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Progress in Natural Science:Materials International 2007年第7期17卷 798-802页

作者： Kermal Topac Ertan christoph Hemleben Institute of Geology University of TuebingenD-72076Germany

Living planktonic foraminifera(PF)samples from the Okinawa Trough of the northwestern Pacific Ocean were taken for DNA *** SSU rDNA sequences of two PF species,Globigerina *** Pulleniatina obliquiloculata collected at Station WP01,were obtained and compared with those from the southwestern Pacific *** small differences(<0.7%—1.2% for P. obliquiloculata,and 0.3% for Globigerina sp.)were found between samples from the north-and south-western Pacific Ocean areas and this molecular evidence supported that these micropaleontological species are the same species,which implies that the West Pacific Ocean circulation system influences the planktonic foraminiferal gene communication.

关键词： the northwestern Pacific Ocean planktonic foraminifera Pulleniatina obliquiloculata Globigerina sp. SSU rD-NA

New Microalloyed Steels for Forgings

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Journal of Iron and Steel Research International 2011年第S1期18卷 104-111页

作者： christoph Keul Wolfgang Bleck Department of Ferrous Metallurgy RWTH Aachen UniversityGermany

Microalloyed steels for forging applications have been newly developed in order to increase strength and toughness properties which thereby give the possibility for light weight *** properties of these steels are set up by a controlled cooling directly from the forging heat without an additional heat *** aim can be achieved on the one hand by a further development of precipitation hardening ferritic pearlitic steels (AFP-steel) due to an extended use of microalloying elements (AFP-M steel) and on the other hand by microalloyed steels which employ a bainitic microstructure (HDB steel).To adjust the targeted microstructure the temperature control has to be assured down to approx.500℃ for the AFP-M steels and down to approx.300℃ for the HDB steels.

关键词： forgings bainite microalloying controlled cooling

Treatment of eosinophlic esophagitis with swallowed topical corticosteroids

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World Journal of Gastroenterology 2020年第36期26卷 5395-5407页

作者： Simon Nennstiel christoph Schlag Klinikum rechts der Isar der Technischen Universität München Klinik und Poliklinik für Innere Medizin IIMunich 81675Germany

Eosinophilic esophagitis(EoE)is an emerging chronic local immune-mediated disease of the *** proton pump inhibitors and food-restrictiondiets swallowed topical corticosteroids(STC)can be offered as a first line therapy according to current *** review describes the background and practical management of STCs in *** far,mainly asthma inhalers containing either budesonide or fluticasone have been administered to the esophagus by swallowing these medications“off label”.Recently esophagus-targeted formulations of topical steroids have been developed showing clinicopathological response rates up to 85%-an orodispersible tablet of budesonide has been approved as the first“in label”medication for EoE in Europe in June *** it was shown that disease remission induction of EoE by STCs is highly effective,there is still a lack of data regarding long-term and maintenance ***,current studies on STC maintenance therapy add some movement into the game.

关键词： Eosinophilic esophagitis Swallowed topical corticosteroids Esophagustargeted formulations of topical steroids Fluticasone Budesonide Budesonide orodispersible tablet Budesonide oral suspension

Molecular biological research on Foraminifera

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Progress in Natural Science:Materials International 2005年第8期15卷 673-677页

作者： Kemal Topac ERTAN,christoph HEMLEBEN Institute and Museum of Geology and Paleontology University of Tuebingen D-72076 Tuebingen Germany Institute and Museum of Geology and Paleontology University of Tuebingen D-72076 Tuebingen Germany

As one of the most important groups in micropaleontology, Foraminifera is traditionally described to have a membranous, agglutinated or carbonate shell according to its morphology, which resembles the marine granuloreticuloseans. However, recent molecular analyses on its ribosomal RNA gene have disclosed the existence of the naked, and also freshwater and terrestrial species. Foraminiferal SSU rDNA sequence suggests that this group is positioned at the base of the Eukaryotes phylogenetic trees, between Euglenoida and Diplomonadida. Existence of a large amount of genetic types in planktonic foraminifera suggests an underestimation of the biodiversity for the nearly 50 species in world oceans and their close relationship with the ocean environment, such as bio-geographic distribution and water currents. This provides a more reliable proxy for future paleoenvironmental study.

关键词： Foraminifera ribosomal DNA molecular biology phylogeny paleoceanography.

Comparison of modelled-and remote sensing-derived daily snow line altitudes at Ulugh Muztagh,northern Tibetan Plateau

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Journal of Mountain Science 2016年第4期13卷 593-613页

作者： Marinka SPIESS Eva HUINTJES christoph SCHNEIDER Department of Geography RWTH Aachen UniversityWiillnerstr.5b52066 AachenGermany Humbold University Berlin Unter den Linden 610099 BerlinGermany

The ice cap Ulugh Muztagh in the central Kunlun Shan at the northern fringe of the Tibetan Plateau is a very isolated region with arid cold conditions. No observational, meteorological or glaciological ground truth data is available. Using the Moderate-resolution Imaging Spectroradiometer(MODIS) Level 1 radiance Swath Data(MOD02QKM) with a spatial resolution of 250 m, transient snow lines during the months of July to September in 2001 to 2014 are derived. Results are used to calibrate the physical based Coupled Snowpack and Ice surface energy and Mass balance model(COSIMA). The model runs on a representative detail region of Ulugh Muztagh(UM) on a digital elevation model with the same spatial resolution as the MODIS bands. In the absence of field observations, the model is driven solely by dynamically downscaled global analysis data from the High Asia Refined analysis(HAR). We compare remote sensing derived and modelled mean regional transient snow line altitudes in the course of consecutive summer seasons in 2008 to 2010. The resulting snow line altitude(SLA) and annual equilibrium line altitude(ELA) proxy of both methods coincide very well in their interannual variability in accordance with interannual variability of climatic conditions. Since SLAs of both methods do notconsistently agree on a daily basis a usage of remote sensing derived SLAs for model calibration in the absence of field observation data is only limitedly feasible for daily analysis. ELA approximation using the highest SLA at the end of ablation period may not be applied to UM because the negative winter mass balance(MB) is not reflected in the summer SLA. The study reveals moderate negative MB for UM throughout the modelling period. The mean regional MB of UM accounts for-523±410 mm w.e. a-1 in the modelling period. Hence UM seems not to belong to the area of the ‘Karakorum anomaly' comprising a region of positive mass balances in recent years which has its centre presumably in the Western Kunlu

关键词： Ulugh Muztagh Imaging spectroradiometer MODIS COSIMA Energy balance Snow line Tibetan Plateau Kunlun Shan

Nano-Morphology of a Polymer Electrolyte Fuel Cell Catalyst Layer Imaging, Reconstruction and Analysis

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Nano Research 2011年第9期4卷 849-860页

作者： Simon Thiele Roland Zengerle christoph Ziegler Laboratory for MEMS Applications Department of Microsystems Engineering--IMTEK University of Freiburg Georges-Koehler-Allee106 79110 Freiburg Germany

The oxygen reduction reaction （ORR） in the cathode catalyst layer （CCL） of polymer electrolyte fuel cells （PEFC） is one of the major causes of performance loss during operation. In addition, the CCL is the most expensive component due to the use of a Pt catalyst. Apart from the ORR itself, the species transport to and from the reactive sites determines the performance of the PEFC. The effective transport properties of the species in the CCL depend on its nanostructure. Therefore a three-dimensional reconstruction of the CCL is required. A series of two-dimensional images was obtained from focused ion beam- scanning electron microscope （FIB-SEM） imaging and a segmentation method for the two-dimensional images has been developed. The pore size distribution （PSD） was calculated for the three-dimensional geometry. The influence of the alignment and the anisotropic pixel size on the PSD has been investigated. Pores were found in the range between 5 nm and 205 nm. Evaluation of the Knudsen number showed that gas transport in the CCL is governed by the transition flow regime. The liquid water transport can be described within continuum hydrodynamics by including suitable slip flow boundary conditions.

关键词： Cathode catalyst layer (CCL), polymer electrolyte fuel cell (PEFC), tomograph three-dimensional reconstruction

Estimation of particle dynamics in 2-D fluidized beds using particle tracking velocimetry

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Particuology 2015年第5期13卷 39-51页

作者： Thomas Hagemeier christoph Roloff Andreas Buck Evangelos Tsotsas NaWiTec Thermal Process EngineeringOtto-von-Guericke University MagdeburgUniversitaetsplatz 239106 MagdeburgGermany Fluid Dynamics and Technical Flow Otto-von-Guericke University MagdeburgUniversitaetsplatz 239106 MagdeburgGermany

The experimental characterization of particle dynamics in fluidized beds is of great importance in fostering an understanding of solid phase motion and its effect on particle properties in granulation processes, Commonly used techniques such as particle image velocimetry rely on the cross-correlation of illumination intensity and averaging procedures. It is not possible to obtain single particle velocities with such techniques. Moreover, the estimated velocities may not accurately represent the local particle velocities in regions with high velocity gradients. Consequently, there is a need for devices and methods that are capable of acquiring individual particle velocities. This paper describes how particle tracking velocimetry can be adapted to dense particulate flows. The approach presented in this paper couples high-speed imaging with an innovative segmentation algorithm for particle detection, and employs the Voronoi method to solve the assignment problem usually encountered in densely seeded fows. Lagrangian particle tracks are obtained as primary information, and these serve as the basis for calculating sophisticated quantities such as the solid-phase flow field, granular temperature, and solid volume fraction. We show that the consistency of individual trajectories is sufficient to recognize collision events.

关键词： Particle dynamics Particle tracking velocimetry Pseudo-2D Fluidized bed

Microcrack Formation During Gas Metal Arc Welding of High-Strength Fine-Grained Structural Steel

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Acta Metallurgica Sinica(English Letters) 2014年第1期27卷 140-148页

作者： christoph Heinze Thomas Michael Andreas Pittner Michael Rethmeier Division 9.3 "Welding Technology" BAM Federal Institute for Materials Research and TestingUnter den Eichen 8712205 BerlinGermany Joining and Coating Technology Fraunhofer-Institute for Production Systems and Design Technology IPKPascalstraβe 8-910587 BerlinGermany

The recent development of high-performance-modified spray arc processes in gas metal arc welding due to modern digital control technology and inverter power sources enables a focused spray arc, which results in higher penetration depths and welding speed. However, rnicrocracks occurred in the weld metal while approaching the process limits of the modified spray arc, represented by a 20-mm double layer DV-groove butt-weld, These cracks were detected in structural steel exhibiting a yield strength level of up to 960 MPa and are neither dependent on the used weld power source nor a consequence of the modified spray arc process itself. The metallographic and fractographic investigations of the rather exceptional fracture surface lead to the classification of the microcracks as hot cracks, The effects of certain welding parameters on the crack probability are clarified using a statistical design of experiment. However, these microcracks do not impact the design specification for toughness in the Charpy V-notch test （absorbed energy at -40 ℃ for the present material is 30 J）.

关键词： High-strength low-alloy steel Welding Fracture Design of experiments Microcracking

Overcoming unintended immunogenicity in immunocompetent mouse models of metastasis:the case of GFP

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Signal Transduction and Targeted Therapy 2022年第4期7卷 949-950页

作者： christoph Schultheiß Mascha Binder Department of Internal Medicine IV Oncology/HematologyMartin-Luther-University Halle-Wittenberg06120 HalleSaaleGermany

The applicability of immune-competent mice to model metastatic tumor progression is limited by the immunogenicity of exogenous proteins like GFP and firefly(ff)luciferase commonly used to track metastatic cells.A recent work published in Cancer Cell by Grzelak and colleagues now shows that development of mouse models that have been centrally tolerized to GFP can overcome this obstacle in transplantation models of metastasis.

关键词： metastasis metastatic immunogenicity

Percutaneous endoscopic gastrostomy—Too often?Too late?Who are the right patients for gastrostomy?

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World Journal of Gastroenterology 2020年第20期26卷 2464-2471页

作者： christoph G Dietrich Konrad Schoppmeyer Dietrich Medical ClinicBethlehem-Gesundheitszentrum Stolberg/Rhld.Stolberg D-52222Germany Medical Clinic Ⅱ Euregio-Klinik NordhornNordhorn D-48529Germany

Percutaneous endoscopic gastrostomy is an established method to provide nutrition to patients with restricted oral uptake of fluids and ***,we review the methods,indications and complications of this *** gastrostomy can be safely and easily performed during gastroscopy,the right patients and timing for this intervention are not always *** in patients with dementia,the indication for and timing of gastrostomies are often *** this patient group,clear data for enteral nutrition are lacking;however,some evidence suggests that patients with advanced dementia do not benefit,whereas patients with mild to moderate dementia might benefit from early enteral ***,other patient groups with temporary or permanent restriction of oral uptake might be a useful target population for early enteral nutrition to maintain mobilization and muscle *** plead for a coordinated study program for these patient groups to identify suitable patients and the best timing for tube implantation.

关键词： Gastrostomy Nutrition Dementia Percutaneous endoscopic gastrostomy Oncologic diseases Endoscopy Neurodegenerative disorders