• Journal of the Korean Society of Food Science and Nutrition
• /
• v.33 no.7
• /
• pp.1112-1118
• /
• 2004

This study was carried out to evaluate the free radical scavenging effect and antioxidant effect of Cham-Dang-Gui (Angelica gigas) on cyclophosphamide (CYP) injected rats. Rats were divided into five groups： CON (normal group), ANS (CYP-injected and normal diet group), AND (CYP-injected and normal diet and Cham-Dang-Gui-treated group), ALS (CYP-injected and low iron diet group), and ALD (CYP-injected and low iron diet and Cham-Dang-Gui-treated group). CYP (30 mg/kg) was intraperitoneally injected to rats for early 3 days. Saline or Cham-Dang-Gui was administrated orally for entire experimental period. DPPH radical scavenger activity was measured by DPPH method, it was shown higher in methanol extract (81.5％) than in water extract (66.3％) of Cham-Dang-Gui. We observed the preventive effects of Cham-Dang-Gui on lipid oxidation of liver and protein oxidation of plasma. Hepatic SOD and catalase activities were significantly higher in CYP-injected group (ANS) than CON group, but SOD activity was slightly lowered in Cham-Dang-Gui treated group than CYP-injected group (ANS). These results suggest that extract of Cham-Dang-Gui could be useful for functional materials to reduce the oxidation of lipids and protein induced by free radicals.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.22 no.12
• /
• pp.1028-1032
• /
• 2009

In this study, the influences of silicon-based gas barrier films fabricated by using a facing target sputtering(FTS) system on the gas permeability for flexible displays have been investigated. Under these optimum conditions on the $SiO_x$ film with oxygen concentration($O_2/Ar+O_2$) of 3.3% and the $SiO_xN_y$ film with nitrogen concentration($N_2/Ar+O_2+N_2$) of 30% deposited by the FTS system, it was found that the films were grown about 4 times higher deposition rate than that of the conventional sputtering system and showed high transmittance about 85% in the visible light range. Particularly, the polyethylene naphthalate(PEN) substrates with the $SiO_x$ and/or $SiO_xN_y$ films showed the enhanced properties of decreased water vapor transmission rate (WVTR) over $10^{-1}\;g/m^2{\cdot}day$ compared with the PEN substrate without any gas barrier films, which was due to high packing density in the Si-based films with high plasma density by FTS process and/or the denser chemical structure of Si-N bond in the $SiO_xN_y$ film.

• Nutrition Research and Practice
• /
• v.7 no.3
• /
• pp.178-184
• /
• 2013

This study investigates the impact of exercises, coffee intakes, and physical trainings on fuel utilization in rats. Ninety-six rats were fed a control diet with either water (C) or coffee (CF; 0.12 g freeze-dried instant coffee/100 g body weight/d). Additionally, the animals go through physical training (TC and TCF) or no training (NTC and NTCF) for 4 weeks. For physical training, animals have to exercise on treadmills for 30 minutes (5 d per week, $15^{\circ}$ incline, 0.5-0.8 km/h). At the end of week 4, the animals in each group were subdivided into three exercise groups: before exercise (BE), during exercise (DE), and after exercise (AE). The DE rats exercised on treadmills for 1 hour immediately before being sacrificed. Hemoglobin, hematocrit, glucose, glycogen, protein, triglyceride (TG), and free fatty acid (FFA) levels in the plasma, liver, and skeletal muscle of the rats were compared accordingly. Organ weights were also measured. Coffee-training interaction had a significant impact on heart weight, visceral fat, hemoglobin, hematocrit, liver glycogen in DE and AE, and liver triglyceride in DE and AE. Exercise (meaning exercised on a treadmill for 1 hour immediately before being sacrificed) training interaction was significant in liver glycogen, muscle glycogen in control diet and control diet with coffee, FFA and muscle TG levels at control diet with coffee group. Exercise-coffee interactions significantly influenced the FFA with no training groups. Exercise-coffee-training interaction significantly effects on FFA, Liver TG and Muscle TG. Coffee intakes can increase lipolysis during exercising but coffee consumptions delay the recovery of liver glycogen levels in trained rats after exercising. Coffee intakes can increase lipolysis during exercising but coffee consumptions delay the recovery of liver glycogen levels in trained rats after exercising. Coffee can be an effective ergogenic aid during exercise for physically trained rats.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.34 no.12
• /
• pp.1821-1828
• /
• 2010

Laser shock peening(LSP) is an innovative surface treatment technique, and it has been successfully used to improve the fatigue performance of metallic components. It is widely known, that cracks caused by metal fatigue occur only at the location where the metal is subject to tension, and not at the location where the metal is subjected to compression. Therefore, LSP can be employed to improve fatigue life because it generates a high-magnitude compressive residual stress on the surface and interior of metallic components. In this study, we analyzed the applicability of the LSP method in improving fatigue performance and evaluated the various parameters that influence the compressive residual stress. Further, we analyzed the change in the mechanical properties such as surface dynamic stress and the compressive residual stress on the surface and interior of metallic components.

• Korean Journal of Pharmacognosy
• /
• v.32 no.4 s.127
• /
• pp.327-329
• /
• 2001

Cordyceps militaris (CM) has been used as a tonics in the traditional medicine. To investigate the anti-diabetic principle of CM, activity guided fractionation was conducted. Hot water extract of CM was fractionated into 3 parts: above 100,000(A), $100,000{\sim}20,000(B)$, below 20,000(C) in molecular weight using in membrane filter system. All fractions showed mild hypoglycemic activity in streptozotocin (STZ)-induced diabetic rats by oral administration (300 mg/kg). The fraction C which was most active among them was fractionated again into two parts, C-1 and C-2 by Sephadex LH 20 column chromatography. The fraction C-1 showed hypoglycemic activity but C-2 did not show activity compared with control in STZ mice. In glucose-fed hyperglycemic mice, fraction C, C-1 and C-2 also showed significant glucose lowering activity. Their decreasing rates of plasma glucose level after 1 hours administrations of fraction C, C-1 and C-2 were 24.5%, 29.3% and 22.0%, respectively (Tolbutamide: 48.4%). These results suggested that CM has both insulin like and insulin release promoting activity and could be developed as an antidiabetic agent.

• Korean Journal of Pharmacognosy
• /
• v.12 no.1
• /
• pp.31-43
• /
• 1981

In order to determine the effect of Oryeongsan reputed to have diuretic action since Han Dynasty and possible synergetic action of Dianthi Semen, Polygonum avicularis Herba, Kochiae Fructus and Akebiae Lignum, herbs with similar reputation, when added to the above prescription, their decoction powders were solved into distilled water and injected into rabbits through the ear vein. Upon the treatment, the excretion of sodium, potassium and chloride ion together with urine volume was kinetically determined. At the same time the clearance of plasma creatinine and sodium ion was determined and the following results were obtained. Every experimental group demonstrated diuretic action, though feable, of relatively long duration. The diuretic mechanism in the case of Oryeongsan made up by mixing the seperate extracts of individual components and Oryeongsan(A) plus Dianthi Semen was found to be inhibitory effect of renal tubular reabsorption in contrast to the case of Oryeongsan(A) plus Polygonum avicularis Herba, Kochiae Fructus or Akebiae Lignum in which case the diuretic mechanism was found to be glomerular vascular dilatation. The urinary excretion of potassium ion was increased in the case of Oryeongsan(A) plus Dianthi Semen, Kochiae Fructus of Akebiae Lignum whereas in the other cases no similar change was registered. The diuretic action was most remarkable in the case of Oryeongsan(A) plus Polygonum avicularis Herba followed by Oryeongsan(A) plus Kochiae Fructus, Oryeongsan(A) plus Dianthi Semen, extract mixture of individual component of Oryeongsan, Oryeongsan(A) and Oryeongsan(A) plus Akebiae Lignum decreasing order. The duration of diuretic action was found to be 90 minutes in the case of Oryeongsan and mixture of individual component of Oryeongsan, and 60 minutes in the case of Oryeongsan(A) plus Dianthi Semen, Kochiae Fructus or Akebiae Lignum in contrast to the case of Oryeongsan(A) plus Polygonum avicularis Herba which lasted up to 120 minutes.

• Journal of Sensor Science and Technology
• /
• v.28 no.6
• /
• pp.402-406
• /
• 2019

Recently, semiconducting organic materials have been spotlighted as next-generation electronic materials based on their tunable electrical and optical properties, low-cost process, and flexibility. However, typical organic semiconductor materials are vulnerable to moisture and oxygen. Therefore, an encapsulation layer is essential for application of electronic devices. In this study, SiN_x thin films deposited at process temperatures below 150 ℃ by plasma-enhanced chemical vapor deposition (PECVD) were characterized for application as an encapsulation layer on organic devices. A single structured SiN_x thin film was optimized as an organic light-emitting diode (OLED) encapsulation layer at process temperature of 80 ℃. The optimized SiN_x film exhibited excellent water vapor transmission rate (WVTR) of less than 5 × 10^-5 g/㎡·day and transmittance of over 87.3% on the visible region with thickness of 1 ㎛. Application of the SiN_x thin film on the top-emitting OLED showed that the PECVD process did not degrade the electrical properties of the device, and the OLED with SiN_x exhibited improved operating lifetime

• The Korean Journal of Physiology
• /
• v.29 no.2
• /
• pp.259-267
• /
• 1995

The renin-angiotensin system plays an important role in the regulation of blood pressure and in body fluid homeostasis. There is increasing evidence for generation of endogenous angiotensin II in many organs and for its role in paracrine functions. Studies were designed to investigate whether hemorrhage produces rapid changes in the gene expression of angiotensinogen in peripheral and brain tissues. Wistar rats received saline drinking water for 7 days, were bled at a rate of $3\;ml\;kg^{-1}\;min^{-1}$ for 7 min, and then decapitated 0, 2, 4, 8, or 24 hr after hemorrhage. Hemorrhage produced a produced hypotension with tachycardia at $2{\pm}8\;hr$, but blood pressure and heart rate had not fully recovered to the basal level at 24 hr. Plasma renin concentration was significantly increased at 2, 4, and 8 hr (maximum sixfold increase at 4 hr) and had returned to the basal level at 24 hr. Renal renin content was significantly increased only at 4 hr after hemorrhage. Angiotensinogen mRNA in both the kidney and liver were stimulated at 2 to 8 hrs, but recovered to the basal level at 24 hr. On the other hand, angiotensinogen mRNA levels il the hypothalamus and brainstem were continuously increased from 2 to 24 hrs. The present study demonstrates the presence of angiotensinogen mRNA in both hepatic and extrahepatic tissues, and more importantly, their up-regulation after hemorrhage. These results suggest that the angiotensinogen-generating systems in the liver, kideny and brain are, at least in part, under independent control and play a local physiological role.

• Analytical Science and Technology
• /
• v.16 no.2
• /
• pp.134-142
• /
• 2003

Comparison of a microwave-assisted extraction with sonication extraction was performed for arsenic speciation in fish tissue with chromatographic separation and inductively coupled plasma mass spectrometry detection. The detection limits of arsenicals with ultrasonic nebulizerand cross-flow nebulizer were shown to be similar. The arsenicals investigated were arsenobetaine (AsB), arsenite [As(III)], dimethylarsine acid (DMA), monomethylarsonic acid (MMA), arsenate [As(v)], and phenylarsonic acid (PAA). Quantitative extraction of arsenicals from dogfish muscle, DORM-2, standard reference material of NRCC (National Research Council of Canada) was achieved using 50% (v/v) methanol-water in both extraction methods. Extraction efficiency of arsenobetaine in both methods is greater than 82% with RSDs on replicates of less than 5%. The concentrations of AsB determined in extract of microwave assisted extraction and sonication methods were $14.18{\pm}0.42mg\;kg^{-1}$ and $13.54 {\pm}0.84mg\;kg^{-1}$, respectively. And the concentrations of DMA were $0.45{\pm}0.06mg\;kg^{-1}$ and $0.44{\pm}0.06mg\;kg^{-1}$, respectively.

• Analytical Science and Technology
• /
• v.14 no.1
• /
• pp.34-43
• /
• 2001

The present work is aimed to evaluate the conditions of the hydride generation (HG) for germanium analysis by inductively coupled plasma (ICP)-atomic emission spectrometry (AES). Twelve different kinds of acids were used such as phosphoric, hydrochloric, nitric, sulfuric, perchloric, boric, tartaric, malic, oxalic, tannic, citric, and acetic acid. It was found that phosphoric acid yielded the maximum efficiency of hydride generation. Also, efficient hydride generation was obtined with the buffer solutions containing phosphate ions over a wide range of pH. In addition, in the presence of phosphoric acid the interference caused by metals was suppressed in the hydride generation of germanium. As the concentrations of a reducing agent and a stabilizing increased the hydride generation efficiency and the acid concentration proviaing the maximum intensity were increased. By using an analytical method developed in this study, the contents of germanium in water and rock samples were determined. The detection limit of germanium in the presence of phosphoric acid was $0.03{\mu}g/L$.