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Numerical Treatments for Crossover Cancer Model of Hybrid Variable-Order Fractional Derivatives

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Computer Modeling in Engineering & sciences 2024年第8期140卷 1619-1645页

作者： nasser sweilam seham Al-Mekhlafi Aya Ahmed Ahoud Alsheri Emad Abo-Eldahab Mathematics Department Faculty of ScienceCairo UniversityGiza12613Egypt Mathematics Department Faculty of EducationSana’a UniversitySana’a1247Yemen Mathematics Department Faculty of ScienceHelwan UniversityCairo11795Egypt Department of Mathematics College of ScienceUniversity of BishaAl Namas67398-5644Saudi Arabia

In this paper,two crossover hybrid variable-order derivatives of the cancer model are ***ünwald-Letnikov approximation is used to approximate the hybrid fractional and variable-order fractional *** existence,uniqueness,and stability of the proposed model are *** Bashfourth’s fifth-step method with a hybrid variable-order fractional operator is developed to study the proposed *** studies with generalized fifth-order Runge-Kutta method are *** examples and comparative studies to verify the applicability of the used methods and to demonstrate the simplicity of these approximations are *** have showcased the efficiency of the proposed method and garnered robust empirical support for our theoretical findings.

关键词： Cancer diseases hybrid variable-order fractional derivatives adams bashfourth fifth step generalized fifth order Runge-Kutta method

Refraction characteristics of phononic crystals

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Acta Mechanica sinica 2015年第4期31卷 481-493页

作者： sia nemat-nasser Department of Mechanical and Aerospace Engineering University of California

some of the most interesting refraction prop- erties of phononic crystals are revealed by examining the anti-plane shear waves in doubly periodic elastic composites with unit cells containing rectangular and/or elliptical multi- inclusions. The corresponding band structure, group velocity, and energy-flux vector are calculated using a powerful mixed variational method that accurately and efficiently yields all the field quantities over multiple frequency pass-bands. The background matrix and the inclusions can be anisotropic, each having distinct elastic moduli and mass densities. Equifrequency contours and energy-flux vectors are read- ily calculated as functions of the wave-vector components. By superimposing the energy-flux vectors on equifrequency contours in the plane of the wave-vector components, and supplementing this with a three-dimensional graph of the corresponding frequency surface, a wealth of information is extracted essentially at a glance. This way it is shown that a composite with even a simple square unit cell con- taining a central circular inclusion can display negative or positive energy and phase velocity refractions, or simply performs a harmonic vibration （standing wave）, depending on the frequency and the wave-vector. Moreover, that the same composite when interfaced with a suitable homoge- neous solid can display：（1） negative refraction with negative phase velocity refraction; （2） negative refraction with pos- itive phase velocity refraction; （3） positive refraction with negative phase velocity refraction; （4） positive refraction with positive phase velocity refraction; or even （5） completereflection with no energy transmission, depending on the fre- quency, and direction and the wavelength of the plane-wave that is incident from the homogeneous solid to the interface. For elliptical and rectangular inclusion geometries, analyti- cal expressions are given for the key calculation quantities. Expressions for displacement, velocity, linear m

关键词： Doubly periodic composites - Phononiccrystals Band structure Group and energy-flux vectors

Transcranial Direct Current stimulation: Effects on Motor and Non-Motor symptoms of Parkinson’s Disease

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Journal of Behavioral and Brain science 2024年第5期14卷 135-160页

作者： Fayda Protásio Carlos Alberto Bezerra Tomaz Joaquim Brasil-Neto Pedro Brandão nasser Allam Maria Clotilde Henriques Tavares Laboratory of Neuroscience and Behavior Department of Physiological Sciences Institute of Biology University of Braslia Braslia Brazil Master Program in Environment University CEUMA So Lus MA and Faculty of Medicine Euro-American University Center-UNIEURO Braslia Brazil Faculty of Medicine Euro-American University Center-UNIEURO Braslia Brazil NA Neurologistas Associados Braslia Brazil

Introduction: In the last thirty years, brain neuromodulation techniques have been used as an alternative to pharmacological treatment of neurological disorders. Parkinson’s disease (PD) is a neurodegenerative disorder leading to bradykinesia, rest tremor, postural changes, and non-motor symptoms such as depression, anxiety, sleep disorders, pain, and cognitive decline that compromises executive functions (EFs), responsible for the orderly execution of behaviors and tasks of daily life and intentional and directed actions. To this date, a few studies with transcranial direct current stimulation (tDCs) have shown beneficial effects in PD patients concerning specific motor and non-motor symptoms, targeting the motor cortex and/or prefrontal regions. Objective: The main objective of this study was to evaluate the effects of left prefrontal tDCs across a broad spectrum of motor and non-motor symptoms of PD using established validated scales. Method: single-blind randomized clinical trial with 18 volunteers with PD, aged between 45 and 80 years (66.1 ± 9.65), who met inclusion and exclusion criteria. Participants were submitted to assessments of motor and non-motor functions employing psychometric scales and tests to evaluate EFs and were randomly divided into two groups: control (sham stimulation) and experimental (active stimulation). All participants were involved in three separate tDCs sessions. The anode was positioned over the left dorsolateral prefrontal cortex and the cathode over the right supraorbital region, with a direct current intensity of 2 mA, lasting 20 minutes. At the end of the three sessions, all participants were reassessed. Results: significant effects of tDCs on non-motor functions were observed for cognition (verbal fluency of actions, clock copy test, appointment by visual confrontation, and verbal memory with immediate free recall) and subjective assessment of sleep quality (overall restlessness and discomfort in the arms and legs at night, leg

关键词： Parkinson’s Disease Neuromodulation Transcranial Direct Current stimulation—tDCs Movement Disorders Mood sleep Cognition

Effect of a chemical reaction on magnetohydrodynamic boundary layer flow of a Maxwell fluid over a stretching sheet with nanoparticles

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Particuology 2016年第6期14卷 154-161页

作者： Ahmed A. Afify nasser s. Elgazery Department of Mathematics Faculty of Science Helwan University Ain Helwan PO Box 11795 Cairo Egypt Department of Mathematics Faculty of Education Ain Shams University Roxy Heliopolis Cairo Egypt

The influences of the convective boundary condition and heat generation/absorption on magnetohydro- dynamic boundary layer flow of a Maxwell fluid over a stretching surface in the presence of nanoparticles have been numerically investigated. In the model, the physical mechanisms responsible for Brownian motion and thermophoresis with a chemical reaction are considered. similarity equations are derived and then solved using the shooting method with the fourth-order Runge-Kutta integration scheme, The rates of heat and mass transfer are enhanced with a destructive chemical reaction and Blot number. The opposite influence is found with a generative chemical reaction in the presence of Brownian motion and the thermophoretic property.

关键词： Magnetohydrodynamics Nanoparticle Maxwell fluid Boundary layer flow Chemical reaction

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冯·卡门后期的工作和他留下的遗产

力学进展 2010年第1期40卷 99-109页

作者： s s Penner F A Williams P A Libby s.nemat-nasser 陶彩军加利福尼亚大学机械航空工程系中国科学院力学研究所

在早期出版的有关西奥多·冯·卡门的传记中,sears和sears(1979年)写到了他在德国哥廷根(1908年～1912年)、亚琛(1912年～1930年)以及他于1930年～1952年间在加州理工学院古根海姆航空实验室工作的情况.因此,本文只讨论他后期(即从1952... 详细信息

在早期出版的有关西奥多·冯·卡门的传记中,sears和sears(1979年)写到了他在德国哥廷根(1908年～1912年)、亚琛(1912年～1930年)以及他于1930年～1952年间在加州理工学院古根海姆航空实验室工作的情况.因此,本文只讨论他后期(即从1952年～1963年他逝世这一时期)的工作情况,也评述他的科学遗产,并确认继承冯.卡门风格从事气动热化学和相关领域研究的代表性研究机构和杰出研究人员.

关键词：气动热化学航空研究与发展咨询组国际宇宙航行学会

Effect of the degree of template removal from mesoporous silicate materials on their adsorption of heavy oil from aqueous solution

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Frontiers of Chemical science and Engineering 2014年第4期8卷 488-497页

作者： Farouq TWAIQ M.s. nasser sagheer A. ONAIZI Faculty of Engineering Computing and Science Swinbume University of Technology Kuching 93350 Malaysia Gas Processing Center College of Engineering Qatar University Doha P. O. Box 2713 Qatar school of Chemical Engineering and Advanced Materials Newcastle University Singapore 599489 Singapore school of Chemical Engineering and Advanced Materials Newcastle University Newcastle upon Tyne NE1 7RU UK

The key aim of this study is to evaluate the adsorption of heavy oil from aqueous solutions with different oil contents over mesoporous silicate materials having different surfactant template contents. The meso- porous silicate materials have been synthesized from tetraethylorthosilicate as a silica precursor and cetyltri- methylammonium bromide as a template using the sol-gel technique. Four samples were prepared by （1） totally removing the template using the calcination process, （2） partially removing the template via ethanol extraction, （3） partially removing the template via water extraction, and （4） keeping the template as synthesized, respectively. These four samples have been characterized using X-ray diffraction, nitrogen adsorption, thermal gravimetric ana- lysis and Fourier transformed infrared. The effect of the degree of template removal of these mesoporous materials for the oil removal has been investigated. The oil removal is inversely proportional to the surfactant content in the mesoporous material, being highest for the calcined sample but lowest for the as-synthesized sample. The kinetic of oil adsorption over the calcined material has been also studied and the data obtained fit well a second-order model.

关键词： adsorption heavy oil mesoporous silicatematerial kinetics template removal

A stochastic based approach for a new site classification method:application to the Algerian seismic code

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Earthquake Engineering and Engineering Vibration 2015年第4期14卷 663-681页

作者： Mohamed Beneldjouzi nasser Laouami Civil Engineering Faculty University of Sciences and Technology Houari Boumediene Earthquake Engineering Applied Research Center (CGs)

Building codes have widely considered the shear wave velocity to make a reliable subsoil seismic classification, based on the knowledge of the mechanical properties of material deposits down to bedrock. This approach has limitations because geophysical data are often very expensive to obtain. Recently, other alternatives have been proposed based on measurements of background noise and estimation of the H/V amplification curve. However, the use of this technique needs a regulatory framework before it can become a realistic site classification procedure. This paper proposes a new formulation for characterizing design sites in accordance with the Algerian seismic building code (RPA99/ver.2003), through transfer functions, by following a stochastic approach combined to a statistical study. For each soil type, the deterministic calculation of the average transfer function is performed over a wide sample of 1-D soil profiles, where the average shear wave (s-W) velocity, Vsub>ssub>, in soil layers is simulated using random field theory. Average transfer functions are also used to calculate average site factors and normalized acceleration response spectra to highlight the amplification potential of each site type, since frequency content of the transfer function is significantly similar to that of the H/V amplification curve. Comparison is done with the RPA99/ver.2003 and Eurocode8 (EC8) design response spectra, respectively. In the absence of geophysical data, the proposed classification approach together with micro-tremor measures can be used toward a better soil classification.

关键词： random field transfer function soil classification RPA99/ ver. 2003 EC8 site factor response spectrum

Development and course of heart failure after a myocardial infarction in younger and older people

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Journal of Geriatric Cardiology 2014年第1期11卷 1-12页

作者： Azam Torabi John GF Cleland Alan s Rigby nasser sherwi Department of Cardiology Castle Hill Hospital Hull York Medical School University of Hull Kingston upon Hull HU16 5JQ United Kingdom

Background Acute myocardial infarction （AMI） is a common cause of heart failure （HF）, which can develop soon after AMI and may persist or resolve or develop late. HF after an MI is a major source of mortality. The cumulative incidence, prevalence and resolution of HF after MI in different age groups are poorly described. This study describes the natural history of HF after AMI according to age. Methods Patients with AMI during 1998 were identified from hospital records. HF was defined as treatment of symptoms and signs of HF with loop diuretics and was considered to have resolved if loop diuretic therapy could be stopped without recurrence of symptoms. Patients were cate- gorised into those aged 〈 65 years, 65-75 years, and 〉 75 years. Results Of 896 patients, 311,297 and 288 were aged 〈 65, 65-75 and 〉75 years and of whom 24%, 57% and 82% had died respectively by December 2005. Of these deaths, 24 （8%）, 68 （23%） and 107 （37%） oc- curred during the index admission, many associated with acute HF. A further 37 （12%）, 63 （21%） and 82 （29%） developed HF that persisted until discharge, of whom 15, 44 and 62 subsequently died. After discharge, 53 （24%）, 55 （40%） and 37 （47%） patients developed I-IF for the first time, of whom 26%, 62% and 76% subsequently died. Death was preceded by the development of HF in 35 （70%）, 93 （91%） and 107 （85%） in aged 〈 65 years, 65-75 years and 〉75 years, respectively. Conclusions The risk of developing HF and of dying after an MI in- creases progressively with age. Regardless of age, most deaths after a MI are preceded by the development of HF.

关键词： Myocardial infarction Heart failure Age

Post-bulbar duodenal ulcer with anterior perforation with kissing ulcer and duodenocaval fistula:A case report and review of literature

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World Journal of Clinical Cases 2022年第25期10卷 9071-9077页

作者： nasser Alzerwi Department of surgery College of MedicineMajmaah UniversityRiyadh 66RiyadhSaudi Arabia

BACKGROUND A post-bulbar duodenal ulcer(PBDU)is an ulcer in the duodenum that is distal to the duodenal *** may coexist with a synchronous posterior ulcer in rare occurrences,resulting in a kissing ulcer(KU).Duodenocaval fistula(DCF)is another uncommon but potentially fatal complication related to *** is limited knowledge of the scenarios in which PBDU is complicated by KU and DCF *** sUMMARY A 22-year-old man was admitted to the emergency department with abdominal pain,stiffness,and *** X-ray showed pneumoperitoneum,suggesting a perforated *** revealed a KU with anterior perforation and a *** Kocherization,venorrahphy was used to control caval *** to the critical condition of the patient,only primary duodenorrahphy with gastrojejunostomy was performed as a damage control ***,later,the patient developed obstructive jaundice and leakage,and two additional jejunal perforations were *** to the poor condition of the duodenum and the involvement of the ampulla in the posterior ulcer,neither primary repair nor pancreatic-free duodenectomy and ampull-oplasty/ampullary reimplantation were considered viable;therefore,an emergency pancreaticoduodenectomy was performed,along with resection and anastomosis of the two jejunal *** patient had a smooth recovery after surgery and was discharged after 27 *** The timely diagnosis of PBDU and radical surgery can aid in the smooth recovery of patients,even in the most complex cases.

关键词： Duodenal ulcer Duodenocaval fistula Kissing ulcer Emergency Whipple’s surgery Case report