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Chinese Chemical Letters 2020年第7期31卷 1851-1854页

作者： Mustapha Ait el Had Abdelouahd Oukhrib mohamed Zaki Martine Urrutigoity Ahmed Benharref Remi Chauvin Laboratoire de Chimie Biomoleculaire Substances Naturelies et Reactivite(URAC 16)Faculte des Sciences SemlaliaUniversite Cadi AyyadB.P.2390MarrakechMorocco CNRS LCC(Laboratoire de Chimie de Coordination)BP 4409931077Toulouse Cedex 4France INP-enSIACET 4 allee Emile Monso31030Toulouse CedexFrance Universite de Toulouse UPSICT-FR 259931062Toulouse Cedex 9France

From a mixture of α-,β-and y-himachalenes extracted from waste wood of Atlas cedar(Cedrus atlantica),cadalene(1,6-dimethyl-4-isopropylnaphthalene)and iso-cadalene(1,6-dimethyl-3-isopropylnaphthalene)were produced in two steps with up to 71%±5%yield through the ar-himachalene intermediate using I2 and/or AlCl3 as *** selectivity is shown to sharply depend on the operating conditions:while I2/AlCl3 in dichloromethane promotes the formation of cadalene,the formation of iso-cadalene is favored in the presence of AlCl3 in *** bicyclic aromatic compounds were thus obtained through unique rearrangements involving sequential C—C bond cleavage/fo rmation and hydride transfer *** the absence of AlCl3 or I2,dihydrocurcumene was also found to be formed with up to 70%selectivity.A tentative mechanism is proposed and discussed.

关键词： Aromatic reactivity Cadalenes Dihydrocurcumene Himachalenes Rearrangements

Synthesis and comparative study of reactivities of δ-lactone,estor group and oxazinone ring in coumarin derivatives towards carbon or nitrogen nucleophiles

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Chinese Journal of Chemistry 1990年第5期8卷 469-473页

作者： el-KAFRAWy,A.F. SOLIMAN,A.y. BAKER,H.M. mohamed,F.K. el-KADy,M.y.Department of Chemistry,Faculty of Science,Ain Shams University and Faculty of Education at el-Fayoum,Cairo.Egypt Department of Chemistry Faculty of Science Ain Shams University and Faculty of Education at El‐Fayoum Cairo Egypt

Condensation of methyl 7-methylcoumarin-4-acetate(2)with primary amines and with an- thranilic acid gave 7-methyl-2-oxo-N-aryl-2H-[1]-benzopyran-4--acetamide(4a—d)and(7),respectively. Compound 7 underwent cyclization to give 2-(7-methyl-2-oxo-2H-[1]-benzopyran-4-yl)-methyl-4H-3,1- benzoxazin-4-one(3).The reaction of 3 with aromatic amines gave the corresponding quinazolone derivatives 5 which tautomerises to the thermodynamically more stable isomer 6,whereas its reaction with Grignard reagents and aromatic aldehydes gave 8a,8b,and 9a,9b,respectively.

关键词： Synthesis and comparative study of reactivities of lactone,estor group and oxazinone ring in coumarin derivatives towards carbon or nitrogen nucleophiles ring

Lie symmetry analysis and invariant solutions for(2+1) dimensional Bogoyavlensky-Konopelchenko equation with variable-coefficient in wave propagation

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Journal of Ocean engineering and Science 2022年第3期7卷 248-254页

作者： mohamed R.Ali Wen-Xiu Ma R.Sadat Department of Basic Science Faculty of Engineering at BenhaBenha UniversityBenhaEgypt Department of Mathematics Zhejiang Normal UniversityJinhua 321004ZhejiangChina Department of Mathematics King Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Mathematics and Statistics University of South FloridaTampaFL 33620-5700USA School of Mathematics South China University of TechnologyGuangzhou 510640China Department of Mathematics Zagazig Faculty of EngineeringZagazig UniversityZagazigEgypt

This work aims to present nonlinear models that arise in ocean *** are many models of ocean waves that are present in *** shallow water,the linearization of the equations requires critical conditions on wave capacity than it make in deep water,and the strong nonlinear belongings are *** use Lie symmetry analysis to obtain different types of soliton solutions like one,two,and three-soliton solutions in a(2+1)dimensional variable-coefficient Bogoyavlensky Konopelchenko(VCBK)equation that describes the interaction of a Riemann wave reproducing along the y-axis and a long wave reproducing along the x-axis in engineering and *** use the Lie symmetry analysis then the integrating factor method to obtain new solutions of the VCBK *** demonstrate the physical meaning of the solutions obtained by the presented techniques,the graphical performance has been demonstrated with some *** presented equation has fewer dimensions and is reduced to ordinary differential equations using the Lie symmetry technique.

关键词： Symmetry approach Solitons Partial differential equations The variable coefficients(2+1)-dimensional Bogoyavlensky Konopelchenko equation Nonlinear evolution equations

HCV Therapy Follow-up Fractionation (CTF2) by Intra-PBMC Nested RNA PCR Recognizes Early Virologic Response and Relapse

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Journal of Clinical and Translational Hepatology 2018年第2期6卷 147-154页

作者： mohamed Darwish Ahmed Abd Alla Saleh Ahmed elibiary Ramy Hassan elshaboury George y.Wu Reham M.Dawood Mostafa Kamel el Awady Tropical Medicine Department Faculty of MedicineAl-Azhar UniversityCairoEgypt Department of Pharmacy Massachusetts General HospitalBostonMAUSA Department of Medicine Division of Gastroenterology-HepatologyUniversity of Connecticut Health CenterHartfordCTUSA Department of Microbial Biotechnology National Research CenterCairoEgypt

Background and Aims:Sustained virologic response is evaluated by single-step reverse transcription(SRT)PCR as-say,which assesses hepatitis C virus(HCV)clearance from plasma but not from tissues such as peripheral blood mono-nuclear cells(PBMCs).Persistence of HCV RNA in PBMCs beyond end of treatment(EOT)is associated with *** goal was to measure intra-PBMC HCV RNA levels during oral antiviral therapy according to the HCV therapy follow-up fractionation(CTF2)***:Compen-sated chronic HCV patients(n=278 SRT-PCR positive)were scheduled to receive oral antiviral *** were followed-up by SRT and intra-PBMCs HCV RNA PCR at the end of the 2nd,6th,10th,14th,18th and 24th weeks to evaluate virus clearance from plasma and PBMCs,*** CTF2 protocol evaluated SRT and PBMC PCR status at each follow-up point for determining therapy continuation or inter-ruption to address cost ***:All patients tested negative by SRT PCR after therapy for 2 ***-cation of the CTF2 protocol revealed:a)increasing HCV clear-ance rate from 75.9%at the end of 10th week to 90.3%at the end of 24th week(pelimination rates diagnosed by PBMC HCV RNA PCR(?)compared to PBMC HCV RNA PCR(+)from the 6th to 24th week of treatment(py compared to the decline in positivity curves by PBMC PCR at the 6th-18th week compared to the 24th week(pent continuation;and e)solitary evaluation of EOT sustained HCV infection and relapses by PBMC HCV RNA(py elimination of serum and tissue(PBMC)HCV infection by oral antiviral therapy can be achieved and evaluated during a cost-effective CTF2 pro-tocol application.

关键词： CTF2 protocol HCV PBMCs PCR Cost-effectiveness

Existence and Upper Semi-Continuity of Random Attractors for Nonclassical Diffusion Equation with Multiplicative Noise on Rⁿ

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Journal of Applied Mathematics and Physics 2022年第12期10卷 3898-3919页

作者： Fadlallah Mustafa Mosa Abdelmajid Ali Dafallah Qiaozhen Ma Eshag mohamed Ahmed mohamed y. A. Bakhet Department of Mathematics and Physics Faculty of Education University of Kassala Kassala Sudan Department of Mathematics Faculty of Petroleum and Hydrology Engineering Alsalam University Al-Fulah Sudan College of Mathematics and Statistics Northwest Normal University Lanzhou China Faculty of Pure and Applied Sciences International University of Africa Khartoum Sudan School of Mathematics University of Juba Juba South Sudan

This paper is concerned with the existence and upper semi-continuity of random attractors for the nonclassical diffusion equation with arbitrary polynomial growth nonlinearity and multiplicative noise in H1(Rn). First, we study the existence and uniqueness of solutions by a noise arising in a continuous random dynamical system and the asymptotic compactness is established by using uniform tail estimate technique, and then the existence of random attractors for the nonclassical diffusion equation with arbitrary polynomial growth nonlinearity. As a motivation of our results, we prove an existence and upper semi-continuity of random attractors with respect to the nonlinearity that enters the system together with the noise.

关键词： Random Attractors Nonclassical Diffusion Equations Asymptotic Compactness Upper Semi-Continuity

Introduction of longstanding complicated sulcus intraocular lens into the intact capsular bag

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International Journal of Ophthalmology(english edition) 2021年第11期14卷 1779-1783页

作者： Fathy Fawzy Morkos Nader Fathy Fawzy mohamed el Bahrawy Rania Serag elkitkat Watany Research and Development Center Watany Eye HospitalCairo 11799Egypt Department of Ophthalmology Faculty of MedicineAin Shams UniversityCairo 11799Egypt

AIM:To propose a surgical technique that successfully reopened the empty and intact capsular bag after long periods of closure,with repositioning of the intraocular lens(IOL)from the ciliary sulcus into its preferred habitat inside the capsular ***:This is a case series,prospective,and interventional *** technique was first performed on an aphakic high myope with a closed posterior capsule for 18 ***,five patients with recurrently displaced sulcus IOLs for a range of 1 mo to 7 y were performed for the same *** surgery,identifying a"telltale white line"was an important landmark for detecting the site of major adhesions between the edge of the capsulorhexis and the posterior *** adhesions were freed using combined manual and viscoelastic dissection,followed by an easier freeing of adhesions along the whole capsular *** IOL was safely implanted,exchanged,or introduced from the sulcus into the fibrotic and closed capsular *** were followed up for a period ranging from 6 to 17 mo ***:All the patients experienced a remarkable improvement in their subjective *** lamp examination showed a postoperative centralized IOL in the *** follow up visits confirmed visual and IOL ***:This newly-introduced surgical technique facilitates the reopening of the empty yet intact capsular bag that has been closed by fibrotic proliferations,with secured implantation of the IOL inside the capsular *** with inadvertent implantation of IOLs into the ciliary sulcus,yet having an intact capsular bag,can benefit from this technique.

关键词： late in the bag technique displaced sulcus lOLs post cataract visual rehabilitation closed capsular lens bag

Modified aquila optimizer for forecasting oil production

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Geo-Spatial Information Science 2022年第4期25卷 519-535页

作者： Mohammed A.A.Al-qaness Ahmed A.Ewees Hong Fan Ayman Mutahar AlRassas mohamed Abd elaziz State Key Laboratory for Information engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina Systems University of Bisha Department of e-BishaKingdom of Saudi Arabia Department of Computer Damietta UniversityDamiettaEgypt School of Petroleum engineering China University of Petroleum(East China)QingdaoChina Department of Mathematics Faculty of ScienceZagazig UniversityZagazigEgypt Artificial Intelligence Research Center(AIRC) Ajman UniversityAjman 346United Arab Emirates Faculty of Computer Science&engineering Galala UniversitySuze 435611Egypt

Oil production estimation plays a critical role in economic plans for local governments and ***,many studies applied different Artificial Intelligence(AI)based meth-ods to estimate oil production in different *** Adaptive Neuro-Fuzzy Inference System(ANFIS)is a well-known model that has been successfully employed in various applica-tions,including time-series ***,the ANFIS model faces critical shortcomings in its parameters during the configuration *** this point,this paper works to solve the drawbacks of the ANFIS by optimizing ANFIS parameters using a modified Aquila Optimizer(AO)with the Opposition-Based Learning(OBL)*** main idea of the developed model,AOOBL-ANFIS,is to enhance the search process of the AO and use the AOOBL to boost the performance of the *** proposed model is evaluated using real-world oil produc-tion datasets collected from different oilfields using several performance metrics,including Root Mean Square Error(RMSE),Mean Absolute Error(MAE),coefficient of determination(R2),Standard Deviation(Std),and computational ***,the AOOBL-ANFIS model is compared to several modified ANFIS models include Particle Swarm Optimization(PSO)-ANFIS,Grey Wolf Optimizer(GWO)-ANFIS,Sine Cosine Algorithm(SCA)-ANFIS,Slime Mold Algorithm(SMA)-ANFIS,and Genetic Algorithm(GA)-ANFIS,***,it is compared to well-known time series forecasting methods,namely,Autoregressive Integrated Moving Average(ARIMA),Long Short-Term Memory(LSTM),Seasonal Autoregressive Integrated Moving Average(SARIMA),and Neural Network(NN).The outcomes verified the high performance of the AOOBL-ANFIS,which outperformed the classic ANFIS model and the compared models.

关键词： Oil production ANFIS opposition-based learning(OBL) Aquila Optimizer(AO) time series forecasting Tahe oilfield Sunah oilfield

Depression, Anxiety, Stress and Their Association with the Use of electronic Devices among Adolescents during the COVID-19 Pandemic

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International Journal of Mental Health Promotion 2022年第2期24卷 251-262页

作者： Ahmad y.Alqassim mohamed S.Mahfouz Mohammed M.Hakami Abdullah A.Al Faqih Ahmad A.Shugairi Malek R.Alsanosy Ahmed y.Rayyani AbdulAziz y.Albrraq Mohammed A.Muaddi Abdullah A.Alharbi Family and Community Medicine Department Faculty of MedicineJazan UniversityJazanSaudi Arabia

Background:Adolescence is a critical,multifactorial developmental *** the current pandemic of COVID-19,excessive using of electronic devices is a public health *** aim of this study is to investigate the relation-ship between depression and the use of electronic devices among secondary school children in Jazan,Saudi Arabia during the COVID-19 *** and Methods:The study is an observational,cross-sectional *** was collected using an anonymous online survey *** the Depression Anxiety Stress ***:A total of 427 participants were included in the *** prevalence of depression,anxiety,and stress in our study was 14.55%,12.01%,and 15.55%,*** the hours spent on electronic devices,13.6%of participants spent 1–4 h,43.6%spent 5–9 h,and 42.9%spent 10 h or more.86.7%reported an increase in their use of electronic devices during *** regression analysis revealed that the increase of Videogame Addiction Scale for Chil-dren is signiﬁcantly associated with an increase in Depression,Anxiety,and Stress scores(p-valueelectronic device use is a challenging issue among Saudi adolescents,and it has been associated with a negative impact on participants’mental *** study found a positive correlation between electronic device use and increased prevalence of mental health *** also found signiﬁcantly increased use of electronic device during the COVID-19 lockdown;hence,more mental issues were *** is obvious that electronic device use needs to be more controlled among *** can be achieved by involving those who are in this age group in other activities,like sports,which can reduce the time they spend on electronic device.

关键词： COVID-19 depression electronic devices adolescents public health environmental health

Validated spectrofluorimetric method for the determination of atorvastatin in pharmaceutical preparations

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Journal of Pharmaceutical Analysis 2012年第3期2卷 200-205页

作者： Mohie M.K.Sharaf el-Din Fathy M.M.Salama mohamed W.I.Nassar Khalid A.M.Attia mohamed M.y.Kaddah Department of Analytical Chemistry Faculty of PharmacyMansoura University Department of Analytical Chemistry Faculty of PharmacyAl-Azhar UniversityCairoEgypt Department of Analytical Chemistry Faculty of PharmacyMansoura UniversityMansouraEgypt

A rapid,sensitive and simple spectrofluorimetric method was developed for the estimation of *** this method,the native fluorescence characteristics of atorvastatin have been studied in both acidic and basic *** sensitivity was obtained with 5% acetic acid at 389 nm using 276 nm for *** analysis showed a good correlation coefficient(r=0.9995) between fluorescence intensity and concentration over the range of 1.5-4 mg/mL with detection limit of 0.012 mg/*** proposed method was successfully applied to the analysis of atorvastatin in pure and pharmaceutical dosage forms with average recovery of 100.2970.47%.The results were compared favorably with those of the reported method.

关键词： Spectrofluorimetric Atorvastatin Native fluorescence

Hepatic and gastrointestinal disturbances in Egyptian patients infected with coronavirus disease 2019: A multicentre cohort study

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World Journal of Gastroenterology 2021年第40期27卷 6951-6966页

作者： Hend Ibrahim Shousha Shimaa Afify Rabab Maher Noha Asem Eman Fouad Ehab F Mostafa Mohammed A Medhat Amr Abdalazeem Hazem elmorsy Miriam M Aziz Rateba S Mohammed mohamed Ibrahem Hassan elgarem Dalia Omran mohamed Hassany Bassem elsayed Ahmed y Abdelaziz mohamed el Kassas endemic Medicine Faculty of MedicineCairo UniversityCairo 11562Egypt Gastroenterology Department National Hepatology&Tropical Medicine Research InstituteCairo 11563Egypt Hepatology Department Students HospitalCairo UniversityGiza 12566Egypt The Public Health Department Faculty of MedicineCairo UniversityCairo 11562Egypt Egyptian Ministry of Health and PopulationCairo 11567Egypt Department of Tropical Medicine and Gastroenterology Faculty of MedicineAssiut UniversityAssiut 15655Egypt endemic Medicine Department Faculty of MedicineHelwan UniversityCairo 13544Egypt Internal Medicine 15 Mayo Smart HospitalMinistry of Health and PopulationCairo 13488Egypt Pediatrics Department Faculty of MedicineCairo UniversityCairo 11562Egypt Occupational and environmental Medicine Department Faculty of MedicineCairo UniversityCairo 11562Egypt Clinical Biochemistry Department Faculty of medicineCairo UniversityCairo 11562Egypt endemic Medicine Department Faculty of MedicineCairo UniversityCairo 11562Egypt Urology Department Cairo UniversityCairo 11562Egypt

BACKGROUND Various liver and gastrointestinal involvements occur in patients with coronavirus disease 2019(COVID-19)at variable *** studies report mild liver function disturbances correlated with COVID-19 severity,though liver failure is *** To study liver and gastrointestinal dysfunctions in Egyptian patients with COVID-19 and their relation to disease outcomes METHODS This multicentre cohort study was conducted on 547 Egyptian patients from April 15,2020 to July 29,*** polymerase chain reaction-confirmed COVID-19 cases were included from four quarantine hospitals affiliated to the Egyptian ministry of *** information,laboratory characteristics,treatments,fibrosis-4(FIB-4)index,COVID-19 severity,and outcomes were recorded and compared according to the degree of liver en.yme elevation and the presence of gastrointestinal ***-ups were conducted until discharge or *** analyses were performed to determine the independent factors affecting *** This study included 547 patients,of whom 53(9.68%)died during hospitalization and 1 was discharged upon his ***’mean age was 45.04±17.61 years,and 21.98%had severe or critical *** aminotransferase(ALT)and aspartate aminotransferase(AST)were available for 430 and 428 patients,*** total,26%and 32%of patients had elevated ALT and AST,*** liver injury with ALT or AST elevation exceeding 3-fold was recorded in 21(4.91%)and 16(3.73%)patients,*** gender,smoking,hypertension,chronic hepatitis C,and lung involvement were associated with elevated AST or *** was elevated in 50%of patients over ***-4 was significantly higher in patients admitted to the intensive care unit(ICU),those with more severe COVID-19,and *** independent variables affecting outcome were supplementary vitamin C intake(1 g daily capsules)[odds ratio(OR):0.05,95%confidence interval(CI

关键词： COVID-19 Egypt Liver injury Gastrointestinal symptoms Fibrosis-4 Liver en.ymes