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Bioactive Materials 2017年第3期2卷 138-145页

作者： Ugo d'Amora Teresa Russo Antonio Gloria Virginia Rivieccio Vincenzo d'Anto Giacomo Negri Luigi Ambrosio Roberto de Santis Institute of Polymers Composites and BiomaterialsNational Research CouncilNaplesItaly Villa Betania Evangelical Hospital NaplesItaly department of Neuroscience Reproductive Sciences and Oral SciencesUniversity of Naples Federico IINaplesItaly Unit of dentistry Bambino GesùChildren's HospitalIRCCSRomeItaly

Over the past few years,the influence of static or dynamic magnetic fields on biological systems has become a topic of considerable *** has recently been implicated to play significant roles in the regulation of cell responses and,for this reason,it is revolutionizing many aspects of healthcare,also suggesting new opportunities in tissue *** aim of the present study was to analyze the effect of the application mode of a time-dependent magnetic field on the behavior of human mesenchymal stem cells(hMSCs)seeded on 3d additivemanufactured poly(3-caprolactone)/iron-doped hydroxyapatite(PCL/FeHA)nanocomposite scaffolds.

关键词： Additive manufacturing Scaffold Magnetic field Cell-material interaction

Representation of the quantum mechanical wavefunction by orthogonal polynomials in the energy and physical parameters

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Communications in Theoretical Physics 2020年第1期72卷 66-80页

作者： A d Alhaidari Saudi Center for Theoretical Physics PO Box 32741Jeddah 21438Saudi Arabia

We present a formulation of quantum mechanics based on the theory of orthogonal *** wavefunction is expanded over a complete set of square integrable basis where the expansion coefficients are orthogonal polynomials in the energy and physical *** about the corresponding physical systems(both structural and dynamical)are derived from the properties of these *** demonstrate that an advantage of this formulation is that the class of exactly solvable quantum mechanical problems becomes larger than in the conventional formulation(see,for example,table 3 in the text).We limit our investigation in this work to the Askey classification scheme of hypergeometric orthogonal polynomials and focus on the Wilson polynomial and two of its limiting cases(the Meixner–Pollaczek and continuous dual Hahn polynomials).Nonetheless,the formulation is amenable to other classes of orthogonal polynomials.

关键词： tridiagonal representation orthogonal polynomials recursion relation asymptotics energy spectrum phase shift

3d-printed scaffolds with 2d hetero-nanostructures and immunomodulatory cytokines provide pro-healing microenvironment for enhanced bone regeneration

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Bioactive Materials 2023年第9期27卷 216-230页

作者： Xifeng Liu Bipin Gaihre Sungjo Park Linli Li Babak dashtdar Maria d.Astudillo Potes Andre Terzic Benjamin d.Elder Lichun Lu department of Physiology and Biomedical Engineering Mayo ClinicRochesterMN55905USA department of Orthopedic Surgery Mayo ClinicRochesterMN55905USA department of Cardiovascular Medicine and Center for Regenerative Medicine Mayo ClinicRochesterMN55905USA department of Neurologic Surgery Mayo ClinicRochesterMN55905USA

Three-dimensional (3d) printing technology is driving forward the progresses of various engineering fields, including tissue engineering. However, the pristine 3d-printed scaffolds usually lack robust functions in stimulating desired activity for varied regeneration applications. In this study, we combined the two-dimensional (2d) hetero-nanostructures and immuno-regulative interleukin-4 (IL-4) cytokines for the functionalization of 3d-printed scaffolds to achieve a pro-healing immuno-microenvironment for optimized bone injury repair. The 2d hetero-nanostructure consists of graphene oxide (GO) layers, for improved cell adhesion, and black phosphorous (BP) nanosheets, for the continuous release of phosphate ions to stimulate cell growth and osteogenesis. In addition, the 2d hetero-nanolayers facilitated the adsorption of large content of immuno-regulative IL-4 cytokines, which modulated the polarization of macrophages into M2 phenotype. After in vivo implantation in rat, the immuno-functioned 3d-scaffolds achieved in vivo osteo-immunomodulation by building a pro-healing immunological microenvironment for better angiogenesis and osteogenesis in the defect area and thus facilitated bone regeneration. These results demonstrated that the immuno-functionalization of 3d-scaffolds with 2d hetero-nanostructures with secondary loading of immuno-regulative cytokines is an encouraging strategy for improving bone regeneration.

关键词： 3d-printing 2d materials Bone repair Osteo-immunomodulation Cytokines

Self-sensing concrete:from resistance-based sensing to capacitance-based sensing

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International Journal of Smart and Nano Materials 2021年第1期12卷 1-19页

作者： d.d.L.Chung Composite Materials Research Laboratory Department of Mechanical and Aerospace EngineeringUniversity at Buffalothe State University of New YorkBuffaloNYUSA

Self-sensing uses the cement-based material without sensor incor-poration to sense *** paper reviews self-sensing cementbased materials,with coverage of the well-studied resistance-based sensing as well as the less-studied capacitance-based *** review is the first that covers capacitance-based ***-based sensing is advantageous over resistance-based sensing in that no particular admixture is required,so that it is applicable to both existing and new *** contrast,resis-tancebased sensing that is comparable to capacitance-based sen-sing in stress/strain sensitivity requires conductive admixtures,such as carbon ***-based strain sensing is based on piezo-resistivity,which is associated with the resistance increasing upon tension and decreasing upon ***-based strain sensing is based on piezopermittivity,which is associated with the permittivity decreasing upon tension and increasing upon *** causes the resistance to increase and causes the permittivity to *** in temperature decreases the resistance but increases the *** review also covers the methodology of the electrical measurements.

关键词： Cement concrete sensing resistance capacitance

Nonlinear thermo-mechanical stability of eccentrically stiffened functionally graded material sandwich doubly curved shallow shells with general sigmoid law and power law according to third-order shear deformation theory

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Applied Mathematics and Mechanics(English Edition) 2017年第2期38卷 191-216页

作者： d.V.dUNG d.T.dONG Faculty of Mathematics Mechanics and Informatics Vietnam National University Hanoi 100000 Vietnam Faculty of Civil Engineering University of Transport Technology Hanoi 100000 Vietnam

In this paper, the nonlinear analysis of stability of functionally graded ma- terial （FGM） sandwich doubly curved shallow shells is studied under thermo-mechanical loads with material properties obeying the general sigmoid law and power law of four ma- terial models. Shells are reinforced by the FGM stiffeners and rest on elastic foundations. Theoretical formulations are derived by the third-order shear deformation theory （TSdT） with the von Karman-type nonlinearity taking into account the initial geometrical im- perfection and smeared stiffener technique. The explicit expressions for determining the critical buckling load and the post-buckling mechanical and thermal load-deflection curves are obtained by the Galerkin method. Two iterative algorithms are presented. The effects of the stiffeners, the thermal element, the distribution law of material, the initial imper- fection, the foundation, and the geometrical parameters on buckling and post-buckling of shells are investigated.

关键词： functionally graded material (FGM) sandwich double curved shallow shell,thermo-mechanical stability FGM stiffener elastic foundation

Pattern synthesis optimization of 3-d OdAR based on improved GA using LSFE method

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Journal of Harbin Institute of Technology(New Series) 2011年第1期18卷 96-100页

作者：龙伟军贲德 BAKHSHI ASIM d 张弓 College of Information Science and Technology Nanjing University of Aeronautics & Astronautics Computer Engineering University of Engineering and Technology

Pattern synthesis in 3-d opportunistic digital array radar(OdAR) becomes complex when a multitude of antennas are considered to be randomly distributed in a three dimensional *** order to obtain an optimal pattern,several freedoms must be constrained.A new pattern synthesis approach based on the improved genetic algorithm(GA) using the least square fitness estimation(LSFE) method is *** optimized by this method include antenna locations,stimulus states and phase *** new algorithm demonstrates that the fitness variation tendency of GA can be effectively predicted after several "eras" by the LSFE *** is shown that by comparing the variation of LSFE curve slope,the GA operator can be adaptively modified to avoid premature convergence of the *** validity of the algorithm is verified using computer implementation.

关键词： antenna radiation patterns genetic algorithm(GA) opportunistic digital array radar(OdAR) pattern synthesis the least square fitness estimation(LSFE)

Kinematic error modeling and error compensation of desktop 3d printer

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Nanotechnology and Precision Engineering 2018年第3期1卷 180-186页

作者： Shane Keaveney Pat Connolly Eoin d.O'Cearbhaill School of Mechanical and Materials Engineering UCD Engineering and Materials Science CentreDublin 4Ireland

desktop 3d printers have revolutionized how designers and makers prototype and manufacture certain *** popular fuse deposition modeling(FdM)desktop printers have enabled a shift to low-cost consumer goods markets,through reduced capital equipment investment and consumable material ***,with this drive to reduce costs,the computer numerical control(CNC)systems implemented in FdM printers are often compromised by poor accuracy and contouring *** condition is most critical as users begin to use 3d-printed components in load-bearing applications or to perform mechanical *** methods of low-cost 3d printer calibration are needed before their open-design potential can be realized in applications,including 3d-printed orthotics and *** paper applies methodologies associated with high-precision CNC machining systems,namely,kinematic error modeling and compensation coupled with standardized test methods from ISO230-4,such as the ballbar for kinematic and dynamic error measurements,to examine the influence and feasibility for use on low-cost CNC/3d printing ***,the *** and drug Administration's"Technical considerations for additive manufactured medical devices"highlighted the need to develop standards specific to additive manufacturing in regulated manufacturing *** paper shows the benefits of the methods described within ISO230-4 for error assessment,alongside applying kinematic error modeling and compensation to the popular kinematic configuration of an Ultimaker 3d printer.A Renishaw ballbar QC10 is used to quantify the Ultimaker's errors and thereby populate the error *** method quantifies machine errors and populates these in a mathematical model of the CNC ***,a post-processor can be used to compensate the printing ***,the ballbar is used to demonstrate the dramatic impact of the error compensation model on the accuracy and contouring of the Ultimaker pr

关键词： 3d printing accuracy Kinematic error modeling Kinematic error compensation Ballbar FdM3d printing ISO230-4

pde2path – A Matlab Package for Continuation and Bifurcation in 2d Elliptic Systems

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Numerical Mathematics(Theory,Methods and Applications) 2014年第1期7卷 58-106页

作者： Hannes Uecker daniel Wetzel Jens d.M.Rademacher Institut für Mathematik Universität Oldenburg26111 OldenburgGermany Universität Bremen Fachbereich MathematikPostfach 33044028359 BremenGermany

pde2path is a free and easy to use Matlab continuation/bifurcation package for elliptic systems of PdEs with arbitrary many components,on general two dimensional domains,and with rather general boundary *** package is based on the FEM of the Matlab pdetoolbox,and is explained by a number of examples,including Bratu’s problem,the Schnakenberg model,Rayleigh-Bénard convection,and von Karman plate *** serve as templates to study new problems,for which the user has to provide,via Matlab function files,a description of the geometry,the boundary conditions,the coefficients of the PdE,and a rough initial guess of a *** basic algorithm is a one parameter arclength-continuation with optional bifurcation detection and *** calculations,error control and mesh-handling,and some elementary timeintegration for the associated parabolic problem are also *** continuation,branch-switching,plotting etc are performed via Matlab command-line function calls guided by the AUTO *** software can be downloaded from ***/*** ker/pde2path,where also an online documentation of the software is provided such that in this paper we focus more on the mathematics and the example systems.

关键词： Elliptic systems continuation and bifurcation finite element method

Application and validation of a 3-d calcium,chloride,and sulfate model in Lake Okeechobee

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Ecological Processes 2014年第1期3卷 1-19页

作者： Kang-Ren Jin Mark d Shafer Zhen-Gang Ji Lead Scientist South Florida Water Management DistrictP.O.Box 24680West Palm BeachFL 33416-4680USA Senior Environmental Engineer US Army Corps Engineers701 San Marco BlvdJacksonvilleFL 32207-8175USA Adjunct Professor Department of Civil EngineeringCatholic University of AmericaPangborn HallRoom G12WashingtonDC 20064USA

Introduction: The calibration, verification, and validation of calcium (Ca), chloride (Cl), and sulfate (SO_(4)) module ofthe Lake Okeechobee Environment Model (LOEM) was completed. The integrated model could simulate Ca, Cl, andSO_(4) concentrations and transport due to wind driven currents and waves from 1 Oct 1999 to 30 Sept 2009 in LakeOkeechobee. The enhanced model was also used to estimate lake water quality effects resulting from differentmanagement scenarios that include discharges from planned aquifer storage and recovery (ASR) ***: The fate and transport processes of Ca, Cl, and SO_(4) are controlled by their reactivity and their hydrodynamictransport. Reactivity includes chemical, biological, and bio-uptake processes (IJRSA 33:2233-2260, 2012). Hydrodynamictransport includes advection of water current, diffusion, and turbulent mixing within the water column. The depositionand resuspension on the water-sediment bed interface is also included. The mathematical equations for describing Ca,Cl, and SO_(4) substances, including heavy metal and total organic carbon (TOC), are ***: Both the statistical results and the time series comparisons indicate that the simulation of Ca, Cl, and SO_(4) aregenerally simulated well by the LOEM. The root mean square error over the variance rage is Cl dSO_(4) d SO_(4) concentrations in the lake were largely controlled by water temperature and lakeevaporation. Inflows to the lake can also have localized effects on chloride variations. Shallow water depth and highevaporation contribute to high Cl/Ca/ SO_(4) concentration in the lake.

关键词： Ca Cl SO_(4)modeling Lake Okeechobee Long-term simulation Environmental modeling

Kinematics of whip spider pedipalps: a 3d comparative morpho-functional approach

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Integrative Zoology 2022年第1期17卷 156-167页

作者： Michel SCHMIdT Roland R.MELZER Russell d.C.BICKNELL Bavarian State Collection of Zoology Bavarian Natural History CollectionsMunichGermany department Biology II Ludwig-Maximilians-Universität MünchenMunichGermany GeoBio-Center Ludwig-Maximilians-Universität MünchenMunichGermany Palaeoscience Research Centre School of Environmental and Rural ScienceUniversity of New EnglandArmidaleAustralia

Amblypygi are tropical and subtropical ambush predators that use elongated,raptorial pedipalps for different *** pedipalp use in predation and courtship has been explored in videography in vivo analyses,kinematic ex vivo examination of these appendages has not been ***,we rectify this lack of data by using microCT scans to 3d-kinematically model the appendage morphology and the range of motion(ROM)of the joints for damon medius and Heterophrynus *** illustrate the successful application of this technique to terrestrial euarthropods in determining the maximum ROM values for each pedipalp *** also note that,in life,these values would be lower due to motion restricting structures like tendons,arthrodial membranes,and *** further compare our maximum values obtained here with data from video-based motion *** ROM of each joint shows the greatest flexibility in the femur-tibia joint(140–150°),the lowest in the basitarsus-claw joint(35–40°).ROM in the tibia-basitarsus joint is markedly distinct(***:44°;***:105°).This disparity reflects how *** uses the joint in the capture basket,while *** uses the femur-tibia joint to form the capture *** further illustrate notable vertical motion of the *** pedipalp compared to *** difference reflects the retro-ventral trochanter apophysis of *** study opens the possibility to further whip spider kinematic *** of other taxa using this approach will result in a more comprehensive understanding of the ecological significance and ethological implications of this unique arachnid group.

关键词： 3d kinematic analyses Amblypygi arthropod joints Autodesk Maya damon medius Heterophrynus elaphus range of motion analyses