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Global prevalence and gender inequalities in at least 60 min of self-reported moderate-to-vigorous physical activity 1 or more days per week:An analysis with 707,616 adolescents

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Journal of Sport and Health Science 2024年第5期13卷 709-716页

作者： Raphael H.O.araujo AndrúO.Werneck Clarice L.Martins Luciana L.Barboza Rafael M.Tassitano Nicolas Aguilar-Farias Gilmar M.Jesus Robinson Ramírez-véelez Riki Tesler Adewale L.Oyeyemi Ellen C.M.Silva Robert G.Weaver Mark S.Tremblay Javier Brazo-Sayavera Grégore I.Mielke Danilo R.P.Silva Graduation Program in Health Sciences Londrina State University(UEL)Londrina 86057-970Brazil Center for Epidemiological Research in Nutrition and Health Department of NutritionSchool of Public HealthUniversidade de Sao Paulo(USP)Sao Paulo 01246-904Brazil Department of Physical Education Federal University of ParaıbaParaıba 58051-900Brazil Research Centre of Physical Activity Health and LeisureFaculty of SportsLaboratory for Integrative and Translational Research in Population Health(ITR)University of PortoPorto 4500Portugal Postgraduate Program in Physical Education University of BrasıliaBrasılia 70910-900Brazil Department of Kinesiology and Community Health University of Illinois at Urbana-ChampaignChampaignIL 61801-3841USA Department of Physical Education Sports and RecreationUniversidad de La FronteraTemuco 4680000Chile Department of Health State University of Feira de SantanaFeira de Santana 44036-900Brazil Navarrabiomed Hospital Universitario de Navarra(HUN)Navarra Institute for Health Research(IdiSNA)Universidad Publica de Navarra(UPNA)Pamplona 31006Spain Facultad de Ciencias de la Educacion Unidad Central del Valle del Cauca(UCEVA)TuluaValle del Cauca 763022Colombia Health Management Department Faculty of Heath sciencesAriel UniversityAriel 40700Israel College of Health Solutions Arizona State UniversityPhoenixAZ 85004USA Arnold School of Public Health University of South CarolinaColumbiaSC 29208USA Healthy Active Living and Obesity Research Group Children’s Hospital of Eastern Ontario Research InstituteOttawaON K1H 8L1Canada Department of Pediatrics University of OttawaOttawaON K1H 8L1Canada Department of Health Sciences Carleton UniversityOttawaON K1S 5B6Canada Department of Sports and Computer Science Universidad Pablo de Olavide(UPO)Seville 41013Spain Centro Universitario Regional Noreste Universidad de la RepublicaRivera 40000Uruguay School of Public Health The University of QueenslandBrisbaneQLD 4006Australia Department of Physical Education

Background:Guidelines recommend that adolescents should accumulate an average of 60 min per day of moderate-to-vigorous physical activity(MvPA).However,using only this cut-off could hide important *** instance,from a population-level point of view,increasing physical activity for those with no or low physical activity could provide more health benefits than increasing physical activity for those with intermediate ***,including a more sensitive cut-point of≥1 days per week could be an additional strategy for identifying those with low access/opportunities for physical activity ***,the current study aims to estimate the prevalence of≥60 min of MvPA≥1 days per week among adolescents globally,and to describe any relevant gender ***:We used representative datasets from 146 countries/territories collected between 2003 and *** was *** were grouped into younger(≤14 years old)and older(>14 years old)*** Poisson regression models were used to identify the relative differences in≥60 min of MvPA≥1 days per week between boys and girls,and random-effects meta-analysis models were used to identify the pooled *** were stratified by country and ***:Approximately 80%of both younger and older adolescents reported≥60 min of MvPA≥1 days per *** prevalence was≥94%in Europe and Central Asia and North America,while the estimates for the other regions werevalence of≥60 min of MvPA≥1 days per week was higher among boys than girls,with the largest differences occurring among the oldest adolescents(Prevalence ratio_(≤14y)=1.04(95%confidence interval(95%CI)):1.03-1.04)*** ratio_(>14y)=1.09(95%CI:1.08-1.10)).Conclusion:Approximately 8 out of 10 adolescents reported accumulating≥60 min of MvPA≥1 days per week,with notable differences between *** differences were observed in several countries,especially among the oldest *** fo

关键词： Global School-based Student Health Survey Health Behaviour Among School-aged Children survey Inequality Surveillance Youth

Use of digital image analysis combined with fractal theory to determine particle morphology and surface texture of quartz sands

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第6期9卷 1131-1139页

作者： Georgia S.araujo Kátia v.Bicalho Fernando A.Tristao Federal Institute of Education Science and Technology of the State of Espírito SantoBrazil Department of Civil Engineering Federal University of Espírito SantoBrazil

The particle morphology and surface texture play a major role in influencing mechanical and hydraulic behaviors of sandy soils. This paper presents the use of digital image analysis combined with fractal theory as a tool to quantify the particle morphology and surface texture of two types of quartz sands widely used in the region of vitória, Espírito Santo, southeast of Brazil. The two investigated sands are sampled from different locations. The purpose of this paper is to present a simple, straightforward,reliable and reproducible methodology that can identify representative sandy soil texture *** test results of the soil samples of the two sands separated by sieving into six size fractions are presented and discussed. The main advantages of the adopted methodology are its simplicity, reliability of the results, and relatively low cost. The results show that sands from the coastal spit(BS) have a greater degree of roundness and a smoother surface texture than river sands(RS). The values obtained in the test are statistically analyzed, and again it is confirmed that the BS sand has a slightly greater degree of sphericity than that of the RS sand. Moreover, the RS sand with rough surface texture has larger specific surface area values than the similar BS sand, which agree with the obtained roughness fractal dimensions. The consistent experimental results demonstrate that image analysis combined with fractal theory is an accurate and efficient method to quantify the differences in particle morphology and surface texture of quartz sands.

关键词： Quartz sands Particle morphology and surface texture Image analysis Fractal theory

Geostatistics as a Methodology for Studying the Spatiotemporal Dynamics of Ramularia areola in Cotton Crops

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American Journal of Plant Sciences 2014年第15期5卷 2472-2479页

作者： Jaqueline A.Pizzato Dejania v.araujo Edineia A.S.Galvanin Jair Romano Júnior Andrea N.A.Matos Michelle vecchi Francieli D.Zavislak Center for Research Studies and Agro-Environmental Development(CPEDA)Mato Grosso State UniversityTangara da SerraBrazil Graduate Program in Environment and Agricultural Production Systems Mato Grosso State UniversityTangara da SerraBrazil Graduate Program in Environment and Agricultural Production Systems Mato Grosso State UniversityBarra BugresBrazil Biological Sciences Course Mato Grosso State UniversityTangara da SerraBrazil Agronomy Course Mato Grosso State UniversityTangara da SerraBrazil

Geostatistics as a methodology for studying the spatiotemporal dynamics of Ramularia areola in cotton crops. Geostatistics is a tool that has been used to study plant pathology, by modeling the spatiotemporal pattern of diseases, generating hypotheses about their epidemiological aspects in order to use tactics and strategies of rational control. The objective of this study was to use geostatistics to study the spatiotemporal dynamics of Ramularia areola in cotton crops. The experiment was conducted at the experimental area of Mato Grosso State University-Tangará da Serra campus, and arranged in a 2 × 3 factorial design, with randomized blocks, with two spaicngs (0.45 and 0.90 cm) and three conditions of soil coverage (no cover, P. glaucum and C. spectabilis). Geostatistical analysis of data was performed using data from temporal and spatial progress of R. areola, obtained through assessments of the incidence and severity of the disease in plants, and spatial dependence, and analyzed using semivariogram fittings. Through the isotropic exponential semivariogram model, it was possible to check the distribution pattern and spatial dependence of Ramularia leaf spot. Spatial dependence was observed for the disease—moderate to strong for most data evaluated. The pathogen spread from the primary source of inoculum, from the center portion towards the edges, forming foci originating from a source of secondary inoculum.

关键词： Ramularia areola Spatial Dependence Isotropic Exponential Semivariogram Kriging

Communities of saprobic fungi on leaf litter of vismia guianensis in remnants of the Brazilian Atlantic Forest

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Journal of Forestry Research 2017年第1期28卷 163-172页

作者： Loise araujo Costa Luís Fernando Pascholati Gusmao Laboratorio de Micologia Av Transnordestina Departamentode Ciências BiológicasUniversidade Estadual de Feira deSantanas/nNovo HorizonteFeira de SantanaBA 44031-460Brazil

We examined the mycobiota associated with vismia guianensis leaf litter in three Atlantic Forest remnants of Brazil＇ s semiarid region. Among the study sites, two remnants were protected forest reserves, whereas the third was influenced by major anthropogenic activities. Eighteen litter samples were collected in wet and dry seasons and were processed by particle filtration technique. A total of 4750 fungal isolates of 142 taxa were identified. Species richness was higher in litter samples collected during wet season. Nonmetric multidimensional scaling multivariate analysis showed differences in the composition of fungal communities among the sampling sites and the seasons. Analysis of similarity showed that the differences were statistically significant （R = 0.85; P = 0.0001）. Our findings revealed that spatial and temporal heterogeneity, and human activities had significant impacts on the saprobic fungi of v. guianensis leaf litter.

关键词： Biodiversity Conservation Seasonality Spatial heterogeneity Tropical fungi

在单级式光伏逆变器中应用1700v碳化硅开关器件的效益研究

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电力电子 2011年第4期9卷 19-22页

作者： Samuel v.araujo Christian Noding Benjamin Sahan Peter Zacharias 王剑黄海北京交通大学电气学院

在光伏电能变换系统中应用碳化硅(SiC)器件可以大幅降低成本,从而提高产品的竞争力。一方面开关频率的增加导致滤波元件变得更小,另一方面将最大系统电压增加到1500v可以消除在三相系统中的升压级。本文将在采用1700v碳化硅开关器件的... 详细信息

在光伏电能变换系统中应用碳化硅(SiC)器件可以大幅降低成本,从而提高产品的竞争力。一方面开关频率的增加导致滤波元件变得更小,另一方面将最大系统电压增加到1500v可以消除在三相系统中的升压级。本文将在采用1700v碳化硅开关器件的一个单级三相电路中探讨上述可能性。

关键词：光伏逆变器碳化硅开关器件

Contribution of inrush current to mechanical failure of power transformers windings

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High voltage 2019年第4期4卷 300-307页

作者： Rafael M.R.Barros Edson Gda Costa Jalberth F.araujo Filipe L.Mde Andrade Tarso v.Ferreira Department of Electrical Engineering Federal University of Campina GrandeAprigio Veloso St.882Campina GrandeBrazil

This work presents a study regarding the contribution of inrush current to the occurrence of mechanical fatigue in windings of a power transformer and,consequently,the impact of that phenomenon on the equipment's *** order to perform the study,electromagnetic transient simulations were used to determine the inrush current in a three-phase transformer ***,three-dimensional simulations,based on the finite element method,were performed to determine the electromechanical stresses in the equipment windings,under the effect of the inrush ***,the methods of critical plans and Palmgren–Miner were applied to perform the fatigue *** the results,the impact of inrush current on the integrity of the transformer's windings was determined,as well as,to estimate the reduction of lifespan of the equipment due to inrush *** number of inrushes needed for the total reduction of lifespan of the equipment due to mechanical fatigue was also *** results can be used in the transformers design stage,with the purpose of assisting the evaluation of mechanical withstand of equipment,which can minimise the possibility of failure and increase its lifespan.

关键词： winding fatigue power

On Second Order Degree of Graphs

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Acta Mathematica Sinica,English Series 2012年第1期28卷 171-182页

作者： Gabriela araujo-PARDO Camino BALBUENA Mika OLSEN Pilar vALENCIA Instituto de Matemáticas rea de la Investigación CientíficaUniversidad Nacional Autónoma de MxicoCircuito ExteriorCiudad UniversitariaCoyoacan04510 MxicoD.F.Mxico Departament de Matemàtica Aplicada III Universitat Politècnica de CatalunyaC/Jordi Girona 1-3(Edifici C2Despatx 302)08034-BarcelonaSpain Departamento de Matemáticas Aplicadas y Sistemas Universidad Autónoma MetropolitanaCalle Artificios 402o pisoCol.Hidalgo Delegación lvaro Obregón01120 Mxico D.F.Mxico

Given a vertex v of a graph G the second order degree of v denoted as d2（v） is defined as the number of vertices at distance 2 from v. In this paper we address the following question： What axe the sufficient conditions for a graph to have a vertex v such that d2（v） ≥ d（v）, where d（v） denotes the degree of v？ Among other results, every graph of minimum degree exactly 2, except four graphs, is shown to have a vertex of second order degree as large as its own degree. Moreover, every K4^--free graph or every maximal planar graph is shown to have a vertex v such that d2（v） ≥ d（v）. Other sufficient conditions on graphs for guaranteeing this property axe also proved.

关键词： Second order degree K4^-free graph planar graphs

Dynamical Demixing of a Binary Mixture Under Sedimentation

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Communications in Computational Physics 2023年第1期33卷 1-21页

作者： Andre S.Nunes Rodrigo C.v.Coelho vasco C.Braz Margarida M.Telo da Gama Nuno A.M.araujo Centro de F´ısica Te´orica e Computacional Faculdade de CiˆenciasUniversidade de LisboaP-1749-016 LisboaPortugal Departamento de F´ısica Faculdade de CienciasUniversidade de LisboaP-1749-016 LisboaPortugal Electric Ant Lab Science Park 1061098 XGAmsterdamThe Netherlands

We investigate the sedimentation dynamics of a binary mixture,the species of which differ by their Stokes coefficients but are identical *** analyze the sedimentation dynamics and the morphology of the final deposits using Brownian dynamics simulations for mixtures with a range of sedimentation velocities of both *** addition,we use the lattice Boltzmann method to study hydrodynamic *** found a threshold in the difference of the sedimentation velocities above which the species in the final deposit are *** degree of segregation increases with the difference in the Stokes coefficients or the sedimentation velocities above the *** propose a simple analytical model that captures the main features of the simulated deposits.

关键词： Sedimentation Brownian dynamics lattice Boltzmann method

Impact of Land Degradation on Soil Microbial Biomass and Activity in Northeast Brazil

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Pedosphere 2012年第1期22卷 88-95页

作者： J.S.NUNES A.S.F.araujo L.A.P.L.NUNES L.M.LIMA R.F.v.CARNEIRO A.A.C.SALvIANO S.M.TSAI Soil Quality Lab. Agricultural Science CenterFederal University of PiauíTeresinaPI(Brazil) Center of Nuclear Energy in Agriculture University of Sao PauloPiracicabaSP(Brazil)

Land degradation causes great changes in the soil biological *** process of degradation may decrease soil microbial biomass and consequently decrease soil microbial *** study was conducted out during 2009 and 2010 at the four sites of land under native vegetation(Nv),moderately degraded land(LDL),highly degraded land(HDL) and land under restoration for four years(RL) to evaluate changes in soil microbial biomass and activity in lands with different degradation levels in comparison with both land under native vegetation and land under restoration in Northeast *** samples were collected at 0-10 cm *** organic carbon(SOC),soil microbial biomass C(MBC) and N(MBN),soil respiration(SR),and hydrolysis of fluorescein diacetate(FDA) and dehydrogenase(DHA) activities were *** two years of evaluation,soil MBC,MBN,FDA and DHA had higher values in the Nv,followed by the *** decreases of soil microbial biomass and enzyme activities in the degraded lands were approximately 8-10 times as large as those found in the ***,after land restoration,the MBC and MBN increased approximately 5-fold and 2-fold,respectively,compared with the *** results showed that land degradation produced a strong decrease in soil microbial ***,land restoration may promote short-and long-term increases in soil microbial biomass.

关键词： land restoration microorganisms soil quality soil respiration