cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.6152033
title: Democratic administration of public basic education: common dimensions and institutional arrangements shown in regulatory framework of municipal education systems

description: ABSTRACT This article aims to analyze a participatory framework and possible institutional arrangements, as sponsored by municipal education systems to promote democratization of the administration of public basic education. The basis comes from principles of democratic administration and participatory mechanisms established in regulatory foundations of municipal systems of the state of Santa Catarina, which were verified through documents review, in a network research, in order to map of political-institutional conditions to promote participation and democratization of educational administration. The analyses allow the highlighting of common dimensions to these conditions, as well as setup indications of institutional arrangements with the potential to reinforce democratization of public education administration, at system and at school level.
DOI: 10.6084/m9.figshare.6152033.v1
title: Democratic administration of public basic education: common dimensions and institutional arrangements shown in regulatory framework of municipal education systems

description: ABSTRACT This article aims to analyze a participatory framework and possible institutional arrangements, as sponsored by municipal education systems to promote democratization of the administration of public basic education. The basis comes from principles of democratic administration and participatory mechanisms established in regulatory foundations of municipal systems of the state of Santa Catarina, which were verified through documents review, in a network research, in order to map of political-institutional conditions to promote participation and democratization of educational administration. The analyses allow the highlighting of common dimensions to these conditions, as well as setup indications of institutional arrangements with the potential to reinforce democratization of public education administration, at system and at school level.
DOI: 10.6084/m9.figshare.6152030
title: Internet addiction and its correlation with behavioral problems and functional impairments – A cross-sectional study

description: ABSTRACT Objective Evaluate the prevalence of internet addiction (IA) among adolescents, as well as characterize behaviors that are considered to be a risk in this population regarding the use and addiction of the Internet. Methods In this cross-sectional study conducted in one public and one private school 91 adolescents, aged 12 to 16 years old, responded the Internet Addiction Test – Brazilian version (IAT) and Child Behavior Checklist (CBCL). Results The prevalence of internet addiction found was 21%, with no difference between private and public schools. On the group dependent on the Internet, there was a statistically significant correlation with Anxiety/Depression, Withdrawn/Depression, Rule Breaking Behavior and Aggressive Behavior, as well as the syndrome scales Social Problems, Thought Problems and Attention Problems. Conclusion Our study provides evidence of a relationship between internet addiction and behavioral problems among adolescents. As this is a cross-sectional study, we consider that future research is necessary to corroborate our results.
DOI: 10.6084/m9.figshare.6152030.v1
title: Internet addiction and its correlation with behavioral problems and functional impairments – A cross-sectional study

description: ABSTRACT Objective Evaluate the prevalence of internet addiction (IA) among adolescents, as well as characterize behaviors that are considered to be a risk in this population regarding the use and addiction of the Internet. Methods In this cross-sectional study conducted in one public and one private school 91 adolescents, aged 12 to 16 years old, responded the Internet Addiction Test – Brazilian version (IAT) and Child Behavior Checklist (CBCL). Results The prevalence of internet addiction found was 21%, with no difference between private and public schools. On the group dependent on the Internet, there was a statistically significant correlation with Anxiety/Depression, Withdrawn/Depression, Rule Breaking Behavior and Aggressive Behavior, as well as the syndrome scales Social Problems, Thought Problems and Attention Problems. Conclusion Our study provides evidence of a relationship between internet addiction and behavioral problems among adolescents. As this is a cross-sectional study, we consider that future research is necessary to corroborate our results.
DOI: 10.6084/m9.figshare.6152024
title: Rheological Characterization of Bentonite Dispersions with Xanthan for Oil Well Drilling Fluids

description: Shear tests using a coaxial cylinders viscometer were performed in order to determine the rheological and thixotropic properties of xanthan gum dispersions with sodium bentonite in the presence of high salt concentrations of sodium and calcium chlorides. The dispersions rheology with different temperatures and concentrations of NaCl, CaCl2 and xanthan gum were prepared by fixing the bentonite concentration of 1%. The dispersions showed a good fit to power law model through linear regressions with the lowest coefficient of determination value of 0,98. A screening was made initially to decide which independent variables potentially affect the rheological and thixotropic parameters. The independent variables were temperature, the xanthan gum and sodium and calcium chlorides concentrations. Then a full factorial design in duplicate with the remaining variables on the same tracks was performed. The results eliminated calcium chloride as an independent variable and revealed a strong dependence of the rheological and thixotropic parameters with temperature and xanthan gum and NaCl concentrations.
DOI: 10.6084/m9.figshare.6152024.v1
title: Rheological Characterization of Bentonite Dispersions with Xanthan for Oil Well Drilling Fluids

description: Shear tests using a coaxial cylinders viscometer were performed in order to determine the rheological and thixotropic properties of xanthan gum dispersions with sodium bentonite in the presence of high salt concentrations of sodium and calcium chlorides. The dispersions rheology with different temperatures and concentrations of NaCl, CaCl2 and xanthan gum were prepared by fixing the bentonite concentration of 1%. The dispersions showed a good fit to power law model through linear regressions with the lowest coefficient of determination value of 0,98. A screening was made initially to decide which independent variables potentially affect the rheological and thixotropic parameters. The independent variables were temperature, the xanthan gum and sodium and calcium chlorides concentrations. Then a full factorial design in duplicate with the remaining variables on the same tracks was performed. The results eliminated calcium chloride as an independent variable and revealed a strong dependence of the rheological and thixotropic parameters with temperature and xanthan gum and NaCl concentrations.
DOI: 10.6084/m9.figshare.6152021
title: Use of Brazilian Kaolin as a Potential Low-cost Adsorbent for the Removal of Malachite Green from Colored Effluents

description: This study investigated the potential of Brazilian kaolin as a low-cost adsorbent for the removal of Malachite Green (MG) from colored effluents. The morphology, chemical structure and surface properties of the adsorbent were investigated by characterization techniques such as X-ray diffraction, N2 adsorption-desorption isotherms, Fourier transform infrared spectroscopy, X-ray fluorescence spectrometry, scanning electron microscopy, thermogravimetric analysis and particle size distribution. A possible technological application of raw kaolin is the MG removal from aqueous media, which was investigated using batch adsorption experiments. The adsorption kinetics was studied using the pseudo-first order, pseudo-second order and Elovich models. The adsorption isotherms were studied using the Langmuir, Freundlich and Sips models. The Elovich model was the more adequate to represent the adsorption kinetic, while the equilibrium was well represented by the Langmuir model. The maximum adsorption capacity, at pH of 6.3 and temperature of 25ºC, was 128 mg g-1, and this satisfactory result may be associated with some adsorbent properties. Therefore, the results revealed that raw kaolin can be utilized as a promising low-cost adsorbent to remove MG from colored effluents.
DOI: 10.6084/m9.figshare.6152021.v1
title: Use of Brazilian Kaolin as a Potential Low-cost Adsorbent for the Removal of Malachite Green from Colored Effluents

description: This study investigated the potential of Brazilian kaolin as a low-cost adsorbent for the removal of Malachite Green (MG) from colored effluents. The morphology, chemical structure and surface properties of the adsorbent were investigated by characterization techniques such as X-ray diffraction, N2 adsorption-desorption isotherms, Fourier transform infrared spectroscopy, X-ray fluorescence spectrometry, scanning electron microscopy, thermogravimetric analysis and particle size distribution. A possible technological application of raw kaolin is the MG removal from aqueous media, which was investigated using batch adsorption experiments. The adsorption kinetics was studied using the pseudo-first order, pseudo-second order and Elovich models. The adsorption isotherms were studied using the Langmuir, Freundlich and Sips models. The Elovich model was the more adequate to represent the adsorption kinetic, while the equilibrium was well represented by the Langmuir model. The maximum adsorption capacity, at pH of 6.3 and temperature of 25ºC, was 128 mg g-1, and this satisfactory result may be associated with some adsorbent properties. Therefore, the results revealed that raw kaolin can be utilized as a promising low-cost adsorbent to remove MG from colored effluents.
DOI: 10.6084/m9.figshare.6152015
title: Spark Plasma Sintering of a Hard Metal Powder Obtained from Hard Metal Scrap

description: Spark plasma sintering is used to consolidate a WC-Co powder produced from milled discharged hard metal cutting inserts. The powder was mixed to 10%wt Co powder and spark plasma sintered (SPS) under 80Mpa pressure, at 1200ºC with heating rate of 160ºC/min. A reference alloy was prepared with a commercial WC powder and 10%wt. Co under the same conditions. The structures of both alloys were investigated by means of scanning electron microscopy and Vickers hardness. The results show structures with densities and hardness at the same level. SPS can be used to produce hard metal pieces directly from scrap powder without any prior chemical and thermal treatment.
DOI: 10.6084/m9.figshare.6152006
title: Creep Parameters and Dislocation Substructure in AISI 316 Austenitic Stainless Steel From 600ºC to 800ºC

description: Stainless steels are well known by their corrosion resistance. The austenitic types, in particular, are also applied as structural components in engineering systems operating at high temperatures such as nuclear reactors, petrochemical furnaces and turbines. For these applications operational temperatures may go up to 800ºC. Under constant load applications the main mechanism of failure, which would limit the material's life, is creep. In the present work creep parameters were evaluated in the high temperature interval of 600 to 800ºC for an AISI 316 austenitic stainless steel. Dislocation substructures were observed by transmission electron microscopy in creep ruptured specimens. Two distinct mechanisms of dynamic strain aging and dynamic recovery associated with different values for the power law exponent n and the Arrhenius activation energy Q for creep were verified below and above 700ºC, respectively.
DOI: 10.6084/m9.figshare.6152000
title: Multiple stresses on the oxidative metabolism of sugarcane varieties

description: ABSTRACT: The exposure of plants to multiple stress conditions can cause over production of reactive oxygen species promoting an imbalance in the redox system. The aim of this study was to examine the antioxidant response from varieties of sugarcane under adverse conditions, to understand the defense mechanisms of tolerant and sensitive genotypes. Micropropagated sugarcane of six genotypes, RB966928, RB98710, RB855453, RB99395, RB867515, and RB855156, were subjected to isolated action of high-temperature stress and a combination of water and saline stress, and effects were evaluated. Activities of enzymes such as superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX), as well as stress indicators such as lipid peroxidation (MDA content) and hydrogen peroxide (H2O2) content were evaluated. The RB867515 variety showed synchrony between the enzymatic activity and ROS regulation and detoxification, in the plant cell under environmental stress situations, thereby ensuring the maintenance of the relative water content without increment of lipid peroxidation; and consequently, the maintenance of physiological processes and plant growth. These results indicated that lipid peroxidation associated with relative water content can be good biochemical markers of sensitivity to multiple stresses in sugarcane.
DOI: 10.6084/m9.figshare.6152000.v1
title: Multiple stresses on the oxidative metabolism of sugarcane varieties

description: ABSTRACT: The exposure of plants to multiple stress conditions can cause over production of reactive oxygen species promoting an imbalance in the redox system. The aim of this study was to examine the antioxidant response from varieties of sugarcane under adverse conditions, to understand the defense mechanisms of tolerant and sensitive genotypes. Micropropagated sugarcane of six genotypes, RB966928, RB98710, RB855453, RB99395, RB867515, and RB855156, were subjected to isolated action of high-temperature stress and a combination of water and saline stress, and effects were evaluated. Activities of enzymes such as superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX), as well as stress indicators such as lipid peroxidation (MDA content) and hydrogen peroxide (H2O2) content were evaluated. The RB867515 variety showed synchrony between the enzymatic activity and ROS regulation and detoxification, in the plant cell under environmental stress situations, thereby ensuring the maintenance of the relative water content without increment of lipid peroxidation; and consequently, the maintenance of physiological processes and plant growth. These results indicated that lipid peroxidation associated with relative water content can be good biochemical markers of sensitivity to multiple stresses in sugarcane.
DOI: 10.6084/m9.figshare.6151997
title: Physicochemical Characterization of Pulverized Phyllite Rock for Geopolymer Resin Synthesis

description: Geopolymeric materials have some unique properties such as early-high compressive strength, durability, resistance to acids and sulfates, ability to immobilize toxic and radioactive compounds, low porosity and high temperature resistance. These materials are strategic for sustainable development and are a suitable alternative to Portland cement. The use of phyllite as a geopolymer precursor is encouraged by its abundance, low cost, and the fact that it is already applied in ceramic industries as a kaolin substitute. The objective of this paper is the physicochemical characterization of geopolymeric resin using two pulverized phyllite rocks as precursors with STEM, XRD and XRF techniques. It was found that both phyllite rocks studied have a high quartz content of approximately 50% (weight), which have a "filler" function in the microstructure of the resin helping stabilize residual tensions after curing. Kaolinite and muscovite minerals are present in up to 40% (weight) and are responsible for the high compressive strength of the geopolymer resins.
DOI: 10.6084/m9.figshare.6151997.v1
title: Physicochemical Characterization of Pulverized Phyllite Rock for Geopolymer Resin Synthesis

description: Geopolymeric materials have some unique properties such as early-high compressive strength, durability, resistance to acids and sulfates, ability to immobilize toxic and radioactive compounds, low porosity and high temperature resistance. These materials are strategic for sustainable development and are a suitable alternative to Portland cement. The use of phyllite as a geopolymer precursor is encouraged by its abundance, low cost, and the fact that it is already applied in ceramic industries as a kaolin substitute. The objective of this paper is the physicochemical characterization of geopolymeric resin using two pulverized phyllite rocks as precursors with STEM, XRD and XRF techniques. It was found that both phyllite rocks studied have a high quartz content of approximately 50% (weight), which have a "filler" function in the microstructure of the resin helping stabilize residual tensions after curing. Kaolinite and muscovite minerals are present in up to 40% (weight) and are responsible for the high compressive strength of the geopolymer resins.
DOI: 10.6084/m9.figshare.6151994
title: Biocorrosion on Surface of ASTM A283 Carbon Steel, Exposed in Diesel S10 and Tap Water

description: This paper sets out to evaluate the corrosion and biocorrosion of carbon steel ASTM A283 exposed to a Diesel S10 oil/tap water system under static conditions for 90 days. The following analyzes were performed: physico-chemical in tap water, sulfur content in Diesel S10 and quantification of sessile microorganisms in the biofilm formed on the metal. To monitor the corrosion process, mass loss, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), confocal laser microscopy and X-ray diffraction (XRD) were performed. There were changes in the composition of the medium, correlated with the formation of corrosion and biofilm products. There was biodegradation of the fuel, which in contact with water influenced the development of microorganisms. Moreover, the corrosion rate was classified as moderate, the main form of corrosion being seen to be local alveolar corrosion. Therefore, the results revealed that water in diesel oil can be an aggravating factor in the process of corrosion and biocorrosion.
DOI: 10.6084/m9.figshare.6151994.v1
title: Biocorrosion on Surface of ASTM A283 Carbon Steel, Exposed in Diesel S10 and Tap Water

description: This paper sets out to evaluate the corrosion and biocorrosion of carbon steel ASTM A283 exposed to a Diesel S10 oil/tap water system under static conditions for 90 days. The following analyzes were performed: physico-chemical in tap water, sulfur content in Diesel S10 and quantification of sessile microorganisms in the biofilm formed on the metal. To monitor the corrosion process, mass loss, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), confocal laser microscopy and X-ray diffraction (XRD) were performed. There were changes in the composition of the medium, correlated with the formation of corrosion and biofilm products. There was biodegradation of the fuel, which in contact with water influenced the development of microorganisms. Moreover, the corrosion rate was classified as moderate, the main form of corrosion being seen to be local alveolar corrosion. Therefore, the results revealed that water in diesel oil can be an aggravating factor in the process of corrosion and biocorrosion.
DOI: 10.6084/m9.figshare.6151991
title: Remembering the past – studies on evolution done by the genetics group at Universidade Federal do Rio Grande do Sul (UFRGS)

description: Abstract After a brief introduction about the factors that are involved in science development, and world and Brazilian evolutionary genetics, the studies developed in Porto Alegre in this area were reviewed. Four periods in the development of this group were distinguished: (a) Origins and first expansion (1949-1961); (b) Second expansion (1962-1988); (c) Third expansion (1989-2001); and (d) The last 15 years (2002-present). The international Porto Alegre Biological Evolution Workshops (PABEWs), with five biannual events from 2007 o 2015, were also mentioned. The final message stressed the importance of the maintenance of this and other Brazilian groups of research through adequate finance and recognition.
DOI: 10.6084/m9.figshare.6151988
title: Evolution of DNMT2 in drosophilids: Evidence for positive and purifying selection and insights into new protein (pathways) interactions

description: Abstract The DNA methyltransferase 2 (DNMT2) protein is the most conserved member of the DNA methyltransferase family. Nevertheless, its substrate specificity is still controversial and elusive. The genomic role and determinants of DNA methylation are poorly understood in invertebrates, and several mechanisms and associations are suggested. In Drosophila, the only known DNMT gene is Dnmt2. Here we present our findings from a wide search for Dnmt2 homologs in 68 species of Drosophilidae. We investigated its molecular evolution, and in our phylogenetic analyses the main clades of Drosophilidae species were recovered. We tested whether the Dnmt2 has evolved neutrally or under positive selection along the subgenera Drosophila and Sophophora and investigated positive selection in relation to several physicochemical properties. Despite of a major selective constraint on Dnmt2, we detected six sites under positive selection. Regarding the DNMT2 protein, 12 sites under positive-destabilizing selection were found, which suggests a selection that favors structural and functional shifts in the protein. The search for new potential protein partners with DNMT2 revealed 15 proteins with high evolutionary rate covariation (ERC), indicating a plurality of DNMT2 functions in different pathways. These events might represent signs of molecular adaptation, with molecular peculiarities arising from the diversity of evolutionary histories experienced by drosophilids.
DOI: 10.6084/m9.figshare.6151991.v1
title: Remembering the past – studies on evolution done by the genetics group at Universidade Federal do Rio Grande do Sul (UFRGS)

description: Abstract After a brief introduction about the factors that are involved in science development, and world and Brazilian evolutionary genetics, the studies developed in Porto Alegre in this area were reviewed. Four periods in the development of this group were distinguished: (a) Origins and first expansion (1949-1961); (b) Second expansion (1962-1988); (c) Third expansion (1989-2001); and (d) The last 15 years (2002-present). The international Porto Alegre Biological Evolution Workshops (PABEWs), with five biannual events from 2007 o 2015, were also mentioned. The final message stressed the importance of the maintenance of this and other Brazilian groups of research through adequate finance and recognition.