cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.7046132
title: Effect of brushing and beverages on surface roughness of ceramic brackets

description: Abstract Introduction When introduced into the oral environment, the ceramic brackets may undergo change their structure caused by the process of chemical and mechanical degradation of the material. Objective This study evaluated the surface roughness of ceramic brackets and whether it is altered by toothbrushing process and diet solutions. Material and method Seven ceramic brackets of four commercial brands were tested: two monocrystalline and two polycrystalline. The brackets were immersed in solutions of coffee, red wine, Coke, black tea and artificial saliva for 21 days. Another group of brackets of each brand were also immersed in the same solutions and for an equal time, but with daily brushing performed by a toothbrushing machine. The surface roughness (Ra) was analyzed by a Roughness Tester (Surftest SJ–400,Mitutoyo®) before and after 24 hours, 7, 14 and 21 days. The data were evaluated by the Analysis of Multivariate Profiles, Analysis of Variance (ANOVA), multiple comparison test of means. Result The results of Ra and its change after 21 days were: Ra mean of Allure = 0.277μm (change = 0.002μm), Inspire Ice = 0.262μm (change = 0.013μm), Radiance = 0.177μm change = 0.009μm), Transcend = 0.367μm (change = 0.019μm). Conclusion the surface roughness of the ceramic brackets increased after 21 days of immersion in the solutions, and the immersion time was a significant factor. However, this change in the surface roughness was similar for the monocrystalline and polycrystalline brackets, as well as for the different solutions. Brushing did not change the surface roughness of ceramic brackets.
DOI: 10.6084/m9.figshare.7046135.v1
title: Electronic government services in Brazil: an analysis based on measures of access and users’ internet skills

description: Abstract This article aims to analyze how measures to promote Internet access, and users’ competencies influence the use of electronic government services in Brazil. We adopted Sen’s Capability Approach as theoretical framework in order to analyze the microdata from the ICT Households 2013, a national-wide survey coordinated by the Regional Center for Studies on Development of the Information Society (Cetic.br). The results indicate that for social classes C (middle class), D and E (lower class) the increase in the odds ratio of the use of e-gov services is strongly influenced by both internet access preferably at home or work (individual access) as well as the users’ internet skills.
DOI: 10.6084/m9.figshare.7046132.v1
title: Effect of brushing and beverages on surface roughness of ceramic brackets

description: Abstract Introduction When introduced into the oral environment, the ceramic brackets may undergo change their structure caused by the process of chemical and mechanical degradation of the material. Objective This study evaluated the surface roughness of ceramic brackets and whether it is altered by toothbrushing process and diet solutions. Material and method Seven ceramic brackets of four commercial brands were tested: two monocrystalline and two polycrystalline. The brackets were immersed in solutions of coffee, red wine, Coke, black tea and artificial saliva for 21 days. Another group of brackets of each brand were also immersed in the same solutions and for an equal time, but with daily brushing performed by a toothbrushing machine. The surface roughness (Ra) was analyzed by a Roughness Tester (Surftest SJ–400,Mitutoyo®) before and after 24 hours, 7, 14 and 21 days. The data were evaluated by the Analysis of Multivariate Profiles, Analysis of Variance (ANOVA), multiple comparison test of means. Result The results of Ra and its change after 21 days were: Ra mean of Allure = 0.277μm (change = 0.002μm), Inspire Ice = 0.262μm (change = 0.013μm), Radiance = 0.177μm change = 0.009μm), Transcend = 0.367μm (change = 0.019μm). Conclusion the surface roughness of the ceramic brackets increased after 21 days of immersion in the solutions, and the immersion time was a significant factor. However, this change in the surface roughness was similar for the monocrystalline and polycrystalline brackets, as well as for the different solutions. Brushing did not change the surface roughness of ceramic brackets.
DOI: 10.6084/m9.figshare.7046126
title: Ga Dopant Induced Band Gap Broadening and Conductivity Enhancement in Spray Pyrolysed Zn0.85Ca0.15O thin Films

description: Ga doped Zn0.85Ca0.15O thin films were prepared by spray pyrolysis method and studied the impact of Ga doping concentration on the physical properties of these films. XRD analysis confirmed the structural purity and polycrystalline nature of the films and composition analysis verified the incorporation of dopants in the structures. Optical transmission in the visible range initially increased and at higher Ga concentration decreased in accordance with the crystalline quality. Energy gap increased with doping percentage due to Burstein-Moss effect arising from the increase in carrier concentration. Ga doping resulted in enhanced electron concentration and consequently obtained lower resistive n type thin films. At higher doping level, electron density decreased due to the limit of solid solubility and hence conductivity slightly decreased but energy gap increased due to the extended localization arising from the poor crystallinity. Mobility decreased with doping due to the increased ionized impurity scattering at lower dopant concentration and due to intra-grain cluster scattering at heavy doping.
DOI: 10.6084/m9.figshare.7046123
title: Production of Pure Granules Of Sba-15 Mesoporous Silica

description: Mesoporous silica materials have been widely investigated for their great potential as competitive adsorbents and catalysts in different areas, due to their ordered and uniform porous structures and high surface area. In order to increase the availability of these materials, the need to granulate them becomes vital for an efficient performance in industrial units. This study reports the production and characterization of clay-free granules of SBA-15 mesoporous silica, by applying the extrusion technique. The suggested methodology uses only methocel as the organic binder, which is removed after calcination. The granulation process was successfully achieved, producing pure granules of SBA-15 mesoporous silica, in size of millimeters, with 8.3 MPa of compacting pressure (by axial crushing test). The surface area and pore volume of SBA-15 mesoporous silica granules (calcined at 800 ºC) were around 392 m2/g and 0.53 cm3/g, respectively.
DOI: 10.6084/m9.figshare.7046123.v1
title: Production of Pure Granules Of Sba-15 Mesoporous Silica

description: Mesoporous silica materials have been widely investigated for their great potential as competitive adsorbents and catalysts in different areas, due to their ordered and uniform porous structures and high surface area. In order to increase the availability of these materials, the need to granulate them becomes vital for an efficient performance in industrial units. This study reports the production and characterization of clay-free granules of SBA-15 mesoporous silica, by applying the extrusion technique. The suggested methodology uses only methocel as the organic binder, which is removed after calcination. The granulation process was successfully achieved, producing pure granules of SBA-15 mesoporous silica, in size of millimeters, with 8.3 MPa of compacting pressure (by axial crushing test). The surface area and pore volume of SBA-15 mesoporous silica granules (calcined at 800 ºC) were around 392 m2/g and 0.53 cm3/g, respectively.
DOI: 10.6084/m9.figshare.7046126.v1
title: Ga Dopant Induced Band Gap Broadening and Conductivity Enhancement in Spray Pyrolysed Zn0.85Ca0.15O thin Films

description: Ga doped Zn0.85Ca0.15O thin films were prepared by spray pyrolysis method and studied the impact of Ga doping concentration on the physical properties of these films. XRD analysis confirmed the structural purity and polycrystalline nature of the films and composition analysis verified the incorporation of dopants in the structures. Optical transmission in the visible range initially increased and at higher Ga concentration decreased in accordance with the crystalline quality. Energy gap increased with doping percentage due to Burstein-Moss effect arising from the increase in carrier concentration. Ga doping resulted in enhanced electron concentration and consequently obtained lower resistive n type thin films. At higher doping level, electron density decreased due to the limit of solid solubility and hence conductivity slightly decreased but energy gap increased due to the extended localization arising from the poor crystallinity. Mobility decreased with doping due to the increased ionized impurity scattering at lower dopant concentration and due to intra-grain cluster scattering at heavy doping.
DOI: 10.6084/m9.figshare.7046114
title: Poly (Methyl Methacrylate)-SiC Nanocomposites Prepared Through in Situ Polymerization

description: In this study, polymeric nanocomposites based on poly(methyl methacrylate) (PMMA) and silicon carbide (SiC) nanoparticles were prepared by radical mass polymerization in the presence of filler. Nanoparticles of SiC with and without surface treatment with organosilane were obtained .The nanocomposites were characterized by X-ray fluorescence (XRF), infrared spectroscopy (FTIR), thermogravimetry (TGA) and Field Emission Gun Scanning Electron Microscopy (FEG SEM) with an energy dispersive x-ray spectroscopy (EDS) detector. The produced nanocomposites showed well-dispersed SiC incorporation in the PMMA matrix. The results pointed that the surface treatment on SiC fillers was successful on enhancing the interaction between the organic matrix and the inorganic filler.
DOI: 10.6084/m9.figshare.7046114.v1
title: Poly (Methyl Methacrylate)-SiC Nanocomposites Prepared Through in Situ Polymerization

description: In this study, polymeric nanocomposites based on poly(methyl methacrylate) (PMMA) and silicon carbide (SiC) nanoparticles were prepared by radical mass polymerization in the presence of filler. Nanoparticles of SiC with and without surface treatment with organosilane were obtained .The nanocomposites were characterized by X-ray fluorescence (XRF), infrared spectroscopy (FTIR), thermogravimetry (TGA) and Field Emission Gun Scanning Electron Microscopy (FEG SEM) with an energy dispersive x-ray spectroscopy (EDS) detector. The produced nanocomposites showed well-dispersed SiC incorporation in the PMMA matrix. The results pointed that the surface treatment on SiC fillers was successful on enhancing the interaction between the organic matrix and the inorganic filler.
DOI: 10.6084/m9.figshare.7046105
title: Morpho-physiological characteristics by sweet potato cultivars as function of irrigation depth

description: Abstract The sweet potato is an alternative energy source, but its sustainability depends on efficient water use. The objective of this study was to evaluate sweet potato morpho-physiological characteristics, and water use efficiency (WUE). Irrigation depths of 50, 75, 100, and 125% of crop evapotranspiration (ETc) were applied. The morpho-physiological indicators, WUE, leaf area index (LAI), leaf water potential, leaf temperature, and leaf chlorophyll index (ICF), were evaluated. The WUE of the sweet potato cultivars increased until the 75% water depth of the ETc. The LAI of these cultivars increased with irrigation depth, with higher values at 100% of the ETc. The leaf water potential of the two sweet potato cultivars was lowest with the lower irrigation depth. Leaf temperature was closer to that of ambient temperatures in treatments with greater irrigation depth. The increase of the WUE with the greater accumulation of dry biomass is due to greater CO2 diffusion by stomata. The reduction in the growth of these plants is due to water stress limiting stomatal conductance, transpiration, leaf growth (LAI) and chlorophyll concentration, proportional to soil moisture conditions. The functional relationship between soil moisture and growth is essential to optimize irrigation management at different growth stages.
DOI: 10.6084/m9.figshare.7046108
title: BOARD OF DIRECTORS: THE PERSPECTIVE OF INDEPENDENTS IN THE PERFORMANCE OF PRIVATE ORGANIZATIONS? EVIDENCES IN BRAZIL

description: ABSTRACT Purpose: The study seeks to verify the influence of the board of directors’ independence on the performance of BM&FBOVESPA listed companies and to analyse which agency conflicts influence the performance of the board of directors. Originality/value: The factor of Brazil being an emerging country which lacks a strict legal system and control factors against corruption in these environments and the public sectors emphasizes the importance of applying the best corporate governance practice code in the main developed countries, reflecting the need for effective supervisory bodies that contribute to better financial performance of companies. Design/methodology/approach: The study involved a quantitative survey using a sample of 33 companies in the highway operating segment and 220 reports from 2010 to 2016. A fixed-effects regression model with panel data was used for analysis. Findings: The results were statistically significant for the board’s independence variables, which confirm the theory that the presence of independents as members of the board positively influences financial management and the company that holds the executive member and chairman of the board positions has a negative effect. The size of the board did not present statistical significance.
DOI: 10.6084/m9.figshare.7046108.v1
title: BOARD OF DIRECTORS: THE PERSPECTIVE OF INDEPENDENTS IN THE PERFORMANCE OF PRIVATE ORGANIZATIONS? EVIDENCES IN BRAZIL

description: ABSTRACT Purpose: The study seeks to verify the influence of the board of directors’ independence on the performance of BM&FBOVESPA listed companies and to analyse which agency conflicts influence the performance of the board of directors. Originality/value: The factor of Brazil being an emerging country which lacks a strict legal system and control factors against corruption in these environments and the public sectors emphasizes the importance of applying the best corporate governance practice code in the main developed countries, reflecting the need for effective supervisory bodies that contribute to better financial performance of companies. Design/methodology/approach: The study involved a quantitative survey using a sample of 33 companies in the highway operating segment and 220 reports from 2010 to 2016. A fixed-effects regression model with panel data was used for analysis. Findings: The results were statistically significant for the board’s independence variables, which confirm the theory that the presence of independents as members of the board positively influences financial management and the company that holds the executive member and chairman of the board positions has a negative effect. The size of the board did not present statistical significance.
DOI: 10.6084/m9.figshare.7046105.v1
title: Morpho-physiological characteristics by sweet potato cultivars as function of irrigation depth

description: Abstract The sweet potato is an alternative energy source, but its sustainability depends on efficient water use. The objective of this study was to evaluate sweet potato morpho-physiological characteristics, and water use efficiency (WUE). Irrigation depths of 50, 75, 100, and 125% of crop evapotranspiration (ETc) were applied. The morpho-physiological indicators, WUE, leaf area index (LAI), leaf water potential, leaf temperature, and leaf chlorophyll index (ICF), were evaluated. The WUE of the sweet potato cultivars increased until the 75% water depth of the ETc. The LAI of these cultivars increased with irrigation depth, with higher values at 100% of the ETc. The leaf water potential of the two sweet potato cultivars was lowest with the lower irrigation depth. Leaf temperature was closer to that of ambient temperatures in treatments with greater irrigation depth. The increase of the WUE with the greater accumulation of dry biomass is due to greater CO2 diffusion by stomata. The reduction in the growth of these plants is due to water stress limiting stomatal conductance, transpiration, leaf growth (LAI) and chlorophyll concentration, proportional to soil moisture conditions. The functional relationship between soil moisture and growth is essential to optimize irrigation management at different growth stages.
DOI: 10.6084/m9.figshare.7046096
title: Structural analysis of a fragmented area in Minas Gerais State, Brazil

description: Abstract The theory of landscape ecology applied to the methods of spatial analysis helps to understand changes in the structure of forest remnants. In view of this theory, the objective of the present study was to analyze the structure of a fragmented area between the years 1979 and 2015 through calculation of landscape metrics for arboreal, shrubby and herbaceous vegetation classes. Vegetation classes were classified with visits to the field, interpretation of aerial photographs from 1979 and supervised classification of Landsat 8 from 2015. The metrics calculated for each class were area and total number of fragments, total edge and average connectivity among the fragments. The analysis of structure found that it changed negatively due to an increase in the number of small fragments, which increased the intensity of edge effects and reduced connectivity between fragments for all classes.
DOI: 10.6084/m9.figshare.7046099
title: Physiology and production of naturally-colored cotton under irrigation strategies using salinized water

description: Abstract: The objective of this work was to evaluate the effects of irrigation management strategies, using low (0.8 dS m-1) and high (9.0 dS m-1) salinity water, on the physiological processes, production variables, and fiber productivity of naturally-colored cotton (Gossypium hirsutum) genotypes during different phenological stages. Three naturally-colored cotton cultivars (BRS Rubi, BRS Topázio, and BRS Safira) were subjected to seven irrigation management strategies, in a 3x7 factorial arrangement, in a randomized complete block design with three replicates. Plants were cultivated in pots in a protected environment. Gas exchange, chlorophyll a fluorescence, fiber production, and productivity and yield variables were evaluated. Salt stress causes greater reductions in gas exchange in natural cotton plants during the production stage. Plume cotton production is not compromised by the use of highly salinized water during the initial developmental stages of naturally-colored cotton.
DOI: 10.6084/m9.figshare.7046096.v1
title: Structural analysis of a fragmented area in Minas Gerais State, Brazil

description: Abstract The theory of landscape ecology applied to the methods of spatial analysis helps to understand changes in the structure of forest remnants. In view of this theory, the objective of the present study was to analyze the structure of a fragmented area between the years 1979 and 2015 through calculation of landscape metrics for arboreal, shrubby and herbaceous vegetation classes. Vegetation classes were classified with visits to the field, interpretation of aerial photographs from 1979 and supervised classification of Landsat 8 from 2015. The metrics calculated for each class were area and total number of fragments, total edge and average connectivity among the fragments. The analysis of structure found that it changed negatively due to an increase in the number of small fragments, which increased the intensity of edge effects and reduced connectivity between fragments for all classes.
DOI: 10.6084/m9.figshare.7046099.v1
title: Physiology and production of naturally-colored cotton under irrigation strategies using salinized water

description: Abstract: The objective of this work was to evaluate the effects of irrigation management strategies, using low (0.8 dS m-1) and high (9.0 dS m-1) salinity water, on the physiological processes, production variables, and fiber productivity of naturally-colored cotton (Gossypium hirsutum) genotypes during different phenological stages. Three naturally-colored cotton cultivars (BRS Rubi, BRS Topázio, and BRS Safira) were subjected to seven irrigation management strategies, in a 3x7 factorial arrangement, in a randomized complete block design with three replicates. Plants were cultivated in pots in a protected environment. Gas exchange, chlorophyll a fluorescence, fiber production, and productivity and yield variables were evaluated. Salt stress causes greater reductions in gas exchange in natural cotton plants during the production stage. Plume cotton production is not compromised by the use of highly salinized water during the initial developmental stages of naturally-colored cotton.
DOI: 10.6084/m9.figshare.7046087
title: Volume equations for Khaya ivorensis A. Chev. plantations in Brazil

description: Abstract African mahogany (Khaya spp.) plantations are in expansion in Brazil and in the world. This fact justifies the need for studies related to its growth and yield. This paper aimed to evaluate the performance of single-entry and double-entry models for estimating merchantable and total volume for Khaya ivorensis plantations before the first thinning (7 years) and expected final cut (15 years). Volume data was from 100 and 46 trees in Minas Gerais and Pará states, respectively, by using an electronic dendrometer (Criterion RD 1000). Observed volumes were calculated by Smalian’s formula. To validate the optical dendrometer, 10 trees were felled and had their volume measured, and compared with the volumes measured indirectly. The results showed that observed and estimated volumes were statistically equal, and that double-entry models were more precise than single-entry models. Schumacher and Hall model was the best equation to estimate merchantable volume for first thinning and for final cut in Minas Gerais stands. Spurr logarithmized model was the best equation to estimate total volume for first thinning and Spurr model for final cut in Pará stands. All chosen equations can be used to quantify merchantable and total volumes of Khaya ivorensis grown under similar conditions.
DOI: 10.6084/m9.figshare.7046093
title: Anatomical modifications of Butia capitata propagated under colored shade nets

description: Abstract The jelly palm plant [Butia capitata (Martius) Beccari] is a native palm of the Cerrado biome used for many purposes in northern Minas Gerais State, Brazil. Dormancy is common in palm seeds, resulting in slow and uneven germination that may take years to complete. Modification in the growth pattern, anatomical parameters, physiological and biochemical characteristics of the plant can be verified due to changes in the light spectrum transmitted through colored shade nets used. Therefore, the objective of this study is to evaluate the effect of colored shade nets on the leaf and root anatomy of the jelly palm plant. The experiment was performed in a completely randomized design, with five treatments, ten replicates and eight plants per replicate, totaling 400 plants. Four colored photo-converter nets with 50% shading and different radiation proportions were employed: white (985 μmol.m-2.s-1), red (327 μmol.m-2.s-1), black (433 μmol.m-2.s-1) and silver (405 μmol.m-2.s-1). The plants cultivated under direct sunlight (1000 μmol.m-2.s-1) were considered as the control group. Leaf and root anatomical analysis was performed on 10 plants per treatment. It is possible to conclude that the colored shade nets caused changes in leaf and root anatomy of the jelly palm plant (Butia capitata).