Camila Fernandes Higa, Thatyanne Gradowski, Selene Elifio-Esposito, Marcelo Fernandes de Oliveira, Paulo Inforçatti, Jorge Vicente Lopes da Silva, Fred Lacerda Amorim and Michelle Sostag Meruvia
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…
Abstract
Purpose
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.
Design/methodology/approach
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).
Findings
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.
Originality/value
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.
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Grazielle de Oliveira Setti, Jorge Vicente Lopes da Silva, Marcelo Fernandes de Oliveira, Izaque Alves Maia, Dosil Pereira de Jesus, Raluca Savu, Thebano Emilio de Almeida Santos, Rita de Cássia Zacardi de Souza and Ednan Joanni
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Originality/value
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.
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Grazielle de Oliveira Setti, Marcelo Fernandes de Oliveira, Izaque Alves Maia, Jorge Vicente Lopes da Silva, Raluca Savu and Ednan Joanni
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…
Abstract
Purpose
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.
Design/methodology/approach
Fabrication of Nylon 12 (Duraform PA®) samples using different laser power levels and their characterization by tensile testing, roughness and Raman scattering measurements.
Findings
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.
Originality/value
Quantitative evaluation and correlation between mechanical properties and surface properties of SLS-made samples.
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Grazielle de Oliveira Setti, Marcelo Fernandes de Oliveira, Izaque Alves Maia, Jorge Vicente Lopes da Silva and Ednan Joanni
This paper aims to demonstrate the functionalization of polyamide parts made by selective laser sintering (SLS) for application as substrates for chemical analysis by…
Abstract
Purpose
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).
Design/methodology/approach
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.
Findings
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.
Originality/value
ZnO nanostructures were grown directly on untreated surfaces of SLS-made polyamide. These substrates were used for chemical analysis by SERS.
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Barbara de Lima Voss, David Bernard Carter and Bruno Meirelles Salotti
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…
Abstract
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.
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Fábio Lotti Oliva, Bárbara Ilze Semensato, Daniela Buzzulini Prioste, Eric Jacques Lucien Winandy, Jefferson Luiz Bution, Marcelo Henrique Gomes Couto, Marco Antonio Bottacin, Maria Laura Ferranty Mac Lennan, Pedro Marins Freire Teberga, Ricardo Fernandes Santos, Sanjay Kumar Singh, Sidirley Fabiani da Silva and Silvye Ane Massaini
The purpose of this paper is to analyze the innovation process of organizations representing the main sectors of Brazilian economic activity.
Abstract
Purpose
The purpose of this paper is to analyze the innovation process of organizations representing the main sectors of Brazilian economic activity.
Design/methodology/approach
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.
Findings
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.
Practical implications
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.
Originality/value
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.
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Yasmin Shawani Fernandes, Paulo Marcelo Ferrarese Pegino, Eduardo Augusto do Rosário Contani and Reginaldo Fidelis
This study proposes a method for analyzing the sustainability of companies according to the Corporate Sustainability Index (ISE B3) while considering environmental, social and…
Abstract
Purpose
This study proposes a method for analyzing the sustainability of companies according to the Corporate Sustainability Index (ISE B3) while considering environmental, social and governance (ESG) dimensions.
Design/methodology/approach
As a quantitative and descriptive work, our study is based on analyses of responses to ISE B3 questionnaires. We consider 12 scenarios involving the allocation of different weights to important ESG dimensions and use the TOPSIS multicriteria decision-making method to evaluate companies in Brazil.
Findings
The results provide empirical evidence on the importance of balanced approach among the ESG dimensions and reflect the need for regulations and incentives to promote balanced ESG practices. We also identify companies with consistently good sustainability practices, such as Natura, those that deliver poor performance, such as Iochpe-Maxion S.A. and Azul S.A.
Research limitations/implications
We contribute to the literature by integrating a multicriteria methodology into the assessment of corporate sustainability, demonstrating the effectiveness of TOPSIS in different scenarios. We emphasize the importance of balancing the ESG dimensions, and in doing so provide novel perspectives in research.
Practical implications
Our findings offer a practical framework for managers to evaluate and refine their ESG strategies by using benchmarks from industry leaders. Policymakers can use them to formulate regulations and incentives that promote balanced ESG practices.
Originality/value
Our work clarifies the application of TOPSIS to several ESG-based scenarios and presents a comprehensive strategy for evaluating corporate sustainability. Our model can be reproduced and customized in diverse settings and contributes to the literature on corporate sustainability.
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Jiju Antony, Elisabeth Viles, Alexandre Fonseca Torres, Taynara Incerti de Paula, Marcelo Machado Fernandes and Elizabeth A. Cudney
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.
Abstract
Purpose
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.
Design/methodology/approach
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).
Findings
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.
Practical implications
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.
Originality/value
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.
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Ione da Silva Jovino, Anete Abramowicz and Beatriz Fernandes Ferreira Portela
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…
Abstract
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.
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Marcelo Caetano de Oliveira, Paula Nogueira Curi, Rafael Pio, Daniela da Hora Farias, Marcio Roberto Rigote, Maria Cecília Evangelista Vasconcelos Schiassi, Moacir Pasqual and Vanessa Rios de Souza
The native species from western Mato Grosso do Sul provide fruits with unique sensory characteristics and high nutrient concentrations. Tropical fruit consumption is increasing…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Originality/value
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.