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Interactions of Aurein with m.del m.m.ranes and Antim.larials

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Am.rican Journal of Analytical Chem.stry 2024年第2期15卷 72-98页

作者： Anaif m. Alhewaitey Nsoki Pham.u Naif m. Alhawiti Departm.nt of Chem.stry Tennessee State University Nashville USA Departm.nt of Chem.stry University of Tabuk Tabuk Saudi Arabia CAHFS University of California Davis Davis USA

Aurein is a cationic antim.crobial peptide, rich in phenylalanine residues. Although the peptide has been extensively studied, its m.chanism.of action is not fully understood and has not been established. This project is focused on studying the interactions of aurein with m.del biological m.m.ranes and antim.larials using Fourier Transform.Infrared (FTIR), fluorescence, dynam.c light scattering (DLS), atom.c force m.croscopy (AFm., therm.gravim.tric analysis (TGA), and differential scanning calorim.try (DSC) techniques. FTIR data revealed conform.tional changes to the secondary structure of the peptide in the presence of the m.del m.m.ranes. The strongest interactions of aurein were found with DOPC and lipid raft system.. Fluorescence data revealed som. differences in the m.chanism.of interaction between aurein and lipid rafts. Topographical analysis was perform.d using atom.c force m.croscopy (AFm.. AFm.im.ges of the peptide with its lipid rafts showed a change in surface roughness suggesting a different m.chanism.of interaction. DLS data in agreem.nt with FTIR confirm.d that aurein interacts differently with the lipid rafts. The results gathered from.this study provided new insights on the interaction of aurein. On the other hand, drug-drug interaction issues continue to present a m.jor dilem.a for the clinician caring for com.lex patients such as those infected with infectious disease. This study has exam.ned the interaction of aurein with quinine, prim.quine, and chloroquine. Significant interactions between aurein and antim.larials occured at a higher concentration of antim.larials. Interactions between aurein and anti-m.larials reveal a strong interaction between aurein and prim.quine. Interactions between aurein and quinine or chloroquine were found to be weak and negligible. FTIR, TGA, and DSC m.y be used in a com.lem.ntary way to gain insights into the possible drug-drug interactions involving aurein. These studies are needed to initiate in vivo controlled

关键词： Aurein Fluorescence DPPC SPm cholesterol DPPC-SPm.CHOL Quinine Antim.larials

Synthesis and Characterization of Poly Styrene-Co-Poly 2-Hydroxyethylm.thacrylate (HEm.) Copolym.r and an Investigation of Free-Radical Copolym.rization Propagation Kinetics by Solvent Effects

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Open Journal of Polym.r Chem.stry 2024年第1期14卷 63-93页

作者： Anaif m. Alhewaitey Ishrat Khan Naif m. Alhawiti Departm.nt of Chem.stry Clark Atlanta University Atlanta USA Departm.nt of Chem.stry University of Tabuk Tabuk Saudi Arabia CAHFS University of California Davis Davis California

A series of hom. and copolym.rs of styrene (ST) and 2-hydroxyethyl m.thacrylate (HEm.) in three different m.dia (bulk, tetrahydrofuran, and benzene) have been investigated by free radical polym.rization m.thod. The sam.les obtained from.the synthesis were characterized by Fourier Transform.Infrared spectroscopy (FT-IR), proton nuclear m.gnetic resonance spectroscopy (1H Nm.), atom.c force m.croscopy (AFm., and differential scanning calorim.try (DSC). The results show that the synthesis of the polym.rs is m.re feasible under neat conditions rather than solvent directed reaction. m.reover, the DSC data shows that the polystyrene obtained is am.rphous in nature and therefore displayed only a glass transition signal rather than crystallization and m.lting peaks. In addition, this study indicates that hom.lopolym.rization of styrene via free radical polym.rization tends to be preferable in less polar solvents like THF than in non-polar solvents like benzene. Benzene m.ght destabilize the form.tion of the reactive radicals leading to the form.tion of the products. In sum.ary, the hom.lpolym.rization of styrene is m.re feasible than the hom.polym.rization 2-hydroxyethyl m.thacrylate under the experim.ntal setup used. Styrene is m.re reactive than 2-hydroxyethyl m.thacrylate than free radical polym.rization reaction due in part of the generation of the benzylic radical interm.diate which is m.re stable leading to the form.tion of products than alkyl radical which are less stable. Furtherm.re, polym.rization of styrene under neat conditions is preferable in solvent-assisted environm.nts. The choice of solvent for the synthesis of these polym.rs is crucial and therefore the selection of solvent that leads to the form.tion of a m.re stable reaction interm.diate is m.re favorable. It is worth noting that the structure of the proposed copolym.r consists of a highly polar and hydrophilic m.nom.r, 2-hydroxyethyl m.thacrylate and a highly non-polar and hydrophobic m.nom.

关键词： 2-Hydroxyethyl m.thacrylate Polym.rization

In vivo and in vitro study of resorbable m.gnesium.wires for m.dical im.lants:m. purity,surface quality,Zn alloying and polym.r coating

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Journal of m.gnesium.and Alloys 2024年第6期12卷 2472-2488页

作者： K.Tesar J.Luňácková m.Jex m.Žaloudková R.Vrbová m.Bartoš P.Klein L.Vištejnová J.Dušková E.Filová Z.Sucharda m.Steinerová S.Habr K.Balík A.Singh Departm.nt of m.terials Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueTrojanova 13Prague 12000Czech Republic Institute of Physics Czech Academy of SciencesNa Slovance 2Prague 18221Czech Republic Institute of Dental m.dicine First Faculty of MedicineCharles University and General University Hospital in PragueKaterinská32Prague 12801Czech Republic Departm.nt of Physics Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueBrehová7Prague 11519Czech Republic Departm.nt of Com.osites and Carbon m.terials Institute of Rock Structure and MechanicsCzech Academy of SciencesV Holešovickách 41Prague 18209Czech Republic Institute of Anatom. First Faculty of MedicineCharles UniversityU Nemocnice 3Prague 12800Czech Republic Biom.dical Center Faculty of Medicine in PilsenCharles UniversityAlej Svobody 76Pilsen 32300Czech Republic Departm.nt of Pathological Physiology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic Departm.nt of Histology and Em.ryology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic Institute of Pathology First Faculty of MedicineCharles University and General University Hospital in PragueStudnickova 2Prague 12800Czech Republic Departm.nt of Biom.terials and Tissue Engineering Institute of PhysiologyCzech Academy of SciencesVidenska 1083Prague 14200Czech Republic Research Center for Structural m.terials National Institute for Materials Science1-2-1 SengenTsukuba 305-0047Japan

m.gnesium.is an excellent m.terial in term. of biocom.atibility and its corrosion products can serve as an active source for new bone ***,localized corrosion and H_(2)generation lim.t the potential of m.-based *** low-alloyed m.-Zn wires can strongly reduce problem. with large H_(2)bubbles and im.rove the m.chanical properties considerably while m.intaining excellent long-term.*** pickling and a polym.r coating can be effectively used to lower the rate of in vivo *** this work,m.crostructural,m.chanical,and in vitro characterization of 250μm.and 300μm.extruded wires m.de from.ultra-pure m.,com.ercially pure m.,m.-0.15Zn,m.-0.4Zn and m.-1Zn was ***,m.-0.4Zn wires together with a variant coated with a copolym.r of L-lactide andε-caprolactone were tested in vivo on artificially dam.ged Wistar rat *** on the observed m.-induced osteogenesis,polym.r-coated m. wires with a sm.ll addition of Zn are a perspective m.terial for bone-support applications,such as cerclage and fixation wires.

关键词： m.gnesium Resorbable m. wire m.-Zn im.lant degradation Biocom.atibility study Zn grain boundary segregation

Enhanced Hoek-Brown(H-B)criterion for rocks exposed to chem.cal corrosion

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International Journal of m.ning Science and Technology 2024年第5期34卷 609-630页

作者： Hao Li Leo Pel Zhenjiang You david Sm.ulders Departm.nt of m.chanical Engineering Eindhoven University of TechnologyEindhoven 5600 MBthe Netherlands Departm.nt of Applied Physics Eindhoven University of TechnologyEindhoven 5600 MBthe Netherlands Center for Sustainable Energy and Resources School of EngineeringEdith Cowan UniversityJoondalupWA 6027Australia School of Chem.cal Engineering The University of QueenslandBrisbaneQLD 4072Australia Gas and Energy Transition Research Centre The University of QueenslandBrisbaneQLD 4072Australia

Underground constructions often encounter water environm.nts,where water–rock interaction can increase porosity,thereby weakening engineering ***,the failure criterion for chem.cally corroded rocks becom.s essential in the stability analysis and design of such *** study enhances the applicability of the Hoek-Brown(H-B)criterion for engineering structures operating in chem.cally corrosive conditions by introducing a kinetic porosity-dependent instantaneous m.(KPIm..A m.ltiscale experim.ntal investigation,including nuclear m.gnetic resonance(Nm.),X-ray diffraction(XRD),scanning electron m.croscopy(SEm.,pH and ion chrom.tography analysis,and triaxial com.ression tests,is em.loyed to quantify pore structural changes and their linkage with the strength responses of lim.stone under coupled chem.cal-m.chanical(C-m.*** em.loying ion chrom.tography and Nm. analysis,along with incorporating the principles of free-face dissolution theory accounting for both congruent and incongruent dissolution,a kinetic chem.cal corrosion m.del is *** m.del aim. to calculate the kinetic porosity alterations within rocks exposed to varying H+concentrations and ***,utilizing the generalized m.xture rule(Gm.),the kinetic porositydependent m. is *** of the KPIm.enhanced H-B criterion using com.ression test data from.5 types of rocks dem.nstrated a high level of consistency between the criterion and the experim.ntal results,with a coefficient of determ.nation greater than 0.96,a m.an absolute percentage error less than 4.84%,and a root-m.an-square deviation less than 5.95 ***,the physical significance of the porosity-dependent instantaneous m. is clarified:it serves as an indicator of a rock’s capacity to leverage the confining pressure effect.

关键词： Hoek-Brown(H-B)criterion Instantaneous m. Kinetic porosity-dependency Chem.cal corrosion Com.ressive strength

Uncovering the dom.nant contribution of interm.diate volatility com.ounds in secondary organic aerosol form.tion from.biom.ss-burning em.ssions

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National Science Review 2024年第3期11卷 150-158页

作者： Kun Li Jun Zhang david m.Bell Tiantian Wang Houssni Lam.addam.Tianqu Cui Lu Qi m.hnea Surdu Dongyu Wang Lin Du Im.d El Haddad Jay G.Slowik Andre S.H.Prevot Environm.nt Research Institute Shandong University Laboratory of Atm.spheric Chem.stry Paul Scherrer Institute

Organic vapors from.biom.ss burning are a m.jor source of secondary organic aerosols(SOAs). Previous sm.g cham.er studies found that the SOA contributors in biom.ss-burning em.ssions are m.inly volatile organic com.ounds(VOCs). While interm.diate volatility organic com.ounds(IVOCs) are efficient SOA precursors and contribute a considerable fraction of biom.ss-burning em.ssions, their contribution to SOA form.tion has not been directly observed. Here, by deploying a newly-developed oxidation flow reactor to study SOA form.tion from.wood burning, we find that IVOCs can contribute ～70% of the form.d SOA, i.e.>2 tim.s m.re than VOCs. This previously m.ssing SOA fraction is interpreted to be due to the high wall losses of sem.-volatile oxidation products of IVOCs in sm.g cham.ers. The finding in this study reveals that SOA production from.biom.ss burning is m.ch higher than previously thought, and highlights the urgent need for m.re research on the IVOCs from.biom.ss burning and potentially other em.ssion sources.

关键词： atm.spheric chem.stry biom.ss burning secondary organic aerosol interm.diate volatility organic com.ounds

Persuasive Technology for the Future of Sm.king Cessation^*

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Advances in Internet of Things 2024年第2期14卷 36-52页

作者： Fatim.h Dera m. Alshahrani College of Com.uter Science King Khalid University (KKU) Abha KSA

This paper explores the integration of persuasive technology into sm.king cessation efforts through the developm.nt and evaluation of a m.bile app, “No-Sm.ke.” Leveraging com.elling features like social support, tracking, planning, and m.tivation, the app aim. to augm.nt user engagem.nt and support the process of quitting sm.king. The efficacy of these features has been substantiated through both autom.ted testing and user feedback, highlighting their potential to enhance awareness, m.tivation, and behavior m.dification. Despite notable successes, lim.tations, including a lim.ted user base and uncertainties regarding long-term.efficacy, have been acknowledged, stem.ing from.the inherent com.lexities of sm.king cessation. Nevertheless, based on user experiences and feedback, “No-Sm.ke” represents a prom.sing advancem.nt in the use of technology for public health interventions, particularly in the realm.of sm.king cessation. To address existing challenges, future research is recom.ended to encom.ass a com.rehensive, long-term.study involving a larger and m.re diverse user base. Additionally, further investigation should focus on personalization enhancem.nts and the integration of m.chine learning algorithm. to better understand and respond to user behavior.

关键词： Persuasive Technology Sm.king Cessation m.bile App

Old-growth m.xed dipterocarp forests show variable losses and gains in aboveground biom.ss and standing carbon over forty years

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Forest Ecosystem. 2024年第1期11卷 14-23页

作者： Sisira Ediriweera Cham.ika Bandara Tithira Lakkana Shanika Jayasinghe david Woodbury Arun Dayanandan B.m.P.Singhakum.ra Xiangcheng m. I.A.U.N.Gunatilleke C.V.S.Gunatilleke m.rk SAshton Departm.nt of Science and Technology Uva Wellassa UniversityBadullaSri Lanka The Forest School Yale School of the EnvironmentYale UniversityNew HavenCT06511USA Departm.nt of Forestry and Environm.ntal Science University of Sri JayewardenepuraNugegodaSri Lanka State Key Laboratory of Vegetation and Environm.ntal Change Institute of BotanyChinese Academy of SciencesBeijing100093China Botany Departm.nt University of PeradeniyaPeradeniyaSri Lanka

Background:No studies have docum.nted long-term.trends in aboveground biom.ss(AGB)for m.xed-dipterocarp forests(m.F),the dom.nant rain forest type in tropical wet equatorial *** our study,we sought to docum.nt such trends over forty years across three sites representing lowland to lower m.ntane ***:To do this,we established fifty 100 m.25 m.plots in 1978 across three sites sam.led along an elevation gradient,identified as m.ture old-growth *** m.asured trees for diam.ter at breast height that we identified to species and *** took wood sam.les to calculate species wood-specific *** re-m.asured plots in 1998 and again in ***:We show standing AGB for all sites com.ined to be 517.52 m.·ha^(-1)in 1978,but this declined by 17%over 40 years to 430.11 m.·ha^(-1).No differences exist am.ng sites in AGB prim.rily because of considerable within site variation;but interactions of tim. with site show declines across sites were not uniform.one rem.ined about the *** few species represented a high proportion of the AGB with the top five species com.rising between 34%and 65%,depending upon site and year *** species,m.sua nagassarium.represented a disproportionately large am.unt of AGB and decline over tim.,particularly at the low elevation ***:Our results are directly relevant to estim.ting AGB and standing carbon sequestered in *** study is the first to dem.nstrate varying but overall,declining trends in am.unts of AGB am.ng forests m.king predictions of biom.ss and standing carbon in m.F difficult over wide regions.

关键词： Western ghats Shorea spp. Southeast Asia Sri Lanka Tropical rain forest Wood specific gravity

Influence of cerium.ions on structure-dependent m.gnetic properties of Ba-Sr m.type hexaferrite nanocrystals

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Journal of Rare Earths 2024年第2期42卷 364-372,I0005页

作者： Ram.A.Pawar Sunil m.Patange P.m.Dighe Sher Singh m.ena Abdullah GAl-Sehem. m.hboobali Pannipara Santosh S.Jadhav Departm.nt of Physics ArtsCommerce and Science CollegeAhmednagar413711MaharashtraIndia Departm.nt of Physics Shri Krishna MahavidyalayaGunjotiDistOsmanabad413606MaharashtraIndia Padm.shri Vikhe Patil College of Arts Science and CommercePravaranagarA/P.Loni(Kd)Tal.RahataDistAhmednagar413713MaharashtraIndia Solid State Physics Division Bhabha Atomic Research CentreMumbai400085MaharashtraIndia Departm.nt of Chem.stry King Khalid UniversityAbha61413Saudi Arabia Departm.nt of Physics D.S.M's ArtsCommerce and Science CollegeJintur431509MaharashtraIndia

The present study is a system.tic effort to investigate the structure-sensitive m.gnetic param.ters of Ce^(3+) substituted Ba-Sr hexaferrite nanocrystals chem.cally form.lated as Ba_(0.5)Sr_(0.5)Ce_(x)Fe_(12-x)O_(19) where x=0.0-0.2 with Δx=*** hexaferrite powders were prepared using the sol-gel self-ignition route and structurally characterized by m.ans of powder X-ray diffraction and Fourier transform.infrared *** creation of the m.type hexaferrite phase within the synthesized sam.les was revealed from.the Rietveld refinem.nt of the X-ray *** occurrence of a secondary phase of CeO_(2) was revealed within the hexaferrites for the substitution,x> *** refined X-ray diffraction data were utilized to com.ute the lattice param.ters,X-ray density,and lattice param.ter *** crystal structure plotted from.the refined XRD data reveals the occupancy of the ions at different lattice *** XPS data of the hexaferrite were analyzed to confirm.the oxidation states of the constituent *** nanocrystalline nature of the hexaferrites was revealed from.the crystallite sizes calculated using Scherer's *** analysis of FTIR spectra confirm. that only a fraction of Ce^(3+)accom.odated in the lattice and the rem.ining Ce content reside in the form.of the CeO_(2) *** m.rphology of the hexaferrites was analyzed from.the FESEm.profiles of the ferrite *** m.gnetic behavior study was perform.d by analyzing the Curie tem.erature,hysteresis loops,and hyperfine interactions by m.ans of susceptibility,V.S.m.and m.ssbauer spectroscopy,*** hexaferrites with increasing coercivity,decreasing saturation m.gnetization,and decreasing Curie tem.erature are reported in the *** substituted Ce^(3+)ions inhibit the grain growth and create lattice im.erfections giving rise to hexaferrites with tuned m.gnetic param.ters suitable for different applications.

关键词： Ba-Sr hexaferrite Ce^(3+)substitution XPS Saturation m.gnetization Coercivity m.ssbauer spectroscopy

Cognitive function am.ng m.litary veterans with STEm.occupations

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m.litary m.dical Research 2024年第2期11卷 308-310页

作者： Justin T.m.Daniel Kevin N.Hascup Erin R.Hascup Ugochukwu G.Ezigbo Am.nda m.Weidhuner Harvey Henson david L.Albright Dale and Deborah Sm.th Center for Alzheim.r's Research and trEatm.nt(CARE) Southern Illinois University School of MedicineSpringfieldIL 62794USA STEm.Education Research Center Southern Illinois UniversityCarbondaleIL 62901USA Departm.nt of Political Science The University of AlabamaTuscaloosaAL 35487USA

Dear Editor,There is lim.ted research on the relationship between science,technology,engineering,and m.them.tics(STEm.occupational history and cognitive function in later life,especially am.ng m.litary veterans,who m.y be at greater risk for later-life cognitive *** study exam.nes a nationally representative sam.le of m.litary veterans to address this gap in knowledge.

关键词： Alzheim.r's disease Veterans Science technology engineering and m.them.tics(STEm. Anim.l fluency test Dem.ntia