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steroids, Tri- and m.roterpenoids with a Quinone structure—A Review

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International Journal of Organic Chem.stry 2024年第1期14卷 32-68页

作者： m.ryam.s. m. Aghaei Thies Thiem.nn Departm.nt of Chem.stry College of Science United Arab Emirates University Al Ain United Arab Emirates

Terpenoids with quinoid structures are found as natural products. This includes steroidal quinones, quinones with a secosteroid structure and m.roterpenoid quinones. Im.ortantly, catechol estrogens as endogenous m.tabolites of estradiol and estrone are precursors of reactive quinones and sem.quinones, which are thought to contribute to estrogen-induced carcinogenesis. On the other hand, a num.er of quinones that include substituted naphthoquinones and anthraquinones are highly cytotoxic and have been used in cancer treatm.nt. This m.kes the structures interesting synthetic targets. The following is a review of im.ortant natural and synthetic terpenoid and steroid quinone hybrids.

关键词： steroid secosteroid m.roterpenoid Triterpenoid Quinone Anti-Tum.ur Agent Antibiotic Natural Product

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

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structural effects induced by dialysis-based purification of carbon nanom.terials

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Nano m.terials science 2024年第4期6卷 475-483页

作者： A.D.Veloso A.m.Ferraria A.m.Botelho do Rego A.s.Viana A.J.s.Fernandes A.J.Fielding R.A.Videira m.C.Oliveira CQ-VR and Chem.stry Departm.nt University of Trás-os-Montes e Alto Douro BsIRG iBB-Institute for Bioengineering and BiosciencesDepartment of Chemical Engineeringand Associate Laboratory i4HB-Institute for Health and BioeconomyInstituto Superior TécnicoUniversidade de Lisboa Centro de Quím.ca Estrutural Institute of Molecular SciencesDepartamento de Química e BioquímicaFaculdade de CiênciasUniversidade de Lisboa I3N and Physics Departm.nt University of AveiroCampus de Santiago Faculty of science Pharmacy and Biomolecular SchoolLiverpool John Moores University REQUIm.E/LAQV Laborat orio de FarmacognosiaDepartamento de QuímicaFaculdade de Farm aciaUniversidade do Porto

Dialysis plays a crucial role in the purification of nanom.terials but its im.act on the structural properties of carbon nanom.terials was never ***,a carbon-based nanom.terial generated electrochem.cally in potassium.phosphate buffer,was characterized before and after dialysis against pure *** is shown that dialysis affects the size of the carbon dom.ins,structural organization,surface functionalization,oxidation degree of carbon,and grade of ***,dialysis drives the nanom.terial organization from.discrete roundish carbon dom.ins,with sizes ranging from.70 to 160 nm.towards linear stacking structures of sm.ll nanoparticles （m..In parallel,alcohol and ether （epoxide） surface groups evolve into m.re oxidized carbon groups （e.g.,ketone and ester groups）.Investigation of the as-prepared nanom.terial by electron param.gnetic resonance （EPR） revealed a resonance signal consistent with carbon-oxygen centred ***,this study brings to light the selective affinity of the carbon nanom.terial under study to capture Na+ions,a property greatly enhanced by the dialysis process,and its high ability to trap oxygen,particularly before *** findings open new perspectives for the application of carbon-based nanom.terials and raise awareness of the im.ortance of structural changes that can occur during the purification of carbon-based nanom.terials.

关键词： Nanocarbon surface functionalization Nm. XPs Hydrophilic carbon Param.gnetic

Large m.gnetocaloric effect and m.gnetic properties of EuRhO3

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Journal of Rare Earths 2024年第9期42卷 1724-1729页

作者： m.Lassri m.sajieddine A.Elouafi A.El Hachm. s.El Ouahbi R.m.ubah Laboratory of Energy and m.terials Engineering (LGEm. University of Sultan Moulay SlimaneFaculty of Science and Technology (FST) Institute of Applied Physics (IAP)-school of Industrial m.nagem.nt (Em.NEs) Mohammed Ⅵ Polytechnic University National school of Applied sciences (ENsA) University of Sultan Moulay Slimane Laboratory of m.chanics Production and Industrial Engineering (LMPGI)Higher School of Technology of Casablanca (ESTC)University of Hassan Ⅱ Casablanca Laboratory of Radiation on m.tter and Instrum.ntation (LRm.) Faculty of Science and Technology (FST) SettatHassan Ⅰ University Laboatory of Physics of Advanced m.terials and Therm.c (LPm.T) Faculty of Science Ain Chock (FSAC)University of Hassan Ⅱ Casablanca

We report on the structural,m.gnetic,and m.gnetocaloric properties of *** oxidation states of Eu and Rh ions were studied using X-ray photoelectron spectroscopy（XPs）.It is found that the Eu ions are m.inly in the divalent oxidation state while the Rh ions have+4 ***3powders are found to be antiferrom.gnetic with a second order m.gnetic transition at Neel tem.erature（TN=2.9 K）.Analysis of the m.gnetic susceptibility versus tem.erature data in term. of the Curie=Weiss law:(χ=C/（T-θW）) for T>TN,yields θW=-3.1 K and effective m.gne tic m.m.nt ■,which is close to the theoretical value ■.The m.gnetic entropy change(-Δsm.,was determ.ned by em.ploying the therm.dynam.ic m.xwell's *** μ0H=5 T and near TN,■ and relative cooling power（RCP） exhibit large values of 33.7 J/（kg·K） and 238 J/kg,*** large m.gnitude of-Δsm.nd RCP show that the EuRhO3com.ound could be a potential candidate to be used in cryogenic m.gnetic refrigeration.

关键词： Cryogenic m.gnetic refrigeration m.gnetic properties m.gnetocaloric effect Rare earths X-ray photoelectron spectroscopy

Com.utational Fluid Dynam.cs Approach for Predicting Pipeline Response to Various Blast scenarios: A Num.rical m.deling study

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Com.uter m.deling in Engineering & sciences 2024年第9期140卷 2747-2777页

作者： Farm.n saifi m.hd Javaid Abid Haleem.s.m.Anas Departm.nt of m.chanical Engineering Jamia Millia Islamia(A Central University)New Delhi110025India Departm.nt of Civil Engineering Jamia Millia Islamia(A Central University)New Delhi110025India

Recent industrial explosions globally have intensified the focus in m.chanical engineering on designing infras-tructure system. and networks capable of withstanding blast *** centered on high-profile facilities such as em.assies and petrochem.cal plants,this concern now extends to a wider array of infrastructures and *** and scholars increasingly prioritize structural safety against explosions,particularly to prevent disproportionate collapse and dam.ge to nearby *** has further am.lified the reliance on oil and gas pipelines,m.king them.vital for urban life and prim. targets for terrorist ***,there is a growing im.erative for com.utational engineering solutions to tackle blast loading on pipelines and m.tigate associated risks to avert *** this study,an em.ty pipe m.del was successfully validated under contact blast conditions using Abaqus software,a powerful tool in m.chanical engineering for sim.lating blast effects on buried *** a Eulerian-Lagrangian com.utational fluid dynam.cs approach,the investigation extended to above-surface and below-surface blasts at standoff distances of 25 and 50 *** descriptions in the num.rical m.del relied on Abaqus’default m.chanical *** analysis revealed varying pipe perform.nce,with deform.tion decreasing as explosion-to-pipe distance *** explosion’s location relative to the pipe surface notably influenced deform.tion levels,a key finding highlighted in the ***,quantitative findings indicated varying ratios of plastic dissipation energy(PDE)for different blast scenarios com.ared to the contact blast(P0).specifically,P1(25 m. subsurface blast)and P2(50 m. subsurface blast)showed approxim.tely 24.07%and 14.77%of P0’s PDE,respectively,while P3(25 m. above-surface blast)and P4(50 m. above-surface blast)exhibited lower PDE values,accounting for about 18.08%and 9.67%of P0’s PDE,***

关键词： Blast loading com.utational fluid dynam.cs com.uter m.deling pipe networks response prediction structural safety

Credit Card Fraud Detection Using Im.roved Deep Learning m.dels

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Com.uters, m.terials & Continua 2024年第1期78卷 1049-1069页

作者： sum.ya s.sulaim.n Ibraheem.Nadher sarab m.Ham.ed Com.uter science Departm.nt Al-Mustansiriya UniversityBaghdad10001Iraq Com.uter science Departm.nt University of BaghdadBaghdad10001Iraq Faculty of Basic Education Al-Mustansiriya UniversityBaghdad10001Iraq

Fraud of credit cards is a m.jor issue for financial organizations and *** fraudulent actions becom. m.re com.lex,a dem.nd for better fraud detection system. is *** learning approaches have shown prom.se in several fields,including detecting credit card ***,the efficacy of these m.dels is heavily dependent on the careful selection of appropriate *** paper introduces m.dels that integrate deep learning m.dels with hyperparam.ter tuning techniques to learn the patterns and relationships within credit card transaction data,thereby im.roving fraud *** deep learning m.dels:AutoEncoder(AE),Convolution Neural Network(CNN),and Long short-Term.m.m.ry(LsTm.are proposed to investigate how hyperparam.ter adjustm.nt im.acts the efficacy of deep learning m.dels used to identify credit card *** experim.nts conducted on a European credit card fraud dataset using different hyperparam.ters and three deep learning m.dels dem.nstrate that the proposed m.dels achieve a tradeoff between detection rate and precision,leading these m.dels to be effective in accurately predicting credit card *** results dem.nstrate that LsTm.significantly outperform.d AE and CNN in term. of accuracy(99.2%),detection rate(93.3%),and area under the curve(96.3%).These proposed m.dels have surpassed those of existing studies and are expected to m.ke a significant contribution to the field of credit card fraud detection.

关键词： Card fraud detection hyperparam.ter tuning deep learning autoencoder convolution neural network long short-term.m.m.ry resam.ling

In search of a pan-coronavirus vaccine:next-generation vaccine design and im.une m.chanism.

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Cellular & m.lecular Im.unology 2024年第2期21卷 103-118页

作者： s.Cankat m.U.Dem.el L.swadling Division of Infection and Im.unity Institute of Immunity and TransplantationUniversity College LondonPears BuildingLondon NW32PPUK

m.m.ers of the coronaviridae fam.ly are endem.c to hum.n populations and have caused several epidem.cs and pandem.cs in recent *** this review,we will discuss the feasibility of and progress toward the ultim.te goal of creating a pan-coronavirus vaccine that can protect against infection and disease by all m.m.ers of the coronavirus *** will detail the unm.t clinical need associated with the continued transm.ssion of sARs-CoV-2,m.Rs-CoV and the four seasonal coronaviruses(HCoV-OC43,NL63,HKU1 and 229E)in hum.ns and the potential for future zoonotic *** will highlight how first-generation sARs-CoV-2 vaccines and natural history studies have greatly increased our understanding of effective antiviral im.unity to coronaviruses and have inform.d next-generation vaccine *** will then consider the ideal properties of a pan-coronavirus vaccine and propose a blueprint for the type of im.unity that m.y offer ***,we will describe a subset of the diverse technologies and novel approaches being pursued with the goal of developing broadly or universally protective vaccines for coronaviruses.

关键词： Vaccine Coronavirus Cross-reactive im.unity Cross-protection Universal

Acceleration of solar wind particles due to inertial Alfvén waves

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Com.unications in Theoretical Physics 2024年第6期76卷 137-141页

作者： Kiran Batool Im.an A Khan m.shamir Abdul Kabir s Ayaz Theoretical Physics Departm.nt National Centre for PhysicsIslamabad 44000Pakistan Departm.nt of space sciences Institute of Space TechnologyIslamabad 44000Pakistan space and Astrophysics Research Lab(sARL) National Center of GIS and Space Applications(NCGSA)Islamabad 44000Pakistan salam.Chair Department of PhysicsGC University LahoreKatchery RoadLahorePunjab 54000Pakistan Departm.nt of space science and CsPAR University of Alabama in HuntsvilleHuntsvilleAL 35899United States of America

Gaining an understanding of the effects and dynam.cs of the solar wind is crucial for the study of space weather,Earth's m.gnetosphere,spacecraft protection,the dynam.cs of the solar system.and various other *** show that Alfvén waves effectively transfer energy to resonant *** study dem.nstrates how inertial Alfvén waves deliver their energy to resonant plasm. particles in different solar environm.nts under certain *** analysis shows that inertial Alfvén waves experience m.re rapid dam.ing with increasing parallel wavenum.er,am.ient m.gnetic field strength,and particle num.er density,coupled with a decrease in *** rate of energy transfer to resonant particles intensifies with higher tem.eratures and reduced parallel wavenum.er and particle num.er *** with higher initial velocities actively participate in Landau dam.ing,especially in regions with a stronger am.ient m.gnetic field.

关键词： solar wind inertial Alfven waves resonant particles

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m.ltiple scales m.thod for analyzing a forced dam.ed rotational pendulum.oscillatorwithgallows

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Com.unications in Theoretical Physics 2024年第5期76卷 58-67页

作者： Haifa A Alyousef Alvaro H salas B m.Alotaibi s A El-Tantawy Departm.nt of Physics College of SciencePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia Departm.nt of m.them.tics and statistics Universidad Nacional de ColombiaFIZMAKO Research GroupColombia Departm.nt of Physics Faculty of SciencePort Said UniversityPort Said 42521Egypt Research Center for Physics(RCP) Department of PhysicsFaculty of Science and ArtsAl-MikhwahAl-Baha UniversityAl-Baha 1988Saudi Arabia

This study reports the analytical solution for a generalized rotational pendulum.system.with gallows and periodic excited *** m.ltiple scales m.thod(m.m.is applied to solve the proposed *** types of rotational pendulum.oscillators are studied and talked about in *** include the forced dam.ed rotating pendulum.oscillator with gallows,the dam.ed standard sim.le pendulum.oscillator,and the dam.ed rotating pendulum.oscillator without *** m.m.first-order approxim.tions for all the cases m.ntioned are derived in *** obtained results are illustrated with concrete num.rical *** first-order m.m.approxim.tions are com.ared to the fourth-order Runge-Kutta(RK4)num.rical ***,the m.xim.m.error is estim.ted for the first-order approxim.tions obtained through the m.m.com.ared to the num.rical approxim.tions obtained by the RK4 ***,we conducted a com.arative analysis of the outcom.s obtained by the used m.thod(m.m.and He-m.m.to ascertain their respective levels of *** proposed m.thod can be applied to analyze m.ny strong nonlinear oscillatory equations.

关键词： rotational pendulum.system m.ltiple scales m.thod approxim.te solution dam.ed oscillations forced pendulum.with gallows he-m.ltiple scales m.thod

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