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Communications in Theoretical Physics 2024年第4期76卷 22-31页

作者： Yusry O el-dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The time-delayed fractal Van der Pol–Helmholtz–Duffing(VPHD)oscillator is the subject of this paper,which explores its mechanisms and highlights its stability *** time-delayed technologies are currently garnering significant attention,the focus of this research remains crucially relevant.A non-perturbative approach is employed to refine and set the stage for the system under *** innovative methodologies introduced yield an equivalent linear differential equation,mirroring the inherent nonlinearities of the ***,the incorporation of quadratic nonlinearity into the frequency formula represents a cutting-edge *** analytical solution's validity is corroborated using a numerical *** conditions are ascertained through the residual Galerkin ***,it is observed that the delay parameter,in the context of the fractal system,reverses its stabilizing influence,impacting both the amplitude of delayed velocity and the *** analytical solution's precision is underscored by its close alignment with numerical ***,the study reveals that fractal characteristics emulate damping *** its applicability across diverse nonlinear dynamical systems,this non-perturbative approach emerges as a promising avenue for future research.

关键词： Van der Pol-Helmholtz-Duffing oscillator fractal space time-delay non-perturbative approach stability analysis el-dib's frequency formula

Evidence-based medicine: An update on treatments for peritoneal dialysis-related peritonitis

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World Journal of Nephrology 2015年第2期4卷 287-294页

作者： Pasqual Barretti Joo Vitor Pereira Doles Douglas Gonalves Pinotti regina Paolucci el dib Department of Internal Medicine Botucatu Medical SchoolUNESP Botucatu Medical School UNESP Department of Anesthesiology Botucatu Medical SchoolUNESP

Peritonitis continues to be a major complication of peritoneal dialysis （PD）, and adequate treatment is crucial for a favorable outcome. There is no consensus regarding the optimal therapeutic regimen, and few prospective controlled studies have been published. The objectiveof this manuscript is to review the results of PD peritonitis treatment reported in narrative reviews, systematic reviews, and proportional meta-analyses. Two narrative reviews, the only existing systematic review and its update published between 1991 and 2014 were included. In addition, we reported the results of a proportional meta-analysis published by our group. Results from systematic reviews of randomized control trials （RCT） and quasi-RCT were not able to identify any optimal antimicrobial treatment, but glycopeptide regimens were more likely to achieve a complete cure than a first generationcephalosporin. Compared to urokinase, simultaneous catheter removal and replacement resulted in better outcomes. Continuous and intermittent IP antibiotic use had similar outcomes. Intraperitoneal antibiotics were superior to intravenous antibiotics in reducing treatment failure. In the proportional meta-analysis of RCTs and the case series, the resolution rate （86%） of ceftazidime plus glycopeptide as initial treatment was signifcantly higher than frst generation cephalosporin plus aminoglycosides （66%） and glycopeptides plus aminoglycosides （75%）. Other comparisons of regimens used for either initial treatment or treatment of gram-positive rods or gram-negative rods did not show statistically significant differences. The superiority of a combination of a glycopeptide and a third generation cephalosporin was also reported by a narrative review study published in 1991, which reported an 88% resolution rate.

关键词： Peritonitis Peritoneal dialysis Antibiotic Treatment

Renal Function after Major Uro-Oncologic Surgery and Dexmedetomidine Infusion

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Open Journal of Anesthesiology 2013年第8期3卷 356-362页

作者： Marcus Vinicius M. Novaes Paulo Sergio G. Lavinas Grace Haber D. Pires Ana Claudia G. de Carvalho Renata M. B. Lopes regina el dib Paulo do Nascimento Jr. Cancer Institute (INCA) Rio de Janeiro Brazil Department of Anesthesiology Univ Estadual Paulista (UNESP) Botucatu Brazil

Objective: Acute kidney injury in major surgery is associated with increased postoperative mortality. This study aimed to evaluate renal function after major urologic surgery and intraoperative dexmedetomidine infusion. Methods: Thirty oncologic patients with normal renal function scheduled for prostatectomy or nephrectomy, anesthetized with combined epidural and general anesthesia, were randomized to receive either intraoperative blind infusion of dexmedetomidine (Dexmedetomidine Group, n = 15, 0.5 μg/kg load dose plus 0.7 μg/kg/h) or 0.9% saline (Control Group, n = 15) until the end of surgery. Intraoperative and cumulative 24-hour diuresis, serum creatinine (SCr), calculated creatinine clearance (ClCr) and serum cystatin C (SCys) at postoperative days 1, 2 and 3 and 2 weeks after surgery were evaluated. Results: Mean ± standard deviation values for intraoperative diuresis in Dexmedetomidine and Control Groups were 566 ± 396 mL and 298 ± 153 mL, respectively (p = 0.014). Cumulative 24-hour diuresis in Dexmedetomidine and Control Groups was 1947 ± 266 mL and 1748 ± 237 mL, respectively (p = 0.91). Mean values of SCr, ClCr and SCys were not significantly different from their baseline values in both groups and no significant differences were seen between groups at any moment for two weeks (p > 0.05). Conclusion: According to the doses used in this study, despite an intraoperative increase in diuresis, intraoperative infusion of dexmedetomidine did not influence renal performance up to two weeks after major uro-oncologic surgery, as evaluated by SCr, ClCr and SCys.

关键词： Dexmedetomidine Renal Function Nephrectomy Prostatectomy Epidural General Anesthesia

A scalable blockchain-based scheme for traffic-related data sharing in VANETs

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Blockchain(Research and Applications) 2022年第3期3卷 109-121页

作者： el-hacen Diallo Omar dib Khaldoun Al Agha UniversitéParis-Saclay CNRSLaboratoire Interdisciplinaire des Sciences du Numérique91190Gif-sur-YvetteFrance Department of Computer Science Wenzhou-Kean UniversityWenzhou325015China

Recent advances in wireless technology and embedded systems enable vehicles to share relevant traffic-related data to improve the transportation Quality-of-Service(QoS).However,due to the ubiquitousness of cyber-attacks,it is challenging to ensure the integrity of the data collected from *** paper proposes a novel architecture for road traffic events management in Vehicular Ad hoc NETworks(VANETs)relying on a permissioned *** also introduces the concept of micro-transactions to minimize communication and storage *** simulations,a rigorous performance evaluation of the proposed approach was conducted,and the micro-transactions effectiveness was *** addition,a comparison with close works in the literature was *** proposed scheme ensures road traffic records integrity and traceability,and simulation results on the considered scenarios showed good performance.

关键词： Vehicular ad hoc NETworks(VANETs) Blockchain Consensus mechanisms Practical byzantine fault tolerance(PBFT) Data sharing

Damped Mathieu Equation with a Modulation Property of the Homotopy Perturbation Method

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Sound & Vibration 2022年第1期56卷 21-36页

作者： Yusry O.el-dib Nasser S.elgazery Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

In this article,the main objective is to employ the homotopy perturbation method(HPM)as an alternative to classical perturbation methods for solving nonlinear equations having periodic *** a simple example,the nonlinear damping Mathieu equation has been *** this investigation,two nonlinear solvability conditions are *** of them was imposed in the first-order homotopy perturbation and used to study the stability behavior at resonance and non-resonance *** next level of the perturbation approaches another solvability condition and is applied to obtain the unknowns become clear in the solution for the firstorder solvability *** approach assumed here is so significant for solving many parametric nonlinear equations that arise within the engineering and nonlinear science.

关键词： Damped Mathieu Equation parametric nonlinear oscillator resonance instability homotopy perturbation method(HPM)

An efficient approach to solving fractional Van der Pol-Duffing jerk oscillator

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Communications in Theoretical Physics 2022年第10期74卷 50-59页

作者： Yusry O el-dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The motive behind the current work is to perform the solution of the Van der Pol–Duffing jerk oscillator,involving fractional-order by the simplest *** effective procedure has been introduced for executing the fractional-order by utilizing a new method without the perturbative *** approach depends on converting the fractional nonlinear oscillator to a linear oscillator with an integer order.A detailed solving process is given for the obtained oscillator with the traditional system.

关键词： Van der Pol oscillator Duffing jerk oscillator fractional oscillator non-perturbative approach numerical simulation

Hypoglycaemic effect of Berberis vulgaris *** normal and streptozotocin-induced diabetic rats

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Asian Pacific Journal of Tropical Biomedicine 2011年第6期1卷 468-471页

作者： Nawel Meliani Mohamed el Amine dib Hocine Allali Boufeldja Tabti Laboraloire des Substances Naturelles et Bioactives (LASNABIO) Departement de Chimie Faculte des SciencesUniversite Aboubekr Belkaid BP 119

Objective:To achieve a primary pharmacological screening contained in the aqueous extract of Berberis vulgaris(***) and to examine the hypoglycaemic effect and biochemical parameters of aqueous and saponins extract on groups of rats rendered diabetic by injection of ***:The phytochemicol tests to detect the presence of different compounds were based on the visual observation of color change or formation of precipitate after the addition of specific *** was induced in rats by intraperitoneal(i.p.) injection of streptozotocin(STZ) at a dose of 65 mg/kg *** fasting blood glucose levels were estimated by glucose oxidase-peroxidase reactive strips(Dextrostix,Bayer Diagnostics).Blood samples were taken by cutting the tip of the *** cholesterol and serum triglycerides were estimated by enzymatic DHBS colorimetric ***:Administration of 62.5 and 2S.0 mg/kg of saponins and aqueous extract respectively in normal rats group shows a significant hypoglycemic activity(32.33%and 40.17%respectively) during the first ***,diabetic group treated with saponin extract produced a maximum fall of 73.1%and 76.03%at day 1 and day 21 compared to the diabetics ***,blood glucose levels of the diabetic rats treated with aqueous extract showed decrease of 78.79%on the first day and the effect remains roughly constant during 3 week. Both extracts also declined significantly biochemical parameters(20.77%-49.00%).The control in the loss of body weight was observed in treated diabetic rats as compared to diabetic controls. Conclusions:These results demonstrated significant antidiabetic effects and showed that serum cholesterol and serum triglycerides levels were decreased,significantly,consequently this plant might be of value in diabetes treatment.

关键词： Berberis vulgaris L. Antidiabetic activity Streptozotocin-induced diabetes Saponins Aqueous extract Photochemical screening Hypoglycaemic effect Biochemical parameters Cholesterol Triglycerides Glucose oxidase-peroxidase Colorimetric method

An innovative technique to solve a fractal damping Duffing-jerk oscillator

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Communications in Theoretical Physics 2023年第5期75卷 3-11页

作者： Yusry O el-dib Nasser S elgazery Youmna M Khattab Haifa A Alyousef Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt Department of Physics College of SciencePrincess Nourah bint Abdulrahman UniversityPO Box 84428Riyadh 11671Saudi Arabia

The idea of the present article is to look into the nonlinear dynamics and vibration of a damping Duffing-jerk oscillator in fractal space exhibiting the non-perturbative *** a new analytical technique,namely,the modification of a He’s fractal derivative that converts the fractal derivative to the traditional derivative in continuous space,this study provides an effective and easy-to-apply procedure that is dependent on the He’s fractal derivative *** analytic approximate solution has a significant match with the results of the numerical simulation as the fractal parameter is very closer to unity,which proves the reliability of the *** behavior is discussed and illustrated *** new powerful analytical tools are developed in an attempt to obtain effective analytical tools,valid for any fractal nonlinear problems.

关键词： modification of He’s fractal derivative fractal duffing-jerk vibration stability analysis non-perturbative approach damping nonlinear fractal system

Geochemical assessment, mixing behavior and environmental impact of thermal waters in the Guelma geothermal system,Algeria

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Acta Geochimica 2019年第5期38卷 683-702页

作者： Foued Bouaicha Henia dib Oualid Bouteraa Nabil Manchar Kamel Boufaa Nabil Chabour Abdeslam Demdoum Department of Applied Biology Universite des Freres Mentouri Constantine 1025000 ConstantineAlgeria Department of Geology Universite des Freres Mentouri Constantine 1025000 ConstantineAlgeria Laboratory of Geology and Environment (LGE) Uni versite des Freres Mentouri Constantine 1ConstantineAlgeria Department of Geology Sciences University of Larbi Ben M'hidi04000 Oum El BouaghiAlgeria Department of Earth Sciences University of Setif 119000 SetifAlgeria

A study of thirteen geothermal springs located in the geothermal field of Guelma,northeastern Algeria,was *** were collected during the period between January 2014 and February *** processes responsible for the chemical composition of thermal and mineralized water were *** hydrochemical analysis shows that the thermal waters are characterized by the presence of two different chemical facies,the first type SO4-Ca in the east,west and south of Guelma,the second type HCO3-Ca in the *** analysis also attributed to sodium,chlorides,and sulfates to an evaporitic terrigenous origin by the molar ratio Sr2+/Ca2+.The thermal spring waters from Guelma geothermal system have a meteoric origin,and all samples are immature with strong mixing between hot and shallow waters with 19-38.5%rate of *** silica geothermometer shows that these thermal waters have a temperature varying from 84 to 122℃and that the water came from a depth of 2100-3000 m through a fault system that limits the pullapart basin of *** environmental effluent from thermal spas could pollute in both the irrigation and drinking waters,and which imposes danger on the health of the inhabitants of the region.

关键词： Geochemistry Geothermometry Mixing Thermal effluents Guelma Algeria

Phytotoxic effect of Sesbania virgata(Cav.) *** seeds of agronomic and forestry species

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Journal of Forestry Research 2015年第2期26卷 339-346页

作者： Vera Lygia el Id Bárbara Vale da Costa Daiane Salete Broch Mignoni Marina Belloni Veronesi Kelly Simoes Marcia regina Braga Nelson Augusto dos Santos Junior Seed Department Institute of Botany Plant Physiology and Biochemistry Department Institute of Botany

Sesbania virgata（Cav.） *** a pioneer species native to South America able to release allelochemicals that affect germination and development of other plant *** aim of this work was to evaluate the allelopathic effect of *** on the germination and development of co-occurring species from gallery forest and on agronomic *** forest native species,Enterolobium contortisiliquum（Vell.） Morong and Sapindus saponaria L.,and two agronomic species（these as control）,Oryza sativa *** Solanum lycopersicum *** used in the lab and greenhouse assays with seeds and leaf extracts of *** species were more affected than native species when co-germinated with seeds of *** germination percentage and speed germination index of the agronomic species were reduced in both in vitro and greenhouse *** the same assays,the seeds of native species showed no significant differences in the parameters ***,the initial growth of the four species assayed was affected,with reduction in plant length and shoot diameter followed by significant reduction in plantlet shoot and root *** the assays with irrigation of *** leaf extracts,no significant inhibitory effects on germination were observed for all *** and shoot diameter of the native species were not affected by the leaf extracts,nor were fresh and dry ***,these parameters increased in the agronomic species as they were irrigated with leaf *** on our data we conclude that seed leachates of *** affect germination and seedling development of other species,suggesting that its invasive behavior is due mainly to seed *** with less pronounced effects on native species,allelopathy of *** might also influence Interspecific competition in its natural environment.

关键词： Allelochemicals Allelopathy Catechin Fabaceae Gallery forest