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Novel treatment options for portal hypertension

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Gastroenterology Report 2017年第2期5卷 90-103,I0001页

作者： philipp Schwabl Wim Laleman Division of Gastroenterology and hepatology Department of Internal Medicine IIIMedical University of ViennaViennaAustria Department of Gastroenterology and hepatology University Hospitals LeuvenKU LeuvenLeuvenBelgium

Portal hypertension is most frequently associated with cirrhosis and is a major driver for associated complications,such as variceal bleeding,ascites or hepatic *** such,clinically significant portal hypertension forms the prelude to decompensation and impacts significantly on the prognosis of patients with liver *** present,non-selective bblockers,vasopressin analogues and somatostatin analogues are the mainstay of treatment but these strategies are far from satisfactory and only target splanchnic *** contrast,safe and reliable strategies to reduce the increased intrahepatic resistance in cirrhotic patients still represent a pending *** recent years,several preclinical and clinical trials have focused on this latter component and other therapeutic *** this review,we highlight novel data in this context and address potentially interesting therapeutic options for the future.

关键词： portal hypertension hepatic venous pressure gradient non-selective b-blockers nitric oxide angiogenesis statins farnesoid X receptor renin-angiotensin-aldosterone

Evolutionary ecology of chemosensation and its role in sensory drive

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Current Zoology 2018年第4期64卷 525-533页

作者： Laurel R. YOhE philipp BRAND Department of Ecology and Evolution Stony Brook University Stony Brook NY 11790 USA Department of Geology & Geophysics Yale University New Haven CT 06511 USA Department of Evolution and Ecology Center for Population Biology University of California Davis CA 95616 USA

All behaviors of an organism are rooted in sensory processing of signals from its environment, and nat ural selection shapes sensory adaptations to ensure successful detection of cues that maximize fitness. Sensory drive, or divergent selection for efficient signal transmission among heterogeneous environ ments, has been a useful hypothesis for describing sensory adaptations, but its current scope has pri marily focused on visual and acoustic sensory modalities. Chemosensation, the most widespread sensory modality in animals that includes the senses of smell and taste, is characterized by rapid evolu tion and has been linked to sensory adaptations to new environments in numerous lineages. Yet, olfac tion and gustation have been largely underappreciated in light of the sensory drive hypothesis. here, we examine why chemosensory systems have been overlooked and discuss the potential of chemo sensation to shed new insight on the sensory drive hypothesis and vice versa. We provide suggestions for developing a framework to better incorporate studies of chemosensory adaptation that have the po tential to shape a more complete, coherent, and holistic interpretation of the sensory drive.

关键词： chemical signaling chemoreceptor chemosensation sensory drive olfaction

The AiiDA-KKR plugin and its application to highthroughput impurity embedding into a topological insulator

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npj Computational Materials 2021年第1期7卷 108-116页

作者： philipp Rüßmann Fabian Bertoldoand Stefan Blügel Peter Grünberg Institut and Institute for Advanced Simulation Forschungszentrum Jülich and JARAD-52425 JülichGermany

The ever increasing availability of supercomputing resources led computer-based materials science into a new era of highthroughput ***,Pizzi et *** the AiiDA framework that provides a way to automate calculations while allowing to store the full provenance of complex workflows in a *** present the development of the AiiDA-KKR plugin that allows to perform a large number of ab initio impurity embedding calculations based on the relativistic full-potential Korringa-Kohn-Rostoker Green function *** capabilities of the AiiDA-KKR plugin are demonstrated with the calculation of several thousand impurities embedded into the prototypical topological insulator *** results are collected in the JuDiT database which we use to investigate chemical trends as well as Fermi level and layer dependence of physical properties of *** includes the study of spin moments,the impurity’s tendency to form in-gap states or its effect on the charge doping of the *** properties depend on the detailed electronic structure of the impurity embedded into the host crystal which highlights the need for ab initio calculations in order to get accurate predictions.

关键词： method topological embedding

A multi-layered policy generation and management engine for semantic policy mapping in clouds

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Digital Communications and Networks 2020年第1期6卷 38-50页

作者： Faraz Fatemi Moghaddam philipp Wieder Ramin Yahyapour Gesellschaft für wissenschaftliche Datenverarbeitung mbh Gottingen(GWDG) Germany Institute of Informatics Georg-August-UniversitatGottingenGermany

The long awaited cloud computing concept is a reality now due to the transformation of computer ***,security challenges have become the biggest obstacles for the advancement of this emerging technology.A well-established policy framework is defined in this paper to generate security policies which are compliant to requirements and ***,a federated policy management schema is introduced based on the policy definition framework and a multi-level policy application to create and manage virtual clusters with identical or common security *** proposed model consists in the design of a well-established ontology according to security mechanisms,a procedure which classifies nodes with common policies into virtual clusters,a policy engine to enhance the process of mapping requests to a specific node as well as an associated cluster and matchmaker engine to eliminate inessential mapping *** suggested model has been evaluated according to performance and security parameters to prove the efficiency and reliability of this multilayered engine in cloud computing environments during policy definition,application and mapping procedures.

关键词： Cloud computing Security Security management Policy management Access control Policy mapping

Tribological performance and microstructural evolution ofα-brass alloys as a function of zinc concentration

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Friction 2020年第6期8卷 1117-1136页

作者： Zhilong LIU philipp MESSER-hANNEMANN Stephan LAUBE Christian GREINER Institute for Applied Materials(IAM) Karlsruhe Institute of Technology(KIT)Karlsruhe 76131Germany KIT IAM-CMS MikroTribologie CentrumμTC Karlsruhe 76131Germany

Tailoring a material's properties for low friction and little wear in a strategic fashion is a long-standing goal of materials *** deformation plays a major role when metals are employed in a sliding contact;therefore,the effects of stacking fault energy and mode of dislocation glide need to be ***,we investigated how a decrease in the stacking fault energy affects friction,wear,and the ensuing sub-surface microstructure *** samples with increasing zinc concentrations of 5,15,and 36 wt%were tested in non-lubricated sphere-on-plate contacts with a reciprocating linear tribometer against Si3N4 *** the sliding distance from 0.5(single trace)to 5,000 reciprocating cycles covered different stages in the lifetime of a sliding *** the results among the three alloys revealed a profound effect of the zinc concentration on the tribological ***15 and CuZn36 showed similar friction and wear results,whereas CuZn5 had a roughly 60%higher friction coefficient(COF)than the other two ***15 and CuZn36 had a much smaller wear rate than *** dislocation motion in CuZn5 and CuZn15 allowed for dislocation self-organization into a horizontal line about 150 nm beneath the contact after a single trace of the *** feature was absent in CuZn36 where owing to planar dislocation slip band-like features under a 45°angle to the surface were *** results hold the promise to help guide the future development of alloys tailored for specific tribological applications.

关键词： brass tribology sliding contact microstructure stacking fault energy electron microscopy

Elucidating the dynamics of polymer transport through nanopores using asymmetric salt concentrations

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Nano Research 2022年第11期15卷 9943-9953页

作者： Martin Charron Lucas philipp Liqun he Vincent Tabard-Cossa Department of Physics University of OttawaOttawaON K1N 6N5Canada

While notable progress has been made in recent years both experimentally and theoretically in understanding the highly complex dynamics of polymer capture and transport through nanopores,there remains significant disagreement between experimental observation and theoretical prediction that needs to be *** salt concentrations,where the concentrations of ions on each side of the membrane are different,can be used to enhance capture rates and prolong translocation times of electrophoretically driven polymers translocating through a nanopore from the low salt concentration reservoir,which are both attractive features for single-molecule ***,since asymmetric salt concentrations affect the electrophoretic pull inside and outside the pore differently,it also offers a useful control parameter to elucidate the otherwise inseparable physics of the capture and translocation *** this work,we attempt to paint a complete picture of the dynamics of polymer capture and translocation in both symmetric and asymmetric salt concentration conditions by reporting the dependence of multiple translocation metrics on voltage,polymer length,and salt concentration *** asymmetric salt concentration conditions,we experimentally observe the predictions of tension propagation theory,and infer the significant impact of the electric field outside the pore in capturing polymers and in altering polymer conformations prior to translocation.

关键词： nanopore DNA translocation salt gradient tension propagation polymer transport

Identification of the Exchange Coefficient from Indirect Data for a Coupled Continuum Pipe-Flow Model

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Chinese Annals of Mathematics,Series B 2014年第3期35卷 483-500页

作者： Xinming WU philipp KGLER Shuai LU School of Mathematical Sciences Fudan University Institute for Applied Mathematics and Statistics University of Hohenheim Johann Radon Institute for Computational and Applied Mathematics (RICAM) Corresponding author. School of Mathematical Sciences Fudan University

Calibration and identification of the exchange effect between the karst aquifers and the underlying conduit network are important issues in order to gain a better understanding of these hydraulic systems. Based on a coupled continuum pipe-flow(CCPF for short) model describing flows in karst aquifers, this paper is devoted to the identification of an exchange rate function, which models the hydraulic interaction between the fissured volume(matrix) and the conduit, from the Neumann boundary data, i.e., matrix/conduit seepage velocity. The authors formulate this parameter identification problem as a nonlinear operator equation and prove the compactness of the forward mapping. The stable approximate solution is obtained by two classic iterative regularization methods, namely,the Landweber iteration and Levenberg-Marquardt method. Numerical examples on noisefree and noisy data shed light on the appropriateness of the proposed approaches.

关键词： CCPF model Landweber iteration Levenberg-Marquardt method

Viscoelasticity and shear resistance at the aggregate scale of structured and organic carbon-free Chernozems

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Pedosphere 2023年第5期33卷 754-764页

作者： Christoph hAAS Rainer hORN philipp SAGGAU Rainer DUTTMANN Institute for Plant Nutrition and Soil Science University of KielKiel 24118Germany Department of Geography Division of Landscape Ecology and Geoinformation SciencesUniversity of KielKiel 24118Germany

Soil rheology characterises the flow behaviour of soils at the particle-particle to aggregate *** sweep tests(ASTs)are often the method of choice for parameterizing soil flow properties,such as the shear strain values at the end of the linear viscoelastic range(i.e.,the deformation is mainly elastic)and at the yield point(i.e.,elastic equals plastic deformation).Samples from seven soil profiles and five soil depths of Chernozems,collected in the Maidanetske study area,close to Uman City of Ukraine,were analysed to evaluate the effect of soil organic carbon(SOC)on the parameters related to soil microstructural stability derived from *** organic carbon was removed with h_(2)O_(2)to determine the soil texture-dependent values of soil rheological properties,which were compared to the values determined for samples with intact water-stable *** shear resistance-related parameters increased for aggregated soil samples compared to SOC-free soil samples,indicating an increase in soil stability due to *** contrast,the values of the overall viscoelasticity and the shear strain were reduced for aggregated soil samples,indicating decreased soil *** functions were applied to predict the shear strain-dependent loss and storage moduli and shear stress values as a function of SOC *** particles(630–2000μm)and volumetric water content improved the *** conclude that increased SOC content,through the gluing and cementing effects of SOC and altered aggregate shapes compared to SOC-free soil materials,contributes to higher microstructural ***,the increased water content in the SOC-containing soil samples reversed soil strengthening *** was due to the fact that a more rapid increase in positive water pressure under shear stress weakened the samples and the spherical aggregates began to rotate more easily,thus loosing energy,when compared to platy particles of the SOC-free soil materials.

关键词： aggregation rheology shear strain shear stress soil organic carbon depletion soil stability

On the calibration of rotational augmentation models for wind turbine load estimation by means of CFD simulations

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Acta Mechanica Sinica 2020年第2期36卷 306-319页

作者： Belen Soledad Burgos Tafur Elia Daniele Bernhard Stoevesandt philipp Thomas Fraunhofer IWES Am Seedeich 4527572 BremerhavenGermany Flensburg University of Applied Sciences Wind Energy Technology InstituteNordstraße224943 FlensburgGermany

In this work the improved version of an engineering model which accounts for rotational augmentation effects by means of computational fluid dynamics(CFD)calibration is explored and *** on an analysis of the NREL Phase VI wind turbine,the novel modeling is presented,which uses as base line the formulation proposed by Chaviaropoulos and *** model is calibrated based on CFD simulations using *** corresponding correction of the two dimensional polars is straightforward implemented within MoWiT,an in-house software for load *** novel formulation results in improved lift and drag coefficients prediction in all considered cases,reducing the deviation with respect to the rotating CFD cases down to few *** optimal configuration including the correction for tip effects of Shen shows better agreements at the very tip of the *** the range of applicability for large wind turbine rotor blades based on a virtual 10MW rotor model is discussed.

关键词： calculation. rotational correction