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1.
Article in Portuguese | LILACS-Express | LILACS | ID: biblio-1574561

ABSTRACT

A presente pesquisa teve como objetivo analisar a relação entre emoções e fraudes ao consumidor, tendo como base o Modelo de Probabilidade de Elaboração (ELM). Para isso, foi realizada análise de sentimentos, por meio do método de Processamento de Linguagem Natural (PLN), com dados do Twitter obtidos no dia do evento, e análise de conteúdo para compreender os fatores que englobam o evento e se empresas com reclamações nos relatórios do PROCON/SP e do site Reclame Aqui estavam relacionadas. Os dados evidenciam que a maioria dos sentimentos provenientes da Black Friday Brasil são negativos e estão relacionados à fraude ao consumidor. Também revelam que indivíduos que apresentaram baixo envolvimento com mensagens persuasivas, utilizaram as emoções como simples indicações, diferente de indivíduos que apresentaram alto envolvimento e que utilizaram as emoções como argumento no processo persuasivo para não serem vítimas de fraude.


La presente investigación tuvo como objetivo analizar la relación entre las emociones y el fraude al consumidor, basado en el modelo de probabilidad de elaboración (ELM). Para eso, se realizó un análisis de sentimiento, utilizando el método de procesamiento del lenguaje natural (PLN), con datos de Twitter obtenidos el día del evento, y análisis de contenido para comprender los factores que componen el evento y si empresas con quejas en los informes PROCON/SP y el sitio web de Reclame Aquí estaban relacionados. Los datos muestran que la mayoría de los sentimientos del Black Friday Brasil son negativos y están relacionados con el fraude al consumidor. También revelan que las personas que tenían poca implicación con mensajes persuasivos utilizaron las emociones como simples indicaciones, a diferencia de las personas que tenían una alta implicación y que utilizaron las emociones como argumento en el proceso persuasivo para no ser víctimas de fraude.


This research aimed at analyzing the relation between emotions and consumer fraud, based on the Elaboration Likelihood Model (ELM). For this purpose, Sentiment Analysis was performed using the Natural Language Processing (NLP) from Twitter data obtained on the day of the event, and content analysis to understand the factors involved in the event and whether companies with reported complaints on PROCON/SP (2019) and the website Reclame Aqui (2019) were related. The results show that most emotions arising from Black Friday Brazil are both negative and related to consumer fraud. They also reveal that individuals who had low involvement with the persuasive messages used emotions as simple indications, unlike individuals who were highly involved and used emotions as an argument in the persuasive process to avoid being victims of fraud.

2.
Biol Trace Elem Res ; 199(10): 3939-3949, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33188459

ABSTRACT

An acid digestion procedure of the forage palm (Opuntia ficus-indica Mill and Nopalea cochenilifera) employing a closed digestor block applied full 24 factorial design was optimized. The optimal conditions were HNO3 5.0 mol L-1, 2.0 mL of H2O2 30% m m-1, 120 min of digestion, and heating temperature of 180 °C. The certified reference materials of apple leaves (NIST 1515) and tomato leaves (Agro C1003a) were used to evaluate the accuracy of the analytical method. The concentrations of the macroelements were (in % m m-1) Ca (1.32-3.71), K (0.88-5.29), Mg (0.70-1.78), and P (0.03-0.32). For the microelements, the concentrations (in µg g-1) obtained were As (< 1.39), Cd (< 0.10), Cu (< 0.17-5.6), Fe (8.0-50.2), Na (< 1.85), Sr (41-348), and Zn (17.3-159). Essential elements such as Ca, Mg, and Zn made good contributions to daily intake, being an alternative to meet the nutritional needs of these macroelements and microelements in humans. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to evaluate the results, obtaining trends between the samples in relation to their mineral composition.


Subject(s)
Opuntia , Humans , Hydrogen Peroxide , Ions , Minerals
3.
Heliyon ; 6(10): e05163, 2020 Oct.
Article in English | MEDLINE | ID: mdl-33088946

ABSTRACT

Polycyclic aromatic hydrocarbons (PAHs) are part of a class of organic compounds resistant to natural degradation. In this way, heterogeneous photocatalysis becomes useful to degrade persistent organic pollutants, however it can be influenced by environmental variables (i.e.: organic matter) and experimental factors such as: mass of the photocatalyst and irradiation time. The objective of this research was to use a factorial design 2k as a function of the multiple response (MR) to evaluate simultaneously experimental conditions for the photodegradation of polycyclic aromatic hydrocarbons in contaminated mangrove sediment and its application in oil from Potiguar Basin in Brazil. The sediment samples collected in Belmonte city (Southern Bahia state) were contaminated with 0.25 mg kg-1 of Acenaphthene, Anthracene, Benzo[a]Anthracene, Indene[1,2,3cd]pyrene, Dibenzo[ah]anthracene, Benzo[ghi]pyrene. Factors such as mass of the photocatalyst and irradiation time were evaluated in factorial design 22, with triplicate from the central point, to 1g of the PAH contaminated sediment. After performing the experiments, it was found that the best experimental condition for the degradation of all PAHs indicated by MR was the central point (0.5 g of photocatalyst and 12h of irradiation). For such conditions, the half-life of PAHs varied from 3.51 to 9.37 h and the degradation speed constant between 0.0740 to 0.1973 h-1. The comparison of the optimized methodology between photolysis tests and heterogeneous photocatalysis was performed using the Kruskal-Wallis test, which indicated a difference for the reference solution, where heterogeneous photocatalysis was more efficient in the degradation of PAHs. The optimized methodology was apply in samples contaminated with crude oil from Potiguar Basin, no significant difference was observed in the aromatic fraction, using for the Kruskal-Wallis test. Heterogeneous photocatalysis has shown to be a promising remediation technique to remedy aromatic organic compounds in mangrove sediments.

4.
Mar Pollut Bull ; 160: 111597, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32896715

ABSTRACT

The characterization of petroleum or its products spilled in the environment in relation to its source rocks is an important tool to assist in the resolution of issues of environmental impact and legal responsibility since it clarifies the possible region or the producing country of that type of petroleum. This article analyzes the application of analytical techniques for petroleum geochemistry to identify the type and origin of oily material collected from beaches in Northeast Brazil in 2019. Samples of the oily material collected on the beaches in the states of Bahia and Sergipe were analyzed and for comparison purposes, samples of crude oils produced in Brazil, Middle East, Nigeria and Venezuela were also analyzed. The analytical results showed that the oily material that reached the beaches has geochemical characteristics compatible with those of the Venezuelan oil, indicating it was severely weathered or a product made with heavy oil produced.


Subject(s)
Disasters , Petroleum Pollution , Petroleum , Water Pollutants, Chemical , Brazil , Environmental Monitoring , Middle East , Nigeria , Petroleum/analysis , Petroleum Pollution/analysis , Venezuela , Water Pollutants, Chemical/analysis
5.
Environ Geochem Health ; 42(7): 2179-2193, 2020 Jul.
Article in English | MEDLINE | ID: mdl-31853769

ABSTRACT

In this work, a methodology for chemical speciation analysis of inorganic As and Sb in urban dust using slurry sampling and detection by fast sequential hydride generation atomic absorption spectrometry is proposed. Doehlert design and desirability function were used to find the optimum conditions for hydride generation (1.0 mol L-1 HCl and 0.9% m v-1 NaBH4). The accuracy of the analytical method was evaluated by analysis of reference material fly ash (BCR 176R), addition and recovery tests for inorganic As species, and comparison of independent methods for Sb determination in urban dust samples. The determination of the total concentrations of As and Sb and their inorganic species presented good accuracy, between 80 ± 1 and 101 ± 6%. Precision was expressed as the relative standard deviation and was better than 4.7% (n = 3). The limit-of-quantification values were 0.23 and 1.03 mg kg-1 for As and Sb, respectively. The methodology was applied to eight samples of dust collected in an urban area of Salvador and Jaguaquara cities, Bahia, Northeast, Brazil, with an aerodynamic size lower than 38 µm. Concentrations of pentavalent inorganic species (iAs5+ and iSb5+) in relation to trivalent species (iAs3+ and iSb3+) were found in urban dust collected in the city of Salvador, which are regarded as more toxic for both elements. The enrichment factor and geoaccumulation index (Igeo) values showed that for some samples, the concentrations of iAs and iSb presented strong enrichment and, and regarding environment, strong to moderately polluted by iAs and iSb, with an indication of anthropogenic contributions. The occurrence of these inorganic constituents in the urban area of Salvador can be related with intense industrial activities and vehicular traffic.


Subject(s)
Air Pollutants/analysis , Antimony/analysis , Arsenic/analysis , Dust/analysis , Environmental Monitoring/methods , Air Pollutants/chemistry , Antimony/chemistry , Arsenic/chemistry , Brazil , Cities , Limit of Detection , Spectrophotometry, Atomic
6.
Food Chem ; 273: 106-114, 2019 Feb 01.
Article in English | MEDLINE | ID: mdl-30292355

ABSTRACT

This work describes the application of an experimental design in optimizing the decomposition and spectrometer operational conditions for analysis of fish feeds. The content of 22 elements (six macroelements, four microelements and eleven trace elements) in feeds for fishes (ornamental and for human consumption) was determined by inductively coupled plasma (ICP)-based methods. Limits of quantification were obtained and the values ranged between 0.02 mg kg-1 (Cd) and 76 mg kg-1 (Al). Evaluation of the methods was achieved through analysis of standard reference material, Oyster Tissue (NIST 1566b) and Tea (NCS DC 73351). Element concentrations in feed samples for ornamental fish ranged from <0.02 mg kg-1 (Cd) to 2.79% (P) and for fish breeding for human consumption from <0.02 mg kg-1 (Cd) to 2.00% (Ca). The concentrations of the elements obtained in the analyzed fish feeds were within the limits established by Brazilian and American legislation for regulated elements.


Subject(s)
Animal Feed/analysis , Fishes , Mass Spectrometry/methods , Minerals/analysis , Animals , Aquaculture , Brazil , Humans , Limit of Detection , Phosphorus/analysis , Trace Elements/analysis
7.
J AOAC Int ; 101(3): 876-882, 2018 May 01.
Article in English | MEDLINE | ID: mdl-28911344

ABSTRACT

Three spectrophotometric methods were developed for the determination of copper (Cu) in sugar cane spirit using the chromogenic reagents neocuproine, cuprizone, and bathocuproine. Experimental conditions, such as reagent concentration, reducer concentration, pH, buffer concentration, the order of addition of reagents, and the stability of the complexes, were optimized. The work range was established from 1.0 to 10.0 µg/mL, with correlation coefficients of >0.999 for all three optimized methods. The methods were evaluated regarding accuracy by addition and recovery tests at five concentration levels, and the obtained recoveries ranged from 91 to 105% (n = 3). Precision was expressed as RSD (relative standard deviation), with values ranging from 0.01 to 0.17% (n = 10). The method using the chromogenic reagent cuprizone presented the greatest molar absorptivity, followed by bathocuproine and neocuproine. The methods were applied for the determination of Cu in sugar cane spirit, and the results were compared with a reference method by flame atomic absorption spectrometry (FAAS). Calibration curve solutions for FAAS analysis were prepared in a 40% (v/v) alcohol medium in a range of concentrations from 0.5 up to 5 µg/mL. Measurements for Cu determination were carried out at a wavelength of 324.7 nm. The concentrations obtained for Cu in sugar cane spirit samples from Brazil were between 1.99 and 12.63 µg/mL, and about 75% of the samples presented Cu concentrations above the limit established by Brazilian legislation (5.0 µg/mL or 5.0 mg/L).


Subject(s)
Copper/analysis , Spectrophotometry/methods , Brazil , Calibration , Chelating Agents/chemistry , Coordination Complexes/chemistry , Copper/chemistry , Cuprizone/chemistry , Hydrogen-Ion Concentration , Hydroxylamine , Indicators and Reagents/chemistry , Ligands , Limit of Detection , Oxidation-Reduction , Phenanthrolines/chemistry , Saccharum
8.
Talanta ; 178: 842-846, 2018 Feb 01.
Article in English | MEDLINE | ID: mdl-29136903

ABSTRACT

This work presents the optimization of a sample preparation procedure using microwave-assisted digestion for the determination of nickel and vanadium in crude oil employing inductively coupled plasma optical emission spectrometry (ICP OES). The optimization step was performed utilizing a two-level full factorial design involving the following factors: concentrated nitric acid and hydrogen peroxide volumes, and microwave-assisted digestion temperature. Nickel and vanadium concentrations were used as responses. Additionally, a multiple response based on the normalization of the concentrations by the highest values was built to establish a compromise condition between the two analytes. A Doehlert matrix optimized the instrumental conditions of the ICP OE spectrometer. In this design, the plasma robustness was used as chemometric response. The experiments were performed using a digested oil sample solution doped with magnesium(II) ions, as well as a standard magnesium solution. The optimized method allows for the determination of nickel and vanadium with quantification limits of 0.79 and 0.20µgg-1, respectively, for a digested sample mass of 0.1g. The precision (expressed as relative standard deviations) was determined using five replicates of two oil samples and the results obtained were 1.63% and 3.67% for nickel and 0.42% and 4.64% for vanadium. Bismuth and yttrium were also tested as internal standards, and the results demonstrate that yttrium allows for a better precision for the method. The accuracy was confirmed by the analysis of the certified reference material trace element in fuel oil (CRM NIST 1634c). The proposed method was applied for the determination of nickel and vanadium in five crude oil samples from Brazilian Basins. The metal concentrations found varied from 7.30 to 33.21µgg-1 for nickel and from 0.63 to 19.42µgg-1 for vanadium.

9.
Biochem Pharmacol ; 77(1): 66-75, 2009 Jan 01.
Article in English | MEDLINE | ID: mdl-18851956

ABSTRACT

This study investigated the effects of atorvastatin on ABCB1 and ABCC1 mRNA expression on peripheral blood mononuclear cells (PBMC) and their relationship with gene polymorphisms and lowering-cholesterol response. One hundred and thirty-six individuals with hypercholesterolemia were selected and treated with atorvastatin (10 mg/day/4 weeks). Blood samples were collected for serum lipids and apolipoproteins measurements and DNA and RNA extraction. ABCB1 (C3435T and G2677T/A) and ABCC1 (G2012T) gene polymorphisms were identified by polymerase chain reaction-restriction (PCR)-RFLP and mRNA expression was measured in peripheral blood mononuclear cells by singleplex real-time PCR. ABCB1 polymorphisms were associated with risk for coronary artery disease (CAD) (p<0.05). After atorvastatin treatment, both ABCB1 and ABCC1 genes showed 50% reduction of the mRNA expression (p<0.05). Reduction of ABCB1 expression was associated with ABCB1 G2677T/A polymorphism (p=0.039). Basal ABCB1 mRNA in the lower quartile (<0.024) was associated with lower reduction rate of serum low-density lipoprotein (LDL) cholesterol (33.4+/-12.4%) and apolipoprotein B (apoB) (17.0+/-31.3%) when compared with the higher quartile (>0.085: LDL-c=40.3+/-14.3%; apoB=32.5+/-10.7%; p<0.05). ABCB1 substrates or inhibitors did not affect the baseline expression, while ABCB1 inhibitors reversed the effects of atorvastatin on both ABCB1 and ABCC1 transporters. In conclusion, ABCB1 and ABCC1 mRNA levels in PBMC are modulated by atorvastatin and ABCB1 G2677T/A polymorphism and ABCB1 baseline expression is related to differences in serum LDL cholesterol and apoB in response to atorvastatin.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/biosynthesis , ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics , Gene Expression Regulation/genetics , Heptanoic Acids/pharmacology , Leukocytes, Mononuclear/metabolism , Multidrug Resistance-Associated Proteins/biosynthesis , Multidrug Resistance-Associated Proteins/genetics , Polymorphism, Genetic/genetics , Pyrroles/pharmacology , ATP Binding Cassette Transporter, Subfamily B , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Aged , Anticholesteremic Agents/pharmacology , Atorvastatin , Female , Gene Expression Regulation/drug effects , Humans , Leukocytes, Mononuclear/drug effects , Male , Middle Aged , Multidrug Resistance-Associated Proteins/metabolism , Polymorphism, Genetic/drug effects
10.
Biochemical Pharmacology ; 77: 66-75, 2009.
Article in English | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1060819

ABSTRACT

This study investigated the effects of atorvastatin on ABCB1 and ABCC1 mRNA expression on peripheral blood mononuclear cells (PBMC) and their relationship with gene polymorphismsand lowering-cholesterol response. One hundred and thirty-six individuals withhypercholesterolemia were selected and treated with atorvastatin (10 mg/day/4 weeks). Blood samples were collected for serum lipids and apolipoproteins measurements and DNA and RNA extraction. ABCB1 (C3435T and G2677T/A) and ABCC1 (G2012T) gene polymorphisms were identified by polymerase chain reaction-restriction (PCR)-RFLP and mRNA expression was measured in peripheral blood mononuclear cells by singleplex real-time PCR. ABCB1 polymorphisms were associated with risk for coronary artery disease (CAD) ( p 0.085: LDL-c = 40.3 14.3%; apoB = 32.5 10.7%; p < 0.05). ABCB1 substrates or inhibitors did not affect the baseline expression, while ABCB1 inhibitors reversedthe effects of atorvastatin on both ABCB1 and ABCC1 transporters. In conclusion, ABCB1 and ABCC1 mRNA levels in PBMC are modulated by atorvastatin and ABCB1 G2677T/A polymorphism and ABCB1 baseline expression is related to differences in serum LDL cholesterol and apoB in response to atorvastatin.


Subject(s)
Gene Expression , Pharmacogenetics , Polymorphism, Genetic
11.
Clin Chim Acta ; 389(1-2): 79-86, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18164264

ABSTRACT

BACKGROUND: ABCA1 plays an important role in HDL metabolism. Single nucleotide polymorphisms (SNPs) in ABCA1 gene were associated with variation in plasma HDL-c. METHODS: The effect of the ABCA1 SNPs C-14T, R219K and of a novel variant C-105T on serum lipids was investigated in 367 unrelated Brazilian individuals (224 hypercholesterolemic and 143 normolipidemic). The relation between ABCA1 SNPs and the lipid-lowering response to atorvastatin (10 mg/day/4 weeks) was also evaluated in 141 hypercholesterolemic (HC) individuals. The polymorphisms were detected by PCR-RFLP and confirmed by DNA sequencing. RESULTS: Linkage disequilibrium was found between the SNPs C-105T and C-14T in the HC group. HC individuals carrying -105CT/TT genotypes had higher serum HDL-c and lower triglyceride and VLDL-c concentrations as well as lower TG/HDL-c ratio compared to the -105CC carriers (p<0.05). The R219K SNP was associated with reduced serum triglyceride, VLDL-c and TG/HDL-c ratio in the HC group (p<0.05), and with an increased serum apoAI in NL individuals. The effects of ABCA1 SNPs on basal serum lipids of HC individuals were not modified by atorvastatin treatment. CONCLUSIONS: The ABCA1 SNPs R219K and C-105T were associated with a less atherogenic lipid profile but not with the lowering-cholesterol response to atorvastatin in a Brazilian population.


Subject(s)
ATP-Binding Cassette Transporters/genetics , Lipids/blood , Polymorphism, Single Nucleotide , ATP Binding Cassette Transporter 1 , Adult , Base Sequence , Brazil , DNA Primers , Female , Humans , Linkage Disequilibrium , Male , Middle Aged
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