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journal of Magnesium and Alloys 2024年第1期12卷 394-404页

作者： Lokesh Choudhary Parama Chakraborty Banerjee r.K.Singh raman Derrek E.Lobo Christopher D.Easton Mainak Majumder Frank Witte jörg F.Löffler Department of Mechanical and Aerospace Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Department of Chemical and Biological Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Nanoscale Science and Engineering Laboratory(NSEL) Bldg 37Monash UniversityClayton CampusMelbourneVIC 3800Australia CSIrO Materials Science and Engineering Bayview AvenueClaytonVIC 3168Australia julius Wolff Institute and Berlin Brandenburg Center for regenerative Therapies Charité–Universitätsmedizin BerlinAugustenburger Platz 113353 BerlinGermany Laboratory of Metal Physics and Technology Department of MaterialsETH Zurich8093 ZurichSwitzerland

Biodegradable implants are critical for regenerative orthopaedic procedures,but they may suffer from too fast corrosion in human-body *** necessitates the synthesis of a suitable coating that may improve the corrosion resistance of these implants without compromising their mechanical *** this study,an AZ91 magnesium alloy,as a representative for a biodegradable Mg implant material,was modified with a thin reduced graphene oxide(rGO)-calcium carbonate(CaCO_(3))composite *** analytical and in-vitro electrochemical characterization reveals that this coating significantly improves the corrosion resistance and mechanical integrity,and thus has the potential to greatly extend the related application field.

关键词： Graphene coating Biodegradable implant Hydroxyapatite Corrosion Magnesium alloy

Lax-Oleinik-Type Formulas and Efficient Algorithms for Certain High-Dimensional Optimal Control Problems

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1428-1471页

作者： Paula Chen jerome Darbon Tingwei Meng Division of Applied Mathematics Brown UniversityProvidenceRIUSA Department of Mathematics UCLALos AngelesCAUSA

Two of the main challenges in optimal control are solving problems with state-dependent running costs and developing efficient numerical solvers that are computationally tractable in high *** this paper,we provide analytical solutions to certain optimal control problems whose running cost depends on the state variable and with constraints on the *** also provide Lax-Oleinik-type representation formulas for the corresponding Hamilton-jacobi partial differential equations with state-dependent ***,we present an efficient,grid-free numerical solver based on our representation formulas,which is shown to scale linearly with the state dimension,and thus,to overcome the curse of *** existing optimization methods and the min-plus technique,we extend our numerical solvers to address more general classes of convex and nonconvex initial *** demonstrate the capabilities of our numerical solvers using implementations on a central processing unit(CPU)and a field-programmable gate array(FPGA).In several cases,our FPGA implementation obtains over a 10 times speedup compared to the CPU,which demonstrates the promising performance boosts FPGAs can *** numerical results show that our solvers have the potential to serve as a building block for solving broader classes of high-dimensional optimal control problems in real-time.

关键词： Optimal control Hamilton-jacobi partial differential equations Grid-free numerical methods High dimensions Field-programmable gate arrays(FPGAs)

Analysis of ancient mass extinction recoveries in marine environments: generating strategies for managing outcomes of the current mass extinction

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National Science review 2024年第1期11卷 8-10页

作者： David j.Bottjer Department of Earth Sciences University of Southern California

The defining feature of a mass extinction and its associated recovery is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story, as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosystems and environments, and hence geographic areas [1].

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Global weirding at mass extinction horizons

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National Science review 2024年第1期11卷 10-12页

作者： Gregory j.retallack Department of Earth Sciences University of Oregon

A strong motivation for studying mass extinctions is understanding how current climatic and biodiversity crises will affect creatures living on land such as ourselves. Perhaps the question is: how bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible worst-case scenario [1].

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Changes in snow cover extent in the Central Taurus Mountains from 1981 to 2021 in relation to temperature, precipitation, and atmospheric teleconnections

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journal of Mountain Science 2024年第1期21卷 49-67页

作者： Ecmel ErLAT Fulya AYDIN-KANDEMİr Department of Geography Ege UniversityIzmir 35100Türkiye Climate Change and Zero Waste Department Antalya Metropolitan MunicipalityAntalya 07310Türkiye Hydropolitics Association Ankara 06680Türkiye

The snow cover over the Taurus Mountains affects water supply, agriculture, and hydropower generation in the region. In this study, we analyzed the monthly Snow Cover Extent(SCE) from November to April in the Central Taurus Mountains(Bolkar, Aladaglar, Tahtali and Binboga Mountains) from 1981 to 2021. Linear trends of snow cover season(November to April) over the last 41 years showed decreases in SCE primarily at lower elevations. The downward trend in SCE was found to be more pronounced and statistically significant for only November and March. SCE in the Central Taurus Mountains has declined about-6.3% per decade for 2500-3000 m in November and about-6.0% per decade for 1000-1500 m and 3000+ m in March over the last 41 years. The loss of SCE has become evident since the 2000s, and the lowest negative anomalies in SCE have been observed in 2014, 2001, and 2007 in the last 41 years, which are consistent with an increase in air temperature and decreased precipitation. SCE was correlated with both mean temperature and precipitation, with temperature having a greater relative importance at all elevated gradients. results showed that there is a strong linear relationship between SCE and the mean air temperature(r =-0.80) and precipitation(r = 0.44) for all elevated gradients during the snow season. The Arctic Oscillation(AO), the North Atlantic Oscillation(NAO), and the Mediterranean Oscillation(MO) winter indices were used to explain the year-to-year variability in SCE over the Central Taurus Mountains. The results showed that the inter-annual variability observed in the winter SCE on the Central Taurus Mountains was positively correlated with the phases of the winter AO, NAO and MO, especially below 2000 m elevation.

关键词： Snow cover extent Atmospheric teleconnection Central Taurus Mountains Air temperature and precipitation Geographic Information Systems Türkiye

Neurogenic potential of NG2 in neurotrauma:a systematic review

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Neural regeneration research 2024年第12期19卷 2673-2683页

作者： Yuri r.rigo radharani Benvenutti Luis V.Portela Nathan r.Strogulski Departamento de Bioquímica Instituto de Ciências Básicas da SaúdeUniversidade Federal do Rio Grande do Sul(UFRGS)Porto AlegreBrazil School of Pharmacy and Biomolecular Sciences RCSI University of Medicine and Health SciencesDublinIreland School of Biochemistry and Immunology Trinity Biomedical Sciences InstituteTrinity College DublinUniversity of DublinDublinIreland

regenerative approaches towards neuronal loss following traumatic brain or spinal cord injury have long been considered a dogma in neuroscience and remain a cutting-edge area of *** is reflected in a large disparity between the number of studies investigating primary and secondary injury as therapeutic to rgets in spinal co rd and traumatic brain *** advances in biotechnology may have the potential to reshape the current state-of-the-art and bring focus to primary injury neurotrauma *** studies using neural-glial factor/antigen 2(NG2)cells indicate that they may differentiate into neurons even in the developed *** these cells show great potential to play a regenerative role,studies have been conducted to test various manipulations in neurotrauma models aimed at eliciting a neurogenic response from *** the present study,we systematically reviewed the experimental protocols and findings described in the scientific literature,which were peer-reviewed original research articles(1)describing preclinical experimental studies,(2)investigating NG2 cells,(3)associated with neurogenesis and neurotrauma,and(4)in vitro and/or in vivo,available in PubMed/MEDLINE,Web of Science or SCOPUS,from 1998 to ***,we have reviewed a total of 1504 papers,and summarized findings that ultimately suggest that NG2 cells possess an inducible neurogenic potential in animal models and in *** also discriminate findings of NG2 neurogenesis promoted by different pharmacological and genetic approaches over functional and biochemical outcomes of traumatic brain injury and spinal co rd injury models,and provide mounting evidence for the potential benefits of manipulated NG2 cell ex vivo transplantation in primary injury *** findings indicate the feasibility of NG2 cell neurogenesis strategies and add new players in the development of therapeutic alternatives for neurotrauma.

关键词： neural-glial antigen 2 neural-glial factor 2 neuron differentiation NG2 cell regeneration spinal cord injury(SCI) traumatic brain injury(TBI)

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

Nonstationary laser-supported ionization wave in layer of porous substance with subcritical density

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Matter and radiation at Extremes 2024年第1期9卷 58-70页

作者： S.Yu Gus’kov r.A.Yakhin P.N.Lebedev Physical Institute of russian Academy of Sciences Leninskii Prospect 53Moscow 119991Russia

A time-dependent analytical solution is found for the velocity of a plane ionization wave generated under nanosecond laser pulse action on the surface of a flat layer of low-Z porous substance with density less than the critical density of the produced *** corrections for the two-dimensional nature of the problem when a laser beam of finite radius interacts with a flat target,this solution is in quantitative agreement with measurements of ionization wave velocity in various *** solution compared with experimental data covering wide ranges of performance conditions,namely,(3-8)×10^(14)W cm^(−2)for laser pulse intensity,0.3-3 ns for pulse duration,0.35-0.53μm for laser wavelength,100-1000μm for laser beam radius,380-950μm for layer thickness,4.5-12 mg cm^(−3)for average density of porous substance,and 1-25μm for average pore *** parameters of the laser beam that ensure the generation of a plane ionization wave in a layer of subcritical porous matter are determined for the problem statements and are found to meet the requirements of practical applications.

关键词： laser pulse porous

Metabolic reprogramming by Syntenin-1 directs rA FLS and endothelial cell-mediated inflammation and angiogenesis

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Cellular & Molecular Immunology 2024年第1期21卷 33-46页

作者： Anja Meyer Stephanie r.Zack Wes Nijim Adel Burgos Vishwa Patel Brian Zanotti Michael V.Volin M.Asif Amin Myles j.Lewis Costantino Pitzalis Shiva Arami joseph A.Karam Nadera j.Sweiss Shiva Shahrara jesse Brown VA Medical Center ChicagoILUSA Department of Medicine Division of RheumatologyThe University of Illinois at ChicagoChicagoILUSA Department of Microbiology and Immunology Midwestern UniversityDowners GroveILUSA Division of rheumatology and Clinical Autoimmunity Center of Excellence University of MichiganAnn ArborMIUSA Centre for Experimental Medicine and rheumatology William Harvey Research InstituteBarts and The London School of Medicine and DentistryQueen Mary University of LondonLondonUnited Kingdom Centre for Experimental Medicine&rheumatology William Harvey Research InstituteQueen Mary University of London and Barts NIHR BRC&NHS TrustLondonUK Department of Biomedical Sciences Humanitas Universityand Humanitas Research HospitalMilanItaly Department of Orthopedic Surgery the University of Illinois at ChicagoChicagoILUSA

A novel rheumatoid arthritis(rA)synovial fluid protein,Syntenin-1,and its receptor,Syndecan-1(SDC-1),are colocalized on rA synovial tissue endothelial cells and fibroblast-like synoviocytes(FLS).Syntenin-1 exacerbates the inflammatory landscape of endothelial cells and rA FLS by upregulating transcription of IrF1/5/7/9,IL-1β,IL-6,and CCL2 through SDC-1 ligation and HIF1α,or mTOr ***,Syntenin-1 orchestrates rA FLS and endothelial cell invasion via SDC-1 and/or mTOr *** Syntenin-1 reprogrammed endothelial cells,the dynamic expression of metabolic intermediates coincides with escalated glycolysis along with unchanged oxidative factors,AMPK,PGC-1α,citrate,and inactive oxidative ***,rA FLS rewired by Syntenin-1 displayed a modest glycolytic-ATP accompanied by a robust mitochondrial-ATP *** enriched mitochondrial-ATP detected in Syntenin-1 reprogrammed rA FLS was coupled with mitochondrial fusion and fission recapitulated by escalated Mitofusin-2 and DrP1 *** found that VEGFr1/2 and Notch1 networks are responsible for the crosstalk between Syntenin-1 rewired endothelial cells and rA FLS,which are also represented in rA *** to rA explants,morphological and transcriptome studies authenticated the importance of VEGFr1/2,Notch1,rAPTOr,and HIF1αpathways in Syntenin-1 arthritic mice and their obstruction in SDC-1 deficient ***,dysregulation of SDC-1,mTOr,and HIF1αnegated Syntenin-1 inflammatory phenotype in rA explants,while inhibition of HIF1αimpaired synovial angiogenic imprint amplified by *** conclusion,since the current therapies are ineffective on Syntenin-1 and SDC-1 expression in rA synovial tissue and blood,targeting this pathway and its interconnected metabolic intermediates may provide a novel therapeutic strategy.

关键词： Syntenin-1 Syndecan-1 rA FLS rA explants immunometabolism

Nonlinear dynamic modeling of planar moving Timoshenko beam considering non-rigid non-elastic axial effects

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 479-496页

作者： M.ABBASI GAVArI M.r.HOMAEINEZHAD Faculty of Mechanical Engineering K.N.Toosi University of TechnologyTehran 19991-43344Iran

Due to the importance of vibration effects on the functional accuracy of mechanical systems,this research aims to develop a precise model of a nonlinearly vibrating single-link mobile flexible *** manipulator consists of an elastic arm,a rotary motor,and a rigid carrier,and undergoes general in-plane rigid body motion along with elastic transverse *** accurately model the elastic behavior,Timoshenko’s beam theory is used to describe the flexible arm,which accounts for rotary inertia and shear deformation *** applying Newton’s second law,the nonlinear governing equations of motion for the manipulator are derived as a coupled system of ordinary differential equations(ODEs)and partial differential equations(PDEs).Then,the assumed mode method(AMM)is used to solve this nonlinear system of governing equations with appropriate shape *** assumed modes can be obtained after solving the characteristic equation of a Timoshenko beam with clamped boundary conditions at one end and an attached mass/inertia at the *** addition,the effect of the transverse vibration of the inextensible arm on its axial behavior is *** the axial rigidity,the effect makes the rigid body dynamics invalid for the axial behavior of the ***,numerical simulations are conducted to evaluate the performance of the developed model,and the results are compared with those obtained by the finite element *** comparison confirms the validity of the proposed dynamic model for the *** to the mentioned features,this model can be reliable for investigating the system’s vibrational behavior and implementing vibration control algorithms.

关键词： planar moving Timoshenko beam non-rigid non-elastic axial effect as-sumed mode method(AMM) nonlinear motion analysis