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Anisotropic extensions of isotropic Finch–Skea metric in the charged modified gravity

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Communications in Theoretical Physics 2024年第9期76卷 118-140页

作者： Tayyab Naseer m Sharif Department of mathematics and Statistics The University of Lahore1-Km Defence RoadLahore 54000Pakistan

In this study,we explore the Finch–Skea perfect fluid solution and extend its domain to three distinct anisotropic interior models within the framework of the f(R,T)theory,incorporating the influence of an electromagnetic *** assume a static spherical spacetime initially coupled with an isotropic matter *** then introduce a Lagrangian corresponding to an additional gravitating source,taking into account its role in inducing pressure anisotropy within the original fluid *** deriving the field equations for the combined matter setup,we applied a radial component transformation,which yielded two distinct systems of *** addition,we consider a charged exterior spacetime to determine the three constants associated with the Finch–Skea solution at the *** findings suggest that under certain parametric choices,all three resulting models exhibited physical relevance within this modified theory.

关键词： anisotropy modified gravity gravitational decoupling

Embracing substrate multispecificity in plant ABC transporters

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molecular Plant 2024年第7期17卷 990-992页

作者： markus m.Geisler Department of Biology University of Fribourg1700 FribourgSwitzerland

By analogy,the first plant ATP-binding cassette(ABC)transporters were identified as vacuolar detoxifiers transporting glutathione conjugates into the vacuole(martinoia et al.,1993).This somewhat negative image as"unspecific detoxifiers"still clings to plant ABC transporters today,although they have since been described to be involved in completely different programs,including development and defense(Park et al.,2017).In this context,some key plant ABC transporters have been shown to own exceptionally high substrate *** example,the transporter of the native auxin indole-3-acetic acid(IAA),Arabidopsis ABCB1,has been shown to also export the synthetic auxin 1-naphtaleneacetic acid but is even able to distinguish this substrate from its structural isomer,2-naphtaleneacetic acid(Geisler et al.,2005).Likewise,ABCG36 and ABCG37,which are known to have a broader substrate portfolio(Park et al.,2017;Aryal et al.,2023),export IBA but do not touch IAA(Aryal et al.,2023).Recently,several reports have challenged our current view on the reported high substrate specificity of plant ABCs,which requires clarification.

关键词： specificity analogy exceptional

Gedunin attenuates streptozotocin-induced diabetic hepatopathy in rats

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Asian Pacific Journal of Tropical Biomedicine 2024年第7期14卷 288-297页

作者： Suchismita mazumdar Thankamani m marar Jyoti m Patki School of Biotechnology and Bioinformatics D.Y.Patil Deemed to be UniversityNavi Mumbai 400614India

Objective:To examine the hepatoprotective effects of gedunin in streptozotocin(STZ)-induced diabetic ***:Rats were divided into 4 groups:control,STZ,gedunin,and STZ+*** parameters for liver function and liver histology were *** molecular interaction of gedunin with the liver glucose transporters GLUT2 and SGLT1 was examined using AutoDock ***:Gedunin attenuated STZ-induced increase in the levels of aspartate transaminase,alanine transaminase,alkaline phosphatase,lactate dehydrogenase and gamma-glutamyl transferase in the serum and liver tissue,reduced lipid peroxidation,and enhanced antioxidant *** studies showed considerable restoration of liver architecture in gedunin-treated diabetic *** silico studies revealed stable binding of gedunin with GLUT2 and ***:Gedunin exerts hepatoprotective effects in STZ-induced diabetic rats by reducing liver enzymatic activities and oxidative *** studies are warranted to verify the mechanism of its hepatoprotective action.

关键词： Gedunin GLUT2 SGLT1 Diabetic hepatopathy Docking Histology Homology modelling

Wear dependent virtual flow rate sensor for progressing cavity pumps with deformable stator

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Petroleum Science 2024年第2期21卷 1346-1353页

作者： Jens müller Sebastian Leonow Johannes Schulz Christian Hansen martin monnigmann Ruhr-Universitat Bochum Universit atsstraûe 150Bochum44801Germany SEEPEX GmbH Scharnh olzstraûe 344Bottrop46240Germany

This contribution presents a novel wear dependent virtual flow rate sensor for single stage single lobe progressing cavity pumps. We study the wear-induced material loss of the pump components and the impact of this material loss on the volumetric efficiency. The results are combined with an established backflow model to implement a backflow calculation procedure that is adaptive to wear. We use a laboratory test setup with a highly abrasive fluid and operate a pump from new to worn condition to validate our approach. The obtained measurement data show that the presented virtual sensor is capable of calculating the flow rate of a pump being subject to wear during its regular operation.

关键词： Backflow Progressing cavity pump Virtual sensor Wear

Tensile deformation of fine-grained mg at 4K,78K and 298K

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Journal of magnesium and Alloys 2024年第6期12卷 2534-2556页

作者： m.Walag A.Kula P.Noga T.Tokarski G.Cios m.Niewczas AGH University of Krakow Faculty of Non-Ferrous MetalsKrakowPoland AGH University of Krakow Academic Centre for Materials and NanotechnologyKrakowPoland materials Science and Engineering McMaster UniversityHamiltonCanada

The impact of grain size, ranging from 0.9 μm to 9 μm, on the mechanical properties of commercially pure mg is investigated at temperatures of 4K, 78K, and 298K. The mechanisms governing plastic flow are influenced by both grain size and temperature. At 4K and 78K, dominant deformation modes in mg involve dislocation glide and extension twinning, regardless of grain size. The interactions between basal and non-basal dislocations and dislocations with grain boundaries promote an unusually high rate of work hardening in the plastic regime, leading to premature failure. The yield stress follows the Hall-Petch relationship σy~ k/√d, with the slope k increasing with decreasing temperature. At 298K, in addition to dislocation glide and twinning, grain boundary sliding(GBS) becomes significant in samples with grain sizes below 3 μm, considerably enhancing the material's deformability. GBS activation provides an additional recovery mechanism for dislocations accumulating at grain boundaries, facilitating their absorption during sliding and rotation. Analysis of σ Θ relationship suggests that the basal slip is the dominant dislocation mode in mg at 298K. Decreasing grain size suppresses dislocation activity and twinning and increases GBS, resulting in lower Θ and σ Θ values. Suppressing conventional deformation modes coupled with enhanced GBS yields stress softening, breaking down the Hall-Petch relationship in mg below 3 μm grain size, leading to an inverse Hall-Petch behaviour. The work reports new data on the strength, ductility, work hardening and fracture behaviour, and their variations with mg grain size across different temperature regimes.

关键词： Polycrystalline mg mechanical properties Deformation mechanisms Work-hardening Texture evolution Cryogenic temperatures Hall-Petch relationship

Sodium nitroprusside as a signal molecule for up-regulating membrane characteristics,antioxidant defense system to improve flax productivity under water stress

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Oil Crop Science 2024年第3期9卷 160-169页

作者： N.m.Al-Ashkar B.A.Bakry H.m.S.El-Bassiouny m.m.S.Abdallah m.S.Sadak Botany Department Agricultural and Biological Research InstituteNational Research Centre33 El Bohouth Street P.O.12622DokkiGizaEgypt Field Crops Research Department Agricultural and Biological Research InstituteNational Research Centre33 El Bohouth Street P.O.12622DokkiGizaEgypt

Water stress is a critical environmental adversity that significantly impacts the growth,development,and yield of flax *** this study,flax seeds were cultivated under different water irrigation requirements(WIR)(100%,75%,and 50%)to investigate the effects of exogenously supplied nitric oxide(NO)donor sodium nitroprusside(SNP)as foliar treatments at concentrations of 0.0 mmol/L,0.5 mmol/L,1.0 mmol/L,and 2.0 mmol/*** stress led to a significant decrease in plant growth,photosynthetic pigments,yield components such as oil and total carbohydrate *** also resulted in an increase in leaf H2O2 production,lipid peroxidation levels and activities of enzymatic antioxidants including polyphenol oxidase,superoxide dismutase,and nitrate reductase ***,foliar application of SNP improved photosynthetic pigments and antioxidant defense system which mitigated the negative impact of water stress on growth and yield productivity by reducing oxidative damage caused by reactive oxygen species *** use of SNP also decreased H_(2)O_(2) accumulation levels,lipid peroxidation levels,and improved membrane *** treatment at concentration of 2 mmol/L showed superior results compared to other concentrations with extremely significant increases observed in yield characteristics such as oil content,total carbohydrate percentages,and unsaturated fatty acids to saturated fatty acids ratio.

关键词： Flax Fatty acid Sodium nitroprusside Antioxidant enzymes Yield

Solute transport and geochemical modeling of the coastal quaternary aquifer, Delta Dahab Basin, South Sinai, Egypt

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Acta Geochimica 2024年第1期43卷 16-39页

作者： Amira Samy mustafa Eissa Seham Shahen moustafa m.Said Rabab m.Abou-shahaba Division of Water Resources and Arid Land Department of HydrogeochemistryDesert Research CenterCairoEgypt Egypt Desalination Research Center of Excellence Desert Research CenterCairoEgypt Center for Water Supply Studies S&E-Physical&Environmental SciencesTexas A&M University Corpus ChristiCorpus ChristiUSA Department of Chemistry Faculty of Science(Girls)Al-Azhar UniversityYousef Abbas StrNasr CityP.O.Box:11754CairoEgypt

The wadi dahab delta is in a dry, arid coastal zone within Egypt’s south Sinai Peninsula’s eastern portion. The primary water source is the Quaternary coastal alluvial aquifer. The groundwater salinity varies from 890to 8213 mg/L, with a mean value of 3417 mg/L. The dissolved major ions have been used to calculate the seawater mixing index(SWmI) using a linear equation that discriminates the groundwater mostly affected by water–rock interaction(SWmI 1>) and other samples mixed with Seawater(SWmI mposition of groundwater for specifically chosen groundwater samples ranges from-0.645‰ to +5.212‰ for δ^(18)O and from-9.582‰ to + 22.778‰ for δ^(2)H, where the seawater represented by a Red Sea water sample(δ^(18)O + 1.64‰-δ^(2)H + 9.80‰) and reject brine water are considerably enriched the isotopic groundwater values. The geochemical NETPATH model constrained by the dissolved significant ions, isotopes, and the rock aquifer forming minerals as phases indicate the mixing percent with the seawater ranges from 9% to 97% of seawater from 91% to 3% of original recharge water. According to the SEAWAT 3-D flow models, seawater has penetrated the Northeastern Dahab delta aquifer, with the intrusion zone extending1500 m inland. The salt dissolution, upwelling of saline water, recharge from the upstream mountain block, and seawater encroachment are the primary aspects contributing to the deterioration of groundwater quality. These findings may have significance for effective groundwater withdrawal management in arid locations worldwide with similar hydrogeological systems.

关键词： Groundwater geochemistry Seawater intrusion Solute transport SEAWAT

Vaccination effect on a stochastic epidemic model with healing and relapse

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International Journal of Biomathematics 2024年第1期17卷 29-59页

作者： m.m.Abdeslami L.Basri m.El Fatini I.Sekkak R.Taki Laboratory of Partial Differential Equations Spectral Algebra and Geometry Department of mathematics Faculty of Sciences Ibn Tofail UniversityBP 133KénitraMorocco Centre de Recherche en Sante Publique montréal(Québec)H3N 1X9 Canada Departement de Medecine Sociale et Preventive Ecole de SantéPublique de I'Universitéde Montreal 101Avenue du ParcMontréal(Quebec)H3N 1X9Canada EST Sidi Bennour Chouaib Doukkali UniversityEl JadidaMorocco

In this work,we consider a stochastic epidemic model with vaccination,healing and *** prove the existence and the uniqueness of the positive *** establish sufficient conditions for the extinction and the persistence in mean of the stochastic ***,we also establish sufficient conditions for the existence of ergodic stationary distribution to the model,which reveals that the infectious disease will *** graphical illustrations of the approximate solutions of the stochastic epidemic model have been performed.

关键词： Stochastic epidemic model with relapse and healing vaccination extinction persistence in mean markov semigroup stationary distribution

Large magnetocaloric effect and magnetic 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 Hachmi S.El Ouahbi R.moubah Laboratory of Energy and materials Engineering (LGEm) University of Sultan Moulay SlimaneFaculty of Science and Technology (FST) Institute of Applied Physics (IAP)-School of Industrial management (EmINES) Mohammed Ⅵ Polytechnic University National School of Applied Sciences (ENSA) University of Sultan Moulay Slimane Laboratory of mechanics Production and Industrial Engineering (LMPGI)Higher School of Technology of Casablanca (ESTC)University of Hassan Ⅱ Casablanca Laboratory of Radiation on matter and Instrumentation (LRmI) Faculty of Science and Technology (FST) SettatHassan Ⅰ University Laboatory of Physics of Advanced materials and Thermic (LPmAT) Faculty of Science Ain Chock (FSAC)University of Hassan Ⅱ Casablanca

We report on the structural,magnetic,and magnetocaloric 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 mainly in the divalent oxidation state while the Rh ions have+4 ***3powders are found to be antiferromagnetic with a second order magnetic transition at Neel temperature（TN=2.9 K）.Analysis of the magnetic susceptibility versus temperature data in terms of the Curie=Weiss law:(χ=C/（T-θW）) for T>TN,yields θW=-3.1 K and effective magne tic moment ■,which is close to the theoretical value ■.The magnetic entropy change(-ΔSm),was determined by em ploying the thermodynam ic maxwell'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 magnitude of-ΔSmand RCP show that the EuRhO3compound could be a potential candidate to be used in cryogenic magnetic refrigeration.

关键词： Cryogenic magnetic refrigeration magnetic properties magnetocaloric effect Rare earths X-ray photoelectron spectroscopy