Abstract Plasticulture improves crop quality and yield through polymeric films, but their improper disposal harms the environment due to humidity and contamination. This study aimed to develop biodegradable mulch films using soybean and peanut hulls and poly (butylene-adipate-co-terephthalate) (PBAT). The residues were characterized by thermogravimetric analysis and mulch films were evaluated by water absorption, contact angle and mechanical properties. The thermal behavior of the residues indicated stability below 200ºC. The agro-waste improved hydrophobicity but increased the water absorption values of the films by up to 18.5x (PBAT/SH5 after 14 days). Micrographs obtained by scanning electron microscopy indicated an important distribution of residue particles and formation of agglomerates, leading to lower mechanical performance. The study found that agro-industrial residues in powder form can be added to the polymeric matrix to produce biodegradable mulch films through traditional processing techniques. This approach has the potential to contribute to a more sustainable production system.

Abstract In this study, green high-density polyethylene (GHDPE) composites with 5, 10 and 15% natural powdered cork (CP) with and without 5% maleic anhydride (PE-g-MA) were developed in order to evaluate the potential of these materials for civil construction applications. The composites were produced in a co-rotating twin-screw extruder and injection molded. An impedance tube was used to determine the acoustic behavior of the composites, which were then used as ceiling tiles in prototypes of provisional constructions in order to study ascertain their performance with respect to thermal comfort in the City of Teresina, PI - Brazil. Our data indicates that composites sound absorption coefficient values are good between 500 and 1200 Hz, especially for those with a higher percentage of cork, with the lowest absorption rate observed for composites containing PE-g-MA. The composites used in the prototypes provided a decrease in the internal temperature of the built structure.

The present work investigates the aquatic biodegradation of poly(3-hydroxybutyrate) (PHB)/nanoclay bionanocomposites containing PP-g-MA as compatibilizing agent. Both pristine and organically modified (Cloisite20A®) montmorillonite clay were used as fillers in different content (1 and 3 wt%). The bionanocomposites were prepared by melt intercalation in a single screw extruder. There after films (50x50x0.5mm) were prepared by compression and assessed by X-ray diffraction. Aquatic biodegradation of the films was appraised by visual inspection, optical microscopy, counting and identification of bacteria. Results proposed that the water of the Parnaíba River in the city of Teresina (Piauí, Brazil) has microorganisms (Pseudomonas putida and Pseudomonas aeruginosa) capable of degrading these bionanocomposite films, particularly the films with 3 wt% organoclay. Our data indicated the bacteria Pseudomonas aeruginosa degraded dexterously all the films. This work collaborates with the preservation of the environment and expands the use of bionanocomposites in expendable items with the development of films with properties favorable to biodegradation in aquatic environments. It is believed that PHB/clay/PP-g-MA films emerge as a promising alternative for the packaging industry.

SUMMARY Maturity-onset diabetes of the young (MODY) is a heterogeneous group of monogenic forms of diabetes mellitus with distinct clinical features. Clinical dermatological phenotypes in MODY patients are very rare in literature. This report describes a patient with HNF1A-MODY presenting with necrobiosis lipoidica (NL) and granuloma annulare (GA). A 39-year-old asymptomatic woman, with atypical diabetes diagnosed at age 17, has a confirmed HNF1A mutation on exon 2 (c.392G>A, p.R131Q), classified as Pathogenic by the ACMG guidelines. She has reasonable metabolic control using oral anti-diabetic medications and has no chronic diabetic complications. Clinical and histologic diagnoses of both NL and GA were made. We discuss these conditions and their association with MODY.

This work developed ternary films based on Poly(Lactic Acid) (PLA), Cloisite 30B (C30B) and Oregano Essential Oil (OEO) as proposal to be applied in food packaging. The films thus manufactured were unscathed, with reduced surface defects. Their thickness and moisture content varied according to the composition and content of each component in the formulation. Optical micrographs indicated a homogeneous morphology, with good distribution of clay in the matrix. FTIR data confirms the incorporation of OEO into the films. TGA analysis indicated that the thermal stability of the films was not significantly affected by the incorporation of C30B and OEO. OEO incorporation did not promote an efficient antimicrobial action which is probably due to its retention by the clay. Further studies are needed to confirm this hypothesis. The combination between C30B and OEO in the PLA polymeric matrix is a promising proposal.

RESUMO Com o agravamento dos problemas ambientas causados pela má gestão de resíduos sólidos, os polímeros biodegradáveis surgem como alternativas de materiais sustentáveis que podem de minimizar o impacto ambiental. Diante da demanda urgente por produtos sustentáveis, o presente trabalho teve como objetivo desenvolver filmes a base poli (ácido láctico) (PLA) e a proteína isolada de soja (SPI) via extrusão plana para estudo como potencial aplicação em embalagens para alimentos. Os filmes foram produzidos em cinco diferentes formulações: a matriz pura de PLA como filme controle; PLA com 3 e 5% da proteína isolada de soja, PLA com 3 e 5% da proteína isolada de soja com o acréscimo de 1,5% de glicerol, e analisados via termogravimetria, espectroscopia de infravermelho, transmitância por UV-vis e ângulo de contato. O resultados indicaram que a inserção dos componentes à matriz de PLA levou a redução da estabilidade térmica dos filmes, que também não apresentaram interação química entre os seus componentes. As partículas de soja, melhor dispersas na matriz em função da presença do plastificantes, auxiliaram na redução da transmitância dos filmes, e na formação de sistemas hidrofílicos.

ABSTRACT With the worsening of environmental problems caused by poor solid waste management, biodegradable polymers emerge as alternatives for sustainable materials that can minimize environmental impact. In view of the urgent demand for sustainable products, this study aimed to develop films based on poly (lactic acid) (PLA) and isolated soy protein (SPI) via flat extrusion for study as a potential application in food packaging. The films were produced in five different formulations: the pure PLA matrix as a control film; PLA with 3 and 5% of the isolated soy protein, PLA with 3 and 5% of the isolated soy protein with the addition of 1.5% glycerol, and analyzed via thermogravimetry, infrared spectroscopy, UV-vis transmittance and angle contact. The results indicated that the insertion of the components in the PLA matrix led to a reduction in the thermal stability of the films, which also did not show chemical interaction between their components. The soy particles, better dispersed in the matrix due to the presence of plasticizers, helped in reducing the transmittance of the films, and in the formation of hydrophilic systems.

Abstract In this work, nanocomposites were developed and evaluated using high-density bio polyethylene (BPEAD)/Cloisite 20A (3 and 6%)/commercial antimicrobial additive (0,5 and 1%) containing 1% of zinc pyrithione dispersed in vinyl acetate (EVA). The samples were prepared in a single screw extruder using the melt intercalation technique and then by flat extrusion to obtain the films. X-ray diffraction (XRD) showed an increase in basal spacing and exfoliation of the structure of some films. The Fourier Transform Infrared Spectroscopy (FTIR) analysis illustrated the main functional groups for BHDPE and EVA. Thermal analysis indicated that BHDPE degradation did not change with organoclay addition, but crystallinity increased. The mechanical properties showed an increase in the elastic modulus and a decrease in maximum tensile strength. This work contributes to the development and improvement of the natural properties of BHDPE in order to enlarge its applications.

Resumo Compósitos de polietileno verde e argila vermiculita foram desenvolvidos por meio da técnica de intercalação por fusão com o objetivo de investigar seu potencial uso como material de construção. Os compósitos foram processados em uma extrusora monorosca e moldados em uma termoprensa hidráulica. Para este trabalho, foram analisadas a resistência à propagação de chamas e os efeitos do envelhecimento natural do polietileno verde e seus compósitos. Amostras foram expostas a um ensaio de degradação abiótica durante 90 dias como forma de avaliar os efeitos das condições climáticas na morfologia e nas propriedades mecânicas do material. O teste de inflamabilidade evidenciou o efeito catalítico da argila, uma vez que para todos os compósitos avaliados, a resistência à propagação de chamas foi inferior em relação ao polímero verde puro. Os efeitos do envelhecimento natural na morfologia dos materiais foram caracterizados pela transição da matriz polimérica de um aspecto dúctil para uma aparência mais frágil e o aparecimento de vazios e de fraturas internas. Em virtude disso, o desempenho mecânico dos sistemas foi diretamente afetado, como resultado de diversos tipos de degradação abiótica sofrida pelas amostras.

Abstract Green polyethylene and vermiculite clay composites were developed through the fusion intercalation technique with the aim of investigating their potential use as a building material. The composites were processed in a single screw extruder and molded in a hydraulic thermopress. For the purpose of this study, flame propagation resistance and the natural aging effects of green polyethylene and its composites were analyzed. The samples were exposed to the abiotic degradation test for 90 days with the aim of assessing the effects of climate conditions on the material’s morphology and mechanical properties. The flammability test demonstrated the catalytic effect of the clay, since for all composites evaluated, the flame propagation resistance was inferior to that of the pure green polymer. The effects of natural aging on the morphology of the materials were characterized by the transition of the polymeric matrix from a ductile aspect to a more fragile appearance and the emergence of voids and internal fractures Hence, the mechanical performance of the systems was directly affected, as a result of several types of abiotic degradation suffered by the samples.

Abstract Polymer processing parameters may considerably affect final product characteristic as, if properly chosen, these parameters may lead to products with optimal properties. The aim of this work is to evaluate the rheological characteristics of poly(ethylene terephthalate) (PET) by torque rheometry, as well as to estimate its incipient degradation rate during processing in an internal laboratory mixer. In order to estimate the temperature coefficient of the viscosity (β), and the pseudoplasticity index (n) of PET, two sets of experiments need to be performed. In the first one, the polymer is processed at three different temperatures at a single rotor speed for 10 min, getting temperature coefficient of the viscosity equal to β = 0.053 °C-1. In the second set of experiments, the resin (PET) is processed at a single temperature at six different rotor speeds for the same time interval and the pseudoplasticity index was determined, n = 0.78. From the results obtained, it is possible to indicate the internal mixer as an equipment not only for mixing polymers or composites, but as a tool for determining important rheological variables for predicting degradative processes.

Abstract The use of polymer blends and composites based on fossil-based and bio-based polymers has become an important environmentally protective alternative for common use and disposable plastics applications such as packaging, bottles and trays. The disposal of these more degradable products, however, may also harm the environment and, therefore, recycling these systems becomes relevant. Recycling involves reprocessing which can significantly change the morphology and properties of polymeric products. Therefore, this study deals with the effects of reprocessing cycles on the properties and morphology of blends and nanocomposites based on fossil and bio-based polymers. The systems investigated were: a) neat polypropylene (PP), b) a polypropylene/poly(3-hydroxybutyrate) (PP/PHB) blend and c) PP/PHB/organoclay nanocomposite compatibilized with polypropylene-g-maleic anhydride (PP-g-MA) and erucamide. These materials were submitted to up to seven extrusion cycles in a single screw extruder operating at 60 rpm. Samples were taken after the first, third, fifth and seventh extrusion cycles and their tensile properties and morphology were determined. Scanning electron microscopy indicated that two phases were observed in the blend which showed spherical PHB domains. The addition of clay, PP-g-MA and erucamide improved the adhesion between the nanocomposites components. X-ray diffraction analysis showed that crystallinity tended to increase with the number of reprocessing cycles for all systems investigated up to the fifth cycle and then tended to decrease. A 10% crystallinity increase was observed for neat PP in the fifth cycle. In general, the tensile properties of all systems decreased with reprocessing and the highest losses were observed for the PP/PHB blend after seven processing cycles with 50% and 37% decreases in stress at break and elastic modulus, respectively. Impact strength of the PP matrix and of the PP/PHB blend tended to decrease with reprocessing, except for the nanocomposite which showed a slight increase especially after the seventh processing cycle in which an 18% increase in impact strength was observed.

Resumo Objetivo analisar a autopercepção de saúde e da qualidade de vida associados aos fatores contextuais em idosos não institucionalizados em município rural no interior do Brasil. Método Estudo transversal de base populacional. Foram incluídos indivíduos com 60 anos ou mais, não institucionalizados, residentes em município com características rurais. Foram utilizadas variáveis sociodemográficas, autopercepção da saúde e da qualidade de vida, nível de atividade física e desempenho funcional. Os dados foram coletados em domicílio com aplicação de entrevista e dos instrumentos: WHOQOL BREF, Questionário Internacional de Atividade Física (IPAQ) e teste Timed Up and Go (TUG). Para a análise de comparação e associação foram aplicados os testes qui-quadrado ou exato de Fisher e Razão de Prevalência (RP) e intervalos de confiança (IC). Resultados Participaram do estudo 142 idosos, sendo 58,5% do sexo feminino, com média de idade de 72,4 (±8,0) anos. A autopercepção da saúde foi associada à prática de atividade física (RP=1,13, IC=1,01-1,27) e ao desempenho funcional (RP=1,24, IC=1,03-1,48). A percepção da saúde (RP=1,66, IC=1,57-1,76) e qualidade de vida (RP=1,70, IC=1,60-1,79) boa/muito boa foi associada de forma positiva à prática de atividade física e independência funcional. Conclusão A prática de atividade física e a manutenção da independência funcional contribuem de forma significativa para uma percepção positiva da saúde e qualidade de vida. Porém, idosos insuficientemente ativos e independentes também podem ter boa percepção da saúde. Recomendam-se intervenções nas políticas públicas que considerem características intrínsecas de cada população visando manter ou melhorar a percepção de saúde e qualidade de vida dos idosos.

Abstract Objective to analyze self-perception of health and quality of life associated with contextual factors in non-institutionalized older adults people in a rural municipality in the interior of Brazil. Method Cross-sectional population-based study. Individuals aged 60 years or more, not institutionalized, living in a municipality with rural characteristics were included. Sociodemographic variables, self-perceived health and quality of life, level of physical activity and functional performance were used. Data were collected at home with application of interviews and instruments: WHOQOL BREF, International Physical Activity Questionnaire (IPAQ) and Timed Up and Go test (TUG). For the comparison and association analysis, the chi-square or Fisher’s exact test and the Prevalence Ratio (PR) and confidence intervals (CI) were applied. Results The study involved 142 older adults, 58.5% female, with a mean age of 72.4 (±8.0) years. Self-perceived health was associated with the practice of physical activity (PR=1.13, CI=1.01-1.27) and with functional performance (PR=1.24, CI=1.03 -1.48). The perception of good/very good health (PR=1.66, CI=1.57-1.76) and quality of life (PR=1.70, CI=1.60-1.79) was associated with positive to the practice of physical activity and functional independence. Conclusion The practice of physical activity and maintenance of functional independence significantly contribute to a positive perception of health and quality of life. However, elderly people who are insufficiently active and independent may also have a good perception of health. Interventions in public policies that consider the intrinsic characteristics of each population are recommended, aiming to maintain or improve the perception of health and quality of life of the elderly.

A discussão sobre as repercussões das relações de gênero na vida das mulheres foi temática de uma atividade teórico-prática sobre técnicas e métodos de pesquisa nas Ciências Sociais de uma disciplina de pós-graduação em Saúde Coletiva. Adotou-se, como referencial teórico, a perspectiva de gênero como decorrente do posicionamento socio-histórico, no qual a experiência de ser mulher se constrói. O trabalho tem como objetivo relatar a experiência de execução dessa atividade como parte da trajetória acadêmica das mestrandas envolvidas. Por meio da articulação entre teoria e prática, pôde-se vivenciar o passo a passo da escolha, da elaboração e da descrição metodológica na produção do trabalho. O exercício de reflexividade esteve presente, localizando as estudantes diante do seu objeto de investigação. A atividade permitiu imersão na temática e reconhecimento do seu caráter político, histórico e social como agente de consolidação ou reformulação das práticas vigentes.

The discussion surrounding the impact of gender relations on the life of women was the theme of a theoretical and practical activity on social science research techniques and methods as part of a module of a master’s degree in public health. We adopted the gender perspective, drawing on the social and historical positioning of gender relations to construct the experience of being a woman. This article recounts the development of this activity as part of the academic trajectory of the master’s students involved. Through the articulation between theory and practice, it was possible to experience the different steps of the choice, elaboration and description of the methodology in the production of the work. Reflexivity was present, situating the students before the object of investigation. The activity enabled the students to immerse themselves in the topic and recognize its political, historic and social natures as an agent of the consolidation or reformulation of current practices.

La discusión sobre las repercusiones de las relaciones de género en la vida de las mujeres fue la temática de una actividad teórico-práctica sobre técnicas y métodos de investigación en las ciencias sociales de una asignatura de postgrado en salud colectiva. Se adoptó como referencial teórico la perspectiva de género como proveniente del posicionamiento sociohistórico, en el cual se construye la experiencia de ser mujer. El objetivo del trabajo es relatar la experiencia de realización de esa actividad como parte de la trayectoria académica de las alumnas de maestría involucradas. Por medio de la articulación entre teoría y práctica es posible vivir el paso a paso de la elección, elaboración y descripción metodológica en la producción del trabajo. Estuvo presente el ejercicio de reflexividad, localizando a las alumnas ante su objeto de investigación. La actividad permitió una inmersión en la temática y reconocimiento de su carácter político, histórico y social como agente de consolidación o reformulación de las prácticas vigentes.

A discussão sobre as repercussões das relações de gênero na vida das mulheres foi temática de uma atividade teórico-prática sobre técnicas e métodos de pesquisa nas Ciências Sociais de uma disciplina de pós-graduação em Saúde Coletiva. Adotou-se, como referencial teórico, a perspectiva de gênero como decorrente do posicionamento socio-histórico, no qual a experiência de ser mulher se constrói. O trabalho tem como objetivo relatar a experiência de execução dessa atividade como parte da trajetória acadêmica das mestrandas envolvidas. Por meio da articulação entre teoria e prática, pôde-se vivenciar o passo a passo da escolha, da elaboração e da descrição metodológica na produção do trabalho. O exercício de reflexividade esteve presente, localizando as estudantes diante do seu objeto de investigação. A atividade permitiu imersão na temática e reconhecimento do seu caráter político, histórico e social como agente de consolidação ou reformulação das práticas vigentes.

The discussion surrounding the impact of gender relations on the life of women was the theme of a theoretical and practical activity on social science research techniques and methods as part of a module of a master’s degree in public health. We adopted the gender perspective, drawing on the social and historical positioning of gender relations to construct the experience of being a woman. This article recounts the development of this activity as part of the academic trajectory of the master’s students involved. Through the articulation between theory and practice, it was possible to experience the different steps of the choice, elaboration and description of the methodology in the production of the work. Reflexivity was present, situating the students before the object of investigation. The activity enabled the students to immerse themselves in the topic and recognize its political, historic and social natures as an agent of the consolidation or reformulation of current practices.

La discusión sobre las repercusiones de las relaciones de género en la vida de las mujeres fue la temática de una actividad teórico-práctica sobre técnicas y métodos de investigación en las ciencias sociales de una asignatura de postgrado en salud colectiva. Se adoptó como referencial teórico la perspectiva de género como proveniente del posicionamiento sociohistórico, en el cual se construye la experiencia de ser mujer. El objetivo del trabajo es relatar la experiencia de realización de esa actividad como parte de la trayectoria académica de las alumnas de maestría involucradas. Por medio de la articulación entre teoría y práctica es posible vivir el paso a paso de la elección, elaboración y descripción metodológica en la producción del trabajo. Estuvo presente el ejercicio de reflexividad, localizando a las alumnas ante su objeto de investigación. La actividad permitió una inmersión en la temática y reconocimiento de su carácter político, histórico y social como agente de consolidación o reformulación de las prácticas vigentes.

Abstract This study aims to evaluate the effects of natural weathering in the city of Teresina, State of Piauí, Brazil, on the morphology and mechanical properties of eco-composites based on high-density green polyethylene, powdered cork and compatibilizer processed in a twin-screw extruder and injection molded. The analyses revealed that although weathering induced surface bleaching of eco-composites and cracking, these effects were not intense in the compatibilized samples. The tensile properties of the investigated materials were affected by abiotic degradation, which led to a reduction of the tensile strength and elastic deformation of the eco-composites, however, the incorporation of PEgMA was fundamental for the maintenance of mechanical performance after natural aging. In general, the results obtained were satisfactory for external applications of the compatibilized eco-composite with 15% cork in the proposed weathering range, which indicates its possible use in temporary constructions.