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Instant evaluation of contrast enhanced endoscopic ultrasound helps to differentiate various solid pancreatic lesions in daily routine

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World Journal of Clinical Cases 2019年第1期7卷 19-27页

作者： Klaus Kannengiesser reiner mahlke Frauke Petersen Anja Peters Torsten Kucharzik Christian Maaser Department of General Internal Medicine and Gastroenterology University Teaching Hospital Lueneburg Department of Pathology University Teaching Hospital Lueneburg

BACKGROUND Contrast enhanced harmonic endoscopic ultrasound(CEH-EUS) is a spreading technique; some studies have shown its value in the diagnosis of pancreatic adenocarcinoma using quantitative *** To examine the value of CEH-EUS for differentiating various pancreatic lesions in everyday routine with qualitative and quantitative *** Data of 55 patients with pancreatic lesions who underwent CEH-EUS were analysed retrospectively. Perfusion characteristics were classified by the investigator qualitatively immediately upon investigation, quantitative analysis was performed later on. Samples from fine needle aspiration(EUS-FNA) or surgical specimen served as gold *** CEH-EUS showed 39 hypoenhanced lesions, 3 non-enhanced and 13 hyperenhanced lesions. Concordance of the investigators qualitative classification of peak contrast enhancement with quantitative analysis later on was 100%, while other parameters such as arrival time, time to peak or area under the curve did not show additional value. 34 of 39 hypoenhanced lesions were pancreatic adenocarcinoma; of the hyperenhanced lesions 4 were inflammatory, 3 neuroendocrine carcinomas, 1 lymphoma, 1 insulinoma and 4 metastases(2 of renal cell carcinoma, 2 of lung cancer). Non-enhanced lesions showed up as necroses. Sensitivity for the detection of pancreatic adenocarcinoma was 100%,specificity 87.2% for hypoenhancement alone; in otherwise healthy pancreatic tissue all hypoenhanced lesions were pancreatic adenocarcinoma(sensitivity and specificity 100%, PPV and NPV for adenocarcinoma 100%).CONCLUSION This study again shows the excellent value of CEH-EUS in everyday routine for diagnostics of various focal pancreatic lesions suggesting that qualitatively assessed hypoenhancement is highly predictive for adenocarcinoma. Additional quantitative analysis of perfusion parameters does not add diagnostic yield. In case of the various hyperenhanced pancreatic lesions in our data set, histologic samp

关键词： Endoscopic ultrasound Contrast enhanced endoscopic ultrasound Pancreatic adenocarcinoma Neuroendocrine carcinoma Pancreatic metastases Lymphoma

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Origin of the deep fluids in the paleosubduction zones in western Tianshan:Evidence from Pb-and Sr-isotope compositions of high-pressure veins and host rocks

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Science China Earth Sciences 2005年第10期48卷 1627-1636页

作者： reiner Klemd Mineralogisches Institut Universit?t Würzburg Am Hubland 97074 Würzburg Germany

Fluids in the deep subduction zones play an important role in crust-mantle ex-change related to the subduction process. Identification of fluids origin, internal or external, can help us to evaluate the contribution of crust materials to mantle during this process. High-pressure veins, which developed in the western Tianshan HP-metamorphic belt extensively, are the direct products of the fluids in subduction zones. In western Tianshan, high-pressure veins and host rocks have overall Pb- and Sr-isotope compositions. At t = 340 Ma, the high-pressure metamorphic time, the ratios of 206Pb/204Pb, 207Pb/204Pb, 208Pb/204Pb and 87Sr/86Sr of high pressure veins are 17.122―18.431, 15.477―15.611, 37.432―38.689 and 0.70529―0.70705, and are 17.605―17.834, 15.508―15.564, 37.080―38.145 and 0.70522―0.70685 for host rocks. However, high-pressure veins show a much larger variation in Pb-isotope composi-tions than host rocks. Plots of samples are distributed roughly along a line parallel to and far away from the Northern Hemisphere reference line (NHRL) on the plot of 206Pb/204Pb vs 207Pb/204Pb. On the plot of 206Pb/204Pb vs 208Pb/204Pb, plots of data are distributed nearby mid-ocean-ridge basalts (MORB) area or along a line parallel to and not far away from NHRL, which shows that the data plots are farther away from MORB and ocean island basalts (OIB) areas on the plot of 206Pb/204Pb vs 207Pb/204Pb than on the plot of 206Pb/204Pb vs 208Pb/204Pb. The compositions of Pb- and Sr-isotopes of these high-pressure metamorphic rocks are between that of enriched mantle 1(EMI) and of sediments or upper crust. A notable characteristic can be seen from plots of Pb-isotope ratio vs Pb-isotope ratio and 206Pb/204Pb vs 87Sr/86Sr that array of plots shows an evident tendency of mixture of two end members. Ratios of Rb/Ba, Ce/Pb, Nb/U and Ta/U of high-pressure veins and host rocks are between that of OIB or MORB and that of conti-nental crust, which indicates that continental crust materials probably

关键词： deep fluids in the subduction zones, Pb- and Sr-isotope, high pressure vein, host rock, western Tianshan.

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Darwinian selection within an individual or somatic selection: facts and models

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Journal of Molecular Cell Biology 2019年第8期11卷 719-722页

作者： reiner A.Veitia Institut Jacques Monod Universite Paris Diderot 75013 Paris France Universite Paris-Diderot 75013 Paris France

There are known cases where a cell sub-population bearing a selective advantage tends to or eventually replaces another cell subpopulation within an organism. This process is supposed to underlie the purging of the most frequent mitochon-drial DNA pathogenic variant from leuko-cytes and other tissues. It is also likely to explain the normal increase of sex chromo-some aneuploidy in human leukocytes with age or under pathological conditions and the expansion of a cell subpopulation after the spontaneous in vivo reversion to normal of an inherited pathogenic variant.

关键词： Darwinian selection facts models

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EHD friction properties of ISO VG 320 gear oils with smooth and rough surfaces

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Friction 2020年第1期8卷 164-181页

作者： Balasubramaniam VENGUDUSAMY Claus ENEKES reiner SPALLEK Klüber Lubrication München SE&Co.KG Geisenhausenerstraße 7Munich 81379Germany

The elastohydrodynamic(EHD)friction properties of seven ISO VG 320 gear oils including three polyalphaolefins(PAOs),three polyglycols(PG)and a mineral oil have been investigated in rolling/sliding conditions at six different temperatures and three *** thickness,Stribeck and traction curves have been generated using a ball‐on‐disc *** thickness results are in agreement with previous work that it is primarily controlled by pressure‐viscosity coefficient and viscosity of *** results with smooth surface show that all oils experience significant shear heating leading to friction reduction at higher strain rates or lambda ratios but only PGs reach limiting friction whereas mineral oil and PAOs do *** curves obtained at different temperatures and roughnesses enable simulating an extensive range of lubrication regimes and allow isothermal friction correction for shear *** curves with rough surfaces show an increase in friction in the lambda range of 0.5–3.5,where asperity separation varies from partial to full–indicating that roughness effects can be expected even under full film *** increase in friction is attributed to formation of a micro‐EHD region,and is seen only with mineral oil and PAOs whereas not with *** results also highlight how EHD friction properties of different family of fluids could be influenced by roughness effects,and the possible mechanisms are discussed.

关键词： ISO VG 320 gear oil roughness effect film thickness friction EHD micro‐EHD

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AFF3:a new player in maintaining XIST monoallelic expression

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Journal of Molecular Cell Biology 2019年第9期11卷 723-724页

作者： reiner A.Veitia Institut Jacques Monod Universite Paris DiderotParisFrance Universite Paris-Diderot ParisFrance

The existence of highly differentiated X and Y chromosomes in mammals raises the issue of X-linked gene dosage compensation between XX females and XY males to avoid what would be similar to a monosomy X in males(Veitia et al.,2015).Inactivation of one copy of the X chromosomes in females provides a dosage-compensation mechanism equalizing the expression of X-linked genes in males and females(Ohno et al.,1959;Lyon,1961).

关键词： dosage al. differentiated

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CFD-simulation of a circulating fluidized bed riser

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Particuology 2009年第4期7卷 283-296页

作者： Ernst-Ulrich Hartge Lars Ratschow reiner Wischnewski Joachim Werther Hamburg-University of Technology Institute of Solids Process Engineering and Particle TechnologyD-21071 HamburgGermany

In the current work, a model of the fluid mechanics in the riser of a circulating fluidized bed （CFB） has been implemented using computational fluid dynamics （CFD）. The model developed shall be used in future as the basis of 3D-reactor model for the simulation of large scale CFB combustors. The two-fluid model （TFM） approach is used to represent the fluid mechanics involved in the flow. The computational implementation is accomplished by the commercial software FLUENT. Different closure formulations are tested on a simplified geometry. Two different turbulence formulations, namely the swirl modified RNG k-e model and the Realizable k-e model, are tested in combination with two different approaches to solid phase turbulence, namely the dispersion and per phase approach. One focus of the current work is put on the study of different drag correlations. Besides the drag correlations by Syamlal et al. [Syamlal, M., Rogers, W., ＆ O＇Brien, T. J. （1993）. MFIX documentation theory guide. Technical Report DOE/METC-9411004, U.S. Department of Energy （DOE）. Morgantown Energy Technology Center： Morgantown, WV] and Gidaspow [Gidaspow, D. （1994）. Multiphaseflow andfluidization. New York： Academic Press] the EMMS model has been used to determine the momentum exchange between the two phases. The resulting formulation is then used to simulate a 1-m × 0.3-m cold CFB setup and is validated by experimental results [Schlichtharle, P. （2000）. Fluid dynamics and mixing of solids and gas in the bottom zone of circulating fluidized beds. Unoublished doctoral dissertation, Technische Universitaet Hamburg-Harburg, Shaker Verlag： Aachen].

关键词： Circulating fluidized bed Two-fuid model EMMS model Drag correlations

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Bauxite washing for the removal of clay

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International Journal of Minerals,Metallurgy and Materials 2014年第11期21卷 1045-1051页

作者： Ishaq Ahmad Ernst-Ulrich Hartge Joachim Werther reiner Wischnewski Department of Mining Engineering University of Engineering and TechnologyPeshawar-25120 Pakistan Institute of Solids Process Engineering and Particle Technology Hamburg University of Technology (TUHH)Denickestrasse 1521073 Hamburg Germany Norsk Hydro Aluminum ASA Skφyen Oslo Norway

Clay impurities associated with bauxite negatively affect the Bayer process for alumina production. These impurities should be removed as far as possible by a beneficiation technique before the ore is used as feed for the Bayer process. In this current investigation, bauxite washing was conducted in the laboratory. Bauxite washing is a physical process that causes the disintegration and deagglomeration of the clay matrix, and bauxite is liberated from the clay（mainly rich in silica）. Subsequently, separation occurs with the assistance of wet screening at a predetermined cut size. Three techniques were investigated in the laboratory： drum washing, water-jet washing, and ultrasonic washing. Various operating parameters were investigated for drum washing and water-jet washing, including materials retention time, drum rotation speed, solid concentration, water-jet spray duration, pressure, and height. We concluded that the retention time of bauxite inside the drum at a solid concentration of 55wt% and a drum rotation speed of 31 r/min is the dominant parameter for the removal of clay from the bauxite surface.

关键词： beneficiation bauxite washing clay Bayer process

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Reactive gas-solids flows in large volumes—3D modeling of industrial circulating fluidized bed combustors

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Particuology 2010年第1期8卷 67-77页

作者： reiner Wischnewski Lars Ratschow Ernst-Ulrich Hartge Joachim Werther Hydro Aluminium AS Pyry Energy GmbH Institute of Solids Process Engineering and Particle Technology Hamburg University of Technology

A model is presented for the simulation of reactive gas-solids flows in large industrial reactors. Circulating fluidized bed （CFB） combustors with several thousands of cubic meters reaction volume are probably the largest reactors of this type. A semi-empirical modeling approach has been chosen to model the three-dimensional concentration distributions of gas and solids components and temperatures inside the combustion chamber of such boilers. Two industrial CFB boilers are investigated in detail： the 105 MWe Duisburg combustor in Germany and the 235 MWe Turow combustor in Poland. The semi-empirical model approach is described first. Then the model is used to show how the three-dimensional concentration and temperature fields are formed by the interaction of several local phenomena. Good agreement between simulation and measurements has been achieved.

关键词： Circulating fluidized bed Large-scale Combustion 3D modeling

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Simulation-supported measurements in large circulating fluidized bed combustors

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Particuology 2009年第4期7卷 324-331页

作者： Joachim Werther Ernst-Ulrich Hartge Lars Ratschow reiner Wischnewski Institute of Solids Process Engineering and Particle Technology Hamburg University of TechnologyD 21071 HamburgGermany Now with Pyry Energy GmbH HamburgGermany Now with Hydro Aluminium AS OsloNorway

The concept of simulation-supported measurement is suggested for the elucidation of processes occurring in the combustion chambers of large-scale circulating fluidized bed combustors where the desired information cannot be obtained by direct measurements. The concept is illustrated with the example of secondary air injection where the way the air is released, the penetration depth and the evenness of air distribution over the cross-sectional area of the combustion chamber are of interest. The measured information consists of lateral profiles of oxygen concentrations measured with gas sampling probes at two ports which were located 5 and 9 m, respectively, above the level of secondary air injection. The simulation is carried out on the basis of a 3D semi-empirical fluid-mechanical model of the circulating fluidized bed which is combined with models of gas and solids mixing, fuel distribution, devolatilization and combustion of char and volatiles. The combination of the simulation with the measurements yields a clear picture of the mechanism of secondary air injection, its penetration into the combustion chamber and its effect on the local combustion processes. The results confirm the usefulness of the concept of simulation-supported measurement for this application.

关键词： Fluidized bed Combustion Local measurements 3D modeling

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Software development processes in ocean system modeling

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International Journal of Modeling, Simulation, and Scientific Computing 2022年第2期13卷 47-69页

作者： reiner Jung Sven Gundlach Wilhelm Hasselbring Software Engineering Group Department of Computer Science Kiel UniversityKielGermany

Scientific modeling provides mathematical abstractions of real-world systems and builds software as implementations of these mathematical *** science is a multidisciplinary discipline developing scientific models and simulations as ocean sys-tem models that are an essential research *** software engineering and information systems research,modeling is also an essential *** particular,business process modeling for business process management and systems engineering is the activity of representing processes of an enterprise,so that the current process may be analyzed,improved and *** this paper,we employ process modeling for analyzing sci-entific software development in ocean science to advance the state in engineering of ocean system models and to better understand how ocean system models are developed and maintained in ocean *** interviewed domain experts in semi-structured inter-views,analyzed the results via thematic analysis,and modeled the results via the Busi-ness Process Modeling Notation(BPMN).The processes modeled as a result describe an aspired state of software development in the domain,which are often not(yet)*** enables existing processes in simulation-based system engineering to be improved with the help of these process models.

关键词： Scientific modeling software development processes process modeling the-matic analysis

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