cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.6151586.v1
title: Estimation of the traction power of agricultural tractors from dynamometric tests

description: ABSTRACT: The objective of this research was to predict, from dynamometric tests, the traction performance of agricultural tractors, without the need to employ the standard official tests carried out on concrete tracks. The evaluations were conducted at the experimental area of the Universidade Federal de Santa Maria, where an instrumented agricultural tractor was subjected to dynamic field traction tests and static tests in the laboratory, using an eddy currents dynamometer. It can be verified through the correlation analysis between the values obtained and the estimated values that, based on the prediction equations, a high correlation (r² = 0.99) was obtained between the power observed in the field and the estimated power obtained using dynamometric tests. Based on the analysis of the results obtained in this study, it can be stated that the traction performance of an agricultural tractor can be estimated from dynamometric tests. We concluded that the dynamic field tests can be replaced by static tests carried out in laboratories, which are generally less expensive.
DOI: 10.6084/m9.figshare.6151583
title: Effect of the T6 Heat Treatment on Microhardness of a Directionally Solidified Aluminum-Based 319 Alloy

description: Aluminum alloys of the ANSI series 319 present Si and Cu as the main alloying elements and the mechanical strength of these alloys can be improved by the precipitation of the metastable Al2Cu phase during the ageing heat treatment. In this paper, the Al-5.5wt.%Si-3wt.%Cu alloy was elaborated and solidified in a water-cooled horizontal directional solidification device. The as-cast ingot was subjected to the precipitation hardening heat treatment (T6 heat treatment), which consisted of: solution for 5 h at 490°C±2°C, followed by quenching in water at 60°C±2°C and ageing for 3 h at 155°C±2°C, and cooling-air. Secondary dendrite arm spacing (λ2) measurements were carried out before and after T6 heat treatment. The mechanical strength of the alloy was investigated by the microhardness test. It has been found that the heat treatment did not influence the λ2 values, however, highest HV values have been observed for the heat-treated samples.
DOI: 10.6084/m9.figshare.6151583.v1
title: Effect of the T6 Heat Treatment on Microhardness of a Directionally Solidified Aluminum-Based 319 Alloy

description: Aluminum alloys of the ANSI series 319 present Si and Cu as the main alloying elements and the mechanical strength of these alloys can be improved by the precipitation of the metastable Al2Cu phase during the ageing heat treatment. In this paper, the Al-5.5wt.%Si-3wt.%Cu alloy was elaborated and solidified in a water-cooled horizontal directional solidification device. The as-cast ingot was subjected to the precipitation hardening heat treatment (T6 heat treatment), which consisted of: solution for 5 h at 490°C±2°C, followed by quenching in water at 60°C±2°C and ageing for 3 h at 155°C±2°C, and cooling-air. Secondary dendrite arm spacing (λ2) measurements were carried out before and after T6 heat treatment. The mechanical strength of the alloy was investigated by the microhardness test. It has been found that the heat treatment did not influence the λ2 values, however, highest HV values have been observed for the heat-treated samples.
DOI: 10.6084/m9.figshare.6151580
title: Phylogeographic analyses of the pampas cat (Leopardus colocola; Carnivora, Felidae) reveal a complex demographic history

description: Abstract The pampas cat is a small felid that occurs in open habitats throughout much of South America. Previous studies have revealed intriguing patterns of morphological differentiation and genetic structure among its populations, as well as molecular evidence for hybridization with the closely related L. tigrinus. Here we report phylogeographic analyses encompassing most of its distribution (focusing particularly on Brazilian specimens, which had been poorly sampled in previous studies), using a novel dataset comprising 2,143 bp of the mitogenome, along with previously reported mtDNA sequences. Our data revealed strong population strutucture and supported a west-to-east colonization process in this species’ history. We detected two population expansion events, one older (ca. 200 thousand years ago [kya]) in western South America and another more recent (ca. 60-50 kya) in eastern areas, coinciding with the expansion of savanna environments in Brazil. Analyses including L. tigrinus individuals bearing introgressed mtDNA from L. colocola showed a complete lack of shared haplotypes between species, indicating that their hybridization was ancient. Finally, we observed a close relationship between Brazilian/Uruguayan L. colocola haplotypes and those sampled in L. tigrinus, indicating that their hybridization was likely related to the demographic expansion of L. colocola into eastern South America.
DOI: 10.6084/m9.figshare.6151580.v1
title: Phylogeographic analyses of the pampas cat (Leopardus colocola; Carnivora, Felidae) reveal a complex demographic history

description: Abstract The pampas cat is a small felid that occurs in open habitats throughout much of South America. Previous studies have revealed intriguing patterns of morphological differentiation and genetic structure among its populations, as well as molecular evidence for hybridization with the closely related L. tigrinus. Here we report phylogeographic analyses encompassing most of its distribution (focusing particularly on Brazilian specimens, which had been poorly sampled in previous studies), using a novel dataset comprising 2,143 bp of the mitogenome, along with previously reported mtDNA sequences. Our data revealed strong population strutucture and supported a west-to-east colonization process in this species’ history. We detected two population expansion events, one older (ca. 200 thousand years ago [kya]) in western South America and another more recent (ca. 60-50 kya) in eastern areas, coinciding with the expansion of savanna environments in Brazil. Analyses including L. tigrinus individuals bearing introgressed mtDNA from L. colocola showed a complete lack of shared haplotypes between species, indicating that their hybridization was ancient. Finally, we observed a close relationship between Brazilian/Uruguayan L. colocola haplotypes and those sampled in L. tigrinus, indicating that their hybridization was likely related to the demographic expansion of L. colocola into eastern South America.
DOI: 10.6084/m9.figshare.6151577
title: High Temperature Plastic Instability and Dynamic Strain Aging in the Tensile Behavior of AISI 316 Stainless Steel

description: The plastic instability in the stress-strain curve and work hardening of a type AISI 316 austenitic stainless steel was investigated in the high temperature range of 150°C to 800°C for two strain rates. The results indicate the occurrence of plastic instability and serrations between 200°C and 650°C with peaks in both the tensile strength and work hardening rate. These plastic instability/serrations are associated with dynamic strain aging behavior. As a consequence, within the temperature interval of plastic instability, a negative value for the strain rate sensitivity was found. Based on the activation energy, it is proposed that a mechanism of substitutional solute atoms interaction with dislocations be responsible for the plastic instability.
DOI: 10.6084/m9.figshare.6151574
title: The influence of allopurinol and post-conditioning on lung injuries induced by lower-limb ischemia and reperfusion in Wistar rats

description: Abstract Purpose: To analyze the effects of allopurinol and of post-conditioning on lung injuries induced by lower-limb ischemia and reperfusion. Methods: Thirty rats were used. They were divided in 5 groups: (1) group A: abdominal aortic dissection only, (2) group B: ischemia and reperfusion, (3) group C: administered allopurinol (100mg/Kg) a few hours before procedure, (4) group D: post-conditioned and (5) group E: administered allopurinol and post-conditioned. With the exception of group A, all groups were submitted to infrarenal aortic ischemia for 2 hours, and reperfusion for 72 hours. After euthanasia, lungs were removed for histological analysis. They were graded under two scores: pulmonary injury (neutrophil infiltration, interstitial edema, vascular congestion, and destruction of lung architecture) and lymphocytic score (neutrophil infiltration, lymphoid aggregate and secondary follicle). Results: On the pulmonary injury score, the degree of injury was smaller than in groups D and E, when compared to group B, p&lt;0.05. Group C did not obtain the same result (p&gt;0,05). On the lymphocytic score, there was no statistic difference among groups, p&gt;0.05. Conclusion: Both post-conditioning and the combination of allopurinol and post-conditioning were effective in remote lung protection induced by lower-limbs I/R. When used in isolation, allopurinol showed no protective effect.
DOI: 10.6084/m9.figshare.6151574.v1
title: The influence of allopurinol and post-conditioning on lung injuries induced by lower-limb ischemia and reperfusion in Wistar rats

description: Abstract Purpose: To analyze the effects of allopurinol and of post-conditioning on lung injuries induced by lower-limb ischemia and reperfusion. Methods: Thirty rats were used. They were divided in 5 groups: (1) group A: abdominal aortic dissection only, (2) group B: ischemia and reperfusion, (3) group C: administered allopurinol (100mg/Kg) a few hours before procedure, (4) group D: post-conditioned and (5) group E: administered allopurinol and post-conditioned. With the exception of group A, all groups were submitted to infrarenal aortic ischemia for 2 hours, and reperfusion for 72 hours. After euthanasia, lungs were removed for histological analysis. They were graded under two scores: pulmonary injury (neutrophil infiltration, interstitial edema, vascular congestion, and destruction of lung architecture) and lymphocytic score (neutrophil infiltration, lymphoid aggregate and secondary follicle). Results: On the pulmonary injury score, the degree of injury was smaller than in groups D and E, when compared to group B, p&lt;0.05. Group C did not obtain the same result (p&gt;0,05). On the lymphocytic score, there was no statistic difference among groups, p&gt;0.05. Conclusion: Both post-conditioning and the combination of allopurinol and post-conditioning were effective in remote lung protection induced by lower-limbs I/R. When used in isolation, allopurinol showed no protective effect.
DOI: 10.6084/m9.figshare.6151568
title: Fracture Modes of AISI Type 302 Stainless Steel Under Metastable Plastic Deformation

description: Martensitic transformation can be induced by plastic deformation in metastable iron-based alloys, such as stainless steels containing limited amounts of C, Ni and Cr. This transformation takes place at the temperature range from Ms and Md, usually at relatively lower temperature values. The transformed martensite has been associated with maximum ultimate strength and relatively high ductility. In the present work, the tensile fracture characteristics of a metastable AISI type 302 stainless steel was properties were compared to those of a stable AISI type 310 austenitic stainless steel. It was found that in 302 steel, its high degree of metastability and dilute dispersion of inclusions result in higher strength and complex modes of fracture, one of which consisting of martensite surrounding globular inclusions.
DOI: 10.6084/m9.figshare.6151565
title: A Comparative Study of Cartesian and Delta 3D Printers on Producing PLA Parts

description: The additive manufacturing processes emerged at the end of the last century and became popular by low-cost 3D printers. The most used printers work on a cartesian configuration, but recently were launched delta machines. These 3D printers use a more complex control system due to their trajectories generation but may present some advantages over the cartesian configuration. To increase the knowledge about additive manufacturing, a comparative study with cartesian and delta printers was performed to evaluate the performance on printing a testing part. Three samples were produced in each printer and compared based on surface quality, manufacturing time, mass and dimensional measurement. The printed objects were 3D scanned for comparing the digitized geometry by aligning the point cloud generated to its virtual 3D model. The parts produced in delta printer obtained better surface quality, while cartesian printer provided better dimensional accuracy. The results also showed that the variation of the mass and time to produce the parts were not significant.
DOI: 10.6084/m9.figshare.6151565.v1
title: A Comparative Study of Cartesian and Delta 3D Printers on Producing PLA Parts

description: The additive manufacturing processes emerged at the end of the last century and became popular by low-cost 3D printers. The most used printers work on a cartesian configuration, but recently were launched delta machines. These 3D printers use a more complex control system due to their trajectories generation but may present some advantages over the cartesian configuration. To increase the knowledge about additive manufacturing, a comparative study with cartesian and delta printers was performed to evaluate the performance on printing a testing part. Three samples were produced in each printer and compared based on surface quality, manufacturing time, mass and dimensional measurement. The printed objects were 3D scanned for comparing the digitized geometry by aligning the point cloud generated to its virtual 3D model. The parts produced in delta printer obtained better surface quality, while cartesian printer provided better dimensional accuracy. The results also showed that the variation of the mass and time to produce the parts were not significant.
DOI: 10.6084/m9.figshare.6151562
title: Synthesis of MgAl2O4 by Gelatin Method: Effect of Temperature and Time of Calcination in Crystalline Structure

description: Magnesium aluminate can be obtained by the methods: ceramic method, sol-gel, co-precipitation, hydrothermal and combustion. However, this work presents a simple and low cost route to obtain MgAl2O4 through the gelatin method. The main objective was to use gelatin as an organic precursor and to verify the influence of temperature and time of calcination on the structural and morphological properties of obtained materials. Al and Mg nitrates were used as metal precursors with Al/Mg = 2 ratio. Samples were calcined as follows: 700 ºC, 900 ºC and 1100 ºC during 2 and 4 h. The powders were characterized by TGA, XRD and SEM. A single phase material with a crystallinity of 39.18 - 90.40% and crystallite size in the range of 12.4 to 55.5 nm was obtained. The materials exhibited morphology in the form of plates and small agglomerates. It was found that increasing temperature and time of calcination favored the growth of crystallites and increased crystallinity.
DOI: 10.6084/m9.figshare.6151562.v1
title: Synthesis of MgAl2O4 by Gelatin Method: Effect of Temperature and Time of Calcination in Crystalline Structure

description: Magnesium aluminate can be obtained by the methods: ceramic method, sol-gel, co-precipitation, hydrothermal and combustion. However, this work presents a simple and low cost route to obtain MgAl2O4 through the gelatin method. The main objective was to use gelatin as an organic precursor and to verify the influence of temperature and time of calcination on the structural and morphological properties of obtained materials. Al and Mg nitrates were used as metal precursors with Al/Mg = 2 ratio. Samples were calcined as follows: 700 ºC, 900 ºC and 1100 ºC during 2 and 4 h. The powders were characterized by TGA, XRD and SEM. A single phase material with a crystallinity of 39.18 - 90.40% and crystallite size in the range of 12.4 to 55.5 nm was obtained. The materials exhibited morphology in the form of plates and small agglomerates. It was found that increasing temperature and time of calcination favored the growth of crystallites and increased crystallinity.
DOI: 10.6084/m9.figshare.6151559
title: Fracture Properties of Geopolymer Concrete Based on Metakaolin, Fly Ash and Rice Rusk Ash

description: Geopolymers are exclusively mineral nature and are considered an alternative to materials based on Portland clinker, whose production accounts for about 5% of anthropogenic CO2 emissions in the world. The geopolymer cement concrete (GCC) may be prepared from natural oxide-aluminosilicates such as metakaolin (MK), or synthetic, such as fly ash (FA) together with active silica contained in the rice husk ash (RHA). The fracture properties of the Portland cement concrete (PCC) with 25 MPa and 50 MPa, and of three different geopolymeric concretes with the same strength Classes were determined for comparative analysis. The aim of this study is to provide support to begin the use of geopolymers in the reinforced concrete precasting Industry. Three-point bending tests of notched beams with a/d (notch depth/beam depth) of 0.5 from RILEM TC80-FMT Recommendations were used to determine the critical values of K, G, R and J-integral for crack propagation under mode I. The results showed that the geopolymeric concretes exhibit similar mechanical behavior and fracture properties higher that those determined in PCC for the same strength class.
DOI: 10.6084/m9.figshare.6151559.v1
title: Fracture Properties of Geopolymer Concrete Based on Metakaolin, Fly Ash and Rice Rusk Ash

description: Geopolymers are exclusively mineral nature and are considered an alternative to materials based on Portland clinker, whose production accounts for about 5% of anthropogenic CO2 emissions in the world. The geopolymer cement concrete (GCC) may be prepared from natural oxide-aluminosilicates such as metakaolin (MK), or synthetic, such as fly ash (FA) together with active silica contained in the rice husk ash (RHA). The fracture properties of the Portland cement concrete (PCC) with 25 MPa and 50 MPa, and of three different geopolymeric concretes with the same strength Classes were determined for comparative analysis. The aim of this study is to provide support to begin the use of geopolymers in the reinforced concrete precasting Industry. Three-point bending tests of notched beams with a/d (notch depth/beam depth) of 0.5 from RILEM TC80-FMT Recommendations were used to determine the critical values of K, G, R and J-integral for crack propagation under mode I. The results showed that the geopolymeric concretes exhibit similar mechanical behavior and fracture properties higher that those determined in PCC for the same strength class.
DOI: 10.6084/m9.figshare.6151553
title: Biodegradation in Soil of the PHB/Wood Flour (80/20) and PHB/Sisal Fiber (80/20) Tubes

description: This paper presents the results of a study that aimed to monitor and evaluate biodegradation in soil, by the mass loss and the mechanical properties of plastic tubes. For this work, there were extruded and injected plastic tubes made of biodegradable polymer poly(hydroxybutyrate) - (PHB) and composite PHB/Wood Flour and PHB/Sisal Fiber, both with 20% fiber. There were used three biodegradation test devices for 30, 60 and 90 days. At the end of each test, the biodegraded samples were taken from soil, washed thoroughly with water, dried and weighed to evaluate the mass loss. Mechanical properties were evaluated using flexural tests before and after biodegradation in soil. Based on the results, it was observed that all the studied tubes lost mass over the biodegradation test, and the tubes of biodegradable composites lost more weight than pure PHB.
DOI: 10.6084/m9.figshare.6151553.v1
title: Biodegradation in Soil of the PHB/Wood Flour (80/20) and PHB/Sisal Fiber (80/20) Tubes

description: This paper presents the results of a study that aimed to monitor and evaluate biodegradation in soil, by the mass loss and the mechanical properties of plastic tubes. For this work, there were extruded and injected plastic tubes made of biodegradable polymer poly(hydroxybutyrate) - (PHB) and composite PHB/Wood Flour and PHB/Sisal Fiber, both with 20% fiber. There were used three biodegradation test devices for 30, 60 and 90 days. At the end of each test, the biodegraded samples were taken from soil, washed thoroughly with water, dried and weighed to evaluate the mass loss. Mechanical properties were evaluated using flexural tests before and after biodegradation in soil. Based on the results, it was observed that all the studied tubes lost mass over the biodegradation test, and the tubes of biodegradable composites lost more weight than pure PHB.
DOI: 10.6084/m9.figshare.6151550
title: Construction of a biological rhythm assessment scale for children

description: Abstract Introduction Biological rhythm is associated with the level of alertness, cognitive performance and mood of the individuals. Its regularity is essential to preserve good health and quality of life. Objective To present the steps for the construction of the scale entitled Biological Rhythm Interview of Assessment in Neuropsychiatry – Kids (BRIAN-K), designed to measure biological rhythm disruptions in Brazilian children and adolescents. Methods Items were developed following the adult version of the scale. Analysis of the psychometric characteristics of the scale was based on the responses of 373 parents/caregivers of school age children (7 and 8 years old). Results A theoretical model of 17 items with the purpose of evaluating four domains (sleep, activities, social rhythm and eating pattern) was determined using exploratory factor analysis (EFA) and via identification of a general factor. The psychometric properties of the BRIAN-K showed favorable properties. Conclusion Only two items needed to be rewritten. Further studies are needed to investigate the instrument's adequacy to different age groups and additional evidence of validity and reliability.
DOI: 10.6084/m9.figshare.6151550.v1
title: Construction of a biological rhythm assessment scale for children

description: Abstract Introduction Biological rhythm is associated with the level of alertness, cognitive performance and mood of the individuals. Its regularity is essential to preserve good health and quality of life. Objective To present the steps for the construction of the scale entitled Biological Rhythm Interview of Assessment in Neuropsychiatry – Kids (BRIAN-K), designed to measure biological rhythm disruptions in Brazilian children and adolescents. Methods Items were developed following the adult version of the scale. Analysis of the psychometric characteristics of the scale was based on the responses of 373 parents/caregivers of school age children (7 and 8 years old). Results A theoretical model of 17 items with the purpose of evaluating four domains (sleep, activities, social rhythm and eating pattern) was determined using exploratory factor analysis (EFA) and via identification of a general factor. The psychometric properties of the BRIAN-K showed favorable properties. Conclusion Only two items needed to be rewritten. Further studies are needed to investigate the instrument's adequacy to different age groups and additional evidence of validity and reliability.