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A Pseudo-Stokes Mesh Motion Algorithm

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Advances in Applied Mathematics and Mechanics 2013年第2期5卷 194-211页

作者： Luciano Goncalves Noleto Manuel N.D.Barcelos jr. antonio C.P.Brasil jr. Universidade de Brasılia Faculdade de TecnologiaDepartamento de Engenharia MecanicaLaboratorio de Energia e Ambiente.Asa Norte.Brasılia-DFBrasil70.910-900 Universidade de Brasılia no Gama.Complexo de Educa¸c˜ao CulturaEsporte e Lazer.A rea Especial de Industria 1Setor LesteFaculdade Lote 1.Gama-DFBrasil72.444-210

This work presents a moving mesh methodology based on the solution of a pseudo flow *** mesh motion is modeled as a pseudo Stokes problem solved by an explicit finite element projection *** mesh quality requirements are satisfied by employing a null divergent velocity *** methodology is applied to triangular unstructured meshes and compared to well known approaches such as the ones based on diffusion and pseudo structural *** of the test cases is an airfoil with a fully meshed domain.A specific rotation velocity is imposed as the airfoil boundary *** other test is a set of two cylinders that move toward each other.A mesh quality criteria is employed to identify critically distorted elements and to evaluate the performance of each mesh motion *** results obtained for each test case show that the pseudo-flow methodology produces satisfactory meshes during the moving process.

关键词： Moving boundaries mesh motion strategy finite element projection methods

Buzz-pollination in Neotropical bees:genus-dependent frequencies and lack of optimal frequency for pollen release

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Insect Science 2020年第1期27卷 133-142页

作者： Conrado Augusto Rosi-Denadai Priscila Cassia Souza Araujo Lucio antonio de Oliveira Campos Lirio Cosme jr. Raul Narciso Carvalho Guedes Departamento de Entomologia Universidade Federal de VigosaVigosaMinas GeraisBrazil Departamento de Biologia Geral Universidade Federal de VigosaVigosaMinas GeraisBrazil

Over 50 genera of bees release pollen from flower anthers using thoracic vibrations,a phenomenon known as *** efficiency of this process is directly affected by the mechanical properties of the buzzes,namely the duration,amplitude,and ***,although the effects of the former two properties are well described,the role of buzz frequency on pollen release remains ***,nearly all of the existing studies describing vibrational properties of natural buzz-pollination are limited to bumblebees(Bombus)and carpenter bees(Xvlocopa)constraining our current understanding of this behavior and its ***,we attempted to minimize this shortcoming by testing whether flower anthers exhibit optimal frequency for pollen release and whether bees tune their buzzes to match these(optimal)*** true,certain frequencies will trigger more pollen release and lighter bees will reach buzz frequencies closer to this optimum to compensate their smaller buzz *** strategies were used to test these hypotheses:(i)the use of(artificial)vibrational playbacks in a broad range of buzz frequencies and amplitudes to assess pollen release by tomato plants(Solarium Ivcopersicum L.)and(ii)the recording of natural buzzes of Neotropical bees visiting tomato plants during *** playback experiment indicates that although buzz frequency does affect pollen release,no optimal frequency exists for *** addition,the recorded results of natural buzz-pollination reveal that buzz frequencies vary with bee genera and are not correlated with body ***,neither bees nor plants are tuned to optimal pollen release *** frequency of buzz-pollination is a likely consequence of the insect flight machinery adapted to reach higher accelerations,while flower plant response to buzz-pollination is the likely result of its pollen granular properties.

关键词： buzz amplitude buzz frequency floral sonication pollination stingless bees vibration

Curcumin-Loaded Electrospun Fibers: Fluorescence and Antibacterial Activity

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Advanced Fiber Materials 2020年第5期2卷 256-264页

作者： Mário César Albuquerque de Oliveira Fernando antonio Gomes da Silva jr. Mateus Matiuzzi da Costa Nikifor Rakov Helinando Pequeno de Oliveira Institute of Materials Science Federal University of Sao Francisco ValleyJuazeiroBA 48920-310Brazil

The health benefits and sensing applications of curcumin-based systems depend on their prevailing photophysical and chemi-cal properties at a specific environment-the characteristic low solubility of curcumin in water hinders high-dosage based *** circumvent this drawback,curcumin has been incorporated in hydrophobic environments in ***,electrospun fibers of Eudragit L100 were loaded with curcumin and applied in fluorescence and antibacterial assays to evaluate prevailing physical and chemical properties in *** characteristic high loading degree of curcumin(250 mg/mL in Eudragit L100 solution)preserves not only the photophysical properties of molecules(such as the intrinsic fluorescence)but also the antibacterial activity of released molecules from electrospun fibers,characterizing an important strategy for improvement in the applicability potential of natural materials.

关键词： Curcumin Fluorescence Electrospinning Hydrophobic core

Artificial equilibrium points and bi-impulsive maneuvers to observe 243 Ida

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Chinese Journal of Aeronautics 2021年第1期34卷 410-423页

作者： Allan Kardec de ALMEIDA jr.Geraldo Magela Couto OLIVEIRA antonio Fernando Bertachini de Almeida PRADO National Institute for Space Research(INPE) Sao Jose dos Campos 12227-010Brazil Federal Center for Technological Education of Minas Gerais(CEFET-MG) Belo Horizonte 30421-169Brazil

In the restricted three-body problem,the traditional Lagrange points L1 and L2 are the only equilibrium points near the asteroid 243 *** thrust generated by a solar sail over a spacecraft enables the existence of new artificial equilibrium points,which depend on the position of the spacecraft with respect to the asteroid and the attitude of the solar *** equilibrium points generate new spots to observe the body from above or below the plane of *** points are very good observational locations due to their stationary *** work provides a preliminary analysis to observe Ida through the use of artificial equilibrium points as spots combined with transfer maneuvers between *** combination can be used to observe the asteroid from more different points of view in comparison to fixed *** analyses are made for a spacecraft equipped with a solar sail and capable of performing bi-impulsive *** solar radiation pressure is used both to maintain the equilibrium condition and to reduce the costs of the transfers and/or to create transfers with longer *** is a new aspect of the present research,because it combines the continuous thrust with initial and final small impulses,which are feasible for most of the spacecraft,because the magnitudes of the impulses are very *** combined maneuvers may reduce the transfer times of the maneuvers in most of the cases,compared with the maneuvers based only on continuous *** options involved in these transfers are shown,like to minimize the fuel spent(Dv)as a function of the transfer time or to extend the duration of the travel between the *** transfer times can be useful when observations are required during the transfers.

关键词： Artificial equilibrium points Astrodynamics Orbital transfers Solar radiation pressure Solar sail

可变速电机和带PSS装置的同步电机动态性能比较

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国外大电机 2016年第2期 4-12页

作者： antonio C.padoan jr.陈辉不详哈尔滨工业大学

本文以2×320MW抽水蓄能电机为例对可变速和恒速机组的动态性能进行比较，提出了抽水蓄能电站带有标准PSS装置的同步电机案例分析，并针对此案例设计了相应的可变速系统。两种系统架构的非定常数值模拟说明了可变速系统可以改善本地和... 详细信息

本文以2×320MW抽水蓄能电机为例对可变速和恒速机组的动态性能进行比较，提出了抽水蓄能电站带有标准PSS装置的同步电机案例分析，并针对此案例设计了相应的可变速系统。两种系统架构的非定常数值模拟说明了可变速系统可以改善本地和区域电力系统振荡方式。此外，还研究了发电工况下由水泵水轮机部分负荷引起的有功功率波动问题。

关键词：空化涡带水电站电力系统稳定器抽水蓄能可变速

Symptomatic improvement in an acute, non-traumatic spine pain model with a combination of uridine triphosphate, cytidine monophosphate, and hydroxocobalamin

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Pain Studies and Treatment 2014年第1期2卷 6-10页

作者： Marco antonio Mibielli carlos Pereira Nunes Ari Boulanger Scussel jr. Mendel Suchmacher Neto Lisa Oliveira Mauro Geller Teresópolis Medical School-UNIFESO Rio de Janeiro Brazil

Rationale: In a previously published trial on spinal acute non-traumatic pain, peripheral neuro- regenerative combination of UTP, CMP and hydroxocobalamin presented unexpected analgesicproperties. Objective: To corroborate analgesiceffects of UTP, CMP and hydroxocobalamin combination in a self-paired evolutionary model. Methods: Mean VAS scores from pretreatment, V2 (5th treatment day) and V3 (10th treatment day) were plotted and statistically analyzed (ANOVA) for differences. PFQ scores from pretreatment, V2, and V3 were analyzed using the chisquare test. Results: The difference between V3 and pretreatment mean VAS scores was statistically significant (p < 0.0001). The improvement in PFQ scores throughout the study was found to be statistically significant (p < 0.0001). Conclusion: The combination of UTP, CMP and hydroxocobalamin seems to have analgesic properties in mediumterm use. The complex peripheral neu-roregenerative pharmacodynamics of this combination provides a plausible basis for this finding. Further randomized studies are needed to explore this combination for the indication of neuropathic pain due to spinal structure involvement.

关键词： Uridine Triphosphate Cytidine Monophosphate Hydroxocobalamin Analgesia

Evaluation of Renewable Energy Vulnerability to Climate Change in Brazil: A Case Study of Biofuels and Solar Energy

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Smart Grid and Renewable Energy 2015年第8期6卷 221-232页

作者： antonio Oscar jr. Wanderson Luiz Silva Vera Ruffato Renata Barreto Marcos Freitas Federal University of Rio de Janeiro Rio de Janeiro Brazil

This study aims to calculate indicators and indexes to subsidize the analysis of vulnerability and adaptation of the renewable energy sector to climate change in Brazil, focusing on biofuels and solar energy. For biofuels, in general, the Brazilian coast will be a propitious area for agricultural productivity during the XXI century, but these are areas historically intended for occupation and development of the urbanization process, that is, with limited land availability and supply for primary production. In some parts of the Northeast, Midwest and South of the country, offer for the cultivation land will be reduced. For the solar energy is observed that Brazil has area and highly expressive power for the use of this power, both today and in the coming decades, especially in the North, Northeast and Midwest. In statistical terms, the Mann-Kendal test and Sen’s Bend point to a very weak tendency to useful radiation indicator in all regions of Brazil by 2100. In addition, it is projected a significant increase in mean air temperature by the end of XXI century across the country that can mean a reduction in power conversion capability, which is sensitive to ambient temperature variations, especially in the Midwest and North of the country.

关键词： Renewable Energy Climate Change Brazil Biofuels Solar Energy

Tooth-derived stem cells: Update and perspectives

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World Journal of Stem Cells 2015年第2期7卷 399-407页

作者： Miki Taketomi Saito Karina Gonzales Silvério Márcio Zaffalon Casati Enilson antonio Sallum Francisco Humberto Nociti jr Department of Prosthodontics and Periodontics Division of PeriodonticsPiracicaba Dental SchoolUniversity of Campinas (UNICAMP)

Tissue engineering is an emerging field of science that focuses on creating suitable conditions for the regeneration of tissues. The basic components for tissue engineering involve an interactive triad of scaffolds, signaling molecules, and cells. In this context,stem cells(SCs) present the characteristics of selfrenewal and differentiation capacity, which make them promising candidates for tissue engineering. Although they present some common markers, such as cluster of differentiation(CD)105, CD146 and STRO-1, SCs derived from various tissues have different patterns in relation to proliferation, clonogenicity, and differentiation abilities in vitro and in vivo. Tooth-derived tissues have been proposed as an accessible source to obtain SCs with limited morbidity, and various tooth-derived SCs(TDSCs) have been isolated and characterized, such as dental pulp SCs, SCs from human exfoliated deciduous teeth, periodontal ligament SCs, dental follicle progenitor cells, SCs from apical papilla, and periodontal ligament of deciduous teeth SCs. However, heterogeneity among these populations has been observed, and the best method to select the most appropriate TDSCs for regeneration approaches has not yet been established. The objective of this review is to outline the current knowledge concerning the various types of TDSCs, and discuss the perspectives for their use in regenerative approaches.

关键词： Cell-based therapy Mesenchymal stem cells Dental stem cells Differentiation Tissue engineering

Thoracoscopic esophagectomy is related to better outcomes in early adenocarcinoma of esophagogastric junction tumors

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World Journal of Gastrointestinal Endoscopy 2021年第8期13卷 319-328页

作者： Flavio Roberto Takeda carlos de Almeida Obregon Yasmin Peres Navarro Diogo Turiani Hourneaux Moura Ulysses Ribeiro jr.Rubens antonio Aissar Sallum Ivan Cecconello Department of Gastroenterology University of São Paulo Medical SchoolSão Paulo 05403-000Brazil

BACKGROUND Thoracoscopic esophagectomy is related to an extended lymphadenectomy,and a high number of retrieved lymph nodes,compared to the transhiatal approach;however,its association with an improvement in overall survival(OS)is *** To compare thoracoscopic esophagectomy with transhiatal esophagectomy in patients with adenocarcinoma of the esophagogastric junction(AEGJ)in terms of survival,number of lymph nodes,and *** In total,147 patients with AEGJ were selected retrospectively from 2002 to 2019,and divided into Group A for thoracoscopic esophagectomy,and group B for transhiatal ***,disease-free survival,postoperative complications,and number of nodes,were similarly *** One hundred and thirty(88%)were male;the mean age was 64 *** A had a mean age of 61.1 years and group B 65.7 years(P=0.009).Concerning the extent of lymphadenectomy,group A showed a higher number of retrieved lymph nodes(mean of 31.89±8.2 vs 20.73±7;P<0.001),with more perioperative complications,such as hoarseness,surgical site infections,and respiratory *** both groups had similar OS rates,subgroup analysis showed better survival of transthoracic esophagectomy in patients with earlier *** Both methods are safe,having similar morbidity and mortality *** thoracoscopic esophagectomy allows a more extensive resection of the lymph nodes and may have better oncological outcomes during earlier stages of the *** studies are warranted to better evaluate these findings.

关键词： Adenocarcinoma Esophagogastric junction Transhiatal Thoracoscopic Lymph nodes Surgery