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This paper presents a low-power, energy-efficient, 12-bit incremental zoom analog-to-digital converter (ADC) for multi-channel bio-signal acquisitions. The ADC consists of a 7-stage ring voltage-controlled oscillator (VCO)-based incremental ΔΣ modulator (I-ΔΣM) and an 8-bit successive approximation register (SAR) ADC. The proposed VCO-based I-ΔΣM can provide fast phase-alignment of the ring-VCO to reduce the interval settling time; thereby, the I-ΔΣM can accommodate time-division-multiplexed input signals without phase leakage between consecutive measurements. The SAR ADC also adopts splitting unit capacitors that can support VCM-free tri-level switching and prevent invalid states from the phase frequency detector with minimal logic gates and switches. The proposed ADC has been fabricated in a standard 180 nm standard 1P6M CMOS process, exhibiting a 67-dB peak signal-to-noise ratio, a 74-dB dynamic range, and a Walden figure of merit of 19.12 fJ/c-s, while consuming a power of 3.51 μW with a sampling rate of 100 kS/s. [ABSTRACT FROM AUTHOR]

The prevalence of behavioral inhibition in toddlers was examined in five cultures. Participants in this study included 110 Australian, 108 Canadian, 151 Chinese, 104 Italian, and 113 South Korean toddlers and their mothers who were observed during a structured observational laboratory session. Matched procedures were used in each country, with children encountering an unfamiliar stranger with a truck and a robot. Indicators of inhibition included the length of time toddlers delayed before approaching the stranger and the duration of contact with their mother while the stranger was in the room. Results were generally consistent with expectations and showed differences between eastern and western cultures; Italian and Australian toddlers were less inhibited than toddlers from the other countries, whereas Chinese and South Korean toddlers were more inhibited. The implications of these findings are discussed and a research agenda for further exploration of inhibition is outlined. (Contains 4 tables.)

South Korean mothers' reactions to preschoolers' aggression and social withdrawal were examined within a cultural framework. With recent social, political, and cultural changes in South Korea, there appears to be a conflict between traditional values and the Confucian heritage on one hand, and Western influence on the other. Mothers (N=81) of preschoolers from Seoul reported their emotional reactions, causal attributions, socialization strategies, and socialization goals that were endorsed in response to these behaviors. Mothers reacted with negative emotions to both child aggression and social withdrawal, with more anger, disgust and embarrassment for aggression. Mothers also believed that aggression was due to external causes, and less stable than social withdrawal. High-powered and directive strategies were provided more often in response to aggression than social withdrawal, whereas lower-powered/indirect strategies were favored for social withdrawal over aggression. Finally, mothers were more likely to suggest parent- and social-centered goals for aggression, and child-centered goals for social withdrawal, indicating the increasing influence of westernized child developmental information on South Korean mothers. The significance of changing cultural norms and conventions in South Korean mothers' perceptions and evaluations of maladaptive behaviors in children was supported.

The purpose of the present study was to examine the proactive socialisation beliefs (goals, attributions, strategies) of Korean mothers regarding preschoolers' social skills (sharing, controlling negative emotions, and helping others). Participants were 116 mothers in Seoul, Korea. The reasons that mothers provided for the importance of each skill, their causal attributions for the acquisition of those skills, and the socialisation strategies that would be most effective, were targeted. Korean mothers rated controlling negative emotions as less important than sharing and helping others, and were least likely to attribute the importance of social skills to social conventional reasons and provide different ratings and reasons, for the importance of children's skills depending on the sex of their child. Specifically, mothers posit more moral reasons for girls, but more developmental reasons for boys. Also, Korean mothers made more external causal attributions than internal attributions for being good at sharing and helping, whereas emotion regulation was thought to be equally a factor of external and internal reasons. In terms of socialisation strategies, Korean mothers endorsed a higher proportion of modelling than any other strategy for the socialisation of all three social skills, regardless of the sex of the child. In conclusion, Korean mothers' beliefs were related to both traditional and modern Korean ideologies and values in meaningful ways. This study highlights the significance of cultural ideologies regarding children and the family in the study of maternal beliefs regarding child socialisation. (Contains 4 tables.)

We present a high-power conversion efficiency (PCE) on-chip switched-capacitor (SC) DC–DC step-up converter for a fully implantable neural interface operating with less than a few tens µW from energy harvesting. To improve the PCE in such light loads and wide variations of voltage-conversion ratio (VCR), which is a typical scenario for ultra-low-power fully implantable systems depending on energy harvesting, a phase-reduced soft-charging technique has been implemented in a step-up converter, thereby achieving very low VCR-sensitive PCE variation compared with other state-of-the-art works. The proposed DC–DC converter has been fabricated in a standard 180 nm CMOS 1P6M process. It exhibits high PCE (~80%) for wide input and output ranges from 0.5 V to 1.2 V and from 1.2 V to 1.8 V, respectively, with switching frequencies of 0.3–2 MHz, achieving a peak efficiency of 82.6% at 54 µW loads. [ABSTRACT FROM AUTHOR]