检索结果-南通市图书馆

Friction and wear performance of polyether ether ketone(PeeK)polymers in three lubrication regimes

在线全文

学校读者我要写书评

暂无评论

Friction 2024年第4期12卷 670-682页

作者： Davide MASSOCCHI Nora LeCIS Marco LATTUADA Davide SCAGLIA Steven CHATTeRTON paolo PeNNACCHI Department of Mechanical engineering Politecnico di MilanoMilan 20156Italy eni SpA Downstream product R&DLombardia 20097Italy eurobearings S.R.L. Lombardia 29016Italy

This experimental study investigates the friction and wear of three coatings commonly used in industrial applications,particularly in hydrodynamic *** three materials under investigation were Babbitt,polyether ether ketone(PeeK)reinforced with 15%carbon fibers,and PeeK reinforced with 20%carbon *** first polymer material was extruded,while the other was produced by fused deposition modelling(FDM).The materials were subjected to sliding tests in a pin-on-disc configuration,with a steel ball serving as the counter *** tests were conducted at room temperature,with a load of 10 N and under three different lubrication conditions:dry,grease,and *** linear speed was set at 0.3 m/s for the dry and semi-solid lubrication tests,while for the oil tests,the speed was set at 0.25 m/*** greases used had consistency grades of NGLI 000 and NGLI *** ISO VG 68 circulation oil was used for the oil lubrication ***,thermodynamic analyses were performed under the most severe conditions(i.e.,dry)to investigate the steel-Babbitt and steel-PeeK contact.

关键词： hydrodynamic bearings polyether ether ketone(PeeK)polymers additive manufacturing grease lubrication sliding oil lubrication ball-on-disk tribology

Final results of the first phase of the PROTO-SPHeRA experiment: obtainment of the full current stable screw pinch and first evidences of the jet + torus combined plasma configuration

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Plasma Science and Technology 2024年第2期26卷 31-43页

作者： paolo MICOZZI Franco ALLADIO Alessandro MANCUSO Vincenzo ZANZA Gerarda APRUZZeSe Francesca BOMBARDA Luca BONCAGNI paolo BURATTI Francesco FILIPPI Giuseppe GALATOLA TeKA Francesco GIAMMANCO edmondo GIOVANNOZZI Andrea GROSSO Matteo IAFRATI Alessandro LAMPASI Violeta LAZIC Simone MAGAGNINO Simone MANNORI paolo MARSILI Valerio PIeRGOTTI Giuliano ROCCHI Alessandro SIBIO Benedetto TILIA Onofrio TUDISCO FSN Dipartimento Fusione e tecnologie per la Sicurezza Nucleare ENEA Agenzia Nazionale per Le Nuove Tecnologie Energia e lo Sviluppo Economico SostenibileFrascati(Rome)00044Italy IAPS Istituto di Astrofisica e Planetologia Spaziali INAF Istituto Nazionale di AstrofisicaRome O133Italy Physics Department University of Pisa Faculty of Natural Sciences Mathematics and PhysicsPisa 56127 Italy

In astrophysics, the boundary conditions for plasma phenomena are provided by nature and the astronomer faces the problem of understanding them from a variety of observations [Hester J J et al 1996 Astrophys. J. 456 225], on the other hand, in laboratory plasma experiments the electromagnetic boundary conditions become a major problem in the set-up of the machine that produces the plasma, an issue that has to be investigated step by step and to be modified and adapted with great patience, in particular in the case of an innovative plasma confinement experiment. The PROTO-SPHeRA machine [Alladio F et al 2006 Nucl. Fusion 46 S613] is a magnetic confinement experiment, that emulates in the laboratory the jet + torus plasma configurations often observed in astrophysics: an inner magnetized jet of plasma centered on the(approximate) axis of symmetry and surrounded by a magnetized plasma torus orthogonal to this jet. The PROTO-SPHeRA plasma is simply connected, i.e., no metal current conducting rod is linked to the plasma torus, while instead it is the inner magnetized plasma jet(in the following always called the plasma centerpost) that is linked to the torus. It is mandatory that no spurious plasma current path modifies the optimal shape of the plasma centerpost. Moreover, as the plasma torus is produced and sustained, in absence of any applied inductive electric field, by the inner plasma centerpost through magnetic reconnections [Taylor J B and Turner M F 1989 *** 29 219], it is required as well that spurious current paths do not surround the torus on its outboard, in order not to lower the efficiency of the magnetic reconnections that maintain the plasma torus at the expense of the plasma centerpost. Boundary conditions have been corrected,up to the point that the first sustainment in steady state has been achieved for the combined plasma.

关键词： laboratory plasmas magnetic confinement astrophysical plasmas

Shear-wave elastography to predict hepatocellular carcinoma after hepatitis C virus eradication:A systematic review and meta-analysis

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第10期30卷 1450-1460页

作者： Giorgio esposto paolo Santini Linda Galasso Irene Mignini Maria elena Ainora Antonio Gasbarrini Maria Assunta Zocco CeMAD Digestive Disease Center Fondazione Policlinico Universitario“A.Gemelli”IRCCSCatholic University of RomeRome 00168Italy Fondazione Policlinico Universitario Agostino Gemelli IRCCS Fondazione Policlinico Universitario Agostino Gemelli IRCCS-UniversitàCattolica del Sacro CuoreRome 00168Italy Medicina Interna e Gastroenterologia CEMAD Digestive Disease CenterUniversitàCattolica del Sacro CuoreFondazione Policlinico Universitario A Gemelli IRCCSRome 00168Italy

BACKGROUND Direct-acting antiviral agents(DAAs)are highly effective treatment for chronic hepatitis C(CHC)with a significant rate of sustained virologic response(SVR).The achievement of SVR is crucial to prevent additional liver damage and slow down fibrosis *** assessment of fibrosis degree can be performed with transient elastography,magnetic resonance elastography or shear-wave elastography(SWe).Liver elastography could function as a predictor for hepato-cellular carcinoma(HCC)in CHC patients treated with *** To explore the predictive value of SWe for HCC development after complete clearance of hepatitis C virus(HCV).MeTHODS A comprehensive literature search of clinical studies was performed to identify the ability of SWe to predict HCC occurrence after HCV *** accordance with the study protocol,a qualitative and quantitative analysis of the evidence was *** At baseline and after 12 wk of follow-up,a trend was shown towards greater liver stiffness(LS)in those who go on to develop HCC compared to those who do not[baseline LS standardized mean difference(SMD):1.15,95%confidence interval(95%CI):020-2.50;LS SMD after 12 wk:0.83,95%CI:0.33-1.98].The absence of a statistically significant difference between the mean LS in those who developed HCC or not may be related to the inability to correct for confounding factors and the absence of raw source *** was a statist-ically significant LS SMD at 24 wk of follow-up between patients who developed HCC vs not(0.64;95%CI:0.04-1.24).CONCLUSION SWe could be a promising tool for prediction of HCC occurrence in patients treated with *** studies with larger cohorts and standardized timing of elastographic evaluation are needed to confirm these data.

关键词： Shear-wave elastography Hepatocellular carcinoma Hepatitis C virus Sustained virologic response

Dynamic contrast enhanced ultrasound in differential diagnosis of hepatocellular carcinoma: A systematic review and meta-analysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2024年第6期16卷 2804-2815页

作者： Giorgio esposto paolo Santini Fabrizio Termite Linda Galasso Irene Mignini Maria elena Ainora Antonio Gasbarrini Maria Assunta Zocco Department of CeMAD Digestive Disease Center Fondazione Policlinico Universitario A Gemelli IRCCSCatholic University of RomeRome 00168Italy Department of Fondazione Policlinico Universitario Agostino Gemelli IRCCS UniversitàCattolica del Sacro CuoreRome 00168Italy Department of Medicina Interna e Gastroenterologia CEMAD Digestive Disease CenterFondazione Policlinico Universitario A Gemelli IRCCSUniversitàCattolica del Sacro CuoreRome 00168Italy

BACKGROUND Non-invasive differential diagnosis between hepatocellular carcinoma(HCC)and other liver cancer(*** or metastasis)is highly challenging and definitive diagnosis still relies on histological *** patterns of enhancement and wash-out of liver nodules can be used to stratify the risk of malignancy only in cirrhotic patients and HCC frequently shows atypical *** contrast-enhanced ultrasound(DCeUS)with standardized software could help to overcome these obstacles,providing functional and quantitative parameters and potentially improving accuracy in the evaluation of tumor *** To explore clinical evidence regarding the application of DCeUS in the differential diagnosis of liver *** A comprehensive literature search of clinical studies was performed to identify the parameters of DCeUS that could relate to histological *** accordance with the study protocol,a qualitative and quantitative analysis of the evidence was *** Rise time was significantly higher in HCC patients with a standardized mean difference(SMD)of 0.83(95%CI:0.48-1.18).Similarly,other statistically significant parameters were mean transit time local with a SMD of 0.73(95%CI:0.20-1.27),peak enhancement with a SMD of 0.37(95%CI:0.03-0.70),area wash-in area under the curve with a SMD of 0.47(95%CI:0.13-0.81),wash-out area under the curve with a SMD of 0.55(95%CI:0.21-0.89)and wash-in and wash-out area under the curve with SMD of 0.51(95%CI:0.17-0.85).SMD resulted not significant in fall time and wash-in rate,but the latter presented a trend towards greater values in HCC compared to intrahepatic *** DCeUS could improve non-invasive diagnosis of HCC,leading to less liver biopsy and early *** quantitative analysis needs to be applied on larger cohorts to confirm these preliminary results.

关键词： Dynamic contrast enhanced ultrasound Hepatocellular carcinoma Intracellular cholangiocarcinoma Quantitative ultrasound Liver cancer Time-intensity curve

The Literati＇s Polyphonic Answers to Social Changes in Late Imperial China

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of History in China 2017年第3期12卷 357-432页

作者： paolo santangelo Department of Asian and Oriental Studies La Sapienza University of Rome 00185 Rome Italy

The article aims to rethink the pluralistic intellectual currents and social changes of the last centuries in China： How literati reacted to the historical changes, the economic developments, the collapse of the hierarchical order, and the social mobility from the end of the Ming to the middle of the Qing dynasty. Urbanisation, the great silver inflow, the acceleration of trade, and social mobility raised new challenges to the orthodox view of the world and to Neo-Confucian norms. These new attitudes of the Chinese literati--which can be inferred both from literary and philosophical works--uncover new attitudes in the mental structure of the intellectual strata of the time. In the history of ideas we notice a progressive detachment from the orthodox view of the conflictual relationship between principle and desires, especially in the ambit of the Taizhou school. The elaboration of a new anthropological mindset aimed at the rehabilitation of passions and desires culminated with Li Zhi. This trend went on in the Qing period, from Wang Fuzhi to Dai Zhen. In literature, a similar trend, the so-called ＂cult of qing,＂ can be found with the moral justification of emotion-desire （establishing emotion as a genuine and active source of virtue）, and with the vitalistic identification of emotions as the source of life and reproduction. Another indication of change is the challenge of common and accepted truisms through the praise of ＂folly＂ in real life situations and literary works： To be ＂crazy＂ and ＂foolish＂ became a sign of distinction among certain intellectual circles, in contrast with the pedant orthodox scholars and officials and the vulgar nouveaux ziches. The unconventional character of the anti-hero Baoyu is emblematic, with his aversion for any kind of official ceremony and convention, his abnormal sensibility and impractical and naive mentality, and his consciousness of being different from others. The crisis of the established ladder of values can be seen in the e

关键词： literati modemisation desires and principles Li Zhi cult of qing,foolishness Yuan Mei retribution human responsibility

Laser-optimized Pt-Y alloy nanoparticles embedded in Pt-Y oxide matrix for high stability and ORR electrocatalytic activity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of energy Chemistry 2024年第5期92卷 508-520页

作者： Riccardo Brandiele Andrea Guadagnini Mattia Parnigotto Federico Pini Vito Coviello Denis Badocco paolo Pastore Gian Andrea Rizzi Andrea Vittadini Daniel Forrer Vincenzo Amendola Christian Durante Department of Chemical Sciences University of PaduaVia Marzolo 135131 PadovaItaly Istituto di Chimica della Materia Condensata e di Tecnologie per l’energia ICMATe-CNR via Marzolo 1 I-35131 PadovaItaly

The development of active yet stable catalysts for oxygen reduction reaction(ORR)is still a major issue for the extensive permeation of fuel cells into everyday *** nanostructured Pt catalysts are to date the best available systems in terms of activity,the same is not true for stability,particularly under operating *** this work,Pt_(Х)Y alloy nanoparticles are proposed as active and durable electrocatalysts for ***_(Х)Y nanoalloys are synthesized and further optimized by laser ablation in liquid followed by laser fragmentation in *** novel integrated laser-assisted methodology succeeded in producing Pt_(Х)Y nanoparticles with the ideal size(ercial Pt catalysts,yet resulting remarkably more active with e_(1/2)=0.943 V ***,specific activity=1095μA cm^(-2) and mass activity>1000 A g^(-1).At the same time,the nanoalloys are embedded in a fine Pt oxide matrix,which allows a greater stability of the catalyst than the commercial Pt reference,as directly verified on a gas diffusion electrode.

关键词： electrocatalysis GDe ORR Pt_(2)Y Pt_(3)Y LAL LFL Oxide support Pto Nanoalloys

Weak Merging Scenario of CLASH Cluster A209

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第4期24卷 174-182页

作者： Wen-Cheng Feng Heng Yu Hai-Hui Zhao Xiao-Lan Hou Shu-Mei Jia Cheng-Kui Li Yu-Lin Cheng paolo Tozzi Ming Sun Yong Chen Department of Physics and Institute of Theoretical Physics Nanjing Normal UniversityNanjing 210023China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Department of Astronomy Beijing Normal UniversityBeijing 100875China Department of Astronomy Yunnan UniversityKunming 650091China INAF—Osservatorio Astrofisico di Arcetri Largo E.Fermi50122 FirenzeItaly Department of Astronomy University of VirginiaP.O.Box 400325CharlottesvilleVA 22904-4325USA

We study the structural and dynamical properties of A209 based on Chandra and XMM-Newton *** obtain detailed temperature,pressure,and entropy maps with the contour binning method,and find a hot region in the NW *** X-ray brightness residual map and corresponding temperature profiles reveal a possible shock front in the NW direction and a cold front feature in the Se *** with the galaxy luminosity density map we propose a weak merger scenario.A young sub-cluster passing from the Se to NW direction could explain the optical subpeak,the intracluster medium temperature map,the X-ray surface brightness excess,and the X-ray peak offset together.

关键词： X rays:galaxies:clusters galaxies:clusters:intracluster medium galaxies:clusters:Abell 209

Melanocortin 3,5 receptors immunohistochemical expression in colonic mucosa of inflammatory bowel disease patients:A matter of disease activity?

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第9期30卷 1132-1142页

作者： Antonietta Gerarda Gravina Iacopo Panarese Maria Consiglia Trotta Michele D'Amico Raffaele Pellegrino Franca Ferraraccio Marilena Galdiero Roberto Alfano paolo Grieco Alessandro Federico Hepatogastroenterology Division Department of Precision MedicineUniversity of Campania Luigi VanvitelliNaples 80138Italy Pathology Division Department of Mental and Physical Health and Preventive MedicineUniversity of Campania Luigi VanvitelliNaples 80138Italy Department of experimental Medicine Division of PharmacologyUniversity of Campania Luigi VanvitelliNaples 80138Italy Department of Advanced Medical and Surgical Sciences(DAMSS) University of Campania Luigi VanvitelliNaples 80138Italy Department of Pharmacy University of Naples Federico IINaples 80131Italy

BACKGROUND Melanocortin 3 and 5 receptors(i.e.,MC3R and MC5R)belong to the melanocortin ***,data regarding their role in inflammatory bowel diseases(IBD)are currently *** This study aims to ascertain their expression profiles in the colonic mucosa of Crohn’s disease(CD)and ulcerative colitis(UC),aligning them with IBD disease endoscopic and histologic *** Colonic mucosal biopsies from CD/UC patients were sampled,and immunohisto-chemical analyses were conducted to evaluate the expression of MC3R and *** sampling was performed on both traits with endoscopic scores(Mayo endoscopic score and CD endoscopic index of severity)consistent with inflamed mucosa and not consistent with disease activity(i.e.,normal appearing mucosa).ReSULTS In both CD and UC inflamed mucosa,MC3R(CD:+7.7 fold vs normal mucosa,Pere significantly more expressed compared to normal *** MC3R and MC5R are expressed in the colon of IBD ***,expression may differ according to disease endoscopic activity,with a higher degree of expression in the traits affected by disease activity in both CD and UC,suggesting a potential use of these receptors in IBD pharmacology.

关键词： Melanocortin 3 receptor Melanocortin 5 receptor Ulcerative colitis Crohn's disease Inflammatory bowel disease

Nutrient restriction-activated Fra-2 promotes tumor progression via IGF1R in miR-15a downmodulated pancreatic ductal adenocarcinoma

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Signal Transduction and Targeted Therapy 2024年第3期9卷 1132-1146页

作者： Gian Luca Rampioni Vinciguerra Marina Capece Luca Reggiani Bonetti Giovanni Nigita Federica Calore Sydney Rentsch paolo Magistri Roberto Ballarin Fabrizio Di Benedetto Rosario Distefano Roberto Cirombella Andrea Vecchione Barbara Belletti Gustavo Baldassarre Francesca Lovat Carlo M.Croce Department of Cancer Biology and Genetics and Comprehensive Cancer Center The Ohio State UniversityColumbus 43210 OHUSA Department of Clinical and Molecular Medicine Faculty of Medicine and PsychologySant’Andrea HospitalUniversity of Rome“Sapienza”Rome 00189Italy Department of Diagnostic Clinic and Public Health MedicineUniversity of Modena and Reggio EmiliaModena 41100Italy Hepato-pancreato-biliary Surgery and Liver Transplantation Unit University of Modena and Reggio EmiliaModena 41100Italy Division of Molecular Oncology Centro di Riferimento Oncologico di Aviano(CRO)Istituto di Ricovero e Cura a Carattere Scientifico(IRCCS)National Cancer InstituteAviano 33081Italy

Pancreatic ductal adenocarcinoma(PDAC)is a lethal disease,characterized by an intense desmoplastic reaction that compresses blood vessels and limits nutrient *** aggressiveness largely relies on its extraordinary capability to thrive and progress in a challenging tumor *** of the onco-suppressor miR-15a has been extensively documented in ***,we identified the transcription factor Fos-related antigen-2(Fra-2)as a miR-15a target mediating the adaptive mechanism of PDAC to nutrient *** report that the IGF1 signaling pathway was enhanced in nutrient deprived PDAC cells and that Fra-2 and IGF1R were significantly overexpressed in miR-15a downmodulated PDAC ***,we discovered that miR-15a repressed IGF1R expression via Fra-2 *** miR-15a-low context,IGF1R hyperactivated mTOR,modulated the autophagic flux and sustained PDAC growth in nutrient *** a genetic mouse model,Mir15aKO PDAC showed Fra-2 and Igf1r upregulation and mTOR activation in response to diet ***,nutrient restriction improved the efficacy of IGF1R inhibition in a Fra-2 dependent ***,our results point to a crucial role of Fra-2 in the cellular stress response due to nutrient restriction typical of pancreatic cancer and support IGF1R as a promising and vulnerable target in miR-15a downmodulated PDAC.

关键词： IGF1R Fra miR