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Dendritic Growth, Eutectic Features and Their Effects on Hardness of a Ternary Sn–Zn–Cu Solder Alloy

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Acta Metallurgica Sinica(English Letters) 2017年第6期30卷 528-540页

作者： Bismarck luiz Silva Rodrigo Valenzuela Reyes Amauri Garcia Joséeduardo Spinelli Department of Materials Engineering Federal University of Rio Grande do Norte-UFRNNatalRN 59078-970Brazil Department of Materials Engineering Federal University of Sao Carlos-UFSCarSao CarlosSP 13565-905Brazil Department of Manufacturing and Materials Engineering University of CampinasUNICAMPCampinasSP 13083-860Brazil

The present investigation is based on the results of a directionally solidified （DS） Sn-9 wt%Zn-2 wt%Cu alloy, including primary/secondary/tertiary dendrite arm spacings of the Sn-rich matrix, the morphologies of the eutectic mixture and the corresponding interphase spacing, the nature and proportion of the Cu-Zn intermetallic compound （IMC）. The main purpose is to establish interrelations of these microstructure features with experimental solidification thermal parameters, such as cooling rates and growth rates （v）, macrosegregation and hardness. Such interrelations are interesting for both industry and academy since they represent a tool permitting the preprogramming of final properties based on the design of the microstructure. In the case of Sn-Zn-Cu alloys, hardly anything is known about the combined effects of the length scale of the microstructure and fraction and distribution of the primary IMC on hardness. The alloy microstructure is composed of a β-Sn dendritic region, surrounded by a eutectic mixture of α-Zn and β-Sn phases and the γ-Cu5Zn8 IMC. The eutectic interphase spacing varies in the range 1.2-3.6 μm, with the α-Zn phase having a globular morphology for ν 〉 0.5 mm/s and a needle-like morphology for ν 〈 0.3 mm/s. A modified Hall-Petch-type experimental expression relating hardness to the interphase spacing is proposed.

关键词： Sn-Zn-Cu solder alloy Solidification Microstructure Eutectic morphology Hardness

Predictors of residual force enhancement in voluntary contractions of elbow flexors

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Journal of Sport and Health Science 2018年第3期7卷 318-325页

作者： Heiliane de Brito Fontana Daiani de campos Raphael luiz Sakugawa Biological Sciences Center Federal University of Santa CatarinaCampus Reitor Joao David Ferreira LimaFlorianopoilsSC 88040-900Brazil Biomechanic Laboratory Federal University of Santa CatarinaCampus Reitor Joao David Ferreira LimaFlorianopolisSC 88040-900Brazil

Background:The steady-state increase in muscle force generating potential following a lengthening contraction is called residual force enhancement(RFE).In this study,we aimed to test for differences in torque,electromyographic activity(EMG),and the associated neuromuscular efficiency(NME)between isometric voluntary contractions of elbow flexors preceded and not preceded by a lengthening *** dependence of such differences on(i)stretch amplitude,(ii)the region of the force-length(FxL)relationship where contraction occurs,and(iii)the individual's ability to produce(negative)work during the stretch was ***:Sixteen healthy adults participated in the *** flexor torque,angle,and biceps brachii EMG for purely isometric contractions(reference contractions)and for isometric contractions preceded by active stretches of 20°and 40°were measured at the ascending,plateau,and descending regions of subject-specific FxL *** contractions were performed in an isokinetic ***-factor(stretch×FxL region)repeated measures analysis of variance ANOVAs was used to analyze the effect of active stretch on EMG,torque,and NME across *** relationships between mechanical work during stretch-calculated as the torque-angular displacement integral-and the changes in EMG,torque,and NME were analyzed using Pearson ***:In general,torque,EMG,and NME following active stretches differed from the values observed for the purely isometric reference *** although the detailed effects of active stretch on torque and EMG differed between regions of the FxL relationship,NME increased by about 19%for all muscle *** to 30%of the interindividual variability in torque generating potential change in response to active stretching was accounted for by differences in(negative)work capacity between ***:Our results suggest that(i)RFE contributes to"flatten"the elbow flexor torque-angle relationship,favoring

关键词： Force-length History-dependent properties Neuromuscular efficiency Upper limb Voluntary contractions

Zeta potential measurement on lithium lanthanum titanate nanoceramics

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Particuology 2016年第1期14卷 69-72页

作者： Carlos Ricardo Milian Pila eduardo Perez Cappe Yodalgis Mosqueda Laffita Oswaldo luiz Alves Institute of Materials Science and Technology (IMRE) Havana University Havana CP 10400 Cuba Solid state Chemistry Laboratory Institute of Chemistry Campinas University Campinas CP 13083-970 SP Brazil

The zeta potential, isoelectric point, and agglomeration of ***3 （LLTO） nanoparticles dispersed in aqueous media at different ionic strengths have been studied. The zeta potential was determined from electrophoretic mobility measurements, according to Smoluchowski＇s equation, for Li0.5La0.5TiO3 suspen- sions in NaCl and KCI electrolytes with ionic strengths of 1, 10, and 100 mmol/dm3. The isoelectric point （IEP）, zeta potential （ζ）, and the agglomeration were shown to strongly depend on the ionic strength of the Li0.5La0.5TiO3 aqueous colloidal suspension in both NaCI and KCI electrolytes, which allows the deter- mination of the effects of environmental conditions for ***3 manipulation in aqueous colloidal systems. The suspensions of Li0.5La0.5TiO3 nanoparticles reach the IEP in the pH range 0f3-5. The （ of Li0.5La0.5TiO3 nanoparticles varied from positive to negative values with a pH increase, which allows for the control of the surface charge depending on the purpose. The pH range of 7-g and an ionic strength ≤1 mmol/dm3 are recommended as the most suitable conditions for both the LLTO colloidal shaping techniques application and the LLTO-based nanocomposite formation.

关键词： Titanate Nanoparticles Zeta potential Colloidal suspension

Biliary tract reconstruction using jejunal tube:an experimental study in dogs

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Hepatobiliary & Pancreatic Diseases International 2009年第2期8卷 179-185页

作者： Eliane Anrain Trentini eduardo Crema Juan Carlos Llanos Mauro Masson Lerco luiz Alberto Magna luiz Sergio Leonardi State University of Campinas Faculty of Medical SciencesDepartment of Surgery Federal University of Triangulo Mineiro So Paulo State University "Júlio de Mesquita Filho" Faculty of Medicine of BotucatuDepartment of Surgery and Orthopedics

BACKGROUND:To physiologically reconstruct the biliary tract,Crema et al suggested the application of the Monti principle to the biliary tract,already used in humans for the urinary *** this technique,a jejunal segment is transversely *** study aimed to evaluate the efficacy of jejunal tube interposition between the common bile duct and duodenum in ***:Thirteen dogs underwent a laparoscopic common bile duct ligature,followed by a biliodigestive connection by jejunal tube interposition after one *** levels of glutamic-pyruvic and glutamic-oxalacetic transaminases,total bilirubins,alkaline phosphatase and gamma-glutamyltransferase were assessed before surgery and thereafter weekly until euthanasia,which was performed 6 weeks after biliodigestive ***:Data on 9 dogs were analyzed *** dogs presented with obstructive jaundice after common bile duct ligature,as confirmed by biochemical *** showed a statistically significant reduction in cholestasis after biliodigestive connection by jejunal tube interposition and were healthy until the end of the ***:A statistically significant reduction was seen in total bilirubin and canalicular enzymes(alkaline phosphatase and gamma-glutamyltransferase)in the 9 dogs 6 weeks after biliodigestive connetion by jejunal tube interposition.

关键词： biliary tract surgical procedures monti principle obstructive jaundice

Raman scattering study of the phonon dispersion in twisted bilayer graphene

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Nano Research 2013年第4期6卷 269-274页

作者： Jessica campos-Delgado luiz G. Cangado Carlos A. Achete Ado Jorio Jean-Pierre Raskin Institute of Information and Communication Technologies Electronics andApplied Mathematics (ICTEAM) Universite catholique de Louvain Louvain-la-Neuve 1348 Belgium Departamento de Fisica Universidade Federal de Minas Gerais Belo Hofizonte MG 30123-970 Brazil Divisao de Metrologia de Materiais Instituto Nacional de Metrologia Qua/Made e Tecnologia (INMETRO) Xerem RJ 25250-020 Brazil

Bilayer graphene with a twist angle O between the layers generates a superlattice structure known as a Moir6 pattern. This superlattice provides a O-dependent q wavevector that activates phonons in the interior of the Brillouin zone. Here we show that this superlattice-induced Raman scattering can be used to probe the phonon dispersion in twisted bilayer graphene （tBLG）. The effect reported here is different from the widely studied double-resonance in graphene-related materials in many aspects, and despite the absence of stacking order in tBLG, layer breathing vibrations （namely ZO＇ phonons） are observed.

关键词： twisted bilayer graphene Raman spectroscopy phonon branches

Mapping fractional landscape soils and vegetation components from Hyperion satellite imagery using an unsupervised machinelearning workflow

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International Journal of Digital Earth 2018年第7期11卷 670-690页

作者： Michael J.Friedel Massimo Buscema luiz eduardo Vicente Fabio Iwashita Andréa Koga-Vicente Hydrogeology Department GNS ScienceLower HuttNew Zealand Mathematical&Statistical Sciences University of ColoradoDenverCOUSA Semeion Institute RomeItaly Satellite Monitoring Unit Brazilian Corporation of Agricultural Research-EMBRAPACampinasBrazil Earth Sciences Department University of FlorenceFlorenceItaly Center for Meteorological and Climatological Research in Agriculture University of CampinasCampinasBrazil

An unsupervised machine-learning workflow is proposed for estimating fractional landscape soils and vegetation components from remotely sensed hyperspectral *** workflow is applied to EO-1 Hyperion satellite imagery collected near Ibirací,Minas Gerais,*** proposed workflow includes subset feature selection,learning,and estimation *** training with landscape feature class realizations provide a hypersurface from which to estimate mixtures of soil(e.g.0.5 exceedance for pixels:75%clay-rich Nitisols,15%iron-rich Latosols,and 1%quartz-rich Arenosols)and vegetation(e.g.0.5 exceedance for pixels:4%Aspen-like trees,7%Blackberry-like trees,0%live grass,and 2%dead grass).The process correctly maps forests and iron-rich Latosols as being coincident with existing drainages,and correctly classifies the clay-rich Nitisols and grasses on the intervening *** classifications are independently corroborated visually(Google Earth)and quantitatively(random soil samples and crossplots of field spectra).Some mapping challenges are the underestimation of forest fractions and overestimation of soil fractions where steep valley shadows exist,and the under representation of classified grass in some dry areas of the Hyperion *** preliminary results provide impetus for future hyperspectral studies involving airborne and satellite sensors with higher signal-to-noise and smaller footprints.

关键词： Hyperspectral machine learning remote sensing soils and vegetation unsupervised workflow

3′-UTR of the SARS-CoV-2 genome as a possible source of piRNAs

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Genes & Diseases 2023年第3期10卷 668-670页

作者： María Teresa Hernández-Huerta Laura Pérez-campos Mayoral Carlos Alberto Matias-Cervantes Carlos Romero Díaz Eli Cruz Parada eduardo Pérez-campos Mayoral Rafael Baltiérrez-Hoyos Margarito Martínez Cruz Gabriel Mayoral Andrade eduardo Pérez-campos CONACyT Faculty of Medicine and SurgeryAutonomous University“Benito Juárez”of Oaxaca(UABJO)Oaxaca 68020Mexico Research Center Faculty of Medicine UNAM-UABJOAutonomous University“Benito Juárez”of Oaxaca(UABJO)Oaxaca 8020Mexico National Technology of Mexico/IT Oaxaca Oaxaca de JuárezOaxaca 68030Mexico

SARS-CoV-2 is the causal agent of the COVID-19 pandemic. This is a single-stranded RNA beta-coronavirus that is comprised of a 5′ and 3′-untranslated region (UTR) in its non-coding RNA (ncRNA) region. The P-element-induced wimpy testis (PIWI)-interacting RNAs (piRNAs) are ncRNA sequences that bind to transposons and interfere with the translation of new genes. Here, we search for short sequences in the non-coding regions, corresponding to 28 nucleotides (nt). These start from a uracil and have a conserved region of at least 10 nt of homology with the previously reported piRNAs. The aim of this work was to identify piRNA-like sequences in the 3′-UTR of SARS-CoV-2 from the reported Wuhan Patient's genome sequence (GenBank: MN908947.3).

关键词： piRNA sequences piRNAs

Co-Simulation of an SRG Wind Turbine Control and GPRS/EGPRS Wireless Standards in Smart Grids

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IEEE/CAA Journal of Automatica Sinica 2021年第3期8卷 656-663页

作者： Andre luiz de Oliveira Carlos eduardo Capovilla Ivan Roberto Santana Casella JoséLuis Azcue-Puma Alfeu J.Sguarezi Filho University of Sao Paulo Sao Paulo 05508-010Brazil Federal University of ABC Santo Andre 09210-580Brazil

Wind energy can be considered a push-driver factor in the integration of renewable energy sources within the concept of smart *** its full deployment,it requires a modern telecommunication infrastructure for transmitting control signals around the distributed generation,in which,the wireless communication standards stand out for employing modern digital modulation and coding schemes for error correction,in order to guarantee the power plant *** some developing countries,such as Brazil,the high penetration of commercial mobile wireless standards GPRS and EGPRS(based on GSM technology)have captivated the interests of the energy sector,and they now seek to perform remote monitoring and control *** this context,this article presents a comparative performance analysis of a wireless control system for a wind SRG,when a GPRS or EGPRS data service is *** system performance is analyzed by co-simulations,including the wind generator dynamics and the wireless channel *** satisfactory results endorse the viability and robustness of the proposed system.

关键词： General packet radio service(GPRS)/enhanced GPRS(EGPRS) smart grids switched reluctance generator(SRG) wind energy wireless communications

Comprehensive analysis of HFE gene in hereditary hemochromatosis and in diseases associated with acquired iron overload

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World Journal of Hepatology 2019年第2期11卷 186-198页

作者： Wagner Narciso de campos Juliana Doblas Massaro eduardo luiz Rachid Can?ado Cláudia Emília Vieira Wiezel Aguinaldo luiz Sim?es Andreza Correa Teixeira Fernanda Fernandes de Souza Celso Teixeira Mendes-Junior Ana de Lourdes Candolo Martinelli eduardo Ant?nio Donadi Division of Clinical Immunology Department of MedicineRibeir?o Preto Medical SchoolUniversity of S?o Paulo Department of Gastroenterology Clinical Gastroenterology and Clinical Hepatology of Clinical HospitalUniversity of S?o Paulo School of Medicine Department of Genetics Ribeir?o Preto Medical SchoolUniversity of S?o Paulo Division of Gastroenterology Department of MedicineRibeir?o Preto Medical SchoolUniversity of S?o Paulo Departamento de Química Laboratório de Pesquisas Forenses e Gen?micasFaculdade de FilosofiaCiências e Letras de Ribeir?o PretoUniversidade de S?o Paulo

BACKGROUND Patients with hepatitis C virus(HCV) and hepatocellular carcinoma(HCC) may or not develop iron overload(IO),which is associated with worst prognosis,because can cause serious damage to *** gene controls the iron uptake from gut,particularly in patients with hereditary hemochromatosis(HH).AIM To identify associations between HFE coding region in patients exhibiting hereditary hemochromatosis and in diseases associated with acquired *** We sequenced exons 2 to 5 and boundary introns of HFE gene,evaluating all polymorphic sites in patients presenting hereditary(hemochromatosis) or acquired iron overload HCV and HCC) and in healthy controls,using Sanger *** also determined the ensemble of extended haplotype in healthy control individuals,including several major histocompatibility complex loci,using sequence specific *** reconstruction was performed using the Arlequin and Phase softwares,and linkage disequilibrium(LD) between histocompatibility loci and HFE gene was performed using the Haploview *** The HFE*003 allele was overrepresented(f = 71%) and HFE*001 allele was underrepresented(f = 14%) in HH patients compared to all groups.A strong linkage disequilibrium was observed among the H63 D-G,IVS2(+4)-C and C282 YG gene variants,particularly in HH;however,the mutation IVS2(+4)T>C was not directly associated with HH *** HFE*001/HFE*002 genotype conferred susceptibility to HCC in HCV patients exhibiting IO(P = 0.02,OR =14.14).Although HFE is telomeric to other histocompatibility genes,the H63 DG/IVS2(+4)-C(P ≤ 0.00001/P ≤ 0.0057) combination was in LD with HLA-B*44 allele group in healthy *** LD was observed between HFE alleles and other major histocompatibility *** A differential HFE association was observed for HH and for diseases associated with acquired IO(HCV,HCC).Since HFE is very distant from other histocompatibility loci,only weak associations were observed with these a

关键词： HFE gene Hepatocellular carcinoma Hepatitis C Hemochromatosis hereditary Alleles Haplotypes