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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

study of corneal biomechanical properties in patients with childhood glaucoma

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International Journal of Ophthalmology(English edition) 2020年第12期13卷 1922-1927页

作者： sara Garcia Caride Lucia Perucho González Federico sáenz Francés Julián García Feijoo Ophthalmology Clinico San Carlos HospitalProfesor Martín Lagos StreetMadridES 28040Spain

AIM:To study of corneal biomechanical properties and intraocular pressure(IOP)measured with Corvis scheimpflug Technology(sT)in patients with childhood glaucoma(CG).METHODs:Cross-sectional study in which 89 eyes were included 56 of them with *** one eye per patient was *** following variables were obtained from the clinical history and the ophthalmological examination:age,sex,IOP,number of surgeries,and the cup/disc ratio(CDR).The following parameters were recorded using Corvis sT:corrected by biomechanics IOP(b IOP),not corrected IOP(nct IOP),central corneal thickness(CCT),maximum concavity[radius,peak distance(PD)and deformation amplitude],applanation 1 and 2(length and velocity).The mean age was 23±14.55 and 33±19.5 years old for the control group and CG group,*** 36 were males and 53 were *** the CG group,7 patients were controlled only with medical *** had at least one previous goniotomy,19 had at least one trabeculectomy,and 11 had an Ahmed ***:A significant and positive intraclass correlation coefficient was found between Goldman IOP and the IOP measured by Corvis in both *** differences were found between the IOP measured with Corvis and Goldman using a student *** biomechanical parameters,there were differences in the applanation length 2(A-L2),in the applanation velocity 2(A-V2)and in the *** sex,only the applanation length 1(A-L1)was found to be different in control group.A positive and significant Pearson correlation was found between CDR and the ***:Corneal biomechanical properties have shown differences between CG and healthy subjects and also between men and women.

关键词： childhood glaucoma biomechanical properties Corvis scheimpflug Technology

secondary Hyperparathyroidism in Dialysis Patients: short- and Long-Term Outcomes of Conservative Parathyroidectomy

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Orchestrating stem cell fate: Novel tools for regenerative medicine

Open Journal of Nephrology（肾脏病） 2024年第2期 147页

作者： Imane saidi sara Elmaakoul Naima Ouzeddoun Loubna Benamar

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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

Role of adipose tissue grafting and adipose-derived stem cells in peripheral nerve surgery

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Neural Regeneration Research 2022年第10期17卷 2179-2184页

作者： Tiam M.saffari sara.saffari Krishna s.Vyas samir Mardini Alexander Y.shin Department of Orthopedic surgery Division of Microvascular and Hand SurgeryMayo ClinicRochesterMNUSA Radboud University Medical Center Radboud Institute for Health SciencesDepartment of Plastic SurgeryNijmegenThe Netherlands Department of surgery Division of Plastic and Reconstructive SurgeryMayo ClinicRochesterMNUSA

The application of autologous fat grafting in reconstructive surgery is commonly used to improve functional *** review aims to provide an overview of the scientific evidence on the biology of adipose tissue,the role of adipose-derived stem cells,and the indications of adipose tissue grafting in peripheral nerve *** tissue is easily accessible through the lower abdomen and inner ***-vascularized adipose tissue grafting does not support oxidative and ischemic stress,resulting in variable survival of adipocytes within the first 24 *** of adipose tissue with a stromal vascular fraction is purported to increase the number of adipose-derived stem cells and is postulated to augment the long-term stability of adipose tissue *** science nerve research suggests an increase in nerve regeneration and nerve revascularization,and a decrease in nerve fibrosis after the addition of adipose-derived stem cells or adipose *** clinical studies,the use of autologous lipofilling is mostly applied to secondary carpal tunnel release revisions with promising *** the use of adipose-derived stem cells in peripheral nerve reconstruction is relatively new,more studies are needed to explore safety and long-term effects on peripheral nerve *** Food and Drug Administration stipulates that adipose-derived stem cell transplantation should be minimally manipulated,enzyme-free,and used in the same surgical procedure,*** tissue grafts that contain native adipose-derived stem cells or stromal vascular *** research may be shifted towards the use of tissue-engineered adipose tissue to create a supportive microenvironment for autologous graft ***-ready alternatives could be enhanced with adipose-derived stem cells or growth factors and eliminate the need for adipose tissue harvest.

关键词： adipose tissue adipose-derived stem cells angiogenesis autologous fat grafting nerve injury nerve regeneration paracrine environment peripheral nerve reconstruction stem cell secretome tissue engineering

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

Comparative analysis of ERCP,IDUs,EUs and CT in predicting malignant bile duct strictures

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World Journal of Gastroenterology 2014年第30期20卷 10495-10503页

作者： Hauke s Heinzow sara Kammerer Carina Rammes Johannes Wessling Dirk Domagk Tobias Meister Department of Medicine B University of MünsterD-48149 MünsterGermany Department of Clinical Radiology University of MünsterD-48149 MünsterGermany Department of Radiology ClemenshospitalMünster University Teaching HospitalD-48153 MünsterGermany Department of Medicine Ⅱ HELIOS AlbertSchweitzer HospitalG?ttingen University Teaching HospitalD-37154 NortheimGermany

AIM: To compare endoscopic retrograde cholangio-pancreatography (ERCP), intraductal ultrasound (IDUs), endosonography (EUs), endoscopic transpapillary forceps biopsies (ETP) and computed tomography (CT) with respect t... 详细信息

关键词： Intraductal ultrasound Intraductal ultrasound Bile duct strictures Endosonography Computed tomography Malignancy