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Voltammetric sensor based on cobalt-poly(methionine)-modified glassy carbon electrode for determination of estriol hormone in pharmaceuticals and urine

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Journal of Pharmaceutical Analysis 2019年第5期9卷 347-357页

作者： Eliziana S. Gomes Fernando R.F. Leite Bruno R.L. Ferraz Henrique A.J.L. Mourao Andrea R. Malagutti Department of Pharmacy Faculty of Biological and Health Sciences Federal University of Jequitinhonha and Mucuri Valleys MGT 367 Highway e Km 583 CEP 39100-000 Diamantina MG Brazil Department of Biology Federal University of Espírito Santo CEP 29500-000 Alegre ES Brazil Institute of Science and Technology Federal University of Jequitinhonha and Mucuri Valleys MGT 367 Highway e Km 583 CEP 39100-000 Diamantina MG Brazil

A voltammetric sensor based on the electropolymerization of cobalt-poly(methionine)(Co-poly(Met)) on a glassy carbon electrode (GCE) was developed and applied for the determination of estriol by differential pulse voltammetry (DPV) for the first time. The electrochemical properties of the Co-poly(Met)/GCE were analysed by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were used to characterize the polymers on the GCE surface. The deposition of the Co-poly(Met) film on the GCE surface enhanced the sensor electronic transfer. CV studies revealed that estriol exhibits an irreversible oxidation peak at t0.58 V for the Co-poly(Met)/GCE (vs. Ag/AgCl reference electrode) in 0.10 mol/L Britton-Robinson buffer solution (pH=7.0). Different voltammetric scan rates (10-200 mV/s) suggested that the estriol oxidation on the Co-poly(Met)/GCE surface is controlled by adsorption and diffusion processes. Based on the optimized DPV conditions, the linear responses for estriol quantification were from 0.596 μmol/L to 4.76 μmol/L (R2 =0.996) and from 5.66 μmol/L to 9.90 μmol/L (R2 =0.994) with a limit of detection (LOD) of 0.0340 μmol/L and a limit of quantification (LOQ) of 0.113 μmol/L. The DPV-Co-poly(Met)/GCE method provided good intra-day and inter-day repeatability with RSD values lower than 5%. Also, no interference of real sample matrices was observed on the estriol voltammetric response, making the DPV-Copoly( Met)/GCE highly selective for estriol. The accuracy test showed that the estriol recovery was in the ranges 96.7%-103% and 98.7%-102% for pharmaceutical tablets and human urine, respectively. The estriol quantification in pharmaceutical tablets performed by the Co-poly(Met)/GCE-assisted DPV method was comparable to the official analytical protocols.

关键词： Estriol Electroanalysis Differential pulse voltammetry Cobalt-poly(methionine) film-modified glassy carbon electrode

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Energy transfer in double plate system dynamics

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Acta Mechanica Sinica 2008年第3期24卷 331-344页

作者： Katica (Stevanovi) Hedrih Faculty of Mechanical Engineering Mathematical Institute SANUUniversity of Niul.Vojvode Tankosia 3/2218 000 NiSerbia

The study of energy transfer between coupled subsystems in a hybrid system is very important for applications. This paper presents an analytical analysis of energy transfer between plates of a visco-elastically connected double-plate system in free transversal vibrations. The analytical analysis shows that the visco-elastic connection between plates is responsible for the appearance of two-frequency regime in the time function, which corresponds to one eigen amplitude function of one mode, and also that time functions of different vibration modes are uncoupled, but energy transfer between plates in one eigen mode appears. It was shown for each shape of vibrations. Series of the two Lyapunov exponents corresponding to the one eigen amplitude mode are expressed by using the energy of the corresponding eigen amplitude time component.

关键词： Energy transfer between subsystems Doubleplate system Multifrequency transversal vibrations Analytical solution Rayleigh function of dissipation

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Silymarin Attenuates Hepatic and Pancreatic Redox Imbalance Independent of Glycemic Regulation in the Alloxan-induced Diabetic Rat Model

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Biomedical and Environmental Sciences 2020年第9期33卷 690-700页

作者： Miranda Laise Mara Oliveira Agostini Livia da Cunha Lima Wanderson Geraldo de Camini Fernanda Caetano Costa Daniela Caldeira Programa de Pos-graduagao em Saude e Nutricao Escola de NutricaoUniversidade Federal de Ouro PretoOuro PretoMinas Gerais 35400-000Brazil Escola de Farmacia Universidade Federal de Ouro Preto.Ouro PretoMinas Gerais 35400-000Brazil Laboratorio de Morfopatologia Departamento de Ciencias BioldgicasUniversidade Federal de Ouro PretoOuro Preto 35400-000Brazil Programa de Pos-graduaqao em Ciencias Bioldgicas Nucleo de Pesquisas em Ciencias BiologicasUniversidade Federal de Ouro Preto.Ouro Preto 35400-000Brazil Laboratorio de Bioquimica Metabolica Departamento de Ciencias BiologicasUniversidade Federal de Ouro PretoOuro Preto 35400-000Brazil

Objective To evaluate the efficiency of silymarin(SMN) in modulating metabolic parameters and redox status in rats with type 1 diabetes mellitus(T1 DM).Methods Diabetes was induced by intraperitoneal injection of alloxan. The diabetic rats were administered with SMN at doses of 50 and 100 mg/kg body weight/d for 30 consecutive days. The rats were divided into the following four groups: vehicle control, diabetic(alloxan-treated), DS50(alloxan +50 mg/kg body weight/d of SMN), and DS100(alloxan + 100 mg/kg body weight/d of SMN) groups. The bodyweight and food and water intake were evaluated. After 30 d, the animals were euthanized and the blood was collected for measuring the serum levels of glucose, triacylglycerol(TAG), urea, and creatinine. The liver and pancreas were collected for measuring the activities of superoxide dismutase(SOD) and catalase(CAT), and the levels of carbonylated protein(PC). The pancreas sample was also used for histological *** SMN reduced hepatic(P < 0.001) and pancreatic(P < 0.001) protein damage and creatinine levels(P = 0.0141) in addition to decreasing food(P < 0.001) and water intake(P < 0.001). However,treatment with SMN did not improve beta-cell function or decrease blood glucose levels in diabetic *** SMN improved polyphagia and polydipsia, renal function, and protected the liver and pancreas against protein damage without affecting hyperglycemia in diabetic animals.

关键词： Silymarin Silybum marianum Type 1 diabetes Oxidative stress

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Understanding bark thickness variations for Araucaria angustifolia in southern Brazil

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Journal of Forestry Research 2021年第3期32卷 1077-1087页

作者： Emanuel Arnoni Costa Veraldo Liesenberg César Augusto Guimaraes Finger AndréFelipe Hess Cristine Tagliapietra Schons Graduate Program in Forest Engineering Santa Catarina State University(UDESC)LagesSC 88520-000Brazil Department of Forest Engineering Federal University of Uberlandia(UFU)Monte CarmeloMG 38500-000Brazil Graduate Program in Forest Engineering Federal University of Santa Maria(UFSM)Santa MariaRS 97105-900Brazil Graduate Program in Agroecosystems Federal Technological University of Parana(UFTPR)Dois VizinhosPR 85660-000Brazil

This study aimed to understand bark thickness variations of Araucaria angustifolia(Bertol.)Kuntze trees growing in natural forest remnants in southern Brazil,and their relationship with quantitative and qualitative *** thickness must be accurately estimated in order to determine timber volume *** is an important variable for the sustainable management and conservation of araucaria *** spite of its importance and visibility,bark thickness variations have not been evaluated for this key species in southern Brazil.A total of 104 trees were selected,and their qualitative and quantitative attributes such as diameter at breast height(D_(BH)),height(H),crown base height(C_(BH)),crown length(C_(L)),social position(S_(P)),stoniness(S_(T)),position on the relief(P_(R)),vitality(V_T)and branch arrangement(B_(A))were *** trees were categorized into two groups:red bark or gray *** analysis and artificial neural networks(ANN)were used for modelling bark *** results indicate that:(1)bark thickness showed good correlation to D_(BH),with 0.76 as coefficient of determination(RS_P),0.540 as Mean Absolute Error(M_(AE))and 22.4 root-meansquare error in percentage(R_(MSE%));(2)the trend changed according to bark colour,with significant differences for the intersection(_0–Pr>F:p=0.0124)and slope(β_(1)–Pr>F:p=0.0126)of bark thickness curves between groups;(3)the highest correlation of bark thickness was found with:D_(BH)(ρ=0.88),H(ρ=0.58),C_(BH)(ρ=0.46),S_(P)(ρ=-0.52),and B_(A)(ρ=-0.32);(4)modelling with ANN confirmed high adjustment(R^(2)=0.99)and accuracy(R_(MSE%)=3.0)of the *** is an efficient and robust technique for the modelling of various qualitative and quantitative attributes commonly used in forest *** effective use of ANN to estimate araucaria bark in natural forests reinforces its potential,besides the possibility of application for other forest species.

关键词： Dendrometry attributes Crown characteristics Prediction models Bark factor Parana-pine

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Characterization of atmospheric aerosol (PM10 and PM2.5) from a medium sized city in S?o Paulo state,Brazil

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Journal of Environmental Sciences 2020年第3期32卷 238-251页

作者： Bruno T.Franzin Filipe C.Guizellini Diego V.de Babos Ossamu Hojo Ieda Ap.Pastre Mary R.R.Marchi Fernando L.Fertonani Cristina M.R.R.Oliveira Sao Paulo State University(Unesp) Chemistry InstituteAnalytical Chemistry DepartmentAraraquaraSP14800-060Brazil Federal University of Sao Carlos-UFSCAr Chemistry DepartmentSao CarlosSP13565-905Brazil Chemistry and Environmental Sciences Department BiosciencesLanguages and Exact Sciences InstituteIbilceSaoPaulo State University(Unesp)Sao Jose do Rio PretoSP15054-000Brazil Centro de Quimica Estrutural-Faculdade de Ciencias da Universidade de Lisboa Edif.C8Campo Grande1749-016 LisboaPortugal

Air pollution causes deleterious effects on human health with aerosols being among the most polluting *** objective of this work is the characterization of the PM2.5 and PM10 aerosol mass in the *** methods of analysis include WD-XRF and *** were correlated with meteorological information and air mass trajectories(model HYSPLIT)by multivariate analysis.A morphological structural analysis was also carried out to identify the probable sources of atmospheric aerosols in the city of Sao Jose do Rio Preto,*** mean mass concentration values obtained were 24.54 μg/m^3 for PM10,above the WHO annual standard value of 20 μg/m^3 and 10.88 μg/m^3 for PM2.5 whose WHO recommended limit is10 μg/m^***-XRF analysis of the samples revealed Si and Al as major components of the coarse *** the fine fraction,the major elements were Al and *** SEM-FEG characterization allowed identifying the morphology of the particles in agglomerates,ellipsoids and filaments in the PM10,besides spherical in the *** analysis by EDS corroborated WD-XRF results,identifying the crustal elements,aluminosilicates and elements of anthropogenic origin in the coarse *** the fine fraction crustal elements were also identified;aluminosilicates,black carbon and spherical particles(C and O) originating from combustion processes were *** use of multivariate analysis to correlate air mass trajectories with the results of the morpho-structural characterization of the particulate matter allowed confirmation of the complex composition of the particles resulting from the combination of both local and long-distance sources.

关键词： Urban aerosol PM10 PM2.5 WD-XRF SEM-EDS

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Enteric nervous system and inflammatory bowel diseases:Correlated impacts and therapeutic approaches through the P2X7 receptor

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World Journal of Gastroenterology 2021年第46期27卷 7909-7924页

作者： Henrique Inhauser Riceti Magalhães Patricia Castelucci Department of Surgery School of Veterinary Medicine and Animal SciencesUniversity of São PauloSão Paulo 08000-000Brazil Department of Anatomy Institute of Biomedical SciencesUniversity of São PauloSão Paulo 08000-000Brazil

The enteric nervous system(ENS)consists of thousands of small ganglia arranged in the submucosal and myenteric plexuses,which can be negatively affected by Crohn’s disease and ulcerative colitis-inflammatory bowel diseases(IBDs).IBDs are complex and multifactorial disorders characterized by chronic and recurrent inflammation of the intestine,and the symptoms of IBDs may include abdominal pain,diarrhea,rectal bleeding,and weight *** P2X7 receptor has become a promising therapeutic target for IBDs,especially owing to its wide expression and,in the case of other purinergic receptors,in both human and model animal enteric ***,little is known about the actual involvement between the activation of the P2X7 receptor and the cascade of subsequent events and how all these activities associated with chemical signals interfere with the functionality of the affected or treated *** this review,an integrated view is provided,correlating the structural organization of the ENS and the effects of IBDs,focusing on cellular constituents and how therapeutic approaches through the P2X7 receptor can assist in both protection from damage and tissue preservation.

关键词： Chemical coding Enteric nervous system Gastroenterology Inflammatory bowel diseases P2X7 receptor Purinergic signaling

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A comprehensive study on the processing of Co:ZnO nanostructured ceramics:Defect chemistry engineering and grain growth kinetics

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Journal of Materials Science & Technology 2023年第7期138卷 221-232页

作者： R.T.da Silva J.M.Morbec G.Rahman H.B.de Carvalho Universidade Federal de Ouro Preto-UFOP Ouro PretoMG 35400-000Brazil School of Chemical and Physical Sciences Keele UniversityKeele ST55BGUnited Kingdom Department of Physics Quaid-i-Azam UniversityIslamabad 45320Pakistan Universidade Federal de Alfenas-UNIFAL Alfenas 37130-000Brazi

In this report,we present a systematic study on the preparation of Co:ZnO ceramics via a standard solid-state route from different Co precursors(Co_(3)O_(4),CoO,and metallic Co)and atmospheres(O_(2)and Ar).Particular emphasis is given to defect chemistry engineering and the sintering growth ***-principles calculations based on density functional theory are employed to determine the formation en-ergy of the main point defects in ZnO and Co:ZnO *** on the theoretical results,a set of chemical reactions is *** microstructural characterization is also performed to determine the degree of Co incorporation into the ZnO *** samples prepared in Ar atmosphere and metal-lic Co present the highest Co solubility limit(lower apparent Co incorporation activation energy)due to the incongruent ZnO *** of the parameters of the sintering growth kinetics reveals that Co_(3)O_(4)is the best sintering additive to achieve larger grain sizes,and possible higher densi-ties,in both sintering atmospheres,while metallic Co is the best to achieve the smallest grain size with higher Co concentration and homogeneous spatial distribution for a subsequent reduction of *** results show that the sintering in O_(2)effectively promotes zinc vacancies in the ZnO structure,while the sintering in Ar promotes zinc interstitial *** findings contribute to understanding the preparation of Co-doped ZnO ceramics and the sintering growth kinetics,which may improve the state of the art in processing the material at both bulk and nanometric scales.

关键词： Multifunctionality Zinc oxide Defect engineering Growth kinetics

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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 CURI Departamento de Ciéncia do Solo Universidade Federal de LavrasCampusLavras MG 37200-000Brazil

Soils result from the interaction of five independent formation *** one factor varies,while the others remain constant,different soils can be ***,we demonstrated an opposing trend,wherein two soils were similar,despite considerable differences in all factors of soil *** sampled two Inceptisols(Oxic Dystrudepts) formed on different parent materials(gneiss *** schist),climate(tropical altimontane ***,drier plateau),topography(1 650 m,45% slope vs.1 000 m,8% slope),time(rejuvenated ***,stable surface),and vegetation(rainforest *** savanna).The two soils had similar chemical properties,whereas the soil on mica schist had finer particle size distribution,lower porosity,and lower saturated hydraulic *** properties were related to a coarser blocky microstructure compared to the soil on *** soils presented active mineral weathering and pronounced pedoplasmation,demonstrated by clay contents>300 g kg^(-1),although only the Dystrudept on gneiss possessed coarse rock *** C horizons of both soils presented fragmented clay coatings suggestive of argilluviation,likely relict,because they were not observed in the B *** similarities in many properties of the two Dystrudepts,despite contrasting factors of soil formation,suggest converging evolution and that soil classification at the subgroup level was efficient in grouping similar formative processes in tropical ***,this work revealed that similar pedogenic processes acting on different factors of soil formation can result in similar soil properties,at least for Inceptisols where further soil development is hindered by topographic limitations.

关键词： mineral weathering, Oxic Dystrudept, pedogenic process, soil genesis, soil micromorphology, soil property, soil taxonomy

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Height-to-diameter ratios with temporal and dendro/morphometric variables for Brazilian pine in south Brazil

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Journal of Forestry Research 2021年第1期32卷 191-202页

作者： Andre Felipe Hess Myrcia Minatti Emanuel Arnoni Costa Luis Paulo Baldissera Schorr Gabriel Teixeira da Rosa Isadora de Arruda Souza Geedre Adriano Borsoi Veraldo Liesenberg Thiago Floriani Stepka Roberta Abatti Department of Forest Engineering Santa Catarina State University2090 Luiz de Camoes AvenueLagesSanta Catarina State 88520-000Brazil Department of Forest Engineering Federal University of Parana(UFPR)Pref.Lothario Meissner Ave.900CuritibaParana 80060-000Brazil

Height-to-diameter ratios(HD)are an important measure of the stability,density and competition of forest *** refl ects the vertical growth of the trees,the vulnerability of the forest canopy structure and infl uences volumetric *** ratios vary according to tree size,availability of resources for growth,stand density and species *** were taken from 210 trees and a regression technique of generalized linear models for the HD ratio applicable for forest structure conservation was *** objective of this study was to model the HD ratios of dominant and co-dominant trees of Araucaria angustifolia according to morphometric,dendrometric,annual diameter increment,stand density,and age variables in three sites in southern *** results show that the HD ratio decreases with increasing age,crown area and basal area,and increases with stand density and annual diameter *** of the developed equations was demonstrated by the values of deviation,Bayesian and Akaike *** results are of interest to forest managers since they make decisions about silvicultural *** continuity and forest production indicate that any intervention should be directed at younger trees of smaller sizes,and that one of the main management factors for stand stability and growth is the formation of the stand and its capture of light.

关键词： Forest management Mixed forests Conservation Araucaria angustifolia

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Beverage composed of fruits and soy:Microbiology,colorimetry and effects of refrigerated storage on physical-chemical parameters

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Food Bioscience 2022年第5期49卷 1084-1089页

作者： Bruno Fonsˆeca Feitosa Emanuel Neto Alves de Oliveira Francisco Bruno Ferreira de Freitas Juvˆencio Oleg´ario de Oliveira Neto Regilane Marques Feitosa Thamirys Lorranne Santos Lima Maria Lucimar da Silva Medeiros Jo˜ao Vitor Fonseca Feitoza Henrique D.M.Coutinho State University of Campinas Faculty of Food EngineeringCampinasSP13083-970Brazil Federal Institute of Education Science and Technology of Rio Grande do Norte(IFRN)Pau dos Ferros Campus Pau dos FerrosRio Grande do Norte59900-000Brazil Federal University of Campina Grande Campus Pombal-PB58840-000Brazil Federal Institute of Education Science and Technology of Alagoas57625-000Brazil Federal Institute of Education Science and Technology of Rio Grande do Norte(IFRN)Campus Pau dos FerrosRio Grande do Norte59900-000Brazil Federal Institute of Education Science and Technology of Rio Grande do Norte(IFRN)Campus Currais NovosRio Grande do Norte59380-000Brazil Federal University of Cear´a Center for Agrarian SciencesFortalezaCE59700000Brazil Department of Biological Chemistry Regional University of Cariri-URCA63105-000CratoCEBrazil

The study aimed to develop beverages composed of fruits and soy extract,to evaluate the microbiology,colorimetry and the effects of refrigerated storage(4±2℃)on the physicochemical *** concentrate(50,55,60,65,70,75 and 80%)and myrtle pulp(30,25,20,15,10,5 and 0%)were used for the preparation of seven beverage formulations composed in different proportions,added with inulin and sweetened with honey *** analyzes were performed after processing and physicochemical stability was determined every 4 days for 8 *** beverages composed showed adequate microbiological quality after *** partial replacement of myrtle pulp by mango concentrate influenced mainly the colorimetric parameters,as well as pH,total acidity,total soluble solids and TSS/TTA *** beverages with greater stability were those made with 50 and 55%mango and 30 and 25%myrtle,respectively,both with 13%soy *** is inferred that the development of beverage composed of fruits and soy for specific emerging audiences may be viable,and complementary analyzes and a longer storage period are recommended for more stable beverages.

关键词： Eugenia gracillima Kiaersk Glycine max Mangifera indica L Mixed juice Stability study

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