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Biological oscillatory activity in neural networks has been intensively studied over the past years. Neuronal oscillations are the basis of many different behavioral patterns and sensory mechanism. Understanding the dynamic properties of these mechanisms is useful for analyses of biological functions and medical diagnoses. The dynamic characteristics of wake‐sleep circadian rhythms and ECG’s cardiac cycle data measured for normal subjects are identified here, using MA‐BP neural network model. It was found that dynamics of regular components can be captured by the model. The captured dynamics are kept in a steady state for some periods. The order of the MA neural network was suppressively controlled by the first 2∼3 orders. Hence it may be useful for medical diagnoses of circadian rhythms and heart related diseases.

The purpose of this work is to perform an application study on experimental animals (dogs) to investigate the efficiency of using weft knitted mesh fabric as cardiac support mesh to support left ventricular hypertrophy.

In this work, weft-knitted mesh sample “Knitted Cardiac Support Mesh” manufactured using Nylon (6, 6) yarns, with count 20 Denier and medium mesh size, was placed around the two ventricles to prevent further dilatation, support and reduce left ventricular wall stress.

Medical textile is a rapidly expanding field in technical textiles that are widely used in a variety of medical applications. One of these medical textile applications is “Knitted Cardiac Support Mesh”, which is used in the treatment of Dilated Cardiomyopathy.

After the implantation of the manufactured Knitted Cardiac Support Mesh around the myocardium, all dogs survived for three months before being euthanized, and some clinical examinations were performed to investigate and evaluate the sample performance. It was demonstrated from the experimental application, that the nylon mesh sample performed the best during the surgical operation due to its good ability to stretch and recover at a moderate rate, as well as the textile mesh lightweight.

The purpose of this paper is to review the Braidwood Commission's two reports on the use of TASER conducted energy weapons in Canada and the death of Robert Dziekanski to determine whether the Commission's conclusions and subsequent recommendations constitute sound evidence‐based public policy.

This study analyzes Commissioner Braidwood's eight findings from the first report regarding the medical implications of the use of TASER devices by comparing those findings to the body of scientific, medical, and technical literature on the physiological effects of TASER technology. Additionally, this study reviews the potential ramifications of the Commissioner's recommendations regarding the use of TASER devices in both reports.

Evidence from the existing literature does not support the Commission's findings regarding the medical risks of the use of TASER technology. Recommendations to restrict the use of TASER devices are unlikely to reduce arrest‐related deaths, but they are likely to result in increased injuries to officers and suspects. Other recommendations, including training standards, testing requirements, reporting requirements, medical assistance, and research and review, are consistent with other reviews on the use of TASER technology and are necessary and appropriate to restore public confidence in police use‐of‐force.

The Braidwood Commission recommendations have had an immediate impact on the policies of several police agencies in Canada, including the Royal Canadian Mounted Police, but this study is the first critically to review whether those recommendations constitute formulation of sound evidence‐based public policy.

Less lethal weapons have become a critical tool for law enforcement when confronting dangerous, combative individuals in the field. The purpose of this paper is to review the medical aspects and implications of three different types of less lethal weapons.

The paper conducted a comprehensive medical literature review on blunt projectiles, irritant sprays including oleoresin capsicum (OC), and conducted energy devices such as the Taser™. It reviews the history, mechanisms of action, intended and other physiologic effects, and medical safety risks and precautions of these devices. In particular, the paper focuses on the issue of sudden in‐custody death and less lethal weapons, reviewing case reports, animal research and human investigative studies on this topic.

In general, these three different types of less lethal weapons have been effective for their intended use. Each type of less lethal weapon has a number of physiologic effects and specific medical issues that must be considered when the weapon is used. There is no clear evidence that these devices are inherently lethal, nor is there good evidence to suggest a causal link between sudden in‐custody death and the use of irritant sprays or conducted energy devices.

While further research on the physiologic effects of these devices is needed, this paper provides law enforcement with a medical review of less lethal weapons including blunt projectiles, irritant sprays such as OC, and conducted energy devices such as the Taser.

The purpose of this paper is to describe a numerical inversion technology developed to reconstruct endocardial electric potential maps on the internal surface of heart chambers utilizing intracavitary multi‐electrode catheter measurements. The objective is to perform the reconstruction real time with high accuracy, thereby allowing the incorporation of the technology into medical imaging systems.

Electrode potential points from several beats are merged in order to maximize the information extracted from the catheter measurements. To solve the ill‐posed inverse problem fast, numerically stable solution algorithms based on generalized Tikhonov regularization and bidiagonalization are developed. The latter algorithm also provides an efficient framework for choosing the regularization parameter optimally.

Results of three examples are presented to thoroughly illustrate the performance of the algorithm: one with synthetic data generated in a computational electromagnetics (virtual lab) environment, thereby allowing exact error analysis; another with measured data from a phantom‐bench human heart model where the effect of measurement errors can be investigated in a controlled environment; and a third example that illustrates how the algorithm performs when the catheter data are collected in vivo in a swine heart.

The speed and accuracy in the three examples successfully prove that the inversion technology can be a key component of medical imaging systems.

While some elements of these computational models and techniques presented have been used for decades, the authors achieve speed and accuracy that have not been reported before by combining multi‐beat catheter measurements, the generalized Tikhonov regularization technique, a bidiagonalization algorithm and other top‐notch linear algebra techniques.

Cardiac function generally deteriorates with increasing age, although recent research has found a reversal in this decline in a group of middle‐aged individuals after 18 weeks of brisk walking in single daily bouts of between 20‐40 minutes. Government guidelines advocate accumulative short bouts of exercise for the promotion of health. The purpose of this study was to determine whether accumulative short walking bouts were as effective at producing changes in cardiac function as those previously found from single daily bouts. Presents the results of post‐intervention ANCOVA statistical analysis of 64 healthy men and women, aged 40‐68 years, who were not habitual exercisers, who were randomly divided into matched groups of either short walkers or controls who were also not habitual exercisers.

Predictive models implemented in medical procedures can potentially bring great benefit to patients and represent a step forward in targeted treatments based on a patient’s physiological condition. It is the purpose of this paper to outline such a model.

A multi-scale 0D-3D model based on patient specific geometry combines a 0-dimensional lumped parameter model (LPM) with a 3D computational fluid dynamics (CFD) analysis coupled in time, to obtain physiologically viable flow parameters.

A comparison of physiological data gathered from literature with flow-field measurements in this model shows the viability of this method in relation to potential predictions of pathological flows repercussions and candidate treatments.

A limitation of the model is the absence of compliance in the walls in the CFD fluid domain; however, compliance of the peripheral vasculature is accounted for by the LPM. Currently, an attempt is in progress to extend this multi-scale model to account for the fluid-structure interaction of the ventricular assist device vasculature and hemodynamics.

This work reports on a predictive pulsatile flow model that can be used to investigate surgical alternatives to reduce strokes in LVADs.

This study aims to perform three-dimensional numerical computations for blood flow through a double stenosed carotid artery. Pulsatile flow with Womersley number (Wo) of 4.65 and Reynolds number (Re) of 425, based on the diameter of normal artery and average velocity of inlet pulse, was considered.

Finite volume method based ANSYS Fluent 20.1 was used for solving the governing equations of three-dimensional, laminar, incompressible and non-Newtonian blood flow. A high-quality grid with sufficient refinement was generated using ICEM CFD 20.1. The time-averaged flow field was captured to investigate the effect of severity and eccentricity on the lumen flow characteristics.

The results show that an increase in interspacing between blockages brings shear layer instability within the region between two blockages. The velocity profile and wall shear stress distribution are found to be majorly influenced by eccentricity. On the other hand, their peak magnitude is found to be primarily influenced by severity. Results have also demonstrated that the presence of eccentricity in stenosis would assist in flow development.

Variation in severity and interspacing was considered with a provision of eccentricity equal to 10% of diameter. Eccentricity refers to the offset between the centreline of stenosis and the centreline of normal artery. For the two blockages, severity values of 40% and 60% based on diameter reduction were permuted, giving rise to four combinations. For each combination, three values of interspacing in the multiples of normal artery diameter (D), viz. 4D, 6D and 8D were considered.

This bibliography is offered as a practical guide to published papers, conference proceedings papers and theses/dissertations on the finite element (FE) and boundary element (BE) applications in different fields of biomechanics between 1976 and 1991. The aim of this paper is to help the users of FE and BE techniques to get better value from a large collection of papers on the subjects. Categories in biomechanics included in this survey are: orthopaedic mechanics, dental mechanics, cardiovascular mechanics, soft tissue mechanics, biological flow, impact injury, and other fields of applications. More than 900 references are listed.

This paper aims to introduce a non-invasive and convenient method to detect a life-threatening disease called aortic dissection. A Bayesian inference based on enhanced multi-sensors impedance cardiography (ICG) method has been applied to classify signals from healthy and sick patients.

A 3D numerical model consisting of simplified organ geometries is used to simulate the electrical impedance changes in the ICG-relevant domain of the human torso. The Bayesian probability theory is used for detecting an aortic dissection, which provides information about the probabilities for both cases, a dissected and a healthy aorta. Thus, the reliability and the uncertainty of the disease identification are found by this method and may indicate further diagnostic clarification.

The Bayesian classification shows that the enhanced multi-sensors ICG is more reliable in detecting aortic dissection than conventional ICG. Bayesian probability theory allows a rigorous quantification of all uncertainties to draw reliable conclusions for the medical treatment of aortic dissection.

This paper presents a non-invasive and reliable method based on a numerical simulation that could be beneficial for the medical management of aortic dissection patients. With this method, clinicians would be able to monitor the patient’s status and make better decisions in the treatment procedure of each patient.