Hemodynamic responses to low-level transcutaneous auricular nerve stimulation in young volunteers.

Objectives: The aim of this study was to characterize cardiovascular autonomic responses during two constant current intensities below sensory threshold of transcutaneous auricular nerve stimulation (taNS). On this basis, a protocol for taNS with autonomic modulatory potential could be proposed.

Subjects And Methods: We included 26 men and 24 women, mean age 26.

Cardiovascular responses to low-level transcutaneous vagus nerve stimulation.

Aims: The aim was to determine cardiovascular responses to an arbitrary protocol of transcutaneous low-level vagus nerve electrical stimulation (tVNS).

Methods: Study was performed in 15 male volunteers, mean age 23 years. Data were collected during two sessions - sham stimulation (no stimulation) and stimulation.

A model for potential non-contact ski injuries of the knee.

Broadly accepted is that most knee injuries result from increased vertical forces, usually induced by an incidental ski fall, collision, or a high jump. We present a new non-contact knee injury mechanism that can happen during a ski turn. Such an injury is governed by a sudden inward turn of the inner ski and consequent swing of the inner leg followed by a nearly instant stop when locked by hip and knee joints.

Framework for Personalized Real-Time Control of Hidden Temperature Variables in Therapeutic Knee Cooling.

The paper formalizes, implements and evaluates a framework for personalized real-time control of inner knee temperature during cryotherapy after knee surgery. Studies have shown that the cryotherapy should be controlled depending on the individual patient's feedback on the cooling, which raises the need for smart personalized therapy. The framework is based on the feedback control loop that uses predicted instead of measured inner temperatures because measurements are not feasible or would introduce invasiveness into the system.

Medical-Grade ECG Sensor for Long-Term Monitoring.

The recent trend in electrocardiogram (ECG) device development is towards wireless body sensors applied for patient monitoring. The ultimate goal is to develop a multi-functional body sensor that will provide synchronized vital bio-signs of the monitored user. In this paper, we present an ECG sensor for long-term monitoring, which measures the surface potential difference between proximal electrodes near the heart, called differential ECG lead or differential lead, in short.

Cardiac autonomic regulation and PR interval determination for enhanced atrial fibrillation risk prediction after cardiac surgery.

Background: Changes in cardiac autonomic regulation and P-wave characteristics are associated with the occurrence of atrial fibrillation. The purpose of this study was to evaluate whether combined preoperative non-invasive determination of cardiac autonomic regulation and PR interval allows for the identification of patients at risk of new-onset atrial fibrillation after cardiac surgery.

Methods: RR, PR and QT intervals, and linear and non-linear heart rate variability parameters from 20 min high-resolution electrocardiographic recordings were determined one day before surgery in 150 patients on chronic beta blockers undergoing elective coronary artery bypass grafting, aortic valve replacement, or both, electively.

Continuous remote monitoring of COPD patients-justification and explanation of the requirements and a survey of the available technologies.

Remote patient monitoring should reduce mortality rates, improve care, and reduce costs. We present an overview of the available technologies for the remote monitoring of chronic obstructive pulmonary disease (COPD) patients, together with the most important medical information regarding COPD in a language that is adapted for engineers. Our aim is to bridge the gap between the technical and medical worlds and to facilitate and motivate future research in the field.

On the Convergence of Stresses in Fretting Fatigue.

Fretting is a phenomenon that occurs at the contacts of surfaces that are subjected to oscillatory relative movement of small amplitudes. Depending on service conditions, fretting may significantly reduce the service life of a component due to fretting fatigue. In this regard, the analysis of stresses at contact is of great importance for predicting the lifetime of components.

Cardiovagal and adrenergic function tests in unilateral carotid artery stenosis patients-a Valsalva manoeuvre tool to show an autonomic dysfunction?

Background: The stability of an arterial baroreflex depends also upon the integrity of the afferent limb. For its quantification, we can use a noninvasive test such as baroreceptor sensitivity estimation during Valsalva manoeuvre. The aim of this study was to evaluate potential autonomic dysfunction in patients with unilateral severe carotid disease and compare the results to the results obtained from an age and gender matched group of healthy volunteers.

Simple cardiovagal and adrenergic function tests in carotid artery stenosis patients as a potential tool for determining a transient autonomic dysfunction.

Purpose: The arterial baroreflex depends on the integrity of the afferent limb, which can be quantified using the baroreceptor's sensitivity (BRS) during the Valsalva maneuver (VM). The aim of this study was to evaluate, using autonomic nervous system tests, the autonomic function in patients after a carotid artery angioplasty (CAS).

Methods: We evaluated the changes in blood pressure (BP) during the VM (Valsalva ratio, BRS, sympathetic indexes) in 41 patients with symptomatic, unilateral, internal carotid artery stenosis.

Non-invasive real-time prediction of inner knee temperatures during therapeutic cooling.

The paper addresses the issue of non-invasive real-time prediction of hidden inner body temperature variables during therapeutic cooling or heating and proposes a solution that uses computer simulations and machine learning. The proposed approach is applied on a real-world problem in the domain of biomedicine - prediction of inner knee temperatures during therapeutic cooling (cryotherapy) after anterior cruciate ligament (ACL) reconstructive surgery. A validated simulation model of the cryotherapeutic treatment is used to generate a substantial amount of diverse data from different simulation scenarios.

Smart wireless sensor for physiological monitoring.

Presented is a wireless body sensor capable of measuring local potential differences on a body surface. By using on-sensor signal processing capabilities, and developed algorithms for off-line signal processing on a personal computing device, it is possible to record single channel ECG, heart rate, breathing rate, EMG, and when three sensors are applied, even the 12-lead ECG. The sensor is portable, unobtrusive, and suitable for both inpatient and outpatient monitoring.

Exact parallel maximum clique algorithm for general and protein graphs.

A new exact parallel maximum clique algorithm MaxCliquePara, which finds the maximum clique (the fully connected subgraph) in undirected general and protein graphs, is presented. First, a new branch and bound algorithm for finding a maximum clique on a single computer core, which builds on ideas presented in two published state of the art sequential algorithms is implemented. The new sequential MaxCliqueSeq algorithm is faster than the reference algorithms on both DIMACS benchmark graphs as well as on protein-derived product graphs used for protein structural comparisons.

Estimating the Universal Positions of Wireless Body Electrodes for Measuring Cardiac Electrical Activity.

A methodology is presented for estimating the wireless body electrode (WE) positions and for calculating the linear transformations that enable the synthesis of a 12-lead ECG or a multichannel ECG from three WEs, which in turn simplifies and improves the acquisition of ECGs. We present, compare, and evaluate three approaches to the synthesis: fully personalized, fully universal, and combined with universal leads and personalized transformations. The evaluation results show that WEs are an acceptable alternative to the standard 12-lead ECG device for patients with chronic myocardial ischemia, if either the fully personalized or combined approach is used.

Knee temperatures measured in vivo after arthroscopic ACL reconstruction followed by cryotherapy with gel-packs or computer controlled heat extraction.

Purpose: To obtain in vivo data about intra- and extra-articular knee temperatures to assess the effectiveness of two cryotherapeutic methods-conventional cooling with gel-packs and computer controlled cryotherapy following anterior cruciate ligament (ACL) reconstructive surgery.

Methods: Twenty patients were arbitrarily assigned for cryotherapy after ACL reconstruction: 8 patients with frozen gel-packs and 12 patients with computer controlled cryotherapy with constant temperatures of the cooling liquid in the knee pads. The treatment was performed for 12 h.

Electrocardiographic systems with reduced numbers of leads-synthesis of the 12-lead ECG.

Systems with reduced numbers of leads that can synthesize the 12-lead electrocardiogram (ECG) with an insignificant or a small loss of diagnostic information have been proposed. The advantage over standard 12-lead ECG systems is the smaller number of measurement sites (i.e.

Two proximal skin electrodes--a respiration rate body sensor.

We propose a new body sensor for extracting the respiration rate based on the amplitude changes in the body surface potential differences between two proximal body electrodes. The sensor could be designed as a plaster-like reusable unit that can be easily fixed onto the surface of the body. It could be equipped either with a sufficiently large memory for storing the measured data or with a low-power radio system that can transmit the measured data to a gateway for further processing.

Parallel-ProBiS: fast parallel algorithm for local structural comparison of protein structures and binding sites.

The ProBiS algorithm performs a local structural comparison of the query protein surface against the nonredundant database of protein structures. It finds proteins that have binding sites in common with the query protein. Here, we present a new parallelized algorithm, Parallel-ProBiS, for detecting similar binding sites on clusters of computers.

Asynchronous master-slave parallelization of differential evolution for multi-objective optimization.

In this paper, we present AMS-DEMO, an asynchronous master-slave implementation of DEMO, an evolutionary algorithm for multi-objective optimization. AMS-DEMO was designed for solving time-intensive problems efficiently on both homogeneous and heterogeneous parallel computer architectures. The algorithm is used as a test case for the asynchronous master-slave parallelization of multi-objective optimization that has not yet been thoroughly investigated.

Simulated temperature distribution of the proximal forearm.

Temperature changes in the resting proximal human forearm have been studied non-invasively, using computer simulation. A procedure for spatial model generation, based on digitized slice data, has been applied. A mathematical model and a 3-D computer simulation program have been implemented.

Synthesis of the 12-lead electrocardiogram from differential leads.

A new approach is proposed for synthesizing the standard 12-lead ECG from three differential leads formed by pairs of proximal electrodes on the body surface. The method is supported by a statistical analysis that gives the best personalized positions of electrodes. The measurements from multichannel ECGs were used to calculate the differential leads.

Computer simulation of topical knee cooling.

Local topical cooling with gel-packs or cryo-cuffs is often used after surgery or after knee injuries. Mostly beneficial, but some deleterious effects have been reported in literature. The spatial distribution of heat/cold through different tissues of the knee in time may be responsible for different effects of cooling on the traumatized or inflamed tissue and have yet to be studied.

Ventricular repolarization dynamicity and arrhythmic disturbances after beating-heart and arrested-heart revascularization.

Background: Arrhythmias attributable to altered autonomic modulation of the heart, with elevated sympathetic and depressed vagal modulation, occur to a similar extent after surgery performed on beating or arrested hearts. Coronary artery bypass grafting (CABG) with cardiopulmonary bypass has been associated with more frequent occurrence of arrhythmic events than surgery performed without CABG, even with comparable levels of postoperative cardiac autonomic (dis) regulation after arrested- and beating-heart revascularization. We explored the effects of arrested- and beating-heart revascularization procedures on the dynamics of ventricular repolarization and on increased postoperative arrhythmic events.

Computer-simulated alternative modes of U-wave genesis.

Objective: Several hypotheses for the origin of the U wave in electrocardiograms have been proposed. We have set out to explore and test alternative modes for U-wave genesis via computer simulations.

Methods And Results: A spatial model of a left ventricle has been constructed from 12 layers composed of cubic cells.