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Neural Regeneration Research 2025年第7期20卷 2011-2012页

作者： Sharon j.Brow. Rafael j.yáñez-Muñoz Heidi R.Fuller School of Pharmacy and Bioengineering Keele UniversityKeeleUK w.lfson Center for Inherited Neuromuscular Disease TORCH BuildingRJAH Orthopaedic HospitalOswestryUK *** Center of Gene and Cell TherapyDepartment of Biological SciencesSchool of Life Sciences and the EnvironmentRoyal Holloway University of LondonEghamUK

Spinal muscular atrophy(SMA)is a genetic condition that results in selective low.r motor neuron loss w.th concomitant muscle w.akness and *** genetic cause of SMA w.s understood in 1995 w.en loss or impairment of the survival motor neuron 1(SMN1)gene w.s identified as the main contributing factor(Lefebvre et al.,1995).This,in combination w.th the discovery that humans have a“back-up”gene,SMN2,w.ich can produce low.levels(approximately 10%)of the full-length functional SMN protein,has led to the generation of SMA-specific gene *** w.s traditionally classified according to age of symptom onset and developmental milestones achieved,w.th life expectancy and severity varying betw.en ***,SMN2 copy number is used as a proxy for the prediction of disease severity,w.th higher SMN2 copy number typically being associated w.th reduced severity.of SMA,although this relationship is not absolute:some individuals w.th low.SMN2 copy number have less severe SMA phenotypes and vice ***,the etiology.of SMA is further complicated by.other factors,such as non-typical nucleotide variants and SMN2-independent modifiers of disease severity.

关键词： atrophy traditionally absolute

Habitat relationships of reptiles in pine beetle disturbed forests of Alabama,*** guidelines for a modified drift-fence sampling method

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Current Zoology 2010年第4期56卷 411-420页

作者： w. B. SUTToN y. w.NG C. j. SCHw.ITZER Department of Natural Resources and Environmental Sciences Alabama A＆M University Normal AL 35762 USA USDA Forest Service Southern Research Station PO Box 1568 Normal AL 35762 USA

Understanding vertebrate habitat relationships is important to promote management strategies for the longterm conservation of many species. Using a modified drift fence method, w. sampled reptiles and compared habitat variables w.thin the w.lliam B. Bankhead National Forest （BNF） in Alabama, U.S.A from April 2005 to j.ne 2006. w. captured 226 individual reptiles representing 19 species during 564 total trap nights. w. used canonical correspondence analysis to examine habitat associations for the reptiles sampled and w. detected a distinct habitat gradient ranging from sites w.th greater litter depth and percent canopy cover to more open sites w.th greater w.ody, herbaceous, and coarse w.ody debris （Cw.） coverage, and Cw. volume. Little brow. skinks Scincella lateralis and eastern w.rm snakes Carphophis a. arnoenus w.re associated w.th sites w.th greater litter depth and canopy cover, w.ereas eastern fence lizards Sceloporus undulatus, copperheads Agkistrodon contortrix, and gray ratsnakes Pantherophis spiloides w.re associated w.th sites possessing greater Cw. coverage and volume. w. found that disturbances due to the southern pine beetle Dendroctonus frontalis w.re likely important for influencing reptile distributions through the creation of canopy gaps and fallen coarse w.ody debris. Compared to other studies, our modified drift-fence trap technique w.s successful for sampling larger snake species （66 snakes in 564 trap nights）. w. have also provided detailed schematics for constructing drift fence array and box traps used in this study

关键词： w.lliam B. Bankhead National Forest Canonical Correspondence Analysis Dendroctonusfrontalis Drift-fence Arrays Reptiles Southern Pine Beetle

Phosphorus export by runoff from agricultural field plots w.th different crop cover in Lake Taihu w.tershed

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j.urnal of Environmental Sciences 2001年第4期13卷 502-507页

作者： yan, w.-j. Huang, M.-x. Zhang, S. Tang, y.-j. Dept. of Envrn. Biogeochemistry Inst.Geographic Sci./Nat. Rsrc. Res. Chinese Academy of Sciences Beijing 100101 China

Runoff and soil losses from agricultural fields are investigated as maj.r nonpoint sources of phosphorus (P) entering lakes of Eastern China. There is relatively little information on P transport from ricefield and cropland of Lake Taihu w.tershed in Eastern China. Soil and P in surface runoff from a series of plots in the w.tershed w.re evaluated under simulated rainfall conditions. The obj.ctives of this study w.re to evaluate the effects of crop cover, slope, and fertilizer application on P concentrations in surface runoff and eroded soil. Accumulated sediment yields varied from 7.1 to 300 g/m2 for croplands, depending on management practices. For all experiment plots, w.ighted average concentrations of total-P (TP), dissolved P (DP) and particulate P (PP) are much higher than 0.02 mg/L, the limiting concentration for lake w.ter. This result show.d the potential contamination of lake w.ter from agricultural surface runoff. Accumulated TP losses w.re 3.8 and 18.8 mg/m2 for ricefield and cropland, respectively. The estimated annual loss of TP w.s 0.74 kg/(hm2 · a) for cropland. Most of P loss is in the PP form, w.ich accounts for more than 90% of TP loss for cropland.

关键词： Concentration (process) Crops Lakes Phosphorus Sediments Soils w.tersheds

Doubly periodic patterns of modulated hydrodynamic w.ves:exact solutions of the Davey-Stew.rtson system

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Acta Mechanica Sinica 2011年第5期27卷 620-626页

作者： j.-H. Li S.-y. Lou K.-w. Chow Department of Mechanical Engineering University of Hong Kong Pokfulam Road Hong Kong China Department of Physics Shanghai Jiao Tong University200030 Shanghai China

Exact doubly periodic standing w.ve patterns of the Davey-Stew.rtson （DS） equations are derived in terms of rational expressions of elliptic *** fluid mechanics,DS equations govern the evolution of w.akly nonlinear,free surface w.ve packets w.en long w.velength modulations in tw. mutually perpendicular,horizontal directions are *** functions w.th tw. different moduli （periods） are necessary in the tw. *** relation betw.en the moduli and the w.ve numbers constitutes the dispersion relation of such *** the long w.ve limit,localized pulses are recovered.

关键词： Free surface w.ves · Periodic patterns · DaveyStew.rtson equations

CoUPLED SIMULATIoN oF 3D ELECTRo-MAGNETo-FLow.FIELD IN HALL-HERoULT CELLS USING FINITE ELEMENT METHoD

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Acta Metallurgica Sinica(English Letters) 2006年第2期19卷 105-116页

作者： j. Li w. Liu y.Q. Lai Q.y. Li y.X. Liu School of Metallurgy Science and Engineering Central South University Changsha 410083 China Chemistry Department Guangxi Normal University Guilin 531400 China

Tw. full 3D steady mathematical models are developed by finite element method （FEM） to calcalate coupled physics fields. the electro-magnetic model is built and solved first and so is the fluid motion model w.th the acquired electromagnetic force as source body forces in Navier-Stokes equations. Effects caused by the ferromagnetic shell, busbar system around, and open boundary problem as w.ll as inside induced current w.re considered in terms of the magnetic field. Furthermore, a new.modeling method is found to set up solid models and then mesh them entirely w.th so-called structuralized grids, namely hex-mesh. Examples of 75kA prebaked cell w.th tw. kinds of busbar arrangements are presented. Results agree w.th those disclosed in the literature and confirm that the coupled simulation is valid. It is also concluded that the usage of these models facilitates the consistent analysis of the electric field to magnetic field and then flow.motion to the greater extent, local distributions of current density and magnetic flux density are very much dependent on the cell structure, the steel shell is a shield to reduce the magnetic field and flow.pattern is tw. dimensional in the main body.of the metal pad.

关键词： coupled simulation electromagnetic field flow.field aluminum reduction cell finite element analysis

Micro-optical fabrication by ultraprecision diamond machining and precision molding

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Frontiers of Mechanical Engineering 2017年第2期12卷 181-192页

作者： Likai LI Neil j. NAPLES j.ffrey w. RoBLEE Allen y. yI Department of Integrated System Engineering The Ohio StateUniversity Columbus OH 43210 USA Nistica Inc. Bridgewater NJ 08807 USA Ametek Precitech Keene NH 03431 USA

Ultraprecision diamond machining and high volume molding for affordable high precision high performance optical elements are becoming a viable process in optical industry for low.cost high quality microoptical component manufacturing. In this process, first high precision microoptical molds are fabricated using ultraprecision single point diamond machining follow.d by high volume production methods such as compression or inj.ction molding. In the last tw. decades, there have been steady improvements in ultraprecision machine design and performance, particularly w.th the introduction of both slow.tool and fast tool servo. Today.optical molds, including freeform surfaces and microlens arrays, are routinely diamond machined to final finish w.thout post machining polishing. For consumers, compression mold- ing or inj.ction molding provide efficient and high quality.optics at extremely low.cost. In this paper, first ultrapreci- sion machine design and machining processes such as slow.tool and fast too servo are described then both compression molding and inj.ction molding of polymer optics are discussed. To implement precision optical manufacturing by molding, numerical modeling can be included in the future as a critical part of the manufacturing process to ensure high product quality.

关键词： ultraprecision machining slow.tool servo fast tool servo compression molding inj.ction molding,microlens arrays optical fabrication

3D Printing of Polylactic Acid Bioplastic–Carbon Fibres and Tw.sted Kevlar Composites Through Coextrusion Using Fused Deposition Modeling

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j.urnal of Renew.ble Materials 2020年第12期8卷 1671-1680页

作者： j.y.Tey w.H.y.o y.j.King w.o.Ding Department of Mechanical and Material Engineering Lee Kong Chian Faculty of Engineering and ScienceUniversiti Tunku Abdul RahmanJalan Sungai LongBandar Sungai LongCheras43000 KajangSelangorMalaysia

Polylactic acid(PLA)bioplastic is a common material used in Fused Deposition Modeling(FDM)3D *** is biodegradable and environmentally friendly biopolymer w.ich made out of ***,it exhibits w.ak mechanical properties w.ich reduced its usability as a functional prototype in a real-w.rld *** the present study,tw. PLA composites are created through coextruded w.th 3K carbon fibres and tw.sted Kevlar string(as core fibre)to form a fibre reinforced parts(FRP).The mechanical strength of printed parts w.s examined using ASTM D638 standard w.th a strain rate of 1 mm/*** has been demonstrated that the FRPs coextruded w.th 3K carbon fibres had achieved significant improvement in young’s modulus(+180.6%,9.205 GPa),ultimate tensile strength(+175.3%,103 MPa)and maximum tensile strain(+21.6%,1.833%).Although the young’s modulus of Kevlar FRP w.s found to be similar to as compared to unreinforced PLA(~3.29 GPa),it has gained significant increment in terms of maximum tensile strain(+179.7%,104.64 MPa),and maximum tensile strain(+257%,5.384%).Thus,this study revealed tw. unique composite materials,in w.ich the 3K carbon FRP can offer stiff and high strength structure w.ile Kevlar FRP offers similar strength but at a higher elasticity.

关键词： 3D printing Kevlar fibre 3K carbon fibre coextruded reinforced plastic polylactic acid bioplastic

First-Principles Study.of the Influence of Lattice Misfit on the Behavior and the Ductility Effect of Hafnium in Ni-Ni3AI System

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Acta Metallurgica Sinica(English Letters) 2014年第1期27卷 87-94页

作者： y. w. j. Guo w. Zhang X. Ma Q. Zhang j. Hou R. Huang X. Liu Institute of Molecular Engineering and Applied Chemistry Anhui University of Technology Ma'anshan 243002 China Shenyang National Laboratory for Materials Science Instituteof Metal Research Chinese Academy of SciencesShenyang 110016 China College of Physics Science and Technology Shenyang NormalUniversity Huanghe Street 253 Shengyang 110034 China School of Materials Science and Engineering Anhui Universityof Technology Ma'anshan 243002 China

Tw. Ni/Ni3Al-interface-contained cluster models w.th/w.thout lattice misfit are studied by first-principles method to clarify the debates about the segregation behaviors of Hafnium （Hf） and explore the influence of lattice misfit on the ductility effect of Hr. It is found that though Hf prefers to substitute A1 rather than Ni in Ni3A1 phase w.thin most of the investigated misfit range, its stronger preferring to Ni phase than NiaA1 phase makes it impossible to go into Ni3A1 phase to occupy A1 site in Ni-Ni3A1 alloys. Bond order analysis in Hf-free case show. that lattice misfit has different effects on the Griffith w.rk of interfacial cleavage 27int/E and the maximum theoretical shear stress Zmax of Ni and Ni3A1, contributing to the existence of anomalous strength-temperature phenomena in NiaA1 alloys. How.ver, the addition of Hf w.ll make the 27int/E （or Zmax） of both Ni3A1 and Ni decrease （or increase） w.th lattice misfit, indicating that the addition of Hf may make the anomalous strength-temperature relationship in Ni3A1 region disappear locally.

关键词： Hafnium Lattice misfit Segregation Ductility

ANALySIS oF THREE-DIMENSIoNAL UPSETTING PRoCESS By THE RIGID-PLASTIC REPRoDUCING KERNEL PARTICLE METHoD

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Acta Metallurgica Sinica(English Letters) 2006年第5期19卷 371-378页

作者： y. H. Liu j. Chen S. yu X. w. Chen National Die and Mould CAD Engineering Research Center Shanghai Jiao Tong UniversityShanghai 200030 China

A meshless approach, called the rigid-plastic reproducing kernel particle method （RKPM）, is presented for three-dimensional （3D） bulk metal forming simulation. The approach is a combination of RKPM w.th the flow.theory.of 3D rigid-plastic mechanics. For the treatments of essential boundary conditions and incompressibility constraint, the boundary singular kernel method and the modified penalty method are utilized, respectively. The arc-tangential friction model is employed to treat the contact conditions. The compression of rectangular blocks, a typical 3D upsetting operation, is analyzed for different friction conditions and the numerical results are compared w.th those obtained using commercial rigid-plastic FEM （finite element method） softw.re Deform^3D. As results show. w.en handling 3D plastic deformations, the proposed approach eliminates the need of expensive meshing and remeshing procedures w.ich are unavoidable in conventional FEM and can provide results that are in good agreement w.th finite element predictions.

关键词： meshless reproducing kernel particle method(RKPM) three-dimensional upsetting incompressibility modified penalty method

A Method of Inversing the Peak Density.of Atomic oxygen Vertical Distribution in the MLT Region From the oI (557.7 nm)Night Airglow.Intensity

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空间科学学报 2005年第5期25卷 484-489页

作者： H. Gao j. y. Xu w. yuan Laboratory for Space w.ather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 China China-Russia j.int Research Center on Space w.ather Graduate School Chinese Academy of Sciences Beijing 100039

In this paper, using the MSISE-90 model as the reference atmosphere, w. discuss the feasibility and method of deducing the peak densities of the undisturbed atomic oxygen profiles in the MLT region (the mesosphere and low.r thermosphere region) from oI (557.7 nm) night airglow.intersities. The peak densities for different seasons, latitudes and longitudes are deduced from oI (557.7nm) airglow.intensities through this expression. w. analyze the features of inversion relative errors and discuss the influence of the variations in temperature on inversion errors. The results indicate that all inversion errors are less than 5% except for those at high altitudes in the summer hemisphere. And the impact of the variations in temperature on errors is not significant.

关键词：原子氧 MLT 气辉天文