The diamond–graphite hybrid thin film with low‐dimensional nanostructure (e.g., nitrogen‐included ultrananocrystalline diamond (N‐UNCD) or the alike), has been employed in many impactful breakthrough ...applications. However, the detailed picture behind the bottom–up evolution of such intriguing carbon nanostructure is far from clarified yet. Here, the authors clarify it, through the concerted efforts of microscopic, physical, and electrochemical analyses for a series of samples synthesized by hot‐filament chemical vapor deposition using methane–hydrogen precursor gas, based on the hydrogen‐dependent surface reconstruction of nanodiamond and on the substrate‐temperature‐dependent variation of the growth species (atomic hydrogen and methyl radical) concentration near substrate. The clarified picture provides insights for a drastic enhancement in the electrochemical activities of the hybrid thin film, concerning the detection of important biomolecule, that is, ascorbic acid, uric acid, and dopamine: their limits of detections are 490, 35, and 25 nm, respectively, which are among the best of the all‐carbon thin film electrodes in the literature. This work also enables a simple and effective way of strongly enhancing AA detection.
The authors clarify the nucleation/growth mechanism of diamond–graphite hybrid thin film with 2D nanostructure (the only successful diamond probe material for neural recording/stimulation), based on nanodiamond surface reconstruction controlled by growth species variation in growth environment. It provides insights for the drastic enhancement of the structure‐optimized thin film performance in simultaneous electrochemical detection of dopamine, ascorbic acid, and uric acid.
Mid-infrared wavelengths are called the molecular fingerprint region because it contains the fundamental vibrational modes inherent to the substances of interest. Since the mid-infrared spectrum can ...provide non-destructive identification and quantitative analysis of unknown substances, miniaturized mid-infrared spectrometers for on-site diagnosis have attained great concern. Filter-array based on-chip spectrometer has been regarded as a promising alternative. In this study, we explore a way of applying a pillar-type plasmonic nanodiscs array, which is advantageous not only for excellent tunability of resonance wavelength but also for 2-dimensional integration through a single layer process, to the multispectral filter array for the on-chip spectrometer. We theoretically and experimentally investigated the optical properties of multi-periodic triangular lattices of metal nanodiscs array that act as stopband filters in the mid-infrared region. Soft-mold reverse nanoimprint lithography with a subsequent lift-off process was employed to fabricate the multispectral filter array and its filter function was successfully extracted using a Fourier transform infrared microscope. With the measured filter function, we tested the feasibility of target spectrum reconstruction using a Tikhonov regularization method for an ill-posed linear problem and evaluated its applicability to the infrared spectroscopic sensor that monitors an oil condition. These results not only verify that the multispectral filter array composed of stopband filters based on the metal nanodiscs array when combined with the spectrum reconstruction technique, has great potential for use to a miniaturized mid-infrared on-chip spectrometer, but also provide effective guidance for the filter design.
A novel nano-plasmonic sensing platform based on vertical conductive bridge was suggested as an alternative geometry for taking full advantages of unique properties of conductive junction while ...substantially alleviating burdens in lithographic process. The effects of various geometrical parameters on the plasmonic properties were systematically investigated. Theoretical simulation on this structure demonstrates that the presence of vertical conductive bridge with smaller diameter sandwiched between two adjacent thin nanodiscs excites a bridged mode very similar to the charge transfer plasmon and exhibits a remarkable enhancement in the extinction efficiency and the sensitivity when the electric field of incident light is parallel to the conductive bridge. Furthermore, for the electric field perpendicular to the bridge, another interesting feature is observed that two magnetic resonance modes are excited symmetrically through open-gaps on both sides of the bridge together with strongly enhanced electric field intensity, which provides a very favorable environment as a surface enhanced Raman scattering substrate for fluid analysis. These results verify a great potential and versatility of our approach for use as a nanoplasmonic sensing platform. In addition, we demonstrated the feasibility of fabrication process of vertical conductive bridge and high tunability in controlling the bridge width.
Interest in the emergence of new masculinity in East Asian mass culture has continuously increased. Research has undertaken explorations of the masculinity of East Asian men, especially new beauty ...standards set by Korean boy bands, also known as K-pop idols, which have researchers on the topic of male beauty and masculinity. Indeed, current trends show that an increasing number of East Asian men are spending longer grooming themselves. Originally from Japanese manga culture, "Bishonen," or pretty boys, a new ideal for romantic partners in East Asia. After Hana Yori Dango (Boys Over Flowers)--one of the most popular shojo mangas in East Asia--was adapted into TV series in Taiwan, Japan, and South Korea, the flower boys' syndrome swept East Asia and reshaped the notion of attractive men and the standard of male beauty.
Ginger (
), the most widely consumed species, is traditionally used as a folk medicine to treat some inflammatory diseases in China and Korea. However, the functional activity of steamed ginger ...extract on gastric ulcers has not been previously explored. The present study aimed to investigate antiulcer activity of steamed ginger extract (GGE03) against ethanol (EtOH)/HCl-induced gastric ulcers in a rat model. GGE03 (100 mg/kg) was orally administered for 14 days to rats before oral intubation of an EtOH/HCl mixture to induce gastric damage. Pretreatment with GGE03 markedly protected the formation of microscopic pathological damage in the gastric mucosa. Further, administration of GGE03 significantly increased mucosal total nitrate/nitrite production in gastric tissues, and elevated total GSH content, catalase activity and superoxide dismutase (SOD) expression as well as decreasing lipid peroxidation and myeloperoxidase (MPO) activity. Underlying protective mechanisms were examined by assessing inflammation-related genes, including nuclear factor-κB (NF-κB), prostaglandin E2 (PGE
), and pro-inflammatory cytokines levels. GGE03 administration significantly reduced the expression of NF-κB and pro-inflammatory cytokines. Our findings suggest that GGE03 possesses antiulcer activity by attenuating oxidative stress and inflammatory responses.
Inspired by information processing in biological systems, sensor-combined edge-computing systems attract attention requesting artificial sensory neurons as essential ingredients. Here, we introduce a ...simple and versatile structure of artificial sensory neurons based on a novel three-terminal Ovonic threshold switch (3T-OTS), which features an electrically controllable threshold voltage (V th). Combined with a sensor driving an output voltage, this 3T-OTS generates spikes with a frequency depending on an external stimulus. As a proof of concept, we have built an artificial retinal ganglion cell (RGC) by combining a 3T-OTS and a photodiode. Furthermore, this artificial RGC is combined with the reservoir-computing technique to perform a classification of chest X-ray images for normal, viral pneumonia, and COVID-19 infections, releasing the recognition accuracy of about 86.5%. These results indicate that the 3T-OTS is highly promising for applications in neuromorphic sensory systems, providing a building block for energy-efficient in-sensor computing devices.
Most South Korean stars and celebrities show glowing flawless skin with a bright tone, which is termed mibaek and constitutes the core imagery of 'K-beauty.' Korean media plays a big part in ...validating this skin beauty norm by producing and mediating an idealised 'televisual skin.' While skin whitening has been interpreted in a colonial or westernised sense, this article defines mibaek as a somatechnics of constructing stardom and explicates it in a Korean media context. Based on observations on star and celebrity image in television dramas, reality TV and K-pop, and in-depth interviews with media and beauty practitioners, this article explains how Korean stars and celebrities employ skin beauty as somatechnics in five ways to: deliver romantic narratives; express a fantasy-like persona; attain extraordinariness; embody trans-Asian sensitivity; and negotiate femininity. This study reveals that mibaek allows stars and celebrities to present their bodies in particular ways, including via fan labour, to be desired by audiences. The study concludes by suggesting more areas for further inquiry on the construction of skin beauty in the Korean star industry.
•SiGe epitaxy thin films were synthesized by an ion beam-assisted solid phase epitaxy process.•The interface oxide was shown to play an important role in hindering epitaxy growth.•The SiGe epitaxy ...CBRAM devices provide forming-free and more reliable operations.
Low dimensional defects such as dislocation in single crystal Si are known to serve as a fast diffusion path of metal ions. Recently, many efforts have been made to employ dislocations in single crystal based oxide and silicon as reliable Ag filaments in CBRAM (Conductive Bridge Resistive Memory). In this study, we report the synthesis of the SiGe epitaxy thin films by an ion beam-assisted solid phase epitaxy process and its application for analog CBRAM memristors. The epitaxial SiGe thin films were produced by implanting Ge ions into a LPCVD a-Si film, followed by post annealing. We found that the interface oxide between a-Si and c-Si hinders facile epitaxy growth of a-Si. Thus, the ion implantation parameters were carefully adjusted to effectively remove the interface oxide and produce the epitaxy thin films of high quality. The low dimensional defects, identified to be a stacking fault by TEM observations, were observed to be densely located near the surface region of the SiGe epitaxy thin film. We fabricated the CBRAM devices by sandwiching the epitaxial Si thin films between an active metal electrode of Ag and a heavily doped Si wafer. We investigated the performances of the CBRAM devices and discuss the effect of the low dimensional defects on the switching behaviors of the devices. We found that the Ge implantation enables forming-free CBRAM operation and also provides reduced variations in set and reset voltages. Furthermore, we performed the feasibility study on the use of the epitaxial Si based CBRAM for artificial synapse for neuromorphic computing.
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