Hollow-Structured Ti3C2Tx Composite Fibers for Enhanced Pressure-Humidity Bifunctional Sensing in Febrile Convulsion Detection.

Complex Febrile Seizures Associated with Doose vs Dravet Syndrome Presentation of a Clinical Case

Wearable sensors for breathing rate (BR) monitoring are gaining increasing interest in sports applications. Particularly, resistive strain sensors are being extensively studied, thanks to their ability to monitor BR by recording the movements of the chest wall during breathing cycles. In this work, wearable screen-printed BR resistive strain sensors were realized and characterized using two different commercial textiles, and for each of them a geometry with two different dimensions. To assess the characteristics of the four resulting textile-sensor combinations, cyclic electromechanical tests were performed. The results allowed to select the most suitable textile and sensor dimension for the specific application, which is characterized by a sensitivity of 22 ± 2%, good stability over time and negligible drift. The optimized device was then tested on a human subject, which demonstrated the possibility to realize a simple low cost wearable sensor for BR monitoring.

BackgroundLongitudinal monitoring of vital signs provides a method for identifying changes to general health in an individual, particularly in older adults. The nocturnal sleep period provides a convenient opportunity to assess vital signs. Contactless technologies that can be embedded into the bedroom environment are unintrusive and burdenless and have the potential to enable seamless monitoring of vital signs. To realize this potential, these technologies need to be evaluated against gold standard measures and in relevant populations.ObjectiveWe aimed to evaluate the accuracy of heart rate and breathing rate measurements of 3 contactless technologies (2 undermattress trackers, Withings Sleep Analyzer [WSA] and Emfit QS [Emfit]; and a bedside radar, Somnofy) in a sleep laboratory environment and assess their potential to capture vital signs in a real-world setting.MethodsData were collected from 35 community-dwelling older adults aged between 65 and 83 (mean 70.8, SD 4.9) years (men: n=21, 60%) during a 1-night clinical polysomnography (PSG) test in a sleep laboratory, preceded by 7 to 14 days of data collection at home. Several of the participants (20/35, 57%) had health conditions, including type 2 diabetes, hypertension, obesity, and arthritis, and 49% (17) had moderate to severe sleep apnea, while 29% (n=10) had periodic leg movement disorder. The undermattress trackers provided estimates of both heart rate and breathing rate, while the bedside radar provided only the breathing rate. The accuracy of the heart rate and breathing rate estimated by the devices was compared with PSG electrocardiogram-derived heart rate (beats per minute) and respiratory inductance plethysmography thorax-derived breathing rate (cycles per minute), respectively. We also evaluated breathing disturbance indexes of snoring and the apnea-hypopnea index, available from the WSA.ResultsAll 3 contactless technologies provided acceptable accuracy in estimating heart rate (mean absolute error <2.12 beats per minute and mean absolute percentage error <5%) and breathing rate (mean absolute error ≤1.6 cycles per minute and mean absolute percentage error <12%) at 1-minute resolution. All 3 contactless technologies were able to capture changes in heart rate and breathing rate across the sleep period. The WSA snoring and breathing disturbance estimates were also accurate compared with PSG estimates (WSA snore: r2=0.76; P<.001; WSA apnea-hypopnea index: r2=0.59; P<.001).ConclusionsContactless technologies offer an unintrusive alternative to conventional wearable technologies for reliable monitoring of heart rate, breathing rate, and sleep apnea in community-dwelling older adults at scale. They enable the assessment of night-to-night variation in these vital signs, which may allow the identification of acute changes in health, and longitudinal monitoring, which may provide insight into health trajectories.International Registered Report Identifier (IRRID)RR2-10.3390/clockssleep6010010

Good quality sleep is essential for good health and sleep monitoring becomes a vital research topic. This paper provides a low cost, continuous and contactless WiFi-based vital signs (breathing and heart rate) monitoring method. In particular, we set up the antennas based on Fresnel diffraction model and signal propagation theory, which enhances the detection of weak breathing/heartbeat motion. We implement a prototype system using the off-shelf devices and a real-time processing system to monitor vital signs in real time. The experimental results indicate the accurate breathing rate and heart rate detection performance. To the best of our knowledge, this is the first work to use a pair of WiFi devices and omnidirectional antennas to achieve real-time individual breathing rate and heart rate monitoring in different sleeping postures.

Sleep monitoring has drawn increasing attention as sleep quality is important to maintain a person’s well-being. For instance, serious health problems, such as cardiovascular disease, fatigue, or depression, are usually associated with inadequate and irregular sleep. Traditional sleep monitoring systems involve wearable sensors with professional installation, and thus are usually limited to clinical usage. Recent work for sleep monitoring can detect several sleep events, such as coughing and snoring, using smartphone sensors. However, such coarse-grained sleep monitoring is unable to detect the breathing rate which is an important health indicator. In this paper, we present a fine-grained sleep monitoring system to detect the breathing rate and sleep events simultaneously by leveraging smartphones. Our system exploits the readily available smartphone earphone placed close to the user to reliably capture the human breathing sound. Given the captured acoustic sound, noise reduction is performed to remove the environmental noise and the breathing rate is then identified based on the signal envelope detection. Our system can further detect some sleep events, including snoring, coughing, turning over, and getting up, based on the features extracted from the acoustic sound. Moreover, we develop a body movement-assisted sleep event detection method to provide higher detection accuracy by further exploiting the user’s body movement patterns captured by the accelerometer embedded on smartphones. Our extensive experiments involving nine subjects over six months confirm the effectiveness of our proposed system on breathing rate monitoring and sleep events detection under various environments. By combining breathing rate and sleep events, our system can provide noninvasive and continuous fine-grained sleep monitoring for healthcare related applications, such as sleep apnea monitoring, as evidenced by our experimental study.

Sleep monitoring has drawn increasingly attention as the quality and quantity of the sleep are important to maintain a person's health and well-being. For example, inadequate and irregular sleep are usually associated with serious health problems such as fatigue, depression and cardiovascular disease. Traditional sleep monitoring systems, such as PSG, involve wearable sensors with professional installations, and thus are limited to clinical usage. Recent work in using smartphone sensors for sleep monitoring can detect several events related to sleep, such as body movement, cough and snore. Such coarse-grained sleep monitoring however is unable to detect the breathing rate which is an important vital sign and health indicator. This work presents a fine-grained sleep monitoring system which is capable of detecting the breathing rate by leveraging smartphones. Our system exploits the readily available smartphone earphone placed close to the user to reliably capture the human breathing sound. Given the captured acoustic sound, our system performs noise reduction to remove environmental noise and then identifies the breathing rate based on the signal envelope detection. Our system can further detect detailed sleep events including snore, cough, turn over and get up based on the acoustic features extracted from the acoustic sound. Our experimental evaluation of six subjects over six months time period demonstrates that the breathing rate monitoring and sleep events detection are highly accurate and robust under various environments. By combining breathing rate and sleep events, our system can provide continuous and noninvasive fine-grained sleep monitoring for healthcare related applications, such as sleep apnea monitoring as evidenced by our experimental study.

Clinical scenarios could be characterized by several adverse conditions. For this reason, it is important to ensure a safety interaction between medical equipment and patients. In this context, optical fiber-based technologies are becoming very popular because they are considered intrinsically safe and immune to electromagnetic interferences. Among them, Fiber Bragg Grating (FBG) sensors are gaining in importance for the monitoring of physiological parameters like breathing rate (BR), heart rate, and body temperature. Moreover, among many procedures, polymer functionalization of the fiber optic allows making FBG sensitive to chemical parameters, including: relative humidity (RH), pH, gas, and biomolecules. In this study, we investigated the possibility of using a FBG-based needle for monitoring both RH and BR during mechanical ventilation. Regarding RH estimation, we performed a qualitative analysis to assess if the probe is able to follow RH changes, during mechanical ventilation. The proposed systems experienced a Bragg wavelength shift of ~0.38 nm for RH changes from ~20% to ~90% and vice versa. The performance of the needle for BR estimation was investigated at different minute volumes (MV) and BR set by using the ventilator, covering the values used in the adult ventilation. The BR values estimated by the system were compared to the ones provided by the mechanical ventilator, and used as reference. The absolute value of the percentage errors $(\varepsilon _{\mathrm {e}\mathrm {r}\mathrm {r}}\%)$ was always lower than 3.7% (in the 90% of cases it was <1.8%).

Vital sign monitoring is fundamental in daily patient care. Wearable technology has become an important tool in personalized medicine; however, there is a tradeoff problem between accuracy and comfort caused by the elastic textile used. Our study sought to examine the accuracy of heart rate (HR) and breathing rate (BR) monitoring as measured by iSmartweaR, a novel wearable and wireless sensor that uses the laser Doppler technique, with special focus on sex and different static postures. A total of 30 male and 23 female patients, including 23 patients with cardiovascular diseases and 30 healthy participants, were recruited. The HR and BR were measured with iSmartweaR and the gold standard method (CardioSoft and MasterScreen™ CPX) simultaneously in three static postures (supine rest, right lateral decubitus, and left lateral decubitus). The mean errors of HR and BR between iSmartweaR and the gold standard method were close to zero (0.55 and 0.71, respectively). The standard deviations of the HR error and BR error were 0.59 and 0.67, respectively. Disease, posture, sex, and measurement time did not cause clinically significant measurement errors. The overall percentage of missing data was 7.01%. The use of iSmartweaR was valid across different sexes and static postures. It is real-time, continuous and manpower-saving, and can be applied in patient care.

With a burst development of new nanomaterials for plasmon-free surface-enhanced Raman scattering (SERS), the understanding of chemical mechanism (CM) and further applications have become more and more attractive. Herein, a novel SERS platform was specially designed through electrochemical deposition of graphene onto TiO2 nanoarrays (EG-TiO2). The developed EG-TiO2 nanocomposite SERS platform possessed remarkable Raman activity using copper phthalocyanine (CuPc) as a probe molecule. X-ray photoelectron spectroscopy measurement revealed that the chemical bond Ti-O-C was formed at the interface between graphene and TiO2 in EG-TiO2 nanocomposites. Both experimental and theoretical results demonstrated that the obvious Raman enhancement was attributed to TiO2-induced Fermi level shift of graphene, resulting in effective charge transfer between EG-TiO2 nanocomposites and molecules. Taking advantage of a marked Raman response of the CuPc molecule on the EG-TiO2 nanocomposite surface as well as specific recognition of CuPc toward multiple telomeric G-quadruplex, EG-TiO2 nanocomposites were tactfully employed as the SERS substrate for selective and ultrasensitive determination of telomerase activity, with a low detection limit down to 2.07 × 10-16 IU. Interestingly, the self-cleaning characteristic of EG-TiO2 nanocomposites under visible light irradiation successfully provided a recycling ability for this plasmon-free EG-TiO2 substrate. The present SERS biosensor with high analytical performance, such as high selectivity and sensitivity, has been further explored to determine telomerase activity in stem cells as well as to count the cell numbers. More importantly, using this useful tool, it was discovered that telomerase activity plays an important role in the proliferation and differentiation from human mesenchymal stem cells to neural stem cells. This work has not only established an approach for gaining fundamental insights into the chemical mechanism (CM) of Raman enhancement but also has opened a new way in the investigation of long-term dynamics of stem cell differentiation and clinical drug screening.

Background: Wearable sensor technologies coupled with secure patient portals allow for continuous real-time data acquisition from a patient in a hospital or home setting. This combination renders more effective health-management system with faster patient-recovery times and reduced healthcare costs. VitalConnect Inc. has developed a fully-disposable, FDA-cleared (for adults) wireless biosensor (VitalPatch®) that is worn on chest. VitalPatch captures multiple medical-grade biometrics and transmits the physiological data continuously (via Bluetooth) for up to 96 hours to a relay (tablet, wireless hub). Like adults, pediatric patients (5-17 years of age) could also benefit from such small and low-profile biosensor that can collect and stream vital signs uninterruptedly to a secure patient-portal. This data can then be monitored by a clinical triage center or healthcare-provider. Objective: Continuous remote monitoring of heart rate (HR) and breathing rate (BR) is critical during acute or chronic illnesses. The primary purpose of this study was to evaluate the performance of the VitalConnect platform in pediatric subjects during activities of daily living (ADL) to confirm accuracy of sensor measurements for HR and BR with respect to a clinical reference device, Capnostream20 (Oridion). Additionally, information on comfort and usability of VitalPatch at home was assessed for the total duration of wear. Methods: Thirty-five children were enrolled in the study (24 between 9-17 years, 11 between 5-8 years). All subjects participated in 96-hour wear-period of the VitalPatch biosensor and performed one hour of in-lab protocol on Day1 of the wear duration. Each participant underwent stationary breathing exercises (spontaneous, metronome), ADLs with postural maneuvers and treadmill walking. The study was conducted in presence of a nurse after approval from Institutional Review Board. The performance of heart rate, respiration rate, posture and number of steps were assessed for each subject separately using the mean absolute error (MAE) between the true and measured values. The reference for posture and step count was manual observation. Results: During the stationary condition, MAE (across 35 children) for HR and BR was 2.1±1.0 beats per minute (BPM) and 2.2±0.8 breaths per minute (BrPM) respectively compared to Capnostream20. During ADLs, MAE was 4.3±2.7 BPM for HR and 3.7±1.7 BrPM for BR. Accuracy of posture (standing, supine, walking) was >93% and step-count was >95% overall. Moreover, 80% participants rated wearing VitalPatch ‘comfortable’ without any itchiness during 96-hour wear. Conclusions: The VitalPatch biosensor demonstrated clinically-acceptable accuracy compared to a standardized reference device for both heart rate and breathing rate. It also provided sufficiently accurate measures for activity in terms of posture and number of steps. Furthermore, when used for up to 4 days at home, there were no adverse events (i.e. rashes, dermatitis, mechanical skin injury) and user experience was satisfactory. The accuracy of vitals and ease-of-use in the home environment in children aged 5-17 illustrate the potential of VitalPatch as a non-invasive and cost-effective vital sign monitoring alternative. VitalPatch biosensor can be integrated into state-of-art devices to monitor vital signs for pediatric patients with diseases like congenital heart abnormalities and adolescent fatigue. [iproc 2017;3(1):e5]

Sleep monitoring has drawn increasingly attention as the quality and quantity of the sleep are important for maintaining a person's health and well-being. For example, inadequate and irregular sleep are usually associated with serious health problems such as fatigue, depression and cardiovascular disease. Traditional sleep monitoring systems, such as PSG, involve wearable sensors with professional installations, and thus are limited to clinical usage. Recent work in using smartphone sensors for sleep monitoring can detect several events related to sleep, such as body movement, cough and snore. Such coarse-grained sleep monitoring however is unable to detect the breathing rate which is a vital sign and health indicator. This work presents a fine-grained sleep monitoring system which is capable of detecting the breathing rate by leveraging smartphones. Our system exploits the readily available smartphone earphone that placed close to the user to capture the breath sound reliably. Given the captured acoustic signal, our system performs noise reduction to remove environmental noise and then identifies the breathing rate based on the signal envelope detection. Our experimental evaluation of six subjects over six months time period demonstrates that the breathing rate monitoring is highly accurate and robust under various environments. This strongly indicates the feasibility of using the smartphone and its earphone to perform continuous and noninvasive fine-grained sleep monitoring.

Textile-based sensors are being integrated into garments for the monitoring of physiological signals from the human body. Commonly, textile sensors are implemented through knitting methods, while the response of these sensors from other structures has been less studied. This work analyzed the feasibility of using a textile-based stretch sensor with a coverstitch formation integrated into a commercial shirt for monitoring breathing patterns. For comparison, a Respiratory Inductive Plethysmograph (RIP) based breathing system was used. Data from three subjects performing eight different activities were collected in a controlled environment. The performance of the textile sensor was evaluated based on the mean absolute error breathing rate captured using different segment sizes and as the degree of correlation to the RIP sensor. Results showed an average breathing rate error of 0.97+0.42 breaths/epoch for an epoch size of 10s. The average correlation with the RIP sensor signals was p=0.41+0.2. Results suggest that this garment-integrated sensor could be potentially used in the monitoring of breathing rate.

Assessments of respiratory response and animal activity are useful endpoints in drug pharmacology and safety research. We investigated whether continuous, direct monitoring of breathing rate and body motion in animals in the home cage using the Vum Digital Smart House can complement standard measurements in enabling more granular detection of the onset and severity of physiologic events related to lung injury in a well-established rodent model of paraquat (PQ) toxicity. In rats administered PQ, breathing rate was significantly elevated while body motion was significantly reduced following dosing and extending throughout the 14-day study duration for breathing rate and at least 5 days for both nighttime and daytime body motion. Time course differences in these endpoints in response to the potential ameliorative test article bardoxolone were also readily detected. More complete than standard in-life measurements, breathing rate and body motion tracked injury progression continuously over the full study time period and aligned with, and informed on interval changes in clinical pathology. In addition, breathing rates correlated with terminal pathology measurements, such as normalized lung weights and histologic alveolar damage and edema. This study is a preliminary evaluation of the technology; our results demonstrate that continuously measured breathing rate and body motion served as physiologically relevant readouts to assess lung injury progression and drug response in a respiratory injury animal model.

Non-contact breathing rate monitoring in newborns: A review

Low hysteresis and high sensitivity TPU/carbonized wood cellulose sponge sensors for monitoring dynamic pulses.