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Structural optimization of patient-specific temporomandibular joint replacement implants for additive manufacturing:novel metrics for safety evaluation and biomechanical performance

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Bio-Design and manufacturing 2022年第2期5卷 333-347页

作者： manuel Pinheiro Anouar Krairi Robin Willaert maria C.costa Wim Van Paepegem mechanics of materials and Structures(mmS) Ghent UniversityGhentBelgium materials Innovation Institute(m2i) DelftThe Netherlands Department of Oral and maxillofacial Surgery University Hospitals Leuven LeuvenBelgium 4 Department of Head and Neck SurgeryGhent University HospitalGhentBelgium

total temporomandibular joint(tmJ)replacement is recommended only when there is irreversible damage to the joint and no conservative treatment can provide functional *** stock and custom-made tmJ implants have been made available;however,retrospective and comparative studies were unable to find significant differences between the two types of *** introduction of additive manufacturing(Am)techniques in medical practice allows for a greater freedom of design and a higher degree of device *** combination of Am with structural optimisation may streamline development and provide the key for fabricating biomechanic ally enhanced tmJ *** this study,structural optimis ation techniques were applied to develop and numerically validate a patient-specific tmJ *** biomechanical behaviour of each intermediate tmJ design was assessed under four different nominal and maximum biting tasks using finite element *** addition,a new set of metrics were proposed to compare each design regarding biomechanical performance and implant *** results suggest that 55-82%of the natural/intact strain patterns can be recovered with the finally selected tmJ *** represents an increase of 15%in biomechanical performance for incisor biting,15%for right molar biting,17%for left molar biting and a decrease of 2%for left group biting compared with the initial *** results also suggest that load transfer at the proximal ramus reduces the implant’s impact on the mandible’s strain ***,structural optimisation allows for a volume reduction of up to 44%with a minimum loss of implant safety and biomechanical performance.

关键词： temporomandibular joint Additive manufacturing Implant safety Biomechanical performance Finite element analysis

Contribution of inrush current to mechanical failure of power transformers windings

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High Voltage 2019年第4期4卷 300-307页

作者： Rafael m.R.Barros Edson Gda costa Jalberth F.Araujo Filipe L.mde Andrade tarso V.Ferreira Department of Electrical Engineering Federal University of Campina GrandeAprigio Veloso St.882Campina GrandeBrazil

this work presents a study regarding the contribution of inrush current to the occurrence of mechanical fatigue in windings of a power transformer and,consequently,the impact of that phenomenon on the equipment's *** order to perform the study,electromagnetic transient simulations were used to determine the inrush current in a three-phase transformer ***,three-dimensional simulations,based on the finite element method,were performed to determine the electromechanical stresses in the equipment windings,under the effect of the inrush ***,the methods of critical plans and Palmgren–miner were applied to perform the fatigue *** the results,the impact of inrush current on the integrity of the transformer's windings was determined,as well as,to estimate the reduction of lifespan of the equipment due to inrush *** number of inrushes needed for the total reduction of lifespan of the equipment due to mechanical fatigue was also *** results can be used in the transformers design stage,with the purpose of assisting the evaluation of mechanical withstand of equipment,which can minimise the possibility of failure and increase its lifespan.

关键词： winding fatigue power

Lagged Coherence of Photon Emissions and Spectral Power Densities between the Cerebral Hemispheres of Human Subjects during Rest Conditions: Phase Shift and Quantum Possibilities

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World Journal of Neuroscience 2016年第2期6卷 119-125页

作者： J. N. costa B. t. Dotta m. A. Persinger Behavioural Neuroscience Program Laurentian University Sudbury Canada Biology Department Laurentian University Sudbury Canada Psychology Department Laurentian University Sudbury Canada Biomolecular Sciences Program Laurentian University Sudbury Canada

Photon counts about 15 cm from the left and right sides of the head while subjects sat quietly during baseline conditions within a hyper-dark chamber were measured by photomultiplier units. Lag/lead analyses for photon emissions between the two hemispheres indicated a weak but statistically significant correlation between the amplitude fluctuations that were separated by about 800 to 900 ms. Analyses of the spectral power densities of photon amplitude variations from the left and right hemispheres revealed peak values between 2 and 3 Hz which were equivalent to a difference of about 900 ms. the radiant flux densities were estimated to be in the order of 10?12 W?m?2 and to include the equivalence of about 107 neurons. Our calculations, which accounted for the small magnitude of the strength of the interhemispheric coefficients, suggest that the coherence could be strongly correlated with processes associated with the unmyelinated axons with diameters between 400 to 800 nm, the visible wavelengths, within the corpus callosum. When the ratio of the phase shift was applied to the Aharanov-Bohm equation, the time required for a photon-related electron to be within a cerebral magnetic field was the same duration as a single orbit of an electron and a photon’s traversal latency across a neuronal plasma membrane. We suggest that the peak photon decoherence between the two cerebral hemispheres may reveal a neuronal-quanta substrate to the conditions associated with consciousness.

关键词： Biophotons Interhemispheric Correlations Imagination Human Brain Quantitative EEG (QEEG) Visualization Corpus Callosum Aharanov-Bohm Effect

Lithium bis(trifluoromethanesulfonyl)imide blended in polyurethane acrylate photocurable solid polymer electrolytes for lithium-ion batteries

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Journal of Energy Chemistry 2021年第11期30卷 485-496,I0011页

作者： Cristian mendes-Felipe J.C.Barbosa R.Gonsalves D.miranda C.m.costa J.L.Vilas-Vilela S.Lanceros-mendez BCmaterials Basque Center for MaterialsApplications and NanostructuresUPV/EHU Science Park48940 LeioaSpain macromolecular Chemistry Group(LABQUImAC) Department of Physical ChemistryFaculty of Science and TechnologyUniversity of the Basque Country(UPV/EHU)Barrio Sarriena s/nE-48940 LeioaSpain Center of Physics University of MinhoCampus of Gualtar4710-057 BragaPortugal Center of Chemistry University of MinhoCampus of Gualtar4710-057 BragaPortugal Ai–School of technology IPCABarcelosPortugal Ikerbasque Basque Foundation for Science48009 BilbaoSpain

the increased demand of electronic devices promotes the development of advanced and more efficient energy storage devices, such as batteries. Lithium-ion batteries (LIBs) are the most studied battery systems due to their high performance. Among the different battery components, the separator allows the control of lithium ion diffusion between the electrodes. to overcome some drawbacks of liquid electrolytes, including safety and environmental issues, solid polymer electrolytes (SPEs) are being developed. In this work, a UV photocurable polyurethane acrylate (PUA) resin has been blended with lithium bis(trifluoromethanesulfonyl) imide (LitFSI) up to 30 wt% LitFSI content to reach a maximum ionic conductivity of 0.0032 mS/cm at room temperature and 0.09 mS/cm at 100 ℃. those values allowed applying the developed materials as photocurable SPE in Swagelok type Li/C-LiFePO_(4) half-cells, reaching a battery discharge capacity value of 139 mAh.g^(−1) at C/30 rate. those results, together with the theoretical studies of the discharge capacity at different C-rates and temperatures for batteries with LitFSI/PUA SPE demonstrate the suitability of the developed photocurable SPE for LIB applications.

关键词： Solid polymer electrolytes Photocuring Polyurethane acrylate LitFSI Li-ion batteries

Effect of Cu-ZnO-Al_2O_3 supported on H-ferrierite on hydrocarbons formation from CO hydrogenation

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Chinese Journal of Catalysis 2016年第3期37卷 378-388页

作者： J.H.Flores m.E.H.maia da costa m.I.Pais da Silva 里约热内卢天主教大学生物化学系里约热内卢天主教大学物理系

methanol synthesis catalysts based on Cu, Zn and Al were prepared by three methods and subsequently mixed with H-ferrierite zeolite in an aqueous suspension to disperse the catalysts over the support. these materials were characterized by X-ray diffraction, N2 adsorption, transmission electron microscopy, temperature programmed reduction, NH3 and H2 temperature-programmed desorption, and X-ray photoelectron spectroscopy. they were also applied to the CO hydrogenation reaction to produce dimethyl ether and hydrocarbons. the catalysts were prepared by coprecipitation under low and high supersaturation conditions and by a homogeneous precipitation method. the preparation technique was found to affect the precursor structural characteristics, such as purity and crystallinity, as well as the particle size distribution of the resulting catalyst. Low supersaturation conditions favored high dispersion of the Cu species, increasing the methanol synthesis catalyst＇s metallic surface area and resulting in a homogeneous particle size distribution. these effects in turn were found to modify the zeolite properties, promoting both a low micropore volume and blockage of the zeolite acid sites. the effect of the methanol synthesis catalyst on the reaction was verified by the correlation between the Cu surface area and the CO conversion rate.

关键词： methanol synthesis catalyst Low supersaturation precipitation High supersaturation precipitation Syngas Hydrotalcite Hydrocarbon Dimethyl ether

Exploring the synthesis conditions to control the morphology of gold-iron oxide heterostructures

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Nano Research 2019年第8期12卷 1781-1788页

作者： Pablo tancredi Luelc Souza da costa Sebastian Calderon Oscar moscoso-Londono Leandro m. Socolovsky Paulo J. Ferreira Diego muraca Daniela Zanchet marcelo Knobel Laboratory of Amorphous Solids INTECINFaculty of EngineeringUniversity of Buenos Aires - CONICETBuenos AiresCP C1063ACVArgentina Department of Inorganic Chemistry Institute of ChemistryUniversity of Campinas (UNICAMP)CP615413083-970CampinasSPBrazil Brazilian Nanotechnology National Laboratory (LNNano) Rua Giuseppe Maximo Scolfaro 10000CampinasSPBrazil International Iberian Nanotechnology Laboratory (INL) Av. Mestre Jose Veiga s/n4715-330 BragaPortugal “Gleb Wataghin” Institute of Physics University of Campinas (UNICAMP)CEP 13083-859CampinasSPBrazil Autonomous University of manizales Antigua Estacion del FerrocarrilManizalesCP 170001Colombia Facultad Regional Santa Cruz Universidad Tecnoldgica Nacional - CIT Santa Cruz (CONICET)- Av delos Inmigrantes 555Rio GallegosSanta CruzArgentina materials Science and Engineering Program The University of Texas at AustinAustinTexas 78712USA

Gold-iron oxide nano-heterostructures with a clear and well-defined morphology were prepared via a seed-assisted method. the synthesis process and the events of heterogeneous nucleation during the decomposition of the iron precursor were carefully studied in order to understand the mechanism of the reaction and to tailor the architecture of the fabricated heterostructures. When employing Au seeds of 3 and 5 nm, nanoparticles with a dimer-like morphology were produced due to the occurrence of a single iron oxide nucleation event. Otherwise, multi-nucleation events could be favored by two mechanisms:(i) by the incorporation of a reducing agent and the slowing down of the heating protocol, leading to a core-shell system;(ii) by the increase of the Au seed size to 8 nm, leading to a flower-like system. Further increase of the Au seed size to 12 nm using similar synthesis conditions promotes the homogeneous nucleation and growth of the iron oxide phase, without formation of heterostructures. An in-depth study was performed on the gold-iron oxide heterostructures to confirm the epitaxial growth of the oxide domain over the Au seed and to analyze the elemental distribution of the components within the heterostructures. Finally, it was found that the modification of the plasmonic properties of the Au nanoparticles are strongly influenced by the architecture of the heterostructure, with a more pronounced damping effect for the systems produced after multi-nucleation events.

关键词： nanoparticles gold-iron oxide heterostructures heterogeneous nucleation epitaxial growth HR-microscopy

Valorization of the agro-industrial by-products of bacupari(Garcinia brasiliensis(mart.))through production of flour with bioactive properties

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Food Bioscience 2022年第1期45卷 377-385页

作者： Anely maciel de melo Rafaela Cristina turola Barbi Bruno Patrício costa mˆonica Ikeda Danielle Carpine Rosemary Hoffmann Ribani Food Engineering Graduate Program Federal University of ParanaDepartment of Chemical Engineering81531-990CuritibaPRBrazil

Brazil has a wide variety of fruits that remain insufficiently *** encourage the use of one such fruit,the bacupari((Garcinia brasiliensis(mart.)),the current study produced flours from its by-products(the peel and seed)at two maturation stages and subsequently evaluated their proximate composition,physical,antioxidant,bioactive,microstructural and thermal *** results revealed that the flours have a high in fiber content(>15%)and are a potential source of protein(>5%).Seed flour has an energy value similar to that of wheat flour and other conventional *** flour micrographs indicate the presence of starch,a fact confirmed by viscosity *** flours contain phenolic compounds and exhibit antioxidant activity,especially the unripe peel *** the compounds identified by chromatography,those present in the greatest concentrations were quinine(≅111μg/g),p-coumaric acid(≅25μg/g),m-coumaric acid(≅15μg/g),and formononetin(≅21μg/g),all of which are known to have several human health *** flour crystallinity diminished as the fruit *** flour exhibited similar thermal transitions but less thermal stability than seed *** summary,this study revealed that flours produced from the peel and seeds of bacupari,which are generated in large quantities as agro-industrial by-products,can be used as alternative ingredients in various sectors of the food industry.

关键词： Antioxidant activity Bacupari fruit Seed Peel Phenolic compounds

Eriobotrya japonica fruits and its by-products:A promising fruit with bioactive profile and trends in the food application–A bibliometric review

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Food Bioscience 2022年第6期50卷 1440-1449页

作者： Bruno Patricio costa mônica Ikeda Anely maciel de melo Fillemon Edyllin Silva Bambirra Alves Danielle Carpiné Rosemary Hoffmann Ribani Department of Chemical Engineering Federal University of ParanaCuritibaBrazil

Due to the researchers’pursuit for bioactive compounds to perform biological activities beneficial for human health,many plants species have been ***,loquat(Eriobotrya japonica),a subtropical plant originated in south-central China and is nowadays cultivated in more than 30 countries across the globe is drawing ***,its leaves and branches are processed into important pharmaceuticals while its fruit(pulp and peel)still remain insufficiently exploited being consumed mainly in *** aim of this work is to conduct a bibliometric survey throughout the Web of Science©(WOS)main Collection and Dimensions database to highlight and correlate the research that has been carried out on this *** goals are to discover the extent of the research that has already been conducted,from which fields of knowledge the research has been approached,and understand the study trends that point toward future applications in the food *** the data obtained by the up-to-date bibliometric analysis was possible to verify that the plant has been well explored in the medicinal,chemical,and pharmaceutical sector,while the fruit,especially their seed and their starch has been highlighted in the medicinal field or food science but with no extensive industrial *** 112 papers were published regarding the loquat seeds and only 4 studied their by-products which are rich in bioactive compounds and therefore have great potential for food applications.

关键词： Seed Antioxidants Non-conventional starch Biodegradable films

Record of Early tonian mafic magmatism in the central Espinhaco(Brazil):New insights for break-up of the Neoproterozoic landmass ancestor of Sao Francisco-Congo paleocontinent

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Geoscience Frontiers 2020年第6期11卷 2323-2337页

作者： Helen F.moreira AndréDanderfer Alice F.O.costa Samuel m.Bersan Cristiano C.Lana Gláucia N.Queiroga Post Graduate Program of Department of Geology Mine SchoolFederal University of Ouro PretoBrazil Department of Geology Mine SchoolFederal University of Ouro PretoBrazil

Petrological characterization,U-Pb geochronology,Lu-Hf analyses and major and trace element data from mafic intrusions in the Central Espinhaco(central portion of the Brazilian shield)are used here to investigate the geological significance of the Early Neoproterozoic magmatism in the context of the Sao Francisco-Congo *** mafic bodies are represented by medium to coarse-grained metagabbros with plagioclase,amphibole and *** U-Pb isotopic data from two samples yielded weighted mean 206pb/238U ages of 895±3.4 ma(mSWD=1.7)and 896±2.4 ma(mSWD=0.64),regarded as the best estimates for the crystallization age of these mafic *** and trace element data(including REEs)show that the gabbros originated from a subalkaline tholeiitic magma,typical of intraplate *** rocks are slightly enriched in LREEs and LILEs and depleted in *** new isotope and geochemical data,along with regional knowledge,indicate that these metagabbros mark the beginning of an important tonian-age extensional tectonic event of the landmass of which the Sao Francisco-Congo paleocontinent was part(Rodinia supercontinent or Central African block?).We furthermore suggest that these rocks belong to a prominent suite of tonian-age mafic rocks that mark a diachronic breakup attempt of this landmass which may have occurred from south to north along the Espinhaco mountain range.

关键词： mafic rocks Espinhaco basin Sao Francisco-Congo paleocontinent tonian rifting U–Pb geochronology