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Dynamical Study of a Constant Viscous Dark Energy Model in Classical and Loop Quantum Cosmology

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Chinese Physics Letters 2016年第5期33卷 144-148页

作者： sara Benchikh Noureddine Mebarki Dalel Aberkane Laboratoire de Physique Mathematique et Subatomique Mentouri University

Dynamical behaviors and stability properties of a flat space Friedmann-Robertson-Walker universe filled with pressureless dark matter and viscous dark energy are studied in the context of standard classical and loop quantum cosmology. Assuming that the dark energy has a constant bulk viscosity, it is found that the bulk viscosity effects influence only the quintessence model case leading to the existence of a viscous late time attractor solution of de- Sitter type, whereas the quantum geometry effects influence the phantom model case where the big rip singularity is removed. Moreover, our results of the Hubble parameter as a function of the redshift are in good agreement with the more recent data.

关键词： of on in Dynamical Study of a Constant Viscous Dark Energy Model in Classical and Loop Quantum Cosmology is that for been FRW

Orchestrating stem cell fate: Novel tools for regenerative medicine

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World Journal of Stem Cells 2019年第8期11卷 464-475页

作者： sara Cruciani sara Santaniello Andrea Montella Carlo Ventura Margherita Maioli Department of Biomedical Sciences University of Sassari Sassari 07100 Italy Laboratory of Molecular Biology and Stem Cell Engineering National Institute of Biostructures and Biosystems – Eldor Lab Innovation Accelerator Consiglio Nazionale delle Ricerche Bologna 40129 Italy Operative Unit of Clinical Genetics and Developmental Biology Sassari 07100 Italy Istituto di Ricerca Genetica e Biomedica Consiglio Nazionale delle Ricerche Cagliari 09042 Italy Center for Developmental Biology and Reprogramming-CEDEBIOR Department of Biomedical Sciences University of Sassari Sassari 07100 Italy

Mesenchymal stem cells are undifferentiated cells able to acquire different phenotypes under specific stimuli. In vitro manipulation of these cells is focused on understanding stem cell behavior, proliferation and pluripotency. Latest advances in the field of stem cells concern epigenetics and its role in maintaining self-renewal and differentiation capabilities. Chemical and physical stimuli can modulate cell commitment, acting on gene expression of Oct-4, Sox-2 and Nanog, the main stemness markers, and tissue-lineage specific genes. This activation or repression is related to the activity of chromatin-remodeling factors and epigenetic regulators, new targets of many cell therapies. The aim of this review is to afford a view of the current state of in vitro and in vivo stem cell applications, highlighting the strategies used to influence stem cell commitment for current and future cell therapies. Identifying the molecular mechanisms controlling stem cell fate could open up novel strategies for tissue repairing processes and other clinical applications.

关键词： Stem cells Epigenetics Self-renewal In vitro differentiation Physical stimuli Stem cell fate Clinical practice Cell transplantation

Fuzzy-entropy based robust optimization criteria for tuned mass dampers

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 285-294页

作者： Giuseppe Carlo Marano Giuseppe Quaranta sara Sgobba Department of Environmental Engineering and Sustainable Development Technical University of Bari Department of Structural Engineering and Geotechnics University of Rome "La Sapienza" Faculty of Engineering International University UNINETTUNO

Tuned mass dampers (TMD) are well known as one of the most widely adopted devices in vibration control passive strategies. In the past few decades,many methods have been developed to find the optimal parameters of a TMD installed on a structure and subjected to a random base excitation process,but most of them are usually based on an implicit assumption that all of the structural parameters are deterministic. However,in many real cases this simplification is unacceptable,so robust optimal design criteria becomes aviable alternative to better support engineers in the design process. In Robust Design Optimization (RDO) approaches,indeed the solution must be able to not only minimize the performance but also to limitits variation induced by uncertainty. Most of the currently available RDO methods are based on a probabilistic description of the model uncertainty,even if in many cases they are not able to explicitly include the influence of all the possible sources of uncertainties. Therefore,in this study,a fuzzy version of the robust TMD design optimization problem is proposed. The consistency of the fuzzy approach is studied with respect to the available non-probabilistic formulations reported in the literature and an application to an example of a robust design of a linear TMD subjected to base random vibrations in the presence of fuzzy uncertainties. The results show that the proposed fuzzy-based approach is able to give a set of optimal solutions both in terms of structural efficiency and sensitivity to mechanical and environmental uncertainties.

关键词： tuned mass damper random vibration robust design fuzzy variable expected value fuzzy entropy

XRD study of intercalation in statically annealed composites of ethylene copolymers and organically modified ***-tailed organoclays

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International Journal of Smart and Nano Materials 2014年第1期5卷 59-74页

作者： sara Filippi Giovanni Polacco Department of Civil and Industrial Engineering University of PisaLargo Lucio Lazzarino156126 PisaItaly

Ethylene copolymers with different polar comonomers,such as vinyl acetate,methyl acrylate,glycidyl methacrylate,and maleic anhydride,were used for the preparation of polymer/clay nanocomposites by statically annealing their mechanical mixtures with different commercial or home-made organically modified montmorillonites containing only one long alkyl *** nanostructure of the products was monitored by X-ray diffraction,and the dispersion of the silicate particles within the polymer matrix was qualitatively evaluated through microscopic *** effect of the preparation conditions on the structure and the morphology of the composites was also addressed through the characterization of selected samples with similar composition prepared by melt *** agreement with the findings reported in a previous paper for the composites filled with two-tailed organoclays,intercalation of the copolymer chains within the tighter galleries of the one-tailed clays occurs easily,independent of the application of a mechanical ***,the shear-driven break-up of the intercalated clay particles into smaller platelets(exfoliation)seems more hindered.A collapse of the organoclay interlayer spacing was only observed clearly for a commercial one-tailed organoclay-Cloisite®30B–whereas the same effect was almost negligible for a home-made organoclay with similar structure.

关键词： ethylene copolymers one-tailed organoclays annealing X-ray diffraction

ON MODELING THE GROWTH DYNAMICS OF A STAGE STRUCTURED POPULATION

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International Journal of Biomathematics 2013年第6期6卷 29-52页

作者： GIUSEPPE BUFFONI sara PASQUALI CNR-IMATI Via Bassini 15 20133 Milano Italy

A Lagrangian modeling approach is applied to the numerical simulation of the temporal dynamics of a stage-structured population. The growth dynamics is determined only by the main biological processes： development of an individual, mortality, reproduction. Different approaches in modeling the development process of an individual are implemented： stochastic advection-diffusion models （backward-forward dispersion models）, and stochastic development models where regression effects, defined as negative development on the status of an individual, are forbidden （forward dispersion models）. Some properties of the residence times of an individual in a stage are investigated： in particular, their role in the calibration of the development models and in the estimation of some parameters introduced in the model equation. As a study case a multi-stage pelagic copepod population is considered. Trying to separate the effects of the main biological processes on the temporal dynamics, numerical simulations have been carried out in some idealized situations： first only the development of the individuals, neglecting mortality and reproduction, is considered; then the mortality process is introduced, and finally both the mortality and reproduction processes. The results of the numerical simulations, are compared and discussed.

关键词： Stage structure residence time in a stage stochastic development models

Machine Learning Techniques for Software Maintainability Prediction:Accuracy Analysis

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Journal of Computer Science & Technology 2020年第5期35卷 1147-1174页

作者： sara Elmidaoui Laila Cheikhi Ali Idri Alain Abran Softtrare Project Management TeamEcole Nationale Superieure d'Informattique et d'Analyse des SystemesMadinate Al IrfaneMohammed V University in Rabat.Agdal RabatBP 713Morocco Department of Software Engineering&Infonnation Technology Ecole de Technologie Superieure(ETS)Montreal HSC IKSCanada

Maintaining software once implemented on the end-user side is laborious and,over its lifetime,is most often considerably more expensive than the initial software *** prediction of software maintainability lias emerged as an important research topic to address industry expectations for reducing costs,in particular,maintenance *** and practitioners have been working on proposing and identifying a variety of techniques ranging from statistical to machine learning(ML)for better prediction of software *** review has been carried out to analyze the empirical evidence on the accuracy of software product maintainability prediction(SPMP)using ML *** paper analyzes and discusses the findings of 77 selected studies published from 2000 to 2018 according to the following criteria:maintainability prediction techniques,validation methods,accuracy criteria,overall accuracy of ML techniques,and the techniques offering the best *** review process followed the well-known syslematic review *** results show that ML techniques are frequently used in predicting *** particular,artificial neural network(ANN),support vector machine/regression(SVM/R).regression&decision trees(DT),and fuzzy neuro fuzzy(FNF)techniques are more accurate in terms of PRED and *** N-fold and leave-one-out cross-validation methods,and the MMRE and PRED accuracy criteria are frequently used in empirical *** general,ML techniques outperformed non-machine learning techniques,e.g.,regression analysis(RA)techniques,while FNF outperformed SVM/*** ANN in most ***,while many techniques were reported superior,no specific one can be identified as the best.

关键词： accuracy criterion accuracy value machine learning technique maintainability prediction

Photocatalytic activity of cation(Mn) and anion(N) substitution in LaCoO3 nanoperovskite under visible light

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Rare Metals 2020年第2期39卷 139-146页

作者： Parvaneh Nakhostin Panahi Mohammad Hossein Rasoulifard sara Babaei Department of Chemistry Faculty of ScienceUniversity of ZanjanZanjan ***Iran

LaCoO3 compound and novel photocatalysts of LaCo0.8Mn0.2O3 and N-doped LaCoO3 were synthesized by sol-gel *** structure,morphology,size of particles and optical properties of the obtained powders were characterized by X-ray diffractometer(XRD),scanning electron microscopy(SEM) and ultraviolet-visible(UV-Vis)(DRS mode) *** perovskite structure obtained for all the prepared samples and doping Mn and N do not change the perovskite *** results revealed that the size of particles of all perovskites was less than 100 *** to that of parent LaCoO3,the band gap energy of LaCo0.8Mn0.2O3 and N-doped LaCoO3 considerably reduced due to the formation of impurity *** photocatalytic activity of all samples was evaluated by the degradation of malachite green as a model dye under visible light *** discoloration induced by LaCo0.8Mn0.2O3 was twice that induced by pure LaCoO3 because of Mn ions with variable valance and smaller band gap *** nitrogen incorporation also significantly improved the photocatalytic activity of LaCoO3 due to more oxygen vacancies and the stronger absorption in visible *** general,doping has been served as one of the most efficient methods for the improvement in band gap of photocatalysts.

关键词： Nanoperovskite Photocatalyst Dyes contaminant Mn doping N doping

A comparison of condensate mass of QCD vacuum between Wilson line approach and Schwinger effect

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Chinese Physics C 2021年第4期45卷 123-129页

作者： sara Tahery Xurong Chen Liping Zou Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beiing 100049China Guangdong Provincial Key Laboratory of Nuclear Science Institute of Quantum MatterSouth China Normal UniversityGuangzhou 510006China

We studied the condensate mass of QCD vacuum through the duality approach via dilaton wall back-ground in the presence of the parameter c,which represents the condensation in a holographic set ***,fromWilson line calculation,we found m_(0)^(2)(i.e.,the condensate parameter in mixed non-local condensation),whose beha-vior mimics that of *** value of m_(0)^(2)that we found by this approach is in agreement with QCD *** we considered the produced mass m via the Schwinger effect mechanism in the presence of the parameter *** show that vacuum condensation generally contributes the mass dominantly and that the produced mass via *** effect is suppressed by m_(0).

关键词： AdS/QCD holographic Schwinger effect gluon condensation of vacuum

Optimization of the treatment with immunosuppressants and biologics in inflammatory bowel disease

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World Journal of Gastroenterology 2014年第29期20卷 9675-9690页

作者： sara Renna Ambrogio Orlando Division of Internal Medicine ‘‘Villa Sofia-V.Cervello’’ Hospital

Many placebo controlled trials and meta-analyses evaluated the efficacy of different drugs for the treatment of inflammatory bowel disease (IBD), including immunosuppressants and biologics. Their use is indicated in moderate to severe disease in non responders to corticosteroids and in steroid-dependent patients, as induction and maintainance treatment. Infliximab, as well as cyclosporine, is considered a second line therapy in the case of severe ulcerative colitis, or non-responders to intravenous corticosteroids. An adequate dosage and duration of therapy with thiopurines should be reached before evaluating their efficacy. Methotrexate is a valid option in patients with Crohn’s disease but its use is confined to patients who are intolerant or non-responders to thiopurines. Evidence for the use of methotrexate in ulcerative colitis is insufficient. The use of thalidomide and mycophenolate mofetil is not recommended in patients with inflammatory bowel disease, these treatments could be considered in case of failure of all other therapeutic options. In patients with moderately active ulcerative colitis, refractory to thiopurines, the use of tacrolimus is considered an alternative to biologics. An increase of the dose or a decrease in the interval of administration of biological treatment could be useful in the presence of an incomplete clinical response. In the case of primary failure of an anti-tumor necrosis factor alpha a switch to another one should be considered. Data on the efficacy of combination therapy are up to now insufficient to consider this strategy in all IBD patients. The final outcome of the treatment should be considered the clinical remission, with mucosa healing, and not the clinical response. The evaluation of serum concentration of thiopurine methyl transferase activity, thiopurine metabolites, biologic serum levels and antibiologic antibodies could be useful for the management of the treatment but it has not been routinely applied in cl

关键词： Inflammatory bowel disease Optimization Immosuppressants Biologics Crohn's disease Ulcerative colitis