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Hepatocellular carcinoma risk after viral response in hepatitis C virus-advanced fibrosis: Who to screen and for how long?

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World Journal of Gastroenterology 2021年第40期27卷 6737-6749页

作者： Adriana Ahumada laura rayón Clara Usón Rafael Bañares Sonia Alonso Lopez Liver Unit Hospital General Universitario Gregorio MarañónMadrid 28007Spain Liver Unit Instituto de Investigación Sanitaria Gregorio Marañón(IiSGM)Madrid 28007Spain Medicine Universidad Complutense de MadridMadrid 28006Spain Centro de Investigación Biomédica En Red de Enfermedades Hepáticas y Digestivas(CIBERehd) Instituto de Salud Carlos IIIMadrid 28029Spain

Hepatitis C virus(HCV)chronic infection is associated with fibrosis progression,end-stage liver complications and *** surprisingly,HCV infection is a leading cause of liver-related morbidity and mortality *** sustained virological response(SVR),the risk of developing hepatocellular carcinoma is not completely eliminated in patients with established cirrhosis or with advanced ***,lifelong surveillance is currently *** strategy is likely not universally cost-effective and harmless,considering that not all patients with advanced fibrosis have the same risk of developing *** related to the severity of liver disease and its potential to improve after SVR,the molecular and epigenetic changes that occur during infection and other associated comorbidities might account for different risk levels and are likely essential for identifying patients who would benefit from screening programs after *** to develop predictive models and risk calculators,biomarkers and genetic panels and even deep learning models to estimate the individual risk of HCC have been made in the direct-acting antiviral agents era,when thousands of patients with advanced fibrosis and cirrhosis have reached *** tools could help to identify patients with very low HCC risk in whom surveillance might not be *** this review,factors affecting the probability of HCC development after SVR,the benefits and risks of surveillance,suggested strategies to estimate individualized HCC risk and the current evidence to recommend lifelong surveillance are discussed.

关键词： Hepatitis C virus Hepatocellular carcinoma Liver fibrosis Surveillance Sustained virologic response Epigenetic changes Predictive models Cost-effectiveness

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Hierarchical state-abstracted and socially augmented Q-Learning for reducing complexity in agent-based learning

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控制理论与应用（英文版） 2011年第3期9卷 440-450页

作者： laura ray Thayer School of Engineering Dartmouth College

A primary challenge of agent-based policy learning in complex and uncertain environments is escalating computational complexity with the size of the task space(action choices and world states) and the number of ***,there is ample evidence in the natural world that high-functioning social mammals learn to solve complex problems with ease,both individually and *** ability to solve computationally intractable problems stems from both brain circuits for hierarchical representation of state and action spaces and learned policies as well as constraints imposed by social *** biologically derived mechanisms for state representation and mammalian social intelligence,we constrain state-action choices in reinforcement learning in order to improve learning *** results bound the reduction in computational complexity due to stateion,hierarchical representation,and socially constrained action selection in agent-based learning problems that can be described as variants of Markov decision *** of two task domains,single-robot herding and multirobot foraging,shows that theoretical bounds hold and that acceptable policies emerge,which reduce task completion time,computational cost,and/or memory resources compared to learning without hierarchical representations and with no social knowledge.

关键词： Decentralized Markov decision process Reinforcement learning Multiagent systems

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Analysis of cerium substitution in Co-Sr based spinel ferrites for high frequency application

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Journal of Rare Earths 2024年第9期42卷 1755-1763,I0005页

作者： laura Khudaysh Inas A.Ahmed Syeda Rabia Ejaz Sajjad Ahmad Khan Yasir A.Haleem Mohamed M.Ibrahim Mahmood Ali Hafiz Muhammad Tahir Farid Zeinhom M.El-Bahy Department of Physics Faculty of ScienceJazan UniversityJazan45142Saudi Arabia Department of Chemistry Faculty of ScienceKing Khalid UniversityAbha62224Saudi Arabia Department of Physics The Government Sadiq College Women UniversityBahawalpur63100Pakistan Institute of Physics Khwaja Fareed University of Engineering and Information TechnologyRahim Yar Khan64200Pakistan Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Centre of Excellence in Solid State Physics University of the PunjabLahorePakistan Department of Physics Government CollegeTaunsa Sharif32200Pakistan Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr City11884CairoEgypt

Spinel ferrites exhibit exceptional magnetic properties,making them a distinctive class of magnetic *** sol-gel technique was utilized for the synthesis of spinel ferrites with the chemical formula Co_(0.6)Sr_(0.4)Ce_(x)Fe_(2-x)O_(4). Following that,a comprehensive X-ray diffraction analysis unveiled the crystalline cubic structure of the synthesized *** the utilization of the M-H loop approach,the ferromagnetic attributes of ferrites were assessed,and the assimilation of rare earth elements led to substantial enhancements in saturation magnetization,remanence,and *** ferrites with a high concentration of rare earth elements have improved direct current resistivity and activation *** logarithm of a material's resistance increased from 5.29 to 8.12 Ω·cm as cerium is *** a change in the amount of cerium,the activation energy goes up from 0.19 to *** changing the frequency from 5.5 to 9.5 GHz,the dielectric characteristics were *** the frequency goes up,the dielectric constant goes *** ferrites that have been made better in every way can be used in high-frequency applications.

关键词： Activation energy DC electrical resistance Remanence magnetization Cobalt strontium spinel ferrites High frequency application Rare earths

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Observation of a single protein by ultrafast X-ray diffraction

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Light(Science & Applications) 2024年第1期13卷 80-90页

作者： Tomas Ekeberg Dameli Assalauova Johan Bielecki Rebecca Boll Benedikt J.Daurer Lutz A.Eichacker Linda E.Franken Davide E.Galli Luca Gelisio Lars Gumprecht laura H.Gunn Janos Hajdu Robert Hartmann Dirk Hasse Alexandr Ignatenko Jayanath Koliyadu Olena Kulyk Ruslan Kurta Markus Kuster Wolfgang Lugmayr Jannik Lübke Adrian P.Mancuso Tommaso Mazza Carl nettelblad Yevheniy Ovcharenko Daniel E.Rivas Max Rose Amit K.Samanta Philipp Schmidt Egor Sobolev nicusor Timneanu Sergey Usenko Daniel Westphal Tamme Wollweber Lena Worbs Paul Lourdu Xavier Hazem Yousef Kartik Ayyer Henry n.Chapman Jonas A.Sellberg Carolin Seuring Ivan A.Vartanyants Jochen Küpper Michael Meyer Filipe R.n.C.Maia Laboratory of Molecular Biophysics Department of Cell and Molecular BiologyUppsala UniversityHusargatan 3(Box 596)SE-75124 UppsalaSweden Deutsches Electronen-Synchrotron DESY Notkestrasse 8522607 HamburgGermany European XFEL Holzkoppel 422869 SchenefeldGermany Diamond Light Source Harwell Science&Innovation CampusDidcot OX110DEUK University of Stavanger Centre Organelle ResearchRichard-Johnsensgate 44021 StavangerNorway Leibniz Institute for Experimental Virology(HPI) Centre for Structural Systems BiologyNotkestraße 8522607 HamburgGermany Dipartimento di Fisica“Aldo Pontremoli” Universitàdegli Studi di Milanovia Celoria 1620133 MilanoItaly Center for Free-Electron Laser Science DESY22607 HamburgGermany Plant Biology Section School of Integrative Plant ScienceCornell UniversityIthacaNY 14853USA PnSensor GmbH Otto-Hahn-Ring 6D-81739 MünchenGermany Biomedical and X-ray Physics Department of Applied PhysicsAlbaNova University CenterKTH Royal Institute of TechnologySE-10691 StockholmSweden ELI Beamlines/IoP Institute of Physics AS CR v.v.i.Na Slovance 218221 Prague 8Czech Republic Multi-User CryoEM Facility Centre for Structural Systems BiologyNotkestr.8522607 HamburgGermany University Medical Center Hamburg-Eppendorf(UKE) Martinistrasse 5220246 HamburgGermany The Hamburg Center for Ultrafast Imaging Universität HamburgLuruper Chaussee 14922761 HamburgGermany Department of Physics Universität HamburgLuruper Chaussee 14922761 HamburgGermany Department of Chemistry and Physics La Trobe Institute for Molecular ScienceLa Trobe UniversityMelbourneVIC 3086Australia Division of Scientific Computing Science for Life LaboratoryDepartment of Information TechnologyUppsala UniversityBox 337SE-75105 UppsalaSweden European Molecular Biology Laboratory c/o DESYNotkestrasse 8522607 HamburgGermany Department of Physics and Astronomy Uppsala UniversityBox 516SE-75120 UppsalaSweden Max Planck Institute for the Structure and Dynamics of Matter Luruper Chaussee 14922761 HamburgGe

The idea of using ultrashort X-ray pulses to obtain images of single proteins frozen in time has fascinated and inspired *** was one of the arguments for building X-ray free-electron *** to theory,the extremely intense pulses provide sufficient signal to dispense with using crystals as an amplifier,and the ultrashort pulse duration permits capturing the diffraction data before the sample inevitably *** was first demonstrated on biological samples a decade ago on the giant *** then,a large collaboration has been pushing the limit of the smallest sample that can be *** ability to capture snapshots on the timescale of atomic vibrations,while keeping the sample at room temperature,may allow probing the entire conformational phase space of *** we show the first observation of an X-ray diffraction pattern from a single protein,that of Escherichia coli GroEL which at 14 nm in diameter is the smallest biological sample ever imaged by X-rays,and demonstrate that the concept of diffraction before destruction extends to single *** the pattern,it is possible to determine the approximate orientation of the *** experiment demonstrates the feasibility of ultrafast imaging of single proteins,opening the way to single-molecule time-resolved studies on the femtosecond timescale.

关键词： smallest intense ultrafast

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Decoupling the adsorption mechanisms of arsenate at molecular level on modified cube-shaped sponge loaded superparamagnetic iron oxide nanoparticles

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Journal of Environmental Sciences 2022年第11期34卷 1-12页

作者： Xiang-Yang Lou Roberto Boada Veronica Verdugo laura Simonelli Gustavo Pérez Manuel Valiente GTS-UAB Research Group Department of ChemistryFacultat de CiènciesUniversitat Autonoma de Barcelona08193 BellaterraSpain ALBA Synchrotron Carrer de la llum 2-26Cerdanyola del Valles08290 BarcelonaSpain Centro de Excelencia en nanotecnologia Leitat ChileSantiago 7500724Chile

In this study, a commercial cube-shaped open-celled cellulose sponge adsorbent was modified by in-situ co-precipitation of superparamagnetic iron oxide nanoparticles(SPIOn) and used to remove As(V) from aqueous solutions. Fe K-edge X-ray absorption spectroscopy(XAS) and TEM identified maghemite as the main iron phase of the SPIOn nanoparticles with an average size 13 nm. Batch adsorption experiments at 800 mg/L showed a 63% increase of adsorption capacity when loading 2.6 wt.% mass fraction of SPIOn in the *** determination of the adsorption thermodynamic parameters indicated that the As(V) adsorption on the composite material is a spontaneous and exothermic *** K-edge XAS results confirmed that the adsorption enhancement on the composite can be attributed to the nanoparticles loaded. In addition, adsorbed As(V) did not get reduced to more toxic As(Ⅲ) and formed a binuclear corner-sharing complex with SPIOn. The advantageous cube-shape of the sponge-loaded SPIOn composite together with its high affinity and good adsorption capacity for As(V), good regeneration capability and the enhanceddiffusion attributed to its open-celled structure make this adsorbent a good candidate for industrial applications.

关键词： Adsorption Cube composite adsorbent Arsenate removal Regeneration X-ray absorption spectroscopy

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Diagnostic procedures for submucosal tumors in the gastrointestinal tract

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World Journal of Gastroenterology 2007年第24期13卷 3301-3310页

作者： laura Graves Ponsaing Katalin Kiss Annika Loft Lise Ingemann Jensen Mark Berner Hansen Department of Surgical Gastroenterology K Bispebjerg University Hospital of Copenhagen Denmark Department of Pathology Herlev University Hospital Gentofte Denmark Department of nuclear Medicine CopenhagenUniversity Hospital Rigshospitalet Denmark Department of Radiology Bispebjerg University Hospital of Copenhagen Denmark

This review is part one of three, which will present an update on diagnostic procedures for gastrointestinal (GI) submucosal tumors (SMTs). Part two identifies the classification and part three the therapeutic methods regarding GI SMTs. Submucosal tumors are typically asymptomatic and therefore encountered incidentally. Advances in diagnostic tools for gastrointestinal submucosal tumors have emerged over the past decade. The aim of this paper is to provide the readers with guidelines for the use of diagnostic procedures, when a submucosal tumor is suspected. Literature searches were performed to find information on diagnostics for gastrointestinal submucosal tumors. Based on the searches, the optimal diagnostic procedures and specific features of the submucosal tumors could be outlined. Standard endoscppy, capsule endoscopy and push-and-pull enteroscopy (PPE) together with barium contrast X-ray do not alone provide sufficient information, when examining submucosal tumors. Endoscopic ultrasound (EUS), computed tomography (CT), magnetic resonance imaging (MRI) and fluorodeoxyglucose-labeled positron emission tomography (FDG-PET) are recommended as supplementary tools.

关键词： Submucosal tumor Diagnosis Endoscopy Endoscopic ultrasonography Computed tomography Magnetic resonance imaging Positron emission tomography Capsule endoscopy Push-and-pull enteroscopy Ponsaing LG, Kiss K, Loft A, Jensen LI, Hansen MB.

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Human bocavirus in children hospitalized for acute respiratory tract infection in Rome

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World Journal of Pediatrics 2020年第3期16卷 293-298页

作者： laura Petrarca Raffaella nenna Antonella Frassanito Alessandra Pierangeli Greta Di Mattia Carolina Scagnolari Fabio Midulla Maternal-Infantile and Urological Science Department "Sapienza"University of RomeRomeItaly Virology Laboratory Department of Molecular Medicine"Sapienza"University of RomeRomeItaly

Background The role of human bocavirus (HBoV) as a respiratory pathogen has not been fulfilled *** aimed to describe clinical and serological characteristics of children with HBoV hospitalized for acute respiratory tract infection and to evaluate whether differences occur between HBoV alone and in *** We retrospectively reviewed data from 60 children (median age of 6.2 months,range 0.6-70.9) hospitalized for acute respiratory symptoms,with HBoV detected from a respiratory sample,using a reverse transcriptase-PCR for 14 respiratory viruses (including respiratory syncytial virus (RSV),influenza virus A and B,human coronavirus OC43,229E,nL-63 and HUK1,adenovirus,rhinovirus,parainfluenza virus 1-3,and human metapneumovirus).Results HBoV was detected alone in 29 (48.3%) patients,while in co-infection with other viruses in 31 patients (51.7%),with a peak between December and *** the 60 patients,34 were bronchiolitis,19 wheezing,3 pneumonia,2 upper respiratory tract infection,and 2 whooping *** children (11.6%) required admission to the paediatric intensive care unit (PICU) for respiratory *** differences was observed in age,family history for atopy and/or asthma,clinical presentations,chest X-ray,or laboratory findings in children with HBoV alone *** viral *** was the most frequently co-detected virus (61.3%).When compared with HBoV detection alone,the co-detection of RSV and HBoV was associated with male sex (P=0.013),younger age (P=0.01),and lower blood neutrophil count (P=0.032).Conclusions HBoV can be detected alone and in co-infection respiratory samples of children with an acute respiratory tract infection.A cause-effect relationship between HBoV and respiratory infection is not clear,so further studies are needed to clarify this point.

关键词： Human bocavirus Pediatrics Respiratory tract infection Viral infection

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Field study of a soft X-ray aerosol neutralizer combined with electrostatic classifiers for nanoparticle size distribution measurements

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Particuology 2018年第2期16卷 99-106页

作者： Alessia nicosia laura Manodori Arianna Trentini Isabella Ricciardelli Dimitri Bacco Vanes Poluzzi Lorenza Di Matteo Franco Belosi Institute of Atmospheric Sciences and Climate (ISAC)-CnR Bologna Italy Department of Physics and Earth Sciences University of Ferrara 44122 Ferrara Italy ECSIn - European Center for the Sustainable Impact ofnanotechnology Veneto Nanotech Scpa Rovigo Italy d Regional Agency for Prevention Environment and Energy of Emilia-Romagna (ARPAE) Bologna Italy Regional Agency for Prevention Environment and Energy of Emilia-Romagna (ARPAE) Bologna Italy University of Eastern Piedmont "A. Avogadro" Department of Science and Technology Innovation Alessandria Italy

Most conventional aerosol neutralizers are based on radioactive sources, which are controlled by strict regulations restricting their handling, transport, and storage. The TSI 3087 soft X-ray （SXR） neutralizer circumvents these legal restrictions. The aim of the present work is to compare the performance of a standalone SXR aerosol neutralizer with that of conventional radioactive aerosol neutralizers based on 85Kr （TSI 3077） and 241Am （Grimm 5522） by performing field tests in a real environmental scenario. The results obtained when the SXR neutralizer was connected to a mobility particle sizer spectrometer （MPS）, different from the device suggested by the manufacturer, were comparable with those obtained with the use of radioactive aerosol neutralizers. In changing the neutralizer, the particle number concentrations, measured with the MPS connected to the SXR neutralizer, almost remained within the 10% uncertainty bounds for the particle size interval 10-300 nm, when diffusion losses inside the SXR tube were considered. Based on our comparisons, the SXR neutralizer can be regarded as a standalone instrument that could solve the problems associated with legal restrictions on radioactive neutralizers and fulfil the need for a portable instrument for different field test purposes.

关键词： Aerosol neutralizer Soft X-ray non-radioactive charger Mobility particle sizer spectrometer Particle size distribution Diffusion losses

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Characterisation of Photocathodes Based on Pb Thin Film Deposited by UV Pulsed Laser Ablation

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Journal of Materials Science & Technology 2014年第1期30卷 37-40页

作者： Francisco Gontad Antonella Lorusso Giancarlo Gatti Massimo Ferrario laura Gioia Passione Luana Persano nicola Lovergine Alessio Perrone Istituto nazionale di Fisica nucleare e Università del Salento Università del Salento Dipartimento di Matematica e Fisica "E.De Giorgi" Laboratori nazionali di Frascati Istituto Nazionale di Fisica Nucleare Center for Biomolecular nanotechnologies Istituto Italiano di Tecnologia Dipartimento di Ingegneria dell'Innovazione Università del Salento national nanotechnology Laboratory(nnL)

This work deals with the deposition of lead （Pb） thin films by the UV pulsed laser ablation technique, for their further use as photocathode devices in superconducting radio frequency guns. Scanning electron microscopy and atomic force microscopy analyses were performed to study the morphological features of Pb thin films deposited on Si （100） and nb substrates. The films showed a granular structure with a nearly fully covered surface only for that one deposited on nb substrate. X-ray diffraction measurements indicate the growth of polycrystalline Pb thin films with a preferential orientation along （111） planes. Results of the photoemission performance of Pb thin film deposited on nb substrate showed a very encouraging average value of quantum efficiency of 6 x 10-5 through a single-photon absorption process, promoting further studies in the realisation of Pb photocathodes by this technique.

关键词： Pulsed laser deposition Lead thin film Metallic photocathodes Quantum efficiency

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Pneumatosis cystoides intestinalis

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World Journal of Gastroenterology 2011年第44期17卷 4932-4936页

作者： Francesco Azzaroli laura Turco Liza Ceroni Stefania Sartoni Galloni Federica Buonfiglioli Claudio Calvanese Giuseppe Mazzella Department of Clinical Medicine Division of GastroenterologyS.Orsola-Malpighi HospitalUniversity of Bologna Department of Emergency General Surgery and TransplantationS.Orsola-Malpighi HospitalUniversity of Bologna

Pneumatosis cystoides intestinalis(PCI) is a rare condition that may be associated with a variety of *** presenting clinical picture may be very heterogeneous and represent a challenge for the *** the present paper we describe both a common and an uncommon clinical presentation of PCI and review the pertaining *** cases confirm that,apart from asymptomatic cases,the clinical presentation of PCI may be widely different and suggest that a new onset of stipsis might be the presenting *** might be suggested by a simple X-ray of the digestive tract showing a change in the characteristics of the intestinal wall in two-thirds of these ***,one third of the patients do not have a suggestive X-ray and require a computed tomography(CT) scan/nuclear magnetic resonance that may reveal a thickened bowel wall containing gas to confirm the diagnosis and distinguish PCI from intraluminal air or submucosal *** also allows the detection of additional findings that may suggest an underlying,potentially worrisome cause of PCI such as bowel wall thickening,altered contrast mucosal enhancement,dilated bowel,soft tissue stranding,ascites and the presence of portal *** results also point out that clinicians and endoscopists should be aware of the possible presentations of PCI in order to correctly manage the patients affected with this disease and avoid unnecessary *** increasing number of colonoscopies performed for colon cancer screening makes PCI more frequently casually encountered and/or provoked,therefore the possible endoscopic appearances of this disease should be well known by endoscopists.

关键词： Pneumatosis cystoides intestinalis Pneumoperitoneum Treatment Hyperbaric oxygen Endoscopy

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