Wearable biomedical monitoring system using TextileNet

金沢大学理工研究域電子情報学系We developed and tested a biomedical monitoring system using TextileNet, a flexible conductive garment for wearable computing. TextileNet detects biological signals while simplifying communication and power supply wiring. TextileNet also acts as an electromagnetic interference (EMI) shield, which makes it possible to use simpler amplifiers in the system. Using TextileNet, a huge amount of biological information can be processed simultaneously. © 2006 IEEE

Wearable electromyography measurement system using cable-free network system on conductive fabric

金沢大学大学院自然科学研究科情報システムObjective: To solve the complicated wires and battery maintenance problems in the application of wearable computing for biomedical monitoring, the electromyography (EMG) measurement system using conductive fabric for power supply and electric shield for noise reduction is proposed. Material and methods: The basic cable-free network system using conductive fabric, named as "TextileNet" is developed. The conductive fabric has the function of electric shield for noise reduction in EMG measurement, and it enables the precise EMG measurement with wearable system. Results: The specifications of the developed prototype TextileNet system using wear with conductive fabric were communication speed of 9600 bit/s and power supply of 3 W for each device. The electric shield effect was evaluated for precise EMG measurement, and the shield efficacy of conductive fabric was estimated as high as that of shield room. Conclusions: TextileNet system solves both the problems of complicated wires and battery maintenance in wearable computing systems. Conductive fabric used in TextileNet system is also effective for precise EMG measurement as electric shield. The combination of TextileNet system and EMG measurement device will implement the cable-free, battery-free wearable EMG measurement system. © 2007 Elsevier B.V. All rights reserved

Selective Stimulation of a Target Neuron in Micropatterned Neuronal Circuits Using a Pair of Needle Electrodes

Neurostimulation is an essential technique to trigger and modulate the spatiotemporal activity of local neuronal circuits. Current stimulation methods have a trade-off relationship among aiming precision, temporal resolution, and noninvasiveness, making it difficult to stimulate and monitor a single target neuron for a long term. Here, we show that a method using two needle electrodes in combination of micropatterning techniques provides new possibilities for targeting and stimulating a single neuron selectively. Results of physiological experiments as well as analog circuit simulation reveal that two needle electrodes can stimulate a target neuron selectively by placing the two needle electrodes in proximity to and to straddle the target neuron, and that the steepness of voltage applied to two needle electrodes is important for the target neuron to fire at a low voltage. The proposed method enables a noninvasive stimulation suitable for measuring long-term activity of local neuronal circuits

Microbial decomposition of biodegradable plastics on the deep-sea floor

Abstract Microbes can decompose biodegradable plastics on land, rivers and seashore. However, it is unclear whether deep-sea microbes can degrade biodegradable plastics in the extreme environmental conditions of the seafloor. Here, we report microbial decomposition of representative biodegradable plastics (polyhydroxyalkanoates, biodegradable polyesters, and polysaccharide esters) at diverse deep-sea floor locations ranging in depth from 757 to 5552 m. The degradation of samples was evaluated in terms of weight loss, reduction in material thickness, and surface morphological changes. Poly(l-lactic acid) did not degrade at either shore or deep-sea sites, while other biodegradable polyesters, polyhydroxyalkanoates, and polysaccharide esters were degraded. The rate of degradation slowed with water depth. We analysed the plastic-associated microbial communities by 16S rRNA gene amplicon sequencing and metagenomics. Several dominant microorganisms carried genes potentially encoding plastic-degrading enzymes such as polyhydroxyalkanoate depolymerases and cutinases/polyesterases. Analysis of available metagenomic datasets indicated that these microorganisms are present in other deep-sea locations. Our results confirm that biodegradable plastics can be degraded by the action of microorganisms on the deep-sea floor, although with much less efficiency than in coastal settings