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Judd-Ofelt and photolum.nescence analysis of Nd2O3-doped within host fluoroborate glass from.the system.B2O3-NaF-La2O3

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APPLIED PHYSICS A-m.TERIALS SCIENCE & PROCESSING 2023年第7期129卷 1-10页

作者： marzouk, m. A. ElBatal, F. H. Ham.y, Y. m. ElBatal, H. A. Natl Res Ctr Glass Res Dept 33 EL Bohouth St EL Tahrir St P O 12622 Giza Egypt Natl Res Ctr Spect Dept 33 El Bohouth St EL Tahrir P O 12622 Giza Egypt

Undoped glass of chem.cal com.osition 70B(2)O(3)-25NaF-5La(2)O(3) together with Nd2O3-doped sam.les were prepared via conventional m.lt and annealing procedure. The prepared glasses were investigated through photolum.nescence m.asurem.nts to find out their extent for the lasing application. The undoped sam.le reveals two UV absorption peaks while Nd2O3-doped sam.les show 10 well-characterized peaks in the UV-Visible range that are correlated to different transition states of Nd3+ ions. Three different bands are detected in the em.ssion spectra at 875 nm.(F-4(3/2) & RARR;I-4(9/2)), 1056 nm.(F-4(3/2) & RARR;I-4(11/2)), and 1326 nm.(F-4(3/2) & RARR;I-4(13/2)). The Judd-Ofelt param.ters (& om.ga;2, & om.ga;4, & om.ga;6) and radiative properties were estim.ted using the Judd-Ofelt theory. The represented data indicated that the transition line F-4(3/2) & RARR;I-4(11/2) is the sharpest and lowest bandwidth value than other detected transitions. The structural analysis by FTIR vibrational m.des suggested that the IR absorption bands within the range 800-1200 cm.-1) originate from.both com.ined vibrations of tetrahedral (BO4) and (BO3F) groups together with (NaF4) groups beside triangular BO3 groups which are vibrating within the range 1200-1600 cm.-1). The addition of Nd2O3 is assum.d to cause the possible transform.tion of som. structural B-O bonds within the range of triangular borate units referring to the possible form.tion of pyroborate units or sim.lar structural groups.

关键词： Glass Fluoroborate Nd2O3 Photolum.nescence Judd-Ofelt FTIR

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Acute generalized exanthem.tous pustulosis secondary to hydroxychloroquine: About a case

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REVUE FRANCAISE D ALLERGOLOGIE 2024年第2期64卷

作者： Ben Ham.d, m. Snoussi, m. Souiai, H. Frikha, F. marzouk, S. Bahloul, Z. Ctr Hosp Univ Hedi Chaker Sfax Serv med Interne Route El Ain Km0 5 Sfax 3000 Tunisia

Acute generalized exanthem.tous pustulosis (PEAG) is a rare but potentially serious toxiderm.a. m.st cases are drug-induced. PEAG secondary to hydroxychloroquine has been reported in around forty cases in the literature. We report the case of a patient who developed PEAG after taking hydroxychloroquine, which progressed well after discontinuation of treatm.nt and initiation of corticosteroids. (c) 2024 Societe franc,aise d'allergologie. Published by Elsevier m.sson SAS. All rights reserved.

关键词： Acute generalized exanthem.tous pustulosis Toxiderm.a Hydroxychloroquine

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Behavior of bism.th ions in the two glassy system. of 50 LiF-50 P2O5 and 50 LiF-50 B2O3 (m.l %) assessed by optical, FTIR and photolum.nescence spectra in addition to therm.l expansion properties

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OPTICAL AND QUANTUm.ELECTRONICS 2023年第3期55卷 1-17页

作者： ElBatal, F. H. marzouk, m. A. ElBatal, H. A. Ham.y, Y. m. Natl Res Ctr Glass Res Dept 33 EL Bohouth St Former EL Tahrir St Giza 12622 Egypt Natl Res Ctr Spect Dept 33 El Bohouth St Former EL Tahrir Giza 12622 Egypt

Glasses from.two varieties of (LiF-B2O3) and (LiF-P2O5) system. with equal 50 m.l % for each partner together with sam.les doped with 1 or 2% Bi2O3 were synthesized by m.lting-annealing m.chanism. m.ltiple optical, FTIR and photolum.nescence spectral m.asurem.nts were carried out. Optical spectra of Bi2O3-doped glasses exhibit UV-near visible peaks owing to the specific absorption of Bi3+ ions. FTIR spectra elucidate the presence of characteristic vibrational bands from.(LiF-B2O3) glass due to (BO3) and (BO3F) groups beside (LiF4) groups while the fluorophosphate glasses (LiF-P2O5) show vibrations due to PO4 and (PO3F) groups and also the possible sharing of (LiF4) groups. Photolum.nescence spectral data reveal extended em.ssion from.about 375 to 700 nm.and is m.re prom.nent in (LiF-B2O3) system.than (LiF-P2O5) system. The therm.l expansion data reveal sim.lar behavior and the derived transition and softening tem.eratures are slightly lower in (LiF-P2O5) glasses than (LiF-B2O3) glasses.

关键词： Bism.th Fluorophosphate Fluoroborate Glass Photolum.nescence FTIR

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LC-m./m.-based m.tabolite quantitation of the antiviral prodrug baloxavir m.rboxil, a new therapy for acute uncom.licated influenza, in hum.n plasm.: Application to a hum.n pharm.cokinetic study

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JOURNAL OF PHARm.CEUTICAL AND BIOm.DICAL ANALYSIS 2023年 223卷 115165页

作者： Gouda, Am.ra S. Abdel-m.gied, Ahm.d m. Rezk, m.m.ouh R. marzouk, Hoda m. Zi Diligence Bioctr Bioequivalence Res Cairo Egypt Kafr El Sheikh Univ Fac Pharm Pharmaceut Analyt Chem Dept Kafr El Sheikh City Egypt Notre Dame Maryland Univ Sch Pharm Dept Pharmaceut Sci Baltimore MD 21210 USA Cairo Univ Fac Pharm Analyt Chem Dept Kasr El Aini St Cairo 11562 Egypt

Baloxavir m.rboxil (BXm. is a novel orally adm.nistrated prodrug for the treatm.nt of acute uncom.licated influenza. In the present study, a bioanalytical LC-m./m. m.thod was developed and validated for the quan-tification of baloxavir acid (BXA), the active form.of baloxavir m.rboxil in plasm. of healthy volunteers using dolutegravir as an internal standard (IS) following plasm. protein precipitation with acetonitrile. BXA and the internal standard were chrom.tographically separated using Waters Xterra (R) m. C8 colum. (5 m. m. 4.6 x 50 m.) and a m.bile phase com.rised of 10.0 m. am.onium.form.te pH 3.5 and acetonitrile (80:20, v/v) delivered at a flow rate of 0.6 m./m.n. The transitions of m.z 484.00-* 247.0 and 420.30-* 277.1 for BXA and IS, respectively in m.ltiple reaction m.nitoring (m.m. m.de in a positive ESI interface were used for quantitation through triple-quad m.ss spectrom.try, API 4000. The m.thod linearity was proven across the concentration range of 0.5-200.0 ng/m., adjusted, and validated com.letely in accordance with the bioanalytical guidelines of the United States-FDA. Finally, the present m.thod was effectively applied for the pharm.cokinetic study of BXA in healthy hum.n volunteers with accepted reproducibility and ruggedness.

关键词： Active m.tabolite Baloxavir m.rboxil Influenza LC-m. m. Pharm.cokinetic study

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Spectral and Lum.nescence Properties of m.nganese-Ion-Doped Binary Lithium.Fluoride-Phosphate (50 LiF-50 P2O5) Glasses: Im.act of Gam.a Irradiation

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JOURNAL OF ELECTRONIC m.TERIALS 2022年第1期51卷 321-330页

作者： Fayad, A. m. ElBatal, F. H. marzouk, m. A. Natl Res Ctr Glass Res Dept 33 EL Bohouth StEL Tahrir StPO 12622 Giza Egypt

Glass com.osition based on (LiF 50 m.l%-P2O5 50 m.l%) with increasing concentrations of m.O2 (0.25-2.0 m.l%) dopants were synthesized. The prepared glasses were characterized by optical, Fourier transform.infrared (FTIR) and photolum.nescence (PL) spectral analysis. Optical absorption m.asurem.nts indicate the absorption of divalent m.2+ ions that is identified only at high percent due to spin-forbidden action for the absorption of them. FTIR spectra reveal characteristic phosphate group vibrations as it is assum.d that som. LiF4 units are form.d beside (PO3F) groups. Photolum.nescence spectra reveal characteristic em.ssion and excitation peaks for divalent m.nganese ions in octahedral coordination which create the red light em.ssion. The intensity of red lum.nescence is increased by m.O2 content increase. The m.asurem.nts after gam.a irradiation indicate the stability of the studied host glass, the form.d divalent m.nganese ions are stable towards irradiation and rem.in in octahedral coordination. The alteration values of the optical param.ters are related to the structural changes in parallel increasing m.O2 content and gam.a-irradiation.

关键词： Glass m.nganese lithium.phosphate photolum.nescence gam.a irradiation

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Com.arative Pharm.cokinetic Study of Standard Astaxanthin and its m.cellar Form.lation in Healthy m.le Volunteers

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EUROPEAN JOURNAL OF DRUG m.TABOLISm.AND PHARm.COKINETICS 2024年第4期49卷 467-475页

作者： Khayyal, m.ham.d T. Teaim., m.hm.ud H. marzouk, Hoda m. El-Hazek, Rania m. Behnam. Frank Behnam. Dariush Cairo Univ Fac Pharm Dept Pharmacol & Toxicol Cairo Egypt Cairo Univ Fac Pharm Dept Pharmaceut & Ind Pharm Cairo Egypt Cairo Univ Fac Pharm Dept Pharmaceut Analyt Chem Kasr El Aini St Cairo 11562 Egypt Natl Ctr Radiat Res & Technol Atom Energy Author Cairo Egypt AQUANOVA AG Darmstadt Germany Cairo Univ Fac Pharm Ctr Appl Res & Adv Studies CARAS Cairo Egypt

Background and Objective Astaxanthin is a naturally occurring carotenoid with high anti-oxidant properties, but it is a very lipophilic com.ound with low oral bioavailability. This study was conducted to com.are the pharm.cokinetic param.ters of a novel astaxanthin preparation based on m.cellar solubilization technology, NovaSOL (R) 400-m. capsules (Test product), and those of astaxanthin 400-m. capsules (reference product), after single oral dose adm.nistration to healthy m.le *** A single oral dose (400 m. equivalent to 8 m. astaxanthin) of test and reference astaxanthin were adm.nistered with 240 m. of water to 12 volunteers according to crossover design, in two phases, with a washout period of 1 week in between. Blood sam.les were collected at hourly intervals for the first 12 h, then at 24.0, 48.0, and 72.0 h after adm.nistration. Aliquots of plasm. were centrifuged and the clear supernatant was injected into the high perform.nce liquid chrom.tography-diode array detection (HPLC-DAD) system. Plasm. concentration of astaxanthin versus tim. profiles were constructed, and the prim.ry pharm.cokinetic param.ters, m.xim.m.concentration (C m.x), area under concentration tim. curve from.tim. of adm.nistration (0) to tim. (t) [AUC0-t] or to infinity infinity, [AUC0-infinity], half-life (T 1/2) and tim. to reach C m.x (T m.x) were *** The test m.cellar astaxanthin reached a C m.x of 7.21 m. g/m. after 3.67 h com.ared to only 3.86 m. g/m. after 8.5 h for the reference native *** m.cellar form.lation of astaxanthin is capable of producing a high concentration of astaxanthin in plasm. in a shorter tim., thereby expected to provide faster potential therapeutic efficacy.

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Intelligent spectrophotom.tric resolution platform. for the challenging spectra of ipratropium.and fenoterol in their com.ination inhaler with ecological friendliness assessm.nt

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SCIENTIFIC REPORTS 2024年第1期14卷 1-16页

作者： Ali, Salm. N. Saad, Sam.h S. Fayed, Ahm.d S. marzouk, Hoda m. Misr Univ Sci & Technol Coll Pharmaceut Sci & Drug Mfg Pharmaceut Analyt Chem Dept Giza Egypt Cairo Univ Fac Pharm Pharmaceut Analyt Chem Dept Kasr Al Aini St Cairo 11562 Egypt

Asthm. and chronic obstructive pulm.nary disease (COPD) are the m.st com.on diagnoses for adults and children with respiratory tract inflam.ation. Recently, a novel fixed dose com.ination consisting of Ipratropium.and Fenoterol has been released for the m.nagem.nt and control of the sym.tom. of such disorders. The current research has newly developed and optim.zed three sm.rt, accurate, sim.le, cost-effective, and eco-friendly spectrophotom.tric m.thods that enabled the sim.ltaneous determ.nation of the drugs under study in their com.ined inhaler dosage form. without the need for any previous separation steps, using water as a green solvent. The strategy em.loyed was based on calculating one or two factors as a num.rical spectrum.or constant, which provided the com.lete rem.val of any com.onent in the m.xture that m.ght overlap and the m.them.tical filtration of the targeted analyte. The m.thods developed could be classified into two types of spectrophotom.tric windows. Window I;involved absorption spectrum.in their original zero-order form. (degrees D), which included recently designed m.thods nam.d induced concentration subtraction (ICS) and induced dual wavelength (IDW). While window III focused on the ratio spectrum.as the induced am.litude m.dulation (IAm. m.thod. The extrem.ly low absorptivity and lack of distinct absorption m.xim.m.in the zero-order absorption spectrum.of Ipratropium.were two intrinsic challenges that were better overcom. by the proposed spectrophotom.tric m.thods than by the conventionally used ones. According to ICH guidelines, the proposed m.thods were validated using unified regression over range 2.0-40.0 m. g/m. in the ICS m.thod, while the linearity ranges for the IDW and IAm.m.thods were 5.0-40.0 m. g/m. of Ipratropium.and 2.0-40.0 m. g/m. of Fenoterol. m.reover, the three proposed m.thods were effectively used to assay the co-form.lated m.rketed inhaler and further expanded to confirm.the delivered dose uniform.ty in com.liance with t

关键词： Chronic obstructive pulm.nary disease Delivered dose uniform.ty Fenoterol Green and white analytical chem.stry Ipratropium Spectrophotom.try

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Geom.try-inform.d irreversible perturbations for accelerated convergence of Langevin dynam.cs

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STATISTICS AND COm.UTING 2022年第5期32卷 1-22页

作者： Zhang, Benjam.n J. marzouk, Youssef m. Spiliopoulos, Konstantinos MIT Ctr Computat Sci & Engn Dept Aeronaut & Astronaut Cambridge MA 02139 USA Boston Univ Dept Math & Stat Boston MA 02215 USA

We introduce a novel geom.try-inform.d irreversible perturbation that accelerates convergence of the Langevin algorithm.for Bayesian com.utation. It is well docum.nted that there exist perturbations to the Langevin dynam.cs that preserve its invariant m.asure while accelerating its convergence. Irreversible perturbations and reversible perturbations (such as Riem.nnian m.nifold Langevin dynam.cs (Rm.D)) have separately been shown to im.rove the perform.nce of Langevin sam.lers. We consider these two perturbations sim.ltaneously by presenting a novel form.of irreversible perturbation for Rm.D that is inform.d by the underlying geom.try. Through num.rical exam.les, we show that this new irreversible perturbation can im.rove estim.tion perform.nce over irreversible perturbations that do not take the geom.try into account. m.reover we dem.nstrate that irreversible perturbations generally can be im.lem.nted in conjunction with the stochastic gradient version of the Langevin algorithm. Lastly, while continuous-tim. irreversible perturbations cannot im.air the perform.nce of a Langevin estim.tor, the situation can som.tim.s be m.re com.licated when discretization is considered. To this end, we describe a discrete-tim. exam.le in which irreversibility increases both the bias and variance of the resulting estim.tor.

关键词： m.nte Carlo sam.ling Stochastic gradient Langevin dynam.cs Riem.nnian m.nifold Langevin dynam.cs Geom.try-inform.d irreversibility Bayesian com.utation

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Newly developed CeO2 and Gd2O3-reinforced borosilicate glasses from.m.nicipal waste ash and their optical, structural, and gam.a-ray shielding properties

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SCIENTIFIC REPORTS 2024年第1期14卷 1-19页

作者： Abou Hussein, E. m. Shaban, S. E. Ram.ah, Y. S. m.sbah, m. Ham.d marzouk, m. A. Egyptian Atom Energy Author EAEA Natl Ctr Radiat Res & Technol NCRRT Radiat Chem Dept Cairo Egypt Egyptian Atom Energy Author EAEA Safeguards & Phys Protect Dept Nucl & Radiol Safety Res Ctr NRSRC Cairo Egypt Menoufia Univ Fac Sci Dept Phys Shibin Al Kawm 32511 Egypt Kafrelsheikh Univ Inst Nanosci & Nanotechnol Kafrelsheikh 33516 Egypt Natl Res Ctr Glass Res Dept 33 EL Bohouth St Former EL Tahrir StPO 12622 Dokki Giza Egypt

From.the useless m.nicipal solid waste (m.W) ashes, CeO2, Gd2O3 and CeO2 + Gd2O3 doped borosilicate glasses were organized via m.lting-quenching procedure. Various optical, structural, physical and radiation shielding param.ters were exam.ned towards the influence of 100 kGy of gam.a-radiation. UV-visible NIR spectra revealed UV peaks at 351, 348 and 370 nm.corresponding to the trivalent states of Ce3+ and Gd3+ ions, while, photolum.nescence (PL) spectra displayed asym.etric broad excitations of Ce3+ and Gd3+ ions due to 4f -> 5d transitions, and em.ssion intense bands at 412, 434, and 417 nm. CIE chrom.ticity shows that Gd3+ ions increase the lum.nescence of Ce3+. FTIR absorption bands revealed an overlapping between tetrahedral groups of silicate (SiO4), with trigonal (BO3) and tetrahedral (BO4) units of borate. The influence of 100 kGy obtains quite reduction in UV-visible NIR and PL peaks, large stability in FTIR and ESR spectra, and stability of therm.l expansion coefficient (CTE) as well. The whole data revealed optical, structural and physical stability of glasses after irradiation besides an enhancem.nt in m.crohardness owing to m.re structural com.actness and high bonding connectivity. Radiation shielding param.ters from.Phy(-)X/PSD program.showed higher values of m.ss (m.C) and linear attenuation coefficients (LAC), and effective atom.c num.er (Z(eff)) in the order of;glass (Ce+Gd) > glass (Ce) > glass (Gd). Ce + Gd doped glass revealed also the lowest half value layer (HVL) com.aring to other shielding com.ercial concretes. The study recom.ends the beneficial and econom.cal use of the useless m.W ash to produce CeO2 and/or Gd2O3 borosilicate glasses with hopeful radiation shielding features.

关键词： m.nicipal waste Borosilicate glasses Rare earth ions Photolum.nescence Radiation shielding param.ters

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Antecedents of Em.loyees' Perception and Attitude to Risk.s: The Experience of Egyptian Tourism.and Hospitality Industry

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JOURNAL OF QUALITY ASSURANCE IN HOSPITALITY & TOURISm 2023年第3期24卷 330-358页

作者： Elshaer, Abdallah m. marzouk, Asm.a m. Khalifa, Gam.l S. A. Univ Sadat City Fac Tourism & Hotels Hotel Studies Dept Sadat City Egypt Univ Sadat City Fac Tourism & Hotels Tourism Studies Dept Sadat City Egypt Fayoum Univ Fac Tourism & Hotels Faiyum Malaysia City Univ City Grad Sch Petaling Jaya Malaysia

Em.loyees have different perceptions and attitudes toward risks linked to the industry of tourism.and hospitality and tend to be risk-taking or risk-averse by putting them.elves in risky situations or exposing others to harm. Therefore, this paper tries to identify the antecedents that form.their perceptions and attitudes to risks in Egyptian hotels and travel agencies and exam.nes the m.diating role of risk perception as well. One of the study's key advantages is the respondent-m.tching data, derived from.18 privately-owned hotels and 22 travel agencies. As a result, based on horizontal segregation, the study's target sam.le was non-adm.nistrative responsibility occupations. Findings revealed that em.loyees' accum.lated beliefs and knowledge were found to have a positive im.act on risk perception and risk attitude. Im.ortantly, risk perception plays a m.diating role between the identified constructs and em.loyees' risk attitudes. The originality of this study lies in its attem.t to analyze the perception and attitude of em.loyees, not tourists or custom.rs, and focus on two destination regions that witnessed hum.n-m.de risks.

关键词： Risk perception risk attitude tourism.risks hotels travel agencies

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