Recent studies have developed simple techniques for monitoring and assessing sleep. However, several issues remain to be solved for example high-cost sensor and algorithm as a home-use device. In this study, we aimed to develop an inexpensive and simple sleep monitoring system using a camera and video processing. Polysomnography (PSG) recordings were performed in six subjects for four consecutive nights. Subjects' body movements were simultaneously recorded by the web camera. Body movement was extracted by video processing from the video data and fi ve parameters were calculated for machine learning. Four sleep stages (WAKE, LIGHT, DEEP and REM) were estimated by applying these fi ve parameters to a support vector machine. The overall estimation accuracy was 70.3 ± 11.3% with the highest accuracy for DEEP (82.8 ± 4.7%) and the lowest for LIGHT (53.0 ± 4.0%) compared with correct sleep stages manually scored on PSG data by a sleep technician. Estimation accuracy for REM sleep was 68.0 ± 6.8%. The kappa was 0.19 ± 0.04 for all subjects. The present non-contact sleep monitoring system showed suffi cient accuracy in sleep stage estimation with REM sleep detection being accomplished. Low-cost computing power of this system can be advantageous for mobile application and modularization into home-device.
Machine Learning ; Methods ; Mobile Applications ; Polysomnography ; Sleep Stages ; Sleep, REM ; Support Vector Machine

Introduction: We analyzed the concentrations of the trace elements [chromium (Cr), arsenic (As), cadmium (Cd), cesium (Cs), lead (Pb), thorium (Th), and uranium (U)] in commercial bottled water consumed in the town of Angono, Rizal province, Luzon island, Philippines to evaluate the health risks of the trace elements in drinking water. There are some arguments that water resources available in the Philippines are heavily polluted by various materials, inparticular heavy metal elements. Method: The concentrations of seven trace elements in commercial bottled water produced and consumed in the Philippines were analyzed using a solution nebulization inductively coupled plasma mass spectrometry (SN−ICP−MS). Result: The concentrations of the trace elements except for Cs, which does not yet have a WHO guideline value, in the locally produced bottled water were below the WHO guideline values. The Cs concentrations (<0.6 μg/L) of the bottled water of the Philippines were generally similar to those of the bottled water produced and consumed in other countries such as Japan, China, and Indonesia. Conclusion The concentrations of trace elements in bottled water consumed in Angono, Philippines can be regarded as being at safe levels, as well as those of daily life water (i.e. tap, well, and spring water) consumed in the said town.
Drinking Water ; Trace Elements ; Philippines

Objective: The present study aims to determine the concentrations of seven trace elements [chromium (Cr), arsenic (As), cadmium (Cd), cesium (Cs), lead (Pb), thorium (Th), and uranium (U)] in tap, well, spring, river, and lake waters in the town of Angono, Rizal in the Philippines, consumed for drinking, cooking, bathing, and washing. In the town of Angono, both of the tap and purified tap waters produced in the refilling station are consumed as the water for drinking. Methods: Water samples from six unpurified tap, six purified taps, 10 wells, two springs, two rivers, and one lake water were obtained in October 2015. Samples were analyzed using solution nebulization inductively coupled plasma mass spectrometry. Results were evaluated for health risks of the trace elements in the water samples using WHO guideline values. The provisional WHO guideline values are as follows: Cr: 50 μg/L, As: 10 μg/L, Cd: 3 μg/L, Pb: 10 μg/L, and U: 30 μg/L. That of Cs has not been proposed yet. The WHO guideline value for the naturally occurring radioactive isotope 232Th in drinking water is 1 Bq/L, which is equivalent to 250 μg/L. Results: The concentrations of the trace elements in the tap water samples were <0.5% of the WHO guideline values, except Cs and Cd, with those of Cd being ~9% of the WHO guideline value. Purified tap waters contained the seven trace elements in lower concentrations, with the exception of Pb, which may have been added in small amounts from equipment used for water purification. The concentrations of the trace elements in water samples from the wells and springs in Angono were more variable than those of the tap waters, and these were also below the WHO guideline values. The concentrations of Cs in all water samples were <0.3 μg/L. The trace-element concentrations of the waters from Angono River and Laguna Lake were almost the same as those of the well and spring waters. Conclusion At present, the concentrations of trace elements in daily life water consumed in Angono are at safe levels.
Trace Elements