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In this paper a numerical simulation analysis of a modified stent-based electrode is introduced to be used as a bipolar electrode for radio frequency ablation of tumours located in hollow organs. The purpose of this paper is to study the possibility of achieving a more regular volume of induced lesion with the presented electrode without imperilling the ductal organ where the tumour is located.

Three types of bipolar electrode configurations were considered, formed by two, three and five tubular segments. Numerical simulations were performed considering a tumour located in the bile duct, where two important blood vessels – the portal vein and the hepatic artery – have a significant impact due to the convective heat transfer caused by the blood flow (heat sink effect) which significantly affects the shape of lesion that is intended to induce in order to destroy the tumour.

The results obtained show that the five-segment electrode arrangement allows a regular volume for the induced lesion, independently of the different values of applied voltage considered.

The presented work introduces a numerical simulation analysis on a modified based-stent electrode previously studied. In this case, the electrode is configured so it can be used as a bipolar electrode, i.e., active and ground electrode are placed in the same device. Besides the results evinced by the obtained results, this kind of electrode avoids eventual skin burns that might occur due to the need of the return electrodes when monopolar electrodes are used.

Due to its good mechanical and biocompatibility characteristics, nitinol SEMS is a popular endoprothesis used for relieving stricture problems in hollow organs due to carcinomas. Besides its mechanical application, SEMS can be regarded as well as potential electrode for performing RF ablation therapy on the tumor. The purpose of this work is to perform numerical and experimental analyses in order to characterize the lesion volume induced in biological tissue using this kind of tubular electrode.

Data concerning electrical conductivity and dimension of the damaged tissue after RF ablation procedure were obtained from ex vivo samples. Next, numerical models using 3D finite element method were obtained reassembling the conditions considered at experimentation setup and results were compared.

Numerical and experimental results show that a regular volume of damaged tissue can be obtained considering this type of electrode. Also, results obtained from numerical simulation are close to those obtained by experimentation.

SEMSs, commonly used as devices to minimize obstruction problems due to the growth of tumors, may still be considered as an active electrode for RF ablation procedures. A method considering this observation is presented in this paper. Also, numerical simulation can be regarded in this case as a tool for determining the lesion volume.

Cholangiocarcinoma is an adenocarcinoma of the bile ducts which drain bile from the liver into the small intestine. Unfortunately, most patients are diagnosed at an advanced stage of the disease with almost no chances for surgery, the only potentially curative treatment. As nitinol stents can be used to reduce stricture problems of the bile duct, these can be also considered as potential electrodes for hyperthermia treatments. Previous works show that, in fact, these metallic stents might be used as part of a feasible solution for delivering radiofrequency (RF) energy into a tumor located in a hollow organ to destroy the tumor tissue. However, the tissue lesion induced is not completely uniform due to convective heat transfer associated to the blood flow in the nearby vessels. The purpose of this paper is to study the use of saline solution for modifying the electrical conductivity of the tissue in order to obtain a more uniform lesion.

A numerical analysis using finite element method on a simplified model of the porta hepatis is performed. The tumor tissue is divided in three sections and simulations were performed considering a higher electrical conductivity in the middle section of the tumor, imitating the presence of a saline solution in this part of the tissue.

Results show that it is possible to obtain a more regular volume, by the way the tumor tissue is preferentially heated, although there are still some risks on exceeding the dimension of the bile duct.

This study presents the numerical analysis of a saline‐enhanced RF tissue thermoablation of a cholangiocarcinoma considering a stent‐based electrode. Results point to the possibility of obtaining a more regular volume of damaged tissue in order to heat and preferentially destroy the tumor tissue.

This paper aims to present a software application, called EasyMAG, for simulating and calculating the magnetic field during the design of domestic/industrial electrical installations.

From a CAD software 3D representation of the model, including the electric wiring and considering the current in the electrical circuits, the software evaluates the magnetic field intensity for power‐line frequencies at different heights.

Two application examples are presented consisting of a cabling layout in a lab room with three phase illumination and power socket circuits and a computer room above a power transformer room. The results were compared with measured values showing a good agreement between them.

Shows that with this software it is possible to anticipate areas where magnetic field values might reach abnormally high values and to analyze alternative wiring layouts in order to keep the magnetic field values as low as possible.

The purpose of this paper is to investigate how the context of open innovation offered by accelerators can affect the successful growth of start-ups. The authors explore accelerators practices and tools in sustaining start-ups and increasing survival probability in their innovation process, with the aim of addressing the following research question: how can start-ups benefit from participation in an accelerator programme from an open innovation perspective?

A review of the literature on start-up successes and failures and on major practices in the open innovation paradigm was carried out, delineating them in the context of accelerators. Given the absence of literature on accelerator practices for supporting start-ups, and aiming at a comprehensive understanding of how the open environment within the accelerator influences a start-up’s survival (or even success) by mitigating the probability of failure, the authors conducted an exploratory case study in an English accelerator.

The open innovation practices mediated by an accelerator and the ones that are not covered, but that can benefit a start-up’s survival, are shown. On the one hand, main effective practices, such as dyadic co-creation with accelerator network partners and crowdsourcing, are revealed to address mostly the lack of, or wrong direction in, product, marketing and relative managerial abilities, which are not usually owned by a start-up due to its “newness”. On the other hand, some causes of failures, such as the intrinsic characteristics of founder teams, do not seem to be addressed by an open approach and neither does participation in an accelerator programme.

This paper is the first to study and link the literature on accelerators, start-ups and open innovation.

The purpose of this paper is to identify the factors that are likely to predict the likelihood of a small firm choosing to participate in formal training programmes. The objective is to inform public policy and practice with regard to what SMEs must do in order to realise the benefits of participating in formal training programmes like their counterpart large firms so as to remain competitive.

The study uses a logistic regression model to ascertain the critical factors that are likely to predict SMEs’ chances to engage in formal training programmes. The data that inform the logit model are based on a non-probability sample of 85 SMEs drawn from Accra, the capital of Ghana.

The major findings are that firm size and having younger owner-managers that are daring play a critical role regarding whether or not small firms in Ghana will offer themselves for formal training programmes. However, firm size, including having young and daring owner-managers reflect the internal resource capacity of a firm. The results imply that the internal resource capacity of a firm is critical in predicting whether or not a small firm will offer itself for a formal training programme, although the changing trends from the external environment are also crucial.

As a result of the lack of an available sample frame, the study is based on a non-probability sample and so it must be noted that the results must be interpreted in that context. Besides, the study sampled SMEs located in Accra, the capital of Ghana, thus future research must extend the study to cover the rest of the nine regions in Ghana. A further analysis based on probability sampling is needed to strengthen the results.

Consequently for the growth and the development of SMEs in developing countries, the need for owner-managers to first focus on internal resource building is key. What this means is that owner-managers cannot ignore the conscious attempt to monitor, develop and grow their own internal resource strengths before that can be aligned to any changing trends from the outside environment.

The paper provides evidence as regards why most SMEs worldwide find it difficult to participate in formal training programmes. The findings seek to enhance the understanding of the barriers to the growth of SMEs’ line of research.

Organic food has additional quality attributes compared to those found in conventional food, such as environmental responsibility and health benefits. Information about these attributes is scarce and complex, the assortment of organic foods is deficient and there are fewer places that sell this kind of food. These factors increase the uncertainty and the transaction costs (TCs) for potential organic fresh fruit and vegetable (FFV) consumers. This paper aims to show the influence of these costs on the intensity of organic FFV consumption, particularly among high-income consumers.

The empirical strategy was based on a survey, and data were collected by administering a structured online questionnaire among residents of the Brazilian Federal District. Organic food consumption was decomposed into three different intensity categories. Data analysis was based on two logistic models, a multinomial regression and an ordered regression, where perceived economic value and different dimensions of TCs were the main independent variables, and the intensity of organic food consumption was the dependent variable.

The results show that organic food consumers are not a homogeneous group, and that perceived economic value and the TCs associated with searching for marketplaces, inadequate product assortment and distrust in health benefits and in organic authenticity are important inhibitors of organic FFV consumption and help explain the intensity of consumption.

This study innovates, as it takes a post-purchase approach, examines different groups based on the intensity of their consumption of organic FFV and focuses on perceived economic value and TCs as important explanations of the intensity of organic FFV consumption.

This paper aims to develop and empirically test a framework on how personal values and sustainability conceptions affect students’ sustainability management orientation (SMO). An understanding of this connection gives insight into the question whether students are likely to engage in sustainable business practices in their future work.

A cross-sectional and comparative research design is used, using survey data of business students from Germany, Indonesia and the USA (N = 475). The proposed mediation models are tested by bootstrap procedures using Hayes’s (2013) PROCESS macro for SPSS.

Self-transcendence values translate into more nuanced sustainability conceptions since individuals with self-transcendence values are more likely to conceptualize sustainability beyond their own (narrow) self-interests. In turn, the stronger individuals’ sustainability conceptions, the higher the likelihood that they prefer sustainable management practices in their future professional working field.

Implications arise for researchers to investigate the engagement of future managers with different personal value types in sustainability practices and to gain insights into values and sustainability conceptions as a learning outcome. Limitations of this research – for instance, arising from potential common method bias – are discussed.

The findings point to the need to (re-)design appointment processes for management positions in a way that allows taking into account individuals’ personal values and sustainability conceptions. This research may also help firms and higher education institutions to empower their workforce/students to develop more integrated perspectives on sustainability challenges as well as teaching methods that address students’ effective learning outcomes, e.g. their values.

The paper offers a new framework and a cross-country perspective on psychological antecedents of individuals’ SMO as an important prerequisite for responsible behavior in the business context.

The purpose of this paper is to develop a performance evaluation model for the operations of the supply chain of an organization of the refrigeration equipment sector. The tool must aid the decision maker in the performance improvement and creation of competitive advantages.

The study adopts a mixture of qualitative and quantitative approaches and applies them through a case study. The data collection was conducted through unstructured interviews and supplemented by documentary research. The applied intervention instrument is the Multicriteria Decision Aid – Constructivist (MCDA-C).

Identification, organization, ordinal and cardinal measurement and integration of the aspects of the context judged as relevant by the decision maker. In addition, it can be highlighted the current situation diagnosis and elaboration of improvement actions related to lean philosophy and advanced planning systems.

The developed model is being used to aid the decision maker in their decisions concerning the improvement of the supply chain operations.

The main contributions made by the paper resides in the proposal of solutions for fulfiling gaps identified within the supply chain performance evaluation area and in the application of the MCDA-C to a practical case.

Performance, Supply chain, Multicriteria, Decision, MCDA-C

Case study

Objetivo

El objetivo de este artículo es desarrollar un Modelo de Desempeño para las operaciones de cadena de suministro de una organización en el sector de equipos de refrigeración. La herramienta debe ayudar a quién toma las decisiones en mejorar el desempeño y crear ventajas competitivas.

El estudio usa una combinación de enfoques cualitativos y cuantitativos aplicándolos a un caso estudio. La recolección de datos se hizo a través de entrevistas no estructuradas y se complementó con investigación documental. El instrumento de intervención usado es el Multicriterio De Apoyo a la Decisión-Constructivista (MCDA-C).

Identificación, organización, mediciones ordinales y cardinales e integración de los aspectos de los contextos considerados como relevantes por el tomador de decisiones. Se puede destacar además la situación actual de diagnóstico y la elaboración de acciones de mejoramiento relacionados con la filosofía Lean y los Sistemas avanzados de planificación.

El modelo desarrollado esta siendo usado para ayudar al toma decisiones en las decisiones concernientes con el mejoramiento de las operaciones de la cadena de suministro.

La mayor contribución hecha por este artículo reside en proponer soluciones para cubrir brechas identificadas dentro el área de Evaluación de Rendimiento en la Cadena de Suministro y en la aplicación del MCDA-C a un caso práctico.

Desempeño, Cadena de Suministro, Decisión, Multicriterio, MCDA-C

estudio de caso

Objetivo

O objetivo de este artigo é desenvolver um Modelo de Avaliação Desempenho para as operações da cadeia de suprimentos de uma organização do setor de equipamentos de refrigeração. O modelo proposto deve ajudar o tomador de decisões a melhorar o desempenho e criar vantagens competitivas.

O estudo faz uso de uma abordagem qualitativa e quantitativa aplicada em um Estudo de Caso. A coleta dos dados foi feita por meio de entrevistas abertas, sendo complementada por pesquisa documental. O instrumento de intervenção usado é o Multicriteria Decision Aid – Constructivist (MCDA-C).

Identificação, organização, medições ordinais e cardinais, e integração dos aspectos do contexto são considerados como relevantes para o tomador de decisões. Além disso, destacam-se o diagnóstico da situação atual e a elaboração de ações de aperfeiçoamento, nas quais se avaliam os efeitos da implementação da Filosofia Enxuta e de um Sistema de Planejamento Avançado na organização.

O modelo desenvolvido auxilia o tomador de decisões nas decisões concernentes ao melhoramento das operações da cadeia de suprimentos.

As principais contribuições do artigo residem na proposição de melhorias em lacunas ainda presentes na avaliação do desempenho da cadeia de suprimentos e também na aplicação da MCDA-C em um caso prático.

Desempenho, Cadeia de Suprimentos, MCDA-C, Decisão, Multicritério

estudo de caso

The purpose of this study sets out to examine (1) how have conflicts been conceptualized and operationalized within the context of online consumption communities? (2) what are the main conflict management, resolution strategies and frameworks that have been identified? and (3) what are the gaps in the relevant body of work in terms of theoretical and methodological dimensions, and what implications do they have for future research.

This study adopts a systematic and multidisciplinary literature review of online conflicts. Following a descriptive and thematic content analysis, it examines 79 peer-reviewed scholarly articles of the past 20 years within 6 scientific databases.

The authors propose a literature-based conceptualization of online conflicts and a multi-level conflict resolution matrix based on the different governance structures and social control mechanisms investigated in extant research.

The originality of this study lies in the integrative and interdisciplinary view of online conflict in global consumption communities.