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Earthquake Engineering and Engineering Vibration 2021年第1期20卷 245-256页

作者： Jesus Fernandez-Ruiz Luis E.Medina Rodriguez pedro Alves Costa margarita martinez-Diaz University of La Coruna Department of Civil EngineeringCampus de ElvinaLa Coruna 15071Spain University of Porto Faculty of EngineeringRua Dr.Roberto Friass/n Porto4200-465Portugal University of La Coruna Department of Naval and Industrial EngineeringCampus de ElvinaLa Coruna 15071Spain

In the last 30 years,the scientific community has developed and proposed different models and numerical approaches for the study of vibrations induced by railway *** of them are formulated in the frequency/wave number domain and with a 2.5D ***-dimensional numerical models formulated in the time/space domain are less frequently used,mainly due to their high computational ***,these models present very attractive characteristics,such as the possibility of considering nonlinear behaviors or the modelling of excess pore pressure and non-homogeneous and non-periodic geometries in the longitudinal direction of the *** this study,two 3D numerical approaches formulated in the time/space domain are compared and experimentally *** first one consists of a finite element approach and the second one of a finite difference *** experimental validation in an actual case situated in Carregado(Portugal)shows an acceptable fitting between the numerical results and the actual measurements for both ***,there are some differences among *** study therefore includes some recommendations for their use in practical soil dynamics and geotechnical engineering.

关键词： railway vibrations time/space domain 3D numerical model finite difference method implicit finite element method

Cell deaths:Involvement in the pathogenesis and intervention therapy of CoVID-19

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Signal Transduction and Targeted Therapy 2022年第7期7卷 2272-2292页

作者： Xue Li Ziqi Zhang Zhenling Wang pedro Gutiérrez-Castrellón Huashan Shi department of Biotherapy State Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan UniversityNo.17Block 3Southern Renmin RoadChengduSichuan 610041People’s Republic of China Laboratory of Aging Research and Cancer drug Target State Key Laboratory of BiotherapyNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityNo.17Block 3Southern Renmin RoadChengduSichuan 610041People’s Republic of China State Key Laboratory of Biotherapy and Cancer Center West China HospitalSichuan Universityand Collaborative Innovation Center of BiotherapyKe Yuan 4th RoadGao Peng StreetChengduSichuan 610041People’s Republic of China Center for Translational Research on Health Science Hospital General Dr.Manuel Gea Gonzalez.Ministry of HealthCalz.Tlalpan 4800Col.Secc.XVI14080Mexico cityMexico

The current pandemic of coronavirus disease 2019(CoVID-19)caused by severe acute respiratory syndrome coronavirus 2(SARSCoV-2)infection has dramatically influenced various aspects of the *** is urgent to thoroughly study pathology and underlying mechanisms for developing effective strategies to prevent and treat this threatening *** is universally acknowledged that cell death and cell autophagy are essential and crucial to maintaining host homeostasis and participating in disease *** present,more than twenty different types of cell death have been discovered,some parts of which have been fully understood,whereas some of which need more *** studies have indicated that cell death and cell autophagy caused by coronavirus might play an important role in virus infection and ***,the knowledge of the interactions and related mechanisms of SARS-CoV-2 between cell death and cell autophagy lacks systematic ***,in this review,we comprehensively delineate how SARS-CoV-2 manipulates diverse cell death(including apoptosis,necroptosis,pyroptosis,ferroptosis,and NETosis)and cell autophagy for itself benefits,which is simultaneously involved in the occurrence and progression of CoVID-19,aiming to provide a reasonable basis for the existing interventions and further development of novel therapies.

关键词： pathogenesis thoroughly urgent

Pure Hydrocarbons:An Efficient Molecular design Strategy for the Next Generation of Host materials for Phosphorescent organic Light-Emitting Diodes

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Accounts of materials Research 2022年第3期3卷 379-390页

作者： Cyril Poriel joëlle Rault-Berthelot 不详 UniversitéRennes CNRSISCR-6226F-35000 RennesFrance

CoNSPECTUS:Fantastic progresses have been made since the discovery of phosphorescent organic light-emitting diodes(PhoLEDs)in 1998(Nature 1998,395,151).In the emissive layer of a PhoLED,a heavy-metal complex(emitter)is dispersed as a guest in an organic semiconductor(host)in order to harvest both singlet and triplet *** host/guest technique is essential to reach highperformance ***,designing high-efficiency host materials for red,green,and blue phosphors has been the main driving force of the ***,the most efficient PhoLEDs report very high external quantum efficiency(EQE)above 27%for the three *** molecular design of these high-efficiency host materials is based on small functional units,which have a crucial role in the device *** functional units are constructed on the assembly of electron-rich and/or electron-poor molecular fragments(such as carbazole,phenylamine,phosphine oxide,oxadiazole,pyridine,sulfone,etc.),which allows to finely tune the molecular orbitals energy levels(HoMo and LUMo)and the mobility of the charge carriers(hole and electrons).However,these molecular fragments incorporate heteroatoms,which in turn increase the molecular design complexity and production cost of the target materials and also create potential instability in the ***,the fragile C−N,C−P,and C−S bonds of such heteroatom-based hosts are involved,in part,in the oLED *** the instability of oLEDs is one of the most important problem to a.dress at the current stage of development,developing new generations of host materials,without heteroatoms,has appeared as an important challenge in the *** recent years,this new generation of host materials,called Pure HydroCarbons(PHC),only incorporating carbon and hydrogen atoms,has drawn the attention of the scientific *** host materials only contain benzene rings,one of the most robust and inert building unit,which are assemble with suitable linkages to a

关键词： Strategy Host Molecular

Flotation and surface modification characteristics of galena,sphalerite and pyrite in collecting-depressing-reactivating system

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journal of Central South University 2012年第6期19卷 1702-1710页

作者： T.H.PAK 孙体昌徐承焱 Y.H.jo School of Civil and Environment Engineering University of Science and Technology Beijing School of Mining Engineering University of Mining and Metallurgy Chongjin

The flotation tests and XPS analyses on galena,sphalerite and pyrite have been carried out in a collecting-depressing-reactivating system(hereafter referred as the Cdr system).In this system,sulfide minerals were first collected and activated by the collector,and then depressed strongly by Ca(oH)2 in the strong alkaline solution,and finally reactivated by *** flotation tests of pure minerals show that in this system the flotation behaviors of sphalerite and pyrite present irreversible characteristics along with the change of pulp ***,through the Cdr system,considerable differences in the flotabilities between galena and sphalerite/pyrite are also *** XPS analysis results for galena,sphalerite and pyrite in a Cdr system show that in the strong alkaline solution,some of the collectors,that have been already adsorbed on the mineral surface in the collecting process,are desorbed by Ca(oH)*** XPS analysis results also show that in H2So4 reactivating process,the surface hydroxides of galena are desorbed again by H2So4 and replaced by diethyl dithiocarbamate,but those of sphalerite and pyrite are not *** flotation system may be applied to the bulk-differential flotation process of sulfur-bearing low-grade lead-zinc ores.

关键词： Cdr system XPS analysis galena sphalerite pyrite

In vivo optical quality of posterior-chamber phakic implantable collamer lenses with a central port

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Eye and Vision 2021年第5期8卷 295-302页

作者： Robert Montés-Micó Francisco Pastor-Pascual Enrique Artiaga-Elordi Ramón Ruiz-Mesa pedro Tañá-Rivero optics and optometry&Vision Sciences department University of Valenciac/o Dr Moliner 5046100 ValenciaSpain oftalvist Clinic ValenciaSpain

Background:The aim of this review is to summarize the optical quality results in patients following the implantation of the V4c implantable collamer lens with a central port(ICL,STAAR Surgical Inc.).main text:A literature search in several databases was carried out to identify those publications,both prospective,retrospective and/or comparative with other refractive surgery procedures,reporting optical outcomes of patients who were implanted with the V4c ICL model.A total of 17 clinical studies published between 2012 and 2021 were included in this review.A detailed analysis of the available data was performed including number of eyes,follow-up and preoperative spherical ***,the review focused on several optical parameters including higher-order aberrations(HoAs),modulation transfer function(MTF)cut-off frequency and Strehl *** review encompassed a total of 817 eyes measured using different optical devices based on hartmann-Shack,retinal image quality measurement and ray-tracing technologies at different ***:The outcomes found in this review lead us to conclude that the ICL V4c model provides good optical quality,by means of different metrics,when implanted.

关键词： Implantable collamer lens Phakic optical quality Higher order aberrations Modulation transfer function

杂原子修饰的碳纳米管对高级氧化过程的催化性能(英文)

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催化学报 2014年第6期35卷 896-905页

作者： joo Restivo Raquel P.Rocha Adrián M.T.Silva josé J.M.órfo manuel F.R.Pereira josé L.Figueiredo Laboratory of Catalysis and materials-Associate Laboratory LSRE/LCM Faculty of Engineering University of Porto Rua Dr.Roberto Frias 4200-465 Porto Portugal

Multi-walled carbon nanotubes (CNTs) were submitted to chemical and thermal treatments in order to incorporate different heteroatoms on the surface. o-, S- and N-containing groups were successfully introduced onto the CNTs without significant changes of the textural properties. The cata-lytic activity of these heteroatom-modified CNTs was studied in two liquid phase oxidation processes: catalytic ozonation and catalytic wet air oxidation (CWAo), using oxalic acid and phenol as model compounds. In both cases, the presence of strongly acidic o-containing groups was found to decrease the catalytic activity of the CNTs. on the other hand, the introduction of S species (mainly sulfonic acids) enhanced the removal rate of the model compounds, particularly in the CWAo of phenol. Additional experiments were performed with a radical scavenger and sodium persulfate, in order to clarify the reaction mechanism. Nitrogen functionalities improve the catalytic performance of the original CNTs, regardless of the process or of the pollutant.

关键词：多壁碳纳米管催化性能高级氧化技术杂原子修饰模型化合物含氮基团催化湿式氧化

Bubble Dynamics and Heat Transfer on Biphilic Surfaces:Experiments and Numerical Simulation

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journal of Bionic Engineering 2020年第4期17卷 809-821页

作者： pedro Pontes Ricardo Cautela Emanuele Teodori Ana Sofia Moita Anastasios Georgoulas António Luís Nobre Moreira Moreira IN+-Center for Innovation Technology and Policy ResearchDepartment of Mechanical EngineeringInstituto Superior TécnicoUniversidade de LisboaAv.Rovisco Pais1049-001 LisboaPortugal ASML Holding N.V. De Run 65015504 DRVeldhovenThe Netherlands department of Exact Sciences and Engineering Portuguese Military AcademyR.Gomes Freire2031169-203 LisboaPortugal Advanced Engineering Centre School of ComputingEngineering and MathematicsCockcroft BuildingLewes RoadUniversity of Brighton BN24GJUK

Wettability is known to play a major role in enhancing pool boiling heat *** this context bioinspired surfaces can bring significant advantages in pool boiling *** work a.dresses a numerical investigation of bubble growth and detachment on a biphilic surface pattern,namely in a superhydrophobic region surrounded by a hydrophilic *** characteristics resemble bioinspired solutions explored in our research group,mainly considering the main topographical *** numerical approach is intended to provide additional information to an experimental approach,allowing to obtain temperature,pressure and velocity fields in and around the bubble,which help to describe bubble *** model was validated based on experimental data obtained with extensive image processing of synchronized high-speed video and high-speed thermographic *** results obtained here clearly evidence that combining enhanced direct numerical simulations with high-resolution transient experimental measurements is a promising tool to describe the complex and intricate hydrodynamic and heat transfer phenomena governing pool boiling on heated biphilic surfaces.

关键词： bioinspired biphilic surfaces bubble dynamics two-phase heat transfer time resolved infrared thermography CFD model

Silibinin induces hepatic stellate cell cycle arrest via enhancing p53/p27 and inhibiting Akt downstream signaling protein expression

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Hepatobiliary & Pancreatic Diseases International 2017年第1期16卷 80-87页

作者： devaraj Ezhilarasan jonathan Evraerts Brice Sid pedro Buc Calderon Sivanesan Karthikeyan Etienne Sokal Mustapha Najimi institut de recherche expérimentale et clinique (irec) laboratory of pediatric hepatology and cell therapyuniversité catholique de louvain，1200，Brussels，Belgium louvain drug research institute toxicology and cancer biology research group pmnt unituniversité catholique de louvain，1200，Brussels，Belgium facultad de ciencias de la salud universidad arturo prat，Iquique，Chil department of pharmacology and environmental toxicology food and hepatotoxicology laboratory dr. alm post graduate institute of basic medical sciences university of madrastaramani campus，Chennai-600 l13，India

BACKGRoUND： Proliferation of hepatic stellate cells （HSCs） plays a pivotal role in the progression of liver fibrosis conse- quent to chronic liver injury. Silibinin, a flavonoid compound, has been shown to possess anti-fibrogenic effects in animal models of liver fibrosis. This was attributed to an inhibition of cell proliferation of activated HSCs. The present study was to gain insight into the molecular pathways involved in silibinin anti-fibrogenic effect. METHoDS： The study was conducted on LX-2 human stellate cells treated with three concentrations of silibinin （10, 50 and 100 μmol/L） for 24 and 96 hours. At the end of the treatment cell viability and proliferation were evaluated. Protein expression of p27, p21, p53, Akt and phosphorylated-Akt was evaluated by Western blotting analysis and Ki-67 protein expression was by immunocytochemistry. Sirtuin activity was evaluated by chemiluminescence based assay. RESULTS： Silibinin inhibits LX-2 cell proliferation in doseand time-dependent manner; we showed that silibinin upregulated the protein expressions of p27 and p53. Such regulation was correlated to an inhibition of both downstream Akt and phosphorylated-Akt protein signaling and Ki-67 protein expression. Sirtuin activity also was correlated to silibinin- inhibited proliferation of LX-2 cells. CoNCLUSIoN： The anti-proliferative effect of silibinin on LX-2 human steUate cells is via the inhibition of the expres- sions of various cell cycle targets including p27, Akt and sir- tuin signaling.

关键词： silibinin hepatic stellate cells in vitro cell cycle arrest proliferation

New In Vitro Studies on the Bioprofile of Genista tenera Antihyperglycemic Extract

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Natural Products and Bioprospecting 2015年第6期5卷 277-285页

作者： Daniela Batista pedro L.Falé maria L.Serralheiro maria E.Araújo Paulo J.A.madeira Carlos Borges Isabel Torgal margarida Goulart jorge Justino Alice martins Amélia P.Rauter Centro de Química e Bioquímica Faculdade de CiênciasUniversidade de LisboaCampo Grande1749-016 LisbonPortugal Institute of Pharmaceutical Science King’s College London150 Stamford StreetLondon SE19NHUK Escola Superior Agrária de Santarém Quinta do Galinheiro2001-904 SantarémPortugal

The inhibition of a-glucosidase and glucose-6-phosphatase,two enzymes involved in the carbohydrate metabolism,is an important target to control glycaemia on individuals with type 2 *** this work we report for the first time the inhibition of both enzymes by the antihyperglycemic n-butanol extract from Genista tenera(Fabaceae).This extract decreased a-glucosidase and glucose-6-phosphatase activities to 0.97 and 80.25%,respectively,being more effective than acarbose,and phlorizin,the positive controls,which reduced enzymes activities only to 17.39 and 96.06%.once inflammation and oxidative stress are related to diabetic impairments,the anti-inflammatory activity of the extract was also evaluated,through its inhibitory activity over CoX-1 enzyme(47.5%inhibition).Moreover,after induction of oxidative stress by UV radiation,the viability of irradiated rat liver hepatoma cells exposed to the extract was significantly higher(67.82%)than that promoted by ascorbic acid,the positive control(45.05%).In addition,the stability of the extract under gastrointestinal conditions was evaluated by HPLC–DAD-ESI–MS/*** diglycosides were identified as the main constituents of the extract,and no alterations in the chemical composition nor in the antioxidant activity were observed after in vitro digestion with artificial gastric and pancreatic juices.

关键词： a-Glucosidase inhibition In vitro digestion HPLC-DAD-ESI-MS/MS Antioxidant activity Flavonoid glycosides

Gross Chemical Profile and Calculation of Nitrogen-to-Protein Conversion Factors for Five Tropical Seaweeds

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American journal of Plant Sciences 2011年第3期2卷 287-296页

作者： Graciela S.Diniz Elisabete Barbarino joão oiano-Neto Sidney Pacheco Sergio o.Lourenco departamento de Biologia marinha Universidade Federal FluminenseNiteróiBrazil Laboratório de Cromatografia Líquida Embrapa Agroindústria de AlimentosRio de JaneiroBrazil Instituto Virtual Internacional de Mudanças Globais Universidade Federal do Rio de Janeiro—UFRJ/IVIGRio de JaneiroBrazil

despite decades of research on marine algae, there are still significant gaps in basic knowledge about chemical composition of these organisms, especially in tropical environments. In this study, the amino acid composition and contents of total nitrogen, phosphorus, lipid, carbohydrate and protein were determined in Asparagopsis taxiformis, Centroceras clavulatum, Chaetomorpha aerea, Sargassum filipendula and Spyridia hypnoides. The seaweeds showed low lipid contents (lower than 5.5% d.w. in all species) and were rich in carbohydrates (more than 16% d.w. in all seaweeds). The percentage of nitrogen, phosphorus and protein varied widely among species, which red algae showed the highest con-centrations. The amino acid composition was similar among the seaweeds, which glutamic acid, aspartic acid and leu-cine as the most abundant. All species are poor in histidine. An average of 24.2% of the total nitrogen is non-proteinaceous. From data of total amino acid and total nitrogen, specific nitrogen-to-protein conversion factors were calculated for each species. The nitrogen-to-protein conversion factors calculated ranged from 4.51 to 5.21, with an overall average of 4.86. These findings show that the traditional conversion factor of 6.25 should be avoided for seaweeds, since it overestimates the actual protein content.

关键词： Nitrogen-to-Protein Conversion Factors Protein Amino Acid Seaweeds Element Composition Tropical Environment