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Epithelial restitution and wound healing in inflammatory bowel disease

World Journal of Gastroenterology 2008年第3期14卷 348-353页

作者： andreas Sturm Axel U Dignass Department of Gastroenterology and hepatology Charité-Campus Virchow Clinic Berlin Germany Department of Gastroenterology Hepatology Oncology and Metabolic Diseases Markus-Krankenhaus Frankfurt/Main Germany

Inflammatory bowel disease is characterized by a chronic inflammation of the intestinal mucosa. The mucosal epithelium of the alimentary tract constitutes a key element of the mucosal barrier to a broad spectrum of deleterious substances present within the intestinal lumen including bacterial microorganisms, various dietary factors, gastrointestinal secretory products and drugs. In addition, this mucosal barrier can be disturbed in the course of various intestinal disorders including inflammatory bowel diseases. Fortunately, the integrity of the gastrointestinal surface epithelium is rapidly reestablished even after extensive destruction. Rapid resealing of the epithelial barrier following injuries is accomplished by a process termed epithelial restitution, followed by more delayed mechanisms of epithelial wound healing including increased epithelial cell proliferation and epithelial cell differentiation. Restitution of the intestinal surface epithelium is modulated by a range of highly divergent factors among them a broad spectrum of structurally distinct regulatory peptides, variously described as growth factors or cytokines. Several regulatory peptide factors act from the basolateral site of the epithelial surface and enhance epithelial cell restitution through TGF-13-dependent pathways. In contrast, members of the trefoil factor family （TFF peptides） appear to stimulate epithelial restitution in conjunction with mucin glycoproteins through a TGF-13-independent mechanism from the apical site of the intestinal epithelium. In addition, a number of other peptide molecules like extracellular matrix factors and blood clotting factors and also non- peptide molecules including phospholipids~ short-chain fatty acids （SCFA）, adenine nucleotides, trace elements and pharmacological agents modulate intestinal epithelial repair mechanisms. Repeated damage and injury of the intestinal surface are key features of various intestinal disorders including inflammatory bowel disease

关键词： Intestines Wound healing Inflammation Restitution

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The break-up tendency of long rod projectiles

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Defence Technology（防务技术） 2016年第2期12卷 177-187页

作者： Ewa LIDéN andreas hELTE FOI Swedish Defence Research Agency

A model for the tendency of fragmentation of a long rod projectile subjected to armour components in add-on armours such as reactive armour and active protection systems is presented. The model is based on studies of the interaction between a cylindrical streamlined projectile and moving thin plates(backwards moving like the front plate in a reactive armour panel and forwards moving like the rear plate in a reactive armour panel).The assumption behind the model is that the sliding force, with velocity vslidebetween the projectile and the plate, gives rise to a transverse velocity vtransof the projectile segment it passes, which will deflect the projectile segment. This deflection is assumed to be a major reason for the fractures that can emerge along the projectile. The velocity, geometry and material of the projectile and the plate are of importance for the fragmentation of the projectile and the dimensionless parameterδ? = v trans vslideexpresses how these parameters influence the break-up tendency. Experiments and simulations have verified that the identifiedδ?-parameter predicts an increased amount of fragmentation of the projectile with increasing value of this parameter.

关键词：长杆弹破裂反应装甲趋势模型主动防护系统横向速度无量纲参数附加装甲

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On a Strategy to Develop Robust and Simple Tariffs from Motor Vehicle Insurance Data

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Acta Mathematicae Applicatae Sinica 2005年第2期21卷 193-208页

作者： andreas Christmann Department of Statistics University of Dortmund D-44221 Dortmund Germany

Abstract The goals of this paper are twofold: we describe common features in data sets from motor vehicle insurance companies and we investigate a general strategy which exploits the knowledge of such features. The results of the strategy are a basis to develop insurance tariffs. We use a nonparametric approach based on a combination of kernel logistic regression and e-support vector regression which both have good robustness properties. The strategy is applied to a data set from motor vehicle insurance companies.

关键词： Data mining kernel logistic regression robustness statistical machine learning support vector regression

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Signaling pathways involved in the inhibition of epidermal growth factor receptor by erlotinib in hepatocellular cancer

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World Journal of Gastroenterology 2006年第32期12卷 5160-5167页

作者： Alexander huether Michael hpfner andreas P Sutter Viola Baradari Detlef Schuppan hans Scherübl Charité-Universittsmedizin Berlin Campus Benjamin Franklin Medical Clinic ⅠGastroenterology/Infectious Diseases/RheumatologyBerlinGermany harvard Medical School Beth Israel Deaconess Medical Center Division of Gastroenterology and HepatologyBostonUnited States

AIM： To examine the underlying mechanisms of erlotinib-induced growth inhibition in hepatocellular carcinoma （hCC）. METhODS： Erlotinib-induced alterations in gene expression were evaluated using cDNA array technology; changes in protein expression and/or protein activation due to erlotinib treatment as well as IGF-1-induced EGFR transactivation were investigated using Western blotting. RESULTS： Erlotinib treatment inhibited the mitogen activated protein （MAP）-kinase pathway and signal transducer of activation and transcription （STAT）- mediated signaling which led to an altered expression of apoptosis and cell cycle regulating genes as demonstrated by cDNA array technology. Overexpression of proapoptotic factors like caspases and gadds associated with a down-regulation of antiapoptotic factors like Bcl-2, Bcl-XL or jun D accounted for erlotinib＇s potency to induce apoptosis. Downregulation of cell cycle regulators promoting the G1/S-transition and overexpression of cyclin-dependent kinase inhibitors and gadds contributed to the induction of a G1/G0-arrest in response to erlotinib. Furthermore, we displayed the transactivation of EGFR-mediated signaling by the IGF-1-receptor and showed erlotinib＇s inhibitory effects on the receptor-receptor cross talk. CONCLUSION： Our study sheds light on the understanding of the mechanisms of action of EGFR-TK- inhibition in hCC-cells and thus might facilitate the design of combination therapies that act additively or synergistically. Moreover, our data on the pathways responding to erlotinib treatment could be helpful in predicting the responsiveness of tumors to EGFR-TKIs in the future.

关键词： Epidermal growth factor receptor Insulinlike growth factor receptor Tarceva^TM Signal transducerof activation and transcription Extracellular regulatedkinase Gene expression

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Autonomous vehicles wheel wander: Structural impact on flexible pavements

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第3期8卷 388-398页

作者： Konstantina Georgouli Christina Plati andreas Loizos Department of Transportation Planning and Engineering School of Civil EngineeringNational Technical University of AthensZografou 15773Greece

Autonomous vehicles(AVs), including trucks, are already available and their adoption is coming at a rapid pace. Despite the fact that this new transportation technology will travel on existing pavement infrastructure assets, the study and investigation of the AVs structural impact on pavements has not reached the same level of attention and maturity as other related research areas. Considering the extensive investment on pavement construction and maintenance, the necessity to fully understand these impacts in the long term, is becoming evident. The present paper presents and discusses currently published relevant research and findings on the quantification of the wheel wander potential impact,both negative and positive, offering potential insightful future areas of enquiry to help mold and shape future research for this emerging field. The paper focuses on the impact of the AVs zero lateral wheel wander on both new flexible pavement design and the damage accumulation within existing flexible pavement structures. Other wheel wander distributions(normal, uniform, etc.) are investigated as well. The outcome and findings are that the AVs zero lateral wheel wander has a definable negative structural impact on flexible pavement structures in comparison to current human-driven(non-autonomous) vehicles that tend to follow a normal lateral wheel wander distribution. however, under certain defined conditions(optimal wheel wander distribution), the pavement service life can be potentially extended.

关键词： Road engineering Autonomous vehicles Wheel wander Pavement design Pavement performance

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Stop-and-go waves induced by correlated noise in pedestrian models without inertia

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第1期7卷 52-60页

作者： Antoine Tordeux andreas Schadschneider Sylvain Lassarre School of Mechanical Engineering and Safety Engineering University of WuppertalWuppertal 42119Germany Institute for Theoretical Physics University of CologneCologne 50937Germany Engineering of Surface Transportation Networks and Advanced Computing Laboratory French Institute of Science and Technology for TransportDevelopment and NetworksMarne La Vallee E-77447France

Stop-and-go waves are commonly observed in traffic and pedestrian *** most microscopic traffic models,they occur through a phase transition and instability of the homogeneous solution after fine tuning of *** effects are believed to play an important role in this *** this article,we present a novel explanation for stop-and-go waves based on stochastic effects in the absence of *** model used is a first order optimal velocity(OV)model including an additive stochastic noise.A power spectral analysis for single-file pedestrian trajectories highlights the existence of Brownian speed *** use the Ornstein-Uhlenbeck process to describe such a correlated *** introduction of this specific colored noise in the first order OV model allows describing realistic stop-and-go behavior without requiring instabilities or phase transitions,the homogeneous configurations being systematically stochastically *** compare the stochastic model to deterministic unstable OV models and analyze individual speed autocorrelation to describe the nature of the waves in stationary *** apply the approach to pedestrian single-file motion and compare simulation results to real pedestrian *** simulation results are quantitatively very similar to the real *** discuss plausible values for the model parameters and their meaning.

关键词： Transportation engineering Pedestrian single-file motion Stop-and-go dynamics First order microscopic model Brownian noise Simulation

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Between plaza and peak: a montological perspective on verticality and urbanization in highland Peru

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Journal of Mountain Science 2023年第10期20卷 2783-2803页

作者： andreas hALLER Domenico BRANCA Deyvis CANO Institute for Interdisciplinary Mountain Research Austrian Academy of SciencesInnsbruck 6020Austria Department of humanities and Social Sciences University of SassariSassari 07100Italy Programa Académico de Ingeniería Ambiental Universidad de HuánucoHudnuco 10001Peru

Under the influence of concentrated and extended urbanization,Andean cities and the different altitudinal zones of their“hinterlands”are experiencing profound changes in land cover—from the central plazas up to the highest *** complex regional-geographic characteristics of these socioecological systems,such as the vertical complementarity of land use,require a montological perspective on verticality and urbanization:it transcends disciplinary approaches and can be crucial to properly interpret the trajectories of land cover change and formulate hypotheses for future practiceoriented *** trajectories of land cover change characterized altitudinal zones of Andean cities and their surroundings over the last three decades?Are there similarities that allow for the formulation of more general hypotheses?Using the Peruvian cases of Cusco and huaraz,and combining a traditional altitudinal zonation model of land use in Peru with direct field observations and GIS-based analyses of remotely sensed data from 1991,2001,2011,and 2021,this study identifies the main trajectories of land cover change in the Quechua(>2300–3500 m),Suni(>3500–4000 m),and Puna(>4000–4800 m)regions—and finds insightful similarities between Cusco and huaraz:(1)an impressive area of built-up land substitutes grassland in the Quechua,which,following regional altitudinal zonation models,is characterized by irrigated and rain-fed cropland;(2)an unexpected expansion of irrigated cropland takes place in the Suni,which,in theory,often lacks irrigation infrastructure and is mostly used for rain-fed tuber cultivation;and(3)a clear change from“other land”to grassland occurs in the Puna—where grassland is thought to predominate,anyway,since pre-hispanic *** that these changes reflect the interplay between speculative fallow,agricultural intensification,and ecological restoration,the results can be read as vertically complementary,local manifestations of concentrated and extended urba

关键词： Mountain cities Mountain agriculture Land use change Land cover change Rural-urban linkages Montology

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Extending the operational lifetimes of all-direct electron transfer enzymatic biofuel cells by magnetically assembling and exchanging the active biocatalyst layers on stationary electrodes

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Nano Research 2019年第4期12卷 767-775页

作者： Katharina herkendell andreas Stemmer Ran Tel-Vered Saumerstrasse 4 Nanotechnology Group D-MAVT ETH Zurich Ruschlikon CH-8803 Switzerland

Enzymatic biofuel cells promise green power generation from a variety of natural resources, yet these systems all suffer from time-dependent degradati on effects, in particular progress! ng inactivation of enzymes, which severely limit the operati on al lifetimes of such power sources. To extend operational lifetimes, we introduce a method to magnetically exchange exhausted enzymes for fresh ones. To this end, anodic and cathodic enzymes or enzyme cascades are immobilized on carbon coated magnetic nanoparticles. Under the action of suitable magnetic field gradie nts, these nano particles are assembled on the respective stati onary electrodes, or released from the electrodes for collection and subsequent excha nge. We dem on strate this method on a fructose/oxygen con suming biofuel cell emplo ying fructose dehydroge nase and bilirubin oxidase as well as on anodic and cathodic cascades employing fructose dehydrogenase/invertase and bilirubin oxidase/catalase, respectively. The en zyme-modified nan oparticles support direct electro n transfer bioelectrocatalytic curre nts by wiring the redox active cofactors to the carbonaceous coating and from there to the electrode surfaces. The facile injection, assembly, and removal of enzyme-modified magnetic nan oparticles along with fuel solutio n provides a promisi ng approach to exte nd the operati on al lifetime of enzymatic biofuel cells without the need for exchanging entire systems including chambers and electrodes.

关键词： direct electron transfer magnetic nanoparticle enzymatic biofuel cell recharge lifetime enzyme cascade

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Microstructure and physical properties of steel-ladle purging plug refractory materials

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International Journal of Minerals,Metallurgy and Materials 2017年第2期24卷 186-193页

作者： Bin Long Gui-ying Xu Buhr andreas School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Almatis Qingdao Co. Ltd. Qingdao 266071 China Almatis Gmbh Frankfurt 60528 Germany

Three different castables were prepared as steel-ladle purging-plug refractory materials： corundum-based low-cement castable （C-LCC）, corundum-spinel-based low-cement castable （C-S-LCC）, and no-cement corundum-spinel castable （C-S-NCC）（hydratable alu- mina p-A1203 bonded）. The properties of these castables were characterized with regard to water demand/flow ability, cold crushing strength （CCS）, cold modulus of rupture （CMoR）, permanent linear change （PLC）, apparent porosity, and hot modulus of rupture （hMoR）. The re- sults show the CCS/CMoR and hMoR of C-LCC and C-S-LCC are greater than those of the castable C-S-NCC. According to the micro- structure analysis, the sintering effect and the bonding type of the matrix material differ among the three castables. The calcium hexaluminate （CA6） phase in the matrix of C-LCC enhances the cold and hot mechanical strengths. In the case of C-S-LCC, the CA6 and 2CaO·2MgO·14A12O3（C2MEA14） ternary phases generated from the matrix can greatly increase the cold and hot mechanical strengths. In the case of the no-cement castable, sintering becomes difficult, resulting in a lower mechanical strength.

关键词： refractory materials purging plugs castable physical properties microstructure

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Study of borohydride ionic liquids as hydrogen storage materials

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Journal of Energy Chemistry 2019年第6期28卷 17-21页

作者： Loris Lombardo heena Yang andreas Züttel Institute of Chemical Sciences and Engineering (ISIC) Basic Science Faculty (SB) école polytechnique fédérale de Lausanne (EPFL) Valais/WallisEnergypolisRue de I'lndustrie 17CH-1951 SionSwitzerland Empa Materials Science and Technology DiibendorfSwitzerland

Stability of borohydrides is determined by the localization of the negative charge on the boron *** liquids(ILs) allow to modify the stability of the borohydrides and promote new dehydrogenation pathways with a lower activation energy. The combination of borohydride and IL is very easy to realize and no expensive rare earth metals are required. The composite of the ILs with complex hydrides decreases the enthalpy and activation energy for the hydrogen desorption. The Coulomb interaction between borohydride and IL leads to a destabilization of the materials with a significantly lower enthalpy for hydrogen desorption. here, we report a simple ion exchange reaction using various ILs, such as vinylbenzyltrimethylammonium chloride([VBTMA][Cl]), 1-butyl-3-methylimidazolium chloride([bmim][Cl]), and 1-ethyl-1-methylpyrrolidinium bromide([EMPY][Br]) with NaBh4 to decrease the hydrogen desorption temperature. Dehydrogenation of 1-butyl-3-methylimidazolium borohydride([bmim][Bh4]) starts below 100℃. The quantity of desorbed hydrogen ranges between 2.4 wt% and 2.9 wt%, which is close to the theoretical content of hydrogen. The improvement in dehydrogenation is due to the strong amine cation that destabilizes borohydride by charge transfer.

关键词： hydrogen storage Ionic liquid Sodium borohydride Thermolysis

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