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Spectral and fragility evaluations of retrofitted structures through strength reduction and enhanced damping

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Earthquake Engineering and Engineering Vibration 2009年第1期8卷 115-125页

作者： Gian Paolo Cimellaro Hwasung Roh Alessandro De stefano Department of Structural & Geotechnical Engineering (DISTR) Polytechnic of Turin Turin Italy Department of Civil Structural & Environmental Engineering University at Buffalo The State University of New York Buffalo USA

A retrofit procedure for existing buildings called the ＂weakening and damping technique＂（WED） is presented in this paper. Weakening of structures can limit the maximum response accelerations during severe ground motions, but leads to an increase in the displacements or inter-story drifts. Added damping by using viscous dampers, on the other hand, reduces the inter-story drifts and has no significant effect on total accelerations, when structures behave inelastically. The weakening and damping technique addresses the two main causes for both structural and nonstructural damage in structures. The weakening retrofit is particularly suitable for structures that have overstressed components and weak brittle components. In this paper, the advantages of the WeD are verified by nonlinear dynamic analysis and simplified spectral approach that has been modified to fit structures with additional damping devices. A hospital structure located in the San Fernando Valley in California is selected as a case study. The results from both analyses show that the retrofit solution is feasible to reduce both structural acceleration and displacement. A sensitivity analysis is also carried out to evaluate the effectiveness of the retrofitting method using different combinations of performance thresholds in accelerations and displacements through fragility analysis.

关键词： weakening damping retrofit inelastic spectral response fragility analysis nonlinear dynamic analysis

Effects of liquid feed rate and impeller rotation speed on heat transfer in a mechanically fluidized reactor

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Particuology 2018年第4期16卷 25-32页

作者： Dhiraj Kankariya Cedric Briens Dominic Pjontek stefano Tacchino Department of Chemical and Biochemical Engineering University of Western Ontario London Ontario N6A 5B9 Canada

A mechanically fluidized reactor （MFR） is a novel and compact reactor used for biomass pyrolysis. Endothermic biomass pyrolysis requires heat provided from the wall of the MFR. Meanwhile, mixing with a vertical stirrer helps achieve effective heat transfer from the wall to the bed. Here, the heat trans- fer characteristics between the wall of a 1.0-L MFR and its bed of mechanically fluidized sand particles were studied. An induction heating system was used to heat the wall, while a vertical blade stirrer was used for mixing. Heat transfer measurements were carried out using silica sand particles, having three average Sauter mean diameters： 190, 300, and 600 p.m. The overall wall-to-bed heat transfer coeffi- cients were estimated using temperature measurements taken during continuous injection of water onto the fluidized bed. The overall heat transfer coefficient for bed temperatures of 500-700℃ increased as particle size increased or superficial velocity of the vaporized liquid increased. Effect of impeller rotation speed also was investigated. Typically, the overall heat transfer coefficient increased as rotation speed increased. The wall-to-bed heat transfer coefficients obtained in this study are comparable to estimates from traditional bubbling fluidized beds, even at vapor velocities below the minimum fluidization veloccity.

关键词： Mechanical fluidization Induction heating Impeller rotation Heat transfer Particle size

Selection criteria in resectable pancreatic cancer: A biological and morphological approach

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World Journal of Gastroenterology 2014年第32期20卷 11210-11215页

作者： Domenico Tamburrino stefano Partelli stefano Crippa Alberto Manzoni Angela Maurizi Massimo Falconi Pancreatic Surgery Unit Department of Surgery Polytechnic University of Marche Region

Pancreatic ductal adenocarcinoma(PDA) remains one of the most aggressive tumors with a low rate of survival. Surgery is the only curative treatment for PDA, although only 20% of patients are resectable at diagnosis. During the last decade there was an improvement in survival in patients affected by PDA, possibly explained by the advances in cancer therapy and by improve patient selection by pancreatic surgeons. It is necessary to select patients not only on the basis of surgical resectability, but also on the basis of the biological nature of the tumor. Specific preoperative criteria can be identified in order to select patients who will benefit from surgical resection. Duration of symptoms and level of carbohydrate antigen 19.9 in resectable disease should be considered to avoid R1 resection and early relapse. Radiological assessment can help surgeons to distinguish resectable disease from borderline resectable disease and locally advanced pancreatic cancer. Better patient selection can increase survival rate and neoadjuvant treatment can help surgeons select patients who will benefit from surgery.

关键词： Pancreatic ductal adenocarcinoma Pancreatic cancer Borderline resectable pancreatic cancer Pancreatic surgery Pancreatic cancer staging

Bile acid activated receptors: Integrating immune and metabolic regulation in non-alcoholic fatty liver disease

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Liver Research 2021年第3期5卷 119-141页

作者： Michele Biagioli stefano Fiorucci Department of Medicine and Surgery University of PerugiaPerugiaItaly

Bile acids are a family of atypical steroids generated at the interface of liver-intestinal microbiota acting on a ubiquitously expressed family of membrane and nuclear receptors known as bile acid activated *** two best characterized receptors of this family are the nuclear receptor,farnesoid X re-ceptor(FXR)and the G protein-coupled receptor,G protein-coupled bile acid receptor 1(GPBAR1).FXR and GPBAR1 regulate major aspects of lipid and glucose metabolism,energy balance,autophagy and immunity and have emerged as potential pharmaceutical targets for the treatment of metabolic and inflammatory *** trials in non-alcoholic fatty liver disease(NAFLD),however,have shown that selective FXR agonists cause side effects while their efficacy is *** FXR and GPBAR1 exert additive effects,dual FXR/GPBAR1 ligands have been developed for the treatment of metabolic disorders and are currently advanced to clinical ***,we will review the role of FXR and GPBAR1 agonism in NAFLD and how the two receptors could be exploited to target multiple components of the disease.

关键词： Bile acid Farnesoid X receptor(FXR) G protein-coupled bile acid receptor 1(GPBAR1) Immunity Lipid metabolism Non-alcoholic fatty liver disease(NAFLD) Non-alcoholic steatohepatitis(NASH)

Pyrolysis of WEEE plastics using catalysts produced from fly ash of coal gasification

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Frontiers of Environmental Science & Engineering 2017年第5期11卷 113-123页

作者： Marika Benedetti Lorenzo Cafiero Doina De Angelis Alessandro Dell'Era Mauro Pasquali stefano Stendardo Riceardo Tuffi stefano Veechio Ciprioti Department for Sustainability ENEA - Casaccia Research Center Via Anguillarese 301 S. Maria di Galeria Rome Italy Department of SBAI Sapienza University of Rome Via del Castro Laurenziano 7 00161 Rome Italy Department of Energy Technologies ENEA Casaccia Research Center Via Anguillarese 301 S. Mafia di Galeria Rome Italy

Catalytic pyrolysis of thermoplastics extracted from waste electrical and electronic equipment （WEEE） was investigated using various fly ash-derived catalysts. The catalysts were prepared from fly ash by a simple method that basically includes a mechanical treatment followed by an acid or a basic activation. The synthesized catalysts were characterized using various analytical techniques. The results showed that not treated fly ash （FA） is characterized by good crystallinity, which in turn is lowered by mechanical and chemical treatment （fly ash after mechanical and acid activation, FAMA） and suppressed almost entirely down to let fly ash become completely amorphous （fly ash al^er mechanical and basic activation FAMB）. Simultaneously, the surface area resulted increased. Subsequently, FA, FAMB and FAMA were used in the pyrolysis of a WEEE plastic sample at 400~C and their performance were compared with thermal pyrolysis at the same temperature. The catalysts principally improve the light oil yield： from 59 wt.% with thermal pyrolysis to 83 wt.% using FAMB. The formation of styrene in the oil is also increased： from 243 mg/g with thermal pyrolysis to 453 mg/g using FAMB. As a result, FAMB proved to be the best catalyst, thus producing also the lowest and the highest amount of char and gas, respectively.

关键词： Waste electrical and electronic equipment(WEEE) plastic mixture Pyrolysis Catalyst Fly asla Oil

Focal liver lesions detection and characterization: The advantages of gadoxetic acid-enhanced liver MRI

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World Journal of Hepatology 2014年第7期6卷 477-485页

作者： stefano Palmucci Radiodiagnostic and Radiotherapy Unit University Hospital "Policlinico-Vittorio Emanuele" 95123 Catania Italy

Since its clinical introduction, several studies in literature have investigated gadolinium ethoxybenzhyl diethylenetriaminepentaacetic acid or gadoxetic acid(Gd-EOB-DTPA) properties. Following contrast injection, it provides dynamic vascular phases(arterial, portal and equilibrium phases) and hepatobiliary phase, the latter due to its uptake by functional hepatocytes. The main advantages of Gd-EOB-DTPA of focal liver lesion detection and characterization are discussed in this paper. Namely, we focus on the possibility of distinguishing focal nodular hyperplasia(FNH) from hepatic adenoma(HA), the identification of early hepatocellular carcinoma(HCC) and the pre-operative assessment of metastasis in liver parenchyma. Regarding the differentiation between FNH and HA, adenoma typically appears hypointense in hepatobiliary phase, whereas FNH is isointense or hyperintense to the surrounding hepatic parenchyma. As for the identification of early HCCs, many papers recently published in literature have emphasized the contribution of hepatobiliary phase in the characterization of nodules without a typical hallmark of HCC. Atypical nodules(no hypervascularizaton observed on arterial phase and/or no hypovascular appearance on portal phase) with low signal intensity in the hepatobiliary phase, have a high probability of malignancy. Finally, regarding the evaluation of focal hepatic metastases, magnetic resonance pre-operative assessment using gadoxetic acid allows for more accurate diagnosis.

关键词： Magnetic resonance imaging Liver Image enhancement Gadolinium diethylenetriaminepentaacetic acid Carcinoma Hepatocellular

Beyond KRAS:Predictive factors of the efficacy of anti-EGFR monoclonal antibodies in the treatment of metastatic colorectal cancer

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World Journal of Gastroenterology 2014年第29期20卷 9732-9743页

作者： Alfonso De stefano Chiara Carlomagno Department of Clinical Medicine and Surgery University of Naples Federico Ⅱ

Systematic analysis of the epidermal growth factor receptor(EGFR)pathway revealed that biomarkers could be used to predict the response to and outcome of antiEGFR therapies in patients affected by metastatic colorectal *** have conducted a review on the most recent findings and advances on this *** this aim,we searched the PubMed database for articles devoted to predictive and prognostic biomarkers for patients administered cetuximab-and panitumumab-based *** we review the state of the art and the controversies about the molecular factors known to be predictors of the efficacy of anti-EGFR therapy,namely,KRAS,BRAF,NRAS,PI3KCA and PTEN,and we discuss their prognostic value in colorectal cancer patients.

关键词： KRAS Anti-epidermal growth factor receptor Metastatic colorectal cancer Biomarkers

Bidirectional Electron Transfer in the Reaction Centre of Photosystem I

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Journal of Integrative Plant Biology 2010年第8期52卷 735-749页

作者： stefano Santabarbara Luca Galuppini Anna Paola Casazza Istituto di Biofisica Consiglio Nazionale delle Ricerche Department of Physics University of Strathclyde Centre for Fundamental Research in Photosynthesis The Burroughs Consiglio Nazionale delle Ricerche Istituto di Biologia e Biotecnologia Agraria

In the past decade light-induced electron transfer reactions in photosystem I have been the subject of intensive investigations that have led to the elucidation of some unique characteristics, the most striking of which is the existence of two parallel, functional, redox active cofactors chains. This process is generally referred to as bidirectional electron transfer. Here we present a review of the principal evidences that have led to the uncovering of bidirectionality in the reaction centre of photosystem I. A special focus is dedicated to the results obtained combining time-resolved spectroscopic techniques, either difference absorption or electron paramagnetic resonance, with molecular genetics, which allows, through modification of the binding of redox active cofactors with the reaction centre subunits, an effect on their physical-chemical properties.

关键词： Bidirectional Electron Transfer in the Reaction Centre of Photosystem I PsaA

Role of amygdala in mediating sexual and emotional behavior via coupled nitric oxide release

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Acta Pharmacologica Sinica 2005年第4期26卷 389-395页

作者： Elliott SALAMON Tobias ESCH George B stefano Neuroscience Research Institute State University of New York College at Old Westbury Old Westbury New York 11568 USA Neuroscience Research Institute State University of New York College at Old Westbury Old Westbury New York 11568 USA Charit University Medicine Berlin Institute for General Practice and Family Medicine Schumannstrasse 10117 Berlin Germany Neuroscience Research Institute State University of New York College at Old Westbury Old Westbury New York 11568 USA

Although the anatomical configuration of the amygdala has been studied a greatdeal,very little research has been conducted on understanding the precise mecha-nism by which this emotional regulatory center exerts its control on emotional andsexual *** applying research methodology from the Neuroscience Re-search Institute,State University of New York,College at Old Westbury,we in-tended to demonstrate that much of the mediated effects of the amygdala,specifi-cally the regulation of the male and female sexual response cycles,as well asrelated emotional considerations,exert their effects coupled to nitric oxide (NO)***,by using current anatomical and histological data,wedemonstrated that amygdalar tissue rich in endocannabinoid and opiate,as wellas catecholamine,receptors could exert its neurochemical effects within an NO-mediated *** paradigm,together with the existence of estrogen andandrogen signaling within the amygdala,further lends credence to our *** begin with a brief anatomical and functional review of amygdalarfunction,and then proceed to demonstrate its relationship with NO.

关键词： amygdala sex nitric oxide morphine emotion