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Optics and Ph.tonics Journal 2020年第8期10卷 197-209页

作者： laila h. gaabour Department of Ph.sics College of Science University of Jeddah Jeddah Saudi Arabia

In th. present work, magnetite (Fe3O4) nanoparticles h.ve been prepared by a simple ch.mical meth.d. Polymer nanocomposites based on th. blend between poly vinylamine fluoride (PVDF) and (meth.l meth.crylate) (PMMA) doped with.different concentrations of Fe3O4 nanoparticles h.ve been prepared. Th. structural, optical, and magnetization properties of th. nanocomposite samples were studied using suitable tech.iques. Th. X-ray study reflected th.t th. cubic spinal structure of pure Fe3O4 crystal. No small peaks or ripples were found in th. X-ray spectra, conforming to good dispersion of Fe3O4 with.n PVDF/PMMA matrices. Th. FT-IR analysis demonstrated th. miscibility between th. PVDF and PMMA blend with.th. interaction between th. polymer blend and Fe3O4. Th. values of th. band gap from UV-Vis study were decreased up to 4.21 eV, 3.01 eV for direct and indirect measurements, respectively. Th. magnetization was measured as a function of th. applied magnetic field in th. range of −2000 - 2000 Oersted. Th. curves of th. magnetization indicated a paramagnetic beh.vior of pure Fe3O4 nanoparticles and PVDF/PMMA-Fe3O4 nanocomposites. Th. values of saturation magnetization for pure Fe3O4 are nearly 75 emu/g, exh.biting a paramagnetic beh.vior, and it is decreased with.th. increase of Fe3O4 content.

关键词： PVDF/PMMA Blend Magnetite (Fe3O4) Nanoparticles XRD FT-IR UV-Vis Spectroscopy Magnetization Properties

Numerical Investigation of th. Plasma Formation in Distilled Water by Nd-YAG Laser Pulses of Different Duration

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Journal of Modern Ph.sics 2012年第10期3卷 1683-1691页

作者： laila h. gaabour Yosr Ezz El Din Gamal G. Abdellatif Department of Ph.sics Girl’s Faculty of Science King Abdul-Aziz University Jeddah KSA Ph.sics Department Faculty of Science Cairo University Giza Egypt

Water breakdown studies by Nd-YAG laser pulses of duration 100 fs, 30 ps and 6 ns at wavelength.1064 nm are pre- formed to investigate th. ph.sical mech.nisms wh.ch.couple th. laser energy into th. medium. Calculations are carried out applying a modified kinetic model of water breakdown previously developed by Kennedy (1995) to investigate th. correlation between th.esh.ld intensity of breakdown and laser pulse length. Th. modifications considered th. introduction of diffusion and recombination loss processes wh.ch.migh. take place under th. experimental conditions applied in th.se calculations. Th. validity of th. model is tested by comparing th. calculated th.esh.ld intensities and th. experimentally measured ones wh.re good agreement is sh.wn. Th. study of th. time evolution of th. electron density clarifies th. correlation between th. pulse length.and dominant ionization mech.nism. Th. analysis of th. spatial distribution of th. electron density along th. radial and axial distances of th. focal spot sh.wed th.t th. size of th. formed plasma increases with.th. increase of th. pulse length. On th. oth.r h.nd, studies of self-focusing effect illustrated th.t under th. investigated experimental conditions th. effect of th.s process h.s an effective contribution only at laser pulses of th. order of femtosecond scale wh.n th. laser beam is focused by a lens of a focal length.≥8.0 cm. Th.s result in turns assures th.t using femtosecond pulses in oph.h.lmic microsurgery could be a safe tool from th. retinal damage.

关键词： Laser Induced Breakdown Water Breakdown Electron Density Self Focusing Modeling of Plasma Formation Laser Medicine

Ch.nge of Spectroscopic Properties of PU/PVC Doped by Single Walled Carbon Nanotubes

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Optics and Ph.tonics Journal 2016年第12期6卷 305-314页

作者： L. h. gaabour Ph.sics Department Faculty of Science Alfaisaliah Campus King Abdulaziz University Jeddah KSA

Nanocomposite films based on polyureth.ne and polyvinyl ch.oride (PU/PVC) doped by low content (≤0.045 wt%) of single wall carbon nanotubes (SWCNTs) were prepared and ch.racterized. Th. structural, optical, th.rmal and mech.nical properties of th. prepared nanocomposites were ch.racterized by various tools. Th. IR band at 3437 cm-1 in SWCNTs vanish.ng for doped samples signified th.t SWCNTs were successfully covalently encapsulated with.PU/PVC. Th. X-ray peaks broaden with.reduced intensity wh.ch.refers to a reduction of th. crystallinity for th. blend after increase of SWCNTs attributed to ch.nging in th. crosslink density. UV/Vis analysis reveals th.t th. optical band gap values were decreased with.increased SWCNT attributed to th. formation of defects in polymeric matrix with.increase in th. degree of disorder in th. films. Th.se defects produce th. localized states in th. optical band gap. All results data sh.wed well dispersion of SWCNTs in polymer matrix at all weigh. percentages and an interaction between SWCNTs and th. blend occurred. Th. th.rmal analysis sh.wed th.t th. melting point (Tm) and degradation temperature (Td) of th. obtained films were increased gradually with.adding of SWCNTs. Furth.rmore, th. th.rmal stability was improved after adding SWCNTs into th. PU/PVC polymer blend.

关键词： Nanocomposites SWCNTs X-Ray TGA Mech.nical Properties

Energy Levels, Oscillator Strength., and Transition Probabilities of Ni XIX and Cu XX

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Optics and Ph.tonics Journal 2014年第3期4卷 54-89页

作者： Wessameldin S. Abdelaziz M. Atta Kh.dr Mai E. Ah.ed laila gaabour Th.rwat El-Sh.rbini Environmental Affairs Agency Cairo Egypt Laboratory of Lasers and New Materials Cairo University Giza Egypt National Institute of Laser Enh.nced Sciences Cairo University Giza Egypt Ph.sics Department Faculty of science King Abdul Aziz University Jeddah Saudi Arabia

Energy levels, oscillator strength., and transition probabilities, for th. 1s2 2s2 2p6, 2p53l (l = 0, 1, 2), 2p54l (l = 0, 1, 2, 3) states in Ni XIX and Cu XX are calculated using COWAN code. Th. Correlation and relativistic effects are considered. Th. calculations are compared with.oth.r results in th. literature. A good agreement is found. We also report on some unpublish.d energy values.

关键词： Energy Levels Oscillator Strength. Transition Probabilities

Impact of th. socioeconomic status on th. severity and outcome of community-acquired pneumonia among Egyptian ch.ldren: a coh.rt study

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Infectious Diseases of Poverty 2014年第1期3卷 128-134页

作者： Seh.m Fath. Abdel h.meed Azab laila M Sh.rief Safaa h.Saleh.Wafaa F Elsaeed Mona A Elsh.fie Sanaa M Abdelsalam Faculty of Medicine Zagazig UniversityEgypt18 Omar Bin Elkhattab StAl QawmiaZagazig CityAl Sharqia GovernorateEgypt

Background:Community-acquired pneumonia(CAP)is one of th. five leading causes of death.among ch.ldren in developing countries,accounting for approximately th.ee million death. per *** of th. modifiable risk factors of CAP may h.lp to reduce th. burden of th.s *** th.s study,th. impact of th. socioeconomic status(SES)on th. severity and outcome of CAP among Egyptian ch.ldren was ***:Th.s was a prospective longitudinal coh.rt study wh.ch.included 1,470 ch.ldren diagnosed with.CAP,aged two to 15 years(median age 5.4 years).Th. diagnosis of CAP was based on clinical and radiological findings.A structured questionnaire and th. patients’medical records were used for th. data *** subjects were divided into two groups:mild and severe *** and demograph.c variables were compared,and a multivariate logistic regression analysis was ***:Th. multivariate analysis sh.wed th.t a low maternal education level(OR:3.8;95%CI:2.12-6.70;P=.0001),unavailability of adequate medical care(OR:3.1;95%CI:1.99-4.88;P=.0001),a low family income(OR:2.2;95%CI:0.99-4.78;P=.047),and parents’smoking h.bits(OR:2.0;95%CI:1.15-3.55;P=.014)were significant independent predictive risk factors for severe CAP among Egyptian ***:Public h.alth.measures against th.se socio-demograph.c risk factors sh.uld be identified as priorities in order to h.lp reduce th. disease burden of death. from severe CAP among Egyptian ch.ldren.

关键词： Socioeconomic Community acquired pneumonia Ch.ldren

Noninvasive assessment of h.patic fibrosis in Egyptian patients with.ch.onic h.patitis C virus infection

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World Journal of Gastroenterology 2012年第23期18卷 2988-2994页

作者： Sh.wky Abdelh.mid Fouad Serag Esmat Dalia Omran laila Rash.d Moh.med h.Kobaisi Department of Internal Medicine Faculty of Medicine Cairo University Cairo 11562 Egypt Department of Tropical Medicine Faculty of Medicine Cairo University Cairo 11562 Egypt Department of Bioch.mistry Faculty of Medicine Cairo University Cairo 11562 Egypt Department of Path.logy National Institute of Nephrology Cairo 35789 Egypt

AIM: To evaluate th. accuracy of specific bioch.mical markers for th. assessment of h.patic fibrosis in patients with.ch.onic h.patitis C virus (h.V) infection. METh.DS: One h.ndred and fifty-four patients with.ch.onic h.V infection were included in th.s study; 124 patients were non-cirrh.tic, and 30 were cirrh.tic. Th. following measurements were obtained in all patients: serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin, total bilirubin, proth.ombin time and concentration, complete blood count, h.patitis B surface antigen (h.sAg), h.VAb, h.V-RNA by quantitative polymerase ch.in reaction, abdominal ultrasound and ultrasonic-guided liver biopsy. Th. following ratios, scores and indices were calculated and compared with.th. results of th. h.stopath.logical examination: AST/ALT ratio (AAR), age platelet index (API), AST to platelet ratio index (APRI), cirrh.sis discriminating score (CDS), Poh. score, G teborg University Cirrh.sis Index (GUCI). RESULTS: AAR, APRI, API and GUCI demonstrated good diagnostic accuracy of liver cirrh.sis (80.5%, 79.2%, 76.6% and 80.5%, respectively); P values were: h. studied parameters, AAR and GUCI gave th. h.gh.st diagnostic accuracy (80.5%) with.cutoff values of 1.2 and 1.5, respectively. APRI, API and GUCI were significantly correlated with.th. stage of fibrosis (P h. grade of activity (P h.le CDS only correlated significantly with.th. stage of fibrosis (P h.th. degree of activity (P > 0.05). In addition, we found significant correlations for th. AAR, APRI, API, GUCI and Poh. score between th. non-cirrh.tic (F0, F1, F2, F3) and cirrh.tic (F4) groups (P values: 0.05). CONCLUSION: Th. use of AAR, APRI, API, GUCI and Poh. score measurements may decrease th. need

关键词： Age platelet index Aspartate aminotrans-ferase platelet ratio index Aspartate aminotransferase-to-alanine aminotransferase ratio Cirrh.sis discrimi-nating score Fibrosis evaluation G^teborg UniversityCirrh.sis Index h.patitis C virus infection Liver fibro-sis Poh. score

Ch.racteristics and Outcomes of Coronavirus Disease 2019 (COVID-19) Infection among Ch.ldren Admitted in Al-Imam Abdulrah.an Al Faisal h.spital in Riyadh. Saudi Arabia

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Open Journal of Pediatrics 2021年第2期11卷 170-178页

作者： Abdullah.h. Alh.moud h.reth.A. Aldosaimani Abdullah.A. Alyah.a Ah.ad K. Almadani Nabil h. Madkh.li laila M. Alali Ibrah.m A. Alsah.bi Department of Laboratory Al-Imam Abdulrahman Al-Faisal Hospital First Health Cluster Ministry of Health Riyadh Saudi Arabia Department of Pediatrics Al-Imam Abdulrahman Al-Faisal Hospital First Health Cluster Ministry of Health Riyadh Saudi Arabia Department of h.alth.Management Al-Imam Abdulrahman Al-Faisal Hospital First Health Cluster Ministry of Health Riyadh Saudi Arabia Collage of Medicine Jazan Univerisity Jazan Saudi Arabia

Background: At th. beginning of th. COVID-19 pandemic, some reports demonstrated th.t ch.ldren are at lower risk of infection. Th.ugh. with.th. growing transmission of th. virus, it h.s been illustrated th.t it can in... 详细信息

Background: At the beginning of the COVID-19 pandemic, some reports demonstrated that children are at lower risk of infection. Though, with the growing transmission of the virus, it has been illustrated that it can infect children. Nevertheless, the features and outcomes of COVID-19 infection in children are still unclear. Objective: This study aims to describe the clinical characters and outcomes of children infected with COVID-19 and admitted to a hospital in Saudi Arabia. Design and Setting: This is a retrospective study that was carried out in Imam Abdulrahman Al Faisal Hospital in Riyadh, Saudi Arabia, by collecting data from patients’ records of children who were admitted to the hospital from March to July 2020. The collected data included information on the age and gender of the children, as well as their clinical course during hospitalization. Results: Thirty-three patients were included;39.4% of the children aged less than one year, 51.5% were males. Asthma occurred in 15.2% of patients. Asthma (p-value

ph.indicative Films Based on Ch.tosan–PVA/Sepiolite and Anth.cyanin from Red Cabbage: Application in Milk Packaging

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Journal of Bionic Engineering 2022年第3期19卷 837-851页

作者： Marya Raji laila El Foujji Moh.med El Meh.i Mekh.oum Mounir El Ach.by h.mid Essabir Rach.d Bouh.id Abou el kacem Qaiss Moroccan Foundation for Advanced Science Innovation and ResearchComposites and Nanocomposites CenterRabat Design CenterRue Mohamed El JazouliMadinat El IrfaneRabat10100Morocco Faculty of Science Laboratoire de Chimie Organique Et HétérocycliqueUniversity Mohammed V in RabatRabat10100Morocco Materials Science and Nano-Engineering Department Mohammed VI Polytechnic UniversityLot 660–Hay Moulay RachidBen Guerir43150Morocco Mech.nic Materialsand Composites(MMC)Laboratory of Energy EngineeringMaterials and SystemsNational School of Applied Sciences of AgadirIbn Zohr UniversityAgadir80000Morocco

Biobased smart packaging is been th. most interesting research.*** th.s study,ph.sensitive films based on anth.cyanin molecules from red cabbage and sepiolite mineral nano-clay as functional additives were *** films were fabricated by casting meth.d of blend polymer Ch.tosan/Poly(Vinyl Alcoh.l)at two fillers loading(5wt.%and 10wt.%).Th. structural,morph.logical,th.rmal,optical,h.groscopic,and mech.nical properties as well as th. ph.sensitivity of films were *** th.rmal properties confirm th.t th. amount of th. anth.cyanin in sepiolite was around 6.4%.Th. tensile strength.and th. young’s modulus of produced composites at 10wt.%sepiolite–anth.cyanin content was increased to 8.90 MPa and 163 MPa,*** maximum water absorption th.t th. films may absorb was 12.3%.ph.sensitivity analysis sh.wed th.t th. Smart films ch.nge th. color by ch.nging th. ph.level,from pink at ph.lower th.n 6 to yellow at ph.h.gh.r th.n ***,th. developed ph.sensitive films sh.w band gaps in visible ligh. th.t make th.m useful for monitoring milk spoilage.

关键词： Smart packaging Anth.cyanin Red cabbage ph.sensitive and milk spoilage

Insulin Resistance, Visceral Adiposity Index and TyG Index in Genotype-4 Ch.onic h.V Patients and Th.ir Relation to h.patic h.stopath.logy

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Open Journal of Gastroenterology 2016年第10期6卷 249-264页

作者： Eman A. Sabet Asmaa N. Moh.mmad laila M. Yousef Ah.ed R. h. Ah.ed Abeer Sh.neef Department of Internal Medicine Faculty of Medicine Sohag University Sohag Egypt Department of Tropical Medicine and Gastroenterology Faculty of Medicine Sohag University Sohag Egypt Department of Clinical Path.logy Faculty of Medicine Sohag University Sohag Egypt Department of Path.logy Faculty of Medicine Sohag University Sohag Egypt Department of Medical Microbiology and Immunology Faculty of Medicine Sohag University Sohag Egypt

Introduction: h.patitis C virus (h.V) genotype 4 is th. most prevalent in Egypt. Vis-ceral adiposity index (VAI) and (TyG) index are newly developed indices for assess-ment of metabolic syndrome (MS) and insulin resistance (IR). We aimed at comparing th.ir levels in h.V-patients with.h.alth. controls and validate th.ir use for prediction of h.patic h.stopath.logical ch.nges. Patient and Meth.ds: 78 ch.onic h.V-infected patients proven by PCR, viral genotyping and h.patic h.stopath.logy, and 67 h.alth. controls were enrolled. Presence of MS, h.meostasis Model Assessment for IR esti-mation (h.MA-IR), TyG index, and VAI were assessed. Results: h.MA-IR, TyG and frequency of MS were significantly h.gh.r in patients’ group (p p p = 0.002). Conclusion: h.V genotype 4 is significantly associated with.MS and increased values of h.MA IR and TyG index. TyG index and VAI are valuable simple indices th.t could predict th. h.stopath.logical ch.nges in Egyptian Ch. pa-tients.

关键词： h.V IR TyG VAI Steatosis Genotype 4

Th. COP9 SIGNALOSOME Is Required for Postembryonic Meristem Maintenance in Arabidopsis th.liana

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Molecular Plant 2015年第11期8卷 1623-1634页

作者： Anna Franciosini laila Moubayidin Kaiqi Du Nah.ll h. Matari Alessandra Boccaccini Simone Butera Paola Vittorioso Sabrina Sabatini Pablo D. Jenik Paolo Costantino Giovanna Serino Dipartimento di Biologia e Biotecnologie 'C. Darwin' Sapienza Universita di Roma Piazzale Aldo Moro 5 00185 Rome Italy Department of Biology Franklin & Marshall College Lancaster PA 17604-3003 USA Istituto Pasteur - Fondazione Cenci Bolognetti Dipartimento di Biologia e Biotecnologie 'C. Darwin' Sapienza Universita di Roma Piazzale Aldo Moro 500185 Rome Italy Institute of Agricultural Biology and Biotech.ology National Research Council of Italy (CNR) via Salaria km 29300 00015 Monterotondo Scalo Rome Italy

Cullin-RING E3 ligases （CRLs） regulate different aspects of plant development and are activated by modification of th.ir cullin subunit with.th. ubiquitin-like protein NEDD8 （NEural precursor cell expressed Developmentally Down-regulated 8）（neddylation） and deactivated by NEDD8 removal （deneddylation）. Th. CONSTITUTIVELY Ph.TOMORPh.GENIC9 （COP9） signalosome （CSN） acts as a molecular switch.of CRLs activity by reverting th.ir neddylation status, but its contribution to embryonic and early seedling development remains poorly ch.racterized. h.re, we analyzed th. ph.notypic defects of csn mutants and monitored th. cullin deneddylation/neddylation ratio during embryonic and early seedling development. We sh.w th.t wh.le csn mutants can complete embryogenesis （albeit at a slower pace th.n wildtype） and are able to germinate （albeit at a reduced rate）, th.y progressively lose meristem activity upon germination until th.y become unable to sustain growth. We also sh.w th.t th. majority of cullin proteins are progressively neddylated during th. late stages of seed maturation and become deneddylated upon seed germination. Th.s developmentally regulated sh.ft in th. cullin neddylation status is absent in csn mutants. We conclude th.t th. CSN and its cullin deneddylation activity are required to sustain postembryonic meristem function in Arabidopsis.

关键词： Arabidopsis th.liana cullin-Ring ubiquitin ligase COP9 signalosome embryo development seed maturation meristem