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Additive manufacturing (AM) has emerged over the past years as a key technology in aircraft structural components’ manufacturing. This paper aims to describe the numerical analysis and experimental testing of five wing ribs with different 2D topologies manufactured with polylactic acid (PLA) using the fused deposition modeling technology. The main purpose is to determine the best wing rib topology in terms of strength, stiffness and mass.

Numerical analyses are performed using Ansys Workbench’s static structural analysis for two distinct loading cases. In the first loading, the chord-wise distributed load, resulting from wing lift, is replaced by two equivalent concentrated loads at the leading and trailing edges. This simplification allows the numerical results to be experimentally validated. The second loading has distributed loads applied on the upper and on the lower surfaces of the wing rib to produce a more realistic structural response. Experimental tests are performed with the first loading case to determine maximum displacement and failure loads of the wing ribs studied. SEM is used to analyze fracture surfaces.

From the five different PLA printed wing rib topologies studied, it is found that truss type configurations are the more structural efficient, that is, truss topologies exhibit better specific strength and specific stiffness. Additionally, the limiting factor in the design of these wing ribs is stiffness rather than strength.

The work identifies the kind of structural topologies that are best suited for 2D wing ribs obtained by AM and leads the way to more complex and more efficient structural layouts to be explored in the future using topology optimization coupled with simple Finite Element Analysis (FEA).

We present a critical literature review debating Brazilian research on social and environmental accounting (SEA). The aim of this study is to understand the role of politics in the construction of hegemonies in SEA research in Brazil. In particular, we examine the role of hegemony in relation to the co-option of SEA literature and sustainability in the Brazilian context by the logic of development for economic growth in emerging economies. The methodological approach adopts a post-structural perspective that reflects Laclau and Mouffe’s discourse theory. The study employs a hermeneutical, rhetorical approach to understand and classify 352 Brazilian research articles on SEA. We employ Brown and Fraser’s (2006) categorizations of SEA literature to help in our analysis: the business case, the stakeholder–accountability approach, and the critical case. We argue that the business case is prominent in Brazilian studies. Second-stage analysis suggests that the major themes under discussion include measurement, consulting, and descriptive approach. We argue that these themes illustrate the degree of influence of the hegemonic politics relevant to emerging economics, as these themes predominantly concern economic growth and a capitalist context. This paper discusses trends and practices in the Brazilian literature on SEA and argues that the focus means that SEA avoids critical debates of the role of capitalist logics in an emerging economy concerning sustainability. We urge the Brazilian academy to understand the implications of its reifying agenda and engage, counter-hegemonically, in a social and political agenda beyond the hegemonic support of a particular set of capitalist interests.

People are increasingly concerned about food and health and seek for functional and sugar-free products. However, there are technological challenges when adding functional components and substituting sugar in foods. Thus, the purpose of this paper is to evaluate the influence of packaging and storage time on the sensory profile of functional diet guava preserve added with prebiotics, supporting the development of functional and sugar-free products and contributing to the product variety in the market.

A two-factor full factorial design was conducted in triplications that evaluated transparent and opaque packaging vs storage time (six months). The products were stored in packages with different light permeability (transparent and opaque). Quantitative descriptive analysis (QDA) and acceptance tests were performed.

The packaging material did not affect the sensory changes of functional diet guava preserve during the six months of storage. QDA test showed that from three months of storage the original characteristics of the product were lost and a slight decrease in overall acceptance was observed after four and six months. However, during the six months the products had good acceptance; consequently, it was not possible to establish their rejection before this period.

More detailed studies regarding a longer storage period, including the physical and chemical measurements must be done to clarify other points about the influence of packaging and storage time on the sensory profile of functional diet guava preserve added with prebiotics. Therefore, researchers are encouraged to test the proposed propositions further.

The development of a functional and sugar-free preserve is a good alternative to provide a product that meets the actual consumer desires and adds value to the product. However, there are technological challenges when adding functional components and substituting sugar in foods. Thus, this study provides important information for the development of sugar-free and functional products, and to prolong their shelf life.

There are few studies with respect to the sensory aspects during the storage of functional preserves. Thus, this work will aid future studies, supporting the development of functional and sugar-free products and contributing to the product variety in the market.