Device For Long-term Monitoring Research Articles

Effect of Volatile Organic Compounds Adsorption on 3D-Printed PEGDA:PEDOT for Long-Term Monitoring Devices.

We report on the preparation and stereolithographic 3D printing of a resin based on the composite between a poly(ethylene glycol) diacrylate (PEGDA) host matrix and a poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) filler, and the related cumulative volatile organic compounds’ (VOCs) adsorbent properties. The control of all the steps for resin preparation and printing through morphological (SEM), structural (Raman spectroscopy) and functional (I/V measurements) characterizations allowed us to obtain conductive 3D objects of complex and reproducible geometry. These systems can interact with chemical vapors in the long term by providing a consistent and detectable variation of their structural and conductive characteristics. The materials and the manufacture protocol here reported thus propose an innovative and versatile technology for VOCs monitoring systems based on cumulative adsorption effects.

Measuring complex for monitoring carbon dioxide in air

The advantages and disadvantages of infrared and electrochemical gas analyzers for carbon dioxide CO2 are described. The possibility of using conductometric sensors with distilled water for monitoring the CO2 content in the air has been investigated. Two identical measuring systems were manufactured, each containing two open-type conductometric cells, a matching device and a personal computer. With the help of these complexes, experiments were carried out on the simultaneous measurement of the CO2 content in the air in two places (a laboratory room and a building in a forest, located at a distance of 15 km from each other) with deliberately different daily dynamics of the CO2 level change. A special experiment was carried out, which made it possible to obtain an estimate of the inertia of conductometric cells and a conversion factor for the values of CO2 content into standard units of measurement. It is shown that the daily dynamics of changes in the electrical conductivity of distilled water in open cells corresponds to the expected dynamics of changes in the CO2 content in the rooms where the measurements were carried out. The operability of the measuring complex and the possibility of creating on its basis a device for long-term monitoring of the CO2 content in the air mixture of gases has been confirmed. The principal high selectivity of the measuring complex to CO2 in relation to other gases of the atmosphere has been established.

Clinical utility of a personalized and long-term monitoring device for Parkinson's disease in a real clinical practice setting: An expert opinion survey on STAT-ON™

BackgroundSTAT-ON™ is an objective tool that registers ON-OFF fluctuations making possible to know the state of the patient at every moment of the day in normal life. Our aim was to analyze the opinion of different Parkinson's disease experts about the STAT-ON™ tool after using the device in a real clinical practice setting (RCPS). MethodsSTAT-ON™ was provided by the Company Sense4Care to Spanish neurologists for using it in a RCPS. Each neurologist had the device for at least three months and could use it in PD patients at his/her own discretion. In February 2020, a survey with 30 questions was sent to all participants. ResultsTwo thirds of neurologists (53.8% females; mean age 44.9±9 years old) worked in a Movement Disorders Unit, the average experience in PD was 16±6.9 years, and 40.7% of them had previously used other devices. A total of 119 evaluations were performed in 114 patients (range 2–9 by neurologist; mean 4.5±2.3). STAT-ON™ was considered “quite” to “very useful” by 74% of the neurologists with an overall opinion of 6.9±1.7 (0, worst; 10, best). STAT-ON™ was considered better than diaries by 70.3% of neurologists and a useful tool for the identification of patients with advanced PD by 81.5%. Proper identification of freezing of gait episodes and falls were frequent limitations reported. ConclusionSTAT-ON™ could be a useful device for using in PD patients in clinical practice.

First clinical experience with the wearable cardiac rhythm long-term monitoring cardioskin device

Abstract Background There are only limited options for long-term cardiac monitoring devices readily available in clinical practice for outpatients. Holter monitoring devices are limited by the uncomfort of wires and patches, the small number of leads for analysis, the quality of recordings or the monitoring duration while insertable cardiac monitors are costly and exposed to potential local complication. Purpose To describe a single center experience with a novel wearable device for cardiac rhythm monitoring. Methods The Cardioskin™ system is a patch-free, wire-free, wearable device with rechargeable batteries that provides a high quality 15-lead electrocardiogram monitoring over 1 month (Figure 1). Data are sent using a mobile application downloaded in the patient smartphone to a central Corelab where they can be interpreted by an expert and/or the prescribing physician. An alarm signal is readily available within the Cardioskin™ device, to allow patients to indicate the presence of symptoms. In this single center retrospective registry, we provide a first report of the use of this novel device in real world practice, with indication and duration of cardiac monitoring left at the physicans “discretion”. Results From January 2019 to December 2019, the Cardioskin™ system was prescribed in 60 patients for an overall median duration of 26.5 (14–32) days. The mean age of the patients was 45±12.2 years and 24 (40%) were male. Indications for cardiac monitoring were post-Stroke, palpitation, syncope and cardiomyopathy assessment in 56%, 30%, 7% and 7% of the cases, respectively. A sustained (>30 seconds) supraventricular tachycardia was detected in 4 cases, including one case of atrial fibrillation, two case of atrial tachycardia and on case of junctional tachycardia. Unsustained ventricular tachycardia and atrial fibrillation burst were detected in another 2 cases (Figure 1). There was no reported case of skin irritation by the Cardioskin™ system or abrupt interruption of the monitoring by the patients. Conclusion The Cardioskin™ system is a novel, discreet and comfortable cardiac rhythm wearable long-term monitoring device which can be used in clinical practice for broad diagnostic indications. Figure 1. Cardioskin system Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): ACTION coeur

Perbandingan Real-Valued dan Complex Wavelet Transform pada Denoising Sinyal Fetal-Phonocardiograms (Comparison of Fetal-Phonocardiogram Signal Denoising based on Real- Valued and Complex Wavelet Transform)

Monitoring of Fetal Heart Rate (FHR) in the pregnancy period commonly uses the Doppler-based instruments despite having several disadvantages, such as high-cost and complexity of the monitoring system. Implementation of the passive and non-invasive method based on fetal phonocardiogram (fPCG), the acoustic recording of fetus cardiac signal, can be used as a potentially economical long-term monitoring device for diagnosis. Because the interference signal from the maternal women exists, the matured denoising technique was needed to implement the fPCG method to diagnose the fetus' well-being condition. The denoising system based on Dual-tree Complex Wavelet Transforms (DTCWT) was proposed in this paper. The proposed method was evaluated using Signal to Noise Ratio (SNR). Based on the experiment result from 37 fPCG signals from physio.net, the DTCWT system performance was compared with the Discrete Wavelet Transform (DWT). There were 24 CWT’s denoised fPCG signals that have successfully outperformed DWT’s SNR. DTCWT has also reduced the noises in the range of 30 Hz–80 Hz. Also, it emphasized the existence of dominant frequencies in the range of 60 Hz–65 Hz.

Ingestible hydrogel device

Devices that interact with living organisms are typically made of metals, silicon, ceramics, and plastics. Implantation of such devices for long-term monitoring or treatment generally requires invasive procedures. Hydrogels offer new opportunities for human-machine interactions due to their superior mechanical compliance and biocompatibility. Additionally, oral administration, coupled with gastric residency, serves as a non-invasive alternative to implantation. Achieving gastric residency with hydrogels requires the hydrogels to swell very rapidly and to withstand gastric mechanical forces over time. However, high swelling ratio, high swelling speed, and long-term robustness do not coexist in existing hydrogels. Here, we introduce a hydrogel device that can be ingested as a standard-sized pill, swell rapidly into a large soft sphere, and maintain robustness under repeated mechanical loads in the stomach for up to one month. Large animal tests support the exceptional performance of the ingestible hydrogel device for long-term gastric retention and physiological monitoring.

Automated real-time method for ventricular heartbeat classification

Background and objective: In this work, we develop a fully automatic and real-time ventricular heartbeat classifier based on a single ECG lead. Single ECG lead classifiers can be especially useful for wearable technologies that provide continuous and long-term monitoring of the electrocardiogram. These wearables usually have a few non-standard leads and the quality of the signals depends on the user physical activity.Methods: The proposed method uses an Echo State Network (ESN) to classify ECG signals following the Association for the Advancement of Medical Instrumentation (AAMI) recommendations with an inter-patient scheme. To achieve real-time classification, the classifier itself and the feature extraction approach are fast and computationally efficient. In addition, our approach allows transferring the knowledge from one database to another without additional training.Results: The classification performance of the proposed model is validated on the MIT-BIH arrhythmia and INCART databases. The sensitivity and precision of the proposed method for MIT-BIH arrhythmia database are 95.3 and 88.8 for the modified lead II and 90.9 and 89.2 for the V1 lead. The results reported are further compared to the existing methodologies in literature. Our methodology is a competitive single lead ventricular heartbeat classifier, that is comparable to state-of-the-art algorithms using multiple leads.Conclusions: The proposed fully automated, single-lead and real-time heartbeat classifier of ventricular heartbeats reports an improved classification accuracy in different leads of the evaluated databases in comparison with other single lead heartbeat classifiers. These results open the possibility of applying our methodology to wearable long-term monitoring devices with an unconventional placement of the electrodes.

Updates on Prevention of Cardioembolic Strokes.

Cardiac embolism continues to be a leading etiology of ischemic strokes worldwide. Although pathologies that result in cardioembolism have not changed over the past decade, there have been significant advances in the treatment and stroke prevention methods for these conditions. Atrial fibrillation remains the prototypical cause of cardioembolic strokes. The availability of new long-term monitoring devices for atrial fibrillation detection such as insertable cardiac monitors has allowed accurate detection of this leading cause of cardioembolism. The non-vitamin K antagonist oral anticoagulants have improved our ability to prevent strokes for many patients with non-valvular atrial fibrillation (NVAF). Advances in left atrial appendage closure and the U.S. Food and Drug Administration approval of the WATCHMAN (Boston Scientific) device for stroke prevention in NVAF patients who have an appropriate rationale for a nonpharmacological alternative, have revolutionized the field and provided a viable option for patients at higher hemorrhagic risk. The role of patent foramen ovale closure for secondary prevention in selected patients experiencing cryptogenic ischemic strokes at a relatively young age has become clearer thanks to the very recent publication of long-term outcomes from three major studies. Advances in the management of infective endocarditis, heart failure, valvular diseases, and coronary artery disease have significantly changed the management of such patients, but have also revealed new concerns related to assessment of ischemic versus hemorrhagic risk in the setting of antithrombotic use. The current review article aims to discuss these advances especially as they pertain to the stroke neurology practice.

Protocol with self‐adaptive GB for BANs

Body area networks (BANs) are systems of wearable computing devices for long-term monitoring of personal health care. BAN is an emerging technology for the worldwide ageing population. In the BAN system, the transceiver is the most energy-consuming part of a sensor node and radio transmission in the vicinity of the human body is highly lossy and inefficient. Therefore, the energy of the sensor node constraints the life cycle and quality of service of the network; consequently, low-cost protocol shaves attracted wide interest. This study proposes a frame structure model of a self-adaptive guard band protocol, which introduces a GB in each time slot according to the allowed maximum time drift of the crystal, adaptively adjusts the value of the GB based on the actual time drift, and then ensures that the node simultaneously maintains the sleeping state and synchronisation with the coordinator during beacon transmission, thus reducing the energy consumption.

Application of semipermeable membrane devices for long-term monitoring of polycyclic aromatic hydrocarbons at various stages of drinking water treatment

The primary goal of the presented study was the investigation of occurrence and concentration of sixteen selected polycyclic aromatic hydrocarbons in samples from various stages of water treatment and verification of the applicability of semi-permeable membrane devices in the monitoring of drinking water. Another objective was to verify if weather seasons affect the concentration and complexity of PAHs. For these purposes, semipermeable membrane devices were installed in a surface water treatment plant located in Lower Silesia (Poland). Samples were collected monthly over a period of one year. To determine the effect of water treatment on PAH concentrations, four sampling sites were selected: raw water input, a stream of water in the pipe just before ozonation, treated water output and water after passing through the distribution system. After each month of sampling, SPMDs were exchanged for fresh ones and prepared for instrumental analysis. Concentrations of polycyclic aromatic hydrocarbons were determined by high-performance liquid chromatography (HPLC). The presented study indicates that semipermeable membrane devices can be an effective tool for the analysis of drinking water, in which organic micropollutants occur at very low concentrations.

Fundamental evaluation of fixed position on water sensing device for long-term monitoring

Fundamental evaluation of fixed position on water sensing device for long-term monitoring

Performance comparison between wrist and chest actigraphy in combination with heart rate variability for sleep classification

The concurrent usage of actigraphy and heart rate variability (HRV) for sleep efficiency quantification is still matter of investigation. This study compared chest (CACT) and wrist (WACT) actigraphy (actigraphs positioned on chest and wrist, respectively) in combination with HRV for automatic sleep vs wake classification. Accelerometer and ECG signals were collected during polysomnographic studies (PSGs) including 18 individuals (25–53 years old) with no previous history of sleep disorders. Then, an experienced neurologist performed sleep staging on PSG data. Eleven features from HRV and accelerometry were extracted from series of different lengths. A support vector machine (SVM) was used to automatically distinguish sleep and wake. We found 7 min as the optimal signal length for classification, while maximizing specificity (wake detection). CACT and WACT provided similar accuracies (78% chest vs 77% wrist), larger than what yielded by HRV alone (66%). The addition of HRV to CACT reduced slightly the accuracy, while improving specificity (from 33% to 51%, p < 0.05). On the contrary, the concurrent usage of HRV and WACT did not provide statistically significant improvements over WACT. Then, a subset of features (3 from HRV + 1 from actigraphy) was selected by reducing redundancy using a strategy based on Spearman's correlation and area under the ROC curve. The usage of the reduced set of features and SVM classifier gave only slightly reduced classification performances, which did not differ from the full sets of features. The study opens interesting possibilities in the design of wearable devices for long-term monitoring of sleep at home.

Dynamic control and quantification of bacterial population dynamics in droplets

Culturing and measuring bacterial population dynamics are critical to develop insights into gene regulation or bacterial physiology. Traditional methods, based on bulk culture to obtain such quantification, have the limitations of higher cost/volume of reagents, non-amendable to small size of population and more laborious manipulation. To this end, droplet-based microfluidics represents a promising alternative that is cost-effective and high-throughput. However, difficulties in manipulating the droplet environment and monitoring encapsulated bacterial population for long-term experiments limit its utilization. To overcome these limitations, we used an electrode-free injection technology to modulate the chemical environment in droplets. This ability is critical for precise control of bacterial dynamics in droplets. Moreover, we developed a trapping device for long-term monitoring of population dynamics in individual droplets for at least 240 h. We demonstrated the utility of this new microfluidic system by quantifying population dynamics of natural and engineered bacteria. Our approach can further improve the analysis for systems and synthetic biology in terms of manipulability and high temporal resolution.

Voice accumulation and voice disorders in primary school teachers

Statistics on professional voice users with vocal health issues demonstrate the significance of the problem. However, such disorders are not currently recognized as an occupational disease in Italy. Conducting studies examining the vocal health of occupational voice users is an important step in identifying this as an important public health issue. The current study was conducted in six primary schools in Italy with 25 teachers, one of the most affected occupational categories. A clinical examination was conducted (consisting of hearing and voice screening, a VHI, etc.). On this basis, teachers were divided into three groups: healthy subjects, subject with logopaedic disorders, and subjects with objectively measured pathological symptoms. The distributions of voicing and silence periods for the teachers at work were collected using the Ambulatory Phonation Monitor (APM3200), a device for long-term monitoring of vocal parameters. The APM senses the vocal fold vibrations at the base of the neck by means of a small accelerometer. Correlations were calculated between the voice accumulation slope (obtained by multiplying the number of occurrences for each period by the corresponding duration) and the clinical status of the teachers. The differences in voice accumulation distributions among the three groups were analyzed.

Inertial sensing algorithms for long-term foot angle monitoring for assessment of idiopathic toe-walking

When children walk on their toes for no known reason, the condition is called Idiopathic Toe Walking (ITW). Assessing the true severity of ITW can be difficult because children can alter their gait while under observation in clinic. The ability to monitor the foot angle during daily life outside of clinic may improve the assessment of ITW. A foot-worn, battery-powered inertial sensing device has been designed to monitor patients’ foot angle during daily activities. The monitor includes a 3-axis accelerometer, 2-axis gyroscope, and a low-power microcontroller. The device is necessarily small, with limited battery capacity and processing power. Therefore a high-accuracy but low-complexity inertial sensing algorithm is needed. This paper compares several low-complexity algorithms’ aptitude for foot-angle measurement: accelerometer-only measurement, finite impulse response (FIR) and infinite impulse response (IIR) complementary filtering, and a new dynamic predict-correct style algorithm developed using fuzzy c-means clustering. A total of 11 subjects each walked 20m with the inertial sensing device fixed to one foot; 10m with normal gait and 10m simulating toe walking. A cross-validation scheme was used to obtain a low-bias estimate of each algorithm's angle measurement accuracy. The new predict-correct algorithm achieved the lowest angle measurement error: <5° mean error during normal and toe walking. The IIR complementary filtering algorithm achieved almost-as good accuracy with less computational complexity. These two algorithms seem to have good aptitude for the foot-angle measurement problem, and would be good candidates for use in a long-term monitoring device for toe-walking assessment.

A Novel Device for Long-Term Monitoring Freezing-of-Gait in People with Parkinson Disease: Case Study

A Novel Device for Long-Term Monitoring Freezing-of-Gait in People with Parkinson Disease: Case Study

Mobile wearable device for long term monitoring of vital signs

In long-term prevention and in rehabilitation of health of elderly people the recording of vital signs plays an important role. Especially the progress of rehabilitation can be deduced from the recording of an electrocardigram (ECG), blood pressure and body temperature. In this paper we present a wireless coupled recording device for long-term monitoring of these vital sign signals. We record the ECG, the blood pressure and the skin temperature and include a 3D-acceleration sensor for the determination of the movements during recording. To deal with motion artifacts in all recorded properties we use data fusion to reject or correct distorted vital sign signals.

Evaluation of Unconstrained Monitoring Technology Used in the Smart Bed for u-Health Environment

Since ubiquitous technology is an emerging paradigm in healthcare, we wanted to evaluate its feasibility in the healthcare area. As a first step, we evaluated the feasibility of the smart bed. In this study, a series of experiments were conducted to evaluate the smart bed. Smart bed is a continuous ballistocardiogram monitoring device developed by Seoul National University. Eleven healthy subjects participated in the study. Each subject slept in the smart bed for two nights. To measure meaningful sleep periods, noisy sections were removed from the original signal. The subject's heart activity was obtained by automatic peak detection, using the AF2 peak detection algorithm. In this study, the feasibility of the smart bed was evaluated in terms of the meaningful sleep periods and the accuracy of automatic peak detection. On an average, 92.8% of sleep duration was meaningful. The accuracy of peak detection algorithm was also evaluated. The algorithm proved to have an accuracy of 95%; thus, we observe that 95% of the peak detection results were correct in comparison with the manual results. Based on the experimental results, we conclude that the smart bed can be a useful device for long-term monitoring in ubiquitous healthcare environments.

The Etiology of Syncope in Patients With Negative Tilt Table and Electrophysiological Testing

Patients with syncope of unknown etiology after negative noninvasive and electrophysiological testing may suffer from recurrent disability. Syncopal episodes are often too infrequent and unpredictable for detection by conventional ambulatory monitoring techniques. A long-term subcutaneous monitoring device was implanted in patients with negative ambulatory monitoring, tilt table and electrophysiological testing to establish cardiac rhythm during spontaneous syncope. Sixteen patients aged 57 +/- 19 years with a mean of 8.4 +/- 4.4 previous episodes of syncope underwent device implantation. Fifteen patients (94%) had recurrent syncope 4.4 +/- 4.2 months after implantation. The remaining patient has not had recurrent syncope and continues to be followed. A diagnosis was obtained in every patient who had recurrent episode. Syncope was secondary to sinus arrest in 5, atrioventricular block in 2, ventricular tachycardia in 1, supraventricular tachycardia in 1, and nonarrhythmic in 6. Successful therapy was implemented in all 15 patients, without recurrence of syncope during 13.0 +/- 8.4 months of follow-up. Unexplained syncope in patients with negative investigations has a broad spectrum of etiologies, the most common of which is bradycardia. An implantable long-term monitoring device is useful for establishing a diagnosis when symptoms are recurrent but too infrequent for conventional monitoring techniques.

Microcomputer-based portable long-term spasticity recording system.

A device for long-term monitoring of muscle activity (EMG) with surface electrodes and method of its application are described in this paper. This device is called a microcomputer two-channel EMG monitor. The device can be used for up to 24 h monitoring of EMG activity, followed by data transfer to a host computer for signal analysis. This device records amplified, rectified, and integrated EMG activity. Shorter recording time allows shorter sampling periods suitable for different other EMG analysis. Recording of spontaneous EMG in complete spinal cord injured subjects was the original reason for the design of the long-term monitor. These recordings were used for estimation of spasticity in complete spinal cord patients.