• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.8
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• pp.34-45
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• 1994

We studied threshold voltages and I-V characteristics. considering short channel effect of the fully depleted thin film n-channel SOI MOSFET. We presented a charge sharing model when the back surface of short channel shows accumulation depletion and inversion state respectively. A degree of charge sharing can be compared according to each of back-surface conditions. Mobility is not assumed as constant and besides bulk mobility both the mobility defined by acoustic phonon scattering and the mobility by surface roughness scattering are taken into consideration. I-V characteristics is then implemented by the mobility including vertical and parallel electric field. kThe validity of the model is proved with the 2-dimensional device simulation (MEDICI) and experimental results. The threshold voltage and charge sharing region controlled by source or drain reduced with increasing back gate voltage. The mobility is dependent upon scattering effect and electric field. so it has a strong influence on I-V characteristics.

• Journal of the Korean Institute of Telematics and Electronics
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• v.23 no.4
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• pp.484-489
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• 1986

A device with variable stepped oxide layer along the edge region of Schottky junction have been designed and fabricated. The effect of this stepped oxide layer in the edge region improves the breakdown voltage as a result of the by increase of the depletion layer width, and decreases the leakage current as compared to the effect of conventional field oxide layer, when the reverse voltage was applied. Experimental results shown that the Schottky diode with the the reverse voltage was applied. Experimenal results show that the Schottky diode with the optimal stepped oxide layer maintains nearly ideal I-V characteristics and excellent breakdown voltage(170V) by reducing the edge effect inherent in metal-semiconductor contacts. The optimal conditions of stepped oxide layer are 1700\ulcornerin thickness and 10\ulcorner in length.

• Herbal Formula Science
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• v.28 no.4
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• pp.327-337
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• 2020

Objective : Citri Unshius Pericarpium is the dried peel of mature fruit of Citrus unshiu Markovich and has been used to treat indigestion, vomiting, and removal of phlegm. This study investigated the hepatoprotective and antioxidant effect of CEE (Ethanol extract of Citri Unshius Pericarpium) in cadmium (CdCl₂)-treated HepG2 cells. Methods : Component analysis of Citri Unshius Pericarpium was analyzed by UPLC with C₁₈ column. Cell viability was determined by MTT assay. The enzyme activity of superoxide dismutase (SOD) and the level of reactive oxygen species (ROS) and reduced glutathione (GSH) were analyzed using commercially available kits. Results : Cadmium caused severe HepG2 cell death. Cadmium also increased ROS production, consistent with depletion of GSH and inhibition of the SOD enzyme. However, CEE treatment reduced cell death and relieved oxidative stress caused by cadmium toxicity. CEE lowered ROS levels and improved depletion of GSH levels. CEE also enhanced the enzymatic activity of SOD. In component analysis, hesperidin was the most abundant of the five marker compounds (Narigenin, Narigin, Narirutin, Hesperidin and Hesperidin), which assumes that hesperidin partially contributed to the antioxidant activity of CEE. Conclusion : These results suggested that CEE could be a potential substance to solve heavy metal-related health problems. In particular, inhibition of oxidative stress by CEE can be a way to treat liver damage caused by cadmium.

• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4291-4296
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• 2011

Gravitational SPLITT fractionation (GSF) provides separation of colloidal particles into two subpopulations in a preparative scale. Conventionally, GSF is carried out in a thin rectangular channel having two inlets and two outlets at the top and bottom of the channel, respectively. And the channel is equipped with two flow-splitters, one between the top and bottom inlets and another between the top and bottom outlets. A large scale splitter-less GSF system had been developed, which was designed to operate in the full feed depletion (FFD) mode. In the FFD mode, there is only one inlet through which the sample is fed, thus preventing the sample dilution. In this study, the effect of the sample-loading (in the unit of g/hr) on the fractionation efficiency (FE, number% of particles in a GSF fraction that have the sizes expected by theory) of the new large scale splitter-less FFD-GSF system was investigated. The system was tested in the sample-loading range of 3.0-12.0 g/hr with polyurethane latex beads (PU) and sea-sediment. It was found that there is an optimum range in the sample-loading for a FFD-GSF separation. It was also found that there is a general tendency of FE decreasing as the concentration of the sample suspension increases.

• Journal of Nutrition and Health
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• v.40 no.4
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• pp.362-370
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• 2007

The study was designed to assess the effect of iron and cereal supplementation on children's iron nutritional status in social welfare institutions. Dietary survey was carried out methods of food weighing and record by interview (n=74). A nutritional intervention study was carried out through supplementing iron supplements and cereal for 4 weeks in 4-12 years old children. Children received daily 40 mg elemental Fe as iron protein succinylate (n=23) and 3.6 mg elemental Fe as 100 g cereal (n=24), respectively. Blood samples were drawn before and after supplementation. Nutrients which children's intake was less than two-thirds of the RDA were vitamin A, vitamin B-1, vitamin B-2, calcium and iron. The mean daily intake of iron was 5.1 mg for male and 4.9 mg for female, and 52.3% for male and 45.4% for female of Korean RDA. The proportion of children with iron depletion assessed by TIBC (> 360 ${\mu}g$/dl) and serum ferritin (< 20 ng/ml) were 56.6% and 58.7%, respectively. The proportion of children with the iron deficient erythropoiesis assessed by serum iron (< 70 ${\mu}g$/dl), Hb (< 12 g/dl), Hct (< 36%) were 76.0%, 58.7%, 64.0%, respectively. After iron supplements treatment, Hb (p<0.001), Hct(p<0.001), serum iron (p<0.001), transferrin saturation (p<0.001) and serum ferritin (p<0.Ol) increase significantly and only TIBC decreased slightly. After cereal supplementation, in anemic children, Hct (p<0.001), serum iron (p<0.001) and transferrin saturation (p<0.001) were significantly increased. The effect of iron supplements and cereal supplementation in children with iron deficient erythropoiesis were more effective to improve the iron nutritional status than children with iron depletion. It was concluded that cereal supplementation program in anemic children was also effective to improve iron nutritional status.

• Molecules and Cells
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• v.39 no.10
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• pp.742-749
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• 2016

The cancer chemo-preventive effects of equol have been demonstrated for a wide variety of experimental tumours. In a previous study, we found that equol inhibited proliferation and induced apoptotic death of human gastric cancer MGC-803 cells. However, the mechanisms underlying equol-mediated apoptosis have not been well understood. In the present study, the dual AO (acridine orange)/EB (ethidium bromide) fluorescent assay, the comet assay, MTS, western blotting and flow cytometric assays were performed to further investigate the pro-apoptotic effect of equol and its associated mechanisms in MGC-803 cells. The results demonstrated that equol induced an apoptotic nuclear morphology revealed by AO/EB staining, the presence of a comet tail, the cleavage of caspase-3 and PARP and the depletion of cIAP1, indicating its pro-apoptotic effect. In addition, equol-induced apoptosis involves the mitochondria-dependent cell-death pathway, evidenced by the depolarization of the mitochondrial membrane potential, the cleavage of caspase-9 and the depletion of Bcl-xL and full-length Bid. Moreover, treating MGC-803 cells with equol induced the sustained activation of extracellular signal-regulated kinase (ERK), and inhibiting ERK by U0126, a MEK/ERK pathway inhibitor, significantly attenuated the equol-induced cell apoptosis. These results suggest that equol induces mitochondria-dependent apoptosis in human gastric cancer MGC-803 cells via the sustained activation of the ERK1/2 pathway. Therefore, equol may be a novel candidate for the chemoprevention and therapy of gastric cancer.

• Journal of the Korean Society of Food Culture
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• v.18 no.6
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• pp.575-583
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• 2003

To evaluate the effect of cereal supplementation on children's iron nutritional status of Korean institutionalized was designed. Dietary survey was carried out methods of food weighting in the breakfast or/and dinner, and record interview in lunch (n=74). A nutritional intervention study was carried out through supplementing cereal for 4 weeks in 24 children of 1 institution from 4 to 12 years. The children received 3.6mg elemental Fe(as 100g cereal) per day. Blood samples were drawn before and after supplementation. Nutrients which children's intake was less than two-thirds of Korean RDA were Vit A, Vit B1, Vit B2, Ca and Fe. The mean daily intakes of iron were 5.1mg for male and 4.9mg for female and 52.3% for male and 45.4% for female of Korean RDA. The proportions of children with iron depletion assessed by TIBC(>360mg/dl) and serum ferritin(<20ng/ml) were 56.6% and 58.7%, respectively. The proportions of children with the iron deficient erythropoiesis assessed by serum iron(<70ml/dl), Hb(<12g/dl), and Hct(<36%) were 76.0%, 58.7%, and 64.0%, respectively. After cereal supplementation, in anemic children, levels of Hct(p<0.001), serum iron(p<0.001) and transferrin saturation(p<0.001) were significantly increased. The effect of cereal supplementation in children with iron deficient erythropoeisis was more effective to improve the iron nutritional status than children with iron depletion. It was concluded that cereal supplementation program in anemic children was also effective to improve iron nutritional status.

• The Korea Journal of Herbology
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• v.28 no.3
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• pp.25-31
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• 2013

Objectives : To develop a natural antioxidant and anti-hemolytic agents, we investigated the effects of ethanol extracts of Carpesii Fructus and Farfarae Flos. Methods : Aerial parts of Carpesii Fructus and Farfarae Flos were extracted with 80% ethanol. Antioxidant activity of Carpesii Fructus or Farfarae Flos extract was evaluated by employing three different assays, i.e., 1,1-diphenyl-2-picryl hydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzthiazoline-6-suphonic acid) diammonium (ABTS) scavenging and reducing power activities. Also, anti-hemolytic activity of Carpesii Fructus or Farfarae Flos extract was determined using [2,2'-azobis (2-methylpropionamidine) dihydrochloride (AAPH)]-induced hemolysis, glutathione (GSH) depletion and malondialdehyde (MDA) formation in normal rat red blood cells (RBC) or plasma. Results : The extracts obtained from Carpesii Fructus and Farfarae Flos dose-dependently increased the scavenging activity on DPPH- or ABTS-induced radicals and the reducing power activities. Carpesii Fructus and Farfarae Flos were similar to the scavenging activity and the reducing power of butylated hydroxy anisole effect at high concentration ($1,000{\mu}g/mL$). RBC oxidative hemolysis and plasma MDA formation induced by AAPH were significantly suppressed by the extracts of Carpesii Fructus and Farfarae Flos in a dose-dependent manner. Also, Carpesii Fructus and Farfarae Flos extracts prevented the depletion of cystosolic antioxidant GSH in RBCs. Carpesii Fructus generally had better than the free radical scavenging activity, the reducing power and anti-hemolytic effects of Farfarae Flos. Conclusions : These results suggest that Carpesii Fructus and Farfarae Flos may have value as the potential antioxidant and anti-hemolytic medicinal plant.

• Journal of Korea Water Resources Association
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• v.39 no.11 s.172
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• pp.935-946
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• 2006

This study proposed a new procedure of sustainable water resources planning to prevent the urban streamflow depletion, based on the Heathcote's study in 1998: (1) to understand the watershed component and processes, (2) to identify and quantify problems within the watershed, (3) to set clear and specific goals, (4) to develop a list of management options, (5) to eliminate infeasible options, (6) to test the effectiveness of remaining feasible options, and (7) to develop the final options. PSR(Presure-State-Response) concept was used for the determination of indicators of PSD(Potential Streamflow Depletion; step 2) and effect equation (step 7) and composite programming for the calculation of PSD. The instreamflow requirement was proposed as clear and specific goal (step 3) and was determined by the larger of the PHABSIM's environmental flow and the drought flow. A continuous rainfall-runoff model is necessary to test the effectiveness of alternatives. It should estimate not only the exact runoff but also the effect of landuse change, reservoir, infiltration facility and so on like SWAT(Soil and Water Assessment Tool). The proposed procedure will be applied on the corresponding paper.

• Journal of the Korean Vacuum Society
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• v.16 no.5
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• pp.359-365
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• 2007

In this paper we present a bottom-gate type of zinc oxide (ZnO) and Gallium (Ga) doped zinc oxide (GZO) based thin film transistors (TFTs) through applying a radio frequency (RF) magnetron sputtering method at room temperature. The gate leakage current can be reduced up to several ph by applying $SiO_2$ thermally grown instead of using new gate oxide materials. The root mean square (RMS) values of the ZnO and GZO film surface were measured as 1.07 nm and 1.65 nm, respectively. Also, the transmittances of the ZnO and GZO film were more than 80% and 75%, respectively, and they were changed as their film thickness. The ZnO and GZO film had a wurtzite structure that was arranged well as a (002) orientation. The ZnO TFT had a threshold voltage of 2.5 V, a field effect mobility of $0.027\;cm^2/(V{\cdot}s)$, a on/off ratio of $10^4$, a gate voltage swing of 17 V/decade and it operated in a enhancement mode. In case of the GZO TFT, it operated in a depletion mode with a threshold voltage of -3.4 V, a field effect mobility of $0.023\;cm^2/(V{\cdot}s)$, a on/off ratio of $2{\times}10^4$ and a gate voltage swing of 3.3 V/decade. We successfully demonstrated that the TFTs with the enhancement and depletion mode type can be fabricated by using pure ZnO and 1wt% Ga-doped ZnO.