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Article
Publication date: 9 September 2013

Jaime A. Ramirez, William P.D. Figueiredo, Joao Francisco C. Vale, Isabela D. Metzker, Rafael G. Santos, Matheus S. Mattos, Elizabeth R.S. Camargos and David A. Lowther

– This paper aims to investigate the electroporation phenomenon in a single cell exposed to ultra short (μs) and high voltage (kV) electric pulses.

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Abstract

Purpose

This paper aims to investigate the electroporation phenomenon in a single cell exposed to ultra short (μs) and high voltage (kV) electric pulses.

Design/methodology/approach

The problem is addressed by two complementary approaches. First, numerical simulations based on an asymptotic approximation derived from the Smoluchowski theory are used to calculate the pore generation, growth and size evolution at the membrane of a spherical cell model, immersed in a suspension medium and consisting of cytoplasm and membrane. The numerical calculations are solved using the finite difference method. Second, an in vitro experiment with LLC-MK2 cells is carried out in which electroporation was monitored with molecules of propidium iodide. This part also comprehended the design and manufacturing of a portable electric pulse generator capable of providing rectangular pulses with amplitude of 1,000 V and duration in the range of 1-μs to 100-μs. The pulse generator is composed of three modules: a high voltage DC source, a control module, and an energy storage and high voltage switching.

Findings

The numerical simulations considered a 5-μm radius cell submitted to a 500 kV/m rectangular electric pulse for 1-μs. The results indicate the formation of around 3,500 pores at the cell membrane, most of them, around 950, located at the poles of the cell aligned to the applied electric pulse, with radii sizes varying from 0.5-nm to 13-nm. The in vitro experiment considered exposition of LLC-MK2 cells to pulses of 200 V, 500 V, and 700 V, and 1-μs. Images from fluorescence microscopy exhibit the LLC-MK2 cells with intense red, a strong evidence of the electroporation.

Originality/value

The work presents a thorough study of the electroporation phenomenon combining two complementary approaches, a rigorous numerical simulation and a detailed in vitro experiment.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 32 no. 5
Type: Research Article
ISSN: 0332-1649

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Book part
Publication date: 23 March 2017

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.

Details

Advances in Environmental Accounting & Management: Social and Environmental Accounting in Brazil
Type: Book
ISBN: 978-1-78635-376-4

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Abstract

Details

Labor Relations in Globalized Food
Type: Book
ISBN: 978-1-78350-711-5

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Article
Publication date: 21 September 2012

Roberta de Castro Souza and João Amato Neto

The objective of this paper is to characterise the transactions between European buyers and Brazilian mango and grape producers.

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Abstract

Purpose

The objective of this paper is to characterise the transactions between European buyers and Brazilian mango and grape producers.

Design/methodology/approach

The method selected for this paper was multiple case studies. The Brazilian mango and grape supply chains' export activities to Europe were investigated. The field research was undertaken in Brazil, Germany, The Netherlands and the UK. In total, 41 face‐to‐face interviews were carried out.

Findings

The supermarkets' literature tends to generalise the strategies of retailers focusing on differentiation and preferred suppliers. However, in empirical research conducted in the UK, Germany and The Netherlands it is possible to conclude that the procurement strategies of supermarkets can vary sharply. The results reveal the presence of different agents who demand different quality standards. The level of intensity depends on consumer behaviour, the features of product commercialised and the characteristics of the production segment in each country.

Research limitations/implications

First, in relation to the empirical method there is a limitation because the case study does not allow statistical generalisation. Consequently, it will be interesting to undertake quantitative research in order to quantify the variables presented and their impact on the structure of value chains. Second, the research focuses only on two stages of the supply chain, producers and buyers.

Practical implications

The differences between UK and German supermarkets challenge the supermarket literature, which tends to generalise the strategies of retailers focusing on differentiation and preferred suppliers.

Originality/value

The study shows that the issue of influence and activities of retail agents along the value chain can be analysed taking several variables into consideration: the products commercialised; the distribution segment; and the consumer market. This result opens the way for analysing different structures of the value chain and the impact of these differences on the entry of producers for developing countries into the global market.

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Article
Publication date: 14 February 2024

Rafael Borim-de-Souza, Yasmin Shawani Fernandes, Pablo Henrique Paschoal Capucho, Bárbara Galleli and João Gabriel Dias dos Santos

This paper aims to analyze what Samarco and Brazilian magazines speak and say about Mariana’s environmental crime. Discover their doxa in this subject. Interpret the speakings…

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Abstract

Purpose

This paper aims to analyze what Samarco and Brazilian magazines speak and say about Mariana’s environmental crime. Discover their doxa in this subject. Interpret the speakings, sayings and doxas through the theories of the treadmills of production, crime and law.

Design/methodology/approach

It is a qualitative and documental research and a narrative analysis. Regarding the documents: 45 were from public authorities, 14 from Samarco Mineração S.A. and 73 from Brazilian magazines. Theoretically, the authors resorted to Bourdieusian sociology (speaking, saying and doxa) and the treadmills of production, crime and law theories.

Findings

Samarco: speaking – mission statements; saying – detailed information and economic and financial concerns; doxa – assistance discourse. Brazilian magazines: speaking – external agents; saying – agreements; doxa – attribution, aggravations, historical facts, impacts and protests.

Research limitations/implications

The absence of discussions that addressed this fatality, with its respective consequences, from an agenda that exposed and denounced how it exacerbated race, class and gender inequalities.

Practical implications

Regarding Mariana’s environmental crime: Samarco Mineração S.A. speaks and says through the treadmill of production theory and supports its doxa through the treadmill of crime theory, and Brazilian magazines speak and say through the treadmill of law theory and support their doxa through the treadmill of crime theory.

Social implications

To provoke reflections on the relationship between the mining companies and the communities where they settle to develop their productive activities.

Originality/value

Concerning environmental crime in perspective, submit it to a theoretical interpretation based on sociological references, approach it in a debate linked to environmental criminology, and describe it through narratives exposed by the guilty company and by Brazilian magazines with high circulation.

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Article
Publication date: 3 November 2022

Marcello Angotti, Aracéli Cristina de S. Ferreira, Teresa Eugénio and Manuel Castelo Branco

This study seeks to collaborate with the discussions on the usefulness of the narrative approach in accounting. In this context, this study aims to elaborate small collective…

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Abstract

Purpose

This study seeks to collaborate with the discussions on the usefulness of the narrative approach in accounting. In this context, this study aims to elaborate small collective stories, developed from interviews, to expose the population’s perception of the social and environmental impact (positive and negative externalities) resulting from iron ore mining in the city of Congonhas-Minas Gerais (MG).

Design/methodology/approach

This research, using counternarratives, aims to elaborate small collective stories, developed from 52 interviews, to expose the population’s perception of externalities resulting from the exploitation of iron ore in the city of Congonhas-MG, Brazil, to give more insight for social and environmental accounting reporting. A qualitative investigation is used with a narrative approach that focuses on a specific event in the participants’ lives.

Findings

The authors sought to create a sense of collective experiences of the interviewees through narratives representative of the residents’ perception of externalities in the form of small collective stories. However, it can be observed that the local population recognizes the impact of numerous externalities. Likewise, the use of narratives allows the reader to experience another reality – a reflection on the impact of business activities in a given context. Unlike conventional corporate social reporting, models based on qualitative information can be inclusive, produced by/for the community toward action that transforms the local reality.

Originality/value

This study intends to contribute to the debate on reporting models that are developed by and for external stakeholders. This approach has the potential to improve participants’ both awareness and engagement, supporting transformative social action. This study makes several contributions. It contributes to the literature with a narrative approach, which is not often used in the accounting literature; it brings insights from the Latin American context, which is especially valuable given how the Anglo-American accounting literature includes few papers addressing this context; it presents the view of marginalized communities that are too often overlooked (this narrative approach offers important insights into the lived experience of people at a very granular level).

Details

Meditari Accountancy Research, vol. 32 no. 1
Type: Research Article
ISSN: 2049-372X

Keywords

Available. Content available
Book part
Publication date: 22 February 2023

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Abstract

Details

The Brazilian Way of Doing Public Administration
Type: Book
ISBN: 978-1-80262-655-1

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Book part
Publication date: 9 March 2015

Claudia Job Schmitt

The chapter seeks to reflect on the dynamics of the reconstruction of family farming and peasant agriculture in agrarian reform settlements (“assentamentos”) in Brazil, exploring…

Abstract

The chapter seeks to reflect on the dynamics of the reconstruction of family farming and peasant agriculture in agrarian reform settlements (“assentamentos”) in Brazil, exploring the limits and potential of government food purchases from family farming, particularly the Food Acquisition Program (Programa de Aquisição de Alimentos – PAA), in the creation of alternative paths of rural development. The work analyzes the different strategies through which farmers and their organizations mobilize public policy instruments and market connections, expanding their room for maneuver and agency capacity. Research was conducted in the Baixo Sul Territory of the state of Bahia, focusing the heterogeneous web of social organizations involved in the implementation of the Food Acquisition Program in this setting.

Details

Constructing a New Framework for Rural Development
Type: Book
ISBN: 978-1-78441-622-5

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Article
Publication date: 10 April 2017

João Rafael Galvão, Licinio Moreira, Gonçalo Gaspar, Samuel Vindeirinho and Sérgio Leitão

Taking into account the current relevance of the concept of smart city connected with the Internet of Things, this work aims to study the implementation of this concept by…

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Abstract

Purpose

Taking into account the current relevance of the concept of smart city connected with the Internet of Things, this work aims to study the implementation of this concept by applying a new energy model in an existing public building. The purpose of this paper is to enhance the sustainability and energy autonomy of the building.

Design/methodology/approach

The building referred to in the case study is a library, and simulations related to the ongoing study are based on an energy audit, comprising a survey on electrical and thermal energy consumption. The innovative proposed model consists of a mix of energy production processes based on photovoltaic panels and biomass boilers. Economic analysis of the energy model has already yielded some results regarding the payback on investment, as well as avoided emissions in the context of development of a low-carbon economy with avoided emissions and socioeconomic advantages.

Findings

It is possible to enhance the sustainability of the library studied by the retrofit of the current energy system. With the integration of photovoltaic panels and the conversion or replacement of boilers from natural gas to biomass, the GHG emissions could drop around 121 t CO2 per year. Another benefit would be the inclusion of endogenous resources over imported energy resources. The payback period for the measures proposed ranges from 2.5 to 8 years, proving that the increase in environmental sustainability is viable.

Originality/value

The intention here is to implement the concept of smart city, in more sustainable buildings, bringing them to the lowest possible energy consumption levels, hence increasing performance and comfort. Also, taking into account that the energy-consuming buildings are already constructed, it is urgent to reconvert them to lower the use of energy and emissions using technologies based on renewable energy, boosting the use of local resources.

Details

Management of Environmental Quality: An International Journal, vol. 28 no. 3
Type: Research Article
ISSN: 1477-7835

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Article
Publication date: 11 July 2016

Paul B Spooner

– The purpose of this paper is to review the present status and relationship of Macau to Brazil and to a provide the historical context for that relationship.

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Abstract

Purpose

The purpose of this paper is to review the present status and relationship of Macau to Brazil and to a provide the historical context for that relationship.

Design/methodology/approach

This paper takes the approach of interviews, an extensive review of Portuguese and English language periodicals of Macau, Brazil, USA extending back to 1950s, and a review of the key secondary literature.

Findings

Efforts to promote a relationship between Macau and Brazil since 1961 have been laudable, but have not resulted in either a meaningful economic relationship or systematic cultural links.

Practical implications

Trade-wise Hong Kong is much better positioned to interface with Brazil than Macau. Brazil established strategic trade and diplomatic relations with China 25 years prior to Macau’s return to China in 1999 and without any intermediation by the city.

Social implications

A strategic plan is needed to develop Macau’s links to Brazil based upon that country’s vast array of cultural strengths, which include sports, music, dance, religion, language, education, cuisine, environment resources, technology and the presence of a significant Macanese Diaspora.

Originality/value

There is a shortage of analysis on the status of the relationship of Brazil to China, Macau and the Lusophone world.

Details

Asian Education and Development Studies, vol. 5 no. 3
Type: Research Article
ISSN: 2046-3162

Keywords

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