de Novo Radio Frequency Ablation Therapy: Application of Unexplored Electromagnetic Spectral Resources of mm-Wave/THz Band in Clinical Ablation Procedures - A Review

Review Focus: General considerations on ablation procedure advocated in clinical contexts using electromagnetic (EM) energy are comprehensively reviewed. Relevant radiofrequency (RF) and/or microwave ablation techniques that have been in vogue and in traditional use across clinical procedures are revisited. Traditionally, RF/microwave ablations have been applied to a variety of pathological states, (in lieu of surgical methods and/or electrocautry procedures) so as to remove unwanted/cancerous tissue layers. Relevantly, new avenues of adopting unexplored electromagnetic (EM) energy falling in the spectral range of mm-wave/THz frequencies for such medical ablation purposes are studied. These higher frequencies for ablation can be considered either to supplant or used in parallel with the existing RF/microwave bands (at 915 MHz and 2.45 GHz). The motivation thereof is to identify certain improved ablation feasibility and derivable merits in clinical sense. Hence, the efficacy of the proposed scheme is identified for two exemplar ablation therapy procedures pertinent to Barrett’s esophagus and menorrhagia. Pertinent pros and cons are discussed and practical ablator designs are indicated. Study Details: Considering the strategy of using the proposed mm-wave/THz EM energy would amount to a shallow ablation via ‘thermal scouring’ of the tissue-linings intended for ablation and prevent otherwise undesirable hot-spots in deep-tissue media. This is conceivable because the advocated frequency bands would allow a very shallow skin-depth of penetration of EM energy; and hence, tissue-heating will be limited only to superficial linings. Further, the associated super-high frequency will heat the ablation site extremely fast reducing the procedure time considerably. In a Nut-shell: The study first offers a comprehensive review on classical and projects de novo aspects of EM ablation therapy with unexplored electromagnetic spectral resources of mm-Wave/THz band. Illustrated as examples are feasibility details concerning the ablation of the endometrium and Barrett’s esophagus. Design aspects of ablators are presented. Place and Duration of Study: The study reported is limited to a review on the subjectmatter and provides analytical designs and computational models on the procedure performed (2012-2013) at: Department of Computer and Electrical Engineering and Computer Science, College of Engineering & Computer Science, Florida Atlantic University, Boca Raton, Florida 33431, USA

A Microwave Gaussian-Beam Launcher With An Active Aperture-Blockage To Control The Spot-Size Of The Beam

A method of controlling the spot-size of a focused microwave Gaussian-beam using an active aperture-blockage is described. The Gaussian-beam launcher consists of an open-ended scalar-horn with a dielectric hyperhemisphere at its aperture. Also included is an AgI-pellet at the aperture-center with a provision to heat it with an external dc source. The scalar-horn plus the dielectric lens launch a Gaussian-beam; and, the AgI pellet when heated, becomes a superionic conductor offering an aperture-blockage. This results in a variation of the spot-size of the emergent-beam. Theoretical results and experimental data are furnished and compared. © 1994 IEE

Constructive ANN with Dynamically Set Sigmoid: A Simulation Tool for Technoeconomic Forecasting

To forecast future outcomes in an economic growth scenario, a novel and compatible version of an artificial neural network (ANN) is developed. It is designed with a dynamic sigmoidal (squashing) function that morphs to the stochastical trends of the ANN input. Relevant network architecture then gets pruned for reduced complexity across the span of iterative training schedule leading to the realisation of a constructive artificial neural-network (CANN). In the associated operation, the input-output relation in the network is set to change dynamically by varying the initial slope of the intervening squashing function (sigmoid) during the training phase. This slope-changing is realised by choosing the so-called Langevin-Bernoulli function (LBF) as the sigmoid, (in lieu of traditional hyperbolic tangent function). By changing the associated order-parameter, the initial slope of LBF is altered enabling an eventual reduced network complexity. A CANN designed with above features is used to track the temporal evolution of an entity (such as an economic parameter); and, it is adopted to forecast future trends of technoeconomic evolution with minimal under- or over-fitted predictions. The conceived method is applied to an available set of technoeconomic data and the efficacy of forecasting is ascertained thereof

An ex ante forecast on economically engineered bit rates for IPTV service via xDSL transports of internodal access

IPTV, xDSL economically engineered bit rates, Bit rate forecast,