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There is an increasing need to develop flexible, reconfigurable, and intelligent low power wireless sensor network (WSN) system for healthcare applications. Technical advancements in micro-sensors, MEMS devices, low power electronics, and radio frequency circuits have enabled the design and development of such highly integrated system. In this paper, we present our proposed wireless thermal sensor network system, which is separated into control and data paths. Both of these paths have their own transmission frequencies. The control path sends the power and function commands from computer to each sensor elements by 2.4GHz RF circuits and the data path transmits measured data by 2.4GHz in sensor layer and 60GHz in higher layers. This hierarchy architecture would make reconfigurable mapping and pipeline applications on WSN possibly, and the average power consumption can be efficiently reduced about 60% by using the adaptive technique.

A novel biomedical acquisition system which can adjust its resolution by the condition of signal is presented in this paper. The resolution of sigma-delta modulator in proposed system can be automatically varied by switching its architecture and sampling rate that can acquire accurate date without additional power consumption. The modulator in this system reaches specifications from 10-bit to 16-bit resolution and consumes power from 48microW to 360microW. In the electrocardiogram and electroculogram acquisition by proposed system, it can save more than 40% and 73% power consumption comparing with the conventional acquisition system.

A sigma-delta modulator which can improve the linearity of input original signal is proposed in this paper. The inverting and double sampling techniques are used in proposed modulator to convert the single-ended signal to fully differential signal. Therefore, the signal's linearity could be modified by the suppression of the even mode harmonic in fully differential circuit. With the proposed technique, the sensing biomedical signals could be more accurately acquired. The proposed modulator is designed in standard 0.18 microm 1P6M CMOS technology. The simulation results show that the linear errors of the CMOS thermal sensor and the PH electrochemical sensor are improved from 42.5% to 20.17%, 8.06% to 3.11%.

Patients with Andersen-Tawil syndrome (ATS) mostly have mutations on the KCNJ2 gene, producing loss of function or dominant-negative suppression of the inward rectifier K(+) channel Kir2.1. However, clinical manifestations of ATS including dysmorphic features, periodic paralysis (hypo-, hyper-, or normokalemic), long QT, and ventricular arrhythmias (VAs) are considerably variable. Using a modified dynamic Luo-Rudy simulation model of cardiac ventricular myocytes, we attempted to elucidate mechanisms of VA in ATS by analyzing effects of the inward rectifier K(+) channel current (I(K1)) on the action potential (AP). During pacing at 1.0 Hz with extracellular K(+) concentration ([K(+)](o)) at 4.5 mM, a stepwise 10% reduction of Kir2.1 channel conductance progressively prolonged the terminal repolarization phase of the AP along with gradual depolarization of the resting membrane potential (RMP). At 90% reduction, early afterdepolarizations (EADs) became inducible and RMP was depolarized to -52.0 mV (control: -89.8 mV), followed by emergence of spontaneous APs. Both EADs and spontaneous APs were facilitated by a decrease in [K(+)](o) and suppressed by an increase in [K(+)](o). Simulated beta-adrenergic stimulation enhanced delayed afterdepolarizations (DADs) and could also facilitate EADs as well as spontaneous APs in the setting of low [K(+)](o) and reduced Kir2.1 channel conductance. In conclusion, the spectrum of VAs in ATS may include 1) triggered activity mediated by EADs and/or DADs and 2) abnormal automaticity manifested as spontaneous APs. These VAs can be aggravated by a decrease in [K(+)](o) and beta-adrenergic stimulation and may potentially induce torsade de pointes and cause sudden death. In patients with ATS, the hypokalemic form of periodic paralysis should have the highest propensity to VAs, especially during physical activity.

This paper presents an innovative portable chip-based RT-PCR system for amplification of specific nucleic acid and detection of RNA-based viruses. The miniature RT-PCR chip is fabricated using MEMS (Micro-electro-mechanical-system) techniques, and comprises a micro temperature control module and a PDMS (polydimethylsiloxane)-based microfluidic control module. The heating and sensing elements of temperature control module are both made of platinum and are located within the reaction chambers in order to generate a rapid and uniform thermal cycling. The microfluidic control module is capable of automating testing process with minimum human intervention. In this paper, the proposed miniature RT-PCR system is used to amplify and detect two RNA-based viruses, namely dengue virus type-2 and enterovirus 71 (EV 71). The experimental data confirm the ability of the system to perform a two-step RT-PCR process. The developed miniature system provides a crucial tool for the diagnosis of RNA-based viruses.

This paper presents a micro polymerase chain reaction (PCR) chip for the DNA-based diagnosis of microorganism genes and the detection of their corresponding antibiotic-resistant genes. The micro PCR chip comprises cheap biocompatible soda-lime glass substrates with integrated thin-film platinum resistors as heating/sensing elements, and is fabricated using micro-electro-mechanical-system (MEMS) techniques in a reliable batch-fabrication process. The heating and temperature sensing elements are made of the same material and are located inside the reaction chamber in order to ensure a uniform temperature distribution. This study performs the detection of several genes associated with upper respiratory tract infection microorganisms, i.e. Streptococcus pneumoniae, Haemopilus influenze, Staphylococcu aureus, Streptococcus pyogenes, and Neisseria meningitides, together with their corresponding antibiotic-resistant genes. The lower thermal inertia of the proposed micro PCR chip relative to conventional bench-top PCR systems enables a more rapid detection operation with reduced sample and reagent consumption. The experimental data reveal that the high heating and cooling rates of the system (20 and 10 degrees C/s, respectively) permit successful DNA amplification within 15 min. The micro PCR chip is also capable of performing multiple DNA amplification, i.e. the simultaneous duplication of multiple genes under different conditions in separate reaction wells. Compared with the large-scale PCR system, it is greatly advantageous for fast diagnosis of multiple infectious diseases. Multiplex PCR amplification of two DNA segments in the same well is also feasible using the proposed micro device. The developed micro PCR chip provides a crucial tool for genetic analysis, molecular biology, infectious disease detection, and many other biomedical applications.

Some physically-disabled people with neuromuscular diseases such as amyotrophic lateral sclerosis, multiple sclerosis, muscular dystrophy, or other conditions that hinder their ability to write, type, and speak, require an assistive tool for purposes of augmentative and alternative communication in their daily lives. In this paper, we designed and implemented a wireless environmental control system using Morse code as an adapted access communication tool. The proposed system includes four parts: input-control module; recognition module; wireless-control module; and electronic-equipment-control module. The signals are transmitted using adopted radio frequencies, which permits long distance transmission without space limitation. Experimental results revealed that three participants with physical handicaps were able to gain access to electronic facilities after two months' practice with the new system.