• Proceedings of the KWS Conference
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• 1997.10a
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• pp.77-80
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• 1997

Spot welding has been used in the sheet metal joining processes because of its high productivity and convenience. In this study, predicting methods of fatigue life of spot welded joint have been studied fatigue life of conch-peel spot welded joint was influenced by tail effect. Fatigue life was estimated by stress index parameter considering multiaxial stresses and tail effect. Fatigue tests were conducted with the coach-peel specimens using SPCC.

• Journal of Life Science
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• v.19 no.11
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• pp.1598-1604
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• 2009

In order to determine chemical components of onion flesh and peel, general nutrients, vitamin C, and total flavonoids were measured. Onion peel showed less moisture (14.3%) and no vitamin C compared to onion flesh. Onion peel contained more amounts of total flavonoids compared to onion flesh. In addition, the inhibitory effects of solvent extracts from onion flesh and peel on $H_2O_$-induced oxidative stress and growth of cancer cell lines (AGS human gastric adenocarcinoma and HT-29 human colon cancer cells) were investigated. Acetone with methylene chloride (A+M) and methanol (MeOH) extracts from onion flesh and peel appeared to significantly reduce the levels of intracellular reactive oxygen species (ROS) (p<0.05) and a greater antioxidant effect was observed in onion peel. Among fractions, 85% aq. methanol showed a higher protective activity against oxidative stress in both flesh and peel and there was no effect in the water and hexane fractions. The growth of cancer cells exposed to medium containing extracts and fractions from onion flesh and peel was inhibited dose-dependently. The growth of AGS was inhibited more in both flesh and peel compared to HT-29, and onion peel was more effective than onion flesh. Among fractions, 85% aq. methanol showed the greatest effect on growth inhibition in both flesh and peel. $IC_{50}$ values of 85% aq. methanol fraction from onion flesh and peel on AGS were 0.04 and 0.03 mg/ml, respectively, while those on HT-29 were 0.23 and 0.04 mg/ml. From our results, 85% aq. methanol fraction had an inhibitory effect against oxidative stress and growth of cancer cells, suggesting that it may contain biological active compounds.

• Journal of Life Science
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• v.23 no.12
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• pp.1553-1556
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• 2013

Flavonoids are one of the major components found in the peels of citrus fruits. Present evidence has suggested that polymethoxyflavonoids, including nobiletin and tangeretin isolated from Citrus sunki, have many biological properties, such as anti-inflammatory, anti-oxidant, and anti-obesity capabilities. Here, we investigated the effect of Citrus sunki peel extract and its possible mechanisms on oxidative stress-induced MMP-1 expression, a major marker of skin photoaging. $H_2O_2$ induced MMP-1 expression in a dose- and time-dependent manner. Extract of Citrus sunki peel (1-25 ${\mu}g/ml$) dose-dependently decreased MMP-1 mRNA levels. When $H_2O_2$ was combined with Citrus sunki peel extract, the phosphorylation of ERK was further decreased compared to a single treatment with $H_2O_2$ alone. Moreover, U0216, an MEK inhibitor, markedly prevented the production of MMP-1. These data suggest that Citrus sunki peel extract has demonstrated protective activity against oxidative damage on MMP-1 expression, and ERK MAP kinase may be involved.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.465-470
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• 2001

The adhesively-bonded joints considered in this investigation include single-lap joint and double-lap joint. For an adhesively bonded double-lap joint, end mismatch between the two cuter adherends(upper, lower) can not removed completely although it can be controlled within a manufacturing tolerance. This paper shows that the end mismatch introduces local bending and end mismatch affects the shear and peel stresses in the adhesive. The double-lap joint with an end mismatch is affected of adhesive thickness, material properties of adhesive and adherend etc. Also, we concluded that there are critical value of an end mismatch to provoke the interface fracture.

• Preventive Nutrition and Food Science
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• v.21 no.1
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• pp.14-23
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• 2016

Non-alcoholic fatty liver disease (NAFLD) is caused by fat accumulation and is associated with oxidative stress. In this study, we investigated the potential protective effect of pomegranate (Punica granatum L.) peel extract (PPE) against oxidative stress in the liver of rats with NAFLD. Sprague-Dawley rats were fed a high fat diet (HFD), 20% corn oil, or palm oil for 8 weeks in the presence or absence of PPE. The control group was fed a basal diet. The progression of NAFLD was evaluated histologically and by measuring liver enzymes (alanine transaminase and aspartate transaminase), serum lipids (triglycerides and total cholesterol), and oxidative stress markers. The HFD feeding increased the body weight and caused NAFLD, liver steatosis, hyperlipidemia, oxidative stress, and elevated liver enzymes. Administration of PPE ameliorated the hepatic morphology, reduced body weight, improved liver enzymes, and inhibited lipogenesis. Furthermore, PPE enhanced the cellular redox status in the liver tissue of rats with NAFLD. Our findings suggest that PPE could improve HFD-induced NAFLD via abolishment of hepatic oxidative damage and hyperlipidemia. PPE might be considered as a potential lead material in the treatment of NAFLD and obesity through the modulation of lipid metabolism.

• Journal of the Microelectronics and Packaging Society
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• v.29 no.2
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• pp.59-64
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• 2022

Effects of film stack structure and peeling rate on the peel strength of screen-printed (SP) Ag/polyimide (PI) systems were investigated by a 90° peel test. When PI film was peeled at PI/SP-Ag and PI/SP-Ag/electroplated (EP) Cu structures, the peel strength was nearly constant regardless of the peeling rate. When EP Cu was peeled at EP Cu/SP-Ag/PI structure, the peel strength continuously increased as peeling rate increased. Considering uniaxial tensile test results of EP Cu/SP-Ag film with respect to loading rate, the increase of 90° plastic bending energy and peel strength was attributed to increased flow stress and toughness. On the other hand, viscoelastic PI film showed little variation of flow stress and toughness with respect to loading rate, which was assumed to result in nearly constant 90° plastic bending energy and peel strength.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.4051-4055
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• 2012

Functional foods include antioxidant nutrients which may protect against many human chronic diseases by combating reactive oxygen species (ROS) generation. The purpose of the present study was to investigate the protective effect of pomegranate peel extract (PPE) on azoxymethane (AOM)-induced colon tumors in rats as an in vivo experimental model. Forty Sprague-Dawley rats (4 weeks old) were randomly divided into 4 groups containing 10 rats per group, and were treated with either AOM, PPE, or PPE plus AOM or injected with 0.9% physiological saline solution as a control. At 8 weeks of age, the rats in the AOM and PPE plus AOM groups were injected with 15 mg AOM/kg body weight, once a week for two weeks. After the last AOM injection, the rats were continuously fed ad-libitum their specific diets for another 6 weeks. At the end of the experiment (i.e. at the age of 4 months), all rats were killed and the colon tissues were examined microscopically for lesions suspected of being preneoplastic lesions or tumors as well as for biochemical measurement of oxidative stress indices. The results revealed a lower incidence of aberrant crypt foci in the PPE plus AOM administered group as compared to the AOM group. In addition, PPE blocked the AOM-induced impairment of biochemical indicators of oxidative stress in the examined colonic tissue homogenates. The results suggest that PPE can partially inhibit the development of colonic premalignant lesions in an AOM-induced colorectal carcinogenesis model, by abrogating oxidative stress and improving the redox status of colonic cells.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.6
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• pp.166-173
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• 1998

The evaluation of joint fatigue strength of light weight materials for an electrical vehicle body has been performed through T-peel joint tests with the design parameters such as joint style, adherend type, adherend thickness, adhesive thickness, and various adhesives. Fatigue strength was evaluated through 5-Hz, tension-tension, load controlled test with the zero stress ratio. It was observed that the fatigue strength of the joint increases with the increase of the adherend thickness. With the increase of the adhesive thickness, however, the fatigue strength of the joint increases insignificantly. An aluminum-FRP adherend combination shows much higher fatigue strength than an aluminum-aluminum adherend combination. The results of fatigue tests were found to be consistent with those of static tests.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.208-213
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• 2002

When a thermoset conductive adhesive joints are subjected to the thermal cycles, the thermal stresses are developed around the joints. Most of in-plane, hi-axial components of these residual stresses induces large tensile peel stresses and weakens adhesive joints. Also these stresses vary with thermal cycles, and result in thermal fatigue loading and debonding propagation. In this study, the thermal ratchetting effect in conductive adhesive joints are evaluated by the finite element analysis with the viscoelastic material model. In order to Investigate the relationship between thermal ratchetting and glass transition temperature, the mathematical material model has been developed experimentally by dynamic mechanical analysis. These material models are implemented to the finite element analysis with thermal loading cycles. And the stress profiles around the conductive adhesive joints are calculated. It has been observed that the thermal ratchetting occurs when the maximum temperature of thermal cycles is above the glass transition temperature. The peel and shear stress components increase as the thermal loading time increases. This will contributes to thermal fatigue fracture of the joints.

• Nutrition Research and Practice
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• v.18 no.1
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• pp.33-45
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• 2024

BACKGROUND/OBJECTIVES: Onion, particularly onion peel, is a quercetin-rich food with, anti-inflammatory and immunomodulatory effects. However, the effect of onion peel extract (OPE) in humans is unclear. Thus, the present study aimed to investigate whether OPE improves natural killer (NK) cell activity and cytokine concentration in a randomized double-blind placebo-controlled trial. SUBJECTS/METHODS: Eighty participants aged 19-64 yrs old with a white blood cell count of 4,000-10,000 cells/µL, symptoms of upper respiratory infection at least once within the previous 12 mon, and perceived stress scale (PSS) over 14 were included. Participants were randomly assigned to take either 1,000 mg/day OPE or a placebo for 8 weeks. RESULTS: Compliance were 87.4 ± 8.6% and 86.9 ± 79.0% in OPE and placebo groups. Compared to the placebo, OPE supplementation improved "Hoarseness" (P = 0.038) of the Wisconsin Upper Respiratory Symptom Survey (WURSS)-21 symptom, and stress scores (P = 0.001; 0.021) of PSS. Supplementation of OPE had no significant effect on NK cell activity and concentrations of cytokines such as interleukin (IL)-2, IL-6, IL-12, IL-1β, interferon-γ, and tumor necrosis factor-α. At baseline, the WURSS-21 symptom and PSS score (P = 0.024; 0.026) were higher in the OPE group than the placebo group. Among participants with higher than median WURSS-21 symptom score, OPE supplementation increased NK cell activity (P = 0.038). Supplementation of OPE had no significant effects on safety measurements and adverse events. CONCLUSIONS: The present study suggested that OPE supplementation improves NK cell activity in participants with moderate upper respiratory symptoms without any significant adverse effects.