Bioimpedance imaging aims to generate a 3D map of the resistivity and permittivity of biological tissue from multiple impedance channels measured with electrodes applied to the skin. When the electrodes are distributed around the body (for example, by delineating a cross section of the chest or a limb), bioimpedance imaging is called electrical impedance tomography (EIT) and results in functional 2D images. Conventional EIT systems rely on individually cabling each electrode to master electronics in a star configuration.
View Article and Find Full Text PDFBackground And Aims: The cell walls of charophytic algae both resemble and differ from those of land plants. Cell walls in early-diverging charophytes (e.g.
View Article and Find Full Text PDFAll land-plant cell walls possess hemicelluloses, cellulose and anionic pectin. The walls of their cousins, the charophytic algae, exhibit some similarities to land plants' but also major differences. Charophyte 'pectins' are extractable by conventional land-plant methods, although they differ significantly in composition.
View Article and Find Full Text PDFIntroduction: Improving patients’ knowledge of diabetes would support adherence to treatment, prevent complications, and promote shared decision-making. Healthcare professionals need to assess patients’ knowledge using a validated questionnaire in the local language.
Objective: The aim of the study was to translate the Diabetes Knowledge Questionnaire from English to French and assess the psychometric properties of the translated version.
Current wearable respiratory monitoring devices provide a basic assessment of the breathing pattern of the examined subjects. More complex monitoring is needed for healthcare applications in patients with lung diseases. A multi-sensor vest allowing continuous lung imaging by electrical impedance tomography (EIT) and auscultation at six chest locations was developed for such advanced application.
View Article and Find Full Text PDFBiopotential imaging (e.g., ECGi, EEGi, EMGi) processes multiple potential signals, each requiring an electrode applied to the body's skin.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
July 2022
Fetal electrocardiography (fECG) has gotten widespread interest in the last years as technology for fetal monitoring. Compared to cardiotocography (CTG), the current state of the art, it can be designed in smaller formfactor and is thus suited for long-term and unsupervised monitoring. In the present study we evaluated a wearable system which is based on CSEM's cooperative sensors, a versatile technology that allows for the measurement of multiple biosignals and an easy integration into a garment or patch.
View Article and Find Full Text PDFLung sounds acquired by stethoscopes are extensively used in diagnosing and differentiating respiratory diseases. Although an extensive know-how has been built to interpret these sounds and identify diseases associated with certain patterns, its effective use is limited to individual experience of practitioners. This user-dependency manifests itself as a factor impeding the digital transformation of this valuable diagnostic tool, which can improve patient outcomes by continuous long-term respiratory monitoring under real-life conditions.
View Article and Find Full Text PDFClassical approaches for measuring high-quality ECG require the use of gel electrodes and individually shielded cables, which limit patient comfort, especially in long-term use. We recently introduced a novel sensing architecture-so-called cooperative sensors-that allow the use of active dry electrodes connected by two unshielded wires. The aim of this work is to qualitatively evaluate an ECG recorded with a dry-electrode cooperative-sensor system.
View Article and Find Full Text PDFObjective: Development of wearable medical technology for remote monitoring of patients suffering from chronic lung diseases may improve the care, therapy and outcome of these patients.
Approach: A multimodal system using wearable sensors for the acquisition of multiple biosignals (electrical bioimpedance of the chest for electrical impedance tomography and respiratory rate assessment, peripheral oxygen saturation, chest sounds, electrocardiography for heart rate measurement, body activity, and posture) was developed and validated in a prospective, monocentric study on 50 healthy subjects. The subjects were studied under different types of ventilation (tidal and deep breathing, forced full expiration maneuver) and during increased body activity and posture changes.
IEEE Trans Biomed Eng
March 2019
This paper presents a wearable sensor architecture for frequency-multiplexed electrical impedance tomography (EIT) and synchronous multilead electrocardiogram (ECG) data acquisition. The system is based on a novel electronic sensing architecture, called cooperative sensors, that significantly reduces the cabling complexity and enables flexible EIT stimulation and measurement patterns. The cooperative-sensor architecture was initially designed for ECG and has been extended for multichannel bioimpedance measurement.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
July 2017
Classical approaches to make high-quality measurements of biopotential signals require the use of shielded or multi-wire cables connecting the electrodes to a central unit in a star arrangement. Consequently, increasing the number of leads increases cabling and connector complexity which is not only limiting patient comfort but also anticipated as the main limiting factor for future miniaturization and cost reduction of tomorrow's wearables. We have recently introduced a novel sensing architecture that significantly reduces cabling complexity by eliminating shielded or multi-wire cables as well as by allowing simple connectors thanks to a bus arrangement.
View Article and Find Full Text PDFIEEE Trans Biomed Eng
January 2018
Classical approaches to make high-quality measurements of biopotential signals require the use of shielded or multiwire cables connecting the electrodes to a central unit in a star arrangement. As a consequence, increasing the number of leads increases cabling and connector complexity, which is not only limiting the patient comfort but is also anticipated as the main limiting factor to future miniaturization and cost reduction of tomorrow's wearables. We have recently introduced a novel sensing architecture that significantly reduces the cabling complexity by eliminating shielded or multiwire cables and by allowing simple connectors, thanks to a bus arrangement.
View Article and Find Full Text PDFBackground: Assessment of pulmonary edema is a key factor in monitoring and guidance of therapy in critically ill patients. To date, methods available at the bedside for estimating the physiologic correlate of pulmonary edema, extravascular lung water, often are unreliable or require invasive measurements. The aim of the present study was to develop a novel approach to reliably assess extravascular lung water by making use of the functional imaging capabilities of electrical impedance tomography.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
October 2016
Cooperative sensors are an emerging technology consisting of autonomous sensor units working in concert to measure physiological signals requiring distant sensing points, such as biopotential (e.g., ECG) or bioimpedance (e.
View Article and Find Full Text PDFElectrical impedance tomography (EIT) allows the measurement of intra-thoracic impedance changes related to cardiovascular activity. As a safe and low-cost imaging modality, EIT is an appealing candidate for non-invasive and continuous haemodynamic monitoring. EIT has recently been shown to allow the assessment of aortic blood pressure via the estimation of the aortic pulse arrival time (PAT).
View Article and Find Full Text PDFElectrical impedance tomography (EIT) is a non-invasive imaging technique that can measure cardiac-related intra-thoracic impedance changes. EIT-based cardiac output estimation relies on the assumption that the amplitude of the impedance change in the ventricular region is representative of stroke volume (SV). However, other factors such as heart motion can significantly affect this ventricular impedance change.
View Article and Find Full Text PDFCooperative sensors is a novel measurement architecture that allows the acquiring of biopotential signals on patients in a comfortable and easy-to-integrate manner. The novel sensors are defined as cooperative in the sense that at least two of them work in concert to measure a target physiological signal, such as a multi-lead electrocardiogram or a thoracic bioimpedance.This paper starts by analysing the state-of-the-art methods to simultaneously measure biopotential and bioimpedance signals, and justifies why currently (1) passive electrodes require the use of shielded or double-shielded cables, and (2) active electrodes require the use of multi-wired cabled technologies, when aiming at high quality physiological measurements.
View Article and Find Full Text PDFAims: Recent studies suggest a relevant association of post-interventional residual platelet aggregation (RPA) under therapy with oral platelet inhibitors and the occurrence of atherothrombotic events. The influence of post-interventional RPA on the incidence of stent thrombosis (ST) has not been sufficiently evaluated in consecutive unselected cohorts of percutaneous coronary intervention (PCI) patients. The aim of this observational study was to investigate the impact of RPA on the incidence of ST within 3 months in patients treated with dual antiplatelet therapy.
View Article and Find Full Text PDFThe results of a simplified quantitative broth dilution quantitative tip culture (QTC) of 331 central venous catheters were compared with clinical data prospectively recorded in critically III patients to diagnose bacteremic or nonbacteremic catheter-related sepsis (CRS) (36 catheters), as opposed to contamination (42 catheters) or simple colonization from a distant septic focus (seven catheters). Thirty-five of 36 catheters associated with CRS yielded 10(3) colony-forming units per milliliter (CFU/mL) or more, and 3.8 X 10(2) Candida organisms grew from one.
View Article and Find Full Text PDFAm Rev Respir Dis
January 1987
The release of platelet-derived vasoactive substances, particularly serotonin (5-HT), have been implicated in the pulmonary vasoconstrictor response following acute pulmonary embolism. Therefore, we studied the effects of infusing ketanserin, a 5-HT blocking agent, upon pulmonary and systemic hemodynamics and gas exchange in 10 patients with severe acute pulmonary embolism. These patients evidenced 45 +/- 17% mean angiographic pulmonary vascular obstruction.
View Article and Find Full Text PDFAn explanation is provided of the logical steps taken before assigning patients to critical care therapy in a major multidisciplinary intensive care unit of the University of Paris at the Hospital Henri Mondor. The factors considered by the staff in deciding to terminate intensive therapy are also enumerated. This system has not been influenced by the major legal pressures found in the United States but has been shaped by more chronic fiscal constraints.
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