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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.

This paper aims to describe the obtainment of Ti-6Al-4V parts with a hierarchical arrangement of pores by additive manufacturing, aiming at designing orthopedic implants.

The experimental methodology compares microstructural and mechanical properties of Menger pre-fractal sponges of Ti-6Al-4V alloy, manufactured by laser powder bed fusion (LPBF) and electron beam powder bed fusion (EBPBF), with three different porosity volumes. The pore arrangement followed the formation sequence of the Menger sponge, with hierarchical order from 1 to 3.

The LPBF parts presented a martensitic microstructure, while the EBPBF parts presented an α + ß microstructure, independently of its wall thickness. The LPBF parts presented higher mechanical resistance and effective stiffness than the EBPBF parts with similar porosity volume. The stiffness values of the Menger pre-fractal sponges of Ti-6Al-4V alloy, between 4 and 29 GPa, are comparable to those of the cortical bone. Furthermore, the deformation behavior presented by the Menger pre-fractal sponges of Ti-6Al-4V alloy did not follow the Gibson and Ashby model's prediction.

To the best of the authors' knowledge, this is the first study to obtain Menger pre-fractal sponges of Ti-6Al-4V alloy by LPBF and EBPBF. The deformation behavior of the obtained porous parts was contrasted with the Gibson and Ashby model's prediction.

This study aims to report the development of an open-source syringe extrusion head for shear-thinning materials. The target is to adapt open-source 3D printers to be helpful in research lines that use gels, hydrogels, pastes, inks, and bio-inks.

This hardware was designed to be compatible with a Graber i3-based 3D printer; nevertheless, it can be easily adapted to other open-source 3D printers.

The extrusion head successfully deposits the material during the 3D printing process. It was validated fabricating geometries that include scaffold structures, which are a possible application of bioprinting for tissue engineering. As reported, the extruded filaments allowed the porous samples' structuration.

This system expands the applications of open-source 3D printers used at the laboratory scale. It enables low-cost access to research areas such as tissue engineering and biofabrication, energy storage devices and food 3D printing.

The open-source hardware here reported is of simple fabrication, assembly and installation. It uses a Cardan coupling and a three guides system to transfer the stepper motor motion. This approach allows continuous movement transfer to the syringe piston, producing an adequate deposition or retraction. Thus, the effect of misalignments is avoided, considering that these latter can cause skipping steps in the motor, directly affecting the deposition.

This study aims to investigate the production of scaffolds by selective laser sintering (SLS) using poly(vinyl alcohol) (PVA) polymer, for in vitro studies, a relatively new and growing area in which scaffolds could be used in the design of three-dimensional models for in vitro disease model or tissue equivalent for safety and effectiveness tests.

The influence of the SLS process parameters laser power, 26 W and 32 W, and number of laser scans, 1, 2, 4 and 6, on the surface microstructure of the samples and on the degree of crystallinity and chemical stability of PVA material, was investigated using powder with particle size of 20-320 µm. Laser sintered PVA samples were subjected to cell culture tests using osteoblastic cells derived from human osteosarcoma (SaOs-2).

The laser power has no significant influence on the microstructure of the laser-sintered samples, however the number of scans has a considerable influence on the sintering degree; the SLS process causes a decrease in the degree of crystallinity and changes the chemical structure of the as-received PVA, especially when using higher laser power and more number of scans. Preliminary in vitro cell culture tests show that the laser-sintered PVA material is biocompatible with SaOs-2 cells.

SLS offers good potential for the fabrication of scaffolds and thus, may be applied as an alternative to conventional scaffold fabrication processes to overcome their limitations.

The purpose of this paper is to compare the results from mechanical testing with measurements of surface-dependent properties performed on polyamide parts made by selective laser sintering (SLS) to assess a possible correlation between them.

Fabrication of Nylon 12 (Duraform PA®) samples using different laser power levels and their characterization by tensile testing, roughness and Raman scattering measurements.

Among the surface methods investigated, the results from Raman spectroscopy are the best ones, but methods dependent on surface analysis are not really suitable as indicators of the mechanical properties. The correlation coefficients for linear fitting obtained when the normalized results of mechanical properties are plotted against the surface properties are too low. Furthermore, the ambiguity between surface and mechanical data makes it impossible to use these surface properties for prediction purposes in the industrial environment.

Quantitative evaluation and correlation between mechanical properties and surface properties of SLS-made samples.

The purpose of this paper is to characterize polyamide parts prepared by the SLS process using techniques that are dependent on surface properties and compare the results to density measurements in order to assess which technique better reflects the degree of densification achieved using different laser power levels.

Fabrication of Nylon 12 (Duraform PA) samples and their characterization by apparent density measurements, perfilometry, Raman spectroscopy, scanning electron microscopy, specific surface area and contact angle measurements.

Methods dependent on surface analysis are not suitable indicators of the degree of sample densification. Among the surface methods, the results from Raman spectroscopy are the ones with the best performance. Incipient sintering of the superficial layers and raw material powder on the surface, inherent to the parts made by the SLS process, strongly interfere with the characterization.

Quantitative comparison of a number of surface probing methods for monitoring densification of SLS parts. Characterization of sample surfaces with and without raw material powder.

This paper aims to demonstrate the functionalization of polyamide parts made by selective laser sintering (SLS) for application as substrates for chemical analysis by surface-enhanced Raman scattering (SERS).

Fabrication of Nylon 12 (Duraform PA®) samples using two laser power levels and deposition of a layer of gold-coated zinc oxide nanostructures. Performance of these substrates in the detection of a known compound was tested by Raman spectroscopy.

The hydrothermal synthesis proved to be a good method for functionalizing the surface of polyamide parts made by the SLS process. By varying the synthesis temperature, ZnO nanoparticles and nanorods attached to the sample surfaces could be obtained. The degree of sample sintering had an effect on the growth of the nanostructures. The gold-coated functionalized surfaces enhanced the Raman signal from crystal violet by more than three orders of magnitude. ZnO nanorods grown on well-sintered SLS parts showed the best performance from the set of samples tested in this work.

ZnO nanostructures were grown directly on untreated surfaces of SLS-made polyamide. These substrates were used for chemical analysis by SERS.

Milton Nascimento is one of the most prolific Brazilian singers and songwriters of all time, an artist who has formed friendships and made songs with a host of Brazilian artists, with international stars from Latin America, and with artists abroad. Milton’s repertoire has made its way into the fabric of musical compilations of Brazilian music for international listeners. Perhaps unbeknownst to these international listeners, Milton, as an Afro-Brazilian artist, reflects a complex and paradoxical relationship to “race” in his music – at times openly touching upon racial themes, even during an area when the government forbade open discussion of racial tension in Brazil – but at times signifying race more subtly, either through subtle references to diversity in Brazil or through the very elements of his music.

This study aims to examine the impact that diagnostic factors such as duration of diagnostic period, number of professionals consulted and perceived social support have on parental stress during the diagnostic process of autism spectrum disorder (ASD).

Forty parents of 2–18 year-old children/adolescents with a formal ASD diagnosis recruited from five specialized private clinics in Lisbon completed a survey which included diagnostic questionnaire, parental stress scale and social support scale from April to December 2022.

Data analysis indicated that the mean age of the diagnosis was 5.6 years with a delay of 3.95 years from first concern until final diagnosis. On average, parents consulted a mean of 3.62 professionals. Other findings indicated that as age of parents increased, levels of parental stress decreased. Parents with higher levels of social support had lower levels of parental stress. Furthermore, higher age of child at first concern predicted higher affective social support.

This study reflects on the experience of obtaining the ASD diagnosis in Portugal, raising awareness on the importance of providing early detection and social support for distressed parents.