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A remote sensing approach to estimate the load bearing capacity of soil

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Information Processing in Agriculture 2024年第1期11卷 109-116页

作者： Italo Rômulo Mendes de Souza Edson Eyji sano Renato paiva de Lima Anderson Rodrigo da Silva Statistics and Geoprocessing Laboratory Instituto Federal GoianoGeraldo Silva Nascimento RoadKm 2.575790-000 UrutaíGoiásBrazil Embrapa Cerrados BR-020 RoadKm 18Mailbox 0822373310-970 PlanaltinaDFBrazil department of Soil Science ‘Luiz de Queiroz’College of AgricultureUniversity of São PauloAv.Pádua Dias235-AgronomiaPiracicabaSP 13418-900Brazil

Preconsolidation pressure(σp)of soil can be considered as an indicator of the Load Bearing Capacity(LBC),which is the tolerated surface pressure before compaction,often caused by the traffic of agricultural *** this pioneering study,a remote sensing approach was introduced to estimate LBC throughσp from soils of the“Rio Preto”Hydrographic Basin,Bahia State,Brazil,in a monthly time lapse from 2016 to ***,σp is measured by a laborious and time demanding laboratory analysis,making it unfeasible to map large *** innovative methodology of this work consists of combining active–passive satellite data on soil moisture and pedotransfer functions of clay content and water matric potential to obtain geo-located estimates ofσ*** were analysed under different classes of soil use,land cover and slope;95%confidence intervals were built for the time series of mean values of LBC for each *** overall seasonal variation in LBC estimates is similar in areas with annual crops,grasslands and natural vegetation,and flat areas are less affected by soil moisture variations over the year(between seasons).LBC decreased,in general,at about 0.5%a year in flat ***,these areas demand attention,since they occupy 86%of the Basin and are mostly subjected to agricultural soil management and surface pressure by heavy machinery.

关键词： Soil compaction SMAP Preconsolidation stress Brazilian Cerrado

Channel Flows in Plate Heat Exchangers with the Aid of Particle Tracking Velocimetry

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Open Journal of Fluid Dynamics 2024年第3期14卷 163-183页

作者： Felipe José dos santos Leonel Edward Beckedorff Kleber Vieira de paiva Jorge luiz Goes oliveira PETROBRASPetrleo Brasileiro S.A. Rio de Janeiro Brazil Institute of Fluid Mechanics and Heat Transfer Technische Universitt Wien Vienna Austria department of Mobility Engineering Federal University of Santa Catarina Joinville Brazil

Channel flows of Plate Heat Exchangers (PHEs) were assessed by experiments with three different chevron angle arrangements in turbulent regime. Two chevron angles were selected to assess low and high pressure drop channels, besides a third mixed configuration as to achieve in-between results regarding hydraulic performance. Friction factor correlations were provided with the channel Reynolds number ranging from 1175 to 8325. Two-dimensional (2D) mean velocity field was obtained by Particle Tracking Velocimetry (PTV) with Reynolds number equal to 3450. To the best of our knowledge, this is the first experimental study that quantified the complete 2D velocity field of a typical PHE channel. This value allowed comparison with literature results of Plate and Shell Heat Exchanger (PSHE) channels with the same Reynolds number. PSHE mean velocity field is highly heterogeneous as compared to the one obtained for PHE channels. Peak velocity magnitude in the PSHE center is 50% higher than its bulk velocity, whereas this value is only 15% higher in the PHE center. Pressure drop in PHE mixed channels cannot be approximated by averaging chevron angles: furrow flow prevailed in the specified conditions. The axial velocity is asymmetric regarding the vertical plane. Smooth streamlines prevail in the channel inlet. Recirculation zones at the channel exit affect pipe flow in the manifold outlet with swirling flow structures. The necessary length to obtain fully developed pipe flow at the channel outlet was estimated. Significant velocity components occur in the distribution areas and can limit the heat exchanger performance. The results reported herein are essential to understand how the PHE channel geometry affects the velocity field and, therefore, local heat transfer and dissipation processes.

关键词： PHE PTV PSHE Friction Factor Chevron

RPLP0/TBP are the most stable reference genes for human dental pulp stem cells under osteogenic differentiation

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World Journal of Stem Cells 2024年第6期16卷 656-669页

作者： Daniel B Ferreira Leticia M Gasparoni Cristiane F Bronzeri Katiucia B S paiva Laboratory of Extracellular Matrix Biology and Cellular Interaction Department of AnatomyInstitute of Biomedical SciencesUniversity of São PauloSão Paulo 05508-000São PauloBrazil

BACKGROUND Validation of the reference gene(RG)stability during experimental analyses is essential for correct quantitative real-time polymerase chain reaction(RT-qPCR)data ***,in an unreliable way,several studies use genes involved in essential cellular functions[glyceraldehyde-3-phosphate dehydro-genase(GAPDH),18S rRNA,andβ-actin]without paying attention to whether they are suitable for such experimental conditions or the reason for choosing such ***,such studies use only one gene when Minimum Information for Publication of Quantitative Real-Time PCR Experiments guidelines recom-mend two or more *** impacts the credibility of these studies and causes dis-tortions in the gene expression *** tissue engineering,the accuracy of gene expression drives the best experimental or therapeutical *** cultivated DPSCs under two conditions:Undifferentiated and osteogenic dif-ferentiation,both for 35 *** evaluated the gene expression of 10 candidates for RGs[ribosomal protein,large,P0(RPLP0),TATA-binding protein(TBP),GAPDH,actin beta(ACTB),tubulin(TUB),aminolevulinic acid synthase 1(ALAS1),tyro-sine 3-monooxygenase/tryptophan 5-monooxygenase activation protein,zeta(YWHAZ),eukaryotic translational elongation factor 1 alpha(EF1a),succinate dehydrogenase complex,subunit A,flavoprotein(SDHA),and beta-2-micro-globulin(B2M)]every 7 d(1,7,14,21,28,and 35 d)by *** data were analysed by the four main algorithms,ΔCt method,geNorm,NormFinder,and BestKeeper and ranked by the RefFinder *** subdivided the samples into eight *** All of the data sets from clonogenic and osteogenic samples were analysed using the RefFinder *** final ranking showed RPLP0/TBP as the two most stable RGs and TUB/B2M as the two least stable *** theΔCt method or NormFinder analysis showed TBP/RPLP0 as the two most stable ***,geNorm analysis showed RPLP0/EF1αin the first *** algorithms’two least stab

关键词： dental pulp stem cells Reference gene Housekeeping gene Endogenous gene Osteogenic differentiation RefFinder

Floristic composition and edaphic relationships in ferruginous campo rupestre reference ecosystems

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Journal of Mountain Science 2024年第3期21卷 719-733页

作者： G.Wilson FERNANdeS Letícia RAMOS Dario C.paiva Jéssica CUNHA-BluM Vanessa Matos GOMES Daniel NEGREIROS Ecologia Evolutiva&Biodiversidade Departamento de GenéticaEcologia e Evolução/ICBUniversidade Federal de Minas Gerais31270-901Belo HorizonteMGBrazil Knowledge Center for Biodiversity 31270-901Belo HorizonteMGBrazil department of Biological Sciences Institute of EnvironmentFlorida International UniversityMiamiFL 33199USA Programa de Pós Graduação em Biodiversidade e Uso dos Recursos Naturais Universidade Estadual de Montes ClarosMontes ClarosMGBrazil Laboratório de Estudo das Relações Solo-Planta Departamento de SolosUniversidade Federal Rural do Rio de JaneiroSeropédicaRGBrazil

Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the *** environments with high economic relevance,such as the ferruginous campo rupestre(rupestrian grassland known as Canga in Brazil),are even more susceptible to severe impacts due to their extreme habitat conditions and low *** determination of reference ecosystems based on the intrinsic characteristics of the ecosystem is essential for conservation as well as to the implementation of ecological *** proposed the reference ecosystem of the three main types of habitats of the ferruginous campo rupestre based on their floristic *** described the floristic composition of each habitat and evaluated the physicochemical properties of the soils and the relationship between plants and *** three habitats showed high diversity of plant species and many endemic species,such as Chamaecrista choriophylla,Cuphea pseudovaccinium,Lychnophora pinaster,and Vellozia *** distribution of vegetation was strongly related with the edaphic characteristics,with a set of species more adapted to high concentration of base saturation,fine sand,organic carbon,and iron,while another set of species succeeded in more acidic soils with higher S and silt *** provide support for the contention that the ferruginous campo rupestre is a mosaic of different habitats shaped by intrinsic local *** to recognize the floristic composition of each particular habitat can lead to inappropriate restoration,increased habitat homogenization and increased loss of biodiversity and ecosystem *** study also advances the knowledge base for building the reference ecosystem for the different types of ferruginous campo rupestre habitats,as well as a key database for highlighting those species contribute most to community assembly in this diverse and threatened tropical mountain ecosystem.

关键词： Canga Ecological restoration Extreme ecosystem Non-forest ecosystems Rupestrian grassland Taxon environment relationships

Effects of Yerba Mate Consumption (Ilex paraguariensis) on Cardiac Remodeling in Rats

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Food and Nutrition Sciences 2024年第8期15卷 827-845页

作者： Carlos Eduardo Brochini de paiva Thaíssa Baptista Brochini de paiva Isabelle Tiburcio Pecin Ferreira sandra Cristina Genaro Danilo Silva Martins santos Thaoan Bruno Mariano Robson Chacon Castoldi Rafael Stuani Floriano Julia Amanda Rodrigues Fracasso lucas Pires Guarnier Marina Politi Okoshi Francis Lopes Pacagnelli Postgraduate Program in Health Sciences Unoeste Presidente Prudente Brazil Faculty of Medicine Unoeste Presidente Prudente Brazil department of Physiotherapy Unoeste Presidente Prudente Brazil department of Nutrition Unoeste Presidente Prudente Brazil Postgraduate Program in Science and Movement Unesp Rio Claro Brazil Postgraduate Program in Health Promotion University of Northern Paran (UNOPAR) Londrina Brazil School of dentistry So Paulo State University (UNESP) Araatuba Brazil department of Genetics Ribeiro Preto Medical School University of So Paulo USP Ribeiro Preto Brazil Internal Medicine department Botucatu Medical School So Paulo State University (UNESP) Botucatu Brazil

This study investigated the effects of yerba mate consumption, a South American beverage, on cardiac remodeling in rats. For this purpose, 24 male Wistar rats were divided into Control Group (CG) which received filtered water and a standard diet, and Yerba Mate Group (YM), 6 g of Ilex paraguariensis in 100 ml water and the same diet, for 30 days. The YM group showed a reduction in final body weight and food consumption without altering weight gain. Regarding cardiac remodeling, the YM group exhibited a decrease in the right ventricle weight/final body weight ratio, suggesting cardiac atrophy, without affecting the atria and left ventricle. There was no change in cardiomyocyte area or nuclear fractal dimension in both groups. However, animals that consumed yerba mate showed increased collagen deposition and a smaller fractal dimension in the left ventricle. The consumption of yerba mate at room temperature for 30 days induced changes in cardiac remodeling, as evidenced by increased collagen deposition and alterations in fractal dimension in the left ventricle.

关键词： Tereré Ilex paraguariensis Yerba Mate Cardiac Remodeling Fractal Dimension Hypertrophy

Evolution of the 3.65-2.58 Ga Mairi Gneiss Complex,Brazil:Implications for growth of the continental crust in the São Francisco Craton

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Geoscience Frontiers 2022年第5期13卷 110-128页

作者： Igor de Camargo Moreira Elson paiva oliveira Daniel Francisco Martins de Sousa Institute of Geosciences University of Campinas(UNICAMP)CampinasSPBrazil

The composition and formation of the Earth’s primitive continental crust and mantle differentiation are key issues to understand and reconstruct the geodynamic terrestrial evolution,especially during the ***,the scarcity of exposure to these rocks,the complexity of lithological relationships,and the high degree of superimposed deformation,especially with long-lived magmatism,make it difficult to study ancient *** this complexity,exposures of the Archean Mairi Gneiss Complex basement unit in the São Francisco Craton offer important information about the evolution of South America’s primitive ***,here we present field relationships,LA-ICP-SFMS zircon U-Pb ages,and LA-ICP-MCMS lu-Hf isotope data for the recently identified Eoarchean to Neoarchean gneisses of the Mairi *** Complex is composed of massive and banded gneisses with mafic members ranging from dioritic to tonalitic,and felsic members ranging from TTG(Tonalite-Trondhjemite-Granodiorite)to granitic *** new data point to several magmatic episodes in the formation of the Mairi Gneiss Complex:Eoarchean(ca.3.65–3.60 Ga),early Paleoarchean(ca.3.55–3.52 Ga),middle-late Paleoarchean(ca.3.49–3.33 Ga)and Neoarchean(ca.2.74–2.58 Ga),with no records of Mesoarchean ***-Hf data unveiled a progressive evolution of mantle differentiation and crustal recycling over *** the Eoarchean,rocks are probably formed by the interaction between the pre-existing crust and juvenile contribution from chondritic to weakly depleted mantle sources,whereas mantle depletion played a role in the Paleoarchean,followed by greater differentiation of the crust with thickening and recycling in the middle–late Paleoarchean.A different stage of crustal growth and recycling dominated the Neoarchean,probably owing to the thickening of the continental crust by collision,continental arc growth,and mantle differentiation.

关键词： São Francisco Craton Mairi Gneiss Complex Primitive continental crust Zircon U-Pb dating lu-Hf isotope geochemistry

Environmental parameters and tree physiology in two semiarid land use systems in Brazil

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Journal of Forestry Research 2019年第2期30卷 397-407页

作者： Marlete Moreira Mendes Ivanov Claudivan Feitosa de Lacerda Francisco Eden Fernandes paiva Ana Clara Rodrigues Cavalcante Teogenes Senna de oliveira departamento de Biologia Universidade Federal do Piaui departamento de Engenharia Agricola Campus do PiciUniversidade Federal do Ceara Embrapa Caprinos e Ovinos departamento de Solos Universidade Federal de Vicosa

To determine if reduced tree densities(number of trees per unit area) lead to changes in micro-meteorological and tree physiological characteristics, two areas with different tree densities were assessed. One was an agrosilvopastoral system(AGP) with low tree density, and the other, a secondary forest(SF) with greater tree numbers, both located in a semiarid region of Brazil. Data were collected simultaneously by two automated weather stations: rainfall, air(T_a) and soil temperatures(T_(s5 cm)), relative humidity(RHair), photosynthetically active radiation(PAR), soil moisture at two depths(M_(s30 cm)and M_(s50 cm)),and wind velocity(Vw). Net photosynthesis in Cordia oncocalyx Allema?o trees was measured with an infrared gas analyzer in February, March, May, July, August and September 2011, which encompasses a rainy period followed by a dry period. Average values of Ta, T_(s5 cm), Vwand PAR were greater and average values of RHairand M_(s50 cm) were lesser in the AGP. Photosynthetic rates were greater in plants growing under the AGP at the onset of the dry season when Vw, PAR and T_(s5 cm)were greater and M_(s50 cm) was lesser. Photosynthetic rates correlated strongly with physical parameters during the dry season, especially under SF. Differences in tree numbers between AGP and SF led to differences in physical environmental parameters;however, the latter had less influence on photosynthetic rates in C. oncocalyx during the rainy season. During the dry season, all physical parameters had an impact on net photosynthesis under SF but not under AGP. This indicates a certain independence of plants in AGP.

关键词： Agrosilvopastoral system Net photosynthesis Secondary forest Tree density

Regional validity of the parameters of a distributed runoff-erosion model in the semi-arid region of Brazil

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Science China(Technological Sciences) 2009年第11期52卷 3348-3356页

作者： SRINIVAsaN Vajapeyam Srirangachar paiva Fernanda Maria de Lima Federal University of Campina Grande Post-graduate programme in Civil and Environmental Engineering Campus I 58429-900 Campina Grande PB Brazil

The present paper examines the validity of the application of a distributed rainfall-runoff-erosion model on a regional basis in a semi-arid region of Brazil. The model tested is known as WESP (Water Erosion Simulation Program) developed by Lopes (1987). The model simulates the hydrograph and the sediment graph for individual events and thus, the model when properly calibrated can serve as a predictive tool for runoff and soil erosion on an individual or a continuous basis. The possibility of the existence of regionally applicable values for the parameters of the model WESP would be very interesting from the point of view of predictability of runoff and soil erosion from ungauged basins in the region. For this purpose, data collected in several experimental units in the experimental basin of Sumé as well as in the experimental basin of So Joo de Cariri have been used. The model was calibrated and validated in each of the experimental units (consisting of erosion plots and micro-basins) and the average value from all of the units for each of the parameters was considered to be the regional value. With these average values, all the events in all the experimental units were simulated. The results show that the runoff and erosion values simulated with this single parameter set were very good in all the units, being well within the acceptable deviations.

关键词： regional parameters model WESP experimental basins semi-arid region soil erosion

Landesman–Lazer Type Conditions and Multiplicity Results for Nonlinear Elliptic Problems with Neumann Boundary Values

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Acta Mathematica Sinica,English Series 2014年第2期30卷 229-250页

作者： Edcarlos Domingos DA SILVA Francisco Odair de paiva Universidade Federal de Gois Departamento de Matemtica Universidade Federal de So Carlos Departamento de Matemtica

We establish the existence and multiplicity of solutions for Steklov problems under non- resonance or resonance conditions using variational methods. In our main theorems, we consider a weighted eigenvalue problem of ... 详细信息

关键词： Neumann-Steklov eigenvalue problems resonance Landesman-Lazer conditions