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Aging effect and test-retest reliability of the sinusoidal harmonic acceleration test and velocity step test using nanotorque rotatory chair

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Journal of Otology 2023年第3期18卷 125-131页

作者： Nourhan Ghoraba samir Assal Doaa Elmoazen Audiovestibular Medicine Unit Otorhinolaryngology DepartmentFaculty of MedicineAlexandria UniversityEgypt

Introduction:Rotatory chair testing has been used to evaluate horizontal canal *** used tests include sinusoidal harmonic acceleration test(SHAT)and velocity step test(VST).Objectives:Assessment of age effect on the SHAT and VST and assessment of test-retest reliability of the parameters of those two ***:A prospective study was performed on 100 subjects with no ear or vestibular complaints and normal vestibular *** were divided into two groups;Group A:below 50 years of age and Group B:50 years of age or *** was presented at frequencies 0.02,0.04,0.08,0.16,0.32,0.64 Hz with a peak velocity of 60°/*** was performed using a maximum velocity of 100°/s with acceleration and deceleration of 200°/*** subjects were tested twice to assess ***:Study participants ranged in age from 20 to 67 *** group A,the mean age was30.92±7.31 and 55.36±4.61 for group *** significant differences were found in SHAT parameters between the two *** well,there was no significant difference in VST per-rotatory time constant,however,post-rotatory time constant was significantly longer for Group B(P value<0.05).Intraclass correlation coefficient(ICC)values showed moderate to good reliability(ICC 0.5800.818)for SHAT parameters for the lower frequencies and indicated moderate reliability for VST time constant(ICC 0.5090.652).Conclusions:Age has no significant effect on the parameters of SHAT and ***-retest reliability is generally good for both tests.

关键词： Rotatory chair testing Sinusoidal harmonic acceleration test Velocity step test Age effect Test-retest reliability

EXPERIENCE WITH THERMOMECHANICAL FATIGUE UNDER SERVICE-TYPE LOADING

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 407-413页

作者： A.Scholz A.Schmidt A.samir C.Berger Institute of Materials Technology Darmstadt University of Technology Grafenstrasse 2 D-64283 Darmstadt GermanyInstitute of Materials Technology Darmstadt University of Technology Grafenstrasse 2 D-64283 Darmstadt GermanyInstitute of Materials Technology Darmstadt University of Technology Grafenstrasse 2 D-64283 Darmstadt GermanyInstitute of Materials Technology Darmstadt University of Technology Grafenstrasse 2 D-64283 Darmstadt Germany

The thermomechanical fatigue behaviour of different high temperature alloys has been investigated and is under investigation respectively. The creep-fatigue behaviour of heat resistant steels was investigated by long-term service-type strain cycling tests simulating thermomechanical fatigue (TMF-) loading conditions at the heated surface of e.g. turbine rotors. Single-stage as well as three-stage cycles leads to similar results at the application of the damage accumulation rule. Life prediction which simulates typical combinations of cold starts, warm starts and hot starts has been established successfully for isothermal service-type loading and will be exceeded for thermomechanical loading. Long-term thermomechanical fatigue testing of Thermal Barrier Coating systems show typical delamination damage. An advanced TMF cruciform testing system enables complex multiaxial loading.

关键词： thermomechanical fatigue multi-stage service-type loading thermal barrier coating cruciform testing long-term experiment

Implementing Effective Learning with Ubiquitous Learning Technology During Coronavirus Pandemic

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Computer Systems Science & Engineering 2022年第1期40卷 389-404页

作者： Hosam F.El-Sofany samir A.El-Seoud King Khalid University AbhaKingdom of Saudi Arabia Cairo Higher Institute for Engineering Computer Science and ManagementCairoEgypt British University in Egypt—BUE Faculty of Informatics and Computer ScienceCairoEgypt

Ubiquitous computing supports U-learning to develop and implement a new educational environment that provides effective and interactive learning to students wherever they *** study aims to present a qualitative evaluation for using U-learning instead of traditional education to avoid the spread of the Coronavirus *** authors introduce a UTAUT(Unified Theory of Acceptance and Use of Technology)model to assess the capability of the given factors that are expected to affect the learners’intention and behavior for accepting the U-learning technology for full *** research study shows a promising impact on the use of U-learning apps for implementing their learning activities in both the present and coming *** study also presents the descriptive statistics that affect the students’answers by using U-learning while implementing learning assignments including exams,projects,forums,essays,presentations,and *** research experiments demonstrate both the composite reliability(CR)and the average variance extracted(AVE)of the presented *** experimental results have shown that(1)the factor loadings≥0.75,CR≥0.9,and AVE≥0.75,which present appropriate proof for the validity and reliability of the proposed model,and(2)the total average of students that accept the U-learning is 82.99%,and who disagree is 8.13%,while who neither agree nor disagree is 6.44%.

关键词： Ubiquitous learning U-learning E-learning M-learning COVID-19 pandemic coronavirus UTAUT model

Management of alcoholic hepatitis:Current concepts

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World Journal of Hepatology 2012年第12期4卷 335-341页

作者： Hetal A Karsan samir Parekh Atlanta Gastroenterology Associates Emory UniversityAtlantaGA 30342United States Emory University Liver Transplant Program AtlantaGA 30322United States

Alcoholic hepatitis is a devastating form of acute liver injury seen in chronic alcohol abusers with significant morbidity and *** is a multisystem disease that is precipitated by ingesting large quantities of alcohol with genetic and environmental factors playing a *** criteria have been developed to predict disease severity and these criteria can serve as indicators to initiate medical *** therapy remains abstinence and supportive care,as continued alcohol abuse is the most important risk factor for disease *** cornerstone of supportive care remains aggressive nutritional support,and although acute alcoholic hepatitis has been extensively studied,few specific medical therapies have been *** remain the most effective medical therapy available in improving short term survival in a select group of patients with alcoholic hepatitis;however,the long-term outcome of drug therapies is still not entirely clear and further clinical investigation is *** liver transplantation for acute alcoholic hepatitis have demonstrated promising results,this practice remains controversial and has not been advocated universally,with most transplant centers requiring a prolonged period of abstinence before considering *** liver support devices,although still experimental,have been developed as a form of liver support to give additional time for liver *** have the potential for a significant therapeutic option in the future for this unfortunately dreadful disease.

关键词： Alcholic hepatitis Acute liver injury Abstinence Nutrition Corticosteroids Transplantation Extracorporeal liver support

The Dynamics and Control of the Fractional Forms of Some Rational Chaotic Maps

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Journal of Systems Science & Complexity 2020年第3期33卷 584-603页

作者： OUANNAS Adel KHENNAOUI Amina-Aicha BENDOUKHA samir WANG Zhen PHAM Viet-Thanh Laboratory of Mathematics Informatics and Systems(LAMIS)University of Larbi TebessiTebessa 12002Algeria Department of Mathematics and Computer Sciences University of Larbi Ben M'hidiOum El BouaghiAlgeria Department of Electrical Engineering College of EngineeringYanbuTaibah UniversitySaudi Arabia Shaanxi Engineering Research Center of Controllable Neutron Source School of ScienceXijing UniversityXi'an 710123China Faculty of Electrical and Electronic Engineering Phenikaa Institute for Advanced Study(PIAS)Phenikaa UniversityYen NghiaHa Dong districtHanoi 100000Vietnam Phenikaa Research and Technology Institute(PRATI) A&A Green Phoenix Group167 Hoang NganHanoi 100000Vietnam

This paper proposes three fractional discrete chaotic systems based on the Rulkov,Chang,and Zeraoulia–Sprott rational *** dynamics of the proposed maps are investigated by means of phase plots and bifurcations *** stabilization schemes are proposed for each of the three maps and the convergence of the states is established by using the Lyapunov ***,a combination synchronization scheme is proposed whereby a combination of the fractional Rulkov and Chang maps is synchronized to the fractional Zeraoulia-Sprott *** results are used to confirm the findings of the paper.

关键词： Fractional discrete chaos fractional rational maps stabilization synchronization

Improving of photocatalytic activity of barium ferrate via bismuth and copper co-doping for degradation of paracetamol under visible light irradiation

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Journal of Environmental Sciences 2022年第2期34卷 331-342页

作者： Hussien Ahmed Abbas Rabab Ahmed Nasr Rose-Noelle Vannier Tarek samir Jamil Inorganic Chemistry Department National Research CentreCairo 12622Egypt Water Pollution Control Department National Research CenterCairo 12622Egypt Univ.Lille CNRSCentrale LilleENSCLUniv.ArtoisUMR 8181Unite de Catalyse et Chimie du Solide(UCCS)Lille 59000France

Nanosized Ba_(1-x)Bi_(x)Fe_(1-x)Cu_(x)O_(3)(12–50 nm)with x values of 0,0.01,0.05,and 0.1 system was prepared using the Pechini ***,morphological,surface and optical characterizations were performed for the prepared *** phase was the predominant phase for the undoped BaFeO_(3)and Bi and Cu co-doped BaFeO_(3)*** phases of monoclinic Ba_(2)Fe_(2)O_(5),orthorhombic BaFe_(2)O_(4)and orthorhombic BaCO_(3)were identified for all the prepared ***_(0.95)Bi_(0.05)Fe_(0.95)Cu_(0.05)O_(3)sample has the lowest band gap(2.43 e V).98.1%paracetamol removal was achieved with 0.75 g/L of Ba_(0.95)Bi_(0.05)Fe_(0.95)Cu_(0.05)O_(3)at pH9 after 120 *** paracetamol degradation follows the pseudo first-order ***·is the main oxidative species responsible for the paracetamol *** chromatography–mass spectrometry(GC–MS)analysis was performed at the end of the photocatalytic degradation experiment under optimum operating condition using Ba_(0.95)Bi_(0.05)Fe_(0.95)Cu_(0.05)O_(3)to explain the reaction mechanism and identify the intermediate by-products which is confirmed by ultraviolet/visible(UV/Vis)spectroscopy study at different reaction times.

关键词： Ba_(1-x)Bi_(x)Fe_(1-x)Cu_(x)O_(3) Photocatalytic degradation Nanomaterials Paracetamol

ON HYPERSTABILITY OF THE BIADDITIVE FUNCTIONAL EQUATION

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Acta Mathematica Scientia 2017年第6期37卷 1727-1739页

作者： Iz-iddine EL-FASSI Janusz BRZDEK Abdellatif CHAHBI samir KABBAJ Department of Mathematics Faculty of SciencesIbn Tofail UniversityBP 133KenitraMorocco Department of Mathematics Pedagogical UniversityPodchorazych 230-084 KrakowPoland

We present results on approximate solutions to the biadditive equationf（x＋y,z-w）＋f（x-y,z＋w）=2f（x,z）-2f（y,w）on a restricted domain. The proof is based on a quite recent fixed point theorem in some function spaces. Our main results state that, under some weak natural assumptions, functions satisfying the equation approximately （in some sense） must be actually solutions to it. In this way we obtain inequalities characterizing biadditive mappings and inner product spaces. Our outcomes are connected with the well known issues of Ulam stability and hyperstability.

关键词： hyperstability Ulam stability biadditive functional equation fixed point the-orem characterization of inner product space

Comparison of Effect of Intermediate Segment and Short Segment Pedicle Screw Fixation for Surgical Treatment of Thoracolumbar Fracture

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Comparison of Effect of Intermediate Segment and Short Segme...

作者： samir Karki 吉林大学

学位级别：硕士

PURPOSE: Surgical treatment in the case of thoracolumbar fracture is very *** fixation is most frequently used compared to the anterior fixation;however, thenumber of levels to be instrumented still remains a matter of debate. We want to compare thesurgical outcomes of short segment and intermediate segment posterior fixation forthoracolumbar burst fracture in order to provide a theoretical basis for the better treatment ofthoracolumbar burst fracture.MATERIALS and METHODS: A total of36patients who had a single level Type A-3(AO classification) burst fracture between T11to L2were selected and were managedusing posterior instrumentation and fusion, no laminectomy or discectomy procedure wasdone. They were divided into two groups as follows;Group I (n=16) included patients whowere operated by intermediate segment posterior fixation (ISPF) that is two vertebrae aboveand one vertebrae below the fracture vertebrae or one vertebrae above and two vertebraebelow the fracture level, Group II (n=20) included patients who were operated by shortsegment posterior fixation (SSPF) that is one vertebrae above and one vertebrae below thefracture vertebrae. The mean follow up period was11months ranging from6months to15months. The outcomes were analyzed in terms of Cobb’s Angle (CA), Sagittal Index (SI)and Anterior Body Height (ABH).RESULT: Both short segment and intermediate segment posterior transpedicular fixationhave good outcomes in the treatment of thoracolumbar fractures in terms of correction ofCobb’s angle, Sagittal index and Anterior body height. A statistically significant differencebetween the two study groups was noted for the immediate post op of the Cobb’s angle(p=0.031), sagittal index (p=0.048) as well as on the Cobb’s angle (p=0.024) and anteriorbody height (p=0.045) on the final follow up.CONCLUSION: Both short segment and intermediate segment posterior transpedicularfixation are able for correcting the cobb angle, sagittal index, and

关键词： Thoracolumbar burst fracture posterior instrumentation intermediatesegment fixation short segment fixation

Interval oscillation criteria for forced Emden-Fowler functional dynamic equations with oscillatory potential

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Science China Mathematics 2013年第3期56卷 561-576页

作者： ANDERSON Douglas R. SAKER samir H. Department of Mathematics and Computer Science Concordia College Department of Mathematics Faculty of Science Mansoura University

Interval oscillation criteria are established for a second-order functional dynamic equation of Emden-Fowler type with oscillatory potential by applying Riccati and generalized Riccati techniques. The results represent further improvements on those given even for differential and difference equations. Some examples are considered to illustrate the main results.

关键词： oscillation forced dynamic equations time scales functional equations Riccati technique