Publications by authors named "You Na Lee"

Background: Late-life depression (LLD) is a risk factor for Alzheimer's disease (AD) dementia. Previous morphological studies have often associated LLD with atrophy within the medial temporal lobe (MTL), including the hippocampus. A number of previous studies have demonstrated the changes in several MTL subfields in LLD, such as the perirhinal cortex (PrC), cornu ammonis (CA), dentate gyrus (DG), subiculum and entorhinal cortex (EC), but with inconsistent results, which may be explained by the relatively low image resolution of the 3T scanner used in the previous studies.

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An anode bimetallic catalyst comprising Ni-Pd alloy nanoparticles was loaded on acid-treated multi-walled carbon nanotubes (MWCNTs) for application in a direct urea fuel cell. The bimetallic catalyst and MWCNTs were synthesized by a hydrothermal method at 160°C for 5 h. To reduce the catalyst particle size, alkaline resistance, and facilitate their uniform distribution on the surface of the MWCNTs, phosphorus (P) was added to the Ni-Pd/MWCNT catalyst.

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Various biosensing platforms for real-time monitoring and mapping of chemical signals in neural networks have been developed based on CMOS process technology. Despite their achievements, however, there remains a demand for an advanced method that can offer detailed insights into cellular functions with higher spatiotemporal resolution. Here, we present a pH image sensor that employs a high-density array of 256 × 256 pixels and readout circuitry designed for fast operation.

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Few studies have investigated the gas-sensing properties of graphene oxide/titanium dioxide (GO/TiO₂) composite combined with photocatalytic effect. Room temperature gas-sensing properties of the GO/TiO₂ composite were investigated towards various reducing gases. The composite sensor showed an enhanced gas response and a faster recovery time than a pure GO sensor due to the synergistic effect of the hybridization, such as creation of a hetero-junction at the interface and modulation of charge carrier density.

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We report here a new bio-image sensor for simultaneous detection of spatial and temporal distribution of multi-neurotransmitters. It consists of multiple enzyme-immobilized membranes on a 128 × 128 pixel array with read-out circuit. Apyrase and acetylcholinesterase (AChE), as selective elements, are used to recognize adenosine 5'-triphosphate (ATP) and acetylcholine (ACh), respectively.

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A bio-image sensor using a patterned apyrase-immobilized membrane was developed to visualize the activities of adenosine triphosphate (ATP) and H ion in real-time. An enzymatic membrane patterning technique was suggested to immobilize apyrase on a specific sensing area of a charge coupled device (CCD)-type image sensor. It was able to observe the spatiotemporal information of ATP and H ion.

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