10 research outputs found

    Nano-Floating Gate Memory Devices Composed of ZnO Thin-Film Transistors on Flexible Plastics

    Get PDF
    Nano-floating gate memory devices were fabricated on a flexible plastic substrate by a low-temperature fabrication process. The memory characteristics of ZnO-based thin-film transistors with Al nanoparticles embedded in the gate oxides were investigated in this study. Their electron mobility was found to be 0.18 cm2/V·s and their on/off ratio was in the range of 104–105. The threshold voltages of the programmed and erased states were negligibly changed up to 103 cycles. The flexibility, memory properties, and low-temperature fabrication of the nano-floating gate memory devices described herein suggest that they have potential applications for future flexible integrated electronics

    Evaluation of fatty acids in groomed fingerprint by gas chromatographic analysis using various extraction solvents and treatment methods

    Get PDF
    Extremely small amounts of fatty acids detected in latent fingerprints are important for studying fingerprint visualization and age determination through changes in composition over time. However, methods for efficiently extracting or recovering fatty acids from fingerprints have not been extensively studied. If accurate and stable quantitative estimations are established, age estimates will be possible through a better understanding of the fatty acid composition. The extraction solvent and treatment method are essential factors for achieving a reliable analysis of fatty acids. There have been few previous studies that efficiently compared fatty acids. In this study, fatty acids from sebaceous fingerprint residues were quantified with various extraction solvents and treatment methods and were evaluated with gas chromatography flame ionization detection (GC-FID). All data were analyzed using a statistical method.Center for Research and Development of Police science and Technology and Korean National Police Agency (PA-H000001) The Korea government (Ministry of Education) (NRF-2017R1D1A1B03030163) The Korea government (Ministry of Science, ICT and Future Planning) (MSIP) (No. NRF-2018M3C1B7020722) The Ministry of Health & Welfare, Republic of Korea (Grant Number:) (HI14C1277) Ministry of Science, ICT & Future Planning (NRF-2017M3A9E9072939) Seoul National University Hospital Research Fund (Grant 26-2015-0030

    Nano-Floating Gate Memory Devices Composed of ZnO Thin-Film Transistors on Flexible Plastics

    No full text
    <p>Abstract</p> <p>Nano-floating gate memory devices were fabricated on a flexible plastic substrate by a low-temperature fabrication process. The memory characteristics of ZnO-based thin-film transistors with Al nanoparticles embedded in the gate oxides were investigated in this study. Their electron mobility was found to be 0.18 cm<sup>2</sup>/V&#183;s and their on/off ratio was in the range of 10<sup>4</sup>&#8211;10<sup>5</sup>. The threshold voltages of the programmed and erased states were negligibly changed up to 10<sup>3</sup> cycles. The flexibility, memory properties, and low-temperature fabrication of the nano-floating gate memory devices described herein suggest that they have potential applications for future flexible integrated electronics.</p

    Skin-Whitening and Antiwrinkle Proprieties of Maackia amurensis Methanolic Extract Lead Compounds

    No full text
    (1) Background: This study aimed to investigate the feasibility of using Maackia amurensis branch extract as a cosmetic ingredient with skin-whitening and antiwrinkle effects. (2) Methods: The skin-whitening effect of M. amurensis branch extract was confirmed by investigating &alpha;-melanocyte-stimulating hormone (&alpha;-MSH)-induced melanin synthesis and melanogenic protein expression in B16F1 cells. The antiwrinkle effect of M. amurensis branch extract was verified by assessing matrix metalloproteinase (MMP)-1 expression and soluble collagen content in CCD-986sk cells. The major compounds in M. amurensis branch extract were identified through isolation and characterization and confirmed by high-performance liquid chromatography analysis. (3) Results: M. amurensis branch extract significantly inhibited &alpha;-MSH-induced melanin synthesis by 49%, 42%, and 18% at 50, 37.5, and 25 &mu;g/mL concentrations, respectively, compared with the negative control (NC). M. amurensis branch extract also significantly reduced the expression of the microphthalmia-associated transcription factor, tyrosinase-related protein (TRP)-1, TRP-2, and tyrosinase in B16F1 cells. Furthermore, M. amurensis branch extracts decreased ultraviolet A-induced MMP-1 expression and increased soluble collagen synthesis in CCD-986sk cells. In addition, the major compounds present in M. amurensis branch extract were found to be formononetin, genistein, trans-resveratrol, piceatannol, and tectoridin. (4) Conclusions: M. amurensis branch extract has skin-whitening and antiwrinkle properties. Therefore, it can be used as an ingredient in functional cosmetics with skin-whitening and antiwrinkle effects

    Automated Detection of Rice Bakanae Disease via Drone Imagery

    No full text
    This paper proposes a system for the forecasting and automated inspection of rice Bakanae disease (RBD) infection rates via drone imagery. The proposed system synthesizes camera calibrations and area calculations in the optimal data domain to detect infected bunches and classify infected rice culm numbers. Optimal heights and angles for identification were examined via linear discriminant analysis and gradient magnitude by targeting the morphological features of RBD in drone imagery. Camera calibration and area calculation enabled distortion correction and simultaneous calculation of image area using a perspective transform matrix. For infection detection, a two-step configuration was used to recognize the infected culms through deep learning classifiers. The YOLOv3 and RestNETV2 101 models were used for detection of infected bunches and classification of the infected culm numbers, respectively. Accordingly, 3 m drone height and 0° angle to the ground were found to be optimal, yielding an infected bunches detection rate with a mean average precision of 90.49. The classification of number of infected culms in the infected bunch matched with an 80.36% accuracy. The RBD detection system that we propose can be used to minimize confusion and inefficiency during rice field inspection

    MED28 Over-Expression Shortens the Cell Cycle and Induces Genomic Instability

    No full text
    The mammalian mediator complex subunit 28 (MED28) is overexpressed in a variety of cancers and it regulates cell migration/invasion and epithelial-mesenchymal transition. However, transcription factors that increase MED28 expression have not yet been identified. In this study, we performed a luciferase reporter assay to identify and characterize the prospective transcription factors, namely E2F transcription factor 1, nuclear respiratory factor 1, E-26 transforming sequence 1, and CCAAT/enhancer-binding protein &#946;, which increased MED28 expression. In addition, the release from the arrest at the G1&#8722;S or G2&#8722;M phase transition after cell cycle synchronization using thymidine or nocodazole, respectively, showed enhanced MED28 expression at the G1&#8722;S transition and mitosis. Furthermore, the overexpression of MED28 significantly decreased the duration of interphase and mitosis. Conversely, a knockdown of MED28 using si-RNA increased the duration of interphase and mitosis. Of note, the overexpression of MED28 significantly increased micronucleus and nuclear budding in HeLa cells. In addition, flow cytometry and fluorescence microscopy analyses showed that the overexpression of MED28 significantly increased aneuploid cells. Taken together, these results suggest that MED28 expression is increased by oncogenic transcription factors and its overexpression disturbs the cell cycle, which results in genomic instability and aneuploidy

    Manufacturing and Control of a Robotic Device for Time-averaged Simulated Micro and Partial Gravity of a Cell Culture Environment

    No full text
    Gravity is omnipresent for all objects on Earth. However, in an environment of different gravitational stress (e.g., microgravity or partial gravity), cells and organs show different biological responses. So, researchers have attempted to achieve micro- or partial gravity on Earth through various approaches, such as parabolic flight or free fall. However, the duration of such ground experiments is highly limited, making it very difficult to conduct time-consuming tasks, such as cell culture. Thus, a three-dimensional (3D) clinostat is utilized as an alternative for experiments on the International Space Station. It provides time-averaged simulated micro- and partial gravity by using mechanical frames with two rotating actuators. This study proposes novel control algorithms for simulating micro- and partial gravity and validates them by applying it to the control of a manufactured 3D clinostat. First, the novel algorithm for time-averaged simulated microgravity (taSMG) provided a more uniformly distributed gravity field by reducing two poles the gravity-concentrated areas. The taSMG with reduced poles provides isotropic gravitational patterns, from which it is possible to minimize the unnecessary effect due to nonuniformity of the gravity vector direction. Second, the other suggested novel algorithm for time-averaged simulated partial gravity (taSPG) controls the pole sizes asymmetrically to generate the intended size of partial gravity. The suggested algorithms are based on mathematical models rather than totally randomized motions. Therefore, the convergence of gravity values, in the rotating frame over time, can be analytically predicted with improved accuracy compared with previously reported algorithms. The developed 3D clinostat hardware and algorithms will effectively provide well-validated taSMG and taSPG for cell growth experiments in future studies for space medicine
    corecore