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The effectiveness of different wear indicators in quantifying wear on railway wheels of freight wagons

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Railway Engineering Science 2024年第3期32卷 307-323页

作者： Philipe Augusto de Paula Pacheco M.Magelli Matheus Valente Lopes pedro henrique alves Correa N.Zampieri N.Bosso Auteliano Antunes dos Santos Federal Institute of the Southeast of Minas Gerais(IF Sudeste MG) Técnico PanamáStreet 45Santos DumontMG 36246-311Brazil Railway Laboratory(Lafer) Universidade Estadual de Campinas(UNICAMP)Mendeleyev Street 200CampinasSP 13083-872Brazil Department of Mechanical and Aerospace Engineering Politecnico Di TorinoC.so Duca degli Abruzzi 2410129 TurinItaly

Railway infrastructure relies on the dynamic interaction between wheels and rails;thus,assessing wheel wear is a critical aspect of maintenance and *** paper focuses on the wheel-rail wear indicator T-gamma(Tγ).Amidst its use,it becomes apparent that Tγ,while valuable,fails to provide a comprehensive reflection of the actual material removal and actual contact format,which means that using only Tγas a target for optimization of profiles is not *** this work,three different freight wagons are evaluated:a meter-gauge and a broad-gauge heavy haul vehicles from South American railways,and a standard-gauge freight vehicle operated in Europe,with different axle loads and dissimilar new wheel/rail *** vehicles are subjected to comprehensive multibody simulations on various *** simulations aimed to elucidate the intricate relationship between different wear indicators:Tγ,wear index,material removal,and maximum wear depth,under diverse curves,non-compensated lateral accelerations(A_(nc)),and *** findings showed a correlation of 0.96 between Tγand wear depth and 0.82 between wear index and material removed for the outer *** the results,the Tγis better than the wear index to be used when analyzing wear depth while the wear index is more suited to foresee the material *** results also show the low influence of A_(nc)on wear index and Tγ.By considering these factors together,the study aims to improve the understanding of wheel-rail wear by selecting the best wear analysis approaches based on the effectiveness of each parameter.

关键词： Wear index Wear volume Wear modeling Dynamic simulation

Analysis of Perinatal Outcomes of Twin Pregnancy in a Referral Hospital for High Risk

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Open Journal of Obstetrics and Gynecology 2024年第7期14卷 983-995页

作者： Eduarda Paim pedro Lucas Carneiro ferreira Luciano Selistre Fernanda Grossi José Mauro Madi Gabriela Françoes Rostirolla Mdica Residente do Programa de Residncia em Ginecologia e Obstetrcia Hospital Geral de Caxias do Sul Rio Grande do Sul Brasil Faculdade de Medicina Universidade de Caxias do Sul Rio Grande do Sul Brasil Programa de Ps-Graduao Universidade de Caxias do Sul Rio Grande do Sul Brasil Servio de Ginecologia e Obstetrcia Hospital Geral de Caxias do Sul Rio Grande do Sul Brasil

Introduction: The incidence of twin pregnancies has increased significantly in recent decades. These pregnancies require more attention due to their worse outcomes than singleton pregnancies. Objective: To analyze the characteristics and perinatal outcomes of twin pregnancies at the Caxias do Sul General Hospital. Methods: This is a descriptive and retrospective study that included all births related to twin pregnancies between march 1998 and June 2018. Maternal and perinatal variables were analyzed. Descriptive analyses were carried out using measures of central tendency and dispersion for continuous variables (mean and standard deviation or median and interquartile range), according to a prior assessment of distribution using the Shapiro-Wilk test, and absolute (n) and relative (n%) frequencies for categorical variables. Results: 172 pairs of twins/21,972 births (0.8%) were identified. There was a high percentage of interpartum interval of less than 12 months, adherence and prenatal visits, body mass index, and need for neonatal intensive care. Stillbirth and neomortality rates were within acceptable parameters. Conclusion: The sample studied showed a percentage similar to that in the literature, a high rate of maternal and perinatal complications, characterizing it as a high-risk fetal pregnancy.

关键词： Pregnancy Twin Pregnancy High Risk Pregnancy Morbidity Perinatal Mortality Perinatal Results

Microstructural characterization and mechanical behavior analysis of 7075-T6 aluminum subjected to simulated lightning strikes

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Chinese Journal of Aeronautics 2021年第12期34卷 39-50页

作者： Luis henrique SANTOS Weslei Patrick Teodosio SOUSA Sara Silva ferreira DE DAFE pedro Americo Magalhaes JUNIOR Department of Mechanical Engineering Pontificia Universidade Catolica de Minas GeraisBelo Horizonte 30535-901Brazil

Aircrafts damages caused by lightning strikes have been known since the early days of ***,the physical effects on the aircraft structure are still being *** work seeks to evaluate the lightning strike effects in the aluminum alloy *** were submitted to lightning strike simulation in laboratory and the damages evaluated through characterization *** and profilometry tests have shown material loss to 0.272 mm depth in the damaged *** addition,it was detected the material accumulation occurrence in the damage vicinity of the *** the damage,it was found a region where metallurgical changes were *** tensile and microhardness tests results have shown reduction in the percentage elongation and hardness increasing in the material affected by *** results are corroborated by the X-Ray Diffraction(XRD)and Rietveld Method(red line)that indicated an increasing in dislocation density and micro-deformation in the material *** microscopy results have shown the presence of microcracks on the normal and cross-section surface of the samples *** Energy Dispersive X-Ray Spectroscopy(EDXS)and Electron Backscattered Diffraction Test(EBSD)found coarse intermetallic phases and precipitates compounds with dimensions greater than 1 lm in *** were responsible for nucleation of the microcracks that propagate along the material grain boundaries.

关键词： Aircraft structure Characterization techniques Lightning strikes Precipitates Microcracks

Biopolymers-based skin-interfaced triboelectric sensors

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Nano Research 2023年第9期16卷 11753-11782页

作者： Shujia Xu pedro henrique de Souza Barbosa Wenzhuo Wu School of Industrial Engineering Purdue UniversityWest LafayetteIN 47907USA Flex Laboratory Purdue UniversityWest LafayetteIN 47907USA Regenstrief Center for Healthcare Engineering Purdue UniversityWest LafayetteIN 47907USA Birck Nanotechnology Center Purdue UniversityWest LafayetteIN 47907USA The Center for Education and Research in Information Assurance and Security(CERIAS) Purdue UniversityWest LafayetteIN 47907USA

Rapid advances in artificial intelligence,robotics,and remote healthcare have increased the demand for sustainable and highperformance wearable *** devices are gaining traction due to their self-powered operation capability and potential as wearable energy ***-interfaced triboelectric sensors(SITSs)can detect various mechanical signals and monitor physiological signals in ***-based SITSs are ideal for skin-interfaced applications since they are biocompatible and *** review focuses on the recent advancements of SITS made from biocompatible polymer materials,such as plant-based,animal-based,and synthetic polymers,and highlights their potential for various applications,including human–machine interface(HMI)and physiological *** addition,the fundamentals,challenges,and prospects of SITS based on biocompatible polymers are discussed.

关键词： skin interfaced triboelectric sensors wearable devices biopolymers

Urbanization drives adaptive evolution in a Neotropical bird

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Current Zoology 2023年第5期69卷 607-619页

作者： Rilquer Mascarenhas pedro Milet Meirelles henrique Batalha-Filho National Institute of Science and Technology in Interdisciplinary and Transdisciplinary Studies in Ecology and Evolution(INCT IN-TREE) Instituto de BiologiaUniversidade Federal da Bahia40170-115 SalvadorBahiaBrazil

Urbanization has dramatic impacts on natural habitats and such changes may potentially drive local adaptation of urban *** change has been specifically shown to facilitate the fast adaptation of birds to changing environments,but few studies have investigated the genetic mechanisms of this *** investigations could provide insights into questions about both evolutionary theory and management of urban *** this study,we investigated whether local adaptation has occurred in urban populations of a Neotropical bird species,Coereba flaveola,specifically addressing whether observed behavioral adaptations are correlated to genetic signatures of natural *** answer this question,we sampled 24 individuals in urban and rural environments,and searched for selected loci through a genome-scan approach based on RADseq genomic data,generated and assembled using a reference genome for the *** recovered 46 loci as putative selection outliers,and 30 of them were identified as associated with biological processes possibly related to urban adaptation,such as the regulation of energetic metabolism,regulation of genetic expression,and changes in the immunological ***,genes involved in the development of the nervous system showed signatures of selection,suggesting a link between behavioral and genetic *** findings,in conjunction with similar results in previous studies,support the idea that cities provide a similar selective pressure on urban populations and that behavioral plasticity may be enhanced through genetic changes in urban populations.

关键词： behavioral adaptation phenotypic plasticity selection selective sweep South America

Anomalous behaviour detection using one-class support vector machine and remote sensing images: a case study of algal bloom occurrence in inland waters

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International Journal of Digital Earth 2021年第7期14卷 921-942页

作者： pedro henrique Moraes Ananias Rogério Galante Negri Graduate Program in Natural Disasters UNESP/CEMADENSão Josédos CamposSão PauloBrazil Sciences Technology Institute São Paulo State University(UNESP)São Josédos CamposSão PauloBrazil

algal blooms are a frequent subject in scientific discussions and are the focus of many recent studies,mainly due to their adverse effect on *** the lack of ground truth data and the need to develop tools for their detection and monitoring,this research proposes a novel method to automate *** derived from multi-temporal image series processing,spectral indices and classification with Oneclass Support Vector Machine(OC-SVM)are used in this *** from multi-spectral sensors on Landsat-8 and MODIS were acquired through the Google Earth Engine API(GEE API).In order to evaluate our method,two bloom detection case studies(Lake Erie(USA)and Lake Taihu(China))were *** were made with methods based on spectral index ***,to demonstrate the performance of the OC-SVM classifier compared to other machine learning methods,the proposal was adapted to be used with a Random Forest(RF)classifier,having its results added to the *** situ measurements show that the proposed method delivers highly accurate results compared to spectral index thresholding ***,a drawback of the proposal refers to its higher computational *** application of the new method to a real-world bloom case is demonstrated.

关键词： Remote sensing spectral indices unsupervised classification anomalies algal bloom detection

Lessons learnt from a deep excavation for future application of the observational method

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第3期10卷 468-485页

作者： Raul Fuentes Anton Pillai pedro ferreira School of Civil Engineering University of LeedsLeedsLS2 9JTUK Ove Arup and Partners 13 Fitzroy StreetLondonW1T 4BQUK Department of Civil Environmental&Geomatic EngineeringUniversity College LondonChadwick BuildingGower StreetLondonWC1E 6BTUK

This paper draws lessons learnt from a comprehensive case study in overconsolidated clay. Apart from the introduction of the case study, including field measurements, the paper draws on the observations and a three-dimensional（3 D） numerical analysis to discuss the implications of observations in the application of the observational method（OM） in the context of the requirements of EUROCODE 7（EC7）.In particular, we focus on corner effects and time-dependent movements and provide initial guidance on how these could be considered. Additionally, we present the validation of a new set of parameters to check that it provides a satisfactory compliance with EC7 as a set of design parameters. all these findings and recommendations are particularly important for those who want to use the OM in similar future projects.

关键词： Deep excavation Basement Ground movements Wall movements Retaining wall Corner effects Time-dependent movements

Effects of Imazethapyr-Based Herbicide Formulation in the Zebrafish (Danio rerio) Hepatocyte Cell Line (ZF-L): Cytotoxicity and Oxidative Stress

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Journal of Environmental Protection 2024年第6期15卷 747-765页

作者： Edila maria Kickhöfel Ferrer Milena Mattes Cerveira pedro henrique Flores Da Cruz Cleiton Jesus Andrade Pereira Lucas Moraes Berneira Claudio martin Pereira de Pereira Nathalia Stark Pedra Roselia maria Spanevello Jean Carlos Bauer Vieira Clarissa Piccinin Frizzo Mateus Tavares Kütter Janice Luehring Giongo Rodrigo de almeida Vaucher Center of Chemical Pharmaceutical and Food Sciences Microorganism Biochemistry and Molecular Biology Research Laboratory (LAPEBBIOM) Federal University of Pelotas (UFPEL) Pelotas Rio Grande do Sul Brazil Center of Chemical Pharmaceutical and Food Sciences Laboratory for Lipidomic and Bio-Organic Research Bioforensic Research Group Federal University of Pelotas (UFPEL) Pelotas Rio Grande do Sul Brazil Center of Chemical Pharmaceutical and Food Sciences Neurochemistry Inflammation and Cancer Laboratory Federal University of Pelotas (UFPEL) Pelotas Rio Grande do Sul Brazil Department of Chemistry Heterocycle Chemistry Center (NUQUIMHE) Federal University of Santa Maria (UFSM) Santa Maria Rio Grande do Sul Brazil Department of Microbiology and Parasitology Biology Institute Federal University of Pelotas (UFPEL) Pelotas Rio Grande do Sul Brazil

Seizures of agrochemical formulations have increased in Brazil and Rio Grande do Sul is among the Brazilian states with the highest number of seizures of these products obtained illicitly. The use of illicit formulations can cause significant harm to agricultural production, the environment, and non-target species. This study evaluated the cytotoxicity and oxidative stress of a seized formulation containing the herbicide imazethapyr (IMZT). Characterization of the herbicide included gas chromatography-mass spectrometry (GC-MS) and thermal analyses (thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC)). Hemolytic and cytotoxicity assays in ZF-L hepatic cells showed IC50 values of 12.75 µg/mL, 3.01 µg/mL, 2.67 µg/mL, and 1.61 µg/mL for erythrocytes, [3(4,5-dimethyl)-2 bromide-5 diphenyl tetrazolium] (MTT), neutral red (NR), and lactate dehydrogenase (LDH) assays, respectively. The median IC50 of 2.84 µg/mL was used in oxidative stress assays, revealing increased reactive oxygen species (ROS) production, reduced total sulfhydryl content, and decreased superoxide dismutase (SOD) and catalase (CAT) activity. This study is the first to report in vitro oxidative stress induced by IMZT in the ZF-L cell line, emphasizing the importance of in vitro assays for assessing the toxic effects of seized agrochemicals on human health and the environment.

关键词： Agrochemical Imidazolinone Zebrafish Cell Viability Oxidative Damage

Ecophysiology and multivariate analysis for production of Tachigali vulgaris in Brazil:Influence of rainfall seasonality and fertilization

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林业研究:英文版 2023年第5期34卷 1289-1305页

作者： pedro henrique Oliveira Simoes Candido ferreira de Oliveira Neto Manoel Tavares de Paula Dênmora Gomes de Araújo Rodrigo Silva do Vale Joao Olegário Pereira de Carvalho Universidade Federal de Mato Grosso Campus Universitario de SinopSinop 78550728Mato GrossoBrazil Universidade Federal Rural da Amazonia Campus BelemBelem 66077830ParaBrazil Universidade do Estado do Para Centro de Ciencias Naturais e TecnologiaBelem 66095015ParaBrazil Universidade Federal Rural da Amazonia Campus Capitao-PocoCapitao Poco 68650000ParaBrazil

Studies on fertilization management of species native to the Amazon for energy plantations contribute to the diversity of species use and reduce biological risk due to the excessive use of clones or hybrids of *** study evaluates the effect of precipitation seasonality and phosphorus and potassium fertilization on gas exchange in a Tachigali vulgaris *** levels of P(zero,65.2,130.4 kg ha^(-1))and three of K(zero,100.0,200.0 kg ha^(-1))were applied in a 3×3 factorial randomized block *** exchange measurements were conducted in April and November *** low rainfall,high irradiance period,photo synthetic rates were up to four times higher than in the high rainfall period,reaching 20.3μmol m^(-2)s^(-1)in the treatment with 130.4 g kg^(-1)of P and 100.0 g kg^(-1)of *** analysis and principal component analysis reduced the initial eight gas exchange variables to two and three principal components in periods of high and low rainfall,*** multivariate method used in this study readily identified variations in the variables as a function of rainfall,with high reliability in explaining the data set.

关键词： Photosynthesis rate Stomatal conductance Principal component analysis Factor analysis Tachigali vulgaris