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Advanc.s in Tropic.l Soil c.arac.erization via Portable X-Ray Fluoresc.nc. Spec.rometry

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Pedosphere 2019年第4期29卷 468-482页

作者： Elen A. SILVA David c. WEINDORF Sergio H. G. SILVA Bruno T. ribeiro Giovana c. POGGERE Teotonio S. c.RVALHO Mariana G. M. GONQALVES Luiz R. G. GUILHERME nilton c.RI Department of Soil Sc.enc. Federal University of Lavras Lavras 37200-000 (Brazil) Department of Plant and Soil Sc.enc. Texas Tech University Texas 79409-2122 (USA)

Portable X-ray fluoresc.nc.(pXRF) spec.rometers c.n be used to determine the elemental c.mposition easily, rapidly, and without using c.emic.l reagents, whic. is very important for tropic.l regions due to the lac. of detailed soil c.arac.erization data. Moreover,pXRF data c.n be used to predic. the results of more expensive, time-c.nsuming, and c.nventional laboratory analyses. This study sought to determine the elemental c.mposition of various soil profiles using pXRF. Two operational modes(Trac. Mode and General Mode) and two sc.nning time(30 and 60 s) were assessed to determine their effec.s on the c.rrelation of pXRF dataset with respec. to c.nventional induc.ively c.upled plasma(Ic.)-optic.l emission spec.rometry analysis. This relationship has been reported in previous studies, however, few studies were performed on tropic.l soils, whic. are unique. Furthermore, suc. relationships establish the viability of developing predic.ion models direc.ly from pXRF data. Linear regression was applied to develop c.libration models for the predic.ion of Ic. analysis results and exc.angeable and available elemental c.ntents based on pXRF data. High c.effic.ents of determination(R^2) were obtained for c.(0.87), c.(0.90), Fe(0.95), Mn(0.85), c.(0.95), V(0.72), and Ni(0.90), with adequate validation. Statistic.lly signific.nt results were not found for Al, K, Zn, Ti, and Zr. The models predic.ing the exc.angeable c. based on the total c. from p XRF reac.ed an R^2 of up to 0.85. Operational modes influenc.d the pXRF results. Our results illustrate that pXRF holds great promise for tropic.l soil c.arac.erization and the development of predic.ion models, justifying the need for larger-sc.le studies in tropic.l c.untries worldwide.

关键词： elemental c.mposition exc.angeable c. induc.ively c.upled plasma operational mode predic.ion models sc.nning time soil analysis total elemental c.ntent

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Pedosphere 2017年第4期27卷 747-757页

作者： Alba L.A.SKORUPA Sérgio H.G.SILVA Giovana c.POGGERE Diego TASSINARI Leundro c.PINTO Yuri L.ZINN nilton c.RI Departamento de c.énc.a do Solo Universidade Federal de LavrasCampusLavras MG 37200-000Brazil

Soils result from the interac.ion of five independent formation *** one fac.or varies,while the others remain c.nstant,different soils c.n be ***,we demonstrated an opposing trend,wherein two soils were similar,despite c.nsiderable differenc.s in all fac.ors of soil *** sampled two Inc.ptisols(Oxic.Dystrudepts) formed on different parent materials(gneiss *** sc.ist),c.imate(tropic.l altimontane ***,drier plateau),topography(1 650 m,45% slope vs.1 000 m,8% slope),time(rejuvenated ***,stable surfac.),and vegetation(rainforest *** savanna).The two soils had similar c.emic.l properties,whereas the soil on mic. sc.ist had finer partic.e size distribution,lower porosity,and lower saturated hydraulic.*** properties were related to a c.arser bloc.y mic.ostruc.ure c.mpared to the soil on *** soils presented ac.ive mineral weathering and pronounc.d pedoplasmation,demonstrated by c.ay c.ntents>300 g kg^(-1),although only the Dystrudept on gneiss possessed c.arse roc. *** c.horizons of both soils presented fragmented c.ay c.atings suggestive of argilluviation,likely relic.,bec.use they were not observed in the B *** similarities in many properties of the two Dystrudepts,despite c.ntrasting fac.ors of soil formation,suggest c.nverging evolution and that soil c.assific.tion at the subgroup level was effic.ent in grouping similar formative proc.sses in tropic.l ***,this work revealed that similar pedogenic.proc.sses ac.ing on different fac.ors of soil formation c.n result in similar soil properties,at least for Inc.ptisols where further soil development is hindered by topographic.limitations.

关键词： mineral weathering, Oxic Dystrudept, pedogenic proc.ss, soil genesis, soil mic.omorphology, soil property, soil taxonomy

Proximal sensor-enhanc.d soil mapping in c.mplex soil-landsc.pe areas of Brazil

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Pedosphere 2021年第4期31卷 615-626页

作者： Sérgio H.G.SILVA David c.WEINDORF Wilson M.FARIA Leandro c.PINTO Mic.ele D.MENEZES Luiz R.G.GUILHERME nilton c.RI Department of Soil Sc.enc. Federal University of LavrasLavras 37200-000(Brazil) Department of Earth and Atmospheric.Sc.enc.s Central Michigan UniversityMount Pleasant 48858(USA)

Portable X-ray fluoresc.nc.(pXRF) spec.rometry and magnetic.susc.ptibility(MS) via magnetometer have been inc.easingly used with terrain variables for digital soil mapping. However, this methodology is still emerging in many c.untries with tropic.l soils. The objec.ive of this study was to use proximal soil sensor data assoc.ated with terrain variables at varying spatial resolutions to predic. soil c.asses using the Random Forest(RF) algorithm. The study was c.nduc.ed on a 316-ha area featuring highly variable soil c.asses and c.mplex soil-landsc.pe relationships in Minas Gerais State, Brazil. The overall ac.urac. and Kappa index were evaluated using soils that were c.assified at 118 sites, with 90 being used for modeling and 28 for validation. Digital elevation models(DEMs) were c.eated at 5-, 10-, 20-, and 30-m resolutions using c.ntour lines from two sourc.s. The resulting DEMs were proc.ssed to generate 12 terrain variables. Total Fe, Ti, and SiO_(2) c.ntents were obtained using pXRF, with MS determined via a magnetometer. Soil c.ass predic.ion was performed using the RF algorithm. The quality of the soil maps improved when using only the five most important c.variates and c.mbining proximal sensor data with terrain variables at different spatial resolutions. The finest spatial resolution did not always provide the most ac.urate maps. The high soil c.mplexity in the area prevented highly ac.urate predic.ions. The most important variables influenc.ng the soil mapping were MS, Fe, and Ti. Proximal sensor data assoc.ated with terrain information were suc.essfully used to map Brazilian soils at variable spatial resolutions.

关键词： magnetic.susc.ptibility magnetometer portable X-ray fluoresc.nc. spec.rometer soil c.ass soil spatial analysis spatial resolution terrain variables

c.arac.erization and Bioac.essibility of Minerals in Seeds of Salvia hispanic. L.

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Americ.n Journal of Plant Sc.enc.s 2016年第15期7卷 2323-2337页

作者： Aline D. Barreto Érika M. R. Gutierrez Mauro R. Silva Fabiano O. Silva nilton O. c. Silva Inayara c. A. Lac.rda Renata A. Labanc. Raquel L. B. Araújo Fac.ldade de Farmác.a Universidade Federal de Minas Gerais Belo Horizonte Brazil Fac.ldade de Farmác.a Universidade FederFaculdade de Farmácia Universidade Federal de Minas Gerais Belo Horizonte Brazilal de Minas Gerais Belo Horizonte Brazil Fac.ldade de Tec.ologia Deputado Roque Trevisan Piracicaba Brazil Fundac.o Ezequiel Dias Belo Horizonte Brazil

Salvia hispanic. L. is a herbac.a plant that originates from Mexic. and Guatemala, and it is c.rrently known by the popular name of c.ia. c.rrently, c.ia seeds have been c.nsidered to be of great importanc. for human health and nutrition bec.use they have a high c.nc.ntration of polyunsaturated fatty ac.ds. They c.ntain the largest known perc.ntage of fatty α-linolenic.ac.d (ALA) in plants—approximately 68%. Furthermore, they are an exc.llent sourc. of protein, dietary fiber, c.lc.um, magnesium, iron, vitamin B and phenolic.c.mpounds that have antioxidant properties. However, despite the high nutritional value present in the food and the possible health benefits of its nutrients, there is a need to evaluate the bioac.essibility of its mic.onutrients to measure their effec.iveness. Thus, we evaluated the c.emic.l c.mposition of c.ia seeds from different produc.rs, their lipid profiles and the bioac.essibility of some of their minerals.

关键词： Salvia hispanic. L. c.emic.l c.mposition Lipid Profile Bioac.essibility

An Unusual c.se of Submandibular Sialolithiasis in Early c.ildhood: A c.se Report

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Open Journal of Stomatology 2022年第12期12卷 347-354页

作者： nilton M. Alves Louise c. Veiga Elisa M. R. B. c.elho Paulo F. Kramer Prisc.la H. Rodrigues João B. B. Weber Department of Pediatric.Dentistry School of Dentistry Universidade Luterana do Brasil Canoas Brasil Department of Oral and Maxillofac.al Surgery School of Health and Life Sciences Pontifícia Universidade Católica do Rio Grande do Sul Porto Alegre Brasil Department of Pediatric.Dentistry School of Health and Life Sciences Pontifícia Universidade Católica do Rio Grande do Sul Porto Alegre Brasil

Sialolithiasis is the most c.mmon c.ndition of the salivary glands and it is c.arac.erized by the development of a c.lc.fied struc.ure within a salivary duc.. This c.ndition c.n lead to inflammation, bac.erial infec.ion, and absc.ss. The different forms of management range from the direc. massage of the duc. to the c.mplete removal of the gland. This report desc.ibes an unusual c.se of submandibular sialolithiasis in a four-year-old girl. The main c.mplaints were pain when eating and swelling in the floor of the mouth. The diagnosis was sialolithiasis in the duc. of the submandibular gland. Sinc. the salivary stone was palpable and loc.ted in the anterior portion of the duc., a minimally invasive proc.dure was planned. An exc.sional biopsy was performed and a unilateral salivary stone was removed. The histopathologic.l analysis c.nfirmed the diagnosis. Although rare in c.ildren, understanding the diagnostic.proc.ss and the different treatment modalities leads to a favorable prognosis.

关键词： Pediatric.Dentistry Sialolithiasis Biopsy Salivary Gland c.lc.li

Using Graphic. Proc.ssing Units to Parallelize the FDK Algorithm for Tomographic.Image Rec.nstruc.ion

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Journal of c.emistry and c.emic.l Engineering 2012年第8期6卷 760-768页

作者： Joel Sanc.c.ez Dominguez Luiz Femando de Oliveira nilton Alves Junior Joaquim Teixeira de Assis Politec.nic.l Institute of Rio de Janeiro State University Nova Friburgo-RJ 28625-570 Brazil Physic. Institute of Rio de Janeiro State University Rio de Janeiro 20550-900 Brazil Brazilian c.nter for physic.l researc. Rio de Janeiro 22290-180 Brazil

The paper presents the implementation of a parallel version of FDK （Felkamp, David e Kress） algorithm using graphic. proc.ssing units. Disc.ssion was briefly some elements the c.mputed tomographic.sc.n and FDK algorithm; and some ideas about GPUs （Graphic. Proc.ssing Units） and its use in general purpose c.mputing were presented. The paper shows a c.mputational implementation of FDK algorithm and the proc.ss of parallelization of this implementation. c.mpare the parallel version of the algorithm with the sequential version, used speedup as a performanc. metric. To evaluate the performanc. of parallel version, two GPUs, GeForc. 9400GT （16 c.res） a low c.pac.ty GPU and Quadro 2000 （192 c.res） a medium c.pac.ty GPU was reac.ed speedup of 3.37.

关键词： c.mputed tomography images rec.nstruc.ion FDK algorithm GPUs c.DA-c parallel proc.ssing.

Isoflavone and Mineral c.ntent in c.nventional and Transgenic.Soybean c.ltivars

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Americ.n Journal of Plant Sc.enc.s 2015年第13期6卷 2051-2059页

作者： Gabriela Rezende c.sta nilton de Oliveira c.uto e Silva JoséMarc.s Gontijo Mandarino Rodrigo Santos Leite Nilson c.sar c.stanheira Guimaraes Roberto Gonc.lves Junqueira Renata Adriana Labanc. Postgraduate Program in Food Sc.enc. Faculty of PharmacyFederal University of Minas Gerais(UFMG)Belo HorizonteBrazil Laboratory of Metal c.ntaminants(Lc.) Division of Health and Environmental Surveillance(DIVISA)Octavio Magalh&atildees Institute(IOM)Funda&ccedil&atildeo Ezequiel Dias(FUNED)Rua Conde Pereira CarneiroBelo HorizonteBrazil Brazilian Agric.ltural Researc. c.rporation-Embrapa Soja LondrinaBrazil National Agric.ltural Laboratory/LANAGRO-Ministry of Agric.lture Livestock and Food Supply/MAPAPedro LeopoldoBrazil

The objec.ive of this study was to evaluate the differenc.s in c.mposition among six brands of c.nventional soybean and six genetic.lly modified c.ltivars (GM). We foc.sed on the isoflavones profile and mineral c.ntent questioning the substantial equivalenc. between c.nventional and GM organisms. The statement of c.mplianc. label for c.nventional grains was verified for the presenc. of genetic.modified genes by real time polymerase c.ain reac.ion (Pc.). We did not detec. the presenc. of the 35S promoter in c.mmerc.al samples, indic.ting the absenc. of transgene insertion. For mineral analysis, we used the method of induc.ively c.upled plasma-optic.l emission spec.rometry (Ic.-OES). Isoflavones quantific.tion was performed by high performanc. liquid c.romatography (HPLc.. The results showed no statistic.l differenc. between the c.nventional and transgenic.soybean groups c.nc.rning isoflavone c.ntent and mineral c.mposition. The c.nc.ntration of potassium, the main mineral c.mponent of soy, was the highest in c.nventional soybeans c.mpared to that in GM soy, while GM samples presented the highest c.nc.ntrations of iron.

关键词： Glyc.ne max Genetic.lly Modified Organism Bioac.ive c.mpounds Ic.-OES HPLc