Pesquisa | SciELO

5-Hydroxymethylfurfural (HMF) can be obtained from the dehydration of monosaccharides present in biomass, which helps add value to the raw material. The present work sought to study the relationship between the parameters of biomass characterization, including the content of reducing sugars, total soluble solids and the mid-infrared (MIR) and near-infrared (NIR) spectra, and the formation of HMF after synthesis. A thorough analysis was conducted in order to evaluate the residual agricultural biomass samples from sugarcane bagasse, corn stover, cassava branch, banana pseudostem and mango fruits after the drying (45 °C maximum) and ball mill grinding pre-processing procedure. HMF synthesis was performed using 0.50 mol L-1 HCl and n-butanol as extracting solvent. The analytical quantification of HMF and furfural (co-product of synthesis) was performed using high-performance liquid chromatography coupled to diode-array detector (HPLC-DAD). The highest efficiency of the synthesis of HMF was observed for the mango fruits (55.0 kg ton-1) and sugarcane bagasse biomass (47.5 kg ton-1) samples. The application of data fusion and principal component analysis (PCA) allowed us to identify the samples with greater potential for HMF synthesis.

https://doi.org/10.21577/0103-5053.20230020

Revisiting global cognitive and functional state 13 years after a clinical trial of lithium for mild cognitive impairment
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Damiano, Rodolfo Furlan

; Loureiro, Julia Cunha

; Pais, Marcos Vasconcelos

; Pereira, Rodrigo Furtado

; Corradi, Marina de Menezes

; Di Santi, Talita

; Bezerra, Gustavo Antonio Marcolongo

; Radanovic, Márcia

; Talib, Leda Leme

; Forlenza, Orestes Vicente

Brazilian Journal of Psychiatry

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Jan 2023, Volume 45 Nº 1 Páginas 46 - 49

Resumo: En | Texto: En | PDF: En

Objectives: To re-evaluate a sample of older adults enrolled in a randomized controlled trial of lithium for amnestic mild cognitive impairment (MCI) after 11 to 15 years, re-assessing their current (or last available) global cognitive and functional state. Methods: We recalled all former participants of the Lithium-MCI trial conducted by our group between 2009 and 2012 to perform a single-blinded, cross-sectional evaluation of their global clinical state to compare the long-term outcome of those who received lithium vs. those who received placebo. Results: Of the original sample (n=61), we were able to reach 36 participants (59% of retention), of whom 22 had previously received lithium (61% of the recall sample) and 14 (39%) had received placebo. Since 30.5% of the recalled sample was deceased, psychometric data were collected only for 69.5% of the participants. We found statistically significant differences in current mean Mini Mental State Examination score according to previous treatment group (25.5 [SD, 5.3] vs. 18.3 [SD, 10.9], p = 0.04). The lithium group also had better performance in the phonemic Verbal Fluency Test than the control group (34.4 [SD, 14.4] vs. 11.6 [SD, 10.10], p < 0.001). Differences in these measures also had large effect sizes, as shown by Cohen’s d values of 0.92 and 1.78, respectively. Conclusion: This data set suggests that older adults with amnestic MCI who had been treated with lithium during a previous randomized controlled trial had a better long-term global cognitive outcome than those from a matched sample who did not receive the intervention.

https://doi.org/10.47626/1516-4446-2022-2767

A comparison between ultrasonography and single-phase computed tomography for preoperative assessment of solid abdominal tumors in children
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Lucena, Iara Regina Siqueira

; Chedid, Márcio Fernandes

; Isolan, Paola Santis

; Takamatu, Eliziane Emy

; Lucena, Ronaldo Albé

; Feier, Flavia Heinz

; Furtado, Álvaro Porto Alegre

; Fraga, Jose Carlos Soares de

Jornal de Pediatria

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Jan 2023, Volume 99 Nº 1 Páginas 17 - 22

Resumo: En | Texto: En | PDF: En

Abstract Objective: This study aimed to estimate the performance of single-phase-enhanced computed tomography and ultrasonography examinations in the preoperative evaluation of solid abdominal tumors and their relationship with relevant adjacent structures in children. Methods: This retrospective study included 50 pediatric patients with malignant solid abdominal tumors treated with surgical resection between 2009-2017. Preoperative computed tomography and ultrasonography were compared to operative findings (gold standard) in the diagnosis of invasion or encasement of adjacent structures. Accuracy, sensitivity, specificity, and positive and negative predictive values were evaluated. Results: Renal (20.4%) and neuroblastic (19.4%) tumors were the most common. Complete surgical resection with negative margins was achieved in 44 (88%) patients. The comparison between single-phase-enhanced computed tomography and ultrasonography findings showed the following results: sensitivity = 90.3% vs 86.6%, specificity = 86.8% vs 94.6%, negative predictive value = 95.3% vs 94.4%, positive predictive value = 75.3% vs 86.9%, and accuracy = 87.9% vs 92.2%. The correlation (kappa index) between computed tomography and ultrasonography examinations was 0.72 (p < 0.001). In 14% (7/50) of the patients, the invasion of adjacent structures was diagnosed by ultrasonography but not by computed tomography (1 patient had 2 invaded structures).

https://doi.org/10.1016/j.jped.2022.05.003

Viability and resistance of Lacticaseibacillus rhamnosus GG to passion fruit beverages with whey protein isolate
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Guerra, Adriana Couto

; Martins, Eliane Maurício Furtado

; Paula, Daniele de Almeida

; Leite Júnior, Bruno Ricardo de Castro

; Silva, Roselir Ribeiro da

; Franco, Frederico Souza Lima Caldoncelli

; Martins, Maurilio Lopes

; Oliveira, Gabriel Henrique Horta de

Brazilian Journal of Food Technology

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2023, Volume 26 elocation e2022051

Resumo: En | Texto: En | PDF: En

Abstract This study characterized the beverage of passion fruit and whey protein added with Lacticaseibacillus rhamnosus GG (LGG). The acidity, pH, soluble solids, protein, phenolic compounds, and color of the sample did not differ during the 28 days at 5°C. The LGG counts in the beverage remained >7.70 log CFU/mL during the evaluation period. However, the LGG count was significantly reduced after the in vitro simulated gastrointestinal tract (GIT) evaluation (reduction of 5 logarithmic cycles after processing). On the other hand, the LGG resistance to GIT increased during the shelf-life of the beverage (LGG count of ~ 4.0 log CFU/mL after 28 days). In addition, the LGG count after GIT increased by approximately 2.0 logarithmic cycles when microencapsulation and fermentation technologies were used in beverage processing. Thus, the product has the potential to be commercialized, due to high viability of LGG use to increase the resistance of LGG to GIT.

https://doi.org/10.1590/1981-6723.05122

Experimental and Theoretical Studies of Tailor-made Schiff Bases as Corrosion Inhibitors for Carbon Steel in HCl
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Furtado, Luana B.

; Leoni, Gabriel B.

; Nascimento, R. C.

; Santos, Pedro Henrique C.

; Henrique, Fábio J. F. S.

; Guimarães, Maria José O. C.

; Brasil, Simone L. D. C.

Materials Research

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2023, Volume 26 elocation e20220398

Resumo: En | Texto: En | PDF: En

Abstract Strong acids used in industrial applications as cleaning, descaling, among others, can severely damage metallic structures, requiring corrosion inhibitors to diminish or avoid these issues. Since many conventional compounds used for this purpose may result in environmental and human health issues, eco-friendly compounds such as Schiff bases have been recently investigated. The synthesis of three novel Schiff bases (SBs) was confirmed by infrared spectroscopy (FTIR) and hydrogen nuclear magnetic resonance (1H-NMR). Weight loss measurements were carried out in 1 M HCl over 303K-333K. Furthermore, the combination of these compounds with a surfactant improved the efficiencies, reaching an efficiency of 93%. Optical and scanning electron microscopies confirmed the reduced roughness and pit depths of carbon steel samples. Density-functional theory calculations for neutral forms of SBs revealed that the geometrical and the energetical parameters are similar for the three studied SBs. The geometrical results exhibited more planar structures of protonated species, improving the chemical and physical interactions between aromatic rings and metallic atoms.

https://doi.org/10.1590/1980-5373-mr-2022-0398

Needle visualization during ultrasound-guided puncture: image optimization
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Brasileiro, Augusto Cézar Lacerda

; Silva, Aeudson Víctor Cunha Guedes e

; Garcia, Ariana Lacerda

; Furtado, Beatriz Ribeiro Coutinho de Mendonça

; Araújo Filho, Frederico Augusto Polaro

; Diniz, Laís Nóbrega

; Silva, Leonardo César Maia e

; Lima, Lorena Agra da Cunha

Jornal Vascular Brasileiro

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2023, Volume 22 elocation e20230038

Resumo: En Pt | Texto: En Pt | PDF: En | PDF: Pt

Abstract Background Obtaining an adequate image of the needle by ultrasound reduces complications resulting from punctures, increasing patient safety and reducing hospitalization costs. Objectives To verify human perception in relation to number of pixels, while also identifying the best puncture angle and which needle should be used, and to evaluate whether there is a difference if needle visualization software is used. Methods 20 images were analyzed by 103 students who classified them as being sufficient or insufficient and were compared with the quality observed using photoshop. We evaluated whether there were differences between puncture angles of less than 45º and more than 45º, between IV catheter and introducer needles, and between images obtained with and without visualization software. Results There was a higher percentage of sufficient ratings for images those that had more than 60 pixels and when the puncture angle was less than 45º, with significant associations between students’ evaluations and each of these groups (p < 0.001). The percentages of images classified as sufficient were higher for images in which a IV catheter was used and also higher for those using the needle visualization software, with significant associations between the results for students’ classifications and each of these groups (p < 0.001). Conclusions The human eye classifies an image as sufficient according to higher numbers of pixels. Images of punctures at angles smaller than 45º in relation to the surface, of punctures performed with a IV catheter, and when using specific visualization software are also better detected by the human eye.

Resumo Contexto A obtenção de uma imagem adequada da agulha pelo ultrassom diminui complicações decorrentes de punções, trazendo segurança para os pacientes e diminuindo custos com hospitalização. Objetivos Verificar a percepção do olho humano em relação aos pixels, identificar qual o melhor ângulo da punção e qual agulha deve ser utilizada e avaliar se há diferença com o uso de software de visualização de agulha. Métodos Vinte imagens foram analisadas por 103 alunos, que as classificaram como sendo suficientes ou insuficientes, e comparadas com a qualidade observada pelo photoshop. Avaliou-se se havia diferença entre punções com menos de 45º e mais de 45º, entre cateter EV e agulha introdutora e entre imagens obtidas com e sem software de visualização. Resultados Houve um percentual mais elevado de imagens suficientes entre aquelas que tinham mais de 60 pixels e quando o ângulo era menor que 45º, com associação significativa entre a classificação das avaliações pelos alunos e cada um desses grupos (p < 0,001). O percentual de imagens suficientes foi maior nas imagens realizadas com cateter EV e naquelas que utilizaram o software de visualização da agulha, ocorrendo associação significativa entre os resultados da classificação pelos alunos e cada um desses grupos (p < 0,001). Conclusões O olho humano classifica a imagem como sendo suficiente de acordo com a maior quantidade de pixels. Imagens puncionadas com ângulos menores que 45º em relação à superfície, realizadas com cateter EV e utilizando software específico de visualização também são mais bem detectadas pelo olho humano.

https://doi.org/10.1590/1677-5449.202300382

Herpetofauna of protected areas in the Caatinga VIII: An updated checklist for the Serra das Confusões region with new data from Serra Vermelha, Piauí, Brazil
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Marques, Ricardo

; Garda, Adrian A.

; Furtado, Adriana P.

; Bruinjé, Andre C.

; Protázio, Arielson dos S.

; de Carvalho, Breno F.

; Vieira, Cecília R.

; Gomes, Dandara

; Pantoja, Davi L.

; Figueiredo, Diainara da S.

; Shepard, Donald B.

; Camurugi, Felipe

; Coelho, Felipe E. A.

; Magalhães, Felipe M.

; Caetano, Gabriel H. O.

; Colli, Guarino R.

; Paulino, Henrique M.

; Carvalho, Izabelle T. S.

; Graciene, Joedma

; Alvarenga, Júlio M.

; Clay, Natalie A.

; Albuquerque, Ralph L.

; Bosque, Renan J.

; Faria, Renato

; da Silveira-Filho, Ricardo R.

; Mângia, Sarah

; Cavalcante, Vitor H. G. L.

; Vieira, Washington L. S.

; da Silva, Willianilson P.

; Soares, Yan F. F.

; Mesquita, Daniel O.

Biota Neotropica

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2023, Volume 23 Nº 4 elocation e20231520

Resumo: En Pt | Texto: En Pt | PDF: En | PDF: Pt

Abstract It is repeatedly stressed the need to characterize the extant biodiversity in tropical ecosystems. However, inventory studies are still progressing slowly in dry ecosystems, leading to the underestimation of their true biodiversity and hindering conservation efforts. In this study, we present primary and secondary data, along with an updated list of amphibians and reptiles from two localities in the São Francisco-Gurguéia region in Piauí. Additionally, we compare the species composition between nine areas within the Caatinga, which were sampled using standardized methods over the past ten years, to examine broader spatial patterns of community composition. To survey reptiles and amphibians, we employed similar methods and sampling efforts in two areas within the Serra das Confusões National Park (SCNP) region. Our surveys recorded a total of 73 species of amphibians and reptiles, of which 24 are new distribution records for the SCNP region. Consequently, our findings increase the known herpetofauna in the region to 94 species. Despite their proximity, the two sites in the SCNP region exhibited only 42% similarity in species composition, and they differed significantly from other areas within the Caatinga. Furthermore, even the closer Caatinga areas presented differences in species composition, highlighting the necessity to evaluate biodiversity across the landscape and contribute to understanding biogeographic patterns.

Resumo É repetidamente enfatizada a necessidade de caracterizar a biodiversidade vivente em ecossistemas tropicais. No entanto, os estudos de inventário ainda estão progredindo lentamente em ecossistemas secos, levando à subestimação de sua verdadeira biodiversidade e dificultando os esforços de conservação. Neste estudo, apresentamos dados primários e secundários, juntamente com uma lista atualizada de anfíbios e répteis de duas localidades na região de São Francisco-Gurguéia, do Piauí. Além disso, comparamos a composição de espécies entre nove áreas dentro da Caatinga, que foram amostradas usando métodos padronizados nos últimos dez anos, para examinar padrões espaciais mais amplos de composição da comunidade. Para estudar répteis e anfíbios, utilizamos métodos e esforços de amostragem semelhantes em duas áreas na região do Parque Nacional da Serra das Confusões (PNSC). Nossos levantamentos registraram um total de 73 espécies de anfíbios e répteis, das quais 24 são novos registros de distribuição para a região do PNSC. Consequentemente, nossos resultados aumentam a herpetofauna conhecida na região para 94 espécies. Apesar da proximidade, os dois locais na região do PNSC exibiram apenas 42% de similaridade na composição de espécies e diferiram significativamente de outras áreas dentro da Caatinga. Mesmo áreas mais próximas da Caatinga apresentaram diferenças na composição de espécies, destacando a necessidade de avaliar a biodiversidade em toda a paisagem e contribuir para a compreensão de padrões biogeográficos.

https://doi.org/10.1590/1676-0611-bn-2023-1520

Determination of cyanide in whole seeds and brans of linseed (Linum usitatissimum Linn) by molecular spectrophotometry
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Pereira, Marcelle Leandro da Silva

; Souza, Rita de Cássia Paulino de

; Medeiros, Juliana Vilar Furtado de

; Brito, George Queiroz de

; Schwarz, Aline

Brazilian Journal of Pharmaceutical Sciences

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2023, Volume 59 elocation e23059

Resumo: En | Texto: En | PDF: En

Abstract The addition of linseed (Linum usitatissimum Linn) in the diet, as a functional food, has increased over the years. However, it possesses cyanogenic glycosides. This study aimed to quantify and compare cyanide concentration in whole seed and bran of brown and golden types to establish a safe limit of intake. Three commercial labels, from brown and golden whole seed types (Ab, Ag, Bb, Bg, Cb and Cg), and six commercial labels of brown and golden bran (1b, 2g, 3g, 4b, 5g, and 6b), were selected, totalizing twelve samples. Total cyanide concentration was quantified by a colorimetric method employing alkaline picrate, after acid hydrolysis. The whole seed cyanide values were between 348.4 and 473.20 µg/g and the bran cyanide values were between 459.53 and 639.35 μg/g. The analyzed bran presented increased cyanide concentrations than the whole seeds with no differences between brown and golden types. Food able to produce cyanide less than 90 µg/kg body weight, daily, is considered secure for consumption. Considering this limit and analyzed samples, it is safe to eat approximately two tablespoons of seeds or one tablespoon of bran. These results point out the importance of cyanide amount daily intake information to be in linseed packaging, to ensure secure consumption.

https://doi.org/10.1590/s2175-97902023e23059

10.

First Evaluation of the Brazilian Advanced Life Support Training (TECA A)
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Furtado, Fabrício Nogueira

; Carvalho, Antonio Carlos de Camargo

; Gonçalves Junior, Iran

; Canesin, Manoel Fernandes

; Timerman, Sergio

; Gonçalves, Rodrigo Marques

; Alfieri, Daniela Frizon

; Almeida, Dirceu

International Journal of Cardiovascular Sciences

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2023, Volume 36 elocation e20220199

Resumo: En | Texto: En | PDF: En

Abstract Background Cardiac arrest (CA) is a common condition associated with high mortality. The Brazilian advanced life support training TECA A (Treinamento em Emergências Cardiovasculares Avançado — Advanced Cardiovascular Emergency Training) was created to train healthcare professionals in the management of CA. However, there are no studies evaluating the effectiveness of TECA A. Objective To assess the impact of TECA A on the management of CA using a simulated CA situation. Methods Fifty-six students underwent a simulated case of CA in a manikin. The students’ performance in the management of CA was assessed for the time to first chest compression and defibrillation and for a global assessment score using a structured tool. These items were assessed and compared before and after the TECA A. Exclusion criteria were previous participation in CA trainings and absence from class. Categorical variables were compared using the McNemar test and quantitative variables using the Wilcoxon test. All tests were two-tailed, and statistical significance was set at p < 0.05. Results Compared with before TECA A, median global assessment scores were higher after TECA A (pre-training: 4.0 points [2.0-5.0] vs. 10 points [9.0-10.0]; p<0.001), the time to start chest compressions was shorter (pre-training: 25 seconds [15-34] vs. 19 seconds [16.2-23.0]; p=0.002) and so was the time to defibrillation (pre-training: 82.5 seconds [65.0-108.0] vs. 48 seconds [39.0-53.0]; p<0.001). Conclusions The TECA A promoted a higher adherence to cardiopulmonary resuscitation (CPR) guidelines and a reduction in the time elapsed from CA to first chest compression and defibrillation.

https://doi.org/10.36660/ijcs.20220199

11.

Tourette syndrome and multiple sclerosis: a case report sclerosis
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Gondim, Francisco de Assis Aquino

; Leitão, Antônio Miguel Furtado

; Araújo Melo, Leonardo José Rodrigues de

; Araújo, Ineusi Teixeira de

Brazilian Journal of Psychiatry

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2023, Volume 45 Nº 3 Páginas 299 - 300

Resumo: En | Texto: En | PDF: En

https://doi.org/10.47626/1516-4446-2022-3024

12.

Yang-Mills-Shaw e as equações de Maxwell não-Abelianas
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Furtado, J.

; Helaÿel-Neto, J.A.

Revista Brasileira de Ensino de Física

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2022, Volume 44 elocation e20220045

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

Este artigo tem como objetivo principal apresentar, de maneira sucinta e intuitiva, aspectos fundamentais da construção e do do desenvolvimento da Teoria de Yang-Mills-Shaw. Partindo do paradigma do Eletromagnetismo de Maxwell, construímos, por analogia, a teoria para campos vetoriais não-Abelianos e sua interação com a matéria. Para tal, estendemos o grupo U ( 1 ) do eletromagnetismo para o grupo SU ( N ) e escrevemos as equações tipo-Maxwell para o caso de simetrias não-Abelianas, definindo os campos elétricos e magnéticos associados para a simetria SU ( N ).

This paper sets out to present, in a brief and intuitive way, fundamental aspects on the construction and formulation of the Yang-Mills-Shaw Theory. Starting off from the paradigm of Maxwell Electromagnetism, we build up, by analogy, the formulation for nonabelian vector fields and their (gauge) interactions with matter. In order to do so, we extend U ( 1 ) to the SU ( N ) group and write down the nonabelian extension of the Maxwell equations by now defining the electric and magnetic fields for the SU ( N )-symmetry.

https://doi.org/10.1590/1806-9126-rbef-2022-0045

13.

Methodological approach and general guidelines to geochemical mapping and background-baseline analysis for environmental assessment: a case study in the Carajás Mineral Province, Brazil
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Souza-Filho, Pedro Walfir Martins

; Sahoo, Prafulla Kumar

; Silva, Marcio Sousa da

; Dall’Agnol, Roberto

; Medeiros Filho, Carlos Augusto

; Leite, Alessandro Sabá

; Ferreira Júnior, Jair da Silva

; Nascimento Junior, Wilson da Rocha

; Silva, Géssica da Silva e

; Salomão, Gabriel Negreiros

; Sarracini, Fabiana

; Silva Junior, Renato Oliveira

; Costa, Marlene Furtado da

Brazilian Journal of Geology

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2022, Volume 52 Nº 4 elocation e20220018

Resumo: En | Texto: En | PDF: En

Abstract We present this manuscript as a methodological approach and general guidelines for geochemical mapping and background/baseline projects for environmental assessment in tropical areas. A case study was carried out in the Itacaiúnas River watershed (IRW), Eastern Amazon, to fill in a gap in knowledge on the distribution of chemical elements, particularly those potentially toxic, in the near-surface environment of the area. The high-impact results of this research project revealed the need for similar scientific investigation across the globe with the implementation of a systematic methodology. The study shows, for example, the importance of well-planned field activities, multi-medium sampling, analytical methods, laboratory procedures, database construction, and general aspects of data processing and statistical treatment. The importance of this contribution is that it can be used as a reference in support of geospatial analysis in research within the scope of geochemical mapping and background-baseline projects. The database is accessible through a web-based geographic information system front-end; a Geochemical Atlas of the IRW will be available as soon as possible.

https://doi.org/10.1590/2317-4889202220220018

14.

Teoria de Grupos e o Papel das Simetrias em Física
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Furtado, J.

; Helaÿel-Neto, J. A.

Revista Brasileira de Ensino de Física

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2021, Volume 43 elocation e20200338

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

Este artigo tem como objetivo principal apresentar, de maneira sucinta e intuitiva, aspectos fundamentais da teoria de grupos, estabelecendo sua relação com a ideia de simetria, traçando um paralelo com o desenvolvimento da mecânica quântica e da física de partículas. Buscamos abordar este tema, que é frequentemente negligenciado em cursos de graduação, partindo sempre do conceito de invariância de uma dada quantidade física de interesse para, só então, introduzir a ideia de grupo de simetria.

This paper sets out to present, in a brief and intuitive way, fundamental aspects of group theory, establishing its relation with the idea of symmetry, drawing a parallel with the development of quantum mechanics and particle physics. We try to approach this topic, which is frequently neglected in undergraduate courses, always starting from the concept of invariance of a given quantity of interest to, only after that, introduce the idea of a symmetry group.

https://doi.org/10.1590/1806-9126-rbef-2020-0338 1597 downloads

15.

Effects of soccer training during preseason on physical and physiological variables in youth soccer players
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Rodrigues Júnior, Jefferson Fernando Coelho

; Dias-Filho, Carlos Alberto Alves

; Oliveira Júnior, Mário Sevílio de

; Sena, Carlan da Silva

; Ferreira, Andressa Coelho

; Mendes, Thiago Teixeira

; Costa, Herikson Araújo

; Soares Junior, Nivaldo de Jesus Silva

; Marques, Raphael Furtado

; Mostarda, Cristiano T.

; Dias, Carlos J.

Motriz: Revista de Educação Física

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2021, Volume 27 elocation e1021000921

Resumo: En | Texto: En | PDF: En

Abstract Aim: This study aimed to explore the effects of a training program during the pre-season on aerobic and anaerobic performance, hemodynamics, autonomic variables, and sleep quality in youth soccer players. Methods: Nineteen athletes, with an average age of 17 ± 1 years, participated in the study. The multicomponent training protocol was divided into technical, tactical, and physical practice for four weeks. The cardiac autonomic modulation was obtained through an electrocardiogram and blood pressure values were measured by a sphygmomanometer. The athletes answered the Pittsburgh questionnaire that assessed sleep patterns and issues. The VO2max was analyzed using the Intermittent Recovery Test Yo-Yo level 1. The RAST test was used to assess anaerobic power. Results: There was improvement in Heart Rate Variability (HRV) indicated by the increase in indexes, mean square root of the differences between normal cycles (RMSSD), low frequency increase (LF) (p = 0.04; d = 0.70), high frequency decrease (HF) (p = 0.01; d = 1.02) and the LF / HF sympathovagal index (p = 0.03; d = 0.70), variables related to faster recovery. An improvement in the components of sleep duration (p = 0.03) and quality (p = 0.02) of baseline and post-intervention sleep was also observed. Conclusion: The four-week multicomponent protocol contributed to improving VO2max, improving fatigue rates, quality of sleep, and maximum power. Additionally, we observe that youth soccer athletes had physiological and hemodynamic adaptations that resulted in an improvement in cardiac autonomic modulation and sleep patterns after four weeks of training.

https://doi.org/10.1590/s1980-65742021000921 169 downloads

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