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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 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.

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.

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.

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.

The purpose of this paper is to analyze the innovation process of organizations representing the main sectors of Brazilian economic activity.

The literature review focuses on analyzing the innovation process characteristics regarding the innovation types. The authors carried out interviews with executives and managers in charge of innovation at the leading large companies in the respective sectors analyzed. The data analysis of this qualitative research was structured in three steps. The first step is the analysis of data collected for encoding, the second step, the summarization of the common points presented by the companies in each sector and, finally, the interpretation of these data, aided by triangulation from secondary data that support the analysis of the collected primary data.

The main contribution of this study is to characterize the innovation process of organizations representing the main sectors of the Brazilian economy, with a classification regarding the sectoral innovation standard.

The authors’ intent is that the paper can contribute with a comparative analysis among companies of the same sector and, subsequently, among companies of the different surveyed sectors. Thus, the characterization aims to present the companies’ innovation process and the comparative analysis aims to verify the innovation sectoral patterns. In addition, as implications for management practice, some strategies for better knowledge management in the organization are suggested for each type of innovation.

The main theoretical contribution focuses on the development of a conceptual model that structures the analyzed variables of the constructs “innovation process” and “innovation sectoral patterns”, allowing not only the characterization but also the comparative analysis of the representative organizations present in the sample.

The purpose of the article is to present the results of a critical literature review (CLR) on Design of experiments (DoE) in the service industry.

A critical review of existing literature review across various databases including Scopus, Web of Science, Google Scholar and Emerald Insight were searched for the identification of relevant papers. The authors searched relevant journal articles for a time period of 25 years (1994–2019).

A total of 29 industry case studies of DoE applications were identified spanning healthcare, retail, logistics, education, marketing, after sales and catering business. The industrial experimentation strategies adopted by the case study organisations were screening, factorial designs, Taguchi, response surface method and split-plot. It was apparent that there are only a handful number of papers showing the applications of DoE across the service sector and this motivates for pursuing further research into this topic by the authors.

The findings of the study can be very useful for middle and senior managers to understand the benefits of implementing this powerful technique for increased understanding of service processes, as well as for optimising service performance. Moreover, the paper presents some of the fundamental challenges, as well as skills needed for the successful application of DoE.

To the best of our knowledge, this is the first CLR on DoE and its applications in the service sector. The findings of the study can be beneficial to both academic and industrial communities to understand some of the challenges and fundamental gaps which need to be tackled in the future.

This chapter discusses how young Black people produce social agency through the sphere of culture, based on hip-hop. Divided into two parts, it surveys theses and dissertations produced in Brazilian universities on the subject in the last ten years. In a second moment, it proposes a research methodology that takes young people as narrators of their social experiences, emphasizing how they think about the school space. The work is an exploratory study and seeks the interposition between formal schooling and the cultural practices of hip-hoppers. It intends to affirm hip-hop as a power, an affirmative form of an ethic of life, a way of life, and a way of escaping the established places for poor, Black young people from the suburbs. It is also intended to show how hip-hop, a marginal culture, has triggered a game of cultural positions within the school and displaced provisions of power.

The native species from western Mato Grosso do Sul provide fruits with unique sensory characteristics and high nutrient concentrations. Tropical fruit consumption is increasing due to the growing recognition of the nutritional value. These fruits play important roles through the marketing of their products and nutritionally through their consumption. All fruits are edible and are used in the food industry and well sensory accepted. The purpose of this paper is to verify the physicochemical characteristics, bioactive compounds and antioxidant activity in fruits collected in the Cerrado and Pantanal biomes from western Mato Grosso do Sul.

The fruits of baru, bocaiuva, jatobá, jenipapo and pequi were collected. To characterize them, longitudinal diameter, transverse diameter, total soluble solids, acidity, pH, ascorbic acid, total phenolics, antioxidant capacity, total sugar, glucose and macro and micronutrient contents analysis were performed in triplicate.

Jatobá presented the highest values of vitamin C. For phenolics, baru and jatobá stood out; bocaiuva presented the highest results for sugars, while jatobá was superior for glucose. The fruits with the highest antioxidant capacity, DPPH, were pequi and baru, while via ABTS the jatobá was the highest. Baru presented higher levels of nitrogen, phosphorus, magnesium, copper, zinc and iron. The bocaiuva presented the highest results for potassium and sulfur, the jatobá calcium and manganese. Jenipapo stood out with its boron content. Magnesium presented superior results in the baru, jenipapo and bocaiuva. The results reinforce the diversity of physicochemical characteristics.

The increase of the flow of available information, together with the growth of multicultural influences, the search for wholesome diet and the diversity of flavors and colors make these fruits important regional development tools. Their characteristics encompass national and international exploration potential that arouse consumer interest and contribute to the pursuit of innovations. In addition, the native species mentioned above provide fruits with unique sensory characteristics. Their consumption is increasing in the markets due to the growing recognition of their nutritional value. Therefore, these fruits play important roles, economically, through the marketing of their products and nutritionally through their consumption.

Literature on eco-innovation brings insights that help to understand which factors trigger innovation focused on sustainability in companies. However, when analyzing the studies that comprise such drivers, it appears that most of them were focused only on describing them in isolation. Therefore, this study aims to understand which are the combinations of drivers that favor the adoption of eco-innovation in slaughterhouses located in the Brazilian state of Rio Grande do Sul.

This study has used the crisp-set qualitative comparative analysis (csQCA) as the data analysis technique, in addition to the previous application of Most Similar Different Outcome/Most Different Same Outcome (MSDO/MDSO).

This study identified eight internal and external drivers that explain the differences in performance of eco-innovative and non-innovative slaughterhouses. These drivers generate 13 combinations of factors capable of favoring the adoption of five types of eco-innovation.

A limitation identified was the difficulty to obtain information held by companies on environmental issues. In addition, in each company the authors only approached one respondent.

The use of combinations is identified by companies and governmental and non-governmental organizations to promote eco-innovation in slaughterhouses.

This study may be considered original for its contribution to the improvement of eco-innovation literature by describing how the drivers identified combine to favor the adoption of certain types of eco-innovation. In addition, the authors also made an original use of csQCA, linked with MSDO/MDSO, in the field of eco-innovation.