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Chinese Physics Letters 2017年第11期34卷 24-27页

作者： s.k.m.al-hayali s.selleri A.H.al-Janabi Institute of Laser for Postgraduate studies University of Baghdad Department of Information Engineering Parma University

We report on generation of a dual-wavelength, all-fiber, passively Q-switched ytterbium-doped fiber laser using aluminum oxide nanoparticle （al2O3-NP） thin film. A thin film of al2O3 was prepared by embedding al2O3-NPs into a polyvinyl alcohol （PVA） as a host polymer, and then inserted between two fiber ferrules to act as a saturable absorber （sA）. By incorporating the al2O3-PVA sA into the laser cavity, a stable dual-wavelength pulse output centered at 1050 and 1060.7nm is observed at threshold pump power of 80mW. As the pump power is gradually increased from 80 to 300mW, the repetition rate of the generated pulse increases from 16.23 to 59 kHz, while the pulse width decreases from 19 to 6μs. To the best of our knowledge, this is the first demonstration for this type of sA operating in the 1 μm region.

关键词： sA Dual-Wavelength Passively Q-switched Ytterbium-Doped Fiber Laser Based on aluminum Oxide Nanoparticle saturable Absorbers

Regression analysis of squeezing-induced hybrid nanofluid flow in Darcy-Forchheimer porous medium

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 193-208页

作者： k.mUHAmmAD m.sARFRAZ Department of Humanities and sciences School of Electrical Engineering and Computer Science National University of Sciences and Technology Department of mathematics Quaid-i-Azam University

This article presents a mathematical model addressing a scenario involving a hybrid nanofluid flow between two infinite parallel plates. One plate remains stationary, while the other moves downward at a squeezing velocity. The space between these plates contains a Darcy-Forchheimer porous medium. A mixture of water-based fluid with gold(Au) and silicon dioxide(si O2) nanoparticles is formulated. In contrast to the conventional Fourier's heat flux equation, this study employs the Cattaneo-Christov heat flux equation. A uniform magnetic field is applied perpendicular to the flow direction, invoking magnetohydrodynamic(mHD) effects. Further, the model accounts for Joule heating, which is the heat generated when an electric current passes through the fluid. The problem is solved via NDsolve in mATHEmATICA. Numerical and statistical analyses are conducted to provide insights into the behavior of the nanomaterials between the parallel plates with respect to the flow, energy transport, and skin *** findings of this study have potential applications in enhancing cooling systems and optimizing thermal management strategies. It is observed that the squeezing motion generates additional pressure gradients within the fluid, which enhances the flow rate but reduces the frictional drag. Consequently, the fluid is pushed more vigorously between the plates, increasing the flow velocity. As the fluid experiences higher flow rates due to the increased squeezing effect, it spends less time in the region between the plates. The thermal relaxation, however, abruptly changes the temperature, leading to a decrease in the temperature fluctuations.

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Predicting maximum Lifespan Limits at mean menopausal Age

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Journal of mathematical Research with Applications 2025年第1期 133-142页

作者： m.sUmATHI s.ANTONY CARLA Department of mathematics N.M.S.S.Vellaichamy Nadar College Research scholar (Part-time) Madurai Kamaraj University

The age at which a woman enters natural menopause has also been associated to death from any cause. menopause is a natural component of aging that happens between the ages of 45 and 55, with the average menopausal age being 51. Previous research has revealed the age at which women reach menopause, but there is no evidence to support the link between menopause and longevity. We made a study in assessing the limits of maximum lifespan at menopausal age in our previous article. In this paper, we aim to predict the maximum lifespan of women at mean menopausal age.

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Impact of Zika virus non-structural protein mutations on hippocampal damage

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Neural Regeneration Research 2025年第8期20卷 2307-2308页

作者： Larissa m.G.Cassiano Roney s.Coimbra Neurogenômica/Imunopatologia Instituto RenéRachouFiocruzBelo HorizonteBrazil Departamento de Bioquímica e Imunologia Instituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil

The Zika virus(ZIkV),a member of the Flaviviridae family,attracted worldwide attention for its connection to severe neurological effects,notably microcephaly in newborns,first reported during the 2015 epidemic in ***,its impact goes beyond fetal and neonatal abnormalities,also affecting the central nervous system(CNs)in both children and adults,leading to enduring cognitive and behavioral impairments.

关键词： damage fetal neonatal

Nanosecond pulse and dual-wavelength Q-switched 1.5 μm fiber laser using mAX phase Cr2TialC2 saturable absorber

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Optoelectronics Letters 2025年第1期21卷 7-12页

作者： Ahmed shakir al-HITI Hiba HAssAN Department of Electrical Engineering Faculty of Engineering University of Anbar Department of Laser and Optoelectronics Engineering University of Technology-Iraq

We demonstrated a new type of mAX phase material, chromium titanium aluminum carbide（Cr2TialC2） polymer film, to generate a passively Q-switched erbium-doped fiber laser（EDFL）. The film thickness was measured to be around 45 μm, which was fabricated using the embedding method with polyvinyl alcohol（PVA） polymer as hoster. The saturable absorber（sA） film demonstrates a dual-wavelength passively Q-switched EDFL which operates at 1 531 nm and 1 560.19 nm, respectively. The Q-switching pulse duration could be varied from 2.46 μs to 770 ns, while the repetition rate varied from 92.76 kHz to 106.6 kHz with an increasing input pumping range from 154 mW to 300 mW. The maximum output power and pulse energy of 15.05 mW and 141.18 nJ were obtained at the maximum input power of 300 mW, respectively.

关键词： saturable absorbers

Reduced Differential Transform method for solving Nonlinear Biomathematics models

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Computers, materials & Continua 2019年第9期61卷 979-994页

作者： k.A.Gepreel A.m.s.mahdy m.s.mohamed A.al-Amiri Department of mathematics Faculty of ScienceTaif UniversityTaif26571Saudi Arabia Department of mathematics Faculty of ScienceZagazig UniversityZagazig44519Egypt Department of mathematics Faculty of ScienceAl-Azher UniversityNasr CityCairo11884Egypt Department of mathematics Faculty of ScienceBisha UniversityBisha61922Saudi Arabia

In this paper,we study the approximate solutions for some of nonlinear Biomathematics models via the e-epidemic sI1I2R model characterizing the spread of viruses in a computer network and sIR childhood disease *** reduced differential transforms method(RDTm)is one of the interesting methods for finding the approximate solutions for nonlinear *** apply the RDTm to discuss the analytic approximate solutions to the sI1I2R model for the spread of virus HCV-subtype and sIR childhood disease *** discuss the numerical results at some special values of parameters in the approximate *** use the computer software package such as mathematical to find more iteration when calculating the approximate *** results and discussed quantitatively are presented to illustrate behavior of the obtained approximate solutions.

关键词： Reduced differential transforms method nonlinear biomathematics models sI1I2R model sIR model analytic approximate solutions qualitative analysis stability and equilibrium.

Prioritizing Indicators for Rapid Response in Global Health security:A Bayesian Network Approach

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International Journal of Disaster Risk science 2024年第4期15卷 536-551页

作者： Abroon Qazi mecit Can Emre simsekler m.k.s.al‑mhdawi school of Business Administration American University of SharjahSharjah 26666UAE Department of management science and Engineering Khalifa University of Science&TechnologyAbu Dhabi 127788UAE school of Computing Engineering&Digital TechnologiesTeesside UniversityMiddlesbrough TS13BXUK

This study explored a Bayesian belief networks(BBNs)approach,developing two distinct models for prioritizing the seven indicators related to the“rapid response to and mitigation of the spread of an epidemic”category within the context of both the specifc category and the Global Health security Index(GHs index).Utilizing data from the 2021 GHs index,the methodology involves rigorous preprocessing,the application of the augmented naive Bayes algorithm for structural learning,and k-fold *** fndings show unique perspectives in both BBN *** the mutual value of information analysis,“linking public health and security authorities”emerged as the key predictor for the“rapid response to and mitigation of the spread of an epidemic”category,while“emergency preparedness and response planning”assumed precedence for the GHs *** analysis highlighted the critical role of“emergency preparedness and response planning”and“linking public health and security authorities”in extreme performance states,with“access to communications infrastructure”and“trade and travel restrictions”exhibiting varied *** BBN models exhibit high predictive accuracy,achieving 83.3%and 82.3%accuracy for extreme states in“rapid response to and mitigation of the spread of an epidemic”and the GHs index,*** study contributes to the literature on GHs by modeling the dependencies among various indicators of the rapid response dimension of the GHs index and highlighting their relative importance based on the mutual value of information and sensitivity analyses.

关键词： Bayesian belief networks Global health security Indicators mitigation Policy implications Rapid response

Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs Víctor Cilleros-mañé Laia Just-Borràs marta Balanyà-segura aleksandra Polishchuk Laura Nadal marta Tomàs Carolina silvera-simón manel m.santafé maria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PkA and PkC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PkA/PkC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

A significant improvement in adsorption behavior of mesoporous TUD-1 silica through neodymium incorporation

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Journal of Rare Earths 2021年第4期39卷 469-476页

作者： Badria m.al-shehri sahar k.mohamed shaykha alzahly mohamed s.Hamdy Catalysis Research Group(CRG) Department of ChemistryCollage of ScienceKing Khalid UniversityP.O.Box 2009Abha61413Saudi Arabia Chemistry Department Collage of ScienceUmm Al-Qura UniversityMakkah21421Saudi Arabia Chemistry Department Faculty of ScienceHelwan UniversityAin HelwanCairo11795Egypt king Abdullah Institute for Nanotechnology King Saud UniversityRiyadh11451Saudi Arabia

Neodymium was incorporated into the three-dimensional mesoporous siliceous material *** order to understand the chemical and morphological structure of the prepared material,several characterization techniques were *** characterization results show the formation of highly distributed isolated Nd3+ions incorporated in the silica matrix in tetrahedrally coordinated structure,moreover no aggregation of separate phase(s)was/were *** prepared material was investigated as an adsorbent for methyl green(mG)dye in aqueous solution as a model cationic *** results show higher adsorption capacity for Nd-TUD-1 by almost 24 times higher than the neat parent TUD-1 material and more than 100 times higher than bulky Nd_(2)O_(3)under neutral *** adsorption results were fitted perfectly with pseudo-second-order ***,the adsorption isotherms were perfectly fitted with Freundlich isotherm model which indicates the formation of a multilayer of the dye molecules onto the Nd-TUD-1 surface as a physisorption with endothermic nature.

关键词： Adsorption Neodymium TUD-1 mesoporous silica Water treatment kinetics

Biogenic amino acid methionine-based corrosion inhibitors of mild steel in acidic media

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International Journal of minerals,metallurgy and materials 2019年第4期26卷 467-482页

作者： L.k.m.O.Goni m.A.Jafar mazumder s.A.ali m.k.Nazal H.A.al-muallem Chemistry Department King Fahd University of Petroleum and Minerals

N,N-Diallyl methionine ethyl ester hydrochloride 5 underwent alternating copolymerization with sO_2 via the Butler cyclopolymerization protocol in dimethyl sulfoxide(DmsO) to give water-soluble cycloterpolymer 6 with a ～1:1 molar ratio of sulfide and sulfoxide groups as a result of oxygen transfer from DmsO. Half of the sulfide groups in 6, upon oxidation with H_2O_2, afforded polymer sulfoxide 7 and polymer sulfone 8. The solution properties of these polymers were determined via a viscometric technique. The thermal stability of these polymers was determined by thermogravimetric analysis. The inhibition efficiency obtained from gravimetric mass loss, potentiodynamic polarization, and electrochemical impedance spectroscopy techniques agreed well with each other. The corrosion efficiencies increase with increasing concentration of the polymers. At a polymer concentration of 175 mm, the maximum inhibition efficiency of copolymer compounds 6–8 was determined to be 92%, 97%, and 95%, respectively. The synthesized polymer compounds acted as mixed-type inhibitors. Polymer compound 7 adsorbed onto the metal surface via chemisorption and physisorption and obeyed Langmuir, Temkin, and Freundlich adsorption isotherms. Analyses by X-ray photoelectron spectroscopy and scanning electron microscopy–energy-dispersive X-ray spectroscopy indicated that the adsorbed polymers formed a thin film on the metal surface and prevented further corrosive attack.

关键词： cyclopolymerization methionine methionine sulfoxide methionine sulfone diallylamine salt corrosion inhibition