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Exploitation of the antibacterial,antibiofilm and antioxidant activities of Salvadora Persica(Miswak)extract

Journal of Bioresources and Bioproducts 2023年第1期8卷 59-65页

作者： gamal M.El-Sherbiny Ahmed Mohamed Gazelly Mohammed H.Sharaf Saad A.Moghannemm Shehata M.E Mahmoud K.A.Ismail Ahmad S.El-Hawary Botany and Microbiology Department Faculty of Science(Boys)Al-Azhar UniversityCairo 11884Egypt

The Salvadora persica(***)*** stick,usually known as miswak,is still being em-ployed as an oral hygiene agent for plaque and gingivitis *** study aims to assess the antibacterial,antibiofilm,antioxidant,and phytochemical profile of *** *** ***-sica was purchased from a local market,grinded and extracted with petroleum *** disk dif-fusion,microdilution,and micro-plate assays were performed to evaluate the antibacterial and an-tibiofilm activities of the prepared extract at different concentrations against𝛽-lactam resistance Streptococcus *** radical scavenging 2,2-diphenyl-1-picrylhydrazyl(DPPH)and stable radical cationic chromophore,2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonate)(ABTS)methods were used to determine their antioxidant *** and spectrometric analyses were performed using gas chromatography-mass(GC-MS)*** minimum inhibitory concentration(MIC)of *** extract against𝛽-lactam resistance Streptococcus species ranged from 6.25 to 12.5 mg/*** maximum suppression of biofilm formation by *** extract was observed at MIC with a percentage of 68.66%,against Streptococcus *** *** ex-tract exhibited antioxidant activity with IC 50 of 20μg/mL and 35μg/mL from DPPH and ABTS,*** phytochemical characterization showed the presence of 22 compounds with ma-jor compounds;benzyl isothiocyanate(36.21%)and n-hexadecanoic acid(27.62%).The *** extract exhibited antibacterial activity against𝛽-lactam resistant Streptococcus species,showing a promising natural alternative that could be a treatment option.

关键词： β-lactam resistance Streptococcus species S.persica extract Antibacterial Antibiofilm Antioxidant GC-MS analysis

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Tagetones A and B, new cytotoxic monocyclic diterpenoids from flowers of Tagetes minuta

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Chinese Journal of Natural Medicines 2017年第7期15卷 546-549页

作者： Sabrin Ragab Mohamed Ibrahim gamal Abd Allah Mohamed Department of Pharmacognosy and Pharmaceutical Chemistry College of Pharmacy Taibah University Al-Madinah Al-Munawarah 30078 Saudi Arabia Department of Natural Products and Alternative Medicine Faculty of Pharmacy King Abdulaziz University Jeddah 21589 Saudi Arabia

Tagetones A(1) and B(2), two new monocyclic diterpenoids were isolated from the n-hexane fraction of fresh flowers of Tagetes minuta L.(Asteraceae). Their structures were established by multiple spectroscopic methods(IR, HR-ESI-MS, and 1D-, and 2D-NMR), in addition to comparison with literature data. Compound 1 showed cytotoxic activity towards MCF7 and A549 cancer cells with IC_(50) values being 4.68 and 4.24 μmol·L^(-1), respectively, compared to doxorubicin(IC_(50) 0.13 and 1.12 μmol·L^(-1), respectively). Compound 2 also exhibited significant activity against HCT116 cancer cells(IC_(50), 6.30 μmol·L^(-1)).

关键词： Tagetes minuta Asteraceae Monocyclic diterpenoids Tagetones Cytotoxic

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Topical Cyclosporine-A for Management of Epiphora in Eyes with Acquired Punctal Stenosis

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Open Journal of Ophthalmology 2022年第3期12卷 209-217页

作者： Mona Abdelhamid Nassief Ameera gamal Abdelhameed Sherein Mahmoud Hagras Faculty of Medicine Tanta University Tanta Egypt Faculty of Medicine Mansoura University Mansoura Egypt

Background: Cyclosporine A (CsA) is an inhibitor of calcineurin that prevents T-cell production of inflammatory cytokines and disrupts the immune-mediated inflammatory response that plays a crucial mechanism in punctal stenosis. Purpose: To evaluate the clinical outcomes and tolerances of CsA in treating epiphora in eyes with punctal stenosis. Study Design: Prospective study. Methods: The study included patients who presented with symptomatic epiphora associated with lower punctal stenosis during the period between July 2019 and December 2020. Patients were treated with topical 0.05% CsA on twice daily dose with topical preservative-free artificial tears Q.I. D. Patients were followed up monthly for at least 3 months by Munk epiphora grading, Fluorescein dye disappearance test (FDT) and evaluation of the patient satisfaction. Results: A total of 26 patients with 47 eyes were included in the study with a mean age of 55.1 ± 10.24 years. All the eyes had grade 0 lower punctal stenosis with grade 4 on Munk grading and grade 3 in FDT. There was a statistically significant difference in the Munk grading and FDT along the follow-up period compared to the baseline values (p Conclusion: CsA can control the inflammation of the conjunctival sac and restore the integrity of the ocular surface with subsequent symptomatic relief of the epiphora in eyes with punctal stenosis.

关键词： Cyclosporine A Epiphora Munk Grading Ocular Surface Punctal Stenosis

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linear and nonlinear fractional differential equation modified Riemann–Liouville derivatives exact solutions fractional auxiliary sub-equation expansion method Mittag–Leffler function method

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Communications in Theoretical Physics 2016年第2期65卷 127-135页

作者： Emad A-B.Abdel-Salam gamal F.Hassan Department of Mathematics Faculty of Science Assiut University New Valley Branch E1-Kharja 72511 Egypt

In this paper, the fractional auxiliary sub-equation expansion method is proposed to solve nonlinear fractional differential equations. To illustrate the effectiveness of the method, we discuss the space-time fractional KdV equation, the space-time fractional RLW equation, the space-time fractional Boussinesq equation, and the (3+1)-space-time fractional ZK equation. The solutions are expressed in terms of fractional hyperbolic and fractional trigonometric functions. These solutions are useful to understand the mechanisms of the complicated nonlinear physical phenomena and fractional differential equations. Among these solutions, some are found for the first time. The analytical solution of homogenous linear FDEs with constant coefficients are obtained by using the series and the Mittag–Leffler function methods. The obtained results recover the well-know solutions when α = 1.

关键词：非线性微分方程组分数阶微分方程 Liouville 辅助方程展开法生物改性 Boussinesq方程精确解

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Preliminary rib support requirements for solid coal ribs using a coal pillar rib rating(CPRR)

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International Journal of Mining Science and Technology 2021年第1期31卷 15-22页

作者： Khaled Mohamed Mark Van Dyke gamal Rashed Morgan MSears Robert Kimutis National Institute for Occupational Safety and Health Pittsburgh Mining Research DivisionPittsburghPA 15236USA

Researchers from the National Institute for Occupational Safety and Health(NIOSH)are developing a coal pillar rib rating(CPRR)technique to measure the integrity of coal *** CPRR characterizes the rib composition and evaluates its impact on the inherent stability of the coal *** CPRR utilizes four parameters:rib homogeneity,bedding condition,face cleat orientation with respect to entry direction,and rib *** these parameters are measurable in the field.A rib data collecting procedure and a simple sheet to calculate the CPRR were *** developed CPRR can be used as a rib quality mapping tool in underground coal mines and to determine the potential of local rib instabilities and support requirements associated with overburden *** calculations were conducted for 22 surveyed solid coal ribs,mainly composed of coal *** on this study,the rib performance was classified into four categories.A preliminary minimum primary rib support density(PRSD)line was obtained from these surveyed *** sample cases are presented that illustrate the data collection form and CPRR calculations.

关键词： Coal rib stability Rib support design Coal pillar rib rating Rib quality mapping CPRR Coal classification

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Change of the mode of failure by interface friction and width-to-height ratio of coal specimens

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第3期7卷 256-265页

作者： gamal Rashed Syd S.Peng Department of Mining Engineering West Virginia University

Bumps in coal mines have been recognized as a major hazard for many years. These sudden and violent failures around mine openings have compromised safety, ventilation and access to mine *** studies showed that the violence of coal specimen failure depends on both the interface friction and width-to-height（W/H） ratio of coal specimen. The mode of failure for a uniaxially loaded coal specimen or a coal pillar is a combination of both shear failure along the interface and compressive failure in the coal. The shear failure along the interface triggered the compressive failure in coal. The compressive failure of a coal specimen or a coal pillar can be controlled by changing its W/H ratio. As the W/H ratio increases, the ultimate strength increases. Hence, with a proper combination of interface friction and the W/H ratio of pillar or coal specimen, the mode of failure will change from sudden violent failure which is brittle failure to non-violent failure which is ductile failure. The main objective of this paper is to determine at what W/H ratio and interface friction the mode of failure changes from violent to non-violent. In this research, coal specimens of W/H ratio ranging from 1 to 10 were uniaxially tested under two interface frictions of 0.1 and 0.25, and the results are presented and discussed.

关键词： Bump Burst Coal strength Violent failure Width-to-height(W/H) ratio Interface friction Stressestrain curve

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A silent network’s resounding success:how mutations of core metabolic genes confer antibiotic resistance

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Signal Transduction and Targeted Therapy 2021年第9期6卷 2601-2602页

作者： gamal Wareth Heinrich Neubauer Lisa D.Sprague Friedrich-Loeffler-Institut Institute of Bacterial Infection and ZoonosesJenaGermany Department of Bacteriology Mycology and ImmunologyFaculty of Veterinary MedicineBenha UniversityToukhEgypt

A largely underrated factor in antibiotic resistance is the role of metabolic *** a recent paper published in Science,Lopatkin et al.1 used different in vitro evolution protocols and extensive sequencing data analyses to demonstrate that metabolic mutations develop in response to antibiotic treatment in clinically relevant bacteria(Fig.1).

关键词： resistance network silent

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锂硫电池碳基电催化剂的设计与合成

锂硫电池碳基电催化剂的设计与合成

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作者： gamal Hussein Ali Al-Shawesh 中国科学技术大学

学位级别：硕士

随着经济的发展,风能、太阳能和水力发电,等可持续能源越来越受到人们的关注。然而,由于太阳能和风能,等可再生能源的间歇性,各种可存储间歇性能源的电池、超级电容器,等电化学储能技术成为可再生能源利用过程的重中之重。在新一代储能... 详细信息

随着经济的发展,风能、太阳能和水力发电,等可持续能源越来越受到人们的关注。然而,由于太阳能和风能,等可再生能源的间歇性,各种可存储间歇性能源的电池、超级电容器,等电化学储能技术成为可再生能源利用过程的重中之重。在新一代储能技术中,锂硫电池（Li-S）因其成本低、环境友好且具有较高的理论能量密度(2600Wh kg)和理论比容量(1675 mAh g)而被认为是下一代储能系统中最有希望的候选者之一。然而,锂硫电池的商业化应用仍面临着一些严重问题。锂硫电池的性能取决于硫和其放电产物LiS/LiS之间的转化过程动力学,而上述转化过程缓慢的动力学过程严重影响其电化学性能。其次,锂硫电池中中间产物多硫化物（LiPS）的“穿梭效应”现象还需要根本性的突破以抑制其带来的容量快速衰减。因此,构建对LiPS具有高催化能力和强亲和力的载体材料仍然是必不可少的。该载体不仅能够物理地限制LiPS的扩散,而且还具备能够增强LiPS氧化还原过程的动力学的催化能力。为了克服这些问题,本论文通过探索不同的碳基质来固载和加速硫的转化。具体来说,通过对比具有不同氧缺陷的商业化碳纳米管:H-CNT、M-CNT和L-CNT,探索其中不同氧缺陷对Li-S电池多硫化物吸附和转化的影响。此外,通过引入铁单原子催化剂改进和优化碳基材料,设计了具备高导电性的多孔复合材料,研究了其电化学性能和其中的作用机制,具体研究如下:（1）我们探索了具有不同氧缺陷的碳纳米管:H-CNT、M-CNT和L-CNT,作为Li-S电池硫正极载体时,氧缺陷对于硫的催化转换反应作用机制及其电化学性能的影响。根据XPS结果得知,M-CNT具有最高的C-O含量,对LiPS转化具有最高的催化活性。M-CNT还具有导电多孔结构,可用于促进锂离子的传输和LiPS的有效固载,从而抑制穿梭效应。并且,M-CNT上的含氧缺陷（OD）还提供了增强LiPS转化的活性位点,其表面存在的氧官能团（C-O）对提高LiPS的催化能力起着至关重要的作用。因此,M-CNT/S复合材料在4 C下表现出高倍率性能（容量保持率为77%）和长循环稳定性(在1 C下循环600次后容量保持为 448.1 mAh g)。（2）成功制备了铁单原子（Fe-SAcs）和铁纳米颗粒（Fe-NPs）共嵌氮掺杂碳纳米管（Fe-NCNT）作为高性能Li-S电池的催化剂和载体。实验结果表明,均匀分散的Fe-As与Fe-NPs协同提供了有效的活性位点,增强了对LiPS的吸附和催化转化,进而优化了锂硫电池充放电过程中的氧化还原反应动力学。此外,氮掺杂的碳纳米管NCNT作为基体材料不仅可以提高正极的导电性,还可以缩短Li+的传输途径。因此,Fe-NCNT/S复合材料在1 C下循环500次后表现出1502.6 mAh g的显著初始比容量和597.8 mAh g的可逆比容量,每圈循环的容量衰减率低至0.069%。此外,载硫量为2.3 mg cm的Fe-NCNT/S电极在0.5 C循环200次后也显示出611.8 mAh g的高可逆比容量。

关键词：铁原子铁纳米粒子电催化剂氧官能团氮掺杂碳纳米管碳纳米管和锂硫电池

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也门移动支付业务的发展战略研究

也门移动支付业务的发展战略研究

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作者： Mohammed gamal Abdulrahman Al-Seddiq 中北大学

学位级别：硕士

移动支付业务作为更高层次的电子支付手段,已经成为国家信息化建设的重要标志。移动支付业务的发展改变了传统电信增值业务和金融业务的商业模式,对我国通信业和金融业政策管制提出了挑战,同时给设备制造商、移动运营商和银行等企业提... 详细信息

移动支付业务作为更高层次的电子支付手段,已经成为国家信息化建设的重要标志。移动支付业务的发展改变了传统电信增值业务和金融业务的商业模式,对我国通信业和金融业政策管制提出了挑战,同时给设备制造商、移动运营商和银行等企业提供了发展的新机遇,在这种前提下,如何推动移动支付业务的健康有序发展,成为值得深入研究的课题。论文在简要介绍移动支付业务的发展背景、基本原理和技术的基础上,分别对我国移动支付业务的总体发展环境、产业价值链和商业模式进行分析,然后探讨了我国移动支付业务的商业模式发展趋势和产业链各参与者的发展趋势,选取也门地区个人用户进行问卷调查,从个人用户对移动支付业务的认知度、消费习惯、业务选择倾向及消费方式、移动支付的使用情况和消费满意度等方面,对个人用户需求做了较为详细的分析;最后,根据个人用户需求和业务的发展趋势提出了移动业务发展的市场策略和产业价值链各参与者方面的发展策略,政策方面若干建议,希望对我国移动支付业务的整体发展提供有益的帮助。

关键词：移动支付发展战略移动支付业务也门

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Efficacy and Safety of Daclatasvir in Hepatitis C: An Overview

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Journal of Clinical and Translational Hepatology 2016年第4期4卷 336-344页

作者： Nesrine gamal Stefano Gitto Pietro Andreone Department of Medical and Surgical Sciences University of Bologna Bologna Italy

Hepatitis C virus (HCV) infection is a growing public health concern,with 184 million people infected *** the past decade,interferon has been the backbone of HCV treatment,even though it remains far from *** latest development of the new direct antivirals has drastically changed the treatment approach for chronic hepatitis C (CHC).Inhibitors of the HCV NS5A region have garnered remarkable interest among treating physicians,due to their high potency and favourable safety *** particular,treatment with daclatasvir (DCV) has yielded high rates of vriologic response in patients infected with genotype (Gt) 1 and Gt 3,when used in combination with other antivirals of a different class,such as *** few data are available for DCV treatment of the other Gts,the results in patients with Gt 2 and Gt 4 infection appear promising,as do those for unique patient ***5A-resistant viral variants can pre-exist or emerge after treatment failure for the HCV NS5A ***,DCV-resistant viral variants continue to be sensitive to interferon and other classes of antivirals such as NS3/4A and NS5B ***,we aimed to provide an overview of the current knowledge about DCV in the treatment of CHC.

关键词： Daclatasvir NS5A inhibitor Hepatitis C Direct antivirals New antiviral therapy

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