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Computer Modeling in Engineering & Sciences 2018年第10期117卷 59-71页

作者： Guilherme Suguinoshita Carlos henrique da Silva Marco antonio Luersen Department of Mechanical Engineering Federal University of Technology-Parana(UTFPR)Rua Deputado Heitor Alencar Furtado5000CEP 81280-340CuritibaBrazil

This paper describes a study of the effects of graphite nodule characteristics on a subsurface crack in austempered ductile iron(ADI).A representative specimen of ADI,subjected to sliding contact load,is modeled using finite elements aiming to obtain the shear stress intensity factor(KII).The parameters varied were(i)the nodule diameter(two different values were considered),(ii)the distance between the nodule and the tip of the crack and(iii)the position of the load relative to the tip of the *** results of the numerical simulations show that the smaller diameter nodule has a larger influence on KII,suggesting a higher contact fatigue crack propagation rate in the material with the smaller *** results are the opposite of those observed in experimental studies and would appear to indicate that other factors should be also considered to ensure realistic estimates of the contact fatigue strength of ADI.

关键词： Austempered ductile iron subsurface crack stress intensity factor finite element analysis graphite nodule

A single session of strength training changed plasma levels of resistin,but not leptin in overweight and obese men

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Sports Medicine and Health Science 2024年第4期6卷 324-330页

作者： Yago Martins Fortes antonio Felipe Souza-Gomes Alessandro roberto Silveira Moreira Leo Nogueira Campos Samara Silva de Moura Lucelia Scarabeli Silva Barroso Marcelo henrique Salviano de Faria Heliana de Barros Fernandes Aline Silva de Miranda Hugo Cesar Martins-Costa Ana Cristina Simoes e Silva Janaina Matos Moreira Albena Nunes-Silva Laboratory of Inflammation and Exercise Immunology Department of Physical EducationSchool of Physical EducationFederal University of Ouro PretoOuro PretoMGBrazil Postgraduate Program in Health and Nutrition Nutrition SchoolFederal University of Ouro PretoOuro PretoMGBrazil Interdisciplinary Medical Research Laboratory Faculty of MedicineFederal University of Minas GeraisBelo HorizonteMGBrazil Neurobiology Laboratory Institute of Biological SciencesFederal University of Minas GeraisBelo HorizonteMGBrazil Department of Physical Education Pontifical Catholic University of Minas GeraisBrazil Department of Pediatrics Faculty of MedicineFederal University of Minas Gerais(UFMG)Belo HorizonteMGBrazil

Obesity has a complex multifactorial etiology and is characterized by excessive accumulation of adipose *** adipose tissue has deleterious effects on health because it secretes large amounts of inflammatory *** calorie restriction associated with strength training may be useful in managing chronic systemic *** study aimed to evaluate the acute effect of a single strength-training session on plasma adipokine levels in sedentary,overweight,and obese young *** study included twelve men(Age:[34.95±9.77]years;Height:[174.16±3.66]centimeter[cm];Weight:[97.83±12.87]kilogram(kg);body mass index[BMI]:[32.30±4.51]kg/m2),who performed a single strength training *** strength training protocol consisted of 4 sets of 12 repetitions in the following six exercises,45°leg press,bench press,leg extension,machine row,leg curl,and shoulder *** samples were collected before,immediately after,and 1-h subsequent after strength *** plasma levels of resistin and leptin were measured.A significant decrease in resistin levels were found 1 h after the strength training session if compared to levels before the training session(pre-[before][2390±1199]picograms per milliliter[pg/mL]vs post-1 h[1-h subsequent][1523±798],6 pg/mL,p=0.0028).The plasma leptin levels did not differ at any time *** conclusion,a very well controlled single session of strength training significantly decreased the plasma levels of resistin without altering the concentration of leptin in overweight and obese *** effect,at least in part,supports the benefits of exercise by reducing the low grade inflammation and insulin resistance in obesity.

关键词： Strength training Adipose tissue Obesity Chronicinflammation Resistin Leptin

A Bidimensional Finite Element Study of Crack Propagation in Austempered Ductile Iron

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Computers, Materials & Continua 2023年第11期77卷 1411-1424页

作者： Gustavo von Zeska de França roberto Luís de Assumpção Marco antonio Luersen Carlos henrique da Silva Department of Mechanical Engineering Federal University of Technology–ParanáCuritiba81280-340Brazil

Austempered ductile iron(ADI)is composed of an ausferritic matrix with graphite nodules and has a wide range of applications because of its high mechanical strength,fatigue resistance,and wear resistance compared to other cast *** amount and size of the nodules can be controlled by the chemical composition and austenitizing *** the nodules have lower stiffness than the matrix and can act as stress concentrators,they influence crack ***,the crack propagation mechanism in ADI is not yet fully *** this study,we describe a numerical investigation of crack propagation in ADIs subjected to cyclic *** numerical model used to calculate the stress intensity factors in the material under the given conditions is built with the aid of Abaqus commercial finite element *** crack propagation routine,which is based on the Paris law,is implemented in *** results of the simulation show that the presence of a nodule generates a shear load on the crack ***,even under uniaxial tensile loading,the presence of the nodule yields a non-zero stress intensity factor in mode II,resulting in a deviation in the crack propagation *** is the primary factor responsible for changing the crack propagation direction towards the *** the parameters,for example,increasing the nodule size or decreasing the distance between the nodule and crack tip,can intensify this *** simulations comparing two different ADIs with the same graphite fraction area,the crack in the material with more nodules reaches another nodule in a shorter propagation time(or shorter number of cycles).This suggests that the high fatigue resistance observed in ADIs may be correlated with the number of nodules intercepted by a crack and the additional energy required to nucleate new *** summary,these findings contribute to a better understanding of crack propagation in ADIs,provide insights into the relationship between the presence

关键词： Austempered ductile iron(ADI) fatigue crack propagation graphite nodule

Paleo-and Mesoarchean TTG-sanukitoid to high-K granite cycles in the southern São Francisco craton,SE Brazil

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Geoscience Frontiers 2022年第5期13卷 153-168页

作者： Claudio de Morisson Valeriano Caio Vinicius Gabrig Turbay henrique Bruno antonio Simonetti Monica Heilbron Samuel Moreira Bersan rob Strachan Universidade do Estado do Rio de Janeiro Faculdade de GeologiaRua São Francisco Xavier 524/4006-BMaracanãRio de JaneiroBrazil Universidade Federal do Sul da Bahia Centro de Formação em Ciências AmbientaisPorto SeguroBahiaBrazil University of Portsmouth School of EnvironmentGeography and GeosciencesBurnaby BuildingBurnaby RoadPortsmouth PO13QLUnited Kingdom University of Notre dame Department of Civil and Environmental Engineering and Earth Sciences46556United States

The generation of the continental crust is widely accepted to have taken place predominantly in the Archean,when TTG magmatism associated with greenstone-belt supracrustal succession development was typically followed by emplacement of high-K granites before crustal *** study focuses on the Campos Gerais complex(CGC),which is an Archean granite-greenstone belt lithological association in a tectonic window located in the southwesternmost portion of the São Francisco craton(SFC).The CGC is an important segment of Paleo-to Mesoarchean continental crust to be integrated into paleogeographic reconstructions prior to the transition into the *** investigation reports field relationships,28 major and trace element compositions,U–Pb(zircon)geochronological results,and Hf and Sm–Nd isotope data for orthogneiss and amphibolite *** results indicate that the CGC records a complex Archean crustal evolution,where voluminous 2.97 Ga TTG tonalites and trondhjemites(ε_(Nd)(t)=-4.7;T_(DM)=3.24 Ga)were followed by 2.89 Ga sanukitoid tonalite production(ε_(Nd)(t)=-1.9;T_(DM)=3.02 Ga),broadly coeval with the development of the Fortaleza de Minas and Pitangui *** events are interpreted to represent the initial stage of an important subduction-accretion tectonic cycle,which ended with the emplacement of 2.82–2.81 Ga high-K leucogranites and migmatization of the TTG-sanukitoid crust,with hybrid and two-mica,peraluminous compositions(ε_(Nd)(t)=-8.0 to-8.6;T_(DM)=3.57–3.34 Ga).The presence of inherited zircons with207Pb/206Pb ages of 3.08 Ga,3.29 Ga,3.55 Ga and 3.62 Ga indicates that the Mesoarchean tectonic processes involved reworking of Meso-to Eo-archean *** TTG magmatism took place at ca.2.77 Ga represented by juvenile tonalite stocks(ε_(Nd)(t)=+1.0 to-1.5;T_(DM)=2.80–2.88 Ga)which intrude the TTG-greenstone belt *** stabilization was attained by 2.67 Ga,allowing for the emplacement of within-plate thol

关键词： Crustal evolution Sm–Nd Lu–Hf LA-ICPMS zircon U–Pb

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Evaluation of Porous Structure of Cement Pastes Made with Residual Rice Husk Ash

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Journal of Civil Engineering and Architecture 2014年第11期8卷 1396-1402页

作者： Joao henrique da Silva Rego antonio Alberto Nepomucenol Enio Pazini Figueiredo Nicole Pagan Hasparyk Department of Environmental and Civil Engineering University of Brasilia Brasilia/DF 70910-900 Brazil School of Civil Engeneering Federal University of Goi6s Goidnia/GO 74605-22 Brazil Department of Technical Support and Control Furnas Centrals Eldtricas Aparecida de Goidnia/GO 74001-970 Brazil

In several countries, the residual RHA （rice husk ash） has been produced in rice processing industries or in thermoelectric plants that use rice husk to generate heat and/or electrical energy, usually without burning process control. This causes a reduction in the amorphous silica content of residual RHA, which distinguishes them from the RHA produced according to controlled burning process, which is totally amorphous and considered a highly reactive pozzolan. In this paper, the hydration products and the porous structure of binders paste were studied by replacing, in weight of 5%, 10% and 20% of Portland cement OPC （ordinary Portland cement）, by residual RHAs named A and B, which have high and low content of amorphous silica, respectively, using microstructure evaluation techniques as XRD （X-ray diffraction）, TG （thermogravimetric） tests and MIP （mercury intrusion porosimetry）. A reducing the size of the pores of the pastes was observed according to the increase of content replacement of RHA A and RHA B.

关键词： Mineral addition residual rice husk ash pozzolanic activity porous structure microstructure.

Trans-10,cis-12 conjugated linoleic acid reduces neutral lipid content and may affect cryotolerance of in vitro-produced crossbred bovine embryos

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Journal of Animal Science and Biotechnology 2014年第4期5卷 391-398页

作者： Ribrio Ivan Tavares Pereira Batista Nadia Rezende Barbosa Raposo Paulo henrique Almeida Campos-Junior Michele Munk Pereira Luiz Sergio Almeida Camargo Bruno Campos Carvalho Marco antonio Sundfeld Gama Joao henrique Moreira Viana Federal University of Juiz de Fora Juiz de ForaMG 36036-900Brazil Embrapa dairy Cattle Research Center Juiz de ForaMG 36038-330Brazil Federal University of Minas Gerais Belo HorizonteMG 31270-901Brazil

Background：Due to high neutral lipids accumulation in the cytoplasm,in vitro-produced embryos from Bos primigenius indicus and their crosses are more sensitive to chilling and cryopreservation than those from Bos primigenius *** objective of the present study was to evaluate the effects of trans-10,cis-12 conjugated linoleic acid（CLA） on the development and cryotolerance of crossbred Bos primigenius taurus x Bos primigenius indicus embryos produced in vitro,and cultured in the presence of fetal calf *** zygotes（n = 1,692）were randomly assigned to one of the following treatment groups：1） Control,zygotes cultured in Charles rosenkrans 2 amino acid（CR2aa） medium（n = 815） or 2） CLA,zygotes cultured in CR2 aa medium supplemented with 100 μmol/L of trans-10,cis-12 CLA（n =877）.Embryo development（cleavage and blastocyst rates evaluated at days 3 and 8 of culture,respectively）,lipid content at morula stage（day 5） and blastocyst cryotolerance（re-expansion and hatching rates,evaluated 24 and 72 h post-thawing,respectively） were compared between ***,selected mRNA transcripts were measured by Real-Time PCR in blastocyst ***：The CLA treatment had no effect on cleavage and blastocyst rates,or on mRNA levels for genes related to cellular stress and *** the other hand,abundance of mRNA for the 1-acylglycerol-3-phosphate0-acyltransferase-encoding gene（AGPAT）,which is involved in triglycerides synthesis,and consequently neutral lipid content,were reduced by CLA treatment.A significant increase was observed in the re-expansion rate of embryos cultured with trans-10,cis-12 CLA when compared to control（56.3 vs.34.4%,respectively,P = 0.002）.However,this difference was not observed in the hatching rate（16.5 vs.14.0%,respectively,P=0.62）.Conclusions：The supplementation with trans-10,ds-12 CLA isomer in culture medium reduced the lipid content of in vitro produced bovine embryos by reducing the gene expression of 1-acylglycerol 3-phosphate 0

关键词： Blastocysts CLA Crossbred cattle Cryopreservation Lipid content

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Hydrodynamics and suspended particulate matter retention in macrotidal estuaries located in Amazonia-semiarid interface(Northeastern-Brazil)

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International Journal of Sediment Research 2020年第4期35卷 417-429页

作者： Vinicius henrique Maciel dos Santos Francisco Jose da Silva Dias Audalio Rebelo Torres romulo Araujo Soares Lais Costa Terto antonio Carlos Leal de Castro Ricardo Luvizotto Santos Marco Valerio Jansen Cutrim Laboratorio de Hidrodinamica Costeira Estuarina e de Aguas Interiores (LHiCEAI) Do Programa de Pos-Graduacao Em Oceanografia (PPGOceano) da Universidade Federal Do Maranhao (UFMA)Cidade Universitaria Dom Delgado Laboratorio de Ictiologia (LabIctio) da Universidade Federal Do Maranhao (UFMA) Cidade Universitaria Dom Delgado Laboratorio de Ecotoxicologia (LabEcotox) Do Programa de Pos-Graduacao Em Oceanografia (PPGOceano) da Universidade Federal Do Maranhao (UFMA) Cidade Universitaria Dom Delgado Laboratorio de Ficologia (LabFic) Do Programa de Pos-Graduacao Em Oceanografia (PPGOceano) da Universidade Federal Do Maranhao (UFMA) Cidade Universitaria Dom Delgado

The aim of the current study was to determine the nature of the seasonal variability of the Suspended Particulate Matter(SPM) fluxes from the drainage basin to the estuary in a macrotidal region(Northeastern Brazil),and the estuarine response to a seawater intrusion regarding sediment deposition,which will support the understanding of the global transport of materials at the continent-ocean *** structure data was acquired using a Conductivity,Temperature,and Depth(CTD) probe with a sampling frequency of 4 *** particulate material was measured by gravimetric measurements applied to exact filtered volume *** outflows were measured through the use of an Acoustic Doppler Current Profiler(ADCP) with frequency of 1.5 *** horizontal thermal and saline gradients varied from warmer and less saline waters(2014) to cooler and saline waters(2015).The gradient behavior when linked to volume transport and SPM flows,suggests a minimization of the fluvial flows in 2015,easing the advance of coastal water(CW) towards the inner estuary,leading to an inversion of the baroclinic pressure *** bottom saline front,generated by the entrance of coastal water masses,caused an increase in SPM concentrations due to increased fluid density,resuspension of previously deposited sediment,and erosion of *** concentrations of SPM indicate higher volume transport suggesting a hydraulic barrier due to the change/inversion of the baroclinic pressure gradient,resulting in water and material *** deposition was observed during neap tide,while during spring tide the material is resuspended,increasing the concentration,generating cycles of deposition and erosion during the neap-spring *** sediment in suspension that reach the estuary,even with low fluvial volume,stay in this environment forming new islands because of *** deposition rates or sediment cycling,if generated by the hydraulic barrier,may indicate that the flo

关键词： Brazilian Amazonia Materials discharges Macrotidal estuaries Freshwater percentage Residence time

Use of ANSYS for Thermal Analysis in Mass Concrete

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Journal of Civil Engineering and Architecture 2014年第7期8卷 860-868页

作者： Nailde de Amorim Coelho Lineu Jose Pedroso Joao henrique da Silva Rego antonio Alberto Nepomuceno Department of Civil and Environment Engineering University of Brasilia Brasilia 70.919-970 Brazil

With the increasing development of Brazil in recent years, major engineering construction works have been designed and built, partieutarly those involving large volumes of mass concrete, such as in the case of dams. Mass concrete, due to its large size and volume, presents a considerable temperature rise caused by cement grain hydration. This temperature rise can be sufficient to cause concrete crack and/or cracking, which may lead to serious problems. In this paper, we sought to study heat generation and temperature field in mass concrete through ANSYS software, which uses finite element method to analyze the problem. This program allows temperatures to be checked for different concrete ages. With that, it is possible to evaluate the temperatures obtained and the factors influencing the results in a short period of time at a low cost. With the help of the software, it is possible to check the temperatures for different concrete properties by analyzing them on different concreting days. Therefore, it was possible to establish that the properties of the concrete directly influence the temperature evolution phenomenon.

关键词： Temperature mass concrete isotherms numerical analysis.

Polyphenolic composition, antibacterial, modulator and neuroprotective activity of Tarenaya spinosa(Jacq.) Raf.(Cleomaceae)

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Asian Pacific Journal of Tropical Biomedicine 2019年第1期9卷 12-17页

作者： Francisca Samara Muniz dos Santos Jose Weverton Almeida Bezerra Jean Paul Kamdem Aline Augusti Boligon Marli Matiko Anraku Ana Raquel Pereira da Silva Kleber Ribeiro Fidelis Nadghia Figueiredo Leite antonio Ivanildo Pinho henrique Douglas Melo Coutinho Jose Edilson Goncalves dos Santos Microscopy Laboratory Regional University of Cariri (URCA) Program Post graduate in Plant Biology (UFPE) Phytochemical Laboratory Department of Industrial Pharmacy Federal University of Santa Maria (UFSM) Microbiology and Molecular Biology Laboratory Regional University of Cariri (URCA)

Objective: To evaluate the antibacterial activity and neuroprotective capacity of the ethanolic and aqueous extracts of Tarenaya spinosa(T. spinosa) as well as to determine and quantify some of its polyphenols by high performance liquid chromatography with diode-array detection(HPLC-daD). Methods: The bacterial Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa strains, grown in Heart Agar Infusion, were tested. The drugs gentamicin, norfloxacin and imipenem were used to evaluate the modulating or antagonistic capacity of the T. spinosa extracts. The extract was analysed by HPLC-daD to determine the main phenolic compounds. For the cell viability tests, individual heads of the Nauphoeta cinerea arthropod model were removed, homogenized in Trifluoromethyl ketone and centrifuged afterwards. Subsequently, 20 μL of NaN O2 were added to the biological material, except in the control group, to evaluate the protection capacity of the extracts. The homogenate of the insect heads was incubated for 2 h in tubes containing tetrazolium bromide. Results: HPLC-daD demonstrated that the ethanolic extract of T. spinosa presented caffeic acid as the major compound. The ethanolic extract also showed neuroprotective effects at concentrations ≥ 10 μg/mL, while aqueous extract was shown to have a protective effect only at the concentration of 100 μg/mL. The aqueous extract demonstrated a clinically relevant antibacterial activity against the Staphylococcus aureus multidrug resistant strain-MDR, with MIC 512 μg/m L. However, when the extracts were associated with gentamicin and imipenem, a synergism was detected against Staphylococcus aureus and Escherichia coli MDR strains. Conclusions: Although it does not present an antibacterial action, the extracts of T. spinosa can be used in the pharmaceutical industries since its extracts show modulating action of drugs. Besides, these natural products have neuroprotective capacity.

关键词： Tarenaya spinosa Cleome spinose Nauphoeta cinerea Synergism Antibiotic resistance

Autoregressive spatial analysis and individual tree modeling as strategies for the management of Eremanthus erythropappus

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Journal of Forestry Research 2016年第3期27卷 595-603页

作者： henrique Ferraco Scolforo Jose roberto Soares Scolforo Jose Marcio de Mello Anto nio Carlos Ferraz Filho Diogo Francisco rossoni Thiza Falqueto Altoe antonio Donizette Oliveira Renato Ribeiro de Lima Department of Forest Science Federal University of Lavras PO Box: 3037 Lavras MG 37200-000 Brazil Department of Statistics State University of Maringa Av. Colombo 5.790 Jd. Universitario Bloco E90 Maringa PR 87020-900 Brazil Department of Statistics Federal University of Lavras PO Box: 3037 Lavras MG 37200-000 Brazil

The objectives of this study were to apply statistical techniques to discriminate fertilization treatments of Eremanthus erythropappus（DC.） Mac *** autoregressive modeling, and to develop individual tree models for diameter and crown area（CA） projection to define management strategies for candeia plantations subjected to different fertilization treatments. This is an important tree species originating from the Brazilian Atlantic Rain forest and Savannah biomes, intensively used in the cosmetic industry. Nonetheless, to date, research has not addressed the management of natural stands or plantations of the species. Our experiment was located in Baependi, Minas Gerais, Brazil, and comprised of four randomized blocks and 13 treatments. The treatments consisted of 12 different regimes of fertilization plus a control. Each sample plot was composed of 50 plants plus two border plants in a planting spacing of 2.5 9 2.0 m and undergoing pruning at 5 and 6 years of age. Starting in the second year, total tree height（H） and circumference（at 1.30 m from the ground or breast height, CBH） were measured every 6 months. Starting in the fifth year CA was measured. Tree growth varied by fertilization *** were detected by using an autoregressive approach, considering that standard statistical methods were not powerful enough to detect significant *** growth groups were formed, and maximum growth was obtained for treatment 10（NPK, 8-28-16）. Management guidelines are provided based on individual tree models for different fertilization levels.

关键词： Management strategies Candeia Fertilization level Brazil Crown area

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