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Wave propagation of a functionally graded plate via integral variables with a hyperbolic arcsine function

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 547-561页

作者： mokhtar Ellali mokhtar Bouazza Ashraf m.Zenkour Smart structures Laboratory University of Ain TemouchentAin Temouchent 46000Algeria Department of Civil Engineering University Tahri Mohamed of BecharBechar 08000Algeria Department of mathematics Faculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia Laboratory of materials and Hydrology(LmH) University of Sidi Bel AbbesSidi Bel Abbes 22000Algeria Department of mathematics Faculty of ScienceKafrelsheikh UniversityKafrelsheikh 33516Egypt

Several studies on functionally graded materials(FGms)have been done by researchers,but few studies have dealt with the impact of the modification of the properties of materials with regard to the functional propagation of the waves in *** work aims to explore the effects of changing compositional characteristics and the volume fraction of the constituent of plate materials regarding the wave propagation response of thick plates of *** model is based on a higher-order theory and a new displacement field with four unknowns that introduce indeterminate integral variables with a hyperbolic arcsine *** FGm plate is assumed to consist of a mixture of metal and ceramic,and its properties change depending on the power functions of the thickness of the plate,such as linear,quadratic,cubic,and inverse *** utilizing Hamilton’s principle,general formulae of the wave propagation were obtained to establish wave modes and phase velocity curves of the wave propagation in a functionally graded plate,including the effects of changing compositional characteristics of materials.

关键词： FGm plate effects of material properties wave propagation indeterminate integral variables inverse sinus hyperbolic function

Parametric investigation on the novel and cost-effective nano fly ash impregnated geopolymer system for sustainable construction

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Frontiers of Structural and Civil Engineering 2024年第2期18卷 170-183页

作者： R.mOHANA S.m.Leela BHARATHI Department of Civil Engineering Mepco Schlenk Engineering CollegeSivakasi 626123India

The hazardous environmental effects of greenhouse gas emissions and climate change demand alternative sources for cementitious materials in the construction *** development of geopolymer structures provides a way of producing 100%cement-free *** this research work,a novel and simple way of deriving nano particles from waste fly ash particles is *** effect of adding the synthesized nano fly ash particles as a filler medium in geopolymer mortars was investigated by considering strength and durability *** optimization was done by using regression analysis on the geopolymer mortar and the impact of adding nano fly ash particles was studied by varying different percentages of addition ranging from 0 to 7.5%by weight of binder *** the results,it was observed that 1%nano fly ash acted not only as a filler but also as nano-sized precursors of the polymerization process,resulting in denser geopolymer *** can explain the extraordinary gain in strength of 72.11 mPa as well as the denser core with negligible level of chloride ion penetration,making the material suitable for the development of structures susceptible to marine environment.

关键词： geopolymer nano fly ash chloride ion penetration durability polymerization fillers

Viscoelastic potential flow instability theory of Rivlin-Ericksen electrified fluids of cylindrical interface

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Journal of Ocean Engineering and Science 2024年第4期9卷 311-316页

作者： D.m.mostafa Department of mathematics College of ScienceQassim UniversityPO Box 6644Buraidah 51452Saudi Arabia Department of mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

A linear electrohydrodynamic Kelvin-Helmholtz instability of the interface between two viscoelastic Rivlin-Ericksen fluids enclosed by two concentric horizontal cylinders has been studied via the viscoelastic potential flow *** dispersion equation of complex coefficients for asymmetric disturbance has been obtained by using normal mode *** stability criteria are analyzed theoretically and illustrated *** imaginary part of growth rate is plotted versus the wave *** influences of dynamic viscoelastic,uniform velocities,Reynolds number,electric field,dynamic viscosity,density fluids ratio,dielectric constant ratio and inner fluid fraction on the stability of the system are *** study finds its significance in Ocean pipelines to transfer oil or gas such as Eastern Siberia-Pacific Ocean oil pipeline.

关键词： Rivlin-Ericksen fluid Cylindrical flow Viscoelastic potential flow Electrohydrodynamics stability

managing stress granule disassembly with ubiquitin and its cousin

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Signal Transduction and Targeted Therapy 2021年第12期6卷 3377-3378页

作者： Stefan müller Institute of Biochemistry II Gustav Embden ZentrumGoethe University FrankfurtFaculty of MedicineFrankfurtGermany

Recently,maxwell et al.1 revealed a critical function of ubiquitylation in stress granule(SG)disassembly upon recovery from heat *** are continuously exposed to endogenous or environmental *** stress endangers DNA integrity,whereas proteotoxic stress causes an imbalance in protein homeostasis(proteostasis).Genotoxic insults activate DNA damage response pathways that halt the cell-cycle progression and initiate DNA *** quality control(PQC)systems in turn safeguard the integrity of the proteome and prepare for the restart of cellular activities upon stress *** genome and proteome integrity pathways are orchestrated by ubiquitin signaling and the ubiquitin-proteasome system(UPS).

关键词： stress aging integrity

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

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