We would like to acknowledge Mr. Ryohei Suganuma and Ms. Sakie Tachibana who helped perform the research. This study was supported in part by the JSPS KAKENHI Grant Numbers 15K20664, 24500848, and 21500405. This study was also funded in part by the MEXT/JST Tenure Track Promotion Program. A part of this study was based on the Japanese Unexamined Patent Application Publication No. 2011-169881 and the Japanese Patent No. 5708911.

NOTE: The device, including the method of analysis, is covered by Japanese Unexamined Patent Application Publication No. 2011-169881 and the Japanese Patent No. 5708911. This study, including the protocol of the experiment with human subjects, was approved by the Medical Ethics Committee of Kanazawa University (#553-1).
1. Prerequisites for the Perspiration Monitoring Device
NOTE: Perform these steps only once before the first use.
<ol>
	<li>Install the universal serial bus (USB)-serial port conversion interface drivers in the computer27. If the drivers are already installed, skip this step.</li>
	<li>Connect the USB-serial port conversion interface to the computer via USB cable. Wait for the automatic driver installation if any.</li>
	<li>Set the parameters of the conversion interface and check the ID number of the serial port as follows.
	<ol>
		<li>Open the device manager, and select [View] &#8594; [Devices by Type].</li>
		<li>Locate the &#34;Ports (COM &#38; LPT)&#34; heading, and expand the section to find the heading containing &#34;CP210x USB to UART Bridge&#34; in the list.</li>
		<li>Memorize the ID number of the port (e.g., &#34;COM5&#34;) in the &#34;CP210x USB to UART Bridge&#34; heading.</li>
		<li>Double click the &#34;CP210x USB to UART Bridge,&#34; and open the &#34;Port Settings&#34; tab.</li>
		<li>Set the parameters as follows: &#34;Bits per second&#34; = 9600, &#34;Data bits&#34; = 8, &#34;Parity&#34; = &#34;None,&#34; &#34;Stop bits&#34; = 1, and &#34;Flow control&#34; = &#34;None.&#34;</li>
		<li>Click the &#34;OK&#34; button to close the window, and close the device manager.</li>
	</ol>
	</li>
</ol>
2. Setup of the Perspiration Monitoring Device
NOTE: Set the recording settings as follows before using the device. Repeat these steps for each device if multiple devices are to be used.
<ol>
	<li>Make sure the battery is not inserted in the perspiration monitoring device.</li>
	<li>Plug the white connector of the USB-serial port conversion interface to the receptacle at the top of the perspiration monitoring device.</li>
	<li>Execute the perspiration recording software, followed by setting the device parameters as follows.
	<ol>
		<li>Open the &#34;Settings&#34; tab.</li>
		<li>Set the &#34;COM&#34; number to the ID number of the serial port (see step 1.3.3).</li>
		<li>Click the &#34;Confirm Connection&#34; button. Check if the message &#34;Connected&#8230;&#34; appears.</li>
		<li>At the &#34;Data File Folder&#34; settings, choose the drive and select the folder where the perspiration data will be saved. To select the subfolder, double click the folder to open.</li>
		<li>Set the &#34;Number of holes&#34; to &#34;4.&#34;</li>
	</ol>
	</li>
	<li>Open the &#34;Measure &#38; Rec&#34; tab, and set the &#34;Time Interval&#34; to the desired sample time.</li>
	<li>Insert a battery to the perspiration monitoring device.</li>
	<li>Fill the device with dry silica gel (color should be blue or green if the color indicator is available), and close the lid. If the lid does not close completely, reduce the amount of silica gel.</li>
	<li>Click the &#34;Start Logging Now&#34; button in the perspiration recording software. 
	NOTE: Because the perspiration recording starts just after the disconnection, the perspiration monitoring device may be left connected until the monitoring is to be started.</li>
</ol>
3. Setup for the Measurement of Sympathetic Skin Response (SSR)
NOTE: These steps are intended to monitor the sympathetic activities as the palmar SSR, and are not necessarily required for perspiration monitoring itself. SSR is a change of skin potential according to the sympathetic arousal stimulation such as upset and concentration28,29.
<ol>
	<li>Cleanse the skin where the SSR is to be recorded with an alcohol swab.</li>
	<li>Put the anode, cathode, and grounding electrode on the palm, back of the hand, and wrist, respectively, by means of an electrode paste. Fix the electrodes with medical tape.</li>
	<li>Set the conditions of the instrumentation amplifier by turning the corresponding knobs of the amplifier as follows: Sensitivity = 1 mV/V, High cut filter (&#34;HI CUT&#34;) = 3 kHz, and Low cut filter (&#34;LO CUT&#34;) = 0.5 Hz.</li>
	<li>Execute the SSR recording software, and start the recording at a sampling rate of 200 Hz by clicking the &#34;Start Measurement&#34; button in the software.</li>
</ol>
4. Recording of the Perspiration
<ol>
	<li>Put a medical double-sided tape on the bottom of the perspiration monitoring device. When putting a tape, make sure the measurement windows (i.e.&#160;four holes at the bottom of the device) are not obstructed.</li>
	<li>Disconnect the perspiration monitoring device from the USB-serial port conversion interface. Immediately after the disconnection, observe the perspiration monitoring begin automatically. Make sure the LED lamp is blinking.</li>
	<li>Remove the release liner of the medical double-sided tape, and put the perspiration monitoring device on the skin where perspiration is to be monitored.</li>
	<li>Wait 10 min for stabilization of water vapor diffusion. 
	NOTE: Although this process cannot be monitored, the previous study has confirmed that waiting 10 min is sufficient for stable monitoring26.</li>
	<li>Start the examination (e.g., sympathetic activity test).</li>
	<li>After the examination, remove the perspiration monitoring device from the skin. To stop the SSR recording, click the &#34;Stop Measurement&#34; button in the SSR recording software, and remove all electrodes from the skin.</li>
</ol>
5. Perspiration Analysis
<ol>
	<li>Connect the perspiration monitoring device to the USB-serial port conversion interface (as in step 2.2).</li>
	<li>Execute the perspiration monitoring software.</li>
	<li>Open the &#34;Settings&#34; tab, and click the &#34;Confirm Connection&#34; button.</li>
	<li>Open the &#34;Measure &#38; Rec&#34; tab, and click the &#34;Download&#34; button to save the raw data of the device in the specified folder (see step 2.3.4).</li>
	<li>Perform perspiration analysis as follows.
	<ol>
		<li>Open the &#34;Analysis&#34; tab, and click the &#34;Read Data File.&#34; Observe the &#34;Open File&#34; dialog pop up. Select the saved file in the step 5.4, and then click the &#34;Open&#34; button. 
		NOTE: The software automatically performs perspiration analysis based on the published method26, and the results will appear on the screen. At the same time, the perspiration data as the comma-separated values format will be saved in the same folder.</li>
	</ol>
	</li>
</ol>

<ol>
	<li>Hardy, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Physiology+of+temperature+regulation.">Physiology of temperature regulation.</a> Physiol. Rev. 41, 521-606 (1961).</li><li>Niepomniszcze, H., Amad, R. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Skin+disorders+and+thyroid+diseases.">Skin disorders and thyroid diseases.</a> J. Endocrinol. Invest. 24 (8), 628-638 (2001).</li><li>Korpelainen, J. T., Sotaniemi, K. A., Myllyla, V. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hyperhidrosis+as+a+reflection+of+autonomic+failure+in+patients+with+acute+hemispheral+brain+infarction.+An+evaporimetric+study.">Hyperhidrosis as a reflection of autonomic failure in patients with acute hemispheral brain infarction. An evaporimetric study.</a> Stroke. 23 (9), 1271-1275 (1992).</li><li>Fealey, R. D., Low, P. A., Thomas, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermoregulatory+sweating+abnormalities+in+diabetes+mellitus.">Thermoregulatory sweating abnormalities in diabetes mellitus.</a> Mayo Clin Proc. 64 (6), 617-628 (1989).</li><li>Leung, A. K., Chan, P. Y., Choi, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hyperhidrosis.">Hyperhidrosis.</a> Int J Dermatol. 38 (8), 561-567 (1999).</li><li>Kronenberg, F., Cote, L. J., Linkie, D. M., Dyrenfurth, I., Downey, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Menopausal+hot+flashes:+thermoregulatory,+cardiovascular,+and+circulating+catecholamine+and+LH+changes.">Menopausal hot flashes: thermoregulatory, cardiovascular, and circulating catecholamine and LH changes.</a> Maturitas. 6 (1), 31-43 (1984).</li><li>Gibson, L. E., Cooke, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+test+for+concentration+of+electrolytes+in+sweat+in+cystic+fibrosis+of+the+pancreas+utilizing+pilocarpine+by+iontophoresis.">A test for concentration of electrolytes in sweat in cystic fibrosis of the pancreas utilizing pilocarpine by iontophoresis.</a> Pediatrics. 23 (3), 545-549 (1959).</li><li>Swinn, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sweating+dysfunction+in+Parkinson's+disease.">Sweating dysfunction in Parkinson's disease.</a> Mov. Disord. 18 (12), 1459-1463 (2003).</li><li>Davidson, J. R., Foa, E. B., Connor, K. M., Churchill, L. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hyperhidrosis+in+social+anxiety+disorder.">Hyperhidrosis in social anxiety disorder.</a> Prog. Neuropsychopharmacol. Biol. Psychiatry. 26 (7-8), 1327-1331 (2002).</li><li>Gun Park, D., Chul Shin, S., Won Kang, S., Tae Kim, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+flexible+self+adhesive+patch+for+professional+heat+stress+monitoring+service.">Development of flexible self adhesive patch for professional heat stress monitoring service.</a> Conf. Proc. IEEE Eng. Med. Biol. Soc. 4, 3789-3792 (2005).</li><li>Pickup, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preliminary+evaluation+of+a+skin+conductance+meter+for+detecting+hypoglycemia+in+diabetic+patients.">Preliminary evaluation of a skin conductance meter for detecting hypoglycemia in diabetic patients.</a> Diabetes Care. 5 (3), 326-329 (1982).</li><li>Stenstrom, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+study+on+skin+humidity+in+leprosy+patients+using+a+new+type+of+humidity+meter.">A study on skin humidity in leprosy patients using a new type of humidity meter.</a> Int. J. Lepr. Other Mycobact. Dis. 52 (1), 10-18 (1984).</li><li>Monty, C. N., Wujcik, E. K., Blasdel, N. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flexible+Electrode+for+Detecting+Changes.">Flexible Electrode for Detecting Changes.</a> in Temperature, Humidity, and Sodium Ion Concentration in Sweat. , (2013).</li><li>Wujcik, E. K., Blasdel, N. J., Trowbridge, D., Monty, C. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ion+Sensor+for+the+Quantification+of+Sodium+in+Sweat+Samples.">Ion Sensor for the Quantification of Sodium in Sweat Samples.</a> IEEE Sens. J. 13 (9), 3430-3436 (2013).</li><li>Blasdel, N. J., Wujcik, E. K., Carletta, J. E., Lee, K. S., Monty, C. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fabric+Nanocomposite+Resistance+Temperature+Detector.">Fabric Nanocomposite Resistance Temperature Detector.</a> IEEE Sens. J. 15 (1), 300-306 (2015).</li><li>Jia, W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrochemical+tattoo+biosensors+for+real-time+noninvasive+lactate+monitoring+in+human+perspiration.">Electrochemical tattoo biosensors for real-time noninvasive lactate monitoring in human perspiration.</a> Anal. Chem. 85 (14), 6553-6560 (2013).</li><li>Huang, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stretchable,+wireless+sensors+and+functional+substrates+for+epidermal+characterization+of+sweat.">Stretchable, wireless sensors and functional substrates for epidermal characterization of sweat.</a> Small. 10 (15), 3083-3090 (2014).</li><li>Rose, D. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adhesive+RFID+Sensor+Patch+for+Monitoring+of+Sweat+Electrolytes.">Adhesive RFID Sensor Patch for Monitoring of Sweat Electrolytes.</a> IEEE Trans. Biomed. Eng. 62 (6), 1457-1465 (2015).</li><li>Gao, W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fully+integrated+wearable+sensor+arrays+for+multiplexed+in+situ+perspiration+analysis.">Fully integrated wearable sensor arrays for multiplexed in situ perspiration analysis.</a> Nature. 529 (7587), 509-514 (2016).</li><li>Nilsson, G. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measurement+of+water+exchange+through+skin.">Measurement of water exchange through skin.</a> Med. Biol. Eng. Comput. 15 (3), 209-218 (1977).</li><li>Tagami, H., Kobayashi, H., Kikuchi, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+portable+device+using+a+closed+chamber+system+for+measuring+transepidermal+water+loss:+comparison+with+the+conventional+method.">A portable device using a closed chamber system for measuring transepidermal water loss: comparison with the conventional method.</a> Skin Res. Technol. 8 (1), 7-12 (2002).</li><li>Nuutinen, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+closed+unventilated+chamber+for+the+measurement+of+transepidermal+water+loss.">A closed unventilated chamber for the measurement of transepidermal water loss.</a> Skin Res. Technol. 9 (2), 85-89 (2003).</li><li>Imhof, R. E., De Jesus, M. E., Xiao, P., Ciortea, L. I., Berg, E. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Closed-chamber+transepidermal+water+loss+measurement:+microclimate,+calibration+and+performance.">Closed-chamber transepidermal water loss measurement: microclimate, calibration and performance.</a> Int. J. Cosmet. Sci. 31 (2), 97-118 (2009).</li><li>Sakaguchi, M., Ono, N., Ohhashi, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+skin+moisture+meter+using+absolute+hygrosensor.">A new skin moisture meter using absolute hygrosensor.</a> Tech. Rep. IEICE. 98 (309), 43-47 (1998).</li><li>Sakaguchi, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+the+new+ventilation+capsule+type+sweating-evaporation+ratemeter+-+measurements+of+local+sweating+rates+and+evaporation+rates.">Development of the new ventilation capsule type sweating-evaporation ratemeter - measurements of local sweating rates and evaporation rates.</a> Tech. Rep. IEICE. 106 (253), 65-68 (2006).</li><li>Ogai, K., Fukuoka, M., Kitamura, K., Uchide, K., Nemoto, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+a+small+wireless+device+for+perspiration+monitoring.">Development of a small wireless device for perspiration monitoring.</a> Med. Eng. Phys. 38 (4), 391-397 (2016).</li><li>Claus, D., Schondorf, R., Deuschl, G., Eisen, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sympathetic+skin+response.">Sympathetic skin response.</a> Recommendations for the Practice of Clinical Neurophysiology Guidelines of the International Federation of Clinical Physiology (EEG Suppl. 52). , 277-282 (1999).</li><li>Emad, M., Roshanzamir, S., Dabbaghmanesh, A., Ghasempoor, M. Z., Eivazlou, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inclusion+of+Height+and+Limb+Length+when+Interpreting+Sympathetic+Skin+Response.">Inclusion of Height and Limb Length when Interpreting Sympathetic Skin Response.</a> Iran J Med Sci. 41 (1), 48-52 (2016).</li></ol>

The author Fukuoka Masakazu is the president of the Rousette Strategy Inc., where the developed device was assembled. No financial support was received from either Fukuoka Masakazu or the Rousette Strategy Inc.

The aim of this article is to introduce the use of a novel, wireless perspiration monitoring device. Owing to the recent progress of engineering, more accurate, easy-to-handle methods for temporal perspiration monitoring have been proposed; the ventilated chamber method24,25 and the vapor pressure diffusion method23 are representative examples. However, the ventilated chamber method requires the use of dry nitrogen or a pump with desiccant to produce a dry atmosphere, and thus, the exterior tends to be large. The vapor pressure diffusion method can be adopted in a small exterior, although the open chamber system can be largely influenced by the outer atmosphere, and the closed chamber system has a problem with either water vapor saturation (the chamber is filled with a saturated water vapor) or considerable power consumption of a water vapor condenser (e.g., Peltier device).
To address the situation, we have recently developed a novel wireless device for perspiration monitoring26. In the device, the water vapor from the skin can be captured by a desiccant, enabling a constant but natural flow. In the course of the water vapor traveling, the T/RH sensor captures the flow of the water vapor as a change in the temperature and relative humidity. By calculating such changes under Fick&#39;s law, we could estimate the temporal changes of perspiration amount (mg/cm2/min) with &#60;5% error, relative to the conventional ventilated chamber method26. The developed device can be used, for example, to monitor mental stress (Figure 2), thermal sweating, and ultimately the perspiration-related dysregulation in an easier manner.
The developed device is easy to handle, and so there are few points to consider. However, the perspiration measurement would fail if the silica gel is not dry. Therefore, before the experiment,&#160;the examiner should make sure that the silica gel is completely dry (i.e.&#160;the color is blue). A previous study has estimated the maximum duration of measurement being longer than 4 hr without changing the silica gel26. To re-nature silica gel, dry it in a drying oven until the color turns blue. A conventional microwave oven is also useful. The perspiration measurement would also fail if the attachment of the device is not sufficient. We recommend the usage of a &#34;doughnut-shaped&#34; double-sided tape.
Nonetheless, the developed device has a limitation. Because of the delicate calculation and the limit of desiccant absorptivity, the error of the amount of perspiration should be considered, especially at the higher level of perspiration. Although we have confirmed the error rate as being &#60;5% relative to the conventional method26, the absolute value of the calculated perspiration value should be handled with caution.
Owing to the small, simple, and wireless design of the device, the multipoint perspiration monitoring under unrestricted conditions can be possible. As shown in Figure 3, the different temporal profiles of perspiration can be detected on the different positions of the skin (i.e.&#160;palm and anterior chest) in daily life conditions (e.g., talking, eating foods, driving a car, shopping, etc.). The device, therefore, might be utilized for the simultaneous detection of abnormal sweating derived both from the mental and thermal regulatory system malfunction. For example, the dysregulation of the peripheral nervous system in diabetes might be detected if the unbalanced sweating between the left and right soles were to be detected. We are now planning an observational study of perspiration profiles in hospitalized patients as a clinical experiment.

Human perspiration, generally known as &#34;sweating,&#34; is not just a mechanism for thermoregulation1, but it is also related to certain kinds of diseases. The etiology of abnormal perspiration is broad, including: heatstroke, hyper- or hypothyroidism2, brain infarction3, diabetes mellitus4, dysautonomia5, menopause (known as &#34;hot flash&#34;)6, cystic fibrosis7, Parkinson&#39;s disease8, and social anxiety disorder9. In light of the number of perspiration-related diseases, it has been considered beneficial to monitor perspiration rates for the early diagnosis or prediction of such diseases (e.g., prevention of heatstroke) in a ubiquitous manner10.
To date, only a small number of devices for perspiration monitoring have been proposed. In early days, skin conductance and relative humidity were used for indirect indices of the amount of perspiration11,12. Most recently, several kinds of flexible, wearable sensors for perspiration monitoring have been proposed13-19, although they are intended for the analysis of sweat electrolytes rather than the amount or temporal pattern of perspiration. The calculation of water vapor diffusion has been utilized for a more quantitative method of monitoring water exchange from the skin20-23. However, this requires (1) the assumption that the outer atmosphere is still and constant20, (2) enough sensitivity to detect the natural flow of water vapor21,22, or (3) a coolant (e.g., Peltier device that consumes a substantial amount of electricity) to condense water vapor to liquid23; thus, they might be difficult for daily and long-term monitoring. As an alternative, a ventilated chamber method was developed20,24,25. In the ventilated chamber method, dry nitrogen or dehumidified air is infiltrated in a small chamber adjacent to the skin from a nitrogen gas tank or a pump, and gas in the water vapor evaporated from the skin is collected. The amount of water vapor from the skin can be calculated from the difference of the humidity in the outlet and inlet gases. Although this method can estimate the amount of perspiration very precisely, a nitrogen gas tank or a mechanical pump is generally large enough to impede daily monitoring.
To address these drawbacks, we have recently developed a novel device for perspiration monitoring, in which a closed chamber with a desiccant-driven enforced water vapor flow, enabled sensitive and long-term monitoring26. This device consists of a cylindrical plastic exterior, temperature/relative humidity (T/RH) sensor with recording microprocessor, and silica gel (Figure 1). In principle, the outer atmosphere should not interfere with the water vapor flow, and a coolant or ventilating chamber is not required. Perspiration profiles can be obtained by solving equations using a spreadsheet software26. A previous study has only shown the principle of the developed device and has omitted the detailed method for how to use the device because of space limitations.
The objective of this article, therefore, is to show a detailed method of how to use the developed device for perspiration monitoring, by showing the recording of stress-induced palmar perspiration during the sympathetic activity test as an example.

<table><tbody><tr><td>Required for perspiration monitoring</td><td></td><td></td><td></td></tr><tr><td>Perspiration monitoring device</td><td>Rousette Strategy Inc.</td><td>SNT-200</td><td></td></tr><tr><td>USB-serial port conversion interface</td><td>Rousette Strategy Inc.</td><td>UUI-200</td><td></td></tr><tr><td>Perspiration recording software</td><td>Rousette Strategy Inc.</td><td>TED99</td><td></td></tr><tr><td>Silica gel</td><td>Wako Pure Chemical Industries Ltd.</td><td>194-16665</td><td>Type A silica gel should be used.</td></tr><tr><td>Medical double-sided tape</td><td>3M</td><td>2181</td><td>Medical grade is recommended because of the attachment to the skin.</td></tr><tr><td>Computer</td><td></td><td></td><td>Requires Windows operating system.</td></tr><tr><td>&lt;strong&gt;Name&lt;/strong&gt;</td><td>&lt;strong&gt;Company&lt;/strong&gt;</td><td>&lt;strong&gt;Catalog&lt;/strong&gt;</td><td>&lt;strong&gt;Comments&lt;/strong&gt;</td></tr><tr><td>&lt;strong&gt;Required for the monitoring of sympathetic skin response&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Instrumentation amplifier</td><td>Nihon Kohden Corp.</td><td>AB-611J</td><td></td></tr><tr><td>Amplifier chassis</td><td>Nihon Kohden Corp.</td><td>MEG-6108</td><td></td></tr><tr><td>Input box</td><td>Nihon Kohden Corp.</td><td>JB-610B</td><td></td></tr><tr><td>Alcohol swab</td><td>Suzuran Sanitary Goods Co., Ltd.</td><td>4545766050846</td><td></td></tr><tr><td>Electrodes</td><td>Nihon Kohden Corp.</td><td>NE-114A</td><td></td></tr><tr><td>Electrode paste</td><td>Nihon Kohden Corp.</td><td>Z-401CE</td><td></td></tr><tr><td>Medical tape</td><td>Nichiban Co., Ltd.</td><td>SG257</td><td></td></tr><tr><td>Analog signal interface</td><td>Micro Science K.K.</td><td>C BOX-014</td><td></td></tr><tr><td>Analog-to-digital converter</td><td>Micro Science K.K.</td><td>ADM-686PCI</td><td></td></tr><tr><td>SSR recording software</td><td>Matsuyama Advance Co., Ltd.</td><td>LaBDAQ2000</td><td></td></tr></tbody></table>

a detailed protocol for perspiration monitoring using a novel, small, wireless device

Perspiration monitoring can be utilized for the detection of certain diseases, such as thermoregulation and mental disorders, particularly when the patients are unaware of such disorders or are having difficulty expressing their symptoms. Until now, several devices for perspiration monitoring have been developed; however, such devices tend to have a relatively large exterior, considerable power consumption, and/or less sensitivity.
Recently, we developed a small, wireless device for perspiration monitoring. The device consists of a temperature/relative humidity (T/RH) sensor, battery-driven small data logger, and silica gel as a desiccant in a small cylindrical exterior. The T/RH sensor is placed between the detection windows (through which the water vapor from the skin enters) and the silica gel. The underlying principle of the perspiration monitoring device is based on Fick&#39;s law of diffusion, which means that water vapor flux from the skin to the silica gel (i.e.&#160;transepidermal water loss and perspiration) can be captured by change in humidity at the T/RH sensor. In addition, a baseline subtraction method was adopted to distinguish perspiration and transepidermal water loss.
As shown in the previous report, the developed device can monitor the perspiration at any sites of the body in an easy, wireless manner. However, detailed methods of how to use the device have not been disclosed yet. In this article, therefore, we would like to show the point-by-point tutorials of how to use the device for perspiration monitoring, by showing the sympathetic activity test with the sympathetic skin response monitoring as an example.

Using this novel device for perspiration monitoring (Figure 1) and the Fick&#39;s law-based calculation, the temporal perspiration profiles can be obtained in an easy, wireless manner. Figure 2 shows representative data of wireless perspiration monitoring during the sympathetic activity test. In the experiment, the device for the perspiration monitoring, along with the electrodes for the sympathetic skin response (SSR) monitoring, was attached to the subject&#39;s palm. For the sympathetic activity test, the subject was requested to sit and perform the following tasks: (1) take a deep inspiration 5 times with 1 min intervals, and (2) do a mental calculation (e.g., continuously subtract 7 from 100, or the &#34;Flash Anzan&#34; in which the participant sums up the number displayed one after the other on a computer screen) to evoke sympathetic activity. The perspiration and the SSR were simultaneously recorded during the stress conditions. As a result of deep inspiration and mental calculation, the sympathetic activity-induced palmar perspiration could be measured using the developed device. Figure 3 shows representative data of multipoint measurement during daily activities. About 1 hr recording of perspiration at the palm (emotional sweating) and the anterior chest (thermal sweating) showed distinct patterns according to the activities.
<img alt="Figure 1" src="/files/ftp_upload/54837/54837fig1.jpg" /> 
Figure 1: The Novel Device for Perspiration Monitoring. (A) The exterior of the device containing dry silica gel. (B, C) A &#34;doughnut-shaped&#34; double-sided tape used in this study and its attachment to the device. (D) Attachment of the device to the skin. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54837/54837fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" src="/files/ftp_upload/54837/54837fig2.jpg" /> 
Figure 2: Representative Recording of Perspiration Under the Sympathetic Activity Test. (A) Attachment of the perspiration monitoring device with the sympathetic skin response (SSR) electrodes on the palm. (B) As a result of sympathetic activity test, palmar perspiration along with the SSR reaction was observed in response to the sympathetic activities. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54837/54837fig2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 3" src="/files/ftp_upload/54837/54837fig3.jpg" /> 
Figure 3: Representative Multipoint Recording of Perspiration During the Daily Activities. The distinct patterns of perspiration according to the different parts of the body (red line, at the palm; blue line, at the anterior chest) were observed during several activities (e.g., going downstairs, driving a car, having a lunch with talking, and shopping). <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54837/54837fig3large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

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A Detailed Protocol for Perspiration Monitoring Using a Novel, Small, Wireless Device

Recently, we developed a small wireless device for perspiration monitoring. In this article, we present detailed protocols on how to use the device for perspiration monitoring with an example of the sympathetic activity test.

Perspiration monitoring can be utilized for the detection of certain diseases, such as thermoregulation and mental disorders, particularly when the ...

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Nanyang Technological University

Research

JoVE Journal

Medicine

7.8K Views.  Kanazawa University. Recently, we developed a small wireless device for perspiration monitoring. In this article, we present detailed protocols on how to use the device for perspiration monitoring with an example of the sympathetic activity test.

Video: A Detailed Protocol for Perspiration Monitoring Using a Novel, Small, Wireless Device

Use of Galvanic Skin Responses, Salivary Biomarkers, and Self-reports to Assess Undergraduate Student Performance During a Laboratory Exam Activity

Typically, self-reports are used in educational research to assess student response and performance to a classroom activity. Yet, addition of biological and physiological measures such as salivary biomarkers and galvanic skin responses are rarely included, limiting the wealth of information that can be obtained to better understand student performance. A laboratory protocol to study undergraduate students&#39; responses to classroom events (e.g., exams) is presented. Participants were asked to complete a representative exam for their degree. Before and after the laboratory exam session, students completed an academic achievement emotions self-report and an interview that paralleled these questions when participants wore a galvanic skin sensor and salivary biomarkers were collected. Data collected from the three methods resulted in greater depth of information about students&#39; performance when compared to the self-report. The work can expand educational research capabilities through more comprehensive methods for obtaining nearer to real-time student responses to an examination activity.

Research on undergraduate students' academic achievement emotions have primarily relied on self-reports in laboratory settings. Studies rarely include bio-physiological measures to these self-reports. This protocol will describe a methodology that integrates self-reports with and bio-physiological measures to assess student response and performance during a laboratory examination activity.

Typically, self-reports are used in educational research to assess student response and performance to a classroom activity. Yet, addition of biological ...

Behavior

A Community-based Stress Management Program: Using Wearable Devices to Assess Whole Body Physiological Responses in Non-laboratory Settings

A pragmatic breath-based intervention to benefit human performance and stress management is timely and valuable to individuals seeking holistic approaches for emotional regulation and optimizing compensatory reserve mechanisms. This protocol is designed to not only teach mind-body awareness but also to provide feedback utilizing physiological data and survey results. The primary findings of this study showed that heart coherence and alpha variables were significantly correlated after four weeks of the breath-based meditation stress protocol. Meditation and rhythmic breathing produced significant increases in alpha brain activity. These brain physiological responses conformed to the Pleth Variability Index (PVI) changes, suggesting the ability of the human body to enter into a meditative state and effectively manage stress. When assessed after four weeks of daily practicing the techniques employed in the stress management protocol, based on the Five Facet Mindfulness Questionnaire, subjects improved in applying mindfulness skills. The overall mindfulness score, Pleth variability index (PVI), and perfusion index (PI) increased after the 4-week intervention period. Results from electroencephalography (brain waves) were consistent with a meditative state during the post-study follow-up session. This provides evidence that wearable devices are feasible for data collection during a breath-based stress management intervention. This protocol can be easily and efficiently implemented into any study design in which physiological data are desired in a non-laboratory-based setting.

Stress is an unavoidable and persistent component of life and holistic approaches for its management are being considered. A standardized methodology was created to demonstrate the feasibility of a breath-based stress management protocol that can be used with commercially available portable technology.

A pragmatic breath-based intervention to benefit human performance and stress management is timely and valuable to individuals seeking holistic approaches ...

Methodology for Establishing a Community-Wide Life Laboratory for Capturing Unobtrusive and Continuous Remote Activity and Health Data

An end-to-end suite of technologies has been established for the unobtrusive and continuous monitoring of health and activity changes occurring in the daily life of older adults over extended periods of time. The technology is aggregated into a system that incorporates the principles of being minimally obtrusive, while generating secure, privacy protected, continuous objective data in real-world (home-based) settings for months to years. The system includes passive infrared presence sensors placed throughout the home, door contact sensors installed on exterior doors, connected physiological monitoring devices (such as scales), medication boxes, and wearable actigraphs. Driving sensors are also installed in participants' cars and computer (PC, tablet or smartphone) use is tracked. Data is annotated via frequent online self-report options that provide vital information with regard to the data that is difficult to infer via sensors such as internal states (e.g., pain, mood, loneliness), as well as data referent to activity pattern interpretation (e.g., visitors, rearranged furniture). Algorithms have been developed using the data obtained to identify functional domains key to health or disease activity monitoring, including mobility (e.g., room transitions, steps, gait speed), physiologic function (e.g., weight, body mass index, pulse), sleep behaviors (e.g., sleep time, trips to the bathroom at night), medication adherence (e.g., missed doses), social engagement (e.g., time spent out of home, time couples spend together), and cognitive function (e.g., time on computer, mouse movements, characteristics of online form completion, driving ability). Change detection of these functions provides a sensitive marker for the application in health surveillance of acute illnesses (e.g., viral epidemic) to the early detection of prodromal dementia syndromes. The system is particularly suitable for monitoring the efficacy of clinical interventions in natural history studies of geriatric syndromes and in clinical trials.

Unobtrusive sensors and pervasive computing technology incorporated into the daily home life of older adults enables meaningful health and activity changes to be recorded continuously for months to years, providing ecologically valid, high frequency, multi-domain data for research or clinical use.

An end-to-end suite of technologies has been established for the unobtrusive and continuous monitoring of health and activity changes occurring in the ...

A Novel Digital Platform for a Monitored Home-based Cardiac Rehabilitation Program

Despite the evidence that cardiac rehabilitation (CR) reduces the risk of recurrent cardiac events, only a minority of eligible patients are willing to join existing programs at cardiac rehabilitation centers. The unique remote patient monitoring system presented here enables healthcare providers to monitor CR patients at home in real-time and at low cost. The system combines mobile technology, artificial intelligence, and supportive services, expanding the delivery of medical care to the patient&#39;s home. The primary aim of the study is to increase the long-term adherence to physical activity in patients who participate in CR via the addition of a home-based digitally monitored CR component to the standard CR program in patients with ischemic heart disease (IHD), with the idea of forming new habitual health behaviors and increasing the long-term motivation for physical exercise (PE) habits at home. Secondary aims are to assess the program&#39;s impact on the physical activity level measured by average steps per day, minutes of exercise per week, blood pressure, metabolic parameters, body mass index, and waist-to-hip ratio, as well as a quality-of-life (QoL) questionnaire.The study has two arms: (1) home-based monitored exercise using a smart digital garment and wristband, in addition to motivation and reinforcement via text messages; (2) standard CR facility-based exercise. The study design is a randomized, controlled trial comparing standard CR to a home-based monitoring and reinforcement program. The study program is designed for 12 weeks.Clinical tests and anthropometric measurements are performed before and after the study, measuring height, weight, waist circumference, visceral fat and body mass index (BMI), blood pressure, and HbA1c and lipid profile. Patients have to complete a baseline survey including socio-demographic characteristics and QoL questionnaire SF-36. At the end of the study, patients complete a survey regarding the use of the smart digital garment&#39;s benefits and usability. The study is currently underway.

The aim is to promote a new approach to cardiac rehabilitation (CR), using a unique remote patient monitoring system that will enable healthcare providers to monitor CR patients at home at low cost, with the intention of making CR services more accessible and improving compliance. The study is currently underway.

Despite the evidence that cardiac rehabilitation (CR) reduces the risk of recurrent cardiac events, only a minority of eligible patients are willing to ...

Evaluation of Commercial-Off-The-Shelf Wrist Wearables to Estimate Stress on Students

Wearable commercial-off-the-shelf (COTS) devices have become popular during the last years to monitor sports activities, primarily among young people. These devices include sensors to gather data on physiological signals such as heart rate, skin temperature or galvanic skin response. By applying data analytics techniques to these kinds of signals, it is possible to obtain estimations of higher-level aspects of human behavior. In the literature, there are several works describing the use of physiological data collected using clinical devices to obtain information on sleep patterns or stress. However, it is still an open question whether data captured using COTS wrist wearables is sufficient to characterize the learners' psychological state in educational settings. This paper discusses a protocol to evaluate stress estimation from data obtained using COTS wrist wearables. The protocol is carried out in two phases. The first stage consists of a controlled laboratory experiment, where a mobile app is used to induce different stress levels in a student by means of a relaxing video, a Stroop Color and Word test, a Paced Auditory Serial Addition test, and a hyperventilation test. The second phase is carried out in the classroom, where stress is analyzed while performing several academic activities, namely attending to theoretical lectures, doing exercises and other individual activities, and taking short tests and exams. In both cases, both quantitative data obtained from COTS wrist wearables and qualitative data gathered by means of questionnaires are considered. This protocol involves a simple and consistent method with a stress induction app and questionnaires, requiring a limited participation of support staff.

A protocol to evaluate solutions based on commercial-off-the-shelf (COTS) wrist wearables to estimate stress in students is proposed. The protocol is carried out in two phases, an initial laboratory-based stress induction test, and a monitoring stage taking place in the classroom while the student is performing academic activities.

Wearable commercial-off-the-shelf (COTS) devices have become popular during the last years to monitor sports activities, primarily among young people. ...

Engineering

An Application for Pairing with Wearable Devices to Monitor Personal Health Status

The current protocol aims to showcase the technology integration, providing a detailed description of adopting the HealthCloud app, developed by the Healthy Landscape and Healthy People Lab, National Taiwan University (HLHP-NTU), on smartphones and smartwatches to collect data on users' real-time psychological and physiological responses and environmental information. A flexible and integrated research method was proposed because it can be difficult to measure multi-dimensional aspects of personal data in on-site studies in landscape and outdoor recreation research. An on-site study conducted in 2020 at the National Taiwan University campus was used as an application example. A dataset of 385 participants was used after excluding invalid samples. During the experiment, participants were asked to walk around campus for 30 min when their heart rate and psychological-scale items were measured, together with several environmental metrics. This work aimed to provide a possible solution to help on-site studies track real-time human responses that match ambient factors. Due to the app's flexibility, its use on wearable devices shows excellent potential for multidisciplinary research studies.

The present protocol introduces a non-commercial self-developed application for collecting real-time on-site data, including psychological scales, GPS location, heart rate, and blood-oxygen saturation level, as well as the application's operating procedures. An empirical study conducted in Taiwan in 2020 was used as an application example.

The current protocol aims to showcase the technology integration, providing a detailed description of adopting the HealthCloud app, developed by the ...

Environment

Fabrication and Characterization of a Conformal Skin-like Electronic System for Quantitative, Cutaneous Wound Management

Recent advances in the development of electronic technologies and biomedical devices offer opportunities for non-invasive, quantitative assessment of cutaneous wound healing on the skin. Existing methods, however, still rely on visual inspections through various microscopic tools and devices that normally include high-cost, sophisticated systems and require well trained personnel for operation and data analysis. Here, we describe methods and protocols to fabricate a conformal, skin-like electronics system that enables conformal lamination to the skin surface near the wound tissues, which provides recording of high fidelity electrical signals such as skin temperature and thermal conductivity. The methods of device fabrication provide details of step-by-step preparation of the microelectronic system that is completely enclosed with elastomeric silicone materials to offer electrical isolation. The experimental study presents multifunctional, biocompatible, waterproof, reusable, and flexible/stretchable characteristics of the device for clinical applications. Protocols of clinical testing provide an overview and sequential process of cleaning, testing setup, system operation, and data acquisition with the skin-like electronics, gently mounted on hypersensitive, cutaneous wound and contralateral tissues on patients.

This article presents methods to fabricate and characterize a conformal, skin-like electronic system and protocols for the use in clinical applications, particularly on cutaneous wound management.

Recent advances in the development of electronic technologies and biomedical devices offer opportunities for non-invasive, quantitative assessment of ...

Bioengineering

Home-Based Monitor for Gait and Activity Analysis

Current outcomes in neuromuscular disorder clinical trials include motor function scales, timed tests, and strength measures performed by trained clinical evaluators. These measures are slightly subjective and are performed during a visit to a clinic or hospital and constitute therefore a point assessment. Point assessments can be influenced by daily patient condition or factors such as fatigue, motivation, and intercurrent illness. To enable home-based monitoring of gait and activity, a wearable magneto-inertial sensor (WMIS) has been developed. This device is a movement monitor composed of two very light watch-like sensors and a docking station. Each sensor contains a tri-axial accelerometer, gyroscope, magnetometer, and a barometer that record linear acceleration, angular velocity, the magnetic field of the movement in all directions, and barometric altitude, respectively. The sensors can be worn on the wrist, ankle, or wheelchair to record the subject&#8217;s movements during the day. The docking station enables data uploading and recharging of sensor batteries during the night. Data are analyzed using proprietary algorithms to compute parameters representative of the type and intensity of the performed movement. This WMIS can record a set of digital biomarkers, including cumulative variables, such as total number of meters walked, and descriptive gait variables, such as the percentage of the most rapid or longest stride that represents the top performance of patient over a predefined period of time.

This innovative device uses magneto-inertial sensors to permit gait and activity analysis in uncontrolled environments. Currently in the qualification process as an outcome measure in the European Medical Agency, one of the applications will be to serve as a clinical endpoint in clinical trials in neuromuscular diseases.

Current outcomes in neuromuscular disorder clinical trials include motor function scales, timed tests, and strength measures performed by trained clinical ...

Conformable Wearable Electrodes: From Fabrication to Electrophysiological Assessment

Wearable electronic devices are becoming key players in monitoring the body signals predominantly altered during physical activity tracking. Considering the growing interest in telemedicine and personalized care driven by the rise of the Internet of Things era, wearable sensors have expanded their field of application into healthcare. To ensure the collection of clinically relevant data, these devices need to establish conformable interfaces with the human body to provide high-signal-quality recordings and long-term operation. To this end, this paper presents a method to easily fabricate conformable thin tattoo- and soft textile-based sensors for their application as wearable organic electronic devices in a broad spectrum of surface electrophysiological recordings. 
The sensors are developed through a cost-effective and scalable process of cutaneous electrode patterning using poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS), the most popular conductive polymer in bioelectronics, on off-the-shelf, wearable substrates. This paper presents key steps in electrode characterization through impedance spectroscopy to investigate their performance in signal transduction when coupled with the skin. Comparative studies are required to position the performance of novel sensors with respect to the clinical gold standard. To validate the fabricated sensors' performance, this protocol shows how to perform various biosignal recordings from different configurations through a user-friendly and portable electronic setup in a laboratory environment. This methods paper will allow multiple experimental initiatives to advance the current state of the art in wearable sensors for human body health monitoring.

Two recent technologies-tattoo and textiles-have demonstrated promising results in cutaneous sensing. Here, we present the fabrication and evaluation methods of tattoo and textile electrodes for cutaneous electrophysiological sensing. These electronic interfaces made of conductive polymers outperform the existing standards in terms of comfort and sensitivity.

Wearable electronic devices are becoming key players in monitoring the body signals predominantly altered during physical activity tracking. Considering ...

Setup of Consumer Wearable Devices for Exposure and Health Monitoring in Population Studies

Wearable sensors, which are often embedded in commercial smartwatches, allow for continuous and non-invasive health measurements and exposure assessments in clinical studies. Nevertheless, the real-life application of these technologies in studies involving a large number of participants for a significant observation period may be hindered by several practical challenges. 
In this study, we present a modified protocol from a previous intervention study for the mitigation of health effects from desert dust storms. The study involved two distinct population groups: asthmatic children aged 6-11 years and elderly patients with atrial fibrillation (AF). Both groups were equipped with a smartwatch for the assessment of physical activity (using a heart rate monitor, pedometer, and accelerometer) and location (using GPS signals to locate individuals in indoor "at home" or outdoor microenvironments). The participants were required to wear the smartwatch equipped with a data collection application on a daily basis, and data were transmitted via a wireless network to a centrally administered data collection platform for the near real-time assessment of compliance. 
Over a period of 26 months, more than 250 children and 50 patients with AF participated in the aforementioned study. The main technical challenges identified included restricting access to standard smartwatch features, such as gaming, internet browser, camera, and audio recording applications, technical issues, such as loss of GPS signal, especially in indoor environments, and the internal smartwatch settings interfering with the data collection application.
The aim of this protocol is to demonstrate how the use of publicly available application lockers and device automation applications made it possible to address most of these challenges in a simple and cost-effective way. In addition, the inclusion of a Wi-Fi received signal strength indicator significantly improved indoor localization and largely minimized GPS signal misclassification. The implementation of these protocols during the roll-out of this intervention study in the spring of 2020 led to significantly improved results in terms of data completeness and data quality.

Commercial smartwatches equipped with wearable sensors are increasingly being used in population studies. However, their utility is often constrained by their limited battery duration, memory capacity, and data quality. This report provides examples of cost-effective solutions to real-life technical challenges encountered during studies involving asthmatic children and elderly cardiac patients.

Wearable sensors, which are often embedded in commercial smartwatches, allow for continuous and non-invasive health measurements and exposure assessments ...