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Structural and dielectric properties of prepared PbS and PbTe nanomaterials

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Journal of Semiconductors 2018年第12期39卷 52-59页

作者： A.A.hzab Azza A.Ward G.m.mahmoud eman m.El-Hanafy H.El-Zahed F.S.Terra Solid State Physics Department Physical Research DivisionNational Research CentreGizaEgypt microwave Physics and Dielectrics Department Physical Research DivisionNational Research CentreGizaEgypt University Girls College for Arts Scienceand EducationAin Shams UniversityHelioplesCairoEgypt

In this work, PbS and PbTe nanomaterials with various morphologies were synthesized by a hydrothermal method. The structural properties were investigated by using X-ray diffraction(XRD) and corresponding scanning electron microscopy together with their EDX analysis. Both the PbS and PbTe nanomaterials possess good polycrystalline structure. The crystallite size, determined from the XRD data, of PbS is 5 nm whereas the corresponding value of PbTe is 2.69 nm. SEm micrographs reveal that the prepared PbS nanomaterial has starshaped structures, micro-flowers, some cubes, and semi-dendrites, whereas PbTe has semi-flower structures. Additionally, the dielectric properties have been studied in a broad frequency range from 0.1 Hz up to 1 mHz at temperatures from 298-423 K. The real and imaginary parts of the complex dielectric constant ε' and ε" of PbTe are comparatively higher than those of PbS. moreover, the dielectric data were analyzed on the basis of the electric modulus.

关键词： dielectric properties PbS PbTe SEm EDX electric modulus

Exploring the anti-inflammatory bioactive metabolites of some marine algae through integration of metabolomics,network pharmacology and molecular docking analyses

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Food Bioscience 2022年第6期50卷 861-874页

作者： Dina S.Ghallab eman Shawky Doaa A.Ghareeb Shaymaa A.Abdulmalek Soad m.mohy El-Din mohamed m.mohyeldin Reham S.Ibrahim Department of Pharmacognosy Faculty of PharmacyAlexandria UniversityEgypt Center of Excellency for Preclinical Study (CE-PCS) Pharmaceutical and Fermentation Industries Development CentreCity of Scientific Research and Technological ApplicationsSRTA-CityNew Borg El-Arab CityAlexandriaEgypt Bio-screening and Preclinical Trial Lab Biochemistry DepartmentFaculty of ScienceAlexandria UniversityAlexandriaEgypt Biochemistry Department Faculty of ScienceAlexandria UniversityAlexandriaEgypt Botany and microbiology Department Faculty of ScienceAlexandria UniversityAlexandria21511Egypt

marine algae are well-acknowledged as a prime store of largely unexplored extraordinary chemical entities potentially ameliorating against inflammation however,the efficacy mechanism remains *** study offers an integrated strategy of several bioinformatics and computational tools as well as bio-guided fractionation,and multi-step experimental validations integrated with metabolomics to systematically provide a shortcut of potentially active anti-inflammatory biomarkers of ***,multi-level network model of“multi-components-multi-targets-multiple pathways”was ***,an in vitro anti-inflammatory testing was estimated via monitoring release of pro-inflammatory ***-guided fractionation of *** integrated with UPLC-mS analysis of the most promising enriched fractions in terms of anti-inflammatory efficacy were *** docking studies on the top enriched targets were ultimately ***-level network analysis illuminated that the intricate pharmacological mechanisms underlying inflammation mitigation was the knockout of the crucial targets of TLR2,AKT1 and PRKCA and further regulation of principal pathways as PI3K-Akt signaling pathway,arachidonic acid(AA)metabolism and Toll-like receptor signaling *** vitro testing,*** exhibited the greatest ***-mS analysis of Spirulina active fractions showed linolenic acid,hydroxy linolenic acid,eicosapentaenoic acid,catechin and carnosic acid were efficacy constituents for mitigating *** docking showed that eicosapentaenoic,hydroxy linolenic acid and carnosic acid displayed favorable molecular binding capacity to TLR2,AKT1 and *** rationally developed workflow offered the convincing evidence marine algae armed with an arsenal of weapons to regain the harmony disturbed in inflammatory disorders by multi-targeted synergistic functions.

关键词： Bioinformatics Seaweeds Network pharmacology molecular docking metabolomics

Seasonal Effect on Biomarkers of Exposure to Petroleum Hydrocarbons in the Coasts of North Western Suez Gulf,Egypt

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Journal of Environmental & Earth Sciences 2019年第1期1卷 38-48页

作者： Omayma E.Ahmed mustafa m.Emara Nazik A.Farid1 Enas A.El-Sabagh eman m.Kamal Egyptian Petroleum Research Institute Egypt Chemistry Department Faculty of Science(boys)Al-Azhar UniversityEgypt Faculty of Science(girls)Al-Azhar University CairoEgypt

Petroleum hydrocarbons of surface water were collected from eight loca-tions of from the coasts of north western Suez Gulf,*** extracted petroleum hydrocarbons were determined by gas chromatography-flame ionization detector and quantified by integrating the areas of both the resolved and unresolved *** results confirm that the con-centration is relatively higher than the recommended in the regulations of the Egyptian low of Environment of No.4/1994 of petroleum *** various *** dissolved petroleum hydrocarbons ranged from 5.639 to 74.8 and 1.868 to 65.698 mg/ml for summer and winter sea-sons,*** indicates that chronic oil pollution,in addition to hydrocarbon concentrations,the diagnostic indices used shows that the hydrocarbons in the area were comes from biogenic,petrogenic and anthropogenic ***-IR spectrometric analysis confirms die petro-genic nature of pollutants.

关键词： Egypt Oil hydrocarbon Physicochemical Diagnostic Gas chromatography Suez canal

Noninvasive Low-Intensity Focused Ultrasound mediates Tissue Protection following Ischemic Stroke

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Biomedical Engineering Frontiers 2022年第1期3卷 356-366页

作者： Alexandra m.Kaloss Lauren N.Arnold eman Soliman maya Langman Nathalie Groot Eli Vlaisavljevich michelle H.Theus Department of Biomedical Sciences and Pathobiology Virginia TechBlacksburgVA 24061USA Department of Biomedical Engineering and mechanics Virginia TechBlacksburg VA 24061USA Center for Engineered Health Virginia TechBlacksburg Virginia 24061USA

Objective and Impact *** study examined the efficacy and safety of pulsed,low-intensity focused ultrasound(LIFU)and determined its ability to provide neuroprotection in a murine permanent middle cerebral artery occlusion(pmCAO)*** ultrasound(FUS)has emerged as a new therapeutic strategy for the treatment of ischemic stroke;however,its nonthrombolytic properties remain ***,we examined how LIFU influenced neuroprotection and vascular changes following *** to the critical role of leptomeningeal anastomoses or pial collateral vessels,in cerebral blood flow restoration and tissue protection following ischemic stroke,we also investigated their growth and *** were exposed to transcranial LIFU(fundamental frequency:1.1 mHz,sonication duration:300 ms,interstimulus interval:3 s,pulse repetition frequency:1 kHz,duty cycle per pulse:50%,and peak negative pressure:-2.0 mPa)for 30 minutes following induction of pmCAO and then evaluated for infarct volume,blood-brain barrier(BBB)disruption,and pial collateral remodeling at 24 hrs *** found significant neuroprotection in mice exposed to LIFU compared to mock *** findings correlated with a reduced area of IgG deposition in the cerebral cortex,suggesting attenuation of BBB breakdown under LIFU *** also observed increased diameter of CD31-postive microvessels in the ischemic *** observed no significant difference in pial collateral vessel size between FUS and mock treatment at 24 hrs *** data suggests that therapeutic use of LIFU may induce protection through microvascular remodeling that is not related to its thrombolytic activity.

关键词： Focus repetition treatment

Launching a paradigm for first and redo-surgery in primary congenital glaucoma: institutional experience

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International Journal of Ophthalmology(English edition) 2019年第2期12卷 226-234页

作者： Tharwat H.mokbel eman m.El Hefney Sherein m.Hagras Amani E.Badawi manal A.Kasem Ahmed A.Al Nagdy Sherief E.El Khouly Walid m.Gaafar mansoura Ophthalmic Center Faculty of Medicine Mansoura University

AIm: To evaluate the outcome of the initial and the redo-surgeries for primary congenital glaucoma(PCG) correlated to its degree of severity. mETHODS: A retrospective study involved patients with PCG presented between 2010 and 2018. medical records were reviewed to assess the degree of the preoperative severity according to the intraocular pressure(IOP), corneal diameter and corneal edema. Success and failure rates were calculated for both first and redo-surgeries at 6 and 12 mo respectively then correlated to the severity of the cases. RESULTS: Complete records were retrieved for 272 eyes(153 patients) with PCG: 43 eyes were mild, 136 moderate and 93 severe. Combined trabeculotomy and trabeculectomy(CTT) had the highest success rate in moderate(96.4%) and severe cases(59.3%) while trabeculotomy had the highest success rate in mild cases(96.3%). medical records of 88 eyes(63 patients) with recurrent PCG were analyzed, most with severe presentation(59 eyes). Ahmed glaucoma valve(AGV) was used in 67(76%) eyes and augmented trabeculectomy in 21(24%) eyes. At 12 mo, there was no statistically significant difference between both surgeries in total success rate(P=0.256). For mild cases, success rate was 100% for both surgeries. Severe cases had higher success rates following AGV(87%) than augmented trabeculectomy(20%). Preoperative severity of the disease was an independent factor affecting the failure rate in secondary trabeculectomy but not in AGV. Patients younger than 24 mo had higher probabilities of failure following both redo-surgeries with hazard ratio =1.325 and 0.37 for augmented trabeculectomy and AGV respectively. CONCLUSION: Preoperative assessment of the severity of eyes with PCG helps in the selecting the optimal primary and secondary surgery. For first surgery, trabeculotomy is more effective in mild cases whereas; CTT and augmented subscleral trabeculectomy(SST) are appropriate for moderate and severe cases. AGV proved to be superior to augmented SST in

关键词： Ahmed glaucoma valve augmented trabeculectomy Egypt primary congenital glaucoma

The Reaction of Cyanoacetylhydrazine with Chloroacetone: Synthesis of 1,2,4-Triazine, 1,3,4-Oxadiazine and Their Fused Derivatives with Antitumor Activities

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Open Journal of medicinal Chemistry 2012年第1期2卷 1-9页

作者： Rafat m. mohareb eman m. Samir Department of Organic Chemistry Faculty of Pharmacy October University for Modern Sciences & Arts Giza Egypt National Organization for Drug Control & Research Cairo Egypt

The reaction of cyanoacetylhydrazine with chloroacetone gave the N-(1-chloropropan-2-ylidene)-2-cyanoacetohy- drazide. This compound reacted with either hydrazine hydrate or phenylhydrazine to give the corresponding 1,2,4-tri- azine derivatives. On the other hand, its reaction with either benzenediazonium chloride or benzaldehyde gave in each case the 1,3,4-oxadiazine derivatives. moreover, the reaction of the cyanoacetylhydrazine with 2-boromocyclohexa- none gave the corresponding hydrazine-hydrozon derivative. The antitumor evaluation of the newly synthesized prod- ucts against three cancer cell lines, namely breast adenocarcinoma (mCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268) was recorded. Some of the tested compounds showed activities which was higher than the reference doxorubicin.

关键词： 1 2 4-Triazine 3 4-Oxadiazine Pyrazole Antitumor

Investigating How Parental Perceptions of Cybersecurity Influence Children’s Safety in the Cyber World: A Case Study of Saudi Arabia

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Intelligent Information management 2023年第5期15卷 350-372页

作者： Tariq Saeed mian eman m. Alatawi Department of IS College of Computer Science and Engineering Taibah University Madinah Almunwarah Saudi Arabia

This paper explores the convergence of Saudi Arabia’s Vision 2030 with the increasing dependence on the Internet for educational purposes. It sheds light on the potential cybersecurity risks and how parental perception impacts children’s willingness to adapt cybersecurity features. By instilling the significance of cybersecurity awareness in early stages, society can provide children with the necessary skills to navigate the digital realm responsibly. As we progress, ongoing research and collaborative endeavors will be pivotal in formulating effective strategies to shield the digital generation from the potential pitfalls of the virtual realm. Regular Internet usage is essential for various purposes such as communication, education, and leisure. The cohorts of Generation Z and Alpha were born during a period of exponential Internet growth, leading them to heavily engage with the Internet. Consequently, they are equally vulnerable to cybersecurity threats just like adults. Addressing potential security risks for today’s youth becomes the responsibility of parents as the primary line of defense. This research focuses on raising awareness about the imperative of ensuring children’s safety in the online sphere, particularly by their parents. The study is conducted within the specific context of Saudi Arabia, aiming to examine how Saudi parents’ perception of cybersecurity influences their children’s cyber safety. The study identifies critical factors, including attitudes towards cybersecurity, awareness of cybersecurity, and prevailing social norms regarding cybersecurity. These factors contribute to the development of parents’ intention to prioritize cybersecurity, which consequently affects their children’s behaviors in the digital realm. Utilizing a quantitative approach based on a questionnaire, the study employs a Structural Equation modeling (SEm) framework to analyze the collected data. The study’s findings underscore that parents’ intent towards cybersecurity pl

关键词： E-Learning Cybersecurity Saudi Arabia Saudi Vision 2030 Cybersecurity Awareness Parenting in Cyber Era Adolescence

Embedded Coded Relay System for molecular Communications

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Computers, materials & Continua 2022年第8期72卷 2729-2748页

作者： eman S.Attia Ashraf A.m.Khalaf Fathi E.Abd El-Samie Saied m.Abd El-atty Konstantinos A.Lizos Osama Alfarraj Farid Shawki Imran Khan Ki-Il Kim Department of Electrical Engineering Faculty of EngineeringMinia UniversityMiniaEgypt Department of Electronics and Electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenoufiaEgypt Department of Informatics Faculty of Mathematics and Natural SciencesUniversity of Oslo(UiO)Norway Computer Science Department Community CollegeKing Saud UniversityRiyadh11437Saudi Arabia Department of Electrical Engineering University of Engineering&TechnologyPeshawar814Pakistan Department of Computer Science and Engineering Chungnam National UniversityDaejeon34134Korea

With the emergence of the COVID-19 pandemic,the World Health Organization(WHO)has urged scientists and industrialists to exploremodern information and communication technology(ICT)as a means to reduce or even eliminate *** World Health Organization recently reported that the virus may infect the organism through any organ in the living body,such as the respiratory,the immunity,the nervous,the digestive,or the cardiovascular *** the abovementioned goal,we envision an implanted nanosystem embedded in the intra living-body *** main function of the nanosystem is either to perform diagnosis and mitigation of infectious diseases or to implement a targeted drug delivery system(i.e.,delivery of the therapeutic drug to the diseased tissue or targeted cell).The communication among the nanomachines is accomplished via communication-based molecular *** control/interconnection of the nanosystem is accomplished through the utilization of Internet of bio-nano things(IoBNT).The proposed nanosystem is designed to employ a coded relay nanomachine disciplined by the decode and forward(DF)principle to ensure reliable drug delivery to the targeted ***,both the sensitivity of the drug dose and the phenomenon of drug molecules loss before delivery to the target cell site in long-distance due to the molecules diffusion process are taken into *** this paper,a coded relay Nm with conventional coding techniques such as RS and Turbo codes is selected to achieve minimum bit error rate(BER)performance and high signal-to-noise ratio(SNR),while the detection process is based on maximum likelihood(mL)probability and minimum error probability(mEP).The performance analysis of the proposed scheme is evaluated in terms of channel capacity and bit error rate by varying system parameters such as relay position,number of released molecules,relay and receiver *** results are validated through simulation and demonstrate that the proposed scheme can

关键词： molecular communication nanonetwork internet of bio-nano things coded relay scheme coding

Cardiac stem cells: Current knowledge and future prospects

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World Journal of Stem Cells 2022年第1期14卷 1-40页

作者： Radwa A mehanna marwa m Essawy mona A Barkat Ashraf K Awaad eman H Thabet Heba A Hamed Hagar Elkafrawy Nehal A Khalil Abeer Sallam marwa A Kholief Samar S Ibrahim Ghada m mourad medical Physiology Department/Center of Excellence for Research in Regenerative medicine and Applications Faculty of MedicineAlexandria UniversityAlexandria 21500Egypt Oral Pathology Department Faculty of Dentistry/Center of Excellence for Research in Regenerative Medicine and ApplicationsFaculty of MedicineAlexandria UniversityAlexandria 21500Egypt Human Anatomy and Embryology Department/Center of Excellence for Research in Regenerative medicine and Applications Faculty of MedicineAlexandria UniversityAlexandria 21500Egypt Center of Excellence for Research in Regenerative medicine and Applications Faculty of MedicineAlexandria UniversityAlexandria 21500Egypt Histology and Cell Biology Department/Center of Excellence for Research in Regenerative medicine and Applications Faculty of MedicineAlexandria UniversityAlexandria 21500Egypt medical Biochemistry Department/Center of Excellence for Research in Regenerative medicine and Applications Faculty of MedicineAlexandria UniversityAlexandria 21500Egypt Forensic medicine and Clinical toxicology Department/Center of Excellence for Research in Regenerative medicine and Applications Faculty of MedicineAlexandria UniversityAlexandria 21500Egypt

Regenerative medicine is the field concerned with the repair and restoration of the integrity of damaged human tissues as well as whole *** the inception of the field several decades ago,regenerative medicine therapies,namely stem cells,have received significant attention in preclinical studies and clinical *** from their known potential for differentiation into the various body cells,stem cells enhance the organ's intrinsic regenerative capacity by altering its environment,whether by exogenous injection or introducing their products that modulate endogenous stem cell function and fate for the sake of ***,research in cardiology has highlighted the evidence for the existence of cardiac stem and progenitor cells(CSCs/CPCs).The global burden of cardiovascular diseases’morbidity and mortality has demanded an in-depth understanding of the biology of CSCs/CPCs aiming at improving the outcome for an innovative therapeutic *** review will discuss the nature of each of the CSCs/CPCs,their environment,their interplay with other cells,and their *** addition,important issues are tackled concerning the potency of CSCs/CPCs in relation to their secretome for mediating the ability to influence other ***,the review will throw the light on the clinical trials and the preclinical studies using CSCs/CPCs and combined therapy for cardiac ***,the novel role of nanotechnology in cardiac regeneration will be explored.

关键词： Cardiac stem and progenitor cells Cardiac stem cells’secretome Cardiac stem cells’niche and metabolism Nanotechnology Clinical trials Combined therapy