cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.14278865.v1
title: A survey of parabens in commercial baby wipes from Brazil and estimation of daily exposure

description: Several studies have shown endocrine-disrupting effects of parabens. Parabens are a group of antimicrobials used as preservatives in a wide variety of products, mainly in personal care products. However, little information is available regarding the occurrence of parabens in baby products. In this study, the concentrations of five commonly used parabens, methyl-, ethyl-, propyl-, butyl- and, benzyl-paraben in 50 Brazilian baby wet wipes were analyzed by liquid chromatography coupled to mass spectrometry. All samples contained parabens, and the total concentrations ranged from 16 to 332,470 ng g-1 (geometric mean: 5344 ng g-1). Methyl-paraben, ethyl-paraben, propyl-paraben, and butyl-paraben were found in &gt;65% of the samples. 24 out of 50 samples exceed the permitted value of 0.4 % for methyl-paraben for their use in personal care products. Although, propyl-paraben and butyl-paraben are forbidden in cosmetic products designed for application on the nappy area of children under three years of age, the detection rate of them were 94 and 70 %, respectively. Based on the measured concentrations and use frequency of baby wipes the estimated daily intake of parabens was calculated. The median estimated daily intake values of total concentrations of parabens for babies of one year old was 391 ng kg-1 bw day-1. In conclusion, babies and children may be exposed to high levels of parabens through use of baby wipes. It is also worth to mention that two forbidden parabens were frequently detected.
DOI: 10.6084/m9.figshare.14278862
title: CeαMn1-αO2 catalysts supported over γ-Al2O3 prepared by modified redox-coprecipitation methods for n-hexane combustion

description: A series of CeαMn1-αO2 catalysts supported on γ-alumina with various molar concentrations of Ce (α, from 0 to 0.90) was synthesized by coprecipitation, applying two different precipitating agents, namely, sodium hydroxide (method 1) and sodium carbonate (method 2), with the use of sodium permanganate as a redox agent for precipitation. XRD profiles of the supported samples revealed the predominant abundance of a typical fluorite crystalline structure. TPR thermograms of supported samples were displaced towards lower temperatures with increasing Mn concentration, in contrast with the bulk samples. The supported Ce-Mn samples exhibited a greater performance in n-hexane elimination than did the corresponding simple oxides. The sample Ce0.33Mn0.67O2 obtained by method 2 presented the best activity, probably due to the enrichment of Ce4+, Mn3+ and Mn4+ surface species, an excess of superficial oxygen species and an easy reducibility as well as the lowest apparent activation energy.
DOI: 10.6084/m9.figshare.14278855.v1
title: CONSTRUCTION OF MINI OVEN FOR THERMAL FUNCTIONALIZATION OF MONOLITHIC STATIONARY PHASES

description: The present work describes a mini oven built to be applied in the preparation of monolithic stationary phase through the thermal polymerization approach. The developed device was successfully tested for functionalization of monolithic stationary phase in the internal surface of the silica capillary column fused with gold nanoparticles.
DOI: 10.6084/m9.figshare.14278862.v1
title: CeαMn1-αO2 catalysts supported over γ-Al2O3 prepared by modified redox-coprecipitation methods for n-hexane combustion

description: A series of CeαMn1-αO2 catalysts supported on γ-alumina with various molar concentrations of Ce (α, from 0 to 0.90) was synthesized by coprecipitation, applying two different precipitating agents, namely, sodium hydroxide (method 1) and sodium carbonate (method 2), with the use of sodium permanganate as a redox agent for precipitation. XRD profiles of the supported samples revealed the predominant abundance of a typical fluorite crystalline structure. TPR thermograms of supported samples were displaced towards lower temperatures with increasing Mn concentration, in contrast with the bulk samples. The supported Ce-Mn samples exhibited a greater performance in n-hexane elimination than did the corresponding simple oxides. The sample Ce0.33Mn0.67O2 obtained by method 2 presented the best activity, probably due to the enrichment of Ce4+, Mn3+ and Mn4+ surface species, an excess of superficial oxygen species and an easy reducibility as well as the lowest apparent activation energy.
DOI: 10.6084/m9.figshare.14278871
title: The use of the thalidomide case in the construction of meaning in higher education chemistry classes

description: Studies conducted in the field of education have, in many cases, highlighted the little insertion of teaching and learning theories in Natural Sciences classes, in Higher Education. We developed this study to analyze how Chemistry professors take ownership of a historical case to explain the concepts they develop in their classes. To do so, we analyzed this record of undergraduate classes, at times when professors related pedagogical link-making to the future field of work of the students, using the “Thalidomide case.” We realized that, by showing the importance of studies involving chirality and related concepts, the students’ attention to the content seems to have increased significantly, which expands the possibilities of construction of meaning. Thus, we argue that the pedagogical link-making can significantly contribute to students’ knowledge.
DOI: 10.6084/m9.figshare.14278868
title: Air pollutants emissions in real conditions of asphalt paving. particulate matter (pm), black carbon (bc) and polycyclic aromatic hydrocarbons (pahs)

description: Intensive use of asphalt generates pollutants into the atmosphere which are harmful to the environment and worrying for occupational health. The application of asphalt products leads to emissions of significant concentrations of polycyclic aromatic hydrocarbons (PAHs) and particulate matter (PM) to the atmosphere. This paper aims to assess the pollutant emissions into the atmosphere in real conditions of asphalt paving through sampling and quantification of PM, Black Carbon (BC) and PAHs in fine particulate fraction and PAHs in gas phase. Concentration intervals of PM1.0, PM2.5, BC1.0 and BC2.5 found during a highway reconstruction in Londrina/PR were respectively 5.6-20.5; 6.3-24.2; 2.0-6.8 and 1.8-6.5 µg m-3. During asphalt surfacing at the same city’s central bus station, the concentration intervals were 15.1-75.1; 19.7-150; 5.1-14.6 and 4.9-16.2 µg m-3 for PM1.0, PM2.5, BC1.0 and BC2.5, respectively. PAHs in the gas and PM fractions were found in both situations with higher concentrations in the gas phase. The results of this work can provide useful information to society in order to improve practices and promote lower environmental impact and health protection.
DOI: 10.6084/m9.figshare.14278868.v1
title: Air pollutants emissions in real conditions of asphalt paving. particulate matter (pm), black carbon (bc) and polycyclic aromatic hydrocarbons (pahs)

description: Intensive use of asphalt generates pollutants into the atmosphere which are harmful to the environment and worrying for occupational health. The application of asphalt products leads to emissions of significant concentrations of polycyclic aromatic hydrocarbons (PAHs) and particulate matter (PM) to the atmosphere. This paper aims to assess the pollutant emissions into the atmosphere in real conditions of asphalt paving through sampling and quantification of PM, Black Carbon (BC) and PAHs in fine particulate fraction and PAHs in gas phase. Concentration intervals of PM1.0, PM2.5, BC1.0 and BC2.5 found during a highway reconstruction in Londrina/PR were respectively 5.6-20.5; 6.3-24.2; 2.0-6.8 and 1.8-6.5 µg m-3. During asphalt surfacing at the same city’s central bus station, the concentration intervals were 15.1-75.1; 19.7-150; 5.1-14.6 and 4.9-16.2 µg m-3 for PM1.0, PM2.5, BC1.0 and BC2.5, respectively. PAHs in the gas and PM fractions were found in both situations with higher concentrations in the gas phase. The results of this work can provide useful information to society in order to improve practices and promote lower environmental impact and health protection.
DOI: 10.6084/m9.figshare.14278872.v1
title: Classifying brazilian banknotes (R$) using smartphone image analysis

description: A new method to identify the authenticity of Brazilian banknotes (R$) is proposed using digital image analysis by a smartphone application, Photometrix®, associated with chemometric tools. Authentic banknotes (n = 4) obtained in local bank and falsified (n = 12) by the author himself by means of three printers (laser-Deskjet®, wax-Color Qube® and inkjet-Deskjet®) were used for the development of the methodology. An experimental planning was performed to evaluate the authenticity of the banknotes determining: the best region (holographic band, tactile region in the lower left and right upper number, effigy microimpressions, lower number left, animal figure, watermark and puzzle); Region of Interest (ROI) (16x16; 32x32 and 64x64 pixels), focal length (8, 12, 15 and 20 cm) and variation of the smartphone (Motorola G5 Plus, Samsung S7 and LG K10). The best regions chosen were effigy microimpressions and round the animal. Promising results were obtained from ROI 16x16 pixels with focal length fixed at 10 cm. Thus, the application presents promising features for analyzing the authenticity of banknotes by digital images making it fast, non-destructive, portable, with low cost, and can be accessed by all society.
DOI: 10.6084/m9.figshare.14278871.v1
title: The use of the thalidomide case in the construction of meaning in higher education chemistry classes

description: Studies conducted in the field of education have, in many cases, highlighted the little insertion of teaching and learning theories in Natural Sciences classes, in Higher Education. We developed this study to analyze how Chemistry professors take ownership of a historical case to explain the concepts they develop in their classes. To do so, we analyzed this record of undergraduate classes, at times when professors related pedagogical link-making to the future field of work of the students, using the “Thalidomide case.” We realized that, by showing the importance of studies involving chirality and related concepts, the students’ attention to the content seems to have increased significantly, which expands the possibilities of construction of meaning. Thus, we argue that the pedagogical link-making can significantly contribute to students’ knowledge.
DOI: 10.6084/m9.figshare.14278872
title: Classifying brazilian banknotes (R$) using smartphone image analysis

description: A new method to identify the authenticity of Brazilian banknotes (R$) is proposed using digital image analysis by a smartphone application, Photometrix®, associated with chemometric tools. Authentic banknotes (n = 4) obtained in local bank and falsified (n = 12) by the author himself by means of three printers (laser-Deskjet®, wax-Color Qube® and inkjet-Deskjet®) were used for the development of the methodology. An experimental planning was performed to evaluate the authenticity of the banknotes determining: the best region (holographic band, tactile region in the lower left and right upper number, effigy microimpressions, lower number left, animal figure, watermark and puzzle); Region of Interest (ROI) (16x16; 32x32 and 64x64 pixels), focal length (8, 12, 15 and 20 cm) and variation of the smartphone (Motorola G5 Plus, Samsung S7 and LG K10). The best regions chosen were effigy microimpressions and round the animal. Promising results were obtained from ROI 16x16 pixels with focal length fixed at 10 cm. Thus, the application presents promising features for analyzing the authenticity of banknotes by digital images making it fast, non-destructive, portable, with low cost, and can be accessed by all society.
DOI: 10.6084/m9.figshare.14278876
title: Enzyme immobilization: concepts and effects on proteolysis

description: In recent years, great advances have been observed in the proteomic area regarding the different approaches adopted as top-down, middle-down and bottom-up. Regarding middle-down and bottom-up approaches, a previous step for protein digestion is necessary for further analysis of the generated peptides. Classical digestion protocols employing proteases are usually carried out in solution, which can lead to a number of disadvantages such as high digestion time, enzymatic autolysis and impossibility to reuse the enzymes. In view of these drawbacks, different approaches have been studied and applied for improving enzymatic efficiency, inhibition of autolysis, reduction of digestion time, and to minimize the number of missed cleavages. In the literature, great efforts have been made in order to achieve maximum efficiency in enzymatic digestion, with emphasis on proteases immobilization. In this review, concepts related to protein digestion, immobilization techniques, as well as the main support used for enzyme immobilization are discussed considering new tools for proteomic analysis.
DOI: 10.6084/m9.figshare.14278877
title: Determination of docetaxel and metabolites in plasma by UPLC-MS/MS: method development and clinical application

description: A highly sensitive ultra-performance liquid chromatography tandem mass spectrometry method for the determination of Docetaxel and metabolites (M1+M3) in human plasma samples was developed and validated. The method employs a liquid-liquid extraction and a reversed phase separation Acquity® C18 column BEH C18 (150 x 2.1 mm, 1.7 µm). Mobile phase was a mixture of formic acid 0.1% (eluent A) and acetonitrile plus 0.1% formic acid (eluent B) in isocratic mode. Total analytical run time was 7 min. The interval of method linearity interval was 50 to 3000 ng mL-1 for docetaxel and 5.0 to 300 ng mL-1, for M1+M3 metabolites. Intra-assay and inter-assay precision was coefficient of variation 2.5-15.7% and 5.9-12.6%, respectively and accuracy was 89.0-114.0%. The method was successfully applied in the measurement of docetaxel plasma levels and area under the curve calculation in 31 cancer patients, demonstrating adequate analytical performance for the clinical application in the therapeutic drug monitoring and pharmacokinetics studies.
DOI: 10.6084/m9.figshare.14278876.v1
title: Enzyme immobilization: concepts and effects on proteolysis

description: In recent years, great advances have been observed in the proteomic area regarding the different approaches adopted as top-down, middle-down and bottom-up. Regarding middle-down and bottom-up approaches, a previous step for protein digestion is necessary for further analysis of the generated peptides. Classical digestion protocols employing proteases are usually carried out in solution, which can lead to a number of disadvantages such as high digestion time, enzymatic autolysis and impossibility to reuse the enzymes. In view of these drawbacks, different approaches have been studied and applied for improving enzymatic efficiency, inhibition of autolysis, reduction of digestion time, and to minimize the number of missed cleavages. In the literature, great efforts have been made in order to achieve maximum efficiency in enzymatic digestion, with emphasis on proteases immobilization. In this review, concepts related to protein digestion, immobilization techniques, as well as the main support used for enzyme immobilization are discussed considering new tools for proteomic analysis.
DOI: 10.6084/m9.figshare.14278877.v1
title: Determination of docetaxel and metabolites in plasma by UPLC-MS/MS: method development and clinical application

description: A highly sensitive ultra-performance liquid chromatography tandem mass spectrometry method for the determination of Docetaxel and metabolites (M1+M3) in human plasma samples was developed and validated. The method employs a liquid-liquid extraction and a reversed phase separation Acquity® C18 column BEH C18 (150 x 2.1 mm, 1.7 µm). Mobile phase was a mixture of formic acid 0.1% (eluent A) and acetonitrile plus 0.1% formic acid (eluent B) in isocratic mode. Total analytical run time was 7 min. The interval of method linearity interval was 50 to 3000 ng mL-1 for docetaxel and 5.0 to 300 ng mL-1, for M1+M3 metabolites. Intra-assay and inter-assay precision was coefficient of variation 2.5-15.7% and 5.9-12.6%, respectively and accuracy was 89.0-114.0%. The method was successfully applied in the measurement of docetaxel plasma levels and area under the curve calculation in 31 cancer patients, demonstrating adequate analytical performance for the clinical application in the therapeutic drug monitoring and pharmacokinetics studies.
DOI: 10.6084/m9.figshare.14278880
title: Optimization of extraction conditions of volatile compounds of roasted beef by solid-phase microextraction

description: Aroma is one of the most important sensory attributes for acceptance by beef consumers. The first step in analysing the volatile compounds associated with this attribute is their extraction from the food matrix, solid-phase microextraction has been widely used for volatile compound determination in meat. This study aimed to test six different solid-phase microextraction (SPME) fibre coating materials for their volatile compounds extraction efficiency for roasted beef and to optimize the extraction conditions using response surface methodology. Gas chromatography coupled with a flame ionization detector (GC-FID) and mass spectrometry (GC-MS) were used. The choice of SPME fibre coating was based in the total area obtained by GC-FID analysis for the six fibre coatings. The optimum time and temperature for SPME extraction was 60 ºC/65 minutes. The mixed-phase fibre coatings showed the best results for extracting volatile compounds in roasted beef as higher number of compounds were identified. The carboxen/polydimethylsiloxane (CAR/PDMS) fibre extracted the largest number of compounds under the optimum extraction condition. Aldehydes were the predominant class of compounds found in roasted beef, followed by alcohols and hydrocarbons.
DOI: 10.6084/m9.figshare.14278886
title: Wastewater-based epidemiology as a strategy for community monitoring, mapping of hotspots and early warning systems o COVID-19

description: The ability to monitor the spread of diseases is essential for prevention, intervention and control practices. In this context, wastewater-based epidemiology (WBE) has been applied to empirically evaluate the exposure of populations to chemical substances and pathogens of emerging concern in near real time. During the current COVID-19 pandemic, WBE remains an innovative epidemiological tool, with the potential to complement infectious disease surveillance systems. Recent studies on WBE and COVID-19 are based on the monitoring of viral RNA fragments as target biomarkers for SARS-CoV-2 via RT-qPCR and allied techniques. Literature results have been shown the potential of WBE as an innovative tool to monitor viral spread in large communities, map contagion curves and hotspots, identify the contribution of asymptomatic individuals, and subsidize early warning systems for disease outbreaks. WBE can offer less expensive responses for monitoring large populations compared to individual clinical tests which are not feasible on large scales. This aspect is important in terms of health surveillance and associated public policies, notably where clinical tests are scarce or underestimated and in less developed regions with inadequate sanitation conditions.
DOI: 10.6084/m9.figshare.14278880.v1
title: Optimization of extraction conditions of volatile compounds of roasted beef by solid-phase microextraction

description: Aroma is one of the most important sensory attributes for acceptance by beef consumers. The first step in analysing the volatile compounds associated with this attribute is their extraction from the food matrix, solid-phase microextraction has been widely used for volatile compound determination in meat. This study aimed to test six different solid-phase microextraction (SPME) fibre coating materials for their volatile compounds extraction efficiency for roasted beef and to optimize the extraction conditions using response surface methodology. Gas chromatography coupled with a flame ionization detector (GC-FID) and mass spectrometry (GC-MS) were used. The choice of SPME fibre coating was based in the total area obtained by GC-FID analysis for the six fibre coatings. The optimum time and temperature for SPME extraction was 60 ºC/65 minutes. The mixed-phase fibre coatings showed the best results for extracting volatile compounds in roasted beef as higher number of compounds were identified. The carboxen/polydimethylsiloxane (CAR/PDMS) fibre extracted the largest number of compounds under the optimum extraction condition. Aldehydes were the predominant class of compounds found in roasted beef, followed by alcohols and hydrocarbons.
DOI: 10.6084/m9.figshare.14278882
title: Kinetic parameters study for the slow pyrolysis of coffee residues based on thermogravimetric analysis

description: Thermal decomposition of coffee husks was investigated by thermogravimetric analyses. The proximate, ultimate and composition analyses were performed. Thermogravimetric tests were realized, the material was heated to 1173 K using five heating rates: 5, 10, 15, 20, 25 K min-1. The kinetic parameters were estimated using the methods of Kissinger-Akahira-Sunose and Friedman, the distributed activation energy model and the independent parallel reactions model. The isoconversional models of Kissinger-Akahira-Sunose and Friedman showed the dependence between determined values of activation energy and mass conversion, the activation energy values varied from 1437.39 to 199.22 kJ mol-1 for Kissinger-Akahira-Sunose and from 127.81 to 230.35 kJ mol-1 for Friedman model. The values of activation energy were determined for Miura-Maki method; varying from 137.39 to 199.22 kJ mol-1. The model of parallel and independent reactions showed the presence of six different reactions (with activation energy values varying from 42.0 to 214.2 kJ mol-1) occurring during coffee husks pyrolysis, indicating a complex reaction. Currently, works regarding the determination of kinetic parameters for coffee husks pyrolysis are not common. The present work is the first report using the model of parallel and independent reactions to estimate kinetic parameters for pyrolysis of coffee husks, a residue widely generated worldwide.
DOI: 10.6084/m9.figshare.14278882.v1
title: Kinetic parameters study for the slow pyrolysis of coffee residues based on thermogravimetric analysis

description: Thermal decomposition of coffee husks was investigated by thermogravimetric analyses. The proximate, ultimate and composition analyses were performed. Thermogravimetric tests were realized, the material was heated to 1173 K using five heating rates: 5, 10, 15, 20, 25 K min-1. The kinetic parameters were estimated using the methods of Kissinger-Akahira-Sunose and Friedman, the distributed activation energy model and the independent parallel reactions model. The isoconversional models of Kissinger-Akahira-Sunose and Friedman showed the dependence between determined values of activation energy and mass conversion, the activation energy values varied from 1437.39 to 199.22 kJ mol-1 for Kissinger-Akahira-Sunose and from 127.81 to 230.35 kJ mol-1 for Friedman model. The values of activation energy were determined for Miura-Maki method; varying from 137.39 to 199.22 kJ mol-1. The model of parallel and independent reactions showed the presence of six different reactions (with activation energy values varying from 42.0 to 214.2 kJ mol-1) occurring during coffee husks pyrolysis, indicating a complex reaction. Currently, works regarding the determination of kinetic parameters for coffee husks pyrolysis are not common. The present work is the first report using the model of parallel and independent reactions to estimate kinetic parameters for pyrolysis of coffee husks, a residue widely generated worldwide.