Abstract Changes in lifestyles and clothing consumption patterns as paths to a sustainable society defines sharing as one of the strategies of slow fashion. Through practice theories, this research explores materials, competences and meanings that make up the practice. Thus, we sought to identify how the elements and the dynamics of clothing sharing are configured. Using a qualitative case study, data were collected through observations, semi-structured interviews (individual and group), and a focus group carried out with practitioners and providers of a collaborative store. Our results revealed that: (a) for practitioners, the practice of sharing means exclusivity, economy, and sustainable consumption; (b) for providers, the practice is linked to a conscious consumption as an opportunity for more sustainable business, including financially (c) and different materials guide the practice of sharing clothes. The elements of clothing sharing are similar between practitioners and providers; therefore, they indicate the effectiveness of the practice, in addition to pursuing sustainable consumption. The research then contributes to the development of research on sustainable consumption once it identifies management practices aimed at the collaborative consumption of clothing.

Resumo As mudanças nos estilos de vida e nos padrões de consumo de roupas, que vêm sendo debatidas como caminhos para uma sociedade mais sustentável, definem o compartilhamento como uma das estratégias do slow fashion para promover o consumo consciente. Por meio das teorias da prática, esta pesquisa explora materiais, competências e significados que compõem a prática. Assim, buscou-se identificar como se configuram os elementos e a dinâmica do compartilhamento de roupas. Utilizando um estudo de caso qualitativo, os dados foram coletados por meio de observações, entrevistas semiestruturadas (individuais e em grupo) e grupo focal, realizados com praticantes (consumidores) e provedores (fornecedores) de uma loja colaborativa. Os resultados revelaram que: (a) para os praticantes, a prática do compartilhamento significa exclusividade, economia e consumo sustentável; (b) para os provedores, a prática está atrelada ao consumo consciente como oportunidade de negócios mais sustentáveis, inclusive financeiramente; e (c) diversos materiais orientam a prática do compartilhamento de roupas. Os elementos do compartilhamento de roupas são semelhantes entre praticantes e provedores, portanto indicam a eficácia da prática, além de buscar um consumo sustentável. A pesquisa, então, contribui para o desenvolvimento de pesquisas sobre consumo sustentável, uma vez que identifica práticas de gestão voltadas ao consumo colaborativo de vestuário.

Abstract Electrospun fibers find a number of biomedical applications, like scaffolds for tissue engineering, as polymer nanofiber mats can mimic the extracellular matrix (ECM) of the body. In this research, non-woven mats composed of poly(L-lactic acid) (PLLA) fibers were obtained by low voltage (6 kV) electrospinning of PLLA/chloroform (CL)/sodium lauryl ether sulfate (SLES) solution. Tests were performed in two different collector/capillary distances and the produced fibers were evaluated by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and cell viability. The results show the formation of three dimensional mats composed of porous fibers created by the addition of small amounts of aqueous solution of SLES surfactant; a higher crystallinity degree for longer collector/capillary electrospun distance and positive cell proliferation.

Resumen En nuestra revisión anterior (parte I - propiedades del material), se dis- cutieron las propiedades químicas, físicas y morfológicas, aplicaciones y mecanismos de obtención del poli (3-hidroxibutirato). El PHB es un polímero de base biológica que se presenta como una opción ecológica debido a su característica de degradación en la presencia de factores ambientales y debido a la acción de microorganismos como algas, hongos y bacterias. En esta segunda revisión se abordan aspectos relacionados con los tipos de degradación a los que este polímero está sujeto y las condiciones nece- sarias para su degradación. Entre estos mecanismos están la degradación térmica, la degradación termomecánica, la degradación abiótica, la foto de degradación y la biodegradación. Se percibe que la degradación del PHB puede ser vista como una característica ventajosa de este material. Esta revisión complementa la anterior y utiliza la misma terminología.

Abstract In our previous review (Part I - Material Properties), the chemical, physical and morphological properties, applications and mechanisms of obtaining poly (3-hydroxybutyrate) were discussed. PHB is a biologically based polymer that presents itself as an ecological option due to its characteristic degradation before environmental factors and due to the action of microorganisms such as algae, fungi and bacteria. In this second review, aspects related to the types of degradation to which this polymer is subjected and the necessary conditions for its degradation are addressed. Among these mechanisms are thermo-degradation, thermo-mechanical degradation, abiotic degradation, photo degradation and biodegradation. It is understood that the degradation of PHB can be seen as an advantageous feature of this material. This review complements the previous one and uses the same terminology.

RESUMO Este trabalho tem como objetivo a preparação de mantas compostas por fibras do polímero biodegradável poli(3-hidroxibutirato) -(PHB) por meio da técnica de eletrofiação. Obtiveram-se mantas sob diferentes condições, variando-se o fluxo, a temperatura da solução, a tensão aplicada e a adição de um agente surfactante. O material obtido foi analisado por microscopia eletrônica de varredura (MEV), calorimetria exploratória diferencial (DSC), termogravimetria (TG), difratometria de raios-X (DRX) e viabilidade celular. A caracterização por MEV mostrou que os melhores resultados, apresentando as fibras com diâmetros constantes de 0,77 µm e sem a formação de grãos, foram atingidos nas seguintes condições: concentração da solução de 10% (m/v) em CF/DMF (9/1), fluxo da solução de 5,8 ml/h, tensão de 17 kV e adição de surfactante (dodecilsulfato de sódio, SDS). Os resultados mostraram que as variações de vazão, tensão e a adição de surfactante não influenciam muito o diâmetro médio das fibras, enquanto o aumento da temperatura diminui este parâmetro. No entanto, a adição de um agente surfactante deixa a manta mais densa e com poros interconectados, além de permitir a proliferação celular, sendo então indicada para produção de mantas para uso como arcabouço.

ABSTRACT This work aims the preparing of mats composed of poly (3-hydroxybutyrate) -(PHB) biodegradable polymeric fibers, using the electrospinning technique. Mats were obtained under different conditions: changing the flow and temperature of the solution, tension and the addition of a surfactant to the solution. The obtained material was analyzed by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetry (TG), X ray diffractometry (XRD) and cell viability. The characterization by SEM showed that the best results, presenting fibers with constant diameters of 0.77 μm and without beads formation, were reached under the following conditions: concentration of 10% (m / v) solution in CF / DMF (9/1), solution flow of 5.8 ml/h, 17 kV and addition of surfactant (sodium dodecylsulfate, SDS). The results showed that the variation of the flow, tension and surfactant did not influence the average diameter of the fibers, but the increase of the temperature decreases this parameter. Moreover, the addition of a surfactant increases the density of the blankets and interconnect the pores, allowing cellular proliferation, and, thus. it is indicated for use as scaffolds.

Resumen Este artículo presenta una revisión de las características químicas, físicas y morfológicas, así como las aplicaciones y mecanismos existentes para la producción de poli(3-hidroxibutirato). Este biopolímero, que se obtiene a partir de fuentes renovables, se degrada cuando se expone en ambientes biológicamente activos y es biocompatible, es decir, no es rechazado por el cuerpo humano en aplicaciones de salud. Sin embargo, a pesar de pre- sentar propiedades similares con algunos plásticos convencionales, el PHB exhibe comportamiento frágil e inestabilidad térmica cuando se procesa. La literatura propone el uso de mezclas, el desarrollo de copolímeros o la inserción de aditivos en un intento por mejorar las propiedades mecánicas y térmicas del PHB.

Abstract This paper presents a review of the chemical, physical and morphological characteristics, as well as the existing applications and mechanisms for the production of poly (3-hydroxybutyrate). This biopolymer, which is obtained from renewable sources, degrades when exposed in biologically active environments and is biocompatible, that is, it is not rejected by the human body in health applications. However, in spite of presenting similar properties with some conventional plastics, the PHB exhibits fragile behavior and thermal instability when processed. The literature proposes the use of blends, the development of copolymers or the insertion of additives in an attempt to improve the mechanical and thermal properties of PHB.

Resumo Os dispositivos de fixação óssea, metálicos convencionais, usados em cirurgia crâniomaxilofacial têm apresentado alguns problemas, tais como, corrosão, inflamação e infecção, além de neoformação de estrutura óssea mecanicamente inferior devido à atrofia gerada pela diferença de módulo elástico entre metal e osso, razões que têm levado ao aumento do interesse por dispositivos poliméricos bioarreabsorvíveis. Os polímeros biorreabsorvíveis mais utilizados nesta aplicação pertencem à família dos poli (α-hidroxi ácidos), que têm como característica degradarem por hidrólise de suas ligações ésteres, tal como copolímero poli (L-ácido láctico-co-D, L ácido láctico), PLDLA. Neste trabalho foram investigados alguns efeitos da adição de poli (caprolactona triol), PCL-T sobre PLDLA. Foram preparados pinos por fusão de blendas nas seguintes composições 100/0, 90/10, 70/30 and 50/50 (m/m), PLDLA/PCL-T. Os pinos foram caracterizados por diferentes técnicas (DSC, MEV e ensaio mecânico). A degradação in vitro dos pinos foi investigada, sendo observado que a adição de PCL-T no PLDLA modificou suas propriedades mecânicas e morfológicas. Tais mudanças podem apresentar potencial para outras aplicações do material, onde a questão da flexibilidade se faça necessária.

Abstract The bone fixation devices, conventional metallic cranium used in surgery have presented some problems, such as corrosion, inflammation and infection, and a lower mechanically newly formed bone structure due to the atrophy caused by the difference in stiffness between metal and bone. These reasons have led to increased interest in bioreabsorbable polymeric devices. The most bioresorbable polymers used in this application belong to the family of poly (α-hydroxy acids), which are characterized degrade by hydrolysis of its ester linkages, such as copolymer poly (L-lactic acid-co-D, L lactic acid) (PLDLA). In this work was investigated some effects of the addition poly (caprolactone triol), PCL-T in the PLDLA. Pins were prepared by melting in the 100/0, 90/10, 70/30 and 50/50 (w/w) compositions, PLDLA/PCL-T. The pins were characterized by different methods (DSC, SEM and mechanical test). The in vitro pins degradation was investigated. It was observed that the addition of PCL-T of PLDLA modifies the mechanical properties, morphological, we conclude that PLDLA/PCL-T can be a potential material for various applications, where the question of flexibility to make necessary.

This study aims the synthesis of copolymers of poly (l-lactic acid) and polycaprolactone by ring opening polymerization. The reactions between l-lactide (LLA) and ε-caprolactone (CL) monomers, in 100/0, 95/5, 90/10 and 80/20 LLA/CL mass ratios, were conducted in refluxing toluene, using Stannous octoate as iniciator, methanol as co-iniciator and inert atmosphere (N2). The reaction medium was maintained under stirring at 120 °C for 24 hours. The samples were characterized by carbon-13 and proton nuclear magnetic resonance (C13-NMR and H1-NMR), and gel permeation chromatography (GPC). Monomers were characterized by thermogravimetry (TG). Copolymers were formed only in samples containing 20 wt% ε-caprolactone. NMR spectra of the other samples showed no evidence of CL units. This fact may be associated with the low-temperature volatilization of monomers. The GPC analysis showed that the increase of CL concentration decrease the molecular weight of copolymers.

The application of polymer-based bioresorbable temporary devices in the medical field grows continuously, and professionals from several areas act to solve problems related to body functions lost due to diseases, accidents or natural wear. Here we study the influence from poly(caprolactonetriol) (PCL-T) on the degeneration process in the copolymer poly(L-co-DL-lactic acid) (PLDLA) membrane, by producing PLDLA/PCL-T blends with 90/10, 70/30 and 50/50 relative concentrations. The data for in vitro degradation showed that PCL-T decreases the rate of PLDLA. This was obtained with the following techniques: Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), Gel Permeation Chromatography (GPC) and Scanning Electron Microscopy (SEM). Therefore, it is possible to vary the membrane degradation rate by changing the blend composition, which is a tool to tailor a biomaterial.

Poly (L-co-D,L lactic acid) (PLDLA) is an important biomaterial because of its biocompatibility properties that promote cellular regeneration and growth. The aim of this study was to evaluate the polymer-tissue interaction of PLDLA implants in the dorsal subcutaneous tissue of male Wistar rats at various intervals (2, 7, 15, 30, 60 and 90 days) after implantation. Physical properties such as the glass transition point (Tg), degradation behavior and other mechanical properties were characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), gel permeation chromatography (GPC), scanning electron microscopy (SEM) and tension tests. Analysis of the degradation of PLDLA membranes in vitro showed that the polymer became crystalline as a function of the degradation time. Mechanical tension tests showed that the polymer behaved like a ductile material: when subjected to constant tension it initially suffered deformation, then elongation and finally ruptured. TGA/MEV provided evidence of PLDLA membrane degradation. For histological analysis, samples from each group were processed in xylol/paraffin, except for the 60 - and 90 - day samples. Each of the latter samples was divided in two: one half was treated with xylol/paraffin and the other with historesin. Light microscopy showed the adhesion of cells to the biomaterial, the formation of a conjunctive capsule around the implant, the presence of epithelioid cells, the formation of foreign body giant cells and angiogenesis. During degradation, the polymer showed a 'lace' - like appearance when processed in xylol/paraffin compared to the formation of "centripetal cracks in the form of glove fingers" when embedded in historesin.

Apresentamos um estudo que tem por objetivo compreender os sentidos atribuídos à relação entre a utilização das Tecnologias de Informação e Comunicação (TIC) e a qualidade da educação científica na voz de uma professora de ciências do ensino fundamental de uma escola com infraestrutura material e pedagógica para a utilização desses meios. Para a análise do discurso, recorremos à teoria das vozes de M. Bakhtin. Percebemos que o uso das TIC é visto como qualidade educacional por proporcionar acesso ao conteúdo científico, embora não represente propostas pedagógicas inovadoras, sendo apenas associado ao aumento da motivação dos alunos. A análise também permitiu compreender que essa relação é conformada, em seu discurso, pelas diferentes realidades educacionais em que as TIC são inseridas.

This study aimed to understand the meanings attributed to the relationship between the use of information and communication technology (ICT) and the quality of science education in the voice of a science teacher who works in a school with material and pedagogical structure to incorporate these tools. We used the theory of voices by M. Bakhtin to analyse the discourse. We observed that the use of ICT is seen as educational quality because it provides access to content, and although it does not represent innovating pedagogical proposals it is associated with increased of student motivation. The analysis also showed that this relationship is structured by the different educational realities in which ICT are inserted.

Holocalyx balansae Micheli belongs to the Fabaceae family and is called pau-alecrim in Portuguese. In folk medicine, it is indicated to treat heart, hepatic and digestive upsets, as well as being considered anti-septic and diaphoretic. This work aimed to study the morpho-anatomy of the leaf and stem of this native medicinal species, in order to increase knowledge of the Brazilian flora and to contribute to pharmacognostic quality control. Samples of mature leaves and young stems were fixed and either sectioned free-hand or embedded in glycol-methacrylate and sectioned by microtome, then stained. Microchemical tests and scanning electron microscopy were also performed. The leaves are alternate, compound and paripinnate, and the leaflets have a lanceolate shape. Anomocytic and anisocytic stomata are found exclusively on the abaxial surface. The mesophyll is dorsiventral and the midrib, in cross-section, is flat on both sides, showing one collateral vascular bundle, encircled by a sclerenchymatic and crystalliferous sheath. The rachis and petiole present a collateral vascular bundle with a centric arrangement. The stem presents phellogen localized superficially. In the vascular cylinder, there is a sclerenchymatic sheath and continuous phloem and xylem cylinders, both traversed by narrow rays. Prismatic crystals of calcium oxalate are present in the leaf and stem.

Aiming the development of high-performance biodegradable polymer materials, the properties and the processing behavior of poly(3-hydroxybutyrate), P(3HB), and their blends with poly(epsilon-caprolactone), PCL, have been investigated. The P(3HB) sample, obtained from sugarcane, had a molecular weight of 3.0 x 10(5) g.mol¹, a crystallinity degree of 60%, a glass transition temperature (Tg), at - 0.8 °C, and a melting temperature at 171 °C. The molecular weight of PCL was 0.8 x 10(5) g.mol-1. Specimens of 70/30 wt. (%) P(3HB)/PCL blends obtained by injection molding showed tensile strength of 21.9 (± 0.4) MPa, modulus of 2.2 (± 0.3) GPa, and a relatively high elongation at break, 87 (± 20)%. DSC analyses of this blend showed two Tg´s, at - 10.6 °C for the P(3HB) matrix, and at - 62.9 °C for the PCL domains. The significant decrease on the Tg of P(3HB) evidences a partial miscibility of PCL in P(3HB). According to the Fox equation, the new Tg corresponds to a 92/8 wt. (%) P(3HB)/PCL composition.