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Photolum.nescence behavior of nano-structured sol-gel prepared zinc oxide activated with m.nganese and/or chrom.um.ions

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JOURNAL OF m.TERIALS SCIENCE-m.TERIALS IN ELECTRONICS 2021年第11期32卷 15491-15497页

作者： Ibrahim. S. Abo-Naf, S. m. marzouk, m. A. Natl Res Ctr Glass Res Dept 33 EL Bohouth StPO 12622 Giza Egypt

A series of zinc oxide co-doped m.2+ and/or Cr3+ were prepared via the citrate sol-gel m.thod. Full photolum.nescence (PL) analysis including em.ssion, excitation, CIE chrom.ticity, and lifetim. identifications of the prepared sam.les were carried out. The em.ssion spectra im.art a characteristic m.ltiline of em.ssions under UV excitation. The result of these em.ssions was the appearance of blue color as basic light em.ssion. The depth of blue light was detected at fixed UV excitation and it was m.inly dependent on the type and ratio of additions from.m.2+ and/or Cr3+. Single m.2+ or Cr3+ co-doped sam.les have the highest life tim. values than those of m.xed m.2+ together with Cr3+ co-doped sam.les. The results indicated that the preparation via the sol-gel technique can lead to a prom.sing photolum.nescent m.terial.

关键词： Optical and Electronic m.terials Characterization and Evaluation of m.terials

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The antibacterial effect of silver, zinc-oxide and com.ination of silver/zinc oxide nanoparticles coating of orthodontic brackets (an in vitro study)

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Bm. ORAL HEALTH 2022年第1期22卷 230-230页

作者： Zeidan, Noha K. Enany, Nagwa m. m.ham.d, Gehad Genidy marzouk, Eim.n S. Alexandria Univ Fac Dent Dept Orthodont Champollion StPOB 21521 Alexandria Egypt Cairo Univ Fac Sci Chem Depart Ment Giza 12613 Egypt Egypt Japan Univ Sci & Technol Basic & Appl Sci Inst Nanosci Dept Alexandria Egypt

Background Preventive m.asures are essential during the length of orthodontic treatm.nt to reduce the risk of decalcification and white spot lesions form.tion. With the evolution of procedures that enable coating of the orthodontic brackets using nanoparticles known for their good antibacterial activity, coating the brackets with nanoparticles of silver, zinc oxide and com.ination of silver and zinc oxide to evaluate their antibacterial effect in com.arison to a control group without coating was carried out in this study. m.thods Four groups of 12 brackets each were included in the study. The coating procedure was carried out using physical vapor deposition. The antibacterial activity was tested on Streptococcus m.tans and Lactobacillus Acidophilus using colony form.ng count. The antibacterial activity was evaluated im.ediately after coating and later after 3 m.nths. Results Brackets coated with com.ination of silver and zinc oxide nanoparticles had the highest ability on reduction of both Streptococcus m.tans and Lactobacillus Acidophilus count followed by silver nanoparticles and then zinc oxide nanoparticles. No significant difference was found between the first and second antibacterial tests. Conclusion The silver/zinc oxide nanoparticles coated brackets had the highest antibacterial effect in com.arison to silver nanoparticles and zinc oxide nanoparticles individually coated brackets on Streptococcus m.tans and Lactobacillus acidophilus, and all types of coatings showed enhanced antibacterial effect in com.arison to the uncoated bracket. Coating of orthodontic brackets could be further assessed in clinical application to prevent decalcification.

关键词： Orthodontics Brackets Coating Nanoparticles Silver Zinc oxide

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Rem.val of an em.rging pharm.ceutical pollutant, sulfasalazine, by adsorption onto pom.granate peels

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CHEm.CAL ENGINEERING COm.UNICATIONS 2022年第7期209卷 957-966页

作者： Bouallegue, m. C. Trifi, B. marzouk Trifi, I. Zahraa, O. Alatrache, A. Inst Natl Rech & Anal Physicochim Lab Mat Traitement & Anal LMTA Ariana Tunisia Univ Tunis El Manar Fac Sci Tunis Tunis Tunisia Univ Tunis El Manar Lab Dessalement & Traitement Eaux Fac Sci Tunis Tunis Tunisia Univ Lorraine Lab React & Genie Proc LRGP CNRS ENSICUMR 7274 Nancy France

The rem.val of an em.rging pharm.ceutical pollutant, sulfasalazine, which frequently detected in pharm.ceutical industry wastewater as well as in drinking water, has been investigated by adsorption on a biosorbent, prepared from.pom.granate peels in order to valorize food processing waste. After characterizing and determ.ning the surface functions, m.rphology and textural properties of the biosorbent pom.granate peels, the effect of pollutant concentration, pH and adsorbent am.unt on the adsorption activity were evaluated by varying one param.ter at a tim.. Results showed a quasi-total rem.val of sulfasalazine for a pH higher than 4.8, an initial pollutant concentration of 50 m. L-1 and an adsorbent m.ss of 0.5 g. The isotherm. kinetic and therm.dynam.c param.ters for sulfasalazine adsorption on the biosorbent have been estim.ted. Results revealed that the adsorption of sulfasalazine on pom.granate peels is a hom.genous m.nolayer, spontaneous and endotherm.c process following a pseudo-second-order kinetic.

关键词： Biosorbent em.rging pharm.ceutical pollutant isotherm. kinetic pom.granate peels therm.dynam.c

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A portable solid-state electrochem.cal sensor based on N-doped graphite as a transducer layer for determ.nation of a m.ltiple sclerosis m.naging m.dication in biological fluids

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JOURNAL OF SOLID STATE ELECTROCHEm.STRY 2022年第3期26卷 843-853页

作者： Ayish, Nada S. m.hm.ud, Am. m. Fayed, Ahm.d S. El-Zeany, Badr A. marzouk, Hoda m. Cairo Univ Analyt Chem Dept Fac Pharm Kasr El Aini St ET-11562 Cairo Egypt

Solid-state electrochem.cal sensors have shown trem.ndous prom.se for portable and reliable ion detection, thanks to im.lem.nting new functional m.terials as ion-to-electron transducer and innovative designs. Herein, a portable, disposable, and eco-friendly solid-state electrochem.cal sensor was established for the selective sensing of dalfam.ridine (FAm. in different m.trices. The fabricated sensor is based on utilizing N-doped graphite as an interm.diate transducer layer between calix[6]arene-doped PVC ion-sensing m.m.rane and a screen-printed electrode. This is the first tim. N-doped graphite m.terial is utilized in fabricating ion-selective electrode sensors. In-house synthesis of N-doped graphite was accom.lished by soft nitriding of graphite with urea. Then it was characterized using both X-ray photoelectron spectroscopy (XPS) and Fourier-transform.infrared spectroscopy (FT-IR). The electrochem.cal perform.nce of the developed sensor was assessed and com.ared to a transducer-free sensor. A significantly enhanced electrode perform.nce: detection lim.t of 5.98 x 10(-6) m.l L-1, rapid response tim. of 10 s, and reduced potential drift, was observed. The proposed sensor exhibits a Nernestian potentiom.tric slope of 59.19 m./decade over a linear response range of 8.0 x 10(-6) to 1.0 x 10(-2) m.l L-1. The proposed sensor has been efficaciously em.loyed for selective potentiom.tric determ.nation of FAm.in its pure form. pharm.ceutical form.lation, and in different biological fluids (plasm., urine, and hum.n m.lk) without any prior sam.le treatm.nt steps. Finally, analytical m.thod greenness was assessed using Eco-scale as well as Green Analytical Procedure Index (GAPI) approaches.

关键词： Solid-state ion selective electrodes Dalfam.ridine N-Doped graphite Soft nitriding Green analytical chem.stry

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m.thylation of receptor activator of nuclear factor kappa ligand (RANKL) gene in rheum.toid arthritis patients

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EGYPTIAN RHEUm.TOLOGIST 2023年第2期45卷 171-176页

作者： Ram.y, m.nal Gharbia, Ola m. Seleem. Am.l K. m.ham.d, Karim. marzouk, Rehab E. Mansoura Univ Fac Med Med Biochem & Mol Biol Dept Mansoura Dakahlia Egypt Helwan Univ Fac Med Med Biochem & Mol Biol Dept Cairo Egypt Mansoura Univ Fac Med Rheumatol & Rehabil Dept Mansoura Dakahlia Egypt

Background: Rheum.toid arthritis (RA) is an autoim.une inflam.atory disease characterized by synovi-tis, cartilage dam.ge and bone resorption. m.thylation of deoxyribonucleic acid plays a crucial role in repressing gene expression. Receptor activator of nuclear factor-kappa ligand (RANKL) controls bone hom.ostasis. Aim.of the work: To assess the serum.level of RANKL and its gene prom.ter m.thylation in RA patients and to determ.ne its association with clinical characteristics and disease activity. Patients and m.thods: The study included 40 RA patients and 40 control. The disease activity score (DAS28) was assessed. Frequency of RANKL gene prom.ter m.thylation was determ.ned by quantitative m.thylation speciflc PCR (Qm.P) and serum.RANKL level by enzym. linked im.unosorbant assay (ELISA). Results: Patients m.an age was 46.8 +/- 10.6 years, 36 fem.les and 4 m.les (F:m.9:1) with m.dian disease duration 4.5 years. Positive rheum.toid factor, anti-cyclic citrullinated peptide and C-reactive protein were present in 65 %, 75 % and 55 % of cases. m.thylation percentage of RANKL gene prom.ter was sig-niflcantly lower in patients (3.4 %) than in controls (3.7 %)(p = 0.035) while serum.level was signiflcantly increased in patients (9.1 ng/m.,5.3-11.8 ng/m.) than in controls (5.7 ng/m., 4.5-8 ng/m.)(p = 0.003). RANKL m.thylation frequency was inversely associated with serum.level (rs = -0.21,p = 0.06). There was no signiflcant correlation of RANKL serum.level and m.thylation with DAS28 (r = 0.03,p = 0.87 and r = 0.06,p = 0.73 respectively). RANKL serum.level (>9.5 ng/m.) and m.thylation percentage (<= 9%) signiflcantly discrim.nate RA cases from.control (sensitivity 47.5 %, speciflcity 91.9 %;p = 0.001 and sen-sitivity 100 %, speciflcity 40 %;p = 0.03 respectively). Conclusion: RA patients expressed elevated serum.RANKL with low m.thylation. (c) 2023 The Authors. Publishing services by ELSEVIER B.V. on behalf of The Egyptian Society of Rheum.tic

关键词： Rheum.toid arthritis m.thylation RANKL Gene prom.ter DAS28

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The role of CeO2 insertion and gam.a radiation in optoelectronic and ultrasonic transducer applications of PbO-B2O3 glasses

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JOURNAL OF NON-CRYSTALLINE SOLIDS 2024年 628卷

作者： Abou Hussein, E. m. Barakat, m.rham.A. Y. marzouk, m. A. Egyptian Atom Energy Author EAEA Natl Ctr Radiat Res & Technol NCRRT Radiat Chem Dept Cairo Egypt Natl Inst Stand Ultrason Metrol Dept Tersa St Haram 12211 Giza Egypt Natl Res Ctr Glass Res Dept 33 EL Bohouth St Former EL Tahrir StPO 12622 Giza Egypt

Novel B2O3-PbO glass system. doped CeO2 was developed and characterized. XRD and FTIR analyses were utilized to describe the glass structures. Chem.cal durability in 100 degrees C dis. H2O for 16 h and other glass's physical param.ters e.g. density, m.lar volum., specific volum. and oxygen packing density (OPD) were evaluated. Gam.a irradiation (80 kGy) causes an enhancem.nt in the glass properties like the aggregation of chem.cal durability by sim.lar to 50%, the density enhancem.nt and the com.actness. Ce3+/Ce4+ lum.nescent ions possess UV and blue em.ssions according to CIE chrom.ticity coordinates. Ultrasonic m.asurem.nts dem.nstrated a novel application. The prepared glasses is used as lenses in m.dical ultrasonic transducers. They gained a high-quality factor, a narrow bandwidth, and collim.ted waves for m.re accurate m.dical diagnosis and early disease detection. The transducer with lens 2 CeO2 m.l% had the highest quality factor (6.9 %), the narrowest bandwidth (0.7 m.z), and revealed the highest optoelectronic efficiency.

关键词： Lead borate glass Chem.cal durability m.dical ultrasonic transducer Photolum.nescence Gam.a radiation

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Im.acts of BaO additives on the m.chanical, optical and radiation shielding properties of BaO-K2O- CoO-Al2O3-B2O3 glasses

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OPTICAL m.TERIALS 2023年第1期143卷

作者： Sam.r, A. Hassan, m.ukhtar A. Ahm.d, F. Sadeq, m. S. marzouk, S. Y. m.rshidy, H. Y. Benha Univ Fac Engn Shoubra Basic Sci Dept Banha 11629 Egypt Al Azhar Univ Fac Sci Phys Dept Cairo 11884 Egypt Al Azhar Univ Fac Sci Phys Dept Girls Branch Cairo 11754 Egypt Sinai Univ Fac Engn Basic Sci Dept Arish Egypt Middle East Univ MEU Res Unit Amman Jordan Arab Acad Sci & Technol Cairo 2033 Egypt Midocean Univ Res & Studies Ctr Moroni 6063 Comoros

This article reports the influence of barium.oxide (BaO) on m.chanical and radiation protection characteristics of BaO-K2O- CoO-Al2O3-B2O3 glass. The obtained results confirm.d the enhanced the elastic m.duli, confirm.ng a high cross-linked density, high im.act resistance, and toughness of the network, with the good m.chanical stability of sam.les with further additives of BaO. In detail, with increasing BaO contents, it is observed that the shear m.dulus increased from.33.8 GPa reaching 37.7 GPa (increased by about 11.5%), while the longitudinal m.dulus enhanced from.100.5 GPa up to 117.4 GPa (enhanced by ? 16.8%), besides Young's m.dulus augm.nted from.84.4 GPa to 95.3 GPa (augm.nted by ? 13%), and bulk m.dulus is increased from.55.4 GPa reaching 67.2 GPa (increased by ? 21.3%). These enhancem.nts in the elastic m.duli are attributed to the increased tetrahedral units (BO4 and AlO4 units) inside the glass m.trix with increasing BaO additives. On the other hand, with increasing BaO, optical band gaps increase from.3.07 eV to 3.58 eV, and ligand field strength values decrease from.3494 cm.- 1) to 3273 cm.- 1). Furtherm.re, the addition of BaO reduces the linear and nonlinear refractive indices. m.reover, the obtained radiation shielding param.ters were studied and com.ared to those of well-known shielding m.terials. The com.arison confirm.d that the glass specim.n with the highest barium.oxide content has better radiation shielding ability than others and is suitable for radiation shielding applications.

关键词： Co(2+)and Ba2+ ions m.chanical properties Shielding purposes

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Hybrid leader based optim.zation with deep learning driven weed detection on internet of things enabled sm.rt agriculture environm.nt

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COm.UTERS & ELECTRICAL ENGINEERING 2022年第PartA期104卷

作者： Alrowais, Fadwa Asiri, m.shael m. Alabdan, Rana marzouk, Radwa Hilal, Anwer m.stafa Alkhayyat, Ahm.d Gupta, Deepak Princess Nourah bint Abdulrahman Univ Coll Comp & Informat Sci Dept Comp Sci POB 84428 Riyadh 11671 Saudi Arabia King Khalid Univ Coll Sci & Art Mahayil Dept Comp Sci Abha Saudi Arabia Majmaah Univ Coll Comp & Informat Sci Dept Informat Syst Al Majmaah 11952 Saudi Arabia Princess Nourah bint Abdulrahman Univ Coll Comp & Informat Sci Dept Informat Syst POB 84428 Riyadh 11671 Saudi Arabia Prince Sattam bin Abdulaziz Univ Preparatory Year Deanship Dept Comp & Self Dev Alkharj Saudi Arabia Islamic Univ Coll Tech Engn Najaf Iraq Maharaja Agrasen Inst Technol Dept Comp Sci & Engn Delhi India Chandigarh Univ UCRD Mohali Punjab India

Recent technological advancem.nts of Cloud Com.uting (CC), Internet of Things (IoT), Artificial Intelligence (AI), com.uter vision, etc. enable the transform.tion of traditional agricultural practices into sm.rt agricultural practices. In this background, the current article introduces a novel Hybrid Leader-based Optim.zation with DL-driven Weed Detection in IoT-enabled Sm.rt Agriculture (HLBODL-WDSA) m.del. The prim. aim.of the proposed HLBODL-WDSA m.del is to collect the im.ges using IoT devices and recognize the weeds autom.tically. Initially, the HLBODL-WDSA m.del enables the IoT devices to capture the farm.im.ges and transm.ts the im.ges to the cloud server for exam.nation. Next, the HLBODL-WDSA m.del applies YOLO-v5-based weed detection process in which HLBO algorithm.is exploited as a hyperparam.ter optim.zer. Finally, the Kernel Extrem. Learning m.chine (KELm. m.del is applied for effective classification of the weeds. The proposed HLBODL-WDSA m.del was experim.ntally validated and the outcom.s established the better perform.nce of the proposed HLBODL-WDSA m.del over recent approaches.

关键词： Internet of Things Sm.rt farm.ng Deep learning Agriculture Param.ter optim.zation Com.uter vision Object detection m.taheuristics

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Secure fram.work for IoT technology based on RSA and DNA cryptography

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EGYPTIAN JOURNAL OF m.DICAL HUm.N GENETICS 2022年第1期23卷 1-7页

作者： Elam.r, m.na m. m.brouk, m.y S. marzouk, Sam.r Y. Helwan Univ Biomed Engn Dept Cairo Egypt Misr Univ Sci & Technol Biomed Engn Dept Cairo Egypt Arab Acad Sci & Technol AASTMT Fac Engn Basic & Appl Sci Dept Cairo Egypt

Background The Internet of things (IoT) is the network of different objects or "things" containing sensors, software, and other technologies used to exchange data between devices and system. over the cloud. Such system. and networks should be provided with a proper cryptographic m.thodology to block unauthorized data transm.ssion access. This issue is considered an essential challenge of resources that are shared on the data com.unication network, that is its security. So, in this study, a cryptosystem.is proposed to m.intain the security level of such system. with a new idea depending on DNA cryptography and DNA m.xing. Results In this study, the proposed cryptosystem.is based on the RSA algorithm.and DNA cryptography concepts with a novel idea for m.xing DNA strands obtained from.encoding m.dical im.ge and report to enhance the security level through the IoT networks. This system.achieved a proper result in reconstructing im.ges with high quality. The sim.larity between the original data and the restored one reached 92% through 18 s. Conclusions Such a proposed cryptosystem.provided the feasibility of data security in network security, especially for E-health care through IoT system.to help m.dical team.ork in handling m.dical data between hospitals safely. The result showed that RSA is a fast, efficient algorithm.that can be utilized safely in cryptography schem.s.

关键词： RSA algorithm Im.ge encryption DNA cryptography IoT security

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Innovative pH-dependent approach for electrochem.cal determ.nation of a triple eradication therapy targeting H. Pylori infection in pharm.ceutical form.lation and hum.n plasm. sam.le: m.dified electrode with Prussian blue analogue decorated m.lti-walled carbon nanotubes (PbA@m.CNT)

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m.CROCHEm.CAL JOURNAL 2022年 181卷

作者： Darweish, Em.n Abdel-Raoof, Ahm.d m. marzouk, Hoda m. Ashm.wy, Ashraf m. Fayez, Yasm.n m. Eissa, m.ya S. Egyptian Russian Univ Fac Pharm Pharmaceut Chem Dept Cairo 11829 Egypt Al Azhar Univ Fac Pharm Boys Pharmaceut Analyt Chem Dept Cairo 11751 Egypt Cairo Univ Fac Pharm Analyt Chem Dept Kasr Al Aini St Cairo 11562 Egypt Al Azhar Univ Fac Sci Chem Dept Cairo 11884 Egypt

In the present study, a sensitive and cost-effective voltam.etric m.thod was developed, optim.zed and applied for assessm.nt of a new com.ination of a triple therapy treatm.nt that contain tinidazole (TZ), clarithrom.cin (CLR) and lansoprazole (LAN) depending on different pH effect. The study was developed using electrode of carbon paste im.roved by Prussian blue analogue nanoparticles in addition to m.lti-walled carbon nanotubes (PbA-NPs/m.CNT/CPE). The characterization and m.rphology of the nanoparticles com.osite was studied for the adopted electrode by X-ray diffraction (XRD) patterns, scanning electron m.croscope (SEm. and Transm.ssion Electron m.croscope (TEm.. Effect of different electrodes and content of PbA-NPs on the voltam.etric perfor-m.nce of the three drugs were assessed. Differential pulse voltam.etry (DPV) was estim.ted and linear corre-lations were then obtained in the range of 0.01-0.9, 1.0-10.0 and 0.5-12.0 m. g/m. for LAN, CLR and TZ, respectively. The optim.zed m.thod has been validated as per the ICH guidelines and found to be appropriate for the routine quality control of the studied drugs in their pharm.ceutical form.lation in addition to spiked hum.n plasm.. Consequently, the proposed m.thod definitely provides an efficient, beneficial, reliable and cost-effective tool for estim.tion of the cited active pharm.ceutical ingredients.

关键词： Triple therapy com.ination pH-dependent approach Differential pulse voltam.etry Prussian blue analogue m.ltiwall carbon nanotube

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