paper is on the application of the described optimization strategy to turbomachinery flows. The presented optimization examples are used to demonstrate and to discuss the capabilities of this approach.