Wearable breath monitoring based on a flexible fiber-optic humidity sensor

In this study, we fabricated a highly flexible fiber-based capacitive humidity sensor using a scalable convergence fiber drawing approach. The sensor’s sensing layer is made of porous polyetherimide (PEI) with its porosity produced in situ during fiber drawing, whereas its electrodes are made of copper wires. The porosity induces capillary condensation starting at a low relative humidity (RH) level (here, 70%), resulting in a significant increase in the response of the sensor at RH levels ranging from 70% to 80%. The proposed humidity sensor shows a good sensitivity of 0.39 pF/% RH in the range of 70%–80% RH, a maximum hysteresis of 9.08% RH at 70% RH, a small temperature dependence, and a good stability over a 48 h period. This work demonstrates the first fiber-based humidity sensor fabricated using convergence fiber drawing.

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CSRR Integrated Microwave Humidity Sensor Based Go@Mxene for Breath Monitoring

2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems & Eurosensors XXXIII (TRANSDUCERS & EUROSENSORS XXXIII) ◽

10.1109/transducers.2019.8808544 ◽

2019 ◽

Cited By ~ 1

Author(s):

Hairong Kou ◽

Qiulin Tan ◽

Lei Zhang ◽

Jijun Xiong ◽

Wendong Zhang

Keyword(s):

Humidity Sensor ◽

Breath Monitoring

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0561 Differences in Nasopharyngoscopic Airway Form Between Awake and Sleep, Sitting and Recumbent Position and Techniques

SLEEP ◽

10.1093/sleep/zsaa056.558 ◽

2020 ◽

Vol 43 (Supplement_1) ◽

pp. A215-A215

Author(s):

Y Nishimura ◽

M Hamed

Keyword(s):

Airway Obstruction ◽

Fiber Optic ◽

Upper Airway ◽

Apnea Hypopnea Index ◽

Recumbent Position ◽

Drug Induced ◽

Airway Narrowing ◽

Flexible Fiber ◽

Obstructive Sleep ◽

Anterior Posterior

Abstract Introduction To examine and compare the information derived from flexible fiber-optic nasopharyngoscopy in awake mimic snoring (AMS), Müller’s Maneuver (MM) and drug-induced sleep endoscopy (DISE), to determine if AMS and MM can be used in substitution for DISE as a streamlined method. We investigated their relation with the level and pattern of obstruction detected on AMS, MM and DISE. Methods This is a retrospective study of 15 obstructive sleep apnea patients with apnea hypopnea index from 8.3 to 105.2, ages 20 to 80 were included. Each patient underwent polysomnography and thorough a physical examination, including flexible nasopharyngoscopy with AMS, MM and DISE. Airway obstruction on these endoscopic procedures were described according to airway level and pattern of obstruction. They were classified 5 different types; Uvula type: anterior-posterior vibration of the uvula, no airway obstruction; L-R velum type: lateral (the left and right directions) airway narrowing at velum level, no airway obstruction; A-P velum type: anterior-posterior total airway obstruction at velum level; Tonsillar type: total airway obstruction at pharyngeal level; Circumferential type: circumferential total airway obstruction at velum level. AMS and MM were performed with patients in sitting and in recumbent position. DISE was performed only in recumbent position. Results In review of the three procedures, the results were much different. Airway was obstructed in all cases(100%, 15 of 15)in DISE, but not all cases in AMS and MM. When tonsillar type was seen in AMS, it was also seen in MM and DISE(100%, 5 of 5). Conclusion Flexible fiber-optic nasopharyngoscopy appears to be useful for evaluating airway obstruction. It might be not suitable to use AMS and MM in substitution for DISE(except tonsillar type). Muscle tonic relaxation of the upper airway between AMS, MM and DISE might be different (DISE>MM>AMS, recumbent>sitting). Support

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