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The Influence of High Temperature Exposure on the Wear Performance of a Ni Based Alloy PTA Coating

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材料热处理学报 2004年第5期25卷 152-156页

作者： Karin graf Ana Sofia C.m. d'OIiveira mechanical Department of Universidade Federal do Parana Curitiba BrazilMechanical Department of Universidade Federal do Parana Curitiba Brazil

Degradation phenomena like wear and corrosion, may have their effects accelerated as components operate at high temperature. The aim of this work is to make an indirect evaluation of the influence of high temperature exposure on wear behavior of Ni coatings. A Ni-Cr-mo-W alloy, was deposited with Plasma Transferred Arc (PTA) process. An indirect approach based on the Ahrrenius relationship was used to evaluated long time exposures at high temperatures. To simulate longer exposures at lower temperatures, coatings were exposed to higher temperatures for the same time interval. So coatings were soaked in an air furnace at 650°C, 1000°C and 1200°C. metal/metal wear behavior was evaluated by pin-on-disc tests. Pins were removed from the coatings by eletrodischarge machining and rubbed against a VC31 quenched and tempered tool steel. Two sets of wear tests were run at 2m/s, for different loads (0.5, 1.0, 2.0 and 3.0Kg) and for different sliding distances (120, 720, 1080, 1440 and 1800m).Coatings characterization was done by scanning electronic microscopy and Vickers microhardness. Results showed as temperature is increased, coatings wear performance is altered, and this is associated with microstructural changes.

关键词：磨损 Ni合金 PTA 高温曝露

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Reduced expression ofβ-catenin inhibitor Chibby in colon carcinoma cell lines

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World Journal of Gastroenterology 2006年第10期12卷 1529-1535页

作者： marion m Schuierer Elisabeth graf Ken-Ichi Takemaru Wolfgang Dietmaier Anja-Katrin Bosserhoff Institute of Pathology University of Regensburg Franz-Josef-Strauss-Alice 1193053 RegensburgGermany Department of Pharmacology BST 7-168 Stony BrookNY 11794-8651United States Institute of Pathology University of Regensburg Franz-Josef-Strauss-Allee 1193053 RegensburgGermany

AIm： To analyse the Chibby expression and its function in colon carcinoma cell lines and colorectal carcinoma （CRC）. mETHODS： Chibby expression levels were investigated by quantitative RT-PCR in a panel of seven different colon carcinoma cell lines. By sequencing, we analysed mutational status of Chibby. To test whether Chibby exhibited effects on β-catenin signalling in colon carcinoma cells, we transfected SW480 cells with Chibby expression plasmid and, subsequently, analysed activity of β-catenin and tested for alterations in cellular phenotype. In addition, we examined Chibby mRNA levels in samples of colorectal carcinomas and adjacent normal tissues by using quantitative RT-PCR and hybridised gene chips with samples from CRC and normal tissues. RESULTS： Chibby mRNA expression was strongly downregulated in colon carcinoma cell lines in comparison to normal colon epithelial cells and no mutation in any of the examined colon carcinoma cell lines was found. Further, we could show that Chibby inhibited β-catenin activity in TOPflash assays when over-expressed in SW480 cells. Proliferation and invasion assays with Chibby transfected SW480 cells did not reveal profound differences compared to control cells. In contrast to these in vitro data, quantitative RT-PCR analyses of Chibby mRNA levels in CRC tumor samples did not show significant differences to specimens in adjacent non-cancerous tissue. Consistent with these findings, gene chips analysing tissue samples of tumors and corresponding normal tissue did not show altered Chibby expressionCONCLUSION： Altered Chibby expression might be observed in vitro in different colon carcinoma cell lines. However, this finding could not be confirmed in vitro in CRC tumors, indicating that Chibby is not likely to promote CRC tumor development or progression. As Chibby is an important inhibitor of β-catenin signalling, our data implicate that the usability of colon carcinoma cell lines for in vitro studies analysing the Wnt/β-ca

关键词： Chibby Wnt β-catenin Colorectal carcinoma Colon carcinoma cell lines

5-Azacytidine induces changes in electrophysiological properties of human mesenchymal stem cells

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Cell Research 2006年第12期16卷 949-960页

作者： Bartosz Balana Cecilia Nicolett Ihor Zahanich Eva m.graf Torsten Christ Sabine Boxberger Department of Pharmacology and Toxicology medical Clinic I Medical FacultyDresden University of TechnologyFetscherstr.74D-01307 DresdenGermany

Previously,mouse bone marrow-derived stem cells（mSC）treated with the unspecific DNA methyltransferase inhibi-tor 5-azacytidine were reported to differentiate into *** aim of the present study was to investigate theefficiency of a similar differentiation strategy in human mononuclear cells obtained from healthy bone marrow *** 1-3 passages,cultures were exposed for 24 h to 5-azacytidine（3μm）followed by 6 weeks of further *** treatment did not induce expression of myogenic marker myoD or cardiac markers Nkx2.5 and GATA-4 and didnot yield beating cells during *** patch clamp experiments,approximately 10-15% of treated and untreatedcells exhibited L-type Ca2+ *** all cells showed outwardly rectifying K+currents of rapid or slow *** current amplitude at +60 mV doubled after 6 weeks of treatment compared with time-matched *** capacitance of treated cells was significantly larger than in controls 2 weeks after treatment and remained highafter 6 *** levels ofmRNAs for the K+channels Kv1.1,Kv1.5,Kv2.1,Kv4.3 and KCNmA1 and for theCa2+ channel Cav1.2 were not affected by *** with potassium channel blockers tetraethylammoniumand clofilium at concentrations shown previously to inhibit rapid or slowly activating K+currents of hmSC inhibitedproliferation of these *** results suggest that despite the absence of differentiation of hmSC into cardiomyocytes,treatment with 5-azacytidine caused profound changes in current density.

关键词： human mesenchymal stem cells 5-azacytidine cardiac differentiation outward K~+ currents

Loss of LAT1 sex-dependently delays recovery after caerulein-induced acute pancreatitis

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World Journal of Gastroenterology 2022年第10期28卷 1024-1054页

作者： Cristina m Hagen Eva Roth Theresia Reding graf François Verrey Rolf graf Anurag Gupta Giovanni Pellegrini Nadège Poncet Simone mafalda Rodrigues Camargo Institute of Physiology University of ZurichZurich 8057ZHSwitzerland Swiss Hepato-Pancreato-Biliary Center Department of Visceral and Transplantation SurgeryZurich University HospitalZurich 8091ZHSwitzerland Institute of Veterinary Pathology University of ZurichZurich 8057ZHSwitzerland

BACKGROUND The expression of amino acid transporters is known to vary during acute pancreatitis(AP)except for LAT1(slc7a5),the expression of which remains ***1 supports cell growth by importing leucine and thereby stimulates mammalian target of rapamycin(mTOR)activity,a phenomenon often observed in cancer *** mechanisms by which LAT1 influences physiological and pathophysiological processes and affects disease progression in the pancreas are not yet *** To evaluate the role of LAT1 in the development of and recovery from *** AP was induced with caerulein(cae)injections in female and male mice expressing LAT1 or after its knockout(LAT1 Cre/LoxP).The development of the initial AP injury and its recovery were followed for seven days after cae injections by daily measuring body weight,assessing microscopical tissue architecture,mRNA and protein expression,protein synthesis,and enzyme activity levels,as well as by testing the recruitment of immune cells by FACS and *** The initial injury,evaluated by measurements of plasma amylase,lipase,and trypsin activity,as well as the gene expression of dedifferentiation markers,did not differ between the ***,early metabolic adaptations that support regeneration at later stages were blunted in LAT1 knockout *** in females,we observed less mTOR reactivation and dysfunctional *** later regeneration phase was clearly delayed in female LAT1 knockout mice,which did not regain normal expression of the pancreas-specific differentiation markers recombining binding protein suppressor of hairless-like protein(rbpjl)and basic helixloop-helix family member A15(mist1).Amylase mRNA and protein levels remained lower,and,strikingly,female LAT1 knockout mice presented signs of fibrosis lasting until day *** contrast,pancreas morphology had returned to normal in wild-type *** LAT1 supports the regeneration of acinar cells after *** mice lacking LAT1 exh

关键词： Acute pancreatitis Amino acid transporter LAT1 metabolism Regeneration Fibrosis

Data mining and machine Learning methods Applied to A Numerical Clinching model

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Computer modeling in Engineering & Sciences 2018年第12期117卷 387-423页

作者： marco Gotz Ferenc Leichsenring Thomas Kropp Peter müller Tobias Falk Wolfgang graf michael Kaliske Welf-Guntram Drossel Institute for Structural Analysis Technische UniversitatDresdenGermany Fraunhofer Institute for machine Tools and Forming Technology DresdenGermany

Numerical mechanical models used for design of structures and processes are very complex and high-dimensionally *** understanding of the model characteristics is of interest for engineering tasks and subsequently for an efficient *** analysis methods are known and available to gain insight into existing *** this contribution,selected methods from various fields are applied to a real world mechanical engineering example of a currently developed clinching *** selection of introduced methods comprises techniques of machine learning and data mining,in which the utilization is aiming at a decreased numerical *** methods of choice are basically discussed and references are given as well as challenges in the context of meta-modelling and sensitivities are *** incremental knowledge gain is provided by a step-bystep application of the numerical methods,whereas resulting consequences for further applications are ***,a visualisation method aiming at an easy design guideline is *** visual decision maps incorporate the uncertainty coming from the reduction of dimensionality and can be applied in early stage of design.

关键词： Design data mining computational intelligence meta-modelling permissible design space sensitivity analysis self-organizing maps inverse problem early stage of design clinching

mortality and Long-Term Outcome of Neonates with Congenital Heart Disease and Acute Perinatal Stroke:A Population-Based Case-Control Study

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Congenital Heart Disease 2022年第4期17卷 447-461页

作者： Eszter Vojcek VAnna Gyarmathy Rozsa graf Anna m.Laszlo Laszlo Ablonczy Zsolt Prodan Istvan Seri First Department of Pediatrics Semmelweis UniversityMTA Centre of ExcellenceBudapestHungary Department of Pediatrics Saint John Hospital and North-Buda Unified HospitalsBudapestHungary Epiconsult Biomedical Consulting and medical Communications Agency DoverUSA Department of Epidemiology Johns Hopkins UniversityBaltimoreUSA Department of Rehabilitation Saint John Hospital and North-Buda Unified HospitalsBudapestHungary Institute of mathematics and Base Sciences Hungarian University of Agriculture and Life SciencesGödöllőHungary Gottsegen National Cardiovascular Center BudapestHungary Children’s Hospital Los Angeles University of Southern CaliforniaLos AngelesUSA

Objective:Neonates with congenital heart disease(CHD)and perinatal stroke have high mortality and survivors are at risk for poor long-term neurodevelopmental *** aim of this study was to assess the risk factors and outcome of neonates with both CHD and mRI-confirmed perinatal stroke(Study Group)and compare those to the risk factors and outcome of infants matched for CHD without stroke(Control-1)and of infants matched for mRI-confirmed stroke without CHD(Control-2).methods:We conducted a population-based case-control study enrolling 28 term neonates with CHD and mRI-confirmed acute perinatal stroke born between 2007–2017 in the Central-Hungarian *** of the control groups included 56 *** Bayley Scales of Infant Development-II,the Brunet-Lézine test and the Binet Intelligence scales-V were used for neurodevelopmental follow-up at a median age of 61 ***:mortality was highest in the Study Group(25%compared to 5%and 2%,respectively,p=0.001).Adverse neurodevelopmental outcome was prevalent in the Study(53%)and Control-2 Groups(52%,p=0.03).Significantly different parameters among the three groups included Apgar scores,mode of delivery,gestational age at birth,cardiac interventions and twin *** a multivariable regression analysis adjusted for clinically relevant parameters,patients in the Study Group had significantly higher odds for mortality compared to patients in the Control-1 Group(OR:6.595%CI:1.1–39.4).Conclusions:Neonates with perinatal stroke and CHD are at a higher risk for dying compared to neonates with CHD without *** addition,the stroke-associated direct insult to the brain likely plays an important role in the development of neurodevelopmental morbidity in these patients.

关键词： Congenital heart disease perinatal stroke neurodevelopmental outcome mortality

SCOUR DEPTH AND FLOW PATTERN OF ERODING PLANE JETS

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International Journal of Sediment Research 2004年第1期19卷 15-27页

作者： A.KURNIAWAN,m.S.ALTINAKAR,W.H.graf Switzerland presently Prof. NCCHE University of mississippi USA Prof. LRH Ecole Polytechnique Federale Lausanne Switzerland Res. Assist. LRH Ecole Polytechnique Federale Lausanne Switzerland Res. Assoc. LRH Ecole Polytechnique Federate Lausanne

Local scour may occur when a hydraulic structure is positioned in a channel with an erodible bed. Herewith investigated experimentally are the erosion and flow pattern due to a water jet passing over a channel bed at the asymptotic (final) state. The development of the scour hole, its maximum scour depth and length, are recorded and compared with available scour-depth relations. Two sets of experiments (see Table 1) were carried out. Set 1 (3 runs) was concerned with measuring the vertical instantaneous velocity distribution in the scour hole. The scour hole at the asymptotic (final) state, t = 100 [h] was investigated. Set 2 (5 runs) was concerned with studying the physics of scouring. The scour hole at about mid-state, t = 0.5 [h], was investigated; subsequently the scour-hole depth was linearly extended on the semi-log scale to 72 [h]; no velocity measurements were performed. The present data are put in context with some (popular) existing relations; recommended is a modification of some of these rel

关键词： Local scour Eroding jet Scour depth Flow pattern

Bifunctional chimeric SuperCD suicide gene -YCD: YUPRT fusion is highly effective in a rat hepatoma model

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World Journal of Gastroenterology 2005年第44期11卷 6910-6919页

作者： Florian Graepler marie-Luise Lemken Wolfgang A Wybranietz Ulrike Schmidt Irina Smirnow Christine D GroB martin Spiegel Andrea Schenk Schenk Hansj(o|¨)rg graf Ulrike A Lauer Reinhard Vonthein michael Gregor Sorin Armeanu michael Bitzer Ulrich m.Lauer Department of Internal medicine Ⅰ Section of Experimental Radiology Department of medical Biometry

AIm： To investigate the effects of catalytically superior gene-directed enzyme prodrug therapy systems on a rat hepatoma model. mETHODS： To increase hepatoma cell chemosensitivity for the prodrug 5-fluorocytosine （5-FC）, we generated a chimeric bifunctional SuperCD suicide gene, a fusion of the yeast cytosine deaminase （YCD） and the yeast uracil phosphoribosyltransferase （YUPRT） gene. RESULTS： In vitro stably transduced morris rat hepatoma cells （mH） expressing the bifunctional SuperCD suicide gene （mH SuperCD） showed a clearly marked enhancement in cell killing when incubated with 5-FC as compared with mH cells stably expressing YCD solely （mH YCD） or the cytosine deaminase gene of bacterial origin （mH BCD）, respectively. In vivo, mH SuperCD tumors implanted both subcutaneously as well as orthotopically into the livers of syngeneic ACI rats demonstrated significant tumor regressions （P〈0.01） under both high dose as well as low dose systemic 5-FC application, whereas mH tumors without transgene expression （mH naive） showed rapid progression. For the first time, an order of in vivo suicide gene effectiveness （SuperCD〉〉 YCD〉〉BCD〉〉〉negative control） was defined as a result of a direct in vivo comparison of all three suicide genes. CONCLUSION： Bifunctional SuperCD suicide gene expression is highly effective in a rat hepatoma model, thereby significantly improving both the therapeutic index and the efficacy of hepatocellular carcinoma killing by fluorocytosine.

关键词： YCD/YUPRT fusion Cytosine deaminase GDEPT Suicide gene therapy Hepatoma therapy

The conditional mitochondrial protein complexome in the Arabidopsis thaliana root and shoot

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Plant Communications 2023年第5期4卷 172-190页

作者： Youjun Zhang Silvia martinez Jaime mustafa Bulut Alexander graf Alisdair R.Fernie Center of Plant Systems Biology and Biotechnology 4000 PlovdivBulgaria max-Planck-Institut f€ur molekulare Pflanzenphysiologie Am Muhlenberg 114476 Potsdam-GolmGermany

Protein complexes are important for almost all biological ***,to fully understand how cells work,it is also necessary to characterize protein complexes and their dynamics in response to various cellular ***,the dynamics of protein interaction play crucial roles in regulating the(dis)association of protein complexes and,in turn,regulating biological processes such as ***,mitochondrial protein complexes were investigated by blue native PAGE and size-exclusion chromatography under conditions of oxidative stress in order to monitor their dynamic(dis)*** of enzyme interactions and changes in protein complex abundance were observed in response to oxidative stress induced by menadione *** included changes in enzymatic protein complexes involving g-amino butyric acid transaminase(GABA-T),D-ornithine aminotransferase(D-OAT),or proline dehydrogenase 1(POX1)that are expected to affect proline *** treatment also affected interactions between several enzymes of the tricarboxylic acid(TCA)cycle and the abundance of complexes of the oxidative phosphorylation *** addition,we compared the mitochondrial complexes of roots and *** differences between the two tissues were observed in the mitochondrial import/export apparatus,the formation of super-complexes in the oxidative phosphorylation pathway,and specific interactions between enzymes of the TCA cycle that we postulate may be related to the metabolic/energetic requirements of roots and shoots.

关键词： mitochondrial complexes BN-PAGE size-exclusion chromatography TCA cycle