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Optimization of high-speed railway pantographs for improving pantograph-catenary contact

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Theoretical & Applied Mechanics Letters 2013年第1期3卷 51-57页

作者： Jorge Ambrósio Joo Pombo Manuel pereira IDMEc-IST Technical Univ. of Lisbon Av. Rovisco Pais

a.c.ucial system for the operation of high-speed trains is the pantograph catenary interface as it is the sole responsible to deliver electrical power to the train. Being the catenary a stationary system with a long lifespan it is also less likely to be redesigned and upgraded than the pantographs that fit the train vehicles. This letter proposes an optimization procedure for the improvement of the contact quality between the pantograph and the catenary solely based on the redesign of the pantograph head suspension characteristics. A pantograph model is defined and validated against experimental dynamic characteristics of existing pantographs. An optimization strategy based on the use of a global optimization method, to find the vicinity of the optimal solution, followed by the use of a deterministic optimization algorithm, to fine tune the optimal solution, is applied here. The spring stiffness, damping characteristics and bow mass are the design variables used for the pantograph optimization. The objective of the optimal problem is the minimization of the standard deviation of the contact force history, which is the most important quantity to define the contact quality. The pantograph head suspension characteristics are allowed to vary within technological realistic limits. It is found that current high-speed railway pantographs have a limited potential for mechanical improvements, not exceeding 10% 15% on the decrease of the standard deviation of the contact force. c 2013 The chinese Society of Theoretical and Applied Mechanics. [doi：10.1063/2.1301306]

关键词： high-speed railway pantograph

Ecological study of gastric ca.c.r in Brazil:Geographic and time trend analysis

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World Journal of Gastroenterology 2014年第17期20卷 5036-5044页

作者： césar Augusto Amorim Jéssica Pronestino Moreira Luisa Rial Antonio José carneiro Homero Soares Foga?a.c.leste Elia Ronir Raggio Luiz Heitor Siffert pereira de Souza Servi?o de Gastroenterologia Departamento de Clínica MédicaHospital UniversitárioUniversidade Federal do Rio de JaneiroRio de JaneiroRJ 21941-913Brazil Instituto de Epidemiologia e Saúde coletiva Universidade Federal do Rio de JaneiroRio de JaneiroRJ 21941-913Brazil

AIM: To investigate the geographic distributions and time trends of gastric ca.c.r (Gc) incidence and mortality in Brazil.

关键词： Gastric ca.c.r Ecological study Hospitalization Lethality rate

Seaweeds’nutraceutical and biomedical potential in ca.c.r therapy:a.c.ncise review

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Journal of ca.c.r Metastasis and Treatment 2021年第1期7卷 189-212页

作者： João cotas Diana Pacheco Ana M.M.Gonçalves Paulo Silva Loïc G.carvalho Leonel pereira University of coimbra MARE-Marine and Environmental Sciences CentreDepartment of Life SciencesCalçada Martim de FreitasCoimbra 3000-456Portugal Department of Biology and cESAM University of AveiroAveiro 3810-193Portugal UcIBIO-REQUIMTE Departamento de QuímicaFaculdade de Ciências e TecnologiaUniversidade Nova de LisboaCaparica 2829-516Portugal The James Hutton Institute Dundee DD25DAScotlandUK Heriot-Watt University Edinburgh EH144ASScotlandUK.

Seaweeds have been a food source since a.c.ent times(600 Bc)and are still widely used in Asia,mainly in traditional chinese medicine and Japanese folk ***,seaweed compounds and extracts have been gaining interest from the biomedical and pharmaceutical market *** have been referenced as feasible solutions in finding new potential compounds and therapies in prevention,control,and reduction of ca.c.r development due to the multirole of some bioactive components(e.g,phenolic compounds and sulphated polysa.c.arides).Moreover,seaweeds are rich in important health-promoting molecules[such as poly and highly unsaturated fatty acids(PUFAs and HUFAs),essential amino acids,vitamins,and dietary fibers]and minerals(ca.c.um,iron,iodine,magnesium,phosphorus,potassium,zinc,copper,manganese,selenium,and fluoride).In this review,the potential therapeutic effects of seaweed in the prevention and treatment of ca.c.r are approached,as well as nutraceutical properties of seaweed to promote cell homeostasis.

关键词： Seaweed compounds nutraceutical bioactive molecules ca.c.r prevention ca.c.r treatment

Ecosystem services of the Baltic Sea:An assessment and mapping perspective

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Geography and Sustainability 2020年第4期1卷 256-265页

作者： Miguel Inácio Donalda Karnauskaitė EglėBaltranaitė Marius Kalinauskas Katarzyna Bogdzevič Eduardo Gomes Paulo pereira Environmental Management Laboratory Mykolas Romeris UniversityVilniusLithuania Marine Resea.c. Institute Klaipeda UniversityKlaipedaLithuania

The Baltic Sea is essential for marine ecosystem services(MES)provision and the region’s socio-economic *** is considered one of the busiest and most polluted regional seas in *** recent years a.c.llective effort in enforcing European and regional environmental policies and directives(*** Framework Direc-tive 2000/60/Ec,2000;Marine Strategy Framework Directive 2008/56/Ec,2008;Maritime Spatial Planning Directive 2014/89/EU,2014)has been carried *** Services assessment and mapping is integrated into these *** increasing number of scientific studies,projects,and other works were developed in this context,generating a vast body of *** all efforts to improve the Baltic Sea’s environmental status,the targets established were not *** is also important to analyze if current methodological approaches for assessing and mapping MES are robust enough to provide the needed *** perspective paper analyses the status of assessment and mapping *** results showed that most of the studies were focused on qualitative assessments,with limited validation and *** the number of robust and quantitative works is increasing,more are *** is vital to carry out quantitative assessments to inform decision-makers better and standardize MES practices across the Baltic Sea.

关键词： collaborative effort Ecological modeling Marine ecosystem services cultural Provisioning Regulating

Apolipoprotein E polymorphism influences orthotopic liver transplantation outcomes in patients with hepatitis c virus-induced liver cirrhosis

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World Journal of Gastroenterology 2021年第11期27卷 1064-1075页

作者： José carlos Rodrigues Na.c.mento Lianna.c.pereira Juliana Magalhães c Rêgo Ronaldo P Dias Paulo Goberlânio B Silva Silvio Alencar c Sobrinho Gustavo R coelho Ivelise Regina.c.Brasil Edmilson F Oliveira-Filho James S Owen Pierluigi Toniutto Reinaldo B Oriá Department of Anesthesia and Surgery Liver Transplantation Fortaleza General HospitalFortaleza 60150-160CEBrazil Laboratory of the Biology of Tissue Healing Ontogeny and NutritionDepartment of Morphology and Institute of BiomedicineSchool of MedicineFederal University of CearáFortaleza 60430-270CEBrazil Department of Dental clinic Federal University of CearáFortaleza 60430-270CEBrazil Department of Surgery Liver Transplant Unit of Federal University of CearáFortaleza 60430-270CEBrazil Transplantation Division Hospital Geral de FortalezaFortaleza 60175-742CEBrazil Institute of Virology CharitéUniversitätsmedizin BerlinBerlin 10117Germany UcL Medical School Royal Free CampusLondon NW32PFUnited Kingdom Department of Specialized Medicine Hepatology Liver Transplantation UnitAzienda Sanitaria Universitaria Integrata of UdineUdine I-33100Italy

BAcKGROUND Hepatitis c virus(HcV)infection is responsible for a.c.ronic liver inflammation,which may cause end-stage liver disease and hepatocellular *** E(protein:ApoE,gene:APOE),a key player in cholesterol metabolism,is mainly synthesized in the liver and APOE polymorphisms may influence HcV-induced liver *** To determine whether APOE alleles affect outcomes in HcV-infected patients with liver cirrhosis following orthotopic liver transplantation(OLT).METHODS This was a.c.hort study in which 179 patients,both genders and aged 34-70 years,were included before or after(up to 10 years follow-up)*** injury severity was assessed using different criteria,including METAVIR and models for endstage liver *** polymorphisms were analyzed by quantitative real-time polymerase chain *** The APOE3 allele was the most common(67.3%).In inflammation severity of biopsies from 89 OLT explants and 2 patients in pre-transplant,the degree of severe inflammation(A3F4,0.0%)was significantly less frequent than in patients with minimal and moderate degree of inflammation(≤A2F4,16.2%)P=0.048,in patients carrying the APOE4 allele when compared to *** addition,a significant difference was also found(≤A2F4,64.4%vs A3F4,0.0%;P=0.043)and(A1F4,57.4%vs A3F4,0.0%;P=0.024)in APOE4 patients when compared to APOE3 *** fibrosis degree of the liver graft in 8 of 91 patients and the lack of the E4 allele was associated with more moderate fibrosis(F2)(P=0.006).cONcLUSION Our results suggest that the E4 allele protects against progression of liver fibrosis and degree of inflammation in HcV-infected patients.

关键词： Apolipoprotein E Polymorphism Liver cirrhosis Hepatitis c virus Hepatocellular ca.c.noma Liver transplantation

cationic antimicrobial protein of Mr 37 kDa:a multifunctional inflammatory protein

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chinese Medical Journal 2001年第1期114卷 9-13页

作者： H.Anne pereira Department of Pathology University of Oklahoma Health Sciences CenterOklahoma 73190USA

PURPOSE: To investigate the role of cationic antimicrobial protein of Mr 37 kDa (cAP37) a neutrophil-derived inflammatory mediator on endothelial cell function. DATA SOURcES: Endothelial cells used in this study were obtained from human lung microvessels and rat aorta. The latter was a kind gift of Dr. Paula Grammas. The mono-mac 6 cell line used in this study was the generous gift of Dr. H.W. Loms Ziegler-Heitbrock. STUDY SELEcTION AND DATA EXTRAcTION: Endothelial cell proteins kinase c activity was determined by measuring ca.c.um- and phospholipid-dependent phosphorylation of histone. Endothelial cell migration was determined using costar Transwell apparatus. cell surface expression of adhesion molecules, IcAM-1 and PEcAM-1 was determined using flow cytometry. RT-PcR was used to amplify the cAP37 from endothelial cells treated with LPS. RESULTS: We demonstrated that cAP37 which was originally identified as having potent antimicrobial activity and chemotactic activity for monocytes was capable of modulating endothelial cell functions. cAP37 activated endothelial cell protein kinase c in a dose- and time-dependent fashion. Importantly cAP37 increased the adhesive properties of the endothelium for monocytes. cAP37 upregulated the well known adhesion molecules, IcAM-1 and PEcAM-1 in a dose- and time-dependent manner. In addition, cAP37 promoted endothelial cell migration. Further investigations indicated that cAP37 was induced in endothelial cells in response to pro-inflammatory cytokines such as tumor necrosis factor-alpha and interleukin-1 alpha as well as inflammatory mediators such as lipopolysa.c.aride. Unstimulated endothelial cells did not constitutively express cAP37. The cDNA sequence of endothelial cAP37 was determined and found to be highly homologous to the sequence obtained for neutrophil-derived cAP37. cONcLUSIONS: Our studies strongly suggest that cAP37 plays a pivotal role in monocyte-endothelial interactions and the transmigration of monocytes from th

关键词： cationic antimicrobial protein Mr 37 kDa inflammatory mediator function

Analysis of 12 variants in the development of gastric and colorectal ca.c.rs

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World Journal of Gastroenterology 2017年第48期23卷 8533-8543页

作者： Giovanna.c.cava.c.nte Ma.c.s AT Amador Andre M Ribeiro dos Santos Darlen c carvalho Roberta B Andrade Esdras EB pereira Marianne R Fernandes Danielle F costa Ney Pc Santos Paulo P Assumpcao Andrea Ribeiro dos Santos Sidney Santos Laboratório de Genética Humana e Médica Universidade Federal do Pará Núcleo de Pesquisas em Oncologia Universidade Federal do Pará

AIM To evaluate the relation between 12 polymorphisms and the development of gastric ca.c.r(Gc) and colorectal ca.c.r(cRc).METHODS In this study,we included 125 individuals with Gc diagnosis,66 individuals with cRc diagnosis and 475 ca.c.r-free individuals. All participants resided in the North region of Brazil and authorized the use of their samples. The 12 polymorphisms(in cASP8,cYP2 E1,cYP19 A1,IL1 A,IL4,MDM2,NFKB1,PAR1,TP53,TYMS,UGT1 A1 and XRcc1 genes) were genotyped in a single PcR for each individual,followed by fragment analysis. To avoid misinterpretation due to population substructure,we applied a previously developed set of 61 a.c.stryinformative markers that can also be genotyped by multiplex PcR. The statistical analyses were performed in Structure v.2.3.4,R environment and SPSS *** After statistical analyses with the control of confounding factors,such as genetic a.c.stry,three markers(rs79071878 in IL4,rs3730485 in MDM2 and rs28362491 in NFKB1) were positively associated with the development of Gc. One of these markers(rs28362491) and the marker in the UGT1 A1 gene(rs8175347) were positively associated with the development of cRc. Therefore,we investigated whether the joint presence of the deleterious alleles of each marker could affect the development of ca.c.r and we obtained positive results in all analyses. carriers of the combination of alleles RP1 + DEL(rs79071878 and rs28361491,respectively) are at 10-times greater risk of developing Gc than carriers of other combinations. Similarly,carriers of the combination of DEL + RARE(rs283628 and rs8175347) are at about 12-times greater risk of developing cRc than carriers of other *** These findings are important for the comprehension of gastric and cRc development,particularly in highly admixed populations,such as the Brazilian population.

关键词： Inflammatory processes Immune response Genomic and cellular stability Gastric ca.c.r colorectal ca.c.r Amazon

Adsorbents Derived from Xylan Hemicellulose with Removal Properties of Pollutant Metals

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chinese Journal of Polymer Science 2023年第6期41卷 874-886,I0007页

作者： Elizabeth Elgueta Yerko Becerra Ana Martínez Miguel pereira Isabel carrillo-Varela Felipe Sanhueza Dariela Nuez BernabéL.Rivas centro de Investigación de Polímeros Avanzados CIPAAvenida Collao 1202Edificio de LaboratoriosConcepcionChile Departamento de Química Ambiental Facultad de CienciasUniversidad Católica de la Santísima ConcepciónCaila 160-cConcepcionChile Polymer Department Faculty of ChemistryUniversity of ConcepciónCasilla 160-CConcepcionChile Departamento de Ingeniería Química Facultad de IngenieríaUniversidad de ConcepciónConcepcionChile Department of Materials Engineering Faculty of EngineeringUniversidad de ConcepciónConcepcionChile

The adsorption capacity of hydrogels derived from modified xylan hemicellulose has been tested in order to develop new bio-based adsorbent materials useful for removing metal ions pollutants,such as cd(Ⅱ),cu(Ⅱ)and Pb(Ⅱ)from an aqueous *** was extracted from bleached kraft pulp of eucalyptus and subsequently modified with different proportions of functional sulfonic acid groups(HA3-HA7)and sulfonate groups(HS30-HS70)to generate *** results showed that all the synthesized hydrogels were capable of adsorbing metal ions,being the hydrogels with 30%and 50%xylan the ones that presented the highest adsorption *** capacity studies at different initial concentrations revealed that at an initial concentration of 300 mg·L-1,the HA3 hydrogel presented an adsorption capacity of 193mg Pb(Ⅱ),182 mg cd(Ⅱ),and 66 mg cu(Ⅱ)per g *** HA5 hydrogel presented a.c.pacity of 185 mg Pb(Ⅱ),113 mg cd(Ⅱ),and 48 mg cu(Ⅱ)per g *** HS30 hydrogel exhibited an adsorption of 205 mg Pb(Ⅱ),174 mg cd(Ⅱ),and 71 mg cu(Ⅱ)per g hydrogel,and HS50 hydrogel exhibited an adsorption capacity of 273 mg Pb(Ⅱ),143 mg cd(Ⅱ),and 45 mg cu(Ⅱ)per g *** results show that modified Xylan hemicellulose is a promising adsorbent for removal cd(Ⅱ),cu(Ⅱ),and Pb(Ⅱ)ions from aqueous solutions.

关键词： Pb(Ⅱ) solution capacity

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对FAO推荐的作物系数计算方法的验证

农业工程学报 2000年第5期16卷 26-30页

作者：刘钰 L.S.pereira 中国水利水电科学研究院水利所葡萄牙里斯本技术大学农学院农业工程系

作物系数是计算作物需水量必不可少的参数。该文介绍了 FAO近期推荐的确定作物系数的 2种计算方法 ,一种是比较简单实用的分段单值平均法 ,另一种是比较复杂但相对准确的双值作物系数法。用河北省雄县灌溉试验站的冬小麦、夏玉米田间土... 详细信息

作物系数是计算作物需水量必不可少的参数。该文介绍了 FAO近期推荐的确定作物系数的 2种计算方法 ,一种是比较简单实用的分段单值平均法 ,另一种是比较复杂但相对准确的双值作物系数法。用河北省雄县灌溉试验站的冬小麦、夏玉米田间土壤水分观测资料计算作物实际腾发量 ,对上述 2种确定作物系数的方法进行了检验。计算的作物系数与雄县试验站的实测结果基本接近 ,从而初步证明了在缺少实测资料的情况下可以采用

关键词：作物系数计算方法水量平衡冬小麦夏玉米