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    O Jogo de Realidade Alternada Curto (Short ARG) como estratégia de discussão de conceitos químicos em nível superior
    (2020-02-17) Deus, Thiago Cardoso de; Soares , Márlon Herbert Flora Barbosa
    This paper presents the application of a Short ARG built to be applied in a single class, instead of a longer interval, as it is common in strategies such as ARG. ARGs are games based on role-playing experiences that involve role playing using a particular place, in this case, two classrooms and an education lab. Whereas ARG’s characters are the participants/ players themselves, in this study, they were the Chemistry undergraduate students. The students/players were aimed of various clues and moments involving chemical concepts to find a lost student. We could notice ARG can be a teaching strategy, we mean, an alternative for conceptual discussion in the classroom as well as a diagnostic and formative assessment tool, characteristic of the use of games and recreational activities in teaching scientific concepts.
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    Abordagem interdisciplinar nos capítulos de equilíbrio químico e eletroquímica em livros didáticos de Química aprovados pelo PNLD/2008/2012/2015/2018
    (2022-02-23) Leite, Maycon Batista; Soares, Márlon Herbert Flora Barbosa
    From different theoretical perspectives of interdisciplinary approach, we apprehend the one that aims the formation of the subject with critical and political consciousness of social reality. The Didactic Book is the most relevant didactic resource in the teaching chemistry in Brazil and the PNLD (National Textbook Program) presents as its main purpose, to impose a minimum quality standard on Didactic Books offered in publishing Market. We investigated which are the prospects of an interdisciplinary approach that the authors of the Chemistry Didactic Books of PNLD/2008/2012/2015/2018 present in Chemical Equilibrium and Electrochemistry chapters of their respective works. We used Bardin’s content analysis method, which provided us with elements for the constitution of three categories of interdisciplinary analysis. The research pointed out that the Didactic Books are more focused on the approach of conceptual interactions inherent to scientific Knowledge as academic and instrumental interdisciplinarity. One of the main results of this work shows that only one of the ten works analyzed reached interdisciplinarity as an understanding of contexts and issues inherent to social reality. Based on results like these, this research can contribute to the expansion of the understanding of interdisciplinarity and the qualification process of science textbooks, which implies future evaluators committed to the transformative perspective, avoiding the return of works or contents outdated by ignorance of the concept of interdisciplinarity.
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    Análise de elementos corruptivos dos jogos educativos publicados na QNEsc (2012-2021) na perspectiva de Caillois
    (2022-11) Soares, Márlon Herbert Flora Barbosa; Rezende, Felipe Augusto de Mello
    The present work aims to identify possible corruptive elements in works that use games for the teaching of Chemistry/Science published in the QNEsc from 2012-2021, and to discuss how corruptions impact pedagogical games and their relationship with the philosophical references of games. The research was carried out through a document analysis, categorized a posteriori in: corruption of the agon; from mimicry; from paidia; and “absence” of corruption. There were works that corrupted paidia due to the data collection and analysis instruments used by teachers. The corruption of the agon highlighted how important and decisive the rules are in games, showing how much teachers do not understand them. 72.7% of the articles examined have corruption directly or indirectly linked to the actions of teachers, data that reinforce the need for greater theoretical, philosophical and methodological deepening of the game.
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    Análise teórica e epistemológica de jogos para o ensino de Química publicados em periódicos científicos
    (2019-12-12) Rezende, Felipe Augusto de Mello; Soares, Márlon Herbert Flora Barbosa
    In recent years there has been a considerable increase in the number of publications involving the application of games for teaching Chemistry. However, such publications are not necessarily accompanied by adequate theoretical frameworks or, when used, are not directly related to teaching and learning issues. Thus, we intend to analyze a series of scientific articles from various journals between the years 2000 to 2016 in order to reveal the use of theoretical references of teaching and learning, and, from this analysis, to verify how games have been structured, in relation not only to the adopted references, but also to the students' learning. The results point to the need to discuss the role of gaming as a teaching and learning methodology, since the use of epistemological references is still very incipient, and few theoretical concepts are explored by the researchers. The vast majority of games use the epistemological references as a learning methodology, since such conceptions are listed with the purpose of confirming the concepts worked in the lectures, which has not contributed to the students' learning.
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    Jogos na educação em Química: uma pesquisa bibliográfica em um periódico científico brasileiro entre 1995 e 2021
    (2022) Silva, Cleberson Souza da; Soares, Márlon Herbert Flora Barbosa
    Este trabajo de investigación bibliográficatuvo como objetivo analizar y problematizar el contenido de artículos que involucran el tema de juegos publicados en los últimos 27 años por la revista Química Nova na Escolacon el fin de señalar algunas de las principales características y peculiaridades más relevantes de tales publicaciones. Para ello, realizamos una investigación bibliográfica cualitativa en todos los números y volúmenes de la mencionada revista hasta el año 2021, en la que encontramos 37 artículos que abordaban la temática mencionada.Así, estudiamos dichos artículos a través de la técnica de análisis de contenido, que luego surgieron de las siguientes categorías: i)materias escolares con foco en el contenido abordadoen los juegos; ii)año de publicación y finalidad del juego; y iii)sección de la revista y lugar de origen de los autores y coautores de los artículos. De esta forma, con el estudio de estas categorías, fue posible comprender, en los textos analizados, los siguientes aspectos: disciplina abordada, contenido trabajado, objetivo del juego, año de publicación, sección de Química Nova na Escolaen la que se ue publicado y lugar de origen de los autores y coautores de los artículos. Por lo tanto, se constató,entre otras cosas, que la mayoría de los artículos analizados abordan contenidos tradicionales de Química de uso común en la Enseñanza Media en Brasil. Además, la mayoría de los juegos presentes en los artículos tenían como objetivo permitir un aprendizaje efectivo de Química, así como muchos de los artículos analizados provenían de grandes centros urbanos brasileños, como Goiás, Distrito Federal y Río de Janeiro, en detrimento de otras províncias como Amapá y Piauí, por ejemplo.
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    E a parte da história que não é contada? Reflexões feministas sobre a história da ciência
    (2022-12-13) Lima, Ana Luiza do Prado; Soares, Márlon Herbert Flora Barbosa
    Understanding the importance of gender discussions and women’s in science, this article proposes, from a feminist perspective, to presente the history of some scientists, especially the first women accepted in western universities. The present study has a theoretical character and aims to analyze some aspects and periods of scientific construction, as a way of highlighting the process of exclusion and invisibility of scientists in the highlighted periods. It is salutary to point out that the choice for the feminist approach to the historical analysis of science was mainly due to the political, social and intersectional character of feminist movements. From the above, it was possible to verify the contradiction in the ideals of neutrality, objectivity and exemption from political/religious, on which the scientific construction was based, especially in terms of gender discussions. Faced with a scientific construction that made invisibilized and excluded scientists, in addition to having their knowledge appropriated, Science still remains within misogynistic and sogregating parameters. Therefore, this research proposes the urgency of reflections and gender discussions in scientific communities.
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    “pySiRC”: machine learning combined with molecular fingerprints to predict the reaction rate constant of the radical-based oxidation processes of aqueous organic contaminants
    (2021-09-02) Sanches Neto, Flávio Olimpio; Silva, Jefferson Richard Dias da; Queiroz Júnior, Luiz Henrique Keng; Silva, Valter Henrique Carvalho
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    Robótica educacional, ensino de Química e aprendizagem cooperativa: uma proposta para o curso de ensino superior em Engenharia Civil
    (2022-05-26) Pinheiro, Ricardo Silverio Gomes; Soares, Márlon Herbert Flora Barbosa
    Students, generally, are afraid of studying chemistry because they understand that it is a very complex area of knowledge and that it doesn’t has use in daily lives and in intended profession, which is a problem we identified in a Civil Engineering course. With this, we proposed a project in this course, based on educational robotics and educational cooperation, with the intention to form a group of students and a teacher to make a robot involving chemical knowledge in civil construction. The group made a robot, using an Arduino kit and material recycling, to identify electrochemical corrosion in concrete structures. We conducted a case study about the group through the analysis of gestures, products made, and notes in a notebook, from which two cooperative categories emerged: planning and application. From these categories, we identified that the students had their cognitive structures unbalanced by difficult situations, trials, errors, and diverse knowledge. The formation of a new equilibrium condition resulted from individual and social developments in constant interdependence, allowing the joint construction of knowledge, whose complexity increased during the process and culminated in the realization of the robot. All these aspects characterized cooperative learning.
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    Classical food quality atributes and the metabolic profile of Cambuci, a native Brazilian Atlantic rainforest fruit
    (2021-06-12) Spricigo, Poliana Cristina; Correia, Banny Silva Barbosa; Borba, Karla Rodrigues; Taver, Isabela Barroso; Machado, Guilherme de Oliveira; Wilhelms, Renan Ziemann; Queiroz Júnior, Luiz Henrique Keng; Jacomino, Angelo Pedro; Colnago, Luiz Alberto
    The cambuci is a native Brazilian fruit from the Atlantic Forest biome. A soft and astringent pulp, a green color, and a sweet aroma are its main characteristics. Classical food quality attributes (fresh fruit mass, fruit height, diameters, total soluble solid, titratable acidity, and ratio) and the metabolic profile from ten accessions from three different locations were analyzed herein by analytical methods (refractometry and neutralization titration) and nuclear magnetic resonance spectroscopy. Concerning sugar content, sucrose was the predominant compound, with glucose and fructose alternating in second, depending on the accession. Citric acid was the most relevant acid, followed by shikimic and quinic acids in quite variable amounts. These three main acids vary in amounts for each accession. Ascorbic acid content emerges as an important quality attribute and makes this fruit nutritionally attractive, due to values comparable to those contained in citric fruits. The main amino acids identified in cambuci were glutamic acid individually or in comprising the tripeptide glutathione (glutamic acid, cysteine, glycine). The quality diversity of the evaluated accessions suggests the potentiality of cambuci use in future breeding programs.
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    Unequivocal structural assignments of three cardanol derivatives: an experimental and theoretical approach
    (2019) Barbosa, Layla Rosario; Souza, Daiane Santana; Queiroz Júnior, Luiz Henrique Keng; Cunha Neto, Alvaro; Lima, Dênis Pires de; Beatriz, Adilson; Romão, Wanderson; Castro, Eustaquio Vinicius Ribeiro de; Lacerda Júnior, Valdemar
    Cardanol was obtained by vacuum distillation of ‘‘cashew nut shell liquid’’ (CNSL). Cardanol is a by-product of cashew production and a building block for chemical synthesis; cardanol and its derivatives can be used for different types of applications. Three of these compounds are the subject of the present NMR study and theoretical comparison. 1H and 13C NMR signals were assigned using 1D and 2D NMR experiments. The DFT/B3LYP method using the cc-pVTZ basis set was employed for the calculations of the 1H and 13C NMR chemical shifts (δ). The obtained data were used as an auxiliary tool for unequivocal assignment of all 1H and 1³C NMR signals. For these compounds, the adopted theoretical model was sufficient to obtain a good description of the chemical shifts.
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    Colaboração educativa: uma proposta metodológica para ensino e pesquisa baseados na robótica pedagógica, epistemologia genética e educação libertadora
    (2022) Pinheiro, Ricardo Silverio Gomes; Soares, Márlon Herbert Flora Barbosa
    This paper discusses different meanings of collaboration and cooperation based on Piagetian and Freirean concepts among others. We also present a proposal for resignification of these terms in education, which resulted in two processes: educational collaboration and educational cooperation. By combining educational collaboration with pedagogical robotics, university students and a professor started with the context of civil construction to design a robot that was able to identify electrochemical corrosion in concrete structures. Two categories emerged from this process (questions and suggestions) and were analyzed in their form and content through a scientific research method proposed in three stages, based on educational collaboration: hierarchical ratio, categorical ratio and subcategorical qualitative analysis. The educational collaboration culminated in collaborative learning and proved to be a contextualized teaching method in which there is active student participation. Collaborative learning was evidenced by joint construction of knowledge to construct the robot, a result of the rebalance between individual and social factors.
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    Construindo conhecimento sobre a biologia evolutiva no ensino médio: a operação, a assimilação e a interação lúdica em um jogo pedagógico
    (2022-04) Moraes, Fernando Aparecido de; Soares, Márlon Herbert Flora Barbosa
    This article presents someresults of a doctoral thesis on the relationship between the experiences of the researcher, as a teacher, with what the specific literature in the area of Biology Teaching points out about the needs of teaching Biological Evolution in Basic Education. Thepurpose of this study was to provide theoretical support for thinking about possibilities for building knowledge of concepts related to Biological Evolution in the classroom based on the use of a playful pedagogical strategy, a pedagogical game. Initially, the study presented a theoretical discussion on aspects of teaching Biological Evolution in Basic Education, relating this teaching to the need for innovation in terms of strategies. Then, the theoretical discussion characterized the pedagogical game relating it to Piaget's Genetic Epistemology. After a brief theoretical discussion, we presented the methodological procedures of the qualitative research carried out with 21 volunteer students, from two classes of the 3rd grade of High School of a Full Time Education Center, located in the municipality of Jataí, state of Goiás. The analysis took place from the content constructed during the application of the game to students, recorded through audio-visual recording and later transcribed. In order to evaluatethe game, seeking to verify possibilities of allowing the construction of knowledge of evolutionary concepts, three categories that emerged in the pre-content analysis were brought to discussion: operation, assimilation and playful interaction. Throughoutthe analysis, at various moments in the application of the game, situations of operation, assimilation and playful interaction were observed. In these moments, it was also evident that abstract evolutionary concepts selected for the game, such as common ancestor and speciation, were collectively operated and assimilated by the students.At the end, based on the results achieved, the authors reflect on the importance of the pedagogical game, above all, in the teaching and learning process of Biological Evolution in Basic Education.
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    Improving quantitative 13C NMR performance by an adiabatic scheme
    (2018) Wollinger, Wagner; Fernandes, Jane Luíza Nogueira; Queiroz Júnior, Luiz Henrique Keng; Garrido, Bruno Carius; Aquino Neto, Francisco Radler de
    NMR is a primary method of measurement that provides quantitative traceable results without the need for a standard of the same measurand. Despite the advantages of the 1H nucleus, such as high sensitivity, short relaxation times and widespread distribution in organic compounds, some molecules present only labile H atoms, or the 1H peaks of a sample may overlap with impurities. With the CHORAD scheme – a combination of the pulse sequence CHORUS and adiabatic modulation for 1H decoupling – this study has shown that 13C NMR can be used for quantitative analyses with a bias smaller than 2% and expanded uncertainty of 0.7% (for a confidence level of 95%). Since 13C is found with significant non-statistic isotope fractionation, all the peaks of the sample and internal standard should be integrated and their bulk 13C abundances obtained by isotope ratio mass spectrometry (IRMS) must be considered to meet quantitative requirements. Future experimental work may be performed to test this procedure for complex matrix samples. This approach also proved to be suitable for studies of site-specific 13C distribution and led to better heteronuclear decoupling when compared with the use of adiabatic decoupling with ordinary hard 90° pulses, a combination extensively reported in the literature over the last decade. An examination of the molecules studied in this work and others from the literature revealed an overall trend in the 13C intramolecular profile – hydrogen-containing positions are often 13C-depleted. A potential contribution of 1JCH coupling to these results is discussed.
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    Chemical investigation and anatomical aspects of wood residues from Hymenaea courbaril L, Platymiscium ulei Harms, Hymenolobium petraeum Ducke
    (2022) Lima, Jennifer Araújo de Oliveira; Hayasida, Willian; Garcia, Mauro Galucio; Freitas, Jorge Alves de; Nascimento, Claudete Catanhede do; Queiroz Júnior, Luiz Henrique Keng; Lima, Maria da Paz
    In recent years, the interest in the propagation of native forest species has intensified with the aim of recovering degraded areas and the restoration of the landscape. As such, some species of Fabaceaeare considered promising woody species for planting in reforestation programs and agroforestry systems. In the present paper, the authors complement the need for studies related to secondary metabolites of the woody speciesHymenaea courbaril L. Platymiscium ulei Harms and Hymenolobium petraeum Ducke. Thus, the phytochemical study of H. courbaril led to the isolation and identification of diterpenes eperuic acid (1) and methyl eperuate (2); triterpenes oleanolic acid (3) andhederagenin(8); flavonoides quercetin (4), fisetinediol (5), liquiritigenin (6) and 3-methoxy-5,7,3',5'-tetrahydroxyflavanonol (7).P. ulei gave pterocarpane homopterocarpin (9) and coumarin scoparone(10); H. petraeum gave isoflavan sativan (11), in addition to the amino acidtyrosine(12). Flavonoids were the predominant constituents in the three species of Fabaceae; however, the presence of isoflavonoids in Platymiscium ulei and Hymenolobium petraeum is probably associated with the resistance of this high density wood to pathogenic fungi.
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    Possíveis relações dos conteúdos de química, física e biologia com os poderes das super-heroínas
    (2022-02) Pinto, Pollyana de Godoy; Soares, Márlon Herbert Flora Barbosa
    The increase in the presence of superheroines in many current movies and comics can contribute with the rise of women protagonism in many daily distinct situations with the objective of decrease gender prejudice. This work aimed for answering which high-school scientific contents might be related with super heroines’ powers presented in movies and comics. Research was developed in a public school of the metropolitan region of Goiânia – GO, with 122 students of the three high school grades. Students were evaluated and assigned three levels of connection between scientific concepts and superheroines’ powers. In Level 1, concepts were considered inappropriate, showing no satisfactory relations with superheroines’ powers. In Level 2, the conceptions and the relations were intermediary, but not deepened. In Level 3, the concepts were pertinent and satisfactory in what refers to the relation between science and the superheroines’ powers.
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    Electrochemical NMR spectroscopy: electrode construction and magnetic sample stirring
    (2019) Vianna, Pollyana Ferreira da Silva; Gomes, Bruna Ferreira; Lobo, Carlos Manuel Silva; Queiroz Júnior, Luiz Henrique Keng; Danieli, Ernesto Pablo; Blümich, Bernhard P.; Colnago, Luiz Alberto
    The use of nuclear magnetic resonance (NMR) spectroscopy to study electrochemical reactions in situ (EC-NMR), in solution, was demonstrated more than four decades ago. Although, the immense potential of EC-NMR has been demonstrated in several applications, this method has been limited to a few specialized groups since there are no commercial EC-NMR cells or cells that can be easily assembled for routine measurements. In most of the proposed EC-NMR cells the electrodes are placed inside the NMR coil, which deteriorates the magnetic field homogeneity and reduces the signal-to-noise ratio. To minimize these interferences, electrochemical cells have been constructed as flow cells, using ultra thin metallic films as electrodes, which are too complex to be produced by non-experts, or use non-metallic electrodes that have limited electrochemical applications. In this paper we report a very simple and efficient way to construct an EC-NMR cell using standard Pt and Ag wires as electrodes. These wires are assembled as coils on capillaries and are inserted into 5 mm NMR tubes and placed approximately 0.5 mm above the NMR coil. During the in situ EC-NMR reaction the magnetohydrodynamic effect stirs the solution, homogenizing the concentration of the reagent and the product in the NMR detection region. This effect allows the concentration of the analyte to be measured in real time, even with the electrodes outside the NMR detection region. The electrode materials are not limited to Pt or Ag wires and can be replaced by other materials according to the studied reaction. Details showing how to make the electrodes are presented in a video in the supplementary material. The application and performance of this cell were demonstrated with an in situ EC-NMR study of the electro-oxidation of ascorbic acid in solution. In this particular case the magnetic field increased the reaction rate by a factor of approximately two.
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    Determination of physicochemical properties of biodiesel and blends using low-field NMR and multivariate calibration
    (2019) Constantino, André Fazolo; Cubides Roman, Diana Catalina; Santos, Reginaldo Bezerra dos; Queiroz Júnior, Luiz Henrique Keng; Colnago, Luiz Alberto; Cunha Neto, Alvaro; Barbosa, Lúcio Leonel; Romão, Wanderson; Castro, Eustaquio Vinicius Ribeiro de; Filgueiras, Paulo Roberto; Lacerda Júnior, Valdemar
    Because the methods specified by regulatory agencies for the determination of the physicochemical properties of biodiesel can be laborious and expensive, the development of alternative methodologies represents a major breakthrough. Thus, low-field nuclear magnetic resonance (NMR) is an advantageous option because it is nondestructive and reduces the cost and time consumption. In this study, the partial least squares (PLS) regression method was used to create models that correlated the decay curves of the Carr–Purcell–Meiboom–Gill (CPMG) signal, obtained from low-field NMR equipment (2.2 MHz for 1H), with the kinematic viscosity, specific mass and refractive index of biodiesel and their blends. Seventeen oilseeds diversified between edible and non-edible oils were utilized to synthesize the biodiesel and produce binary blends. Separately, multivariate calibration models were created only with biodiesel and blends with castor bean because these samples showed different tendencies from the others. The values of root mean square error of prediction (RMSEP) for the kinematic viscosity, specific mass and refractive index were equal to 0.1 mm2·s−1, 3.7 kg·m−3 and 0.002, respectively, for samples of biodiesel and blends without castor bean and 0.6 mm2·s−1, 2.0 kg·m−3 and 0.0005 for samples of biodiesel and blends with castor bean. The results reveal that the developed models are very satisfactory to predict the quality parameters of biodiesel and blends based on CPMG data with fairly good efficacy.
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    Using TD-NMR relaxometry to assess the effects of diet type and stocking rate on the incidence and degree of severity of myopathies in broilers
    (2022) Cônsolo, Nara Regina Brandão; Barbosa, Luís Carlos Garibaldi Simon; Moraes, Tiago Bueno de; Buarque, Vicente Luiz Macêdo; Colnago, Luiz Alberto; Queiroz Júnior, Luiz Henrique Keng; Oliveira, Vitor Mendes de; Hannaford, Rina; Araújo, Cristiane Soares da Silva; Roque, Fabricia de Arruda; Granghelli, Carlos Alexandre; Fonseca, André Camêlo; Araújo, Lúcio Francelino
    This study aimed to evaluate different feeding strategies and stocking rates (SR) on the occurrence and severity of broiler myopathies. Additionally, a second aim was to test the potential use of Time-Domain Nuclear Magnetic Resonance (TD-NMR) relaxometry for assessing white striping (WS) and wooden breast (WB) incidence and the degree of severity in broiler chicken breasts. Treatments were arranged in a 2 × 2 factorial design and consisted of two nutritional levels (regular and superior diets) and two different SR (high 47 kg/m2 or regular 59 kg/m2). Infrared thermography (IRT) images were recorded on three different days to determine the average, minimum and maximum temperatures. After 49 days of rearing, birds were slaughtered, and 75 breasts were weighed and classified according to the absence (normal breast, without the occurrence of myopathy – NB) or occurrence and severity of WB and WS. The whole breasts were analysed by TD-NMR relaxometry using the Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence and Continuous Wave-Free Precession (CWFP-T1) pulse sequence. There was no effect of diet and diet*SR interaction on the weight of breast meat; however, chickens raised at the higher density presented a lower breast weight (P < 0.0001; 490 vs. 539 g). The incidence and severity of myopathies was not influenced by the treatments (P = 0.9467); the frequencies of WB and WS were similar in the different treatments. For CPMG and CWFP-T1, three and two relaxation populations were noted, respectively. The sPLS-DA model optimisation showed a significant separation between WS and NB in terms of occurrence and severity. In conclusion, changes in diet and SR did not mitigate the occurrence or severity of WS and WB. Additionally, TD-NMR relaxometry showed to be a promising technology for evaluating and segregating breasts according to myopathy incidence and severity.
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    Achachairú (Garcinia humilis): chemical characterization, antioxidant activity and mineral profile
    (2019) Tomé, Alessandra Cristina; Mársico, Eliane Teixeira; Silva , Flavio Alves da; Kato, Lucilia; Nascimento, Talita Pimenta do; Monteiro, Maria Lúcia Guerra
    The present study characterized the nutritional value, including the total phenolic compounds, antioxidant potential, and mineral profile of peel, pulp, and seed of achachairú fruit. Fruits were collected and selected for appearance, ripeness stage, absence of physical damage, and then sanitized and pulped (when fruit peel, pulp, and seed were separated). These parts were lyophilized separately to guarantee the analytical results. The results indicated high moisture content in the fruit peel (79.63%), and pulp (80.68%). Potassium was the most abundant mineral found in fruit seed (224.56 mg/100 g), followed by peel (146.32 mg/100 g), and pulp (46.32 mg/100 g), while the least abundant element was copper (peel = 0.03 mg/100 g, pulp = 0.01 mg/100 g, and seed = 0.04 mg/100 g) with no significant difference between fractions. An influence of solvent used for determination of antioxidant activity of achachairú fruit was observed, in which ethanolic extract was regarded as the best solvent for this test in all evaluated methods. Evaluation of phenolic compounds showed variable results, where the highest contents (p < 0.05) were found in aqueous extract from the peel (149.71 mg EAG/100 g), and ethereal extract from the seed (212.28 mg EAG/100 g). The highest tannin content (p < 0.05) was found in seeds, both for condensates (63.83 mg de CAE/g) and hydrolysates (11.84 mg GA/g), and there was no significant difference between results from fruit peel and pulp.
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    Brazilian insulin plant as a bifunctional food: dual high-resolution PTP1B and α-glucosidase inhibition profiling combined with HPLC-HRMS-SPE-NMR for identification of antidiabetic compounds in Myrcia rubella Cambess
    (2018) Lima, Rita de Cássia Lemos; Kato, Lucilia; Kongstad, Kenneth Thermann; Staerk, Dan
    Six species of Myrcia, commonly known as 'insulin plants' in Brazil, were assessed for their potential as functional foods. Thus, dual high-resolution α-glucosidase/PTP1B inhibition profiling and HPLC-HRMS-SPE-NMR analysis were used to identify the antidiabetic constituents of the crude ethyl acetate extract of M. rubella Cambess. A total of 31 compounds were identified, including seven α-glucosidase inhibitors with IC50 values between 0.6 and 22.4 μM: 4,5-dicaffeoylquinic acid, isoquercitrin, quercetin-3-O-β-d-glucuronide, kaempferol-3-O-(6″-galloyl)-β-d-glucopyranoside, quercetin-3-O-(6″-malonyl)-glucopyranoside, quercetin-3-O-(6″-(E)-feruloyl)-β-d-glucopyranoside, and quercetin-3-O-(2″-(E)-sinapoyl)-glucopyranoside as well as three strong PTP1B inhibitors with IC50 values between 0.4 and 3.1 μM: kaempferol-3-O-α-l-rhamnoside, astragalin, and arjunolic acid. These results show that M. rubella is a potential bifunctional food for management of type 2 diabetes.