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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

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

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

Assessment of the Intertropical Convergence Zone over the Atlantic Ocean through an Algorithm Based on Precipitation

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Journal of Atmospheric Science Research 2024年第1期7卷 59-73页

作者： Natan Chrysostomo de Oliveira Nogueira pedro henrique Gomes Machado Michelle Simões Reboita André Luiz Reis Reis Natural Resources Institute Federal University of ItajubáItajubáMinas Gerais37500-903Brazil

The Intertropical Convergence Zone(ITCZ)is a key atmospheric system on a global scale,primarily driven by trade wind convergence near the *** ITCZ plays a crucial role in modulating the climate of the borders of tropical continental *** instance,Northeastern Brazil experiences a climate influenced by the ITCZ over the Atlantic *** some periods,the ITCZ exhibits double bands,known as the double *** the features of the ITCZ have been described using various approaches and atmospheric variables,there is still a lack of regional studies focusing on the ITCZ and double ITCZ in the Atlantic *** this context,the main goals of this study are(1)to describe a simple algorithm based on precipitation to identify the ITCZ and double ITCZ,(2)to present a climatology(1997-2022)of the position,width,and intensity of these two convective bands,and(3)to investigate variabilities in the ITCZ characteristics associated with anomalies of sea surface temperature(SST)in the tropical Pacific and Atlantic *** double ITCZ typically occurs southward of the main cloud band,and between February and April,both bands are more distant(~4.5°).In the western sector of the Atlantic Ocean,the ITCZ and its double band extend to more southerly latitudes in austral *** the entire Atlantic basin,the annual mean of the latitudinal position,width,and intensity of the ITCZ is 4.9°N,4.2°,and 11 mm/day,respectively,while for the double ITCZ,it is 0.4°N,2.6°,10.3 mm/day,*** the SST anomalies in the Pacific Ocean(El Niño and La Niña episodes)affect more the ITCZ width,the SST anomalies in the Tropical South Atlantic affect both its position and width.

关键词： Double ITCZ Precipitation Latitudinal position Northeastern Brazil Atlantic Ocean ENSO

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

Decomposition and stabilization of organic matter in an old-growth tropical riparian forest:effects of soil properties and vegetation structure

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Forest Ecosystems 2021年第1期8卷 173-181页

作者： pedro henrique de Godoy Fernandes Andréa Lúcia Teixeira de Souza Marcel Okamoto Tanaka Renata Sebastiani Graduate Program in Environmental Sciences Federal University of São CarlosSão CarlosSPBrazil Department of Environmental Sciences(DCAm) Federal University of São CarlosSão CarlosSPBrazil Department of Nature Mathematicsand Education SciencesFederal University of São CarlosSão CarlosSPBrazil

Background:Nutrient cycling in tropical forests has a large importance for primary productivity,and decomposition of litterfall is a major process influencing nutrient balance in forest *** large-scale factors strongly influence decomposition patterns,small-scale factors can have major influences,especially in old-growth forests that have high structural complexity and strong plant-soil *** we evaluated the effects of forest structure and soil properties on decomposition rates and stabilization of soil organic matter using the Tea Bag Index(TBI)in an old-growth riparian forest in southeastern *** data sets were described separately using Principal Components Analysis(PCA).The main axes for each analysis,together with soil physical properties(clay content and soil moisture),were used to construct structural equations models that evaluated the different parameters of the TBI,decomposition rates and stabilization *** best model was selected using Akaike’s ***:Forest structure and soil physical and chemical properties presented large variation among plots within the studied *** content was strongly correlated with soil moisture and the first PCA axis of soil chemical properties,and model selection indicated that clay content was a better predictor than this *** rates presented a large variation among tea bags(0.009 and 0.098 g·g^(−1)·d−1)and were positively related with forest structure,as characterized by higher basal area,tree density and larger *** stabilization factor varied between 0.211–0.426 and was related to forest stratification and soil clay ***:The old-growth forest studied presented high heterogeneity in both forest structure and soil properties at small spatial scales,that influenced decomposition processes and probably contributed to small-scale variation in nutrient *** rates were only influenced by forest structure,whereas the stabilizat

关键词： Tea bag index Forest structure Carbon fixation Nutrient cycling

Ambient Backscatter Communications over NOMA Downlink Channels

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China Communications 2020年第6期17卷 80-100页

作者： Weiyu Chen Haiyang Ding Shilian Wang Daniel Benevides daCosta Fengkui Gong pedro henrique Juliano Nardelli College of Electronic Science and Technology National University of Defense TechnologyChangsha 410073China College of Information and Communication National University of Defense TechnologyXi’an 710106China Department of Computer Engineering Federal University of CearáSobral 62010-560Brazil State Key Laboratory of Integrated Service Networks Xidian UniversityXi’an 710071China School of Energy Systems Lappeenranta University of TechnologyLappeenranta 53850Finland

In this paper,we investigate the performance of commensal ambient backscatter communications(AmBC)that ride on a non-ortho go nal multiple access(NOMA)downlink transmission,in which a backscatter device(BD)splits part of its received signals from the base station(BS)for energy harvesting,and backscatters the remaining received signals to transmit information to a cellular ***,under the power consumption constraint at BD and the peak transmit power constraint at BS,we derive the optimal reflection coefficient at BD,the optimal total transmit power at BS,and the optimal power allocation at BS for each transmission block to maximize the ergodic capacity of the ambient backscatter transmission on the premise of preserving the outage performance of the NOMA downlink ***,we consider a scenario where the BS is restricted by a maximum allowed average transmit power and the reflection coefficient at BD is fixed due to BD’s low-complexity *** algorithm is developed to determine the optimal total transmit power and power allocation at BS for this ***,a low-complexity algorithm is proposed for this scenario to reduce the computational complexity and the signaling ***,the performance of the derived solutions are studied and compared via numerical simulations.

关键词： power-domain NOMA ambient backscatter communications IoT wireless-powered devices optimization