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Applied Mathematics and Mechanics(English Edition) 2024年第10期45卷 1773-1790页

作者： f.SHIRDELAN M.MOHAMMADIMEHR f.BARGOZINI Department of Solid Mechanics Faculty of Mechanical Engineering University of Kashan

curved shells are increasingly utilized in applied engineering due to their shared characteristics with other sandwich structures, flexibility, and attractive appearance. However, the inability of controlling and regulating vibrations and destroying them afterward is a challenge to scientists. In this paper, the curve shell equations and a linear quadratic regulator are adopted for the state feedback design to manage the structure vibrations in state space forms. A five-layer sandwich doubly curved micro-composite shell, comprising two piezoelectric layers for the sensor and actuator, is modeled by the fourth-order shear deformation theory. The core(honeycomb, truss, and corrugated) is analyzed for the bearing of transverse shear forces. The results show that the honeycomb core has a greater effect on the vibrations. When the parameters related to the core and the weight percentage of graphene increase, the frequency increases. The uniform distribution of graphene platelets results in the lowest natural frequency while the natural frequency increases. furthermore, without taking into account the piezoelectric layers,the third-order shear deformation theory(TSDT) and fourth-order shear deformation theory(fOSDT) align closely. However, when the piezoelectric layers are incorporated,these two theories diverge significantly, with the frequencies in the fOSDT being lower than those in the TSDT.

关键词： 74f15 corrugate core doubly curved shell honeycomb micro-composite O343 truss vibration and control

In situ digital testing method for quality assessment of soft soil improvement with polyurethane

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1732-1748页

作者： X.f.Wang c.J.Wang W.V.Yue Z.J.Zhang Z.Q.Yue Department of civil Engineering China University of Geosciences (Beijing)BeijingChina Department of Water Science and Engineering Zhengzhou UniversityZhengzhouChina Department of Geotechnical Engineering Tongji UniversityShanghaiChina Department of civil Engineering The University of Hong KongChina

This study purposes an in situ testing method on quality assessment of soil *** drilling data includes the spatial distribution and in situ strength of untreated and treated soil along three different drillholes measured by on-site drilling monitoring *** factual drilling data can characterize the degree of soil improvement by penetration injection with permeable *** from on-site drilling monitoring shows that the linear zones represent constant drilling speeds shown in the plot of drill bit advancement *** drilling time,which indicates the spatial distributions of soil *** soil profile at the study site is composed of four layers,which includes fill,untreated silty clay,treated silty clay,and mucky *** results of soil profile are verified by the parallel site *** constant drilling speeds profile the coring-resistant strength of drilled *** comparing with the untreated silty clay,the constant drilling speeds of the treated silty clay have been decreased by 13.0-62.8%.Two drilling-speed-based indices of 61.2%and 65.6%are proposed to assess the decreased average drilling speed and the increased in situ strength of treated silty *** tests,*** compressive strength(UcS)test,have been performed with core sample to investigate and characterize in situ strength by comparing that with drilling *** show that the average predicted strengths of treated silty clay are 2.4-6.9 times higher than the average measured strength of untreated silty *** UcS-based indices of 374.5%and 344.2%verified the quality assessment(QA)results by this new in situ *** method provides a cost-effective tool for quality assessment of soil improvement by utilizing the digital drilling data.

关键词： Drilling process monitoring system Hydraulic rotary drilling process constant drilling speed Soil improvement Quality assessment

SARS-coV-2 variants are associated with different clinical courses in children with MIS-c

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World Journal of Pediatrics 2024年第2期20卷 143-152页

作者： Andres f.Moreno Rojas Emelia Bainto Helen Harvey Adriana H.Tremoulet Jane c.Burns Kirsten B.Dummer Department of Pediatrics Division of Pediatric CardiologyUniversity of California San Diegoand Rady Children’s Hospital3020 Children’s Way MC 5004San DiegoCA 92123USA Kawasaki Disease Research center La JollaCAUSA Department of Pediatrics Division of Pediatric Critical CareUniversity of California San Diegoand Rady Children’s HospitalSan DiegoCAUSA Department of Pediatrics University of California San Diegoand Rady Children’s HospitalSan DiegoCAUSA

Background Recent infection with SARS‑coV-2 in children has been associated with multisystem inflammatory syndrome in children(MIS-c).SARS‑coV-2 has undergone different *** publications exist about specific variants and their correlation with the severity of *** This was a single-center,retrospective study including all patients admitted with MIS-c at Rady children’s Hospital-San Diego between May 2020 and March *** epidemiologic data,including viral genomic information,were obtained from public ***,clinical presentation,laboratory values,and outcomes were obtained from electronic medical *** The analysis included 104 pediatric *** MIS-c waves were *** variants in San Diego during the first wave included clades 20A to *** the second wave,there were variants from clades 20A to c,20G,21c(Epsilon),20I(Alpha),and 20J(Gamma).The third wave had Delta strains(clades 21A,21I,and 21J),and the fourth had Omicron variants(clades 21K,21L,and 22c).MIS-c presented with similar symptoms and laboratory findings across all *** patients were admitted to the pediatric intensive care unit(PIcU)(74%)and required inotropic support(63%)during the second *** of the patients required mechanical circulatory support,and only two required invasive ventilatory *** was no *** The various strains of SARS-coV-2 triggered MIS-c with differing severities,with the second wave having a more severe clinical *** the differences in disease severity across variants were due to changes in the virus or other factors remains unknown.

关键词： complications cOVID-19 MIS-c SARS-coV-2 variants

Bolstering integrity in environmental data science and machine learning requires understanding socioecological inequity

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frontiers of Environmental Science & Engineering 2024年第5期18卷 171-179页

作者： Joe f.Bozeman III School of civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA30332USA School of Public Policy Georgia Institute of TechnologyAtlantaGA30332USA

Socioecological inequity in environmental data science—such as inequities deriving from data-driven approaches and machine learning(ML)—are current issues subject to debate and *** is growing consensus around embedding equity throughout all research and design domains—from inception to administration,while also addressing procedural,distributive,and recognitional ***,practically doing so may seem onerous or daunting to *** current perspective helps to alleviate these types of concerns by providing substantiation for the connection between environmental data science and socioecological inequity,using the Systemic Equity framework,and provides the foundation for a paradigmatic shift toward normalizing the use of equity-centered approaches in environmental data science and ML *** the integrity of environmental data science and ML is just beginning from an equity-centered tool development and rigorous application *** this end,this perspective also provides relevant future directions and challenges by overviewing some meaningful tools and strategies—such as applying the Wells-Du Bois Protocol,employing fairness metrics,and systematically addressing irreproducibility;emerging needs and proposals—such as addressing data-proxy bias and supporting convergence research;and establishes a ten-step path ***,the work that environmental scientists and engineers do ultimately affect the well-being of us all.

关键词： Equity Bias Machine Learning Data Science Justice Systemic Equity

Assessment of cO_(2)storage prospect based on physical properties of Rio Bonito formation rock units

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Energy Geoscience 2024年第1期5卷 321-330页

作者： Richardson M.Abraham-A Stephanie San Martín cañas Isabella f.S.Miranda colombo c.G.Tassinari Institute of Energy and Environment(IEE) University of São Paulo(USP)Brazil Research centre for Greenhouse Gas Innovation(RcGI) University of Sãao Paulo(USP)Brazil

The physical properties of the rock units associated with the Rio Bonito formation are presented in this study with the focus on modelling reservoir quality based on petrophysics-derived parameters to evaluate cO_(2)storage *** involves the modelling of the reservoir depths,thicknesses,flow zone indicators(fZI),and effective permeability(Keff)and presenting the cO_(2)storage efficiency factors peculiar to the rock units of the study *** results presented by this study for the stated objectives are not quite common in the *** values range from 200 mD to higher than 2000 mD,and fZI values are generally above 1.0 mm and up to 13.0 mm within the portions covered by the drilled *** sandstone units recorded are up to 20 m thick in some *** Keff and fZI models indicate the sandstone reservoirs as permeable units to support the injection and circulation of cO_(2)within the potential reservoir units of the Rio Bonio formation across São Paulo *** from some points in the southeastern part of the study location,where the Rio Bonito are delineated at depths less than 800 m(minimum cO_(2)storage depth based on best practices),other portions are deeper,ranging from 950 m to 3500 ***-bedded layers will affect the integrity of the rocks as cO_(2)storage tanks or reservoir seals/traps/overburden within the *** bed thicknesses are up to 20 m in some ***,hybrid cO_(2)reservoir units are feasible,especially in portions where thin siltstone layers are sandwiched between sandstone units to provide considerable thicknesses based on cO_(2)storage *** current study shows that useable areas considering reservoir thickness,depth,and other physical qualities will significantly control the cO_(2)storage efficiency of the study *** studies featuring a detailed geophysical exploration of the site to confirm the availability and saturations of preexisting fluid(hydrocarbon and water)are encouraged

关键词： Rio Bonito Effective permeability fluid transmissibility cO_(2)storage prospect Reservoir quality Overburden integrity flow zones

Premature axon-oligodendrocyte interaction contributes to stalling of experimental axon regeneration after injury to the white matter

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Neural Regeneration Research 2024年第3期19卷 469-470页

作者： Ephraim f.Trakhtenberg Department of Neuroscience University of Connecticut School of MedicineFarmingtonCTUSA

Studies from nearly 3 decades ago suggested that,in the central nervous system(cNS),myelination of axons by oligodendrocytes not only helps improve axonal conductivity but also stabilizes circuitry(colello and Schwab,1994).Over the years,myelin sheaths produced by oligodendrocytes have been found to contain multiple molecules that are inhibitory to axonal growth(e.g.,MAG,NogoA,OMgp,Semaphorins)(Yiu and He,2006;Silver et al.,2014).After white matter injury in the adult cNS,myelin debris from damaged axons and dead oligodendrocytes accumulates in the forming glial scar and exposes these myelin-associated axon growth-inhibitory molecules to the injured axonal stumps,thereby contributing to the inhibition of axonal *** development,cNS axons reach their postsynaptic targets and stop growing before oligodendrocytes appear and myelinate them(foran and Peterson,1992;Dangata et al.,1996).Therefore,myelin-associated axon growth-inhibitory molecules interacting with already grown axons during myelination were thought to block axons from promiscuous sprouting and miswiring,thereby stabilizing neural circuitry in the cNS(colello and Schwab,1994).

关键词： thereby white injury

An unexpected cellular fountain of youth:platelets provide factors rejuvenating brain functions

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Signal Transduction and Targeted Therapy 2024年第1期9卷 16-18页

作者： Harald f.Langer Department of cardiology AngiologyHaemostaseology and Medical Intensive CareUniversity Medical Centre MannheimMedical Faculty MannheimHeidelberg UniversityMannheimGermany German centre for cardiovascular Research(DZHK) Partner Site Heidelberg/MannheimMannheimGermany European center for Angioscience Medical Faculty MannheimHeidelberg UniversityMannheimGermany cardiovascular systems biology Medical Clinic IUniversity Heart Center LübeckLübeckGermany

In a recent manuscript published in Nature,Schroer et *** that platelets and in particular platelet derived Pf-4(cXcL4)are a novel factor,which can rejuvenate the mammalian neuronal system.1 These findings have the potential to trigger an entire new field of research opening new platelet-derived candidate effector molecules for supporting regeneration.

关键词： supporting platelets finding

A Preliminary comparative Study on the centering Algorithms for cassiniISS NAc Images

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Research in Astronomy and Astrophysics 2024年第10期24卷 58-65页

作者： T.Liang Q.-f.Zhang G.-M.Liu W.-H.Zhu c.-S.Wang Department of computer Science Jinan UniversityGuangzhou 510632China Sino-french Joint Laboratory for Astrometry Dynamics and Space ScienceJinan UniversityGuangzhou 510632China School of computer Science Guangdong University of EducationGuangzhou 510303China

Obtaining high precision is an important consideration for astrometric studies using images from the Narrow Angle camera(NAc)of the cassini Imaging Science Subsystem(ISS).Selecting the best centering algorithm is key to enhancing astrometric *** this study,we compared the accuracy of five centering algorithms:Gaussian fitting,the modified moments method,and three point-spread function(PSf)fitting methods(effective PSf(ePSf),PSfEx,and extended PSf(x PSf)from the cassini Imaging central Laboratory for Operations(cIcLOPS)).We assessed these algorithms using 70 ISS NAc star field images taken with cL1 and cL2 filters across different stellar *** ePSf method consistently demonstrated the highest accuracy,achieving precision below 0.03 pixels for stars of magnitude *** to the previously considered best,the modified moments method,the e PSf method improved overall accuracy by about 10%and 21%in the sample and line directions,***,the xPSf model provided by cIcLOPS had lower precision than the ***,the ePSf exhibits an improvement in measurement precision of 23%and 17%in the sample and line directions,respectively,over the *** discrepancy might be attributed to the xPSf focusing on photometry rather than *** findings highlight the necessity of constructing PSf models specifically tailored for astrometric purposes in NAc images and provide guidance for enhancing astrometric measurements using these ISS NAc images.

关键词： methods:analytical techniques:image processing stars:imaging astrometry

The viscous strip approach to simplify the calculation of the surface acoustic wave generated streaming

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 711-724页

作者： f.JAZINI DORcHEH M.GHASSEMI fuel cells and Nano Systems(fcNS)Laboratory Department of Mechanical EngineeringK.N.Toosi University of TechnologyTehran 19697Iran

In recent decades,the importance of surface acoustic waves,as a biocompatible tool to integrate with microfluidics,has been proven in various medical and biological *** numerical modeling of acoustic streaming caused by surface acoustic waves in microchannels requires the effect of viscosity to be considered in the equations which complicates the *** this paper,it is shown that the major contribution of viscosity and the horizontal component of actuation is concentrated in a narrow region alongside the actuation *** the inviscid equations are considerably easier to solve,a division into the viscous and inviscid domains would alleviate the computational load *** particles'traces calculated by this approximation are excellently alongside their counterparts from the completely viscous *** is also shown that the optimum thickness for the viscous strip is about 9-fold the acoustic boundary layer thickness for various flow patterns and amplitudes of actuation.

关键词： surface acoustic wave microfluidics numerical simulation particle tracing acoustic streaming

Langmuir-Schaefer film Investigation and Density functional Theory Band Gap calculations of calix[n]arene-Para-Aminobenzoic Acid for Drug Nanosensor Application

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1311-1318页

作者： WONG Yeong Yi f L Supian A Radzwan M Musa N f N Abd Karim Department of Physics Sultan Idris Education UniversityTanjong Malim 35900Malaysia Department of chemistry Sultan Idris Education UniversityTanjong Malim 35900Malaysia

calix[n]arenes was utilized to detect PABA,the primary sunscreen *** study investigates the interaction of calix[4]arene(c4),calix[6]arene(c6),and PABA using the Langmuir method and first-principle density functional theory(DfT).Using the Langmuir-Schaefer(LS)technique,an ultrathin film composed of calix[n]arenes and their complexes with PABA was deposited on various *** on the Langmuir study,the PABA molecule was bonded to the lower rims of both c4 and c6 with the host-guest ratio of 1:*** of the LS films formed were then characterized by ultravioletvisible spectroscopy(UV-Vis),fourier-transform infrared spectroscopy(fTIR)and carbon,hydrogen,nitrogen,sulfur elemental analyzer(cHNS).The band gap reduction obtained in the DfT study denotes the charge transfer interaction with promising reactivity between the calix[n]arenes and *** sensing of PABA by c4 and c6 is successful based on the formation of bonding between them due to the hosts’effective trapping *** outcomes of this study could be applied to drug delivery systems for future pharmaceutical and medical applications.

关键词： calix[n]arenes band gap density functional theory Langmuir-Schaefer PABA sensor