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Long COVID in children and adolescents

World Journal of Pediatrics 2021年第5期17卷 495-499页

作者： Ali A.Asadi-Pooya Hamid Nemati Mina Shahisavandi Ali Akbari Amir Emami mehrzad lotfi Mahtab Rostamihosseinkhani Zohreh Barzegar Maryam Kabiri Zahra Zeraatpisheh Mohsen Farjoud-Kouhanjani Anahita Jafari Fateme Sasannia Shayan Ashrafi Masoume Nazeri Sara Nasiri Epilepsy Research Center Shiraz University of Medical SciencesShirazIran Department of Ncurology Jefferson Comprehensive Epilepsy CenterThomas Jefferson UniversityPhiladelphiaPAUSA Department of Anesthesiology School of Medicine.Shiraz University of Medical SciencesShirazIran Burn&Wound Healing Research Center Shiraz University of Medical SciencesShirazIran Medical Imaging Research Center Shiraz University of Medical SciencesShirazIran

Background To identify the prevalence and also the full spectrum of symptoms/complaints of children and adolescents who are suffering from long ***,we investigated the risk factors of long COVID in children and *** All consecutive children and adolescents who were referred to the hospitals anywhere in Fars province,Iran,from 19 February 2020 until 20 November 2020 were *** patients had a confirmed diagnosis of *** *** call to patients/parents,at least 3 months after their discharge from the hospital,we obtained their current status and information if their parents agreed to *** In total,58 children and adolescents fulillel the inclusion ***-six(448%)children/adolescents reported symptoms/complaints of long *** symptoms included fatigue in 12(21%),shortness of breath in 7(12%),exer-cise intolerance in 7(12%),weakness in 6(10%),and walking intolerance in 5(9%)*** age,muscle pain on admission,and intensive care unit admission were significantly associated with long *** Long COVID is a frequent condition in children and *** scientific community should inves-tigate and explore the pathophysiology of long COVID to ensure that these patients receive appropriate treatments for their condition.

关键词： Adolescents Children COVID-19 Coronavirus Chronic Pediatrics

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Elevated temperature oxidation behavior of HVOF sprayed TiB_2 cermet coating

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Transactions of Nonferrous Metals Society of China 2010年第2期20卷 243-247页

作者： Behnam lotfi Department of Materials Engineering Faculty of EngineeringShahid Chamran UniversityAhvazIran

Oxidation behaviors of Ni(Cr)-TiB2 coating deposited by HVOF technique were studied at 800,900 and 1 000℃in air. The microstructures of as-sprayed and oxidized coatings were characterized by X-ray diffractometry(XRD)and scanning electron microscopy(SEM).After oxidation at 800℃,a thin and adherent oxide layer was formed on the surface of the *** increasing exposure temperature,the thickness of the oxide layer increased;and at 1 000℃the oxide layer separated from the *** of the kinetics of oxidation by using the thermogravimetric analysis(TGA)technique shows a parabolic oxidation rate.

关键词： TiB2 cermet coating thermal spraying oxidation

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Design issues for human-machine platform interface in cable-based parallel manipulators for physiotherapy applications

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第4期11卷 231-239页

作者： Marco CECCARELLI lotfi ROMDHANE Laboratory of Robotics and Mechatronics DIMSATUniversity of Cassino-CassinoItaly Département de Mécanique Avancée Ecole Nationale d'Ingénieurs de SousseTunisia

We outline problems and potential solutions for feasible human-machine interfaces using cable-based parallel manipulators for physiotherapy *** an engineering perspective,we discuss the design constraints related to acceptance by patients and physiotherapist *** date,most designs have focused on mobile platforms that are designed to be operated as an end-effector connected to human limbs for direct patient *** specific examples are illustrated from the authors' experience with prototypes available at Laboratory of Robotics and Mechatronics (LARM),Italy.

关键词： Robot design Robot applications Cable-based parallel manipulators Human-machine mechanical interfaces

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An Efficient Two-Phase Model for Computing Influential Nodes in Social Networks Using Social Actions

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Journal of Computer Science & Technology 2018年第2期33卷 286-304页

作者： Mehdi Azaouzi lotfi Ben Romdhane Modeling of Automated Reasoning Systems Research Laboratory LR17ES05 Higher Institute of Computer Science and Telecom University of Sousse Sousse 526-~002 Tunisia

The measurement of influence in social networks has received a lot of attention in the data mining community. Influence maximization refers to the process of finding influential users who make the most of information or product adoption. In real settings, the influence of a user in a social network can be modeled by the set of actions （e.g., ＂like＂, ＂share＂, ＂retweet＂, ＂comment＂） performed by other users of the network on his/her publications. To the best of our knowledge, all proposed models in the literature treat these actions equally. However, it is obvious that a ＂like＂ of a publication means less influence than a ＂share＂ of the same publication. This suggests that each action has its own level of influence （or importance）. In this paper, we propose a model （called Social Action-Based Influence Maximization Model, SAIM） for influence maximization in social networks. In SAIM, actions are not considered equally in measuring the ＂influence power＂ of an individual, and it is composed of two major steps. In the first step, we compute the influence power of each individual in the social network. This influence power is computed from user actions using PageRank. At the end of this step, we get a weighted social network in which each node is labeled by its influence power. In the second step of SAIM, we compute an optimal set of influential nodes using a new concept named ＂influence-BFS tree＂. Experiments conducted on large-scale real-world and synthetic social networks reveal the good performance of our model SAIM in computing, in acceptable time scales, a minimal set of influential nodes allowing the maximum spreading of information.

关键词： social network social influence social action personalized PageRank influence-BFS tree

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Microstructure and Sliding Wear Behaviour of Ni(Cr)-TiB_2 Coatings Deposited by HVOF Spraying of SHS Powders

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材料热处理学报 2004年第5B期25卷 1183-1186页

作者： Behnam lotfi Zohreh Sadeghian Faculty of Engineering Department of Materials Engineering Shahrecord University Shahrecord IranDepartment of Materials Science and Engineering Isfahan University of Technology Isfahan Iran

This work reports research concerning the microstructure and sliding wear behaviour of cermet coatings deposited by high velocity oxy-fuel (HVOF) spraying. Two cermets were prepared with the following target compositions namely, Ni (Cr)-65 wt.% TiB2 and Ni (Cr)-40 wt.% TiB2. Coating microstructures were investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD), whilst microhardness and sliding wear tests were performed on the coatings to evaluate their performance. The HVOF sprayed deposits had layered, splat-like morphologies typical of thermally sprayed cermets. Coatings consisted primarily of TiB2 particles in a nickel-based binder phase. Other minor peaks in the XRD patterns belong to TiB, Ni2B, NiTiO3 and Ti2Oj. The coatings exhibit an amorphous halo in the diffraction pattern between 2 values of 40° and 50°. Sliding wear behaviour was examined using a conventional ball-on-disc apparatus. A sintered ceramic ball (A12O3) was employed as the counterface. The Ni (Cr)-65 wt.% TiB2 coating had a lower wear rate than Ni (Cr)-40 wt.% TiB2 coating. This may be related to the larger sizes of borides. Wear scar morphologies, on both coatings were examined by using SEM and EDAX detecting in order to establish the wear mechanism. Wear is proposed to proceed by subsurface cracking in these coatings.

关键词：显微结构滑动磨损 SHS HVOF Ni(Cr)-TiB2合金

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High performance novel flexible perovskite solar cell based on a low-cost-processed ZnO:Co electron transport layer

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Nano Research 2020年第9期13卷 2546-2555页

作者： Feriel Bouhjar lotfi Derbali BernabéMari Institut de Disseny i Fabricació(IDF)-Departament de Fisica Aplicada Universitat Politecnica de Valenciciy Cami de Vera s/n46022 ValenciaSpain Photovoltaic Laboratory Research and Technology Centre of Energy(CRTEn)Borj-Cedria Science and Technology Parky BP 952050 Hammam-LifTunisia Laboratory of Semiconductors Nanostructures and Advanced TechnologyResearch and Technology Center of Energy(CRTEn)Borj-Cedria Science and Technology ParkBP 952050 Hammam-LifTunisia Department of Physics College of Sciences and HumanitiesAl QuwayiyahShaqraa UniversityAl QuwayiyahSaudi Arabia

In this work,high quality uniform and dense nanostructured cobalt-doped zinc oxide(ZnO:Co)films were used as electron-transport layers in CH3NH3Pbl3-based planar heterojunction perovskite solar cells(PSCs)on a flexible conductive *** photo catalytically active ZnO:Co films were prepared by a low cost hydrothermal process using the aqueous solution of zinc nitrate hexahydrate,hexamethylenete-tramine and cobalt(II)nitrate ***:Co films were deposited on indium tin oxide(ITO)covered polyethylene terephthalate(PET)flexible *** growth was controlled by maintaining the autoclave temperature at 150℃for 4 *** CH3NH3Pbl3 layer was deposited on the ZnO:Co films by spin ***-OMeTAD was employed as a hole-transporting *** structural,morphology and optical properties of the grown ZnO nanostructures were characterized by X-ray diffraction(XRD),field-emission scanning electron microcopy(FESEM),energy-dispersive X-ray spectrometry(EDX),ultraviolet-visible(UV-Vis)and photoelectrochemical *** spectra showed that both ZnO and ZnO:Co nanorods had a hexagonal wurtzite structure with a strong preferred orientation along the(002)*** surface morphology of films was studied by FESEM and showed that both the pure and Co-doped ZnO films had hexagonal shaped *** the steady state,the ZnO electrode gave a photocurrent density of about 1.5 mA/***,the Co-doped ZnO electrode showed a photocurrent density of about 6 mA/cm^2,which is 4-fold higher than that of the ZnO *** on the above synthesized Co-doped ZnO films,the photovoltaic performance of PSCs was *** Co-doped ZnO layers had a significant impact on the photovoltaic conversion efficiency(PCE)of the *** latter was attributed to an efficient charge separation and transport due to the better coverage of perovskite on the nanostructured Co-doped ZnO *** a result,the measured PCE under standard solar conditions(A M 1.5G,100 mW/cm^2)r

关键词： perovskite solar cell ZnO nanorods hydrotherm al deposition X-ray diffraction(XRD)analysis field-em ission scanning electron m icrocopy(FESEM)analysis photoelectrochem ical properties

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Hybrid Flow Shop with Setup Times Scheduling Problem

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Computer Systems Science & Engineering 2023年第1期44卷 563-577页

作者： Mahdi Jemmali lotfi Hidri Department of Computer Science and Information College of Science at ZulfiMajmaah UniversityMajmaah11952Saudi Arabia Mars Laboratory University of SousseSousseTunisia Department of Computer Science Higher Institute of Computer Science and Mathematics of MonastirMonastir UniversityMonastir5000Tunisia Industrial Engineering Department College of EngineeringKing Saud UniversityRiyadh11421Saudi Arabia

The two-stage hybridflow shop problem under setup times is addressed in this *** problem is *** the other hand,the studied problem is modeling different real-life applications especially in manufacturing and high *** this kind of problem requires the development of adapted *** this context,a metaheuristic using the genetic algorithm and three heuristics are proposed in this *** approximate solutions are using the optimal solution of the parallel machines under release and delivery ***,these solutions are iterative procedures focusing each time on a particular stage where a parallel machines problem is called to be *** general solution is then a concatenation of all the solutions in each *** addition,three lower bounds based on the relaxation method are *** lower bounds present a means to evaluate the efficiency of the developed algorithms throughout the measurement of the relative *** experimental result is discussed to evaluate the performance of the developed *** total,8960 instances are implemented and tested to show the results given by the proposed lower bounds and *** indicators are given to compare between *** results illustrated in this paper show the performance of the developed algorithms in terms of gap and running time.

关键词： Hybridﬂow shop genetic algorithm setup times heuristics lower bound

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Hydrogen Detection With FBG Sensor Technology for Disaster Prevention

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Photonic Sensors 2013年第3期3卷 214-223页

作者： Said SAAD lotfi HASSINE Group of Electronics and Quantum Physics Laboratory of Advanced Materials and Quantum Phenomena Faculty of Sciences of Tunis 2092 Tunisia National Institute of Applied Sciences and Technology University of Carthage North Urban Center of Tunis-B.P.676 Cedex Tunis-1080 Tunisia

Three fiber Bragg grating （FBG） sensors systems for hydrogen detection are presented using the classic Pd （palladium） coating technique （500nm） as the hydrogen sensitive film and titanium （Ti） as the adhesive layer with the etched cladding. These systems are compared and used for disaster environment prevention in hydrogen leakage environment where higher values than the normal are presented which increase the risk of explosion. With these systems, 0. 1% - 4% of the hydrogen volume concentration range in the volume ratio was detected and monitored experimentally in the test room with the very sensitive and stable value which reached 60pm/1% HE. In addition, a fast response time, about 6 s, was obtained with an advanced sensor.

关键词： Fiber Bragg gratin (FBG) hydrogen detection sensor disaster environment prevention Pd coating technique

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Impurity effects on electrical conductivity of doped bilayer graphene in the presence of a bias voltage

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Chinese Physics B 2016年第7期25卷 316-323页

作者： E lotfi H Rezania B Arghavaninia M Yarmohammadi Department of Physics Sanandaj Branch Islamic Azad University Department of Physics Razi University Department of Physics Kermanshah Branch Islamic Azad University Young researchers and Elite Club Kermanshah Branch Islamic Azad University

We address the electrical conductivity of bilayer graphene as a function of temperature, impurity concentration, and scattering strength in the presence of a finite bias voltage at finite doping, beginning with a description of the tight-binding model using the linear response theory and Green＇s function approach. Our results show a linear behavior at high doping for the case of high bias voltage. The effects of electron doping on the electrical conductivity have been studied via changing the electronic chemical potential. We also discuss and analyze how the bias voltage affects the temperature behavior of the electrical conductivity. Finally, we study the behavior of the electrical conductivity as a function of the impurity concentration and scattering strength for different bias voltages and chemical potentials respectively. The electrical conductivity is found to be monotonically decreasing with impurity scattering strength due to the increased scattering among electrons at higher impurity scattering strength.

关键词： bilayer graphene Green's function electrical conductivity

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Analysis and optimal synthesis of single loop spatial mechanisms

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第9期12卷 665-679页

作者： Med Amine LARIBI lotfi ROMDHANE Sad ZEGHLOUL Laboratoire de Génie Mécanique LAB-MA-05 Ecole Nationale d'Ingénieurs de Sousse Institut Pprime-UPR 3346 CNRS-Université de Poitiers-ENSMA Département Génie Mécanique et Systémes Complexes SP2MIBP30179 86962 Futuroscope France

In this work, a systematic approach is presented to obtain the input-output equations of a single loop 4-bar spatial mechanisms. The dialytic method along with Denavit-Hartenberg parameters can be used to obtain these equations efficiently. A genetic algorithm （GA） has been used to solve the problem of spatial mechanisms synthesis. Two types of mechanisms, e.g., RSCR and RSPC （R： revolute; S： spherical; C： cylindrical; P： prismatic）, have illustrated the application of the GA to solve the problem of function generation and path generation. In some cases, the GA method becomes trapped in a local minimum. A combined GA-fuzzy logic （GA-FL） method is then used to improve the final result. The results show that GAs, combined with an adequate description of the mechanism, are well suited for spatial mechanism synthesis problems and have neither difficulties inherent to the choice of the initial feasible guess, nor a problem of convergence, as it is the case for deterministic methods.

关键词： Spatial mechanisms Genetic algorithm-fuzzy logic (GA-FL) method Denevit-Hartenberg parameters Mechanism synthesis

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