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Chinese Journal of Polymer Science 2019年第9期37卷 912-918页

作者： Ann-Kathrin Danner Daniel Leibig Lea-Marie Vogt holger Frey Institute of Organic Chemistry Johannes Gutenberg- Universitat Mainz Duesbergweg 10-14 55128 Mainz Germany Graduate School Materials Science in Mainz Staudinger Weg 9 55128 Mainz Germany

The monomer-activated anionic ring-opening copolymerization (AROP) of ethylene oxide (EO) and epichlorohydrin (ECH) using tetraoctylammonium bromide as an initiator and triisobutylaluminum (i-Bu3Al) as an activator was studied. The properties of the copolymers as well as the microstructure have been analyzed in detail via an in situ NMR kinetics study. The statistical copolymers exhibited molecular weights ranging from 2350 g·mol^-1 to 38000 g·mol^-1 (measured by SEC, PEG-standards) and moderate dispersities of 1.27-1.44. The thermal property tests revealed both a glass transition and melting for all copolymers, supporting a block-like nature. Applying in situ NMR kinetic measurements, the reactivity ratios of EO and ECH were determined to be strongly disparate, i.e., rEo = 9.2 and rECH = 0.10. This shows that the simple one-pot statistical anionic copolymerization of EO and ECH via the monomer-activated AROP resulted in the formation of strongly tapered, block-like structures. Furthermore, post-polymerization functionalization of the reactive chloromethyl groups by nucleophilic displacement was investigated for the copolymers. Copolymerization of EO and ECH offers a broad platform for further functionalization and therefore the possibility to prepare a variety of multifunctional PEGs.

关键词： Epichlorohydrin Polymerization Ring-opening Copolymerization Reactivity ratios Epoxide

The potential molecular mechanism of overexpression of uPA, IL-8, MMP-7 and MMP-9 induced by TRAIL in pancreatic cancer cell

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Hepatobiliary & Pancreatic Diseases International 2008年第2期7卷 201-209页

作者： Anna Trauzold Christian Rder holger Kalthoff Molecular Oncology Research Laboratory Clinic for General and Thoracic Surgery Christian-Albrechts-University 24105 Kiel Germany

BACKGROUND: TNF-related apoptosis-inducing ligand (TRAIL) is a death ligand of the TNF-superfamily that has been implicated in inducing apoptosis in some tumor cells. The purpose of this study was to find out if TRAIL could induce the expression of uPA, IL-8, MMP-7 and MMP-9. and to explore the corresponding potential signaling transduction pathway in pancreatic cancer cells. METHODS: Colo357wt, Panc89 and PancTu I cell lines were stimulated by TRAIL (100 ng/ml). Crystal violet cell vitality assay was used to check the sensitivity to TRAIL-induced apoptosis. Real-time RT-PCR tested the expression of uPA, IL-8, MMP-7 and MMP-9. RESULTS: TRAIL can stimulate the expression of uPA, IL-8, MMP-7 and MMP-9 in pancreatic cancer cell lines, especially in Colo357wt. The members of caspases, MEK1/2, PKC, and NF-kappa B are involved in TRAIL-induced expression of uPA, IL-8, MMP-7 and MMP-9. Furthermore, caspases play a different role in Colo357wt, Panc89 and PancTu I. CONCLUSIONS: TRAIL-treatment may result in the enhancement of invasion involving the signaling pathways of caspases, MEK1/2, PKC and NF-kappa B, in pancreatic cancer cells. It points to the necessity to carefully evaluate in vivo side effects of TRAIL.

关键词： TRAIL molecular mechanism pancreatic neoplasms

Trilateral interaction between innervation,leukocyte,and adventitia:a new driver of atherosclerotic plaque formation

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Signal Transduction and Targeted Therapy 2022年第8期7卷 2670-2672页

作者： Yahya Sohrabi holger Reinecke Oliver Soehnlein Department of Cardiology I—Coronary and Peripheral Vascular Disease Heart FailureUniversity Hospital MünsterWestfälische Wilhelms-UniversitätMünsterGermany Institutes of Molecular Genetics of the Czech Academy of Sciences PragueCzechia Institute of Experimental Pathology(ExPat) Center for Molecular Biology of Inflammation(ZMBE)University Hospital MünsterWestfälische Wilhelms-UniversitätMünsterGermany Department of Physiology and Pharmacology(FyFa) Karolinska InstitutetStockholmSweden

A recent study by Mohanta et *** a new understanding of neuroimmune interactions in *** atherosclerotic plaques are not innervated,ablating the sympathetic innervation to these regions attenuated atherosclerosis,suggesting a potential novel therapeutic *** continues to be the leading cause of death in industrialized countries due to its complications such as acute myocardial infarction or *** disease is the result of a complex process,consisting of sub-endothelial lipid retention,immune cell migration,proteolytic injury,altogether leading to a chronic inflammatory responses in the wall of large arteries and ultimately plaque development.2 The inner layer of the blood vessels is not innervated and hence the nervous system connects with the vessel through its most outer layer,the lamina adventitia,hereby controlling important functions including arterial blood *** such homeostatic control of vessel function,increasing evidence demonstrates that activation of the sympathetic nervous system can modulate the degree of arterial inflammation.

关键词： sympathetic acute hence

Weighted LBF for spaceborne general bistatic SAR processing

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Progress in Natural Science:Materials International 2008年第10期18卷 1271-1277页

作者： Otmar Loffeld Robert Wang holger Nies Ul-Ann Qurat The Center for Sensorsystems (ZESS) University of Siege-nPaul-Bonatz-Str.9-11Siegen 57076Germany The Center for Sensorsystems (ZESS) University of SiegenPaul-Bonatz-Str.9-11Siegen 57076Germany

Loffeld’s bistatic formula (LBF) is the first two-dimensional analytic point target reference spectrum derived for general bistatic SAR frequency domain *** phase history is expanded in Taylor series around the individual points of stationary phase of the trans- mitter-target and target-receiver phase histories,respectively,and thus the common bistatic stationary phase point can be obtained using the method of stationary ***,it shows limitations for extreme bistatic configurations,namely the highly squinted mode and space-surface *** weighted LBF (WLBF) is proposed in this paper based on the different contributions of total phase modulation from the transmitter and *** formulae we derived are compared with that of the original *** extreme bistatic stripmap SAR data can be focused using WLBF,which accommodates the spaceborne squint geometry using the modified effec- tive velocity solution.A point target simulation example is presented to verify the accuracy of the new WLBF spectrum.

关键词： Bistatic SAR SAR Weighted LBF (WLBF) Hybrid bistatic configuration Effective velocity approximation

Comparative characterization of two natural humic acids in the Pearl River Basin, China and their environmental implications

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Journal of Environmental Sciences 2010年第11期22卷 1695-1702页

作者： Juan Liu Jin Wang Yongheng Chen holger Lippold Johanna Lippmann-Pipke Key Laboratory of Water Safety and Protection in the Pearl River Delta Ministry of Education Guangzhou University Guangzhou 510006 China. Forschungzentrum Dresden Rossendorf Institute of Radiochemistry Research Site Leipzig Leipzig 04318 Germany

Two humic acids （HAs） were isolated from contaminated river sediments present under comparative conditions in the Pearl River Basin, China. YFHA （the HA extracted at an open pyrite mining area in Yunfu） exhibited a lower absorption intensity for certain bands in the Fourier transform infrared spectra, a lower E 4 /E 6 value （the UV absorbances at 465 nm （E 4 ） and 665 nm （E 6 ））, a lower apparent molecular weight, a lower polarity and a lower oxygen functionality in comparison with GZHA （the HA isolated at an urban living area in Guangzhou）. All these differences indicated a higher degree of humification of YFHA than GZHA. Overall, the enrichment patterns of permanent heavy metals in the studied HAs were similar to those in corresponding sediments. In particular, YFHA exhibited high enrichment of trace element Tl, a characteristic concomitant from the mining of the pyrite minerals. The adsorption isotherms of two HAs for goethite and pyrolusite, two representative geological materials, conformed to the Langmuir equation. Based on the qualitative relationships between the Langmuir constants of the adsorption isotherms and the chemical characteristics of HAs, the main mechanism of HA adsorption on these materials was suggested to be hydrophobic interaction. This study highlighted the promising use of HA as a peculiar bio-indicator of uncommon trace metal contaminations. The HA adsorption mechanism on representative geological materials further provided a theoretical basis for the study on the unusual metal behavior in complex environmental settings.

关键词： humic acid permanent metal load adsorption goethite pyrolusite

Using Climate Factors to Estimate Flood Economic Loss Risk

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International Journal of Disaster Risk Science 2021年第5期12卷 731-744页

作者： Xinjia Hu Ming Wang Kai Liu Daoyi Gong holger Kantz Academy of Disaster Reduction and Emergency Management Beijing Normal UniversityBeijing 100875China School of National Security and Emergency Management Beijing Normal UniversityBeijing 100875China Max-Planck Institute for the Physics of Complex Systems 01187 DresdenGermany

Estimation of economic loss is essential for stakeholders to manage flood *** flooding events are closely related to extreme precipitation,which is influenced by large-scale climate *** the lagged influence of climate factors,we developed a flood-risk assessment framework and used Hunan Province in China as an example to illustrate the risk assessment *** main patterns of precipitation—as a connection between climate factors and flood economic losses—were extracted by the empirical orthogonal function(EOF)*** identified the correlative climate factors through crosscorrelation analysis and established a multiple stepwise linear regression model to forecast future precipitation *** assessment was done based on the main precipitation *** the economic dataset is limited,a Monte Carlo simulation was applied to simulate 1000-year flood loss events under each precipitation regime(rainy,dry,normal years)to obtain aggregate exceedance probability(AEP)and occurrence exceedance probability(OEP)*** found that precipitation has a strong influence on economic loss risk,with the highest risk in rainy *** economic development imbalances are the potential reason for the varying economic loss risks in different regions of Hunan *** the climate indices with at least several months prediction lead time are strong indicators in predicting precipitation,the framework we developed can estimate economic loss risk several months in advance.

关键词： Atmospheric and oceanic variables Flood risk Forecast-based economic loss assessment Hunan Province Risk management

Filtered Backprojection Reconstruction with Depth-Dependent Filtering

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Tsinghua Science and Technology 2010年第1期15卷 17-24页

作者： Frank Dennerlein holger Kunze Frédéric Noo Siemens AG Healthcare SectorForchheim 91301Germany UCAIR Department of RadiologyUniversity of UtahSalt Lake CityUT 84108USA

A direct filtered-backprojection （FBP） reconstruction algorithm is presented for circular cone-beam computed tomography （CB-CT） that allows the filter operation to be applied efficiently with shift-variant band-pass characteristics on the kernel function. Our algorithm is derived from the ramp-filter based FBP method of Feldkamp et al. and obtained by decomposing the ramp filtering into a convolution involving the Hilbert kernel （global operation） and a subsequent differentiation operation （local operation）. The differentiation is implemented as a finite difference of two （Hilbert filtered） data samples and carried out as part of the backprojection step. The spacing between the two samples, which defines the low-pass characteristics of the filter operation, can thus be selected individually for each point in the image volume. We here define the sample spacing to follow the magnification of the divergent-beam geometry and thus obtain a novel, depth-dependent filtering algorithm for circular CB-CT. We evaluate this resulting algorithm using computer-simulated CB data and demonstrate that our algorithm yields results where spatial resolution and image noise are distributed much more uniformly over the field-of-view, compared to Feldkamp＇s approach.

关键词： computed tomography (CT) reconstruction filtered backprojection circular cone-beam CT

Entropy dominated behaviors of confined polymer-nanoparticle composites

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Chinese Physics B 2012年第11期21卷 513-517页

作者：曹学正 Merlitz holger Sommer Jens-Uwe 吴晨旭 Department of Physics and ITPA Xiamen University Leibniz-Institut fr Polymerforschung Dresden

Stretched polymers will lose their possible configurations if they are mixed with nanoparticles or touch a hard wall, which leads to a strong depletion attraction responsible for the enrichment of nanoparticles near substrates. Moreover, it is found that there exists a sacrifice mechanism in confined pure polymer samples or polymer-nanoparticle mixtures, that part of the polymers, in order to reach a minimum free energy for the total system, are adsorbed on hard walls even though they lose their conformation. The current study provides a simple yet effective approach for the design of thin polymer composites.

关键词： conformation entropy nanoparticle depletion attraction thin polymer layer

An Algebraic Detection Approach for Control Systems under Multiple Stochastic Cyber-attacks

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IEEE/CAA Journal of Automatica Sinica 2015年第3期2卷 258-266页

作者： Yumei Li holger Voos Mohamed Darouach Changchun Hua the Interdisciplinary Centre for Security Reliability and Trust(SnT) University of Luxembourg the Centre de la Recherche en Automatique de Nancy(CRAN) Universite de Lorraine the Institute of Electrical Engineering Yanshan University

In order to compromise a target control system successfully, hackers possibly attempt to launch multiple cyberattacks aiming at multiple communication channels of the control system. However, the problem of detecting multiple cyber-attacks has been hardly investigated so far. Therefore, this paper deals with the detection of multiple stochastic cyber-attacks aiming at multiple communication channels of a control system. Our goal is to design a detector for the control system under multiple cyberattacks. Based on frequency-domain transformation technique and auxiliary detection tools, an algebraic detection approach is proposed. By applying the presented approach, residual information caused by different attacks is obtained respectively and anomalies in the control system are detected. Sufficient and necessary conditions guaranteeing the detectability of the multiple stochastic cyber-attacks are obtained. The presented detection approach is simple and straightforward. Finally, two simulation examples are provided, and the simulation results show that the detection approach is effective and feasible. © 2014 Chinese Association of Automation.

关键词： Algebra Communication channels (information theory) Control systems Crime Frequency domain analysis Personal computing Stochastic systems

Transport Modelling for EAST with LHRF and NBI

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Plasma Science and Technology 2009年第4期11卷 417-421页

作者：周登 holger St.JOHN 胡业民李国强任启龙欧靖 Institute of Plasma Physics Chinese Academy of Sciences Centre for Magnetic Fusion Theory Chinese Academy of Sciences General Atomics

Lower hybrid simulation code （LSC） is integrated into transport code ONETWO to model discharges of EAST with heating and current drive using both lower hybrid wave and neutral beam injection. To test the integration, the current profiles driven by both lower hybrid wave and neutral beam injection are presented for a given equilibrium and sample density and temperature profiles before carrying out a time advancing simulation. For a steady state H-mode discharge, the temperature profiles are evolved using GLF23 transport model with a boundary value specified at the normalized minor radius pN = 0.9. A case of steady state with non-inductively driven current accounting for up to 80% is presented.

关键词： ONETWO LSC EAST modeling