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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 EngineeringUniversity of KashanKashan 87317-53153Iran

Curved shells are increasingly utilized in applied engineering due to their shared characteristics with other sandwich structures,flexibility,and attractive ***,the inability of controlling and regulating vibrations and destroying them afterward is a challenge to *** 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 *** core(honeycomb,truss,and corrugated)is analyzed for the bearing of transverse shear *** results show that the honeycomb core has a greater effect on the *** the parameters related to the core and the weight percentage of graphene increase,the frequency *** uniform distribution of graphene platelets results in the lowest natural frequency while the natural frequency ***,without taking into account the piezoelectric layers,the third-order shear deformation theory(TSDT)and fourth-order shear deformation theory(fOSDT)align ***,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： vibration and control doubly curved shell micro-composite honeycomb truss corrugate core

Effect of solidification cooling rate on microstructure and tribology characteristics of Zn-4Si alloy

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 362-373页

作者： f.Akbari M.Golkaram S.Beyrami G.Shirazi k.Mantashloo R.Taghiabadi M.Saghafi Yazdi I.Ansarian Department of Metallurgy and Material Science Imam Khomeini International University(IKIU)Qazvin ***Iran

The main objective of this work was to modify the microstructure and enhance the tribological properties of a new Zn-4Si al-loy through a high solidification cooling rate(SCR).According to the results,by increasing the SCR from 2.0 to 59.5℃/s the average size of primary Si particles and that of the grains reduced from 76.1 and 3780μm to less than about 14.6 and 460μm,***-ing the SCR also enhanced the microstructural homogeneity,decreased the porosity content(by 50%),and increased the matrix hardness(by 36%).These microstructural changes enhanced the tribological *** instance,under the applied pressure of 0.5 MPa,an in-crease in the SCR from 2.0 to 59.5℃/s decreased the wear rate and the average friction coefficient of the alloy by 57%and 23%,*** wear mechanism was also changed from the severe delamination,adhesion,and abrasion in the slowly-cooled alloy to the mild tribolayer delamination/abrasion in the high-cooling-rate-solidified sample.

关键词： zinc-silicon alloy primary silicon solidification cooling rate tribology sliding wear

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

Nickel sulfate solution fluoride separation with hydrous zirconium oxide

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Tungsten 2024年第2期6卷 367-381页

作者： Elbert M.Nigri Ummul k.Sultana André L.A.Santos James W.Vaughan Sonia D.f.Rocha Department of Mining Engineering Federal University of Minas GeraisBelo Horizonte 31270-901Brazil School of Chemical Engineering University of QueenslandSt Lucia 4072Australia

fluoride is an impurity in nickel sulfate production,which is required for electric vehicle *** zirconium oxide(HZO)was evaluated for removing fl uoride from nickel sulfate *** fluoride removal occurred at pH value 4 and optimal pH value is 4–5,considering Zr *** availability decreases with pH due to hydrogen fluoride and zirconium fluoride aqueous *** removal is initially rapid,with 50 wt.%removal in 7 min,followed by slow removal up to 68 wt.%after 72 h and follows second order rate *** removal was dominated by an ion exchange mechanism and resulting Zr–f bonds were observed using fourier-transform infrared *** presence of nickel sulfate decreased loading capacity compared to a salt-free *** maintained adsorption capacity through five cycles of loading and regeneration.

关键词： Hydrous zirconium oxide Nickel sulfate fluoride Adsorption Anion exchange

Monogenic features of urolithiasis: A comprehensive review

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Asian Journal of Urology 2024年第2期11卷 169-179页

作者： kyo Chul koo Abdulghafour Halawani Victor k.f.Wong Dirk Lange Ben H.Chew Department of Urology Yonsei University College of MedicineSeoulRepublic of Korea Department of Urology King Abdulaziz UniversityJeddahSaudi Arabia Department of Urological Sciences University of British ColumbiaStone Centre at Vancouver General HospitalVancouverBritish ColumbiaCanada

Objective: Urolithiasis formation has been attributed to environmental and dietary factors. However, evidence is accumulating that genetic background can contribute to urolithiasis formation. Advancements in the identification of monogenic causes using high-throughput sequencing technologies have shown that urolithiasis has a strong heritable ***: This review describes monogenic factors implicated in a genetic predisposition to urolithiasis. Peer-reviewed journals were evaluated by a PubMed search until July 2023 to summarize disorders associated with monogenic traits, and discuss clinical implications of identification of patients genetically susceptible to urolithiasis ***: Given that more than 80% of urolithiases cases are associated with calcium accumulation, studies have focused mainly on monogenetic contributors to hypercalciuric urolithiases, leading to the identification of receptors, channels, and transporters involved in the regulation of calcium renal tubular reabsorption. Nevertheless, available candidate genes and linkage methods have a low resolution for evaluation of the effects of genetic components versus those of environmental, dietary, and hormonal factors, and genotypes remain undetermined in the majority of urolithiasis ***: The pathophysiology underlying urolithiasis formation is complex and multifactorial, but evidence strongly suggests the existence of numerous monogenic causes of urolithiasis in humans.

关键词： Gene Genetic expression Inheritance pattern Urolithiasis

feeding ecology and interactions with mammal hosts in a symbiotic genus of birds(Buphagus spp.)in Namibia

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Avian Research 2024年第3期15卷 336-344页

作者： Michael S.Lukubwe Daniel Velarde-Garcéz fernando Sequeira Susana Lopes Adrian J.f.k.Craig Vanessa A.Mata Department of Zoology and Entomology Rhodes UniversityMakhandaSouth Africa Department of Wildlife Management and Tourism Studies University of NamibiaKatima Mulilo CampusNamibia Departamento de Biologia Faculdade de CiênciasUniversidade do PortoPortoPortugal CIBIO Centro de Investigação em Biodiversidade e Recursos GenéticosInBIO Laboratório AssociadoCampus de VairãoVairãoPortugal BIOPOLIS Program in Genomics Biodiversity and Land PlanningCIBIOCampus de VairãoVairãoPortugal

As the sole obligate symbiotic birds in Africa,oxpeckers offer a unique model for studying symbiotic *** to the multitrophic level they occupy and the context dependent foraging behavior they exhibit,the type of symbiotic relationship can be *** addition to providing a cleaning service to the host by removing ticks,oxpeckers frequently feed on blood,mucus,and saliva,inflicting potential damage on the ***,we used DNA metabarcoding on faecal samples to analyze the taxonomic composition of the trophic interactions of the Yellow-billed Oxpecker(Buphagus africanus)and Red-billed Oxpecker(***)in northeastern *** contrast to conventional methods,DNA metabarcoding allows for a detailed identification of dietary resources encompassing both mammal hosts and consumed arthropods within the same *** this information,we examined differences in the diet composition between oxpecker species and localities,as well as the co-occurrence between host and arthropod *** findings revealed that oxpeckers predominantly source their diet from mammals,ticks,and flies;however,ticks and flies rarely co-occur in the diet of an *** observed variability among individuals in their feeding ecology,which is strongly correlated with locality and,to a lesser extent,with the mammal *** noted a high degree of mobility between hosts within relatively short periods,with 32%of the samples showing traces of at least two mammal *** study illustrates the dynamic foraging behavior of these specialized symbiotic birds,shedding light on their potential role in pest control services and disease transmission.

关键词： Commensalism Diet DNA metabarcoding Oxpeckers Parasitism Trophic ecology

Macroscopic Traversable Wormholes: Minimum Requirements

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International Journal of Astronomy and Astrophysics 2024年第3期14卷 230-243页

作者： Peter k. f. kuhfittig Department of Mathematics Milwaukee School of Engineering Milwaukee USA

While wormholes are just as good a prediction of Einstein’s theory as black holes, they are subject to severe restrictions from quantum field theory. To allow for the possibility of interstellar travel, a macroscopic wormhole would need to maintain sufficiently low radial tidal forces. It is proposed in this paper that the assumption of zero tidal forces, i.e., the limiting case, is sufficient for overcoming the restrictions from quantum field theory. The feasibility of this approach is subsequently discussed by 1) introducing the additional conditions needed to ensure that the radial tidal forces can indeed be sufficiently low and 2) by viewing traversable wormholes as emergent phenomena, thereby increasing the likelihood of their existence.

关键词： Morris-Thorne Wormholes Traversability Minimum Requirements Stability Compatibility with Quantum field Theory

Thin-Shell Wormholes Admitting Conformal Motions in Spacetimes of Embedding Class One

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International Journal of Astronomy and Astrophysics 2024年第3期14卷 162-171页

作者： Peter k. f. kuhfittig Department of Mathematics Milwaukee School of Engineering Milwaukee USA

This paper discusses the feasibility of thin-shell wormholes in spacetimes of embedding class one admitting a one-parameter group of conformal motions. It is shown that the surface energy density σis positive, while the surface pressure is negative, resulting in , thereby signaling a violation of the null energy condition, a necessary condition for holding a wormhole open. for a Morris-Thorne wormhole, matter that violates the null energy condition is referred to as “exotic”. for the thin-shell wormholes in this paper, however, the violation has a physical explanation since it is a direct consequence of the embedding theory in conjunction with the assumption of conformal symmetry. These properties avoid the need to hypothesize the existence of the highly problematical exotic matter.

关键词： Thin-Shell Wormholes Conformal Symmetry Embedding Class One Exotic Matter

Development of an ultrathin liquid sheet target for laser ion acceleration at high repetition rates in the kilohertz range

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High Power Laser Science and Engineering 2024年第3期12卷 134-145页

作者： M.füle A.P.kovács T.Gilinger M.karnok P.Gaál S.figul G.Marowsky k.Osvay National Laser-Initiated Transmutation Laboratory University of SzegedSzegedHungary Department of Experimental Physics University of SzegedSzegedHungary ELI ALPS ELI-HU Non-Profit Ltd.SzegedHungary Department of Optics and Quantum Electronics University of SzegedSzegedHungary Advanced Microfluidic Systems GmbH GöttingenGermany

A colliding microjet liquid sheet target system was developed and tested for pairs of round nozzles of 10,11 and 18μm in *** sheet's position stability was found to be better than a few *** interaction with 50 mJ laser pulses,the 18μm jet has a resonance amplitude of 16μm at a repetition rate of 33 Hz,while towards 100 Hz it converges to 10μm for all nozzles.A white-light interferometric system was developed to measure the liquid sheet thickness in the target chamber both in air and in vacuum,with a measurement range of 182 nm±1μm and an accuracy of±3%.The overall shape and 3D shape of the sheet follow the Hasson±Peck model in *** vacuum versus air,the sheet gradually loses 10%of its thickness,so the thinnest sheet achieved was below 200 nm at a vacuum level of 10±4mbar,and remained stable for several hours of operation.

关键词： diagnostics laser ion acceleration nanometric liquid sheet targets vacuum test

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