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Studies of Spectroscopic Ellipsometry in Cd1-xMnxTe/CdTe Superlattices

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Chinese Physics Letters 2006年第1期23卷 207-210页

作者：陈辰嘉王学忠 vittorio BELLANI Angiolino STELLA School of Physics Peking University Beijing 100871 Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia (CNISM) and Dipartimento di Fisica 'A. Volta' Universita degli Studi di Pavia 27100 Pavia Italy

Cd1-xMnxTe/CdTe superlattices and thin films were grown by molecular beam epitaxy on GaAs （001） substrates. Spectroscopic ellipsometry measurements were performed on Cd1-x Mnx Te/ CdTe superlattices with compositions x = 0.4, 0.8, and Cd1-xMnx Te thin films with x = 0.2, 0.4, 0.6 at room temperature in the photon energy range 1.4-5 eV. In superlattices the pseudodielectric functions measured by ellipsometry show specific features related to the exciton transition between quantized interbands. The exciton transitions related to the heavy holes of 11 H, 22H, and 33H are observed and identified. In thin films spectroscopic ellipsometry allows the clear identification of the energy gap Eo. Additionally, critical point transitions are observable in both the spectra of the superlattices and films. Photoreflectance spectra were also performed at room temperature in order to compare with our ellipsometry results. After taking into account the strain-induced and quantum confinement effects, the theoretical calculations are in good agreement with our experimental spectra. Ellipsometry appears to be a suited technique to monitor the MBE growth, ultimately also in situ, of diluted magnetic low-dimensional systems.

关键词： INTERBAND-TRANSITIONS

Mesenchymal stem cells in neurodegenerative diseases: Opinion review on ethical dilemmas

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World Journal of Stem Cells 2020年第3期12卷 168-177页

作者： Matteo Scopetti Alessandro Santurro vittorio Gatto Raffaele La Russa Federico Manetti Stefano D’Errico Paola Frati vittorio Fineschi Department of Anatomical HistologicalForensic and Orthopaedic SciencesSapienza University of RomeRome 00185Italy Istituto di Ricovero e Cura a Carattere Scientifico(IRCCS)Neuromed Sapienza University of RomaPozzilli 86077Italy UOC Risk Management Quality and AccreditationSant'Andrea University Hospital of RomeRome 00189Italy

The treatment of neurodegenerative diseases presents a growing need for innovation in relation to recent evidence in the field of reconstructive therapy using stem cells. Understanding the molecular mechanisms underlying neurodegenerative disorders, and the advent of methods able to induce neuronal stem cell differentiation allowed to develop innovative therapeutic approaches offering the prospect of healthy and perfectly functional cell transplants, able to replace the sick ones. Hence the importance of deepening the state of the art regarding the clinical applications of advanced cell therapy products for the regeneration of nerve tissue. Besides representing a promising area of tissue transplant surgery and a great achievement in the field of neurodegenerative disease, stem cell research presents certain critical issues that need to be carefully examined from the ethical perspective. In fact, a subject so complex and not entirely explored requires a detailed scientific and ethical evaluation aimed at avoiding improper and ineffective use, rather than incorrect indications, technical inadequacies, and incongruous expectations. In fact, the clinical usefulness of stem cells will only be certain if able to provide the patient with safe, long-term and substantially more effective strategies than any other treatment *** present paper provides an ethical assessment of tissue regeneration through mesenchymal stem cells in neurodegenerative diseases with the aim to rule out the fundamental issues related to research and clinical translation.

关键词： Mesenchymal stem cells Neurodegenerative diseases Stem cell research Stem cell therapy Ethical principles Patient safety

Direct Simulation of Charge Transport in Graphene Nanoribbons

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Communications in Computational Physics 2022年第2期31卷 449-494页

作者： Giovanni Nastasi V.Dario Camiola vittorio Romano Universita degli Studi di Catania Dipartimento di Matematica e InformaticaViale Andrea Doria 695125 CataniaItaly

Graphene nanoribbons are considered as one of the most promising ways to design electron devices where the active area is made of *** fact,graphene nanoribbons present a gap between the valence and the conduction bands as in standard semiconductors such as Si or GaAs,at variancewith large area graphenewhich is gapless,a feature that hampers a good performance of graphene field effect *** use graphene nanoribbons as a semiconductor,an accurate analysis of their electron properties is ***,electron transport in graphene nanoribbons is investigated by solving the semiclassical Boltzmann equation with a discontinuous Galerkin *** the electron-phonon scattering mechanisms are *** adopted energy band structure is that devised in[1]while according to[2]the edge effects are described as an additional scattering stemming from the Berry-Mondragon model which is valid in presence of edge *** this approach a spacial 1D transport problem has been solved,even if it remains two dimensional in the wavevector space.A degradation of charge velocities,and consequently of the mobilities,is found by reducing the nanoribbon width due mainly to the edge scattering.

关键词： Graphene nanoribbons bipolar charge transport discontinuous Galerkin method

Helicobacter pylori gamma-glutamyl transpeptidase and its pathogenic role

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World Journal of Gastroenterology 2014年第3期20卷 630-638页

作者： vittorio Ricci Maria Giannouli Marco Romano Raffaele Zarrilli Department of Molecular Medicine Human Physiology SectionUniversity of Pavia Medical School Department of Public Health Hygiene SectionUniversity of Naples "Federico Ⅱ" Department of Clinical and Experimental Medicine Chair of GastroenterologySecond University of Naples CEINGE Biotecnologie Avanzate

Helicobacter pylori(***)gamma-glutamyl transpeptidase(GGT)is a bacterial virulence factor that converts glutamine into glutamate and ammonia,and converts glutathione into glutamate and *** GGT causes glutamine and glutathione consumption in the host cells,ammonia production and reactive oxygen species *** products induce cell-cycle arrest,apoptosis,and necrosis in gastric epithelial *** GGT may also inhibit apoptosis and induce gastric epithelial cell proliferation through the induction of cyclooxygenase-2,epidermal growth factor-related peptides,inducible nitric oxide synthase and *** GGT induces immune tolerance through the inhibition of T cell-mediated immunity and dendritic cell *** effect of GGT on *** colonization and gastric persistence are also discussed.

关键词： Helicobacter pylori Gamma-glutamyl transpeptidase Bacterial virulence factor Gastric epithelial cell damage T cell-mediated immunity

A Probabilistic Approach to the Evaluation of Seismic Resilience in Road Asset Management

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International Journal of Disaster Risk Science 2022年第1期13卷 114-124页

作者： vittorio Nicolosi Maria Augeri Mauro D'Apuzzo Azzurra Evangelisti Daniela Santilli Department of Enterprise Engineering“Mario Lucertini” University of Rome“Tor Vergata”00133 RomeItaly Department of Civil and Mechanical Engineering University of Cassino and Southern Lazio03043 CassinoItaly

Road networks are classified as critical infrastructure *** loss of functionality not only hinders residential and commercial activities,but also compromises evacuation and rescue after *** with risks to key strategic objectives is not new to asset management,and risk management is considered one of the core elements of asset *** analysis has recently focused on understanding and designing strategies for resilience,especially in the case of seismic events that present a significant hazard to highway transportation *** a review of risk and resilience concepts and metrics,an innovative methodology to stochastically assess the economic resources needed to restore damaged infrastructures,one that is a relevant and complementary element within a wider resilience-based framework,is *** original methodology is based on collecting and analyzing ex post reconstruction and hazard data and was calibrated on data measured during the earthquake that struck central Italy in 2016 and collected in the following recovery *** further improvements are needed,the proposed approach can be used effectively by road managers to provide useful information in developing seismic retrofitting plans.

关键词： Italy Resilience metrics Road asset management Road network resilience Seismic hazards

Unravelling the ion transport and the interphase properties of a mixed olivine cathode for Na-ion battery

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Journal of Energy Chemistry 2024年第9期96卷 300-317页

作者： Luca Minnetti Leonardo Sbrascini Antunes Staffolani vittorio Marangon Francesco Nobili Jusef Hassoun School of Sciences and Technologies–Chemistry Division University of CamerinoVia Madonna delle Carceri ChIP62032 CamerinoItaly Current affiliation:University of Bologna Department of Chemistry“Giacomo Ciamician”Via Francesco Selmi 240126 BolognaItaly Graphene Labs Istituto Italiano di Tecnologiavia Morego 30Genoa 16163Italy Department of Chemical Pharmaceutical and Agricultural SciencesUniversity of FerraraVia Fossato di Mortara 1744121 FerraraItaly GISEL−Centro di Riferimento Nazionale per i Sistemi di Accumulo Elettrochimico di Energia INSTMFirenze 50121Italy National Interuniversity Consortium of Materials Science and Technology(INSTM)University of Ferrara Research Unit University of FerraraVia Fossato di Mortara1744121 FerraraItaly

The replacement of Li by Na in an analogue battery to the commercial Li-ion one appears a sustainable strategy to overcome the several concerns triggered by the increased demand for the electrochemical energy ***,the apparently simple change of the alkali metal represents a challenging step which requires notable and dedicated ***,we investigate herein the features of a NaFe_(0.6)Mn_(0.4)PO_(4)(NFMP)cathode with triphylite structure achieved from the conversion of a LiFe_(0.6)Mn_(0.4)PO_(4)(LFMP)olivine for application in Na-ion *** work initially characterizes the structure,morphology and performances in sodium cell of NFMP,achieving a maximum capacity exceeding 100 mAh g^(−1)at a temperature of 55℃,adequate rate capability,and suitable retention confirmed by ex-situ ***,the study compares in parallel key parameters of the NFMP and LFMP such as Na^(+)/Li^(+)ions diffusion,interfacial characteristics,and reaction mechanism in Na/Li cells using various electrochemical *** data reveal that relatively limited modifications of NFMP chemistry,structure and morphology compared to LFMP greatly impact the reaction mechanism,kinetics and electrochemical *** changes are ascribed to the different physical and chemical features of the two compounds,the slower mobility of Na^(+)with respect to Li^(+),and a more resistive electrode/electrolyte interphase of sodium compared with ***,the study reveals analogue trends of the charge transfer resistance and the ion diffusion coefficient in NFMP and LFMP during the electrochemical process in ***,the NFMP achieved herein is suggested as a possible candidate for application in a low-cost,efficient,and environmentally friendly Na-ion battery.

关键词： NaFe_(0.6)Mn_(0.4)PO_(4)NFMP Olivine Na-ion lon transport Interphase

Vascular injury during laparoscopic cholecystectomy:An oftenoverlooked complication

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World Journal of Gastrointestinal Surgery 2023年第3期15卷 338-345页

作者： Antonio Pesce Nicolò Fabbri Carlo vittorio Feo Department of Surgery University of FerraraAzienda USL of FerraraAzienda USL of FerraraLagosanto 44023FerraraItaly

Laparoscopic cholecystectomy is one of the most frequently performed procedures in gastrointestinal surgery *** complications due to vascular injuries represent an important cause of morbidity and mortality,especially when facing major bleeding during laparoscopy,where bleeding control can be technically challenging in inexperienced ***,the reported incidence rate of conversion to open surgery due to vascular lesions is approximately 0%-1.9%,with a mortality rate of approximately 0.02%.The primary aim of this article was to perform an up-to-date overview regarding the incidence and surgical management of vascular injuries during laparoscopic cholecystectomy according to the available scientific evidence.

关键词： Laparoscopic cholecystectomy Vascular injury Vascular anomalies Surgical management Specialized hepatobiliary centers

Parallel pathways:A chronicle of evolution in rectal and breast cancer surgery

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1091-1096页

作者： Antonio Pesce NicolòFabbri Diletta Iovino Carlo vittorio Feo Unit of General Surgery University of FerraraAzienda USL of FerraraFerrara 44023LagosantoItaly

In this editorial,we have analyzed the historical evolution of rectal and breast cancer surgery,focusing on the progressive reduction of demolitive approaches and the increasing use of more conservative strategies,accompanied by a growing emphasis on perioperative treatments aimed at enhancing surgical *** of these changes have been made possible due to an increased awareness and understanding of oncological diseases and improved perioperative treatments.

关键词： Rectal cancer History Breast surgery Demolitive treatment Conservative surgery

Large-area patterning of substrate-conformal MoS2 nano-trenches

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Nano Research 2019年第8期12卷 1851-1854页

作者： Christian Martella Luca Ortolani Elena Cianci Alessio Lamperti vittorio Morandi Alessandro Molle IMM-CNR via C. Olivetti 2Agrate Brianza (MB) 1-20864Italy ISC-CNR U.O.S. SapienzaRoma 1-00185Italy IMM-CNR via Gobetti 101Bologna (BO) 1-40129Italy

Within the class of two-dimensional materials, transition metal dichalcogenides (TMDs), are extremely appealing for a variety of technological applications. Moreover, the manipulation of the layered morphology at the nanoscale is a knob for further tailoring their physical and chemical properties towards target applications. Here, the combination of atomic layer deposition (ALD) and chemical vapour deposition (CVD) is presented as a general approach for the fabrication of TMD layers arranged in arbitrary geometry at the nanoscale. Indeed, following such all-chemical based approach, high-resolution electron microscopy shows the conformal growth of MoS2 to nano-trench pattern obtained in SiO2 substrates on large area. Growth is uniform not only in the flat region of the pattern but also at the hinges and throughout vertical faces, without rupture, all along the rectangular shape profile of the trenches. Furthermore, MoS2 bending dramatically affects the electron-phonon coupling as demonstrated by resonant Raman scattering. The proposed approach opens the door to the on-demand manipulation of the TMDs properties by large-scale substrate pattern design.

关键词： two-dimensional (2D) materials transition metal dichalcogenides nano-trenches conformal growths high-resolution electron microscopy