Woo Young Choi

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We have demonstrated a 70-nm n-channel tunneling field-effect transistor (TFET) which has a subthreshold swing (SS) of 52.8 mV/dec at room temperature. It is the first experimental result that shows a sub-60-mV/dec SS in the silicon-based TFETs. Based on simulation results, the gate oxide and silicon-on-insulator layer thicknesses were scaled down to 2 and(More)
Combined eye-head movements are routinely used to orient the visual axis (gaze) rapidly in space. The gaze control system can be modeled using a feedback system in which an internally created instantaneous gaze position error signal equivalent to the distance between the target and the current gaze position is used to drive brainstem eye and head motor(More)
Tight junctions (TJs) are critical structures for the maintenance of cellular polarity, acting as paracellular permeability barriers and playing an essential role in regulation of the diffusion of fluid, electrolytes and macromolecules through the paracellular pathway. Matrix metalloproteinases (MMPs) have been implicated as possible mediators of(More)
BACKGROUND The whistle deformity is one of the common sequelae of secondary cleft lip deformities. Santos reported using a crossed-denuded flap for primary cleft lip repair to prevent a vermilion notching. The authors modified this technique to correct the whistle deformity, calling their version the cross-muscle flap. METHODS From May 2005 to January(More)
Since the first case of Ebola virus disease (EVD) in Guinea was reported in March 2014 by World Health Organization (WHO), the outbreak has continued through the year and the total number of 19,065 patients was reported as the confirmed or suspected in the EVD-affected countries. Among the cases, 7,388 patients were reported death by 19 December. Currently,(More)
Sanguinarine is a benzophenanthridine alkaloid, derived from the root of Sanguinaria canadensis and other poppy Fumaria species, which is known to have antimicrobial, antiinflammatory and antioxidant properties. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is known to induce apoptosis in cancer cells but spare most normal cells. However,(More)
UNLABELLED Ethnopharmacological relevance Nardostachys chinensis has been used in folk medicine to treat melasma and lentigines in Korea. We investigated the inhibitory activities of Nardostachys chinensis in melanogenesis and its related signaling pathway. MATERIALS AND METHODS Bioassay-guided fractionation of Nardostachys chinensis using solvent(More)
Sulforaphane, an isothiocyanate found in cruciferous vegetables, has been shown to possess growth-inhibiting and apoptosis-inducing activities in cancer cell lines in vitro. In order to further explore the critical events leading to apoptosis in sulforaphane-treated U937 human leukemia cells, the following effects of sulforaphane on components of the(More)
A prominent hypothesis in motor control is that endpoint errors are minimized because motor commands are updated in real time via internal feedback loops. We investigated in monkey whether orienting saccadic gaze shifts made in the dark with coordinated eye-head movements are controlled by feedback. We recorded from superior colliculus fixation neurons(More)