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Response surface methodology-based optimization of ultrasound-assisted extraction of β-sitosterol and lupeol from Astragalus atropilosus(roots) and validation by HPTLC method

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Asian Pacific Journal of Tropical Biomedicine 2020年第6期10卷 281-292页

作者： Perwez Alam Nasir A.Siddiqui Ali S.Alqahtani Anzarul Haque Omer A.Basudan Saleh I.Alqasoumi m.u.khan Department of Pharmacognosy College of PharmacyKing Saud UniversityP.O.Box-2457Riyadh-11451Saudi Arabia Department of Pharmacognosy College of PharmacyPrince Sattam bin Abdulaziz UniversityAl-KharjKSA Department of Pharmaceutical Chemistry&Pharmacognosy Unaizah College of PharmacyQassim UniversityAl QassimSaudi Arabia

Objective:To optimize the ultrasonication method for efficient extraction ofβ-sitosterol and lupeol from the roots of Astragalus atropilosus using Box-Behnken design of response surface methodology(RSm),and its validation by high performance thin layer chromatography(HPTLC)***:ultrasonication method was used to extractβ-sitosterol and lupeol from Astragalus atropilosus(roots).RSm was used to optimize the different extraction parameters *** to solid ratio(10–14 m L/g),temperature(60-80℃)and time(40–60 min)to maximize the yield ofβ-sitosterol and *** quantitative estimation ofβ-sitosterol and lupeol was done in chloroform extract of Astragalus atropilosus by validated HPTLC method on 10 cm×20 cm glass-backed silica gel 60 F254 plate using hexane and ethyl acetate(8:2,v/v)as mobile ***:A quadratic polynomial model was found to be most appropriate with regard to R1(yield of total extraction;R2/%CV=0.9948/0.28),R2(β-sitosterol yield;R2/%CV=0.9923/0.39)and R3(lupeol yield;R2/%CV=0.9942/0.97).The values of adjusted R2/predicted R2/signal to noise ratio for R1,R2,and R3 were 0.9782/0.9551/48.77,0.9904/0.9110/31.33,and 0.9927/0.9401/36.08,respectively,indicating a high degree of correlation and adequate *** linear correlation plot between the predicted and experimental values for R1,R2,and R3 showed high values of R2 ranging from 0.9905-0.9973.β-sitosterol and lupeol in chloroform extract of Astragalus atropilosus were detected at Rf values of 0.22 and 0.34,respectively,atλmax=518 *** optimized ultrasonic extraction produced 8.462%w/w of R1,0.451%w/w of R2 and 0.172%w/w of R3 at 13.5 m L/g liquid to solid ratio,78℃of temperature and 60 min of ***:The experimental findings of RSm optimized extraction and HPTLC analysis can be further applied for the efficient extraction ofβ-sitosterol and lupeol in other species of Astragalus.

关键词： β-sitosterol Lupeol Box-Behnken design Astragalus High performance thin layer chromatography

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Symmetries,optimal system,exact and soliton solutions of(3+1)-dimensional Gardner-KP equation

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Journal of Ocean Engineering and Science 2024年第2期9卷 178-190页

作者： Amjad Hussain Ashreen Anjum m.Junaid-u-Rehman Ilyas khan mariam A.Sameh Amnah S.Al-Johani Department of mathematics Quaid-I-Azam University 45320Islamabad 44000Pakistan Department of mathematics College of Science Al-ZulfiMajmaah UniversityAl-MajmaahP.O Box 66Majmaah 11952Saudi Arabia Electrical Engineering Department Faculty of Engineering and TechnologyFuture University in EgyptNew Cairo 11845Egypt mathematics Department Faculty of ScienceUniversity of TabukTabukSaudi Arabia

In this research article,the(3+1)-dimensional nonlinear Gardner-Kadomtsov-Petviashvili(Gardner-KP)equation which depicts the nonlinear modulation of periodic waves,is analyzed through the Lie group-theoretic *** the Lie invariance condition,we find the symmetry *** pro-posed model yields eight-dimensional Lie ***,an optimal system of sub-algebras is com-puted,and similarity reductions are *** considered nonlinear partial differential equation is re-duced into ordinary differential equations(ODEs)by utilizing the similarity transformation method(STm),which has the benefit of yielding a large number of accurate traveling wave *** ODEs are further solved to get closed-form solutions of the Gardner-KP equation in some cases,while in other cases,we use the new auxiliary equation method to get its soliton *** evolution profiles of the obtained solutions are examined graphically under the appropriate selection of arbitrary parameters.

关键词： Gardner-KP equation Lie symmetry analysis Optimal system New auxiliary equation method Solitary wave solutions

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In search of a pan-coronavirus vaccine:next-generation vaccine design and immune mechanisms

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Cellular & molecular Immunology 2024年第2期21卷 103-118页

作者： S.Cankat m.u.Demael L.Swadling Division of Infection and Immunity Institute of Immunity and TransplantationUniversity College LondonPears BuildingLondon NW32PPUK

members of the coronaviridae family are endemic to human populations and have caused several epidemics and pandemics in recent *** this review,we will discuss the feasibility of and progress toward the ultimate goal of creating a pan-coronavirus vaccine that can protect against infection and disease by all members of the coronavirus *** will detail the unmet clinical need associated with the continued transmission of SARS-CoV-2,mERS-CoV and the four seasonal coronaviruses(HCoV-OC43,NL63,HKu1 and 229E)in humans 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 immunity to coronaviruses and have informed next-generation vaccine *** will then consider the ideal properties of a pan-coronavirus vaccine and propose a blueprint for the type of immunity that may 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 immunity Cross-protection universal

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Twinning aspects and their efficient roles in wrought mg alloys:A comprehensive review

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Journal of magnesium and Alloys 2024年第6期12卷 2201-2230页

作者： S.S.A.Shah manping Liu Azim khan Farooq Ahmad m.R.Abdullah Xingquan Zhang Shiwei Xu Zhen Peng School of materials Science and Engineering Jiangsu UniversityZhenjiang 212013China School of mechanical Engineering Anhui University of TechnologyMáanshan 243002China College of mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China

Twinning is widely recognized as an effective and cost-efficient method for controlling the microstructure and properties of wrought magnesium(mg)***,twins play a crucial role in initiating dynamic recrystallization(DRX),while twin regions experience rapid recrystallization during static recrystallization(SRX).The activation of twinning can lead to changes in lattice orientation,significantly impacting the final texture in mg *** active roles of twinning are influenced by various factors during the activation process,and the mobility of twin boundaries(TB)can be amplified by stress effects,dislocation interactions,and thermal ***,annealing treatments that involve proper segregation or precipitation on TBs serve to stabilize them,restraining their *** such as segregation may also alter the twinning propensity in magnesium-rare earth(mg-RE)***{10–11}contraction twins(CT)and{10–11}-{10–12}double twins(DT)can promote dynamic recrystallization(DRX),they also pose a risk as potential sources of voids and ***,understanding the nucleation and growth mechanisms of twinning is crucial,and these aspects are briefly reviewed in this *** the factors mentioned above,this article summarizes the recent research progress in this field,shedding light on advancements in recent eras.

关键词： mg alloys Twinning Recrystallization Texture mechanical properties

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Stability analysis and soliton solutions of the(1+1)-dimensional nonlinear chiral Schrodinger equation in nuclear physics

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Communications in Theoretical Physics 2024年第9期76卷 1-15页

作者： Fazal Badshah Kalim u Tariq Ahmet Bekir S m Raza Kazmi Emad Az-Zo'bi School of Electrical and Information Engineering Hubei University of Automotive TechnologyShiyan 442002China Department of mathematics Mirpur University of Science and TechnologyMirpur-10250(AJK)Pakistan Neighbourhood of Akcaglan Imarli StreetNumber:28/426030EskisehirTurkey Department of mathematics and Statistics Faculty of ScienceMutah UniversityAlKarak 61710Jordan

The nonlinear Schrodinger equation equation is one of the most important physical models used in optical fiber theory to explain the transmission of an optical *** field of chiral soliton propagation in nuclear physics is very interesting because of its numerous applications in communications and ultra-fast signal routing ***(1+1)-dimensional chiral dynamical structure that describes the soliton behaviour in data transmission is dealt with in this work using a variety of in-depth analytical *** work has applications in particle physics,ionised science,nuclear physics,optics,and other applied mathematical *** are able to develop a variety of solutions to demonstrate the behaviour of solitary wave structures,periodic soliton solutions,chiral soliton solutions,and bell-shaped soliton solutions with the use of applied ***,in order to verify the scientific calculations,the stability analysis for the observed solutions of the governing model is taken into *** addition,the3-dimensional,contour,and 2-dimensional visuals are supplied for a better understanding of the behaviour of the *** employed strategies are dependable,uncomplicated,and effective;yet have not been utilised with the governing model in the literature that is now *** resulting outcomes have impressive applications across a large number of study areas and computational physics phenomena representing real-world *** methods applied in this model are not utilized on the given models in previous literature so we can say that these describe the novelty of the work.

关键词： solitons the nonlinear Schrodinger equation stability analysis chiral solitons exact solutions

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Hybrid-Vlasov simulation of soft X-ray emissions at the Earth’s dayside magnetospheric boundaries

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Earth and Planetary Physics 2024年第1期8卷 70-88页

作者： m.Grandin H.K.Connor S.Hoilijoki m.Battarbee Y.Pfau-Kempf u.Ganse K.Papadakis m.Palmroth Department of Physics University of HelsinkiHelsinkiFinland NASA Goddard Space Flight Center GreenbeltMD20771USA Space and Earth Observation Centre Finnish Meteorological InstituteHelsinkiFinland

Solar wind charge exchange produces emissions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by remote sensing *** Solar wind magnetosphere Ionosphere Link Explorer(SmILE)and Lunar Environment heliospheric X-ray Imager(LEXI)missions aim to obtain soft Xray images of near-Earth space thanks to their Soft X-ray Imager(SXI)*** earlier modeling works have already simulated soft X-ray images as might be obtained by SmILE SXI during its mission,the numerical models used so far are all based on the magnetohydrodynamics description of the space *** investigate the possible signatures of ion-kinetic-scale processes in soft Xray images,we use for the first time a global hybrid-Vlasov simulation of the geospace from the Vlasiator *** simulation is driven by fast and tenuous solar wind conditions and purely southward interplanetary magnetic *** first produce global X-ray images of the dayside near-Earth space by placing a virtual imaging satellite at two different locations,providing meridional and equatorial *** then analyze regional features present in the images and show that they correspond to signatures in soft X-ray emissions of mirrormode wave structures in the magnetosheath and flux transfer events(FTEs)at the *** results suggest that,although the time scales associated with the motion of those transient phenomena will likely be significantly smaller than the integration time of the SmILE and LEXI imagers,mirror-mode structures and FTEs can cumulatively produce detectable signatures in the soft X-ray *** instance,a local increase by 30%in the proton density at the dayside magnetopause resulting from the transit of multiple FTEs leads to a 12%enhancement in the line-of-sight-and time-integrated soft X-ray emissivity originating from this ***,a proton density increase by 14%in the magnetosheath

关键词： magnetosphere magnetosheath numerical simulation SmILE LEXI soft X-ray emissions hybrid-Vlasov model polar cusp flux transfer events mirror-mode waves

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Exact solutions for magnetohydrodynamic nanofluids flow and heat transfer over a permeable axisymmetric radially stretching/shrinking sheet

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Chinese Physics B 2024年第2期33卷 108-114页

作者： u.S.mahabaleshwar G.P.Vanitha L.m.Pérez Emad H.Aly I.Pop Department of Studies in mathematics Davangere UniversityShivagangothriDavangereIndia Departamento de F´ısica FACIUniversidad de Tarapac´aCasilla 7DAricaChile Department of mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt Department of mathematics Babes-Bolyai University400084 Cluj-NapocaRomania

We report on the magnetohydrodynamic impact on the axisymmetric flow of Al_(2)O_(3)/Cu nanoparticles suspended in H_(2)O past a stretched/shrinked *** the use of partial differential equations and the corresponding thermophysical characteristics of nanoparticles,the physical flow process is *** resultant nonlinear system of partial differential equations is converted into a system of ordinary differential equations using the suitable similarity *** transformed differential equations are solved *** of the magnetic parameter,solid volume fraction and stretching/shrinking parameter on momentum and temperature distribution have been analyzed and interpreted *** skin friction and Nusselt number were also *** addition,existence of dual solution was deduced for the shrinking sheet and unique solution for the stretching ***,Al_(2)O_(3)/H_(2)O nanofluid flow has better thermal conductivity on comparing with Cu/H_(2)O ***,it was found that the first solutions of the stream are stable and physically realizable,whereas those of the second ones are unstable.

关键词： magnetohydrodynamic nanofluid stretching/shrinking sheet axisymmetric flow analytical solution suction/injection

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Fuzzy and IRLNC-based routing approach to improve data storage and system reliability in IoT

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Intelligent and Converged Networks 2024年第1期5卷 68-80页

作者： u.Indumathi A.R.Arunachalam the Department of Computer Science and Engineering Dr.M.G.R.Educational and Research InstituteChennai 600095India

Internet of Things(IoT)based sensor network is largely utilized in various field for transmitting huge amount of data due to their ease and cheaper *** performing this entire process,there is a high possibility for data corruption in the mid of *** the other hand,the network performance is also affected due to various *** address these issues,an efficient algorithm that jointly offers improved data storage and reliable routing is ***,after the deployment of sensor nodes,the election of the storage node is achieved based on a fuzzy expert *** Random Linear Network Coding(IRLNC)is used to create an encoded *** encoded packet from the source and neighboring nodes is transmitted to the storage ***,to transmit the encoded packet from the storage node to the destination shortest path is found using the Destination Sequenced Distance Vector(DSDV)*** analysis of the proposed work is carried out by evaluating some of the statistical *** residual energy,packet delivery ratio,compression ratio and storage time achieved for the proposed work are 8.8%,0.92%,0.82%,and 69 *** on this analysis,it is revealed that better data storage system and system reliability is attained using this proposed work.

关键词： Internet of Things(IoT) data storage management fuzzy system improved random linear network coding energy utilization system reliability

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Promotion of structural plasticity in area V2 of visual cortex prevents against object recognition memory deficits in aging and Alzheimer's disease rodents

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Neural Regeneration Research 2024年第8期19卷 1835-1841页

作者： Irene Navarro-Lobato mariam masmudi-martín manuel F.López-Aranda Juan F.López-Téllez Gloria Delgado Pablo Granados-Durán Celia Gaona-Romero marta Carretero-Rey Sinforiano Posadas maría E.Quiros-Ortega Zafar u.khan Laboratory of Neurobiology Centro de Investigaciones Médico Sanitarias(CIMES)University of MalagaMalagaSpain Department of medicine Faculty of MedicineUniversity of MalagaMalagaSpain Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas(CIBERNED) Institute of Health Carlos IIIMadridSpain the Donders Institute for Brain Cognition and Behaviour Radboud UniversityNijmegenThe Netherlands the Brain metastasis Group National Cancer Research Centre(CNIO)MadridSpain the Department of Neurobiology University of California-Los AngelesLos AngelesCAUSA

memory deficit,which is often associated with aging and many psychiatric,neurological,and neurodegenerative diseases,has been a challenging issue for *** till now,all potential drug candidates have failed to produce satisfa ctory ***,in the search for a solution,we found that a treatment with the gene corresponding to the RGS14414protein in visual area V2,a brain area connected with brain circuits of the ventral stream and the medial temporal lobe,which is crucial for object recognition memory(ORm),can induce enhancement of *** this study,we demonstrated that the same treatment with RGS14414in visual area V2,which is relatively unaffected in neurodegenerative diseases such as Alzheimer s disease,produced longlasting enhancement of ORm in young animals and prevent ORm deficits in rodent models of aging and Alzheimer’s ***,we found that the prevention of memory deficits was mediated through the upregulation of neuronal arbo rization and spine density,as well as an increase in brain-derived neurotrophic factor(BDNF).A knockdown of BDNF gene in RGS14414-treated aging rats and Alzheimer s disease model mice caused complete loss in the upregulation of neuronal structural plasticity and in the prevention of ORm *** findings suggest that BDNF-mediated neuronal structural plasticity in area V2 is crucial in the prevention of memory deficits in RGS14414-treated rodent models of aging and Alzheimer’s ***,our findings of RGS14414gene-mediated activation of neuronal circuits in visual area V2 have therapeutic relevance in the treatment of memory deficits.

关键词： behavioral performance brain-derived neurotrophic factor cognitive dysfunction episodic memory memory circuit activation memory deficits memory enhancement object recognition memory prevention of memory loss regulator of G protein signaling

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Latest Carboniferous-Early Permian Rifting of the Northern Gondwanan margin and the Opening of the Northern Neotethys: New Evidence from the Carboniferous and Permian Foraminiferal Assemblages from the Beyşehir-Hoyran Nappes, Central Taurides(Southern Turkey)

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Journal of Earth Science 2024年第2期35卷 394-415页

作者： Cengiz Okuyucu u.Kagan Tekin Cagri Guzgun Kaan Sayit Department of Geological Engineering Konya Technical UniversityKonya42250Turkey Department of Geological Engineering Hacettepe UniversityAnkara06800Turkey Department of Geological Engineering Middle East Technical UniversityAnkara06800Turkey

The Beyşehir-Hoyran Nappes,one of the tectonostratigraphic units of the Taurides,are thought to be originated from the Izmir-Ankara Ocean(northern branch of Neotethys).In this study,Late Paleozoic rock units from the blocks of Beyşehir-Hoyran Nappes were studied in detail using foraminiferal assemblages in two different locations from the southwest of Karaman City(southern Turkey).In both places,blocks/slices and pebbles of various origins are embedded within a highly sheared matrix of Late Cretaceous Age,and the whole unit can be regarded as a sedimentary mé*** ages of the blocks from the southwest of Karaman City range from the Late Serpukhovian(Late mississippian)to Late Capitanian(middle Permian)with some depositional breaks(e.g.,Bashkirian,Kasimovian).Combined with the previous data from the mersin mélange,which also include the remnants of the Beyşehir-Hoyran Nappes,our new findings suggest that a shallowing-upward sequence,characterized by a shallow water environment with foraminifera-bearing limestones,was deposited over the Tournaisian pelagic sequence in the Beyşehir-Hoyran Nappes till the Early moscovian(Early middle Pennsylvanian).This shallowing-upward sequence in the Beyşehir-Hoyran Nappes could be related to the Late Paleozoic Glaciation on the Gondwana supercontinent(Glacial Ⅱ),which resulted in a sea-level drop and deposition of platform carbonates during the Viséan–Early moscovian(middle mississippian to Early middle Pennsylvanian)time *** absence of the main part of the middle-upper Pennsylvanian deposits(continental phase during the middle moscovian–middle Gzhelian)in the Beyşehir-Hoyran Nappes can be mainly attributed to the occurrence of a mantle plume and partially to the effect of Late Paleozoic Gondwanan Glaciation(Glacial Ⅲ).Progressive uplifting by the buoyant mantle plume material has resulted in rifting at the center of the basin where the Beyşehir-Hoyran Nappes have *** rifting process led to tectonic destabiliz

关键词： foraminifera Carboniferous and Permian Beyşehir-Hoyran Nappes plume rifting Neotethys paleontology

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