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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 310: 123965, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38295596

RESUMO

The simulated distillation curve (ASTM/D-7169) is a quantitative method to determine fractions of crude oils by boiling point temperature ranges (36-720 °C). In this work, 45 samples of typical Colombian crudes were selected, and the samples were produced under conventional process. Also 8 upgraded crude oils under catalytic aquathermolysis conditions at laboratory scale were added. The tests were developed at 270 °C and 800psi (@25 °C) during 66 h of reaction. In addition, 30 samples were selected for density tests, according to the pycnometer method. Subsequently, the crude oil samples under study were diluted in chloroform and analyzed by UV-VIS Spectroscopy. The UV-VIS spectra were correlated with selected properties by using PCA-MLR and PLS models. The distillation curves of the crude oils were modelled using the Riazi probability function. The prediction models of parameters To, A, and B from the Riazi probability function exhibited R2 correlation coefficients, higher than 0.94. The correlation model for the crude oil density showed a much better coefficient, higher than 0.99 and Root-Mean-Squared-Error (RMSE) close to 0.004. Additionally, even more important is the contribution of the use of UV-VIS spectroscopy as a useful tool to quickly evaluate the quality of crude oil.

2.
J Anim Sci ; 1012023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37681983

RESUMO

The objective of the present study was to verify the effect of handling in corrals on the stress of beef cattle of Nelore, Caracu, and Guzerá breeds through the analysis of the relationship between behavioral traits, growth, and blood parameters. A total of 778 records of entry scores, chute scores, exit scores, flight speed, cortisol, glucose, lactate, live weight, and body condition scores were collected on steers and heifers of the three breeds, born between September and December. The animals came from the Advanced Beef Cattle Research Center of the Animal Science Institute. The variance analyses were performed using the GENMOD procedure. The PROC CORR estimated Spearman correlation coefficients for all traits studied, and the principal components analysis was performed according to the procedure PRINCOMP. Heifers had higher reactivity than steers, with higher behavioral scores and blood parameters. Overall, Caracu individuals demonstrated lower reactivity in comparison to Nelore and Guzerá. However, they presented high stress when they were restrained. The principal component analysis highlighted that behavioral traits and blood parameters were contrasted with growth traits; thus, this analysis can help selectors (livestock farmers) understand the importance of selecting less reactive animals and more easily choose the animals they want to select for breeding. Our results indicate that handling in corrals could be considered a stressful event for bovines. For this reason, measuring blood parameters and behavioral traits can compose necessary decision-making tools regarding changes and adequacies while handling events to reduce stress and consequently improve the herd's reactivity.


Some scientific studies have shown the negative effect of poor handling on the welfare and temperament of animals. Furthermore, there is evidence that more reactive cattle present the highest blood cortisol concentrations indicative of stress. In our study, the objective was to evaluate and quantify the temperament of animals from three different breeds of beef cattle in a stressful situation handled in the corrals. Differences in behavior between breeds and sexes were also analyzed. Through a statistical method, such as principal component analysis, we verified that exit and chute scores are better behavioral indicators of animal stress, allowing the development of sound management practices, especially when passing through the corrals.


Assuntos
Parto , Temperamento , Humanos , Gravidez , Bovinos , Animais , Feminino , Brasil , Cruzamento , Ácido Láctico
3.
J Nutr Sci ; 12: e80, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37528831

RESUMO

Relatively little is known about how the diet of chronically undernourished children may impact cardiometabolic biomarkers. The objective of this exploratory study was to characterise relationships between dietary patterns and the cardiometabolic profile of 153 3-5-year-old Peruvian children with a high prevalence of chronic undernutrition. We collected monthly dietary recalls from children when they were 9-24 months old. At 3-5 years, additional dietary recalls were collected, and blood pressure, height, weight, subscapular skinfolds and fasting plasma glucose, insulin and lipid profiles were assessed. Nutrient intakes were expressed as average density per 100 kcals (i) from 9 to 24 months and (ii) at follow-up. The treelet transform and sparse reduced rank regress'ion (RRR) were used to summarize nutrient intake data. Linear regression models were then used to compare these factors to cardiometabolic outcomes and anthropometry. Linear regression models adjusting for subscapular skinfold-for-age Z-scores (SSFZ) were then used to test whether observed relationships were mediated by body composition. 26 % of children were stunted at 3-5 years old. Both treelet transform and sparse RRR-derived child dietary factors are related to protein intake and associated with total cholesterol and SSFZ. Associations between dietary factors and insulin were attenuated after adjusting for SSFZ, suggesting that body composition mediated these relationships. Dietary factors in early childhood, influenced by protein intake, are associated with cholesterol profiles, fasting glucose and body fat in a chronically undernourished population.


Assuntos
Doenças Cardiovasculares , Humanos , Criança , Pré-Escolar , Lactente , Peru , Doenças Cardiovasculares/epidemiologia , Ingestão de Alimentos , Colesterol , Biomarcadores , Insulina
4.
Environ Geochem Health ; 45(8): 6027-6041, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37210681

RESUMO

The assessment of soil quality improvement provided by biochars is complex and rarely examined. In this work, soil quality indices (SQIs) were produced to evaluate coffee industry feedstock biochars improvement on soil quality samples of a heavy metal-multicontaminated soil. Therefore, a 90-day incubation experiment was carried out with the following treatments: contaminated soil (CT), contaminated soil with pH raised to 7.0 (CaCO3), contaminated soil + 5% (m/m) coffee ground biochar, and contaminated soil + 5% (m/m) coffee parchment biochar (PCM). After incubation, chemical and biological attributes were analyzed, and the data were subjected to principal component analysis and Pearson correlation to obtain a minimum dataset (MDS), which explain the majority of the variance of the data. The MDS-selected attributes were dehydrogenase and protease activity, exchangeable Ca content, phytoavailable content of Cu, and organic carbon, which composed the SQI. The resulting SQI ranged from 0.50 to 0.56, with the highest SQI obtained for the PCM treatment and the lowest for the CT. The phytoavailable content Cu was the determining factor for differentiating PCM from the other treatments, which was a biochar original attribute and helped to improve soil quality based on the SQI evaluation, further than heavy metal immobilization due to the soil sample pH increase. Longer-term experiments may illustrate clearer advantages of using biochar to improve heavy metal-contaminated soil quality, as physical attributes may also respond, and more significant contributions to biological attributes could be obtained as biochar ages.


Assuntos
Metais Pesados , Poluentes do Solo , Solo/química , Melhoria de Qualidade , Poluentes do Solo/análise , Metais Pesados/análise , Carvão Vegetal/química
5.
Artigo em Inglês | MEDLINE | ID: mdl-36767439

RESUMO

BACKGROUND: Excess adiposity is one of the main risk factors for the development of cardiovascular and metabolic diseases. The purpose of this study is to compare cardiometabolic risk factors in eutrophic adolescents with a high body fat percentage (%BF) with eutrophic adolescents with adequate %BF and those with excess weight and %BF. METHODS: Cross-sectional study with 1043 adolescents. This study presented power equal to 99.75%. Body fat and anthropometric, clinical and biochemical indicators were evaluated. Participants were grouped according to body composition classified by body mass index (BMI) and body fat percentage. Statistical analyses were performed using R software version 4.0.2, adopting a significance level of 5%. The Mann-Whitney test, principal components analysis and logistic regression were performed. RESULTS: It was observed that the SG was more similar to GC2 than to GC1 for both sexes, demonstrating that there was a greater similarity between these groups in relation to the evaluated factors. Higher values for TC, SBP and TG were associated with the SG when the CG1 was used as reference, controlled for sex and age. Likewise, higher TC values and lower levels of SBP, TG and LDL were related to SG when the CG2 was used as reference. CONCLUSION: Body fat assessment is more effective in predicting risk factors and cardiometabolic diseases than BMI alone.


Assuntos
Fatores de Risco Cardiometabólico , Doenças Cardiovasculares , Masculino , Feminino , Humanos , Adolescente , Índice de Massa Corporal , Estudos Transversais , Absorciometria de Fóton , Tecido Adiposo , Fatores de Risco , Adiposidade , Composição Corporal , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia
6.
Microsc Microanal ; : 1-9, 2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35431023

RESUMO

Analytical studies of nanoparticles (NPs) are frequently based on huge datasets derived from hyperspectral images acquired using scanning transmission electron microscopy. These large datasets require machine learning computational tools to reduce dimensionality and extract relevant information. Principal component analysis (PCA) is a commonly used procedure to reconstruct information and generate a denoised dataset; however, several open questions remain regarding the accuracy and precision of reconstructions. Here, we use experiments and simulations to test the effect of PCA processing on data obtained from AuAg alloy NPs a few nanometers wide with different compositions. This study aims to address the reliability of chemical quantification after PCA processing. Our results show that the PCA treatment mitigates the contribution of Poisson noise and leads to better quantification, indicating that denoised results may be reliable from the point of view of both uncertainty and accuracy for properly planned experiments. However, the initial data need to be of sufficient quality: these results can only be obtained if the signal-to-noise ratio of input data exceeds a minimal value to avoid the occurrence of random noise bias in the PCA reconstructions.

7.
PeerJ ; 10: e13123, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35317074

RESUMO

Background: The geometric morphometric analysis is applied for the first time for the family Tipulidae to distinguish evolutionary and biogeographical patterns on Ischnotoma species from Neotropical and Australian regions. We included 45 recognized species of the genus, representing its three subgenera I. (Icriomastax), I. (Ischnotoma), and I. (Neotipula). This paper aims to test if the three subgenera are recoverable using this set of morphometric data. Methods: Twenty-two landmarks were selected on the wing, mostly located on the radial and medial veins. A Regression Analysis, Principal Components Analysis (PCA), a Shape Coordinates PCA and a Canonical Variate Analysis (CVA) were used to test the variations among individuals, wing shape and groups. Results: For all analyses, the species of Ischnotoma (Neotipula) has a strong dissociation from the remaining species and the CVA shows a complete separation of the three subgenera. This study represents the first insight for a new assessment of Ischnotoma and the first step to giving a possible new status for I. (Neotipula).


Assuntos
Dípteros , Animais , Austrália , Evolução Biológica , Nematóceros , Asas de Animais
8.
Bol. malariol. salud ambient ; 62(3): 383-396, 2022. tab, graf
Artigo em Espanhol | LILACS, LIVECS | ID: biblio-1395368

RESUMO

En la investigación se determinaron la presencia de geohelmintos y se evaluó la calidad ambiental del suelo mediante parámetros fisicoquímicos en el distrito de José Crespo y Castillo ­ Huánuco, Perú. Se detectaron y cuantificaron los geohelmintos, se caracterizó los perfiles modales y propiedades fisicoquímicas en función del Soil Taxonomy, y contraste con el estándar de calidad para el cadmio (Cd) y determinación del índice de calidad ambiental del suelo empleando el análisis de componentes principales. Los perfiles modales son Fluventic Eutrudepts, Lithic Udorthents, Typic Dystrudepts, Typic Dystrudepts - Lithic Udorthents, Typic Dystrudepts - Typic Endoaquents, Typic Endoaquents, Typic Eutrudepts - Typic Eutrudepts, Typic Udifluvents y Typic Udorthents; los parámetros fisicoquímicos textura, pH, materia orgánica, nitrógeno, fosforo disponible, potasio disponible, cadmio disponible, capacidad de intercambio catiónico efectivo, calcio, magnesio, aluminio, hidrogeno, bases y ácidos cambiables y porcentaje de saturación de aluminio, determinando que el cadmio disponible se encuentra dentro de los estándares de calidad ambiental del Perú; y el índice de calidad ambiental del suelo es de 41,48%, teniendo la calificación de un suelo regular de calidad ambiental. Y la contaminación por Ascaris lumbricoides fue en 25 de las calicatas (55,56%), presente en los 8 tipos de suelos catalogados, seguida de las unicinarias representadas por Necator americano y Ancylostoma duodenale en 14 calicatas (31,11%) de pH ligeramente a medianamente acido, y Taenias y Capilaria, ambos en el 8,29%; los geohelmintos como riesgo de salud pública, permanecen por largo de tiempo en el suelo, independientemente de la calidad y en amplios rangos de pH, favorecidos por niveles de sustratos orgánicos derivados de la antropogénesis(AU)


In the investigation, the presence of geohelminths was determined and the environmental quality of the soil was evaluated through physicochemical parameters in the district of José Crespo y Castillo - Huánuco, Peru. Geohelminths were detected and quantified and the modal profiles and physicochemical properties were characterized based on the Soil Taxonomy, and contrast with the quality standard for cadmium (Cd) and determination of the environmental quality index of the soil using the main component analysis. Modal profiles are Fluventic Eutrudepts, Lithic Udorthents, Typic Dystrudepts, Typic Dystrudepts - Lithic Udorthents, Typic Dystrudepts - Typic Endoaquents, Typic Endoaquents, Typic Eutrudepts - Typic Eutrudepts, Typic Udifluvents, and Typic Udorthents; the physicochemical parameters texture, pH, organic matter, nitrogen, available phosphorus, available potassium, available cadmium, effective cation exchange capacity, calcium, magnesium, aluminium, hydrogen, exchangeable bases and acids and percentage of aluminum saturation, determining that cadmium available is within the environmental quality standards of Peru; and the environmental quality index of the soil is 41.48%, having the qualification of a regular soil of environmental quality. And the contamination by Ascaris lumbricoides was in 25 of the pits (55.56%), present in the 8 types of cataloged soils, followed by the unicinarias represented by Necator americano and Ancylostoma duodenale in 14 pits (31.11%) of pH slightly to medium acid, and Taenias and Capilaria, both at 8.29%; As a public health risk, geohelminths remain in the soil for a long time, regardless of quality and in wide pH ranges, favored by levels of organic substrates derived from anthropogenesis(AU)


Assuntos
Zonas Agrícolas , Qualidade Ambiental , Poluição Ambiental , Indicadores e Reagentes , Padrões de Referência , Cádmio , Concentração de Íons de Hidrogênio
9.
Vet Sci ; 8(12)2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34941856

RESUMO

Mastitis is a disease that causes significant economic losses, since resistance to mastitis is a difficult trait to be improved due to its multifactorial occurrence. Therefore, our objective was to characterize a Mexican Braunvieh cattle population for genetic resistance and susceptibility to mastitis. We used 66 SNP markers for 45 candidate genes in 150 animals. The average heterozygosity was 0.445 ± 0.076, a value higher than those reported for some European breeds. The inbreeding coefficient was slightly negative for resistance to subclinical (-0.058 ± 0.055) and clinical (-0.034 ± 0.076) mastitis, possibly due to low selection for the immunological candidate genes that influence these traits. The genotypic profiles for the candidate loci per K-means group were obtained, as well as the group distribution through the graphics of the principal component analysis. The genotypic profiles showed high genetic diversity among groups. Resistance to clinical mastitis had the lowest presence of the heterozygous genotypes. Although the percentage of highly inbred animals (>50%) is up to 13.3%, there are highly heterozygous groups in terms of the studied traits, a favorable indicator of the presence of genetic diversity. The results of this study constitute evidence of the genetic potential of the Mexican Braunvieh population to improve mastitis-related traits.

10.
Ciênc. rural (Online) ; 51(3): e20200629, 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1153861

RESUMO

ABSTRACT: The present research presents an analytical methodology based on High Performance Liquid Chromatography (HPLC) and Principal Component Analyses (PCA) for simultaneous quantification and analytical differentiation of organic acids and sugars in commercial fruit juice samples (orange, grape, apple and tangerine). In addition to the development of the method that generated suitable validation paramters for quantitative analytical applications, the analysis of fourteen commercial samples and the use of Principal Component Analysis indicated the relationship between the constituents and the very constitutional chemical nature of the juice. In general, in grape and apple juices, ascorbic acid was not quantified and the citric acid content was very low; however, the concentrations of fructose and glucose were the highest in both juices. In orange and mandarin orange juices, the content of all analytes, except acorbic acid, did not differ statistically from each other. However, these differed significantly from the others, mainly in relation to sucrose content. Finally, the apple juice samples differed according to the content of fructose and malic acid, the predominant constituint of the apple. Results showed that the simultaneous chromatographic method associated with principal component analysis generated important information about characteristics of commercial juices, with the potential to be used in systems of quality control and identification of adulterations.


RESUMO: O presente trabalho apresenta uma metodologia analítica baseada em Cromatografia Líquida de Alto Desempenho (CLAE) e Análise de Componentes Principais (ACP) para quantificação simultânea e diferenciação analítica de ácidos orgânicos e açúcares em amostras comerciais de suco de frutas (laranja, uva, maçã e tangerina). Além do desenvolvimento do método que gerou parâmetros de validação adequados para aplicações analítica quantitativas, a análise de catorze amostras comerciais e o uso da ACP indicaram a relação entre os analitos e a natureza química constitucional do suco. Em geral, nos sucos de uva e maçã não foi quantificado ácido ascórbico sendo o conteúdo de ácido cítrico muito baixo, no entanto, as concentrações de frutose e glicose foram as mais altas em ambos sucos. Nos sucos de laranja e tangerina, o conteúdo de todos os analitos, exceto o ácido ascórbico, não diferiram estatisticamente entre si. No entanto, diferiram significativamente dos demais, principalmente em relação ao conteúdo de sacarose. Finalmente, as amostras de suco de maçã diferiram de acordo com o teor de frutose e ácido málico, constituinte predominante da maçã. Os resultados mostraram que o método comatográfico simultâneo associado à análise de componentes principais gera informações importantes sobre as características dos sucos comerciais, com potencialidade para ser utilizado em sistemas de controle de qualidade e identificação de adulterações.

11.
Braz. J. Pharm. Sci. (Online) ; 57: e18899, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1339302

RESUMO

Microbiological quality of pharmaceuticals is fundamental in ensuring efficacy and safety of medicines. Conventional methods for microbial identification in non-sterile drugs are widely used; however they can be time-consuming and laborious. The aim of this paper was to develop a chemometric-based rapid microbiological method (RMM) for identifying contaminants in pharmaceutical products using Fourier transform infrared with attenuated total reflectance spectrometry (FTIR-ATR). Principal components analysis (PCA) and linear discriminant analysis (LDA) were used to obtain a predictive model capable of distinguishing Bacillus subtilis (ATCC 6633), Candida albicans (ATCC 10231), Enterococcus faecium (ATCC 8459), Escherichia coli (ATCC 8739), Micrococcus luteus (ATCC 10240), Pseudomonas aeruginosa (ATCC 9027), Salmonella typhimurium (ATCC 14028), Staphylococcus aureus (ATCC 6538), and Staphylococcus epidermidis (ATCC 12228) microbial growth. FTIR-ATR spectra provide data on proteins, DNA/RNA, lipids, and carbohydrates constitution of microbial growth. Microbial identification provided by PCA/LDA based on FTIR-ATR method were compatible with those obtained using traditional microbiological methods. The chemometric-based FTIR-ATR method for rapid identification of microbial contaminants in pharmaceutical products was validated by assessing the sensitivity (93.5%), specificity (83.3%), and limit of detection (17-23 CFU/mL of sample). Therefore, we propose that FTIR-ATR spectroscopy may be used for rapid identification of microbial contaminants in pharmaceutical products and taking into account the samples studied


Assuntos
Análise Espectral/instrumentação , Preparações Farmacêuticas/análise , Análise Discriminante , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise de Fourier , Pseudomonas aeruginosa/classificação , Bacillus subtilis/classificação , Candida albicans/classificação , Limite de Detecção
12.
Ci. Rural ; 51(3)2021. mapas, ilus
Artigo em Inglês | VETINDEX | ID: vti-31130

RESUMO

The present research presents an analytical methodology based on High Performance Liquid Chromatography (HPLC) and Principal Component Analyses (PCA) for simultaneous quantification and analytical differentiation of organic acids and sugars in commercial fruit juice samples (orange, grape, apple and tangerine). In addition to the development of the method that generated suitable validation paramters for quantitative analytical applications, the analysis of fourteen commercial samples and the use of Principal Component Analysis indicated the relationship between the constituents and the very constitutional chemical nature of the juice. In general, in grape and apple juices, ascorbic acid was not quantified and the citric acid content was very low; however, the concentrations of fructose and glucose were the highest in both juices. In orange and mandarin orange juices, the content of all analytes, except acorbic acid, did not differ statistically from each other. However, these differed significantly from the others, mainly in relation to sucrose content. Finally, the apple juice samples differed according to the content of fructose and malic acid, the predominant constituint of the apple. Results showed that the simultaneous chromatographic method associated with principal component analysis generated important information about characteristics of commercial juices, with the potential to be used in systems of quality control and identification of adulterations.(AU)


O presente trabalho apresenta uma metodologia analítica baseada em Cromatografia Líquida de Alto Desempenho (CLAE) e Análise de Componentes Principais (ACP) para quantificação simultânea e diferenciação analítica de ácidos orgânicos e açúcares em amostras comerciais de suco de frutas (laranja, uva, maçã e tangerina). Além do desenvolvimento do método que gerou parâmetros de validação adequados para aplicações analítica quantitativas, a análise de catorze amostras comerciais e o uso da ACP indicaram a relação entre os analitos e a natureza química constitucional do suco. Em geral, nos sucos de uva e maçã não foi quantificado ácido ascórbico sendo o conteúdo de ácido cítrico muito baixo, no entanto, as concentrações de frutose e glicose foram as mais altas em ambos sucos. Nos sucos de laranja e tangerina, o conteúdo de todos os analitos, exceto o ácido ascórbico, não diferiram estatisticamente entre si. No entanto, diferiram significativamente dos demais, principalmente em relação ao conteúdo de sacarose. Finalmente, as amostras de suco de maçã diferiram de acordo com o teor de frutose e ácido málico, constituinte predominante da maçã. Os resultados mostraram que o método comatográfico simultâneo associado à análise de componentes principais gera informações importantes sobre as características dos sucos comerciais, com potencialidade para ser utilizado em sistemas de controle de qualidade e identificação de adulterações.(AU)


Assuntos
Ácidos Orgânicos/análise , Açúcares/administração & dosagem , Açúcares/análise , Sucos de Frutas e Vegetais/análise , Cromatografia Líquida
13.
Isotopes Environ Health Stud ; 56(5-6): 446-464, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32903064

RESUMO

In the eastern region of central Costa Rica, land use in the sub-basins of the Maravilla-Chiz and Quebrada Honda rivers (47 km2) is dominated by agricultural and livestock production, while groundwater resources constitute the main drinking water supply. This study aimed to (a) evaluate the location of groundwater recharge areas and groundwater flow paths, and (b) provide a characterization of the hydrochemistry and possible anthropic impacts. Groundwater was collected from 20 sites during the dry and rainy seasons and analysed for major ions, water stable isotopes and 222Rn. Approximated recharge areas were estimated through a local altitudinal line based on isotopic compositions in springs. The hydrochemical and isotopic characterization of groundwater showed that the main recharge areas occur in the upper part of the basin, except for springs in the middle part of the basin probably due to a certain hydraulic disconnection from the upper part that facilitates local recharge processes. In the lower basin, groundwater exhibited greater transit times and longer flow paths. Low nitrate, chloride and sulphate concentrations found in groundwater indicate low leaching of fertilizers or urban wastewaters. Our results are focused to improve water resources and agricultural management plans in a dynamic tropical landscape.


Assuntos
Monitoramento Ambiental/métodos , Fenômenos Geológicos , Água Subterrânea/química , Isótopos/análise , Ciclo Hidrológico , Abastecimento de Água , Altitude , Costa Rica , Nitratos/análise , Rios/química , Estações do Ano , Clima Tropical , Poluentes Químicos da Água/análise , Recursos Hídricos/provisão & distribuição
14.
Rev. Bras. Saúde Mater. Infant. (Online) ; 20(3): 735-745, July-Sept. 2020. tab
Artigo em Inglês | Sec. Est. Saúde SP, LILACS | ID: biblio-1136444

RESUMO

Abstract Objectives: to identify dietary patterns (DP) and associated factors in first grade school-children in elementary schools in the South of Brazil. Methods: school-based cross-sectional study, with a non-probabilistic sample of 782 schoolchildren aged 6 to 8. Food intake was assessed by a food frequency questionnaire. DP were identified using the principal component analysis and the prevalence ratios were obtained by Poisson regression with a robust variance. Results: four DP were identified and accounted for 25.3% of the total variance: "fruit, vegetables and fish" (8.5%), "sweets and salty snacks" (7.0%), "dairy, ham and biscuits" (5.0%) and "common Brazilian food" (4.8%). After the adjustment, breakfast habit and lower frequency of meals in front of a screen increased the probability of adherence to a high consumption of DP of "fruit, vegetables and fish". The maternal schooling level was linearly and inversely associated with DP of "sweets and salty snacks" and "common Brazilian food", and positively related to the DP of "dairy, ham and biscuits". Schoolchildren with food inse-curity and sufficiently active had higher probability of adherence to DP of "common Brazilian food". Conclusions: four DP were identified and associated with food insecurity, maternal socioeconomic characteristics and schoolchildren's behavioral characteristics.


Resumo Objetivos: identificar padrões alimentares (PA) e fatores associados em escolares do primeiro ano do ensino fundamental de escolas municipais do sul do Brasil. Métodos: estudo transversal, de base escolar, com uma amostra não-probabilística de 782 escolares, de 6 a 8 anos. A ingestão alimentar foi avaliada por questionário de frequência alimentar. Os PA foram identificados através da análise de componentes princi-pais e razões de prevalência foram obtidas por regressão de Poisson com variância robusta. Resultados: foram identificados quatro PA que explicaram 25.3% da variância total: "frutas, verduras e peixe" (8,5%), "doces e salgadinhos" (7.0%); "laticínios, presunto e biscoitos" (5.0%) e "comum brasileiro" (4.8%). Após ajuste, hábito de realizar desjejum e baixa frequência de refeições em frente à tela aumentaram a probabilidade de adesão ao consumo elevado do PA "frutas, verduras e peixe". Escolaridade materna associou-se linear-mente e inversamente com o PA "doces e salgadinhos" e "comum brasileiro", e positiva-mente com o PA "laticínios, presunto e biscoitos". Escolares com insegurança alimentar e suficientemente ativos apresentaram maior probabilidade de adesão ao PA "comum brasileiro". Conclusões: identificaram-se quatro PA e foram observadas associações com insegu-rança alimentar, características socioeconômicas maternas e características comportamen-tais dos escolares.


Assuntos
Humanos , Pré-Escolar , Criança , Fatores Socioeconômicos , Ensino Fundamental e Médio , Análise de Componente Principal/métodos , Nutrição da Criança , Comportamento Alimentar , Insegurança Alimentar , Brasil , Distribuição de Poisson , Estudos Transversais , Ingestão de Alimentos
15.
Artigo em Inglês | MEDLINE | ID: mdl-32707973

RESUMO

The expanded use of information technology in education has led to the emergence of technostress due to a lack of adaptation to the technological environment. The purpose of this study is to identify the levels of technostress in primary and secondary education in 428 teachers using a RED-TIC questionnaire, of which skepticism, fatigue, anxiety, and inefficiency are the main components. For the empirical analysis of the data, principal component analysis (PCA) and confirmatory factor analysis (CFA) were used. The results show that 12% of Chilean teachers participating in the study feel techno-fatigued, 13% feel techno-anxious, and 11% present both conditions. Male teachers show a higher incidence of techno-anxiety and techno-fatigue than their female peers. It can be concluded that the questionnaire used is a reliable tool to evaluate the presence of technostress, and it manifests itself importantly in its components of techno-anxiety and techno-fatigue in Chilean teachers.


Assuntos
Pessoal de Educação , Instituições Acadêmicas , Chile , Análise Fatorial , Feminino , Humanos , Masculino , Professores Escolares , Inquéritos e Questionários
16.
J Phycol ; 56(2): 469-480, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31838754

RESUMO

Variability in thallus morphology is common in red seaweeds. Two co-occurring forms have been described for Chondracanthus chamissoi based mainly on blade width. To determine whether two distinct forms or a range of intermediate morphologies occur in C. chamissoi, thalli were collected from three localities in southern Chile in autumn-winter, repeating the sampling in one locality in spring and in summer. In each occasion, individual sporophytic and male and female gametophytic clumps were collected, and the longest blade with intact apex from each clump was evaluated. Blade length, width, density of spines, axis curvature and thickness, and pinnule length and width were evaluated in each blade. Principal components analyses separated two groups of thalli, one group with narrow, thick, and curved (concavo-convex) blades, with few spines consistent with f. lessonii, and another with broad, thin, and flat blades, with many spines consistent with f. chauvinii. These variables also had bimodal frequency distributions. Pinnule measurements were mainly associated with differences among sporophytes and gametophytes. Age (length), phase of the life cycle, and sex were not related to the forms. Furthermore, thalli of both forms were collected side by side in the study sites and throughout the year so the occurrence of the two forms was not attributable to local environmental conditions. In this species, secondary basal disks are produced after attachment of apexes to the substratum. These disks may produce blades with a modified morphology in a way similar to proliferations and regenerations described for Schottera nicaeensis.


Assuntos
Rodófitas , Alga Marinha , Chile , Células Germinativas Vegetais
17.
Artigo em Inglês | MEDLINE | ID: mdl-31593521

RESUMO

Coconut oil has properties that are beneficial to human health. It assists in reducing total cholesterol, triacylglycerol (TAG), phospholipids, low-density lipoprotein (LDL) cholesterol, and very low-density lipoprotein (VLDL) cholesterol in serum and tissues. So its production, and consequently consumption, have increased in recent years. However, it has been a target for intentional adulteration with lower priced oils and fats, such as soybean oil and palm kernel oil (PKO). Coconut oil (CO) and PKO have similar chemical and physical characteristics that make it difficult to verify adulteration of CO with PKO. This study demonstrates a simple, sensitive, and fast technique that uses direct infusion electrospray ionisation mass spectrometry (ESI-MS) in conjunction with principal component analysis (PCA), in order to detect CO adulterated with PKO. Among the seven commercial coconut oil samples analysed, three were adulterated with PKO. Therefore, the suggested direct infusion ESI-MS method can be used in routine analysis to guarantee the quality of coconut oil.


Assuntos
Óleo de Coco/química , Óleos de Plantas/análise , Óleo de Coco/análise , Óleo de Palmeira , Espectrometria de Massas por Ionização por Electrospray
18.
Parasit Vectors ; 12(1): 348, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300064

RESUMO

BACKGROUND: In the last decade, resistance to antimonials has become a serious problem due to the emergence of drug-resistant strains. Therefore, understanding the mechanisms used by Leishmania parasites to survive under drug pressure is essential, particularly for species of medical-veterinary importance such as L. amazonensis. METHODS: Here, we used RNA-seq technology to analyse transcriptome profiles and identify global changes in gene expression between antimony-resistant and -sensitive L. amazonensis promastigotes. RESULTS: A total of 723 differentially expressed genes were identified between resistant and sensitive lines. Comparative transcriptomic analysis revealed that genes encoding proteins involved in metabolism (fatty acids) and stress response, as well as those associated with antimony resistance in other Leishmania species, were upregulated in the antimony-resistant line. Most importantly, we observed upregulation of genes encoding autophagy proteins, suggesting that in the presence of trivalent stibogluconate (SbIII) L. amazonensis can activate these genes either as a survival strategy or to induce cell death, as has been observed in other parasites. CONCLUSIONS: This work identified global transcriptomic changes in an in vitro-adapted strain in response to SbIII. Our results provide relevant information to continue understanding the mechanism used by parasites of the subgenus Leishmania (L. amazonensis) to generate an antimony-resistant phenotype.


Assuntos
Gluconato de Antimônio e Sódio/farmacologia , Antiprotozoários/farmacologia , Resistência a Medicamentos/genética , Leishmania/efeitos dos fármacos , Leishmania/genética , Transcriptoma , DNA de Protozoário/genética , Perfilação da Expressão Gênica , Ontologia Genética , Fenótipo , Análise de Sequência de RNA , Regulação para Cima
19.
Int. j. morphol ; 37(2): 466-472, June 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1002244

RESUMO

The current young morphologist has a background in cellular and molecular biology, where the production of knowledge is very intense and rapid. However, as demonstrated in this review, quantitative methods in morphology, especially allometry, may be significant in demonstrating relationships between size and shape, ontogeny, and phylogeny. These themes are essential to the morphologist and should not be neglected because it improves the morphologists capacity for criticism and proposing projects. In this text, both ontogenetic and phylogenetic allometries in bivariate and multivariate studies are commented. Therefore, it is an initial text for those who have not yet been introduced to the topic, which gives the basis for being increased in the future, with more specific literature.


El joven morfólogo actual tiene una formación en biología celular y molecular, donde la producción de conocimiento es muy intensa y rápida. Sin embargo, como expusimos en esta revisión, métodos cuantitativos en morfología, en especial la alometría, pueden ser significantes en demostrar relaciones entre el tamaño y la forma, la ontogenia y la filogenia. Estos temas son importantes para el morfólogo y no deben ser descuidados porque mejora la capacidad de crítica y la propuesta de proyectos. En este texto, presentamos la alometría ontogenética y la filogenética, en estudios bivariados y multivariados. Por lo tanto, es un texto inicial para quienes aún no se han introducido al tema y que dará las bases para ser acrescentado en el futuro, con literatura más específica.


Assuntos
Filogenia , Análise Multivariada , Biometria/métodos
20.
Ci. Anim. bras. ; 20: e-46898, Apr. 29, 2019. tab, graf
Artigo em Português | VETINDEX | ID: vti-21199

RESUMO

O objetivo deste trabalho foi avaliar a interação entre sistemas produtivos e estações do ano sobre a qualidade do leite bovino. Três propriedades foram avaliadas mensalmente, durante as estações, em quatro graus de especialização dos sistemas de produção: altamente especializado, especializado, semiespecializado e não especializado. Em termos de qualidade do leite, consideraram-se os teores de gordura, proteína, sólidos totais, contagem de células somáticas, contagem bacteriana total, acidez titulável em graus Dornic, densidade, índice crioscópico, estabilidade ao alizarol, potencial de hidrogênio (pH) e teste de redução do azul de metileno. Além destes, devido à sua importância para o rendimento industrial dos produtos lácteos de base proteica, foi realizado o fracionamento da proteína total do leite em equivalente proteico do nitrogênio não proteico, da proteína verdadeira e da caseína. A acidez Dornic foi maior na primavera e no inverno, enquanto os valores mais elevados de contagem de células somáticas foram no verão. Os teores de proteína total e proteína verdadeira foram menores durante o verão e elevaram-se os sólidos totais no outono. Com a diminuição dos níveis de especialização das propriedades rurais, observaram-se aumento na contagem bacteriana total e diminuição do nitrogênio não proteico. A densidade apresentou comportamento inverso ao da gordura, enquanto o potencial de hidrogênio (pH) se expressou de modo antagônico à acidez titulável. Na análise multivariada dos dados, foi possível identificar as combinações entre estratos produtivos e estações do ano que apresentavam a melhor qualidade da proteína do leite. Nesse sentido, todos os arranjos de sistemas de produção com o outono, o sistema altamente especializado no inverno, o semiespecializado no verão e o especializado na primavera tiveram qualidade proteica positiva, destacando-se pelas menores...(AU)


The objective of this work was to evaluate the effect of the interaction between production systems and seasons on physical-chemical and microbiological qualities of bovine milk. Three farms were assessed monthly, along the seasons, for four specialization levels of the production systems: highly specialized, specialized, partially specialized, and non-specialized. In terms of milk quality, the levels of fat, protein, total solids, somatic cell count, total bacterial count, titratable acidity in degrees Dornic, density, cryoscopic index, alizarol stability, potential of hydrogen (pH) and methylene blue reduction test. In addition, due to their importance for the industrial yield of protein-based dairy products, total milk protein fractionation was performed in protein equivalent of non-protein nitrogen, true protein and casein.The milk Dornic acidity was higher in spring and winter, while the highest somatic cell count values were in the summer. Total and true protein levels were lower during the summer and total solids increased in the autumn. With the decrease in the levels of specialization of farms, there was an increase in total bacterial count and decrease in non-protein nitrogen. The density presented an inverse behavior to that of the fat while the hydrogen potential (pH) was expressed in a way antagonistic to the acidity. In the multivariate analysis of the data it was possible to identify the combinations between production strata and stations that presented the best milk protein quality. In this sense, all the arrangements of production systems with autumn, winter highly specialized, summer partially specialized, spring specialized had positive protein quality, being highlighted by the smaller of somatic cells counts in the spring partially specialized combination.(AU)


Assuntos
Animais , Feminino , Bovinos , Leite/química , Leite/microbiologia , Fenômenos Químicos , Estações do Ano , Criação de Animais Domésticos/métodos , Análise Multivariada , Qualidade dos Alimentos
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