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The purpose of the present study was to perform a preliminary analysis of the fitting of different fiber-reinforced composite (GFRC) posts to tooth root canals and determine the resin cement layer thickness. The following GFRC posts were assessed: bundle posts (Rebilda GTTM, VOCO, Germany), sleeve system (SAPTM, Angelus Ind, Brazil), and accessory posts (ReforpinTM, Angelus, Brazil). Twenty-four freshly extracted mandibular single-rooted pre-molars were endodontically treated and divided into six groups, according to the type of GFRC post and resin cement (self-adhesive or conventional dual-cured). Then, specimens were cross-sectioned and inspected by optical microscopy regarding the cement layer thickness and presence of defects such as pores, voids, or fissures were assessed. Bundle and accessory posts revealed a regular distribution of resin cement with a lower number of voids than found with sleeve systems. The sleeve system posts showed poor fitting at the apical portion of the root canals. The type of resin cement did not affect the thickness of the interface, although both bundle and accessory posts allow a better distribution of resin cement and fibers. The present preliminary study reveals interesting insights on the fitting of bundle and accessory posts to root dentin and resin cement layer thickness in oval-shape root canals. The sleeve system posts showed adequate fitting only at the coronal portion of the canals. [ABSTRACT FROM AUTHOR]

The Local Port Environmental Agenda, created by the Interministerial Commission for Sea Resources in 1998, has the function of providing instruments for the agreement between local environmental demands and the development of port operations in a sustainable way. Within the scope of the thematic axes are the Sustainability Reports, required by Law No. 13,303/2016, and which are important in the analysis of compliance of environmental actions, including the identification of sustainable practices. With this prism, research was carried out in the 09 main public ports of the Northeast, where the compliance of these reports and their interface with the actions of the Local Port Environmental Agenda was analyzed, with the establishment of an indicator. The methodological approach was qualitative research, through multiple case studies with documental and bibliographic research procedure. The research results showed that most of the public port facilities studied, despite producing the referred reports mostly, established a satisfactory interface between them and their Environmental Agendas. [ABSTRACT FROM AUTHOR]

The population ageing, an effect of the accelerated demographic transition in Brazil, highlights the necessity of designing to fulfill the demands from this population segment, which, despite comprising the senior age range, stays active and maintains its autonomy in day-to-day activities. Thus, this study had the intent of discussing, from the perspective of ergonomics, the interface design standards in residential washing machine models available on the Brazilian market, in order to present a redesign proposal envisioning better experiences for elderly users. [ABSTRACT FROM AUTHOR]

BACKGROUND: Work activity integrates the tasks to be performed, the means of work available, the instructions, the rules to be observed, the particular factors related to the individuals (skills, inner state), and the effects both on the task and on the operator. By analyzing the activity, the different logics and conflicts in the design of production systems are revealed. OBJECTIVE: To show how the work activity can support the transformation of the working conditions, when revealed by an ergonomic intervention, by integrating the different design standpoints, which are always present in the project's work situations. METHODS: For this case study, the Ergonomic Work Analysis (EWA) was used on the staff that serves meals at a new university restaurant in Rio de Janeiro (Brazil) with a focus on the portioning of the transported ready-cooked meals and the variability related thereto. The results of observations, verbalizations, self-confrontations and strategy analysis, collected through field notes and audio and photographic records, became a final report submitted to the directors of the university restaurant. RESULTS: This research showed that the work activity of the serving maids helped to reveal the different logics of the heterogeneous actors in the design of the work situation under analysis. The work activity, when revealed by an ergonomic intervention, can be an interface during the design process to articulate these different logics and to support the dialog among different design standpoints. Thus, the concept of fixed portioning became a concept of flexible portioning, which provided the serving maids with an increased autonomy level at the counter, thus improving both the quality of services and the working conditions of those involved therewith. CONCLUSIONS: The activity-focused design can be understood as an ongoing, multiple logical process whereby workers bring the design into their workplaces, which reveals aspects of their own activity, thus helping to change the initial concepts. The ergonomic intervention, based on the revealed activity, helps to highlight the existence of different logics and also to support the actors in articulating their own logics during the design process. [ABSTRACT FROM AUTHOR]

Brazil has a well established ethanol production program based on sugarcane. Sugarcane bagasse and straw are the main by-products that may be used as reinforcement in natural fiber composites. Current work evaluated the influence of fiber insertion within a polypropylene (PP) matrix by tensile, TGA and DSC measurements. Thus, the mechanical properties, weight loss, degradation, melting and crystallization temperatures, heat of melting and crystallization and percentage of crystallinity were attained. Fiber insertion in the matrix improved the tensile modulus and changed the thermal stability of composites (intermediary between neat fibers and PP). The incorporation of natural fibers in PP promoted also apparent Tc and ΔHc increases. As a conclusion, the fibers added to polypropylene increased the nucleating ability, accelerating the crystallization process, improving the mechanical properties and consequently the fiber/matrix interaction. [ABSTRACT FROM AUTHOR]