118 results on '"Seung-Hee Nam"'
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2. A combination of commercial and traditional food-source-derived enzymatic treatment acts as a potential tool to produce functional yuzu (Citrus junos) powder
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Hana Jeong, Protiva Rani Das, Hayeong Kim, Ae Eun Im, Bo-Bae Lee, Kwang-Yeol Yang, and Seung-Hee Nam
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Enzyme treatment ,Yuzu ,Dietary fiber ,Bitter flavonoid ,Anti-obesity ,Nutrition. Foods and food supply ,TX341-641 ,Food processing and manufacture ,TP368-456 - Abstract
Enzymatic modifications have been applied in citrus to enhance their physicochemical and biological properties and reduce their bitterness. Notwithstanding, research on the combination of enzyme treatment of yuzu is lacking. In this study, yuzu was treated with a combination of isolated cellulase NY203, pectinase UF, and cellulase KN, and this enzymatic treatment was found to increase monosaccharide, naringenin, and hesperetin levels. In contrast, dietary fiber, cellulose, hemicellulose, lignin, and pectin levels were decreased. Moreover, the enzymes disintegrated the inner and outer surface structures and chemical bonding of yuzu, thus improving its solubility rate, water-holding capacity, oil-adsorption capacity, cholesterol-binding capacity, and water-swelling capacity. Furthermore, NY203 + UF + KN combination treatment reduced the bitterness of treated yuzu by 50 % compared with the control. Additionally, NY203 + UF + KN treatment yielded a 28 % decrease in lipid accumulation and two-fold higher lipolytic activity in 3T3L-1 adipocytes. These findings are potentially beneficial to the food/nutraceutical industries regarding functional yuzu powder production.
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- 2023
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3. Nutritional and neuroprotective characterization of 'Tadanishiki' yuzu according to harvesting period or extraction condition
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Bo-Bae Lee, Young-Min Kim, and Seung-Hee Nam
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Plant culture ,SB1-1110 ,Botany ,QK1-989 - Abstract
The present study investigated the phenolic profile, antioxidant activity, and neuroprotective properties of ‘Tadanishiki’ yuzu (Citrus junos, a seedless variety of yuzu) according to harvesting period and extraction condition. High-performance liquid chromatography (HPLC) was used to identify the functional components. To evaluate the neuroprotective properties, scopolamine was used to induce cholinergic dysfunction in human neuroblastoma SH-SY5Y cells pretreated with yuzu extracts. Among the harvesting periods, September provided the optimum fruit weight of yuzu and relatively high amounts of total phenolics (3.67 mg/g DW), flavonoids (10.13 mg/g DW), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity (29.10 μg Vit. C eq.). Of the functional compounds, hesperidin (13.57 mg/100 g DW) and naringin (5.84 mg/100 g DW) were the highest in 5% (w/v) yuzu extracted with 80% ethanol and this extract showed the highest DPPH (289.2 μg Vit. C eq.) scavenging activity. This same extract showed the highest cell viability and lowest cortisol or acetylcholinesterase content in scopolamine-treated SH-SY5Y cells. These results indicate that ‘Tadanishiki’ yuzu harvested in September should be extracted at 5% (w/v) yuzu with 80% EtOH, and this extract might be useful for application as a natural functional additive.
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- 2022
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4. Synthesis of ellagic acid glucoside using glucansucrase from Leuconostoc and characterization of this glucoside as a functional neuroprotective agent
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Hyejin Yu, Hana Jeong, Kwang-Yeol Yang, Jeong-Yong Cho, In Ki Hong, and Seung-Hee Nam
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Ellagic acid ,Glucansucrase ,Leuconostoc mesenteroides ,Transglucosylation ,Brain protective effect ,Biotechnology ,TP248.13-248.65 ,Microbiology ,QR1-502 - Abstract
Abstract Ellagic acid glucoside was synthesized via transglucosylation using sucrose and glucansucrase derived from Leuconostoc mesenteroides B-512 FMCM. After such enzymatic synthesis, the product was purified by 50% ethyl acetate fraction and C18 column chromatography. Modification of ellagic acid glucoside was verified by LC–MS/MS at m/z 485.1 (M + Na)− and m/z 531.1 (M + 3Na)−. The yield of ellagic acid glucoside was 69% (3.47 mM) by response surface methodology using 150 mM sucrose, 300 mU/mL glucansucrase, and 5 mM ellagic acid. The synthesized ellagic acid glucoside showed improved water solubility, up to 58% higher brain nerve cell (SH-SY5Y) protective effect, threefold higher cortisol reducing effect, and fourfold stronger inhibitory effect on acetylcholinesterase (AChE) than ellagic acid. These results indicate that ellagic acid glucoside could be used as a neuroprotective agent.
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- 2021
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5. Development of Fast Protection System with Xilinx ZYNQ SoC for RAON Heavy-Ion Accelerator
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Seung-Hee Nam, Changwook Son, and Jungbae Bahng
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fast protection system ,accelerator control system ,Xilinx ZYNQ ,experimental physics and industrial control system ,RAON heavy-ion accelerator ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The development of the fast protection system (FPS) was driven by the critical need to safeguard internal components of the accelerator from beam damage and minimize operational downtime. During accelerator operation, various faults can occur, posing a significant risk. The FPS acts as a rapid response system, initiating a shutdown signal to a reliable chopper system to prevent beam damage and ensure the operational availability of the accelerator. To meet the stringent shut off time requirements specific to critical faults, the FPS was designed to respond within 50 µs, while the total FPS time, including acquisition, redundancy, and processing, needed to be less than 20 µs. In order to achieve these goals, a customized FPS was developed for the RAON heavy-ion accelerator, utilizing the Xilinx ZYNQ system-on-chip (SoC). The FPS system comprised seven acquisition modules, one mitigation module with an embedded SoC, and employed optical fiber connections for efficient data transmission. This article provides a comprehensive account of the design, development, and testing of the FPS system. Experimental tests were conducted to validate its performance. These tests included verifying the accuracy of cyclic redundancy checks, acquiring interlock signals in short pulses, and measuring the delay time during abnormal signal occurrences. Of particular significance is the measurement of the total signal processing time for a 1 km optical cable in the RAON system, which was determined to be 9.8 µs. This result successfully met the stringent requirement of 20 µs for the FPS time. The ability of the FPS to operate within the desired time frame demonstrates its effectiveness in protecting the accelerator’s components from beam damage and minimizing downtime. Consequently, the FPS ensures the operational availability of the accelerator while maintaining the safety and integrity of its internal systems. By providing a detailed account of the FPS’s design, development, and testing, this article contributes valuable insights into the capabilities of the FPS in real-world accelerator scenarios. The successful implementation of the RAON-optimized FPS with the Xilinx ZYNQ SoC reaffirms its effectiveness as a fast and reliable protection system, thus enhancing the overall operational performance of the accelerator.
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- 2023
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6. Vision-Based Pedestrian’s Crossing Risky Behavior Extraction and Analysis for Intelligent Mobility Safety System
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Byeongjoon Noh, Hansaem Park, Sungju Lee, and Seung-Hee Nam
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crossing behavior analysis ,pedestrian safety ,potential collision risks ,computer vision ,Chemical technology ,TP1-1185 - Abstract
Crosswalks present a major threat to pedestrians, but we lack dense behavioral data to investigate the risks they face. One of the breakthroughs is to analyze potential risky behaviors of the road users (e.g., near-miss collision), which can provide clues to take actions such as deployment of additional safety infrastructures. In order to capture these subtle potential risky situations and behaviors, the use of vision sensors makes it easier to study and analyze potential traffic risks. In this study, we introduce a new approach to obtain the potential risky behaviors of vehicles and pedestrians from CCTV cameras deployed on the roads. This study has three novel contributions: (1) recasting CCTV cameras for surveillance to contribute to the study of the crossing environment; (2) creating one sequential process from partitioning video to extracting their behavioral features; and (3) analyzing the extracted behavioral features and clarifying the interactive moving patterns by the crossing environment. These kinds of data are the foundation for understanding road users’ risky behaviors, and further support decision makers for their efficient decisions in improving and making a safer road environment. We validate the feasibility of this model by applying it to video footage collected from crosswalks in various conditions in Osan City, Republic of Korea.
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- 2022
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7. Antioxidative and Analgesic Effects of Naringin through Selective Inhibition of Transient Receptor Potential Vanilloid Member 1
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Sanung Eom, Bo-Bae Lee, Shinhui Lee, Youngseo Park, Hye Duck Yeom, Tae-Hwan Kim, Seung-Hee Nam, and Junho H. Lee
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naringin ,antioxidant ,TRPV1 ,capsaicine-selective inhibition ,analgesic ,free reactive oxygen species ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Transient receptor potential vanilloid member 1 (TRPV1) is activated in response to capsaicin, protons, temperature, and free reactive oxygen species (ROS) released from inflammatory molecules after exposure to harmful stimuli. The expression level of TRPV1 is elevated in the dorsal root ganglion, and its activation through capsaicin and ROS mediates neuropathic pain in mice. Its expression is high in peripheral and central nervous systems. Although pain is a response evolved for survival, many studies have been conducted to develop analgesics, but no clear results have been reported. Here, we found that naringin selectively inhibited capsaicin-stimulated inward currents in Xenopus oocytes using a two-electrode voltage clamp. The results of this study showed that naringin has an IC50 value of 33.3 μM on TRPV1. The amino acid residues D471 and N628 of TRPV1 were involved in its binding to naringin. Our study bridged the gap between the pain suppression effect of TRPV1 and the preventive effect of naringin on neuropathic pain and oxidation. Naringin had the same characteristics as a model selective antagonist, which is claimed to be ideal for the development of analgesics targeting TRPV1. Thus, this study suggests the applicability of naringin as a novel analgesic candidate through antioxidative and analgesic effects of naringin.
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- 2021
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8. Transglycosylation of gallic acid by using Leuconostoc glucansucrase and its characterization as a functional cosmetic agent
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Seung-Hee Nam, Jeongjin Park, Woojin Jun, Doman Kim, Jin-A Ko, A. M. Abd El-Aty, Jin Young Choi, Do-Ik Kim, and Kwang-Yeol Yang
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Leuconostoc mesenteroides ,Dextransucrase ,Gallic acid ,Glucosylation ,Whitening effect ,Anti-aging effect ,Biotechnology ,TP248.13-248.65 ,Microbiology ,QR1-502 - Abstract
Abstract Gallic acid glycoside was enzymatically synthesized by using dextransucrase and sucrose from gallic acid. After purification by butanol partitioning and preparative HPLC, gallic acid glucoside was detected at m/z 355 (C13, H16, O10, Na)+ by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The yield of gallic acid glucoside was found to be 35.7% (114 mM) by response surface methodology using a reaction mixture of 319 mM gallic acid, 355 mM sucrose, and 930 mU/mL dextransucrase. The gallic acid glucoside obtained showed 31% higher anti-lipid peroxidation and stronger inhibition (Ki = 1.23 mM) against tyrosinase than that shown by gallic acid (Ki = 1.98 mM). In UVB-irradiated human fibroblast cells, gallic acid glucoside lowered matrix metalloproteinase-1 levels and increased the collagen content, which was indicative of a stronger anti-aging effect than that of gallic acid or arbutin. These results indicated that gallic acid glucoside is likely a superior cosmetic ingredient with skin-whitening and anti-aging functions.
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- 2017
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9. Significant Performance and Stability Improvements of Low-Temperature IGZO TFTs by the Formation of In-F Nanoparticles on an SiO2 Buffer Layer
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Ho-young Jeong, Seung-hee Nam, Kwon-shik Park, Soo-young Yoon, Chanju Park, and Jin Jang
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low-temperature coplanar IGZO TFT ,bias stability ,In-F nanoparticles ,Chemistry ,QD1-999 - Abstract
We report the performance improvement of low-temperature coplanar indium–gallium–zinc–oxide (IGZO) thin-film transistors (TFTs) with a maximum process temperature of 230 °C. We treated F plasma on the surface of an SiO2 buffer layer before depositing the IGZO semiconductor by reactive sputtering. The field-effect mobility increases from 3.8 to 9.0 cm2 V−1·s−1, and the threshold voltage shift (ΔVth) under positive-bias temperature stress decreases from 3.2 to 0.2 V by F-plasma exposure. High-resolution transmission electron microscopy and atom probe tomography analysis reveal that indium fluoride (In-F) nanoparticles are formed at the IGZO/buffer layer interface. This increases the density of the IGZO and improves the TFT performance as well as its bias stability. The results can be applied to the manufacturing of low-temperature coplanar oxide TFTs for oxide electronics, including information displays.
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- 2020
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10. Physiochemical, nutritional and functional characterization of 10 different pear cultivars (Pyrus spp.)
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Sun-Hee Yim and Seung-Hee Nam
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Pear cultivars ,nutritional compounds ,functional characterization ,Plant culture ,SB1-1110 ,Botany ,QK1-989 - Abstract
This study was performed to compare the physiochemical properties and nutritional components including sugars, amino acids, and minerals of 10 common pear cultivars cultivated in Korea (four Pyrus spp.). Furthermore, the pear cultivars were characterized for functional properties with respect to phenolic compounds by HPLC/DAD analysis and antioxidant activities using DPPH and ABTS assays. Among the 10 pear cultivars that were tested, Niitaka and Hanareum pears show the best physiochemical properties such as higher sugar/acid ratio and proper firmness. They also showed relatively enriched soluble sugar (12.6 ~ 13.0 g/100g FW), amino acid (4.5 ~ 7.3 g/100 g DW) or mineral contents with high K/Na ratio. For functional properties, Niitaka and Hanareum pears have significantly higher contents of total phenolics (240 mg/100 g DW), arbutin (103 ~ 124 mg/100 g DW), and chlorogenic acid (11 mg/100 g DW) as well as strong antioxidant activities (49 % or 86 %) among cultivars. These results indicate that Niitaka, and Hanareum cultivars, could be best for consumption or favorable processing due to excellent product quality and high concentrations of nutritional and functional compounds.
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- 2016
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11. Antioxidant and whitening activities of five unripe pear cultivars
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Sun-Hee Yim and Seung-Hee Nam
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Unripe pear cultivar ,Arbutin ,antioxidant activity ,whitening activity ,Plant culture ,SB1-1110 ,Botany ,QK1-989 - Abstract
The present study was the first evaluation of the arbutin content, antioxidant activity, and whitening function of the unripe pears of five major Korean pear cultivars. Unripe pears were investigated 30 days after florescence for possible utilization as a whitening ingredient, instead of being thrown away for thinning out. Among the five cultivars tested, Gamcheonbae and Manpungbae had significantly higher total phenolics and arbutin contents, while Niitaka had lower values of both total phenolics and arbutin. For whitening activity related to tyrosinase and cellular melanin formation, Manpungbae also showed the strongest tyrosinase inhibition (4.9 %), and achieved 74% reduction of the cellular melanin compared to non-treated cells. These results indicate that unripe pears, especially the Manpungbae cultivar, could be useful for application as a possible natural whitening additive with high arbutin content and excellent whitening activity.
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- 2015
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12. Multi-purpose low energy beam transport system for light heavy-ion beam accelerator
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Jungbae Bahng, Seong Jun Kim, Jung-Woo Ok, Deuk Soon Ahn, Jang-Hee Yoon, Bong-Hyuk Choi, Seung-Hee Nam, Yona Choi, Jonggi Hong, Mi-Sook Won, and Jin Yong Park
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Nuclear and High Energy Physics ,Instrumentation - Published
- 2023
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13. A Study of the Characteristics of Upcycling Complex Cultural Spaces from a Space Marketing Perspective
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Kyung-Hwa Han, Da-Jeong Jang, Seung-Hee Nam, and Yeon-Sook Hwang
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- 2023
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14. Production of Prunin and Naringenin by Using Naringinase from Aspergillus oryzae NYO-2 and Their Neuroprotective Properties and Debitterization
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Hyeon-Jun Seong, Ae Eun Im, Hayeong Kim, Namhyeon Park, Kwang-Yeol Yang, Doman Kim, and Seung-Hee Nam
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General Chemistry ,General Agricultural and Biological Sciences - Published
- 2023
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15. Fermented Curcuma longa L. Prevents Alcoholic Fatty Liver Disease in Mice by Regulating CYP2E1, SREBP-1c, and PPAR-α
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Moeun Lee, Seung-Hee Nam, Ho-Geun Yoon, Shintae Kim, Yanghee You, Kyung-Chul Choi, Yoo-Hyun Lee, Jeongmin Lee, Jeongjin Park, and Woojin Jun
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Nutrition and Dietetics ,Medicine (miscellaneous) - Published
- 2022
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16. P‐11: Effects of Ar Dilution on N 2 O/SiH 4 PECVD for the Growth of Silicon Oxide Thin Films with Improved Breakdown Voltage Characteristics
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Aram Kim, Bokyoung Lee, Hyeona Kim, Jungho Bang, Seung Hee Nam, Kwon-Shik Park, Jeomjae Kim, and Soo Young Yoon
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Organic Chemistry ,Biochemistry - Published
- 2022
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17. Production of Green Yuzu Peel Tablet and Its Physiochemical or Functional Characterization
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Ae Eun Im, Seung-Hee Nam, Bo-Bae Lee, Youn-sup Cho, and Hae-Sung Cho
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Nutrition and Dietetics ,Chemistry ,Food science ,Food Science ,Characterization (materials science) - Published
- 2021
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18. Synthesis of ellagic acid glucoside using glucansucrase from Leuconostoc and characterization of this glucoside as a functional neuroprotective agent
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In Ki Hong, Hyejin Yu, Kwang-Yeol Yang, Jeong-Yong Cho, Hana Jeong, and Seung-Hee Nam
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0301 basic medicine ,Ellagic acid ,Sucrose ,030106 microbiology ,Biophysics ,Ethyl acetate ,Glucansucrase ,Leuconostoc mesenteroides ,Applied Microbiology and Biotechnology ,Microbiology ,03 medical and health sciences ,chemistry.chemical_compound ,Column chromatography ,Glucoside ,Brain protective effect ,Leuconostoc ,Chromatography ,biology ,biology.organism_classification ,QR1-502 ,030104 developmental biology ,chemistry ,Transglucosylation ,biology.protein ,Original Article ,TP248.13-248.65 ,Biotechnology - Abstract
Ellagic acid glucoside was synthesized via transglucosylation using sucrose and glucansucrase derived from Leuconostoc mesenteroides B-512 FMCM. After such enzymatic synthesis, the product was purified by 50% ethyl acetate fraction and C18 column chromatography. Modification of ellagic acid glucoside was verified by LC–MS/MS at m/z 485.1 (M + Na)− and m/z 531.1 (M + 3Na)−. The yield of ellagic acid glucoside was 69% (3.47 mM) by response surface methodology using 150 mM sucrose, 300 mU/mL glucansucrase, and 5 mM ellagic acid. The synthesized ellagic acid glucoside showed improved water solubility, up to 58% higher brain nerve cell (SH-SY5Y) protective effect, threefold higher cortisol reducing effect, and fourfold stronger inhibitory effect on acetylcholinesterase (AChE) than ellagic acid. These results indicate that ellagic acid glucoside could be used as a neuroprotective agent.
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- 2021
19. Increasing gallic acid contents in green tea extracts using acid hydrolysis
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Seong-Jin Hong, Ha-Nul Lee, Jeong Choi, Hae-Soo Kim, Do Yeon Jeon, Young-Min Kim, Yong-Hee Kwon, Doo-Gyung Moon, and Seung-Hee Nam
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Marketing ,Economics and Econometrics ,General Chemical Engineering ,Beverage industry ,food and beverages ,Hydrochloric acid ,Gallate ,Tannase ,Ingredient ,chemistry.chemical_compound ,chemistry ,Yield (chemistry) ,General Materials Science ,Acid hydrolysis ,Food science ,Gallic acid - Abstract
Gallic acid (GA) is a functional ingredient abundant in Chinese pu-erh tea. The aim of this study was to increase the GA content in green tea extracts using acid hydrolysis. (-)-Epigallocatechin gallate treated with 1 M hydrochloric acid at 110°C for 1 h resulted in a GA yield of 45.6%. However, under these conditions, (-)-epigallocatechin was easily oxidized and rendered undetectable. On applying the same treatment to green tea extracts of Korea-cultivated Chamnok, a native species, and Yabukita, the GA contents increased from 0.17 to 4.87, 0.28 to 5.33 and 0.17 to 4.44 mM, respectively. In Chamnok extracts prepared following harvesting at three different time points, the GA contents increased from 0.17 to 4.48, 0.12 to 5.16 and 0.06 to 5.71 mM. Therefore, it is possible to produce green tea extracts with high GA concentrations using simple acid hydrolysis. This will greatly benefit the production of functional ingredients and will be useful in the beverage industry. Key words: Domestic cultivar, EGCG, EGC, tannase.
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- 2021
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20. Finding the cause of degradation of low-temperature oxide thin-film transistors
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Kwon-Shik Park, Seung-hee Nam, Hyun-Chul Choi, Ho-young Jeong, and Jin Jang
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010302 applied physics ,Materials science ,business.industry ,Transistor ,Oxide ,General Physics and Astronomy ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Amorphous solid ,Threshold voltage ,law.invention ,X-ray reflectivity ,chemistry.chemical_compound ,chemistry ,law ,Sputtering ,Thin-film transistor ,0103 physical sciences ,Degradation (geology) ,Optoelectronics ,0210 nano-technology ,business - Abstract
We report the cause of degradation of low-temperature amorphous indium-gallium-zinc-oxide (a-IGZO) coplanar thin-film transistors (TFTs). As the deposition temperature of the buffer layer was changed from 400 to 200 °C, the field-effect mobility decreased considerably from 15 to 3 cm2 V−1 s−1, the subthreshold swing (SS) increased from ~ 150 to 280 mV dec−1, the threshold voltage shift (ΔVth) under negative bias temperature stress (NBTS) increased from − 0.27 to − 0.33 V, and ΔVth under a positive bias temperature stress (PBTS) increased significantly from 0 to 4.9 V. From the results of high-resolution transmission electron microscopy (HR-TEM) and X-ray reflectivity (XRR), the poor roughness created by sputtering damage of the interface between the gate insulator (GI) and the a-IGZO is the cause of degradation. In addition, through an atomic probe tomography (APT) analysis, the reason low-temperature TFTs have poorer PBTS stability than NBTS is carefully to be due to zinc (Zn)-related defects that create ionized oxygen vacancies. Based on these results, we introduce strategies for realizing low-temperature oxide TFTs using vacuum process. Please confirm if the author names are presented accurately and in the correct sequence as given name, middle name/initial, family name. Also, kindly confirm the details in the metadata are correct. We confirmed all author names. Please check and confirm that the authors and their respective affiliations have been correctly identified and amend if necessary. We checked all authors and their affiliations.
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- 2021
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21. Isolation and characterization of exopolysaccharide-producing Weissella cibaria JNU29 and its application for production of Korean rice cake ‘Sulgidduk’
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Kwang-Yeol Yang, Seung Jin Yoo, Seung Hee Nam, and Su-Hyun Kim
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biology ,Chemistry ,Food science ,Weissella cibaria ,Isolation (microbiology) ,biology.organism_classification ,Food Science - Abstract
Due to the nutritional value of rice cakes, there is renewed interest in this traditional Korean food, and thus various efforts have been made to improve its storage stability. In this study, lactic acid bacteria that produce exopolysaccharides (EPS) were isolated and their physiochemical properties were analyzed. The bacteria were used to produce ‘Sulgidduk’ (a Korean rice cake) with improved storage stability. Among the 107 strains isolated from traditional fermented foods, only five strains were confirmed to produce EPS in MRS media with 10% sucrose. Two of these strains were identified as members of the genus Weissella and three were identified as the Bacillus genus via sequence analysis of 16S rDNA. Among the five strains, the strain Weissella cibaria JNU29 was selected for application to ‘Sulgidduk’, since it is food applicable, viable in artificial gastric and bile juices, and produces the highest content of EPS (16.72 g/L). TLC and HPLC analysis showed that the EPS produced by W. cibaria JNU29 strain was a homopolysaccharide composed of only glucose. A culture solution of the W. cibaria JNU29 strain was mixed with milled rice flour to prepare ‘Sulgidduk’. After incubation for 48 h, the ‘Sulgidduk’ showed lower hardness values than that of the control without the culture solution, and the lactic acid bacteria survived to a level of 7 log CFU/g. Thus, the W. cibaria JNU29 strain, which produces EPS, can be applied for the production of ‘Sulgidduk’, as it delays retrogradation and prevents mold-induced decay to improve shelf life.
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- 2020
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22. Fermented
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Moeun, Lee, Seung-Hee, Nam, Ho-Geun, Yoon, Shintae, Kim, Yanghee, You, Kyung-Chul, Choi, Yoo-Hyun, Lee, Jeongmin, Lee, Jeongjin, Park, and Woojin, Jun
- Subjects
Male ,Mice, Inbred C57BL ,Mice ,Curcuma ,Ethanol ,Liver ,Non-alcoholic Fatty Liver Disease ,Animals ,Cytochrome P-450 CYP2E1 ,Female ,PPAR alpha ,Sterol Regulatory Element Binding Protein 1 ,Fatty Liver, Alcoholic - Abstract
We examined the efficacy of fermented
- Published
- 2022
23. P‐3: LTPS Device and Panel Fabrication Using Excimer Laser Dehydrogenation and Crystallization
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Jin Sung Kim, Soo Young Yoon, Aram Kim, Bok-young Lee, Seung Hee Nam, Jeom-Jae Kim, Mijin Jeong, Kwon-Shik Park, Deuk Ho Yeon, and Bang Jung-Ho
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Materials science ,Fabrication ,Excimer laser ,business.industry ,law ,medicine.medical_treatment ,medicine ,Optoelectronics ,Dehydrogenation ,Crystallization ,business ,law.invention - Published
- 2021
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24. Oligosaccharide production from preserved yuzu juice using Lactobacillus sakei NY 518 and its prebiotic function
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Sae Hyun JEON, Duk-Hyun KIM, Shakti Chandra MONDAL, Kwang-Yeol YANG, Hana JEONG, Bo-Bae LEE, and Seung-Hee NAM
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preserved yuzu ,antibacterial activity ,Nutrition. Foods and food supply ,Lactobacillus sakei ,food and beverages ,T1-995 ,physiochemical properties ,TX341-641 ,Technology (General) ,Food Science ,Biotechnology ,Oligosaccharide - Abstract
This study focused on the physiochemical characteristics of the oligosaccharide produced in preserved yuzu by NY 518 and its functions based on the intestinal health through antimicrobial activities. NY 518 was identified as Lactobacillus sakei. The oligosaccharide produced by L. sakei NY 518 was gluco-oligosaccharide. The oligosaccharide from preserved yuzu (OY) was found to have lower degree of polymerization than the oligosaccharide from sucrose (OS) owing to the presence of tri- to nona-saccharides. These oligosaccharides had lower pH and increased acidity, soluble solids, and viscosity than their substrates. OY had 67% α-glucosidase inhibition activity of OS and higher antibacterial effects on food-poisoning bacteria than OS. These results indicate that the oligosaccharide produced by L. sakei NY 518 in sugar-preserved foods exhibits beneficial functions (antidiabetic and antibacterial activities) and could be a good substitute for sugar.
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- 2022
25. Physiochemical properties and neuroprotective function of Korean major yuzu varieties
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Bo-Bae LEE, Young-Min KIM, Su-Min PYEON, Hyeon-Ju JEONG, Youn-Sup CHO, and Seung-Hee NAM
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variety ,physicochemical property ,neuroprotection ,yuzu ,anti-inflammation ,Food Science ,Biotechnology - Abstract
Three major yuzu varieties, Native, Namhae, and Tadanishiki in Korea were investigated on physiochemical properties and functional characterizations with respect to neuroprotective function (SH-SY5Y cells) or anti-inflammatory (Raw 264.7 cells). Among the three cultivars tested, Namhae had significantly higher fruit weight and total dietary fibers, while Tadanishiki had higher values of both total flavonoid and antioxidant activity. As functional compounds, Tadanishiki contained a 133% of hesperidin and 164% of naringin, compared to those of Native or Namhae. In comparison to other yuzu, Tadanishiki showed the higher cell viability, lower AChE content, lower protein levels of Bcl-2 /Bax, Caspase 3, and PARP at scopolamine-treated SH-SY5Y nerve cell. Tadanishiki and Namhae were effective for anti-inflammation by decreasing of NO production in LPS-induced Raw 264.7 cells. These results indicate that Tadanishiki yuzu, could be useful for application as a possible natural functional additive with high hesperidin content and excellent neuroprotective and anti-inflammation effects.
- Published
- 2022
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26. A review of encapsulation of carotenoids using spray drying and freeze drying
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Jong-Bang Eun, Seung-Hee Nam, Protiva Rani Das, and Ahmed Maruf
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chemistry.chemical_classification ,Degradation kinetics ,food and beverages ,General Medicine ,Carotenoids ,Wall material ,Antioxidants ,Industrial and Manufacturing Engineering ,Encapsulation (networking) ,Bioavailability ,Freeze-drying ,Freeze Drying ,Functional food ,chemistry ,Fruit ,Spray drying ,Food science ,Desiccation ,Carotenoid ,Food Science - Abstract
Carotenoids are potent antioxidants, but they are highly unstable and susceptible during processing and storage. Encapsulation technologies protect against degradation and are capable of releasing individual or combination of bioactive substances during processing as well as development of various functional food products. Moreover, encapsulating agents can be used to increase the stability of carotenoids and form a barrier between the core and wall materials. Suitable encapsulating agents, temperature, and drying methods are the most important factors for the encapsulation process. In this report, we reviewed the current status of encapsulation of carotenoids from different fruits, vegetables, spices, seaweeds, microorganisms, and synthetic sources using various types of encapsulating agents through spray drying and freeze drying. We also focused on the degradation kinetics and various factors that affect the stability and bioavailability of encapsulated carotenoids during their processing and storage.
- Published
- 2019
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27. Physiochemical properties, dietary fibers, and functional characterization of three yuzu cultivars at five harvesting times
- Author
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Jong-Bang Eun, Hye-Sung Cho, Fatima Rameeza, Youn-Sup Cho, Bo-Bae Lee, Hana Jeong, and Seung-Hee Nam
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0106 biological sciences ,chemistry.chemical_classification ,food.ingredient ,Sucrose ,Pectin ,Flavonoid ,Free sugar ,food and beverages ,Fructose ,04 agricultural and veterinary sciences ,040401 food science ,01 natural sciences ,Applied Microbiology and Biotechnology ,Article ,chemistry.chemical_compound ,Hesperidin ,0404 agricultural biotechnology ,food ,chemistry ,010608 biotechnology ,Cultivar ,Food science ,Naringin ,Food Science ,Biotechnology - Abstract
This research focused on physiochemical and nutritional properties and functional characterization of three cultivars of yuzu—Native, Tadanishiki yuzu, and Namhae1—during different seasons. According to the cultivar and harvest time, yuzu cultivars were analyzed for free sugar, dietary fiber, hesperidin, naringin, and flavonoid content as well as antioxidant and antihypertensive activity. During November, Namhae1 exhibited the highest fruit weight, °Brix/acidity ratio, and total dietary fiber content. Tadanishiki contained the highest fructose and sucrose levels, pectin and cellulose contents, and soluble dietary fiber. Tadanishiki also had the highest hesperidin content in October, while the naringin content and antioxidant activity were the greatest in November. Antihypertensive activity was also the strongest for Tadanishiki, which was picked in October and November. These results indicated that Tadanishiki in October or November was the best for consumption or favorable processing because of its excellent product quality and high levels of nutritional and functional compounds.
- Published
- 2020
28. Aqueous green tea infusion extracted by ultra-sonication method, but not by conventional method, facilitates GLUT4 membrane translocation in adipocytes which potently ameliorates high-fat diet-induced obesity
- Author
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Chang-Min Lee, Seung-Hee Nam, Jong-Bang Eun, Protiva Rani Das, Min-Jung Park, Young-Min Kim, and Dong-Il Kim
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030309 nutrition & dietetics ,Sonication ,Flavonoid ,Biophysics ,Chromosomal translocation ,Green tea extract ,Diet, High-Fat ,03 medical and health sciences ,chemistry.chemical_compound ,Mice ,0404 agricultural biotechnology ,Adipocyte ,Adipocytes ,Animals ,Food science ,Obesity ,Pharmacology ,chemistry.chemical_classification ,0303 health sciences ,biology ,Tea ,Chemistry ,Plant Extracts ,Extraction (chemistry) ,04 agricultural and veterinary sciences ,Cell Biology ,040401 food science ,Polyphenol ,biology.protein ,GLUT4 ,Food Science - Abstract
Green tea contains bioactive compounds, such as polyphenols, responsible for its health-promoting effects, including antiobesity and antidiabetic effects. We previously reported that ultra-sonication extraction (UE) could efficiently increase the extraction yield of green tea compounds. In the present study, we found that the extract obtained using UE contained higher phenolic and flavonoid contents than that obtained using the conventional method. We therefore considered the extract as a bioactive metabolite-rich functional green tea extract (BMF-GTE), and tested its glucose-lowering effect by generating an adipocyte cell line stably expressing 7myc-GLUT4-GFP. We found that BMF-GTE treatment increased GLUT4 translocation to the plasma membrane. Moreover, BMF-GTE administration attenuated weight gain in mice fed a high-fat diet (HFD). Importantly, HFD-induced glucose tolerance was ameliorated in the mice receiving BMF-GTE. Therefore, we conclude that BMF-GTE worked against obesity and diabetes, at least partially, by enhancing GLUT4 translocation in adipocytes. PRACTICAL APPLICATIONS: As green tea is one of the most consumed beverages worldwide, its health effects have been widely tested. In our previous studies, we found that ultra-sonication extraction (UE) has the potential to increase the aqueous extraction yield of green tea compounds compared to conventional extraction techniques. In this study, we examined the biological effect of bioactive metabolite-rich functional green tea extract (BMF-GTE) obtained using UE; we observed that administering BMF-GTE lowered the body weight and increased insulin sensitivity in mice fed a high-fat diet, potentially by facilitating the membrane translocation of GLUT4 in adipocytes. Therefore, this study suggests that the extract obtained with UE had antiobesity and antidiabetic properties, indicative of a potential application of UE in maximizing the beneficial effects of green tea on human health.
- Published
- 2020
29. Review on Predictors of Weight Loss in Obesity Treatment
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Seo-Young Kim, Young-Woo Lim, Seung-Hee Nam, and Young-Bae Park
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03 medical and health sciences ,medicine.medical_specialty ,0302 clinical medicine ,Weight loss ,business.industry ,Internal medicine ,medicine ,030209 endocrinology & metabolism ,030212 general & internal medicine ,medicine.symptom ,medicine.disease ,business ,Obesity - Published
- 2018
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30. Silymarin Contents and Liver Protection Effects of Six Domestic Cultivated Thistles
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Bang-Hee Lee, Seung-Hee Nam, and Yeon-Ji Kim
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Biology - Published
- 2018
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31. Increasing gallic acid contents in green tea extracts using acid hydrolysis
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Hae-Soo, Kim, primary, Do, Yeon Jeon, additional, Ha-Nul, Lee, additional, Seong-Jin, Hong, additional, Seung-Hee, Nam, additional, Jeong, Choi, additional, Yong-Hee, Kwon, additional, Doo-Gyung, Moon, additional, and Young-Min, Kim, additional
- Published
- 2021
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32. Synthesis and Functional Characterization of Caffeic Acid Glucoside Using Leuconostoc mesenteroides Dextransucrase
- Author
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Thi Thanh Hanh Nguyen, Jin-A Ko, Young-Jung Wee, Seung-Hee Nam, Young-Min Kim, Marie K. Walsh, Doman Kim, Ji Young Kim, Kwang-Yeol Yang, and Songhee Han
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0106 biological sciences ,0301 basic medicine ,Sucrose ,Leuconostoc mesenteroides ,01 natural sciences ,Chemical synthesis ,Cell Line ,Dextransucrase ,03 medical and health sciences ,chemistry.chemical_compound ,Caffeic Acids ,Bacterial Proteins ,Glucosides ,Glucoside ,010608 biotechnology ,Caffeic acid ,Humans ,Cell Proliferation ,chemistry.chemical_classification ,Chromatography ,biology ,Chemistry ,Butanol ,food and beverages ,General Chemistry ,biology.organism_classification ,030104 developmental biology ,Enzyme ,Biochemistry ,Glucosyltransferases ,Biocatalysis ,Lipid Peroxidation ,General Agricultural and Biological Sciences - Abstract
Caffeic acid was modified via transglucosylation using sucrose and dextransucrase from Leuconostoc mesenteroides B-512FMCM. Following enzymatic modification, a caffeic acid glucoside was isolated by butanol separation, silica gel chromatography, and preparative HPLC. The synthesized caffeic acid glucoside had a molecular mass-to-charge ratio of 365 m/z, and its structure was identified as caffeic acid-3-O-α-d-glucopyranoside. The production of this caffeic acid-3-O-α-d-glucopyranoside at a concentration of 153 mM was optimized using 325 mM caffeic acid, 355 mM sucrose, and 650 mU mL–1 dextransucrase in the synthesis reaction. In comparison with the caffeic acid, the caffeic acid-3-O-α-d-glucopyranoside displayed 3-fold higher water solubility, 1.66-fold higher antilipid peroxidation effect, 15% stronger inhibition of colon cancer cell growth, and 11.5-fold higher browning resistance. These results indicate that this caffeic acid-3-O-α-d-glucopyranoside may be a suitable functional component of food and ph...
- Published
- 2017
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33. Sensory characterisation of a high-protein beverage
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Ashwini Wagh, Seung-Hee Nam, Marie K. Walsh, and Silvana Martini
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Light transmission ,animal structures ,Chemistry ,Process Chemistry and Technology ,Flavour ,Bioengineering ,Sensory system ,04 agricultural and veterinary sciences ,040401 food science ,Sensory analysis ,Protein content ,Mouthfeel ,0404 agricultural biotechnology ,Food science ,Food Science - Abstract
This study investigated the use of sonication to increase the light transmission of protein solutions. Sonicating a five per cent whey/soy blend at pH 4 resulted in a threefold higher light transmission. Sensory analysis showed that panellists preferred the transparency of the sonicated beverage, whereas the smell and flavour of the control beverage were preferred. Overall appearance, colour and mouthfeel were not different. Panellists who preferred the control liked its creamy thickness, while those who preferred the sonicated liked the transparency. Data show that panellists who want a high protein content in their drinks are not looking for clear beverages.
- Published
- 2016
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34. Synthesis and characterization of glucosyl stevioside using Leuconostoc dextransucrase
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Doman Kim, Young Bae Ryu, Seung-Hee Nam, Jin-A Ko, Woo Song Lee, Ji-Young Park, YongJung Wee, and Young-Min Kim
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Carbonated Beverages ,medicine.disease_cause ,01 natural sciences ,Analytical Chemistry ,Dextransucrase ,0404 agricultural biotechnology ,Glucosides ,Leuconostoc citreum ,medicine ,Humans ,Leuconostoc ,Food science ,Stevioside ,biology ,Chemistry ,010401 analytical chemistry ,Taste Perception ,04 agricultural and veterinary sciences ,General Medicine ,Sweetness ,biology.organism_classification ,040401 food science ,0104 chemical sciences ,Glucosyltransferases ,Sweetening Agents ,Food Additives ,Diterpenes, Kaurane ,Rebaudioside A ,Food Science - Abstract
Glucosyl stevioside was synthesized via transglucosylation by dextransucrase from Leuconostoc citreum KM20 (LcDexT), forming α-d-glucosyl stevioside. A production yield of 94% was reached after 5days of LcDexT reaction at 30°C. Glucosyl stevioside induced a 2-fold improved quality of taste and sweetness, compared to stevioside. After 15days of storage at 25°C, 98% of glucosyl stevioside in an aqueous solution was present in a soluble form, compared to only 11% for stevioside or rebaudioside A. Furthermore, glucosyl stevioside exhibited a similar or improved stability in commercially available soft drinks, when compared to stevioside and rebaudioside A. These results suggest that glucosyl stevioside could serve as a highly pure and stable sweetener in soft drinks.
- Published
- 2016
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35. Optimization of Soluble Rutin using Stevioside as a Natural Solubilizer
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Jin-A Ko, Seung-Hee Nam, and Young-Min Kim
- Subjects
Rutin ,chemistry.chemical_compound ,Chromatography ,Solubilization ,Chemistry ,General Earth and Planetary Sciences ,Stevioside ,General Environmental Science - Published
- 2016
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- View/download PDF
36. GPS time server development for the RAON superconducting radio-frequency test facility
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Hyojae Jang, MiJeong Park, Sang-Il Lee, Changwook Son, Seung Hee Nam, Hyungjoo Son, and Myung Ook Hyun
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010302 applied physics ,Test facility ,Computer science ,business.industry ,RF power amplifier ,Superconducting radio frequency ,Electrical engineering ,General Physics and Astronomy ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Clock synchronization ,Proton (rocket family) ,0103 physical sciences ,Network Time Protocol ,Global Positioning System ,0210 nano-technology ,business ,Control logic - Abstract
An ion accelerator, RAON, is going to be built in Daejeon, Korea, by the Rare Isotope Science Project (RISP) team in the Institute of Basic Science (IBS). In this accelerator, various ions, such as uranium, proton, carbon and calcium, will be accelerated and fed to researchers for experiments. To produce the ion beams and to satisfy the requirements, many devices such as accelerating structures, RF power supplies and ion sources will be installed and controlled according to the predefined control logic. For correct control of such devices, time and clock synchronization is essential. A time synchronization test bed is planned for the RAON superconducting radio-frequency (SRF) test facility, and a flexible, low-cost gps-based time server was developed for that purpose. In this paper, detailed information on the developed GPS server and the test results will be described.
- Published
- 2016
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37. Changes in the physicochemical quality, functional properties, and actinidin content of kiwifruit (Actinidia chinensis) during postharvest storage
- Author
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Seung-Hee Nam
- Subjects
0301 basic medicine ,03 medical and health sciences ,Horticulture ,030109 nutrition & dietetics ,0404 agricultural biotechnology ,Actinidia chinensis ,biology ,Chemistry ,Postharvest ,04 agricultural and veterinary sciences ,biology.organism_classification ,040401 food science ,Food Science - Abstract
Kiwifruit (Actinidia chinensis, Hayward) was stored at 25℃ for 0~30 days and investigated to find out the optimum storage time to obtain the best physical and functional properties for consumers’ preference. Kiwifruits was stored at different time period (0, 5, 10, 15, 20, and 30 days) for investigating their physiochemical quality, nutritional components, and functional characteristics. Kiwifruits stored for 20~30 days showed the best physiochemical quality such as higher total acidity and proper firmness. They were also more enriched with dietary fibers, free sugar, and organic acid, although no significant changes were observed in crude protein, crude fat, and moisture content. For functional properties, kiwifruits stored for 20 days showed significantly higher contents of total phenolics, flavonoids, and actinidin. In addition, it showed stronger antioxidant activity, whitening effect, and proteolytic activity when compared with other samples. SDS-PAGE analysis showed the presence of actinidin enzyme in kiwifruits. These results indicated that the kiwifruits stored for 15~20 days possessed excellent quality and high concentrations of nutritional and functional compounds, which could be best for both fresh consumption and product processing
- Published
- 2016
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38. Glucosyl Rubusosides by Dextransucrases Improve the Quality of Taste and Sweetness
- Author
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Ji-Young Park, Jin-A Ko, Cha Young Kim, Young-Min Kim, Seung-Hee Nam, Woo Song Lee, Young Bae Ryu, and Joong Su Kim
- Subjects
0301 basic medicine ,Glycosylation ,Leuconostoc lactis ,medicine.disease_cause ,Applied Microbiology and Biotechnology ,Dextransucrase ,03 medical and health sciences ,Residue (chemistry) ,Glucosyltransferases ,Bacterial Proteins ,Glucosides ,Leuconostoc citreum ,medicine ,Humans ,Moiety ,Leuconostoc ,Food science ,biology ,General Medicine ,Sweetness ,biology.organism_classification ,Flavoring Agents ,030104 developmental biology ,Taste ,Biocatalysis ,Diterpenes, Kaurane ,Biotechnology - Abstract
Glucosyl rubusosides were synthesized by two dextransucrases. LcDexT was obtained from Leuconosotoc citreum, that LlDexT was obtained from Leuconostoc lactis. LcDexT and LlDexT regioselectively transferred a glucosyl residue to the 13-O-glucosyl moiety of rubusoside with high yield of 59-66% as analyzed by TLC and HPLC. Evaluation of the sweetness of these glucosyl rubusosides showed that their quality of taste, in particular, was superior to that of rubusoside. These results indicate that transglucosylation at the 13-O-glucosyl moiety of rubusoside by different regioselective dextransucrases can be applicable for increasing its sweetness and quality of taste.
- Published
- 2016
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39. Changes in total phenolic and flavonoid content and antioxidative activities during production of juice concentrate from Asian pears (Pyrus pyrifolia Nakai)
- Author
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Sun-Hee Yim, Gui-Hun Jiang, Hyun Jung Gwak, Jong-Bang Eun, Young-Min Kim, and Seung-Hee Nam
- Subjects
chemistry.chemical_classification ,Antioxidant ,DPPH ,medicine.medical_treatment ,010401 analytical chemistry ,Flavonoid ,food and beverages ,Pasteurization ,04 agricultural and veterinary sciences ,040401 food science ,01 natural sciences ,Applied Microbiology and Biotechnology ,0104 chemical sciences ,law.invention ,chemistry.chemical_compound ,0404 agricultural biotechnology ,chemistry ,law ,medicine ,Press cake ,Cultivar ,Food science ,Pear juice ,Food Science ,Biotechnology - Abstract
The total phenolic and flavonoid content and antioxidative activities during production of pear juice concentrate (PJC) from two cultivars, Hwasan and Niitaka, were investigated. The main processing steps in PJC production are washing, pressing, pasteurization, clarification, filtration, evaporation, and packaging. Total phenolic and flavonoid content of end-product PJC from Niitaka decreased by 53.11 and 46.47%, respectively, while those from Hwasan decreased by 55.46 and 36.09%, respectively, compared to the phenolic and flavonoid content of original fresh fruit. DPPH radical-scavenging activities, reducing power and nitrate radical-scavenging activities showed a similar tendency as total phenolic and flavonoid content; that is, they decreased in juice concentrate made from both cultivars. Also, antioxidant activities of press cake waste (skin and seeds) from Niitaka and Hwasan pears were higher than fresh pears. In conclusion, antioxidant levels were significantly affected during processing of PJC, especially during the pressing step in which press cake waste retains the seeds and skin.
- Published
- 2016
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40. Functional characterization of purified pear protease and its proteolytic activities with casein and myofibrillar proteins
- Author
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Seung-Hee Nam, Marie K. Walsh, Young-Min Kim, Sun-Hee Yim, and Jong-Bang Eun
- Subjects
0106 biological sciences ,Proteases ,business.product_category ,medicine.medical_treatment ,01 natural sciences ,Applied Microbiology and Biotechnology ,Article ,Meat tenderizer ,0404 agricultural biotechnology ,010608 biotechnology ,Casein ,medicine ,Enzyme kinetics ,chemistry.chemical_classification ,PEAR ,Protease ,Chemistry ,04 agricultural and veterinary sciences ,040401 food science ,body regions ,Enzyme ,Biochemistry ,Dextrin ,business ,Food Science ,Biotechnology - Abstract
This study was performed to characterize pear protease proteolytic activity and investigate the use of pear protease as a meat tenderizer. Pear protease was purified and stabilized by 5% dextrin during lyophilization (dry) or concentration (liquid). Pear protease was further characterized with respect to pH, thermodynamics, and enzyme kinetics. Pear protease was stable at a pH range of 5-8 with an optimum pH of 6.5. From Arrhenius plots, liquid protease showed higher temperature dependency (23.49 kJ/mol) than dry protease (18.62 kJ/mol) due to its higher activation energy. The kcat/Km, catalytic efficiency of enzyme, was similar with 2.9 and 2.7 µM/min with dry and liquid proteases. Pear protease was evaluated for its proteolytic activities with casein and beef myofibrillar proteins by individually and combination with fig and kiwifruit proteases. These result indicated that pear and kiwifruit proteases could be complementary to be a desirable product for meat tenderization.
- Published
- 2016
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41. Enzymatic browning inhibition and antioxidant activity of pear juice from a new cultivar of asian pear (Pyrus pyrifolia Nakai cv. Sinhwa) with different concentrations of ascorbic acid
- Author
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Jong-Bang Eun, Sun-Hee Yim, Seung-Hee Nam, Young-Min Kim, and Gui-Hun Jiang
- Subjects
0301 basic medicine ,PEAR ,030109 nutrition & dietetics ,Antioxidant ,DPPH ,medicine.medical_treatment ,04 agricultural and veterinary sciences ,Ascorbic acid ,040401 food science ,Applied Microbiology and Biotechnology ,Polyphenol oxidase ,03 medical and health sciences ,chemistry.chemical_compound ,0404 agricultural biotechnology ,chemistry ,Botany ,medicine ,Browning ,Cultivar ,Food science ,Nitrite ,Food Science ,Biotechnology - Abstract
Different ascorbic acid (AA) concentrations of 0.16, 0.20, and 0.24% (w/v) were added to pear juice from the new cultivar Pyrus pyrifolia Nakai cv. "Sinhwa". Enzymatic browning reduction and antioxidant activity were analyzed after 24 h at 37°C. Juices with 0.20% added AA showed the highest inhibition of 78.8% of polyphenol oxidase (PPO) activity. L* values of juices a with 0.20 and 0.24% added AA decreased more slowly than controls lacking AA addition and juice with 0.16% added AA after storage for 24 h. Browning indices of juices with added AA were lower than for controls. However, indices increased after storage for 24 h. The DPPH radical-scavenging activity, reducing power, and nitrite scavenging activity of all juices with added AA were higher than for controls and decreased after storage for 24 h. Addition of 0.20% AA to pear juice from the new "Sinhwa" cultivar showed the highest browning activity reduction.
- Published
- 2016
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42. Significant Performance and Stability Improvements of Low-Temperature IGZO TFTs by the Formation of In-F Nanoparticles on an SiO2 Buffer Layer
- Author
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Chanju Park, Jin Jang, Seung-hee Nam, Ho-Young Jeong, Soo Young Yoon, and Kwon-Shik Park
- Subjects
Materials science ,General Chemical Engineering ,Oxide ,chemistry.chemical_element ,02 engineering and technology ,Atom probe ,01 natural sciences ,Article ,law.invention ,lcsh:Chemistry ,low-temperature coplanar IGZO TFT ,chemistry.chemical_compound ,Sputtering ,law ,0103 physical sciences ,General Materials Science ,010302 applied physics ,bias stability ,business.industry ,021001 nanoscience & nanotechnology ,Threshold voltage ,Semiconductor ,lcsh:QD1-999 ,chemistry ,Thin-film transistor ,In-F nanoparticles ,Optoelectronics ,0210 nano-technology ,business ,Layer (electronics) ,Indium - Abstract
We report the performance improvement of low-temperature coplanar indium&ndash, gallium&ndash, zinc&ndash, oxide (IGZO) thin-film transistors (TFTs) with a maximum process temperature of 230 °, C. We treated F plasma on the surface of an SiO2 buffer layer before depositing the IGZO semiconductor by reactive sputtering. The field-effect mobility increases from 3.8 to 9.0 cm2 V&minus, 1·, s&minus, 1, and the threshold voltage shift (&Delta, Vth) under positive-bias temperature stress decreases from 3.2 to 0.2 V by F-plasma exposure. High-resolution transmission electron microscopy and atom probe tomography analysis reveal that indium fluoride (In-F) nanoparticles are formed at the IGZO/buffer layer interface. This increases the density of the IGZO and improves the TFT performance as well as its bias stability. The results can be applied to the manufacturing of low-temperature coplanar oxide TFTs for oxide electronics, including information displays.
- Published
- 2020
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- View/download PDF
43. Comparison of four purification methods to purify cysteine protease from Asian pear fruit (Pyrus pyrifolia)
- Author
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Marie K. Walsh, Seung-Hee Nam, and Kwang-Yeol Yang
- Subjects
0106 biological sciences ,Proteases ,medicine.medical_treatment ,Ion chromatography ,Bioengineering ,01 natural sciences ,Applied Microbiology and Biotechnology ,chemistry.chemical_compound ,0404 agricultural biotechnology ,010608 biotechnology ,medicine ,Ethanol precipitation ,PEAR ,Chromatography ,Protease ,biology ,04 agricultural and veterinary sciences ,040401 food science ,Cysteine protease ,Enzyme assay ,DEAE-Sepharose ,chemistry ,Biochemistry ,biology.protein ,Agronomy and Crop Science ,Food Science ,Biotechnology - Abstract
Pear fruit is one of the most popular fruits, extensively exploited for its protease activity commercially in the food, cosmetic, and pharmacological industries. The aim of this study was to compare four different purification methods for protease purification from an Asian pear cultivar. Pear proteases were purified by ethanol precipitation, two phase partitioning, or ion exchange chromatography (DEAE Sepharose alone or followed by Mono Q). Purified proteases from each method were further evaluated for purification efficiency by SDS-PAGE analysis and enzyme activity with succinlyated casein substrate. All methods produced two protease bands with molecular weights of 36 kDa and 38 kDa. Among the methods, 15% PEG 1000–20% MgSO4 system and DEAE followed by Mono Q chromatography showed efficient separation of protease with high recovery of enzymatic activity (91–98%). DEAE followed by Mono Q chromatography achieved the highest purification fold (15). These result suggested that a two phase partitioning technique is effective as a single purification step for pear protease.
- Published
- 2016
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- View/download PDF
44. Identification and Functional Characterization of Cysteine Protease from Nine Pear Cultivars (Pyrus pyrifolia)
- Author
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Seung-Hee Nam, Kwang-Yeol Yang, Su-Hyun Kim, and Marie K. Walsh
- Subjects
0106 biological sciences ,Gel electrophoresis ,chemistry.chemical_classification ,Proteases ,PEAR ,Protease ,biology ,medicine.medical_treatment ,Flesh ,010401 analytical chemistry ,food and beverages ,01 natural sciences ,Cysteine protease ,Enzyme assay ,0104 chemical sciences ,body regions ,Enzyme ,Biochemistry ,chemistry ,010608 biotechnology ,medicine ,biology.protein ,Food Science - Abstract
This study was performed to compare the total protein and protease content among the whole fruit, flesh, and peel of nine different pear cultivars. Pear proteases were functionally characterized with respect to three enzyme assays. Proteases from pears were further identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, in gel activity staining, and matrix assisted laser desorption/ionization-time of flight mass spectrometry analysis. Flesh from Whasan, Nikita, and Hanareum cultivars contained relatively more total protein and protease and showed high enzyme activities, while Chuwhang contained the lowest amount of protein and protease activity. Protease content and enzyme activities found in the pear flesh or whole fruits were two to six times higher than those in the pear peel. Pear cultivars contained one or two protease bands with molecular weights of 36 kDa and/or 38k Da. The larger band was further identified as a cysteine proteinase with 70% homology to the pear cysteine protease f...
- Published
- 2015
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- View/download PDF
45. Korean Agricultural Workforce Problems and Alternative Measures
- Author
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Seung-hee Nam and Sang-jin Ma
- Subjects
Successor cardinal ,Economic growth ,Agriculture ,business.industry ,Order (exchange) ,Workforce ,Rural area ,business ,Productivity ,Capital formation - Abstract
As the share of agriculture in Korean economy has been decreasing since the 1970s, the Korean agricultural workforce has also declined and agricultural workers in their twenties and thirties have become scarce. Recent Korean agricultural labor productivity is stagnant in growth. Since the 1980s, Korea has been trying to secure young generation in the agriculture sector and rural areas by launching new programs such as Farm Successor Fostering Program (1981), Korea National Agricultural College (1997), and Special Agricultural Program in Agricultural Schools (2006). While each program has its own outcomes, the greying of Korean farmers is likely to continue because of less favorable public perceptions of agriculture, farm youth decrease, old farm retirement and entry, and agricultural school graduates’ scarce entry into farming. In order to solve these problems, this study suggested the following measures: activating education about agriculture; fostering selected agricultural high schools; strengthening the role of agricultural colleges in fostering agricultural workforce; linking retiring farmers and new farmers through farm corporations; launching intermediate organizations in charge of regional agricultural workforce; and supporting capital formation of young farmers.
- Published
- 2015
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- View/download PDF
46. 81-2: Innovative Mask Reduction Process for High Resolution TFT LCDs using Organic Dielectrics
- Author
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Kwon-Shik Park, Min-Joo Kim, Yong-Il Kim, Seung-hee Nam, In-Byeong Kang, Taewhan Kim, Hee-Young Kwack, Kim Nam-Yong, Sanghyuk Won, and Eungyong Kim
- Subjects
Materials science ,business.industry ,Process (computing) ,High resolution ,Organic layer ,Nanotechnology ,Hardware_PERFORMANCEANDRELIABILITY ,Dielectric ,Reduction (complexity) ,Thin-film transistor ,Etching (microfabrication) ,Hardware_INTEGRATEDCIRCUITS ,Optoelectronics ,business ,Layer (electronics) - Abstract
We propose new mask reduction process for high resolution TFT-LCD using organic dielectrics (eg. PAC). After the Vcom layer is patterned, we use the Vcom layer as a mask for etching the organic layer underneath. Finally, we reduced mask processes so that AH-IPS display with organic dielectrics could be made by 5 mask process.
- Published
- 2016
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- View/download PDF
47. Enzymatic synthesis of chlorogenic acid glucoside using dextransucrase and its physical and functional properties
- Author
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Young-Min Kim, Jin-Ho Choi, Woojin Jun, Doman Kim, Songhee Han, Marie K. Walsh, Thi Thanh Hanh Nguyen, Jin-A Ko, Seung-Hee Nam, Kwang-Yeol Yang, Jon-Bang Eun, Jeong Choi, Young-Jung Wee, and Elsevier
- Subjects
0106 biological sciences ,0301 basic medicine ,Sucrose ,Glycosylation ,Antioxidant ,medicine.medical_treatment ,chlorogenic acid ,dextransucrase ,Leuconostoc mesenteroides ,Antineoplastic Agents ,Bioengineering ,01 natural sciences ,Applied Microbiology and Biotechnology ,Biochemistry ,Antioxidants ,Dextransucrase ,Lipid peroxidation ,03 medical and health sciences ,chemistry.chemical_compound ,Bacterial Proteins ,Glucosides ,Chlorogenic acid ,Glucoside ,010608 biotechnology ,Browning ,medicine ,Humans ,Cell Proliferation ,Nutrition ,Chromatography ,biology ,biology.organism_classification ,030104 developmental biology ,Solubility ,chemistry ,Glucosyltransferases ,Polyphenol ,Colonic Neoplasms ,Lipid Peroxidation ,Chlorogenic Acid ,HT29 Cells ,Leuconostoc ,Biotechnology - Abstract
Chlorogenic acid, a major polyphenol in edible plants, possesses strong antioxidant activity, anti-lipid peroxidation and anticancer effects. It used for industrial applications; however, this is limited by its instability to heat or light. In this study, we, for the first time synthesized chlorogenic acid glucoside (CHG) via transglycosylation using dextransucrase from Leuconostoc mesenteroides and sucrose. CHG was purified and its structure determined by nuclear magnetic resonance and matrix-associated laser desorption ionization–time-of-flight mass spectroscopy. The production yield of CHG was 44.0% or 141 mM, as determined by response surface methodology. CHG possessed a 65% increase in water solubility and a 2-fold browning resistance and it displayed stronger inhibition of lipid peroxidation and of colon cancer cell growth by MTT assay, compared to chlorogenic acid. Therefore, this study may expand the industrial applications of chlorogenic acid as water-soluble or browning resistant compound (CHG) through enzymatic glycosylation.
- Published
- 2017
48. Network Structure Modification‐Enabled Hybrid Polymer Dielectric Film with Zirconia for the Stretchable Transistor Applications
- Author
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Seung Hee Nam, Hyeon Kim, Kwon-Shik Park, Ui Jin Chung, Jae Kyeong Jeong, Daesik Kim, Jae Seok Hur, Jeong Oh Kim, Byeongmoon Lee, Yongtaek Hong, and Jae Min Jung
- Subjects
Materials science ,Polymer dielectric ,business.industry ,Transistor ,Network structure ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,law.invention ,Biomaterials ,law ,Electrochemistry ,Optoelectronics ,Cubic zirconia ,business - Published
- 2020
- Full Text
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49. Comparison of the Quality of Hot Pepper(Capsicum annuum L.) Grown under Organic and Conventional Conditions
- Author
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Jin-Woo Lee, Sun-Kyung Lee, Jeong-Hwa Kang, Bong-Yun Oh, Seung-Hee Nam, Kyung-Ju Jung, You-Seok Lee, and Jae-Hak Moon
- Subjects
Capsicum annuum ,Horticulture ,Pepper ,Biology - Published
- 2014
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50. Highly Sensitive Non-Classical Strain Gauge Using Organic Heptazole Thin-Film Transistor Circuit on a Flexible Substrate
- Author
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Sung Wook Min, Seung Hee Nam, Eun Young Park, Seongil Im, Young Tack Lee, and Pyo Jin Jeon
- Subjects
Materials science ,business.industry ,Transistor ,Bending ,Condensed Matter Physics ,Flexible electronics ,Electronic, Optical and Magnetic Materials ,law.invention ,Biomaterials ,Pentacene ,chemistry.chemical_compound ,Strain engineering ,chemistry ,law ,Thin-film transistor ,Electrochemistry ,Optoelectronics ,business ,Strain gauge ,Voltage - Abstract
A non-classical organic strain gauge as a voltage signal sensor is reported, using an inverter-type thin-film transistor (TFT) circuit, which is able to sensitively measure a large quantity of elastic strain (up to ≈2.48%), which approaches an almost folding state. Novel heptazole-based organic TFTs are chosen to be incorporated in this gauge circuit; organic solid heptazole has small domain size in general. While large crystal domain-pentacene TFTs seldom show sufficient current variation upon mechanical bending for tensile strain, these heptazole TFTs demonstrate a significant variation for the same strain condition as applied to pentacene devices. In addition, the pentacene channel does not recover to its original electric state after bending but heptazole channels are very elastic and reversible, even after going through serious bending. More interesting is that the heptazole TFTs show only a little variation of signal current under horizontal direction strain, while they make a significant amount of current decrease under vertical direction strain. Utilizing the anisotropic response to the tensile bending strain, an ultrasensitive voltage output strain gauge composed of a horizontally and vertically oriented TFT couple is demonstrated.
- Published
- 2014
- Full Text
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