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Background: Exercise has shown to slow down the progression from mild cognitive impairment (MCI) to dementia. In particular, not only resistance exercise has been verified to improve physical performance and muscle strength, leading to the prevention of fall-related injuries in the frail elderly, but also cognitive function. In this study, we investigated how high-speed elastic band training, applied using a high-speed power training protocol, affects cognition, physical performance and muscle strength of female elderly individuals with MCI. Methods: Thirty-nine subjects diagnosed with MCI from one senior college using a Korean version of mini-mental state examination (MMSE-K) and a Korean version of the Montreal Cognitive Assessment (MoCA-K) were randomly divided into exercise group (n=20) and control group (n=19). The exercise group completed a 12-week high-speed resistance elastic band exercise program and was encouraged to exercise at home as well during the intervention period. Results:The results showed significant increases in cognitive function, physical performance and muscle strength assessed by digit span forward test (P<0.001), digit span backward test (P=0.003), the Stroop test B (P=0.031), SPPB scores (P=0.010), right knee 60° extensor peak torque (P=0.004), 60° flexor peak torque (P=0.001), 180° extensor peak torque (P=0.020) and grip strength (P=0.025) Conclusions: Our study showed that participants with MCI who continued the high-speed elastic band training program for 12 weeks showed improvements in cognitive function, physical performance and muscle strength.

Ultra-wideband (UWB) wireless communication is prospering as a powerful partner of the Internet-of-things (IoT). Due to the ongoing development of UWB wireless communications, the demand for high-speed and medium resolution analog-to-digital converters (ADCs) continues to grow. The successive approximation register (SAR) ADCs are the most powerful candidate to meet these demands, attracting both industries and academia. In particular, recent time-interleaved SAR ADCs show that multi-giga sample per second (GS/s) can be achieved by overcoming the challenges of high-speed implementation of existing SAR ADCs. However, there are still critical issues that need to be addressed before the time-interleaved SAR ADCs can be applied in real commercial applications. The most well-known problem is that the time-interleaved SAR ADC architecture requires multiple sub-ADCs, and the mismatches between these sub-ADCs can significantly degrade overall ADC performance. And one of the most difficult mismatches to solve is the sampling timing skew. Recently, research to solve this timing-skew problem has been intensively studied. In this paper, we focus on the cutting-edge timing-skew calibration technique using a window detector. Based on the pros and cons analysis of the existing techniques, we come up with an idea that increases the benefits of the window detector-based timing-skew calibration techniques and minimizes the power and area overheads. Finally, through the continuous development of this idea, we propose a timing-skew calibration technique using a comparator offset-based window detector. To demonstrate the effectiveness of the proposed technique, intensive works were performed, including the design of a 7-bit, 2.5 GS/s 5-channel time-interleaved SAR ADC and various simulations, and the results prove excellent efficacy of signal-to-noise and distortion ratio (SNDR) and spurious-free dynamic range (SFDR) of 40.79 dB and 48.97 dB at Nyquist frequency, respectively, while the proposed window detector occupies only 6.5% of the total active area, and consumes 11% of the total power.