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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.

We initiated a conversation between two prominent scholars in the field of employee mobility who come from different disciplinary backgrounds: Rajshree Agarwal (from the human capital research tradition) and Matthew Bidwell (from the human resource management research tradition). Their cumulative work leads to vastly different conclusions. In this chapter we had an opportunity to explore their differences and share the roots of their motivations, interests, and research philosophies. The discussion provides diverging, yet insightful, directions for future research.

This chapter is concerned with academic citizenry in higher education, and the conditions created within institutions for transformative leadership. This is central to the fitness-for-purpose of higher education institutions to drive the 2030 Agenda for Sustainable Development.

Drawing from a mixed-method study, the chapter explores the patterns which emerged from literature, questionnaire responses, and semi-structured interviews about the problematics at play within six institutions in the post-colonial contexts of India and South Africa. The two upper middle-income contexts have strong constitutional commitments to democracy and social justice at the macro-level, with bold policy interventions undertaken at meso-level to address the legacies of exclusion and oppression in student enrollment and staff composition in HE. However, recent fraught dynamics and unrest within the sector in each country have brought renewed attention to the politics of participation and a breakdown in trust of governance and management.

In this study, the standpoint of key stakeholders was prioritized, including those in assigned leadership positions and academic staff. Particular attention was paid to gender and intersectional inequalities, impacting academic staff, and what they revealed about the persistence of policy-implementation gaps and their relation to principle-implementation gaps. Concerns are raised about impoverished comprehensions of, and conditions for, sustainable ethical leadership which emerged across both contexts.

Real options theory begins by drawing an analogy between real options and financial options. A financial option is a derivative security whose value is derived from the worth and characteristics of another financial security, or the so-called underlying asset. By definition, a financial option gives its holder the right, but not the obligation, to buy or sell the underlying asset at a specified price (i.e., the exercise price) on or before a given date (i.e., the expiration date). Financial economists Black and Scholes (1973) and Merton (1973) pioneered a formula for the valuation of a financial option, and their methodology has opened up the subsequent research on the pricing of financial assets and paved the way for the development of real options theory.

This paper proposes that patents are real options that allow holders of patents the right but not the obligation to sue others. We suggest that the likelihood of a patent being litigated is positively associated with value of the patent and the extent of disclosure (prior art cited) in the patent. However, under conditions of greater value, increases in disclosure reduce the likelihood of litigation of the focal patent. Similarly, under conditions of greater disclosure, increases in value reduce the likelihood of litigation of the focal patent. Rare events logit analyses of business method patents that were litigated, compared to patents that were not litigated, offer empirical evidence supporting the hypotheses.