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One of the main causes of long-term prosthetic abandonment is the lack of ownership over the prosthesis, which was caused mainly by the absence of sensory information regarding the lost limb. The period where the patient learns how to interact with a prosthetic device is critical in rehabilitation. This ideally happens within the first months after amputation, which is also a period associated with the consolidation of brain changes. Different studies have shown that the introduction of feedback mechanisms can be crucial to bypass the lack of sensorial information. To develop a biofeedback system for the rehabilitation of transfemoral amputees – controlled via electromyographic (EMG) activity from the leg muscles – that can provide real-time visual and/or vibratory feedback for the user.

The system uses surface EMG to control two feedback mechanisms, which are the knee joint of a prosthetic leg of a humanoid avatar in a virtual reality (VR) environment (visual feedback) and a matrix of 16 vibrotactile actuators placed in the back of the user (vibratory feedback). Data acquisition was inside a Faraday Cage using an OpenEphys® acquisition board for the surface EMG recordings. The tasks were performed on able-bodied participants, with no amputation, and for this, the dominant leg of the user was immobilized using an orthopedic boot fixed on the chair, allowing only isometric contractions of target muscles, according to the Surface EMG for Non-Invasive Assessment of Muscles (SENIAM) standard. The authors test the effectiveness of combining vibratory and visual feedback and how task difficulty affects overall performance.

The authors' results show no negative interference combining both feedback modalities and that performance peaked at the intermediate difficulty. These results provide powerful insights of what can be accomplished with the population of amputee people. By using this biofeedback system, the authors expect to engage another sensory modality in the process of spatial representation of a virtual leg, bypassing the lack of information associated with the disruption of afferent pathways following amputation.

The authors developed a showcase with a new protocol and feedback mechanisms showing the protocol's safety, efficiency and reliability. However, since this system is designed for patients with leg amputation, the full extent of the effects of the biofeedback training can only be assessed after the evaluation with the amputees, and the results obtained so far establish a safe and operational protocol to accomplish this.

In this study, the authors proposed a new biofeedback device intended to be used in the preprosthetic rehabilitation phase for people with transfemoral amputation. With this new system, the authors propose a mechanism to bypass the lack of sensory information from a virtual prosthesis and help to assimilate visual and vibrotactile stimuli as a cue for movement representation.

With this new system, the authors propose a mechanism to bypass the lack of sensory information from a virtual prosthesis and help to assimilate visual and vibrotactile stimuli as a cue for movement representation.

The authors' results show that all users were capable of recognizing both feedback modalities, both separate and combined, being able to respond accordingly throughout the tasks. The authors also show that for a one-session protocol, the last difficulty level imposed a greater challenge for most users, explained by the significant drop in performance disregarding the feedback modality. Lastly, the authors believe this paradigm can provide a better process for the embodiment of prosthetic devices, fulfilling the lack of sensory information for the users.

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 present the proposition of a new experimental method for obtaining very crucial data of the structural steel that is used in the tank of oil filled power transformers, namely, the volumetric losses and the magnetic permeability, both in function of the density of magnetic flux. Although these data are not usually available, they are fundamental for helping the transformer designer in avoiding the occurrence of hot spots in the transformer tank. The adoption of a conventional Epstein frame has restrictions because of the incompatibility between it and the samples of the steel.

The basis of the proposition is the same as that of the Epstein frame, with significant attention paid to the additional losses in the winding that creates the magnetic flux to the samples in the core. These losses can be significant and are created by the harmonics of current along the windings and are summed to the ohmic losses. For separating these winding losses from the magnetic losses, each sample is made as being the core of a toroidal 1:1 transformer. Thus, two tests with two identic of these toroidal transformers are necessary.

The proposed methodology is simple, because it is very similar to the classical tests of transformers (no-load and short-circuit tests). The process of separation of losses requires only a numerical fitting of curves for adjusting the winding losses as a function of the current amplitude, and the obtained results are coherent with the expected behavior of the magnetic losses and the magnetic permeability of a structural steel.

The method gives very approximate results in comparison to those obtained using the Epstein frame. The influences of the temperature and/or of the skin effect have not been evaluated.

Practical, real and thus confident data of structural steel, such as the magnetic permeability and the volumetric losses (hysteresis and Foucault), become available for the transformer designer to take actions for not only reducing the tank losses but also for avoiding the occurrence of hot spots through computer simulation.

The proposition is very new, as it allows to test steel samples with a size that does not fit to a usual Epstein frame. It takes into account the real influence of harmonic of currents in the losses along the winding of a classical Epstein frame, which has not been so far mentioned. It allows obtaining data of structural steel that had not been considered important until now.

Purpose – Scientific studies have shown that the coastal zone is one of the regions showing great vulnerability to the impacts of global environmental change. For the region, impacts that may directly affect the economy and daily life of the communities of coastal municipalities were predicted. It occurs from phenomena, e.g. temperature rise, sea level rise, salinity, acidification of the seas and extreme events.

Methodology/approach – The mariculture labourers and artisan fishers from the Cocanha beach (Caraguatatuba city, north coast of the state of São Paulo), a lookout group, are the first persons to perceive the environmental change impacts in their daily contact with natural resources. Thus, the aim herein was to (a) verify their perception on the amount and quality of mussels and fish catch and (b) if such changes could be related to global environmental changes. In order to do so, semi-structured interviews with this social group were conducted in November 2009–February 2011 and codified by using the NVIVO8 software.

Findings – The results indicated a decrease in fish stocks and, according to interviewees, such decrease was tied in with changes in fishing, in climate, and in beach landscape. Moreover, the category related to increased water temperature was highly significant, since the fishing and mariculture activities are directly influenced by this factor.

Research limitations – The perception evaluation through interviews with artisanal fishermen and shellfishermen implies that many subjective aspects are present, as well as the role of the media that has published significant information on climate change in the contemporary world.

Originality/value of paper – There are few studies that present these perspectives; however, the authors believe that it is possible, while recognising the possible limitations of the method, to recognise something that is already perceived by the community and may help to evaluate the reality they face and to contribute actually to the construction of future public policies.

The application of the Internet to traditional business and administrative activities has introduced considerable digitisation and process automation. One key area of development from a research perspective is the use of electronic (e‐)surveys, based on Internet technology. E‐surveys can bring many benefits from a research perspective, including extremely low marginal costs, automation of processes, and the ability to collect and manage very large samples. However, experience in the use of e‐surveys has found considerable challenges in achieving a quality sample frame and response rates. This paper explores the development of an e‐survey tool for assessing information needs of growth enterprises in Brazil. A key learning from the use of the survey is the use of control methods for both improving the response rate, and, as a consequence, the sample frame.

This chapter examines books written by foreign authors which were published in Brazil and censored by the military regime between 1964 and 1985. The study focuses on non-fiction books, using official period documentation, with the goal of conducting an extensive survey of these works as well as examining the reasons why they were censored by the regime. The results of the research lead us to a greater understanding of the reasoning of censorship from within the State and to a greater understanding of the Brazilian military dictatorship as a whole.

Sustainability at the corporate level is interpreted as the approach capable of creating prosperity over long-term horizons through targeted strategic integration, sustainable business system and societal transitions, beyond economic growth, along with environmental quality and social equity. In this context, this article aims to explore the interplay of the relationship between environmental innovation and corporate sustainability.

A systematic literature review (SLR) was conducted in the Web of Science and Scopus databases for the last six decades to explore the proposed relationship. Data were selected on August 2, 2020, and the analysis period lasted until July 20, 2021. A research protocol consistent with the methodological rigor required in conducting an SLR was prepared for the mapping and analysis of relevant research.

In the last five years, there has been an evolution in research related to green innovation in supply chain management. Based on this evolution, there is a growing concern with the development of sustainable business models, taking into account the motivation to adopt green innovation practices aimed at corporate image. The purpose lies in verifying the organizational capabilities in achieving corporate sustainability practices and economic performance. The results show a greater concentration of studies exploring (1) sustainable business models, (2) the complexity of the sustainability tripod balance, in addition to (3) organizational strategies based on green and competitive practices.

Few works explored the context of small and medium-sized companies, especially those located in emerging and underdeveloped countries. This opens up a promising field of research. The main contributions of this article are related to (1) the presentation of a portfolio of theoretical and methodological approaches on the subject, which allows the exploration of the possibilities of empirical studies; and (2) showing the current status of research on environmental innovation and its impact on corporate sustainability. This article explores the interplay of the relationship between environmental innovation and corporate sustainability and brings state-of-the-art research about the theme.

This study aims to identify the social representation of cloud computing from the perspective of Information Technology (IT) professionals in emerging countries, comparing it with the extant literature on this subject.

Data were collected from IT professionals in Brazil, which was used as a proxy for the emerging countries’ context related to cloud computing. Social Representation Theory was then applied to analyze the data.

Mismatches between theory and practice on cloud computing make it clear that most of the current scientific literature on cloud computing is, to a great extent, based on the context of developed countries rather than on the context of emerging ones.

Errors of inference may have been made during the categorization of the words evoked. Furthermore, Brazil was used as a proxy for the emerging countries’ context related to cloud computing.

IT professionals in emerging countries have quite an operational view of cloud computing. Thus, companies in these countries have to align cloud computing better with new business models and corporate strategies in order to take advantage of the transformational impacts of cloud computing.

IT professionals in emerging countries have failed to notice the strategic value of cloud computing, the new business models enabled by same, the privacy issues related to it and the impact cloud computing adoption can have on the IT costs of an organization. Moreover, mobility can be a paramount issue related to cloud computing in emerging countries – a fact thus far overlooked by academia.