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Interpenetrated Magnesium-Tricalcium Phosphate Composite:Manufacture,Characterization and In Vitro degradation Test

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Acta Metallurgica Sinica(english Letters) 2017年第4期30卷 319-325页

作者： Mariano Casas-luna Serhii Tkachenko Miroslava Horynova Lenka Klakurkova Pavel Gejdos Sebastian Diaz-de-la-Torre ladislav Celko Jozef Kaiser edgar B. Montufar CeITeC-Central european Institute of Technology Brno University of TechnologyPurkyfnova 656/123612 00 BmoCzech Republic CIITeC-Centro de Investigacion e Innovacion Tecnologica Instituto Politocnico NacionalCerrada de CECATI02250 Mexico CityMexico

Magnesium and calcium phosphates composites are promising biomaterials to create biodegradable load-bearing implants for bone regeneration. The present investigation is focused on the design of an interpenetrated magnesium- tricalcium phosphate （Mg-TCP） composite and its evaluation under immersion test. In the study, TCP porous preforms were fabricated by robocasting to have a prefect control of porosity and pore size and later infiltrated with pure commercial Mg through current-assisted metal infiltration （CAMI） technique. The microstructure, composition, distribution of phases and degradation of the composite under physiological simulated conditions were analysed by scanning electron microscopy, elemental chemical analysis and X-ray diffraction. The results revealed that robocast TCP preforms were full infiltrated by magnesium through CAMI, even small pores below 2 μm have been filled with Mg, giving to the composite a good interpenetration. The degradation rate of the Mg-TCP composite displays lower value compared to the one of pure Mg during the first 24 h of immersion test.

关键词： Calcium phosphate Magnesium Liquid metal infiltration Spark plasma sintering Corrosion

The Teodorescu Operator in Clifford Analysis

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Chinese Annals of Mathematics,Series B 2012年第4期33卷 625-640页

作者： F.BRACKX H.de SCHePPeR M.e. luna-eLIZARRARS M.SHAPIRO Clifford Research Group Faculty of Engineering and Architecture Ghent University Belgium Instituto Politcnico Nacional Mexico City Mexico

euclidean Clifford analysis is a higher dimensional function theory centred around monogenic functions, i.e., null solutions to a first order vector valued rotation in- variant differential operator called the Dirac operator. More recently, Hermitian Clifford analysis has emerged as a new branch, offering yet a refinement of the euclidean case; it focuses on the simultaneous null solutions, called Hermitian monogenic functions, to two Hermitian Dirac operators and which are invariant under the action of the unitary group. In euclidean Clifford analysis, the Teodorescu operator is the right inverse of the Dirac operator __0. In this paper, Teodorescu operators for the Hermitian Dirac operators c9~_ and 0_~, are constructed. Moreover, the structure of the euclidean and Hermitian Teodor- escu operators is revealed by analyzing the more subtle behaviour of their components. Finally, the obtained inversion relations are still refined for the differential operators is- suing from the euclidean and Hermitian Dirac operators by splitting the Clifford algebra product into its dot and wedge parts. Their relationship with several complex variables theory is discussed.

关键词： Clifford analysis Teodorescu operator Dirac operator

ON A THeOReM OF BeRNSTeIN AND ITS APPLICATIONS TO WeIGHTeD MINIMAX SeRIeS

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Journal of Computational Mathematics 1998年第6期16卷 509-520页

作者： Francisco Perez Acosta(departamento de Analisis Matematico, Universidad de la laguna, la laguna 38271,Canary Islands, Spain) Univ la laguna Dept Anal Matemat E-38271 La Laguna Canary Isl Spain

In this paper, some results about approximation in a norm S induced by the minimax series are studied. Then a Bernstein-type theorem for the norm S is established. Finally the Bernstein theorem is applied to prove the... 详细信息

关键词： Approximation theory polynomials Bernstein theorem minimax series.

Two upper bounds for the erdos-Hooley delta-function

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Science China Mathematics 2023年第12期66卷 2683-2692页

作者： Regis de la Breteche Gerald Tenenbaum Institut de Mathematiques Universite Paris CiteSorbonne UniversiteCNRSParis F-75013France Institut elie Cartan Universite de LorraineVandoeuvre-les-NancyBP 70239France

For integer n≥1 and real u,let Δ(n,u):=|{d:d] n,e^(u)e^(u+1)}|.The erdos-Hooley deltafunction is then defined by Δ(n):=Max_(u∈R)Δ(n,u).We improve the current upper bounds for the average and normal orders of ... 详细信息

关键词： concentration of divisors average order normal order Waring’s problem

WHICH IS THe USe OF SYSTeMS THeORY IN LITeRATURe ANALYSIS？： THe DISCOVeRY OF THe PlaCe IN la MANCHA IN DON QUIXOTe

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Journal of Systems Science and Systems engineering 2017年第4期26卷 517-530页

作者： Francisco Parra-luna Complutense University of Madrid Yucatan 26 28231 Las Rozas Spain

The use of systems theory to attempt to determine which ＂place in la Mancha＂ was the one whose name Cervantes could not quite recall in his universal novel, appears to be ordained to change certain attitudes towards science held in Cervanfine literature. The reason： after four centuries of literary analysis, systemic methodology has proven able to identify the famous ＂place＂ with acceptable accuracy. Nonetheless, certain reasonable doubts persist around the suitability of a strictly scientific analysis of literature. In light of those doubts, the present article aims primarily to facilitate critique both of the systemic approach adopted and its outcome.

关键词： Don Quixote place in la Mancha systems theory epistemological totality determinantvariables

Review of Networked Microgrid Protection:Architectures,Challenges,Solutions,and Future Trends

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CSee Journal of Power and energy Systems 2024年第2期10卷 448-467页

作者： Jorge de la Cruz Ying Wu John e.Candelo-Becerra Juan C.Vasquez Josep M.Guerrero Center for Research on Microgrids(CROM) Department of Energy TechnologyAalborg University9220 AalborgDenmark Facultad de Minas Departamento de Energia Eléctrica y AutomaticaUniversidad Nacional de ColombiaSede MedellinCarrera 80 No.65-223RobledoMedellin 050041Colombia. Center for Research on Microgrids at UPC(UPC CROM) Department of Electronic EngineeringTechnical University of Catalonia(UPC)08019 Barcelona Spain ICReA Pg.Lluis Companys 2308010 BarcelonaSpain Center for Research on Microgrids at AAU(AAU CROM) AAU EnergyAalborg University(AAU)9220 Aalborg EastDenmark

design and selection of advanced protection schemes have become essential for reliable and secure operation of networked *** protection schemes that allow correct operation of microgrids have been proposed for individual systems in different topologies and ***,protection schemes for networked microgrids are still in devel-opment,and further research is required to design and operate advanced protection in interconnected *** of these microgrids in different nodes with various intercon-nection technologies increases fault occurrence and complicates protection *** paper aims to point out challenges in developing protection for networked microgrids,potential solutions,and research areas that need to be addressed for their ***,this article presents a systematic analysis of different microgrid clusters proposed since 2016,including several architectures of networked microgrids,operation modes,components,and utilization of renewable sources,which have not been widely explored in previous review ***,the paper presents a discussion on protection systems currently available for microgrid clusters,current challenges,and solutions that have been proposed for these ***,it discusses the trend of protection schemes in networked microgrids and presents some conclusions related to ***—Adaptive eprotection,microgrid cluster,microgrid,multiple microgrid,networked microgrid,real-time simulation,smart grid.

关键词： Adaptive eprotection microgrid cluster microgrid multiple microgrid networked microgrid real-time simulation smart grid

On a Shallow Water Model for the Simulation of Turbidity Currents

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Communications in Computational Physics 2009年第9期6卷 848-882页

作者： T.Morales de luna M.J.Castro Dıaz C.Pares Madronal e.D.Fernandez Nieto Analisis Matematico Facultad de Ciencias–Univ.MalagaCampus de Teatinoss/n29071-MalagaSpain Dpto.Matematica Aplicada I ETS Arquitectura–Univ.SevillaAvda.Reina Mercedes N.241012-SevillaSpain

We present a model for hyperpycnal plumes or turbidity currents that takes into account the interaction between the turbidity current and the bottom,considering deposition and erosion effects as well as solid transport of particles at the bed load due to the *** entrainment from the ambient water in which the turbidity current plunges is also *** of ambient water is neglected and the rigid lid assumption is *** model is obtained as a depth-average system of equations under the shallow water hypothesis describing the balance of fluid mass,sediment mass and mean *** character of the system is analyzed and numerical simulations are carried out using finite volume schemes and path-conservative Roe schemes.

关键词： Turbidity currents hyperbolic systems finite volume methods path-conservative schemes numerical modeling

Chronic hepatitis C in hemodialysis patients:Prevalence and liver fibrosis impact in the National Center for Renal Health in Peru

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iLIVeR 2022年第3期1卷 141-144页

作者： P.Martin Padilla-Machaca eduardo luna-Victoria Ada Cabrera Juan-Carlos Gómez-de la Torre Rocio Galloso Pedro Montes Guillermo Almenara National Hospital EsSaludLimaPerú National University of San Marcos LimaPerú National Renal Health Center EsSaludLimaPerú laboratorio Clínico Roe LimaPerú Asociacion Peruana para el estudio del Hígado(APeH) LimaPerú

Background:Hepatitis C(HCV)remains a serious public health problem in high-risk persons such as patients on chronic *** aimed to estimate the serological prevalence of HCV,the HCV viral load and genotype,and liver fibrosis stage among patients on chronic hemodialysis at the National Renal Health Center in Lima,***:From June 2019 to March 2021,all patients who received chronic hemodialysis were invited to *** who provided written informed consent were *** with HCV-positive serology underwent determination of HCV viral *** from subjects with detectable viral load,underwent determination of HCV ***,HCV infected subjects underwent determination of liver fibrosis using transitional elastography(Fibroscan 402):Metavir score:F0-F1:2.5-7.5 kPa,F2:7.6-9.5 Kpa,F3:9.6-12 Kpa,F4(Cirrhosis):12.1-75 ***:Of the 303 subjects invited to participate,174(57.4%)subjects gave their written *** age was 52 years(range 22-91)and 116(66.6%)were *** serology was positive in 35.1%of patients(61/174);however,the prevalence of positive serology with detectable viral load was 20.11%(35/174).Genotype 1a was the most prevalent(85%).The majority(83.6%)of subjects with detectable viral load had values lower than 800.000 IU/***-nine of those 35 subjects underwent elastography evaluation,and 13(44.8%)of them were found to have stage F2-F4 ***:The prevalence of HCV at the largest reference center for hemodialysis in Lima remains high,with GT1a predominance,viral load usually below 800,000 IU/mL and significant liver fibrosis.

关键词： Hepatitis C Hemodialysis Liver fibrosis HCV genotype

Hematological Parameters in Bufo arenarum Injected With Sublethal Dose of Lead Acetate

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Biomedical and environmental Sciences 1998年第1期11卷 70-74页

作者： S. I. PeRi N. e. FINK AND A. SALIBIAN(Catedra de Fisiologia Animal, Facultad de Ciencias Naturales,Universidad Nacional de la Plata (UNLP), Paseo del Bosque,1900 la Plata, Argentina Chtedra de Hematologia)(deportamento de Ciencias Bioldgices , Faculta Cátedra de Fisiología Animal Facultad de Ciencias Naturales Universidad Nacional de La Plata (UNLP) Argentina.

Lead has been recognized as a high risk toxic for most organisms including human. The effects of Pb in non-mammalian vertebrates are oprly known, particularly in anuran amphibians. The purpose of this study was to determine the effect of this metal on some hematological parameters of adult Bufo arenarum. It was found that all parameters remained unaltered within normal ranges, with the exception of reticulocyte counts which was significantly increased compared to the in controls (3. 7% vs. 0. 2 % ). It is suggested that the selective change found in reticulocyte count might be considered as an early response of a biomarker to sublethal exposition of Bufo arenarum to lead.

关键词： Hematological Parameters in Bufo arenarum Injected With Sublethal Dose of Lead Acetate