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1 – 10 of 77About 50 epidemiological reports about possible associations between cancer morbidity and exposure to electromagnetic fields (EMFs) were published between 1979 and 1994. The…
Abstract
About 50 epidemiological reports about possible associations between cancer morbidity and exposure to electromagnetic fields (EMFs) were published between 1979 and 1994. The majority of them (60‐75 per cent) documented a slight (1.5 to twofold) but significant increase in the incidence of certain rare forms of neoplasms (leukaemia, lymphoma, brain tumours). A limited support for carcinogenic potencies of EMFs is provided from cellular studies, but the effects appear to be generally weak, transient and difficult to replicate. Concludes that the available evidence associating cancer and EMF exposure is too tenuous to be convincing but too consistent to be ignored. Further progress needs better quantification of exposure levels and conditions, evaluation of dose‐effect relationships and liability to confounding carcinogenic factors that may influence morbidity rates in the investigated populations.
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In the last 100 years mankind has, for the first time in evolution,incorporated artificial electromagnetic fields and radiations into thebuilt environment. Thirty years passed…
Abstract
In the last 100 years mankind has, for the first time in evolution, incorporated artificial electromagnetic fields and radiations into the built environment. Thirty years passed after the discovery of X‐rays before any exposure limits were imposed on these “ionizing” radiations, and the exposure limits have steadily fallen ever since, as early researchers found out to their cost just how dangerous these unseen energies are. Now scientists are asking whether chronic exposure to the non‐ionizing electromagnetic fields ubiquitous in homes, offices and factories, and which also emanate from powerlines, TV and radio masts and radar, are also likely to cause ill health. Sets out the present position in the fierce debate over claimed ill health effects from weak environmental electromagnetic fields, assesses the evidence, and gives practical advice for the structural engineer or surveyor. This is a subject to which professional bodies must give serious consideration within the near future, on the basis of this and other independent advice.
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Luca G. Campana, Paolo Di Barba, Fabrizio Dughiero, Michele Forzan, Maria Evelina Mognaschi, Rudy Rizzo and Elisabetta Sieni
In electrochemotherapy, flexible electrodes, composed by an array of needles, are applied to human tissues to treat large surface tumors. The positioning of the needles in the…
Abstract
Purpose
In electrochemotherapy, flexible electrodes, composed by an array of needles, are applied to human tissues to treat large surface tumors. The positioning of the needles in the tissue depends on the surface curvature. The parallel needle case is preferred, as their relative inclinations strongly affect the actual distribution of electric field. Nevertheless, in some case, small inclinations are unavoidable. The purpose of this paper is to study the electric field distribution for non-parallel needles.
Design/methodology/approach
The effect of electrode position is evaluated systematically by means of numerical models and experiments on phantoms for two different angles (5° and 30°) and compared with the case of parallel needles. Potato model was used as phantom, as this tissue becomes dark after few hours from electroporation. The electroporation degree was gauged from the color changings on the potatoes.
Findings
The distribution of electric field in different needle configuration is found by means of finite element analysis (FEA) and experiments on potatoes. The electric field level of inclined needles was compared with parallel needle case. In particular, the electric field distribution in the case of inclined needles could be very different with respect to the one in the case of parallel needles. The degree of enhancement for different inclinations is visualized by potato color intensity. The FEA suggested that the needle parallelism has to be maintained as possible as if the tips are closer to each other, the electric field intensity could be different with respect to the one in the case of parallel needles.
Originality/value
This paper analyzes the effect of inclined electrodes considering also the non-linearity of tissues.
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H. Brauer, M. Ziolkowski and J. Haueisen
We applied minimum norm estimations using different regularization techniques to the solution of the biomagnetic inverse field problem. Using magnetic field data measured with a…
Abstract
We applied minimum norm estimations using different regularization techniques to the solution of the biomagnetic inverse field problem. Using magnetic field data measured with a multi‐channel‐SQUID‐sensor‐system we computed reconstruction of the impressed current density distributions which were generated by extended current sources placed inside a human torso phantom. The common inverse techniques usually applied in modern biomedical investigations in bioelectricity or biomagnetism are compared, and their aptitude for reconstruction of 3D current sources in space was evaluated. We analyzed the impact of using magnetic data, electrical data, and combination of both respectively on the localization of an equivalent current dipole (ECD). Finally, we use a visualization tool which enables a comparison of current density reconstruction. The study is, in parts, related to the new TEAM problem No. 31.
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Andrzej Krawczyk, Sl§awomir Wiak and Tomasz Zyss
Deals with the problems of interactions between the electromagnetic field and the human brain. In particular, the problem of eddy currents in brain tissue induced for medical…
Abstract
Deals with the problems of interactions between the electromagnetic field and the human brain. In particular, the problem of eddy currents in brain tissue induced for medical purposes is discussed. The mathematical modelling of the phenomenon is presented.
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Antonino Laudani, Salvatore Coco and Francesco Riganti Fulginei
The paper aims to illustrate the two kinds of analysis approach for which finite element method (FEM) can be successfully employed: the Poisson-Nernst-Planck (PNP) model and the…
Abstract
Purpose
The paper aims to illustrate the two kinds of analysis approach for which finite element method (FEM) can be successfully employed: the Poisson-Nernst-Planck (PNP) model and the Langevin-Lorentz-Poisson (LLP) one.
Design/methodology/approach
The approach of this work is to try making a survey of the use of the FEM in the modelling of charge transport/ion flow across membrane channels, in particular for the PNP analysis and for a particle based model such as LLP model.
Findings
In this paper, the two kinds of analysis approach for which FEM can be successfully employed, the PNP model and the LLP one, have been shown. In both cases the FEM is extremely useful to carry out these analysis and the simulation results obtained are in good agreement with experimental results.
Originality/value
The value of this paper is to demonstrate the FEM is extremely useful to carry out analysis and results which are in good agreement with experimental ones.
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Hartmut Brauer, Marek Ziolkowski, Uwe Tenner, Jens Haueisen and Hannes Nowak
Applies four different minimum norm estimations with common regularization techniques, often used in biomedical applications to the solution of the biomagnetic inverse field…
Abstract
Applies four different minimum norm estimations with common regularization techniques, often used in biomedical applications to the solution of the biomagnetic inverse field problem. Magnetic field data measured with a multi‐channel biomagnetometer sensor system in a magnetically shielded room were used to reconstruct the current density distributions generated by an extended current source which was placed inside a human torso phantom. No one of the tested methods is able to estimate the extension of the source. To improve the results as much as possible a priori information of the source space should be taken into account.
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Paolo Di Barba, Fabrizio Dughiero, Michele Forzan and Elisabetta Sieni
This paper aims to present the optimal design of an inductor used to heat a magnetic nanoparticle fluid injected in a cell culture inside a Petri dish.
Abstract
Purpose
This paper aims to present the optimal design of an inductor used to heat a magnetic nanoparticle fluid injected in a cell culture inside a Petri dish.
Design/methodology/approach
The inductor design is driven by means of a multi-objective optimization algorithm that generalizes the migration-non-dominated sorting genetic algorithm (NSGA); it is called self-adapting migration-NSGA.
Findings
The optimized device is able to synthesize a uniform magnetic field in a nanoparticle fluid, substantially helping its heating capability. The ultimate scope is to assist the cancer therapy based on magnetic fluid hyperthermia (MFH).
Originality/value
The optimal design of an inductor for MFH applications has been carried out by applying an improved version of migration-based NSGA-II algorithm including automatic stop and a self-adapting concept. The modified optimization algorithm is suitable to find better optimal solutions with respect to a standard version of NSGA-II.
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Elisabetta Sieni, Paolo Di Barba, Fabrizio Dughiero and Michele Forzan
The purpose of this paper is to present a modified version of the non-dominated sorted genetic algorithm with an application in the design optimization of a power inductor for…
Abstract
Purpose
The purpose of this paper is to present a modified version of the non-dominated sorted genetic algorithm with an application in the design optimization of a power inductor for magneto-fluid hyperthermia (MFH).
Design/methodology/approach
The proposed evolutionary algorithm is a modified version of migration-non-dominated sorting genetic algorithms (M-NSGA) that now includes the self-adaption of migration events- non-dominated sorting genetic algorithms (SA-M-NSGA). Moreover, a criterion based on the evolution of the approximated Pareto front has been activated for the automatic stop of the computation. Numerical experiments have been based on both an analytical benchmark and a real-life case study; the latter, which deals with the design of a class of power inductors for tests of MFH, is characterized by finite element analysis of the magnetic field.
Findings
The SA-M-NSGA substantially varies the genetic heritage of the population during the optimization process and allows for a faster convergence.
Originality/value
The proposed SA-M-NSGA is able to find a wider Pareto front with a computational effort comparable to a standard NSGA-II implementation.
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Michela Montesi and John Mackenzie Owen
The purpose of this paper is to outline how article genres, or article types, are classified and described in the disciplines of biology, education, and software engineering. By…
Abstract
Purpose
The purpose of this paper is to outline how article genres, or article types, are classified and described in the disciplines of biology, education, and software engineering. By using the expression article genres, emphasis is placed on the social role of journal articles that, as such, accomplish specific communicative functions and are intended for a certain context and audience.
Design/methodology/approach
Drawing on this idea, the instructions to authors of the research journals cited in the Journal Citation Reports for each of the three disciplines are analysed.
Findings
The information provided by the instructions to authors of major publications in the fields studied allows one to describe the following article genres: major articles, theoretical articles, review articles, short articles, practice‐oriented articles, case studies, comment and opinion, and reviews.
Research limitations/implications
Results show that article genres reflect the nature of research in each field to the extent that using them to describe items along with topic may improve management and retrieval of scientific documents. In addition, article genres perform specific communicative functions within disciplinary communities, which accounts for both emerging types of articles and variations in traditional types.
Originality/value
The paper summarizes the information on article genres available in the instructions to authors of scientific journals in the disciplines of biology, education and software engineering. It attempts to show how results can mirror the nature of research in each field as well as current debates within each discipline on the state and quality of research. Also it shows how article genres convey specific communication needs within disciplinary communities, which proves that genres are social and evolving objects.
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