• Transactions on Electrical and Electronic Materials
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• v.11 no.3
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• pp.106-111
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• 2010

The convergence of significantly different and disparate technologies such as spintronics, carbon nano tube field effect transistors, photon and bio-responsive molecular switches, memristor and memristive systems and metamaterials, coupled with energy scavenging sources are gaining a renewed focus in the quest for new products. This paper will provide an insight into an anticipated technological revolution and will highlight a futuristic Roadmap to capture opportunities that are brought about as the results of formulation of new circuit components basically driven by emergence of nanoscale materials as part of System on System integration. Challenges as the result of new lumped components such as memristor, metamaterial-based lumped components and the like that will challenge the designers' comfort zone will also be discussed.

• Journal of Advanced Marine Engineering and Technology
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• v.13 no.3
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• pp.26-36
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• 1989

Recently digital governor system is commonly adapted for the speed control of the marine diesel engine because of too much fluctuation of rpm resulted by the low speed, long stroke, high efficiency and a small number of cylinder of it, and versatile studies on the development of digital governor system are progressed. On this subject the new control method in which the fuel is controlled by feedforwarding the change of load as well as the feedback of angular velocity in case of disregarding the engine dead time and influence of scavenging air was proposed by the authors, and found the method has shown quite a good control performance in comparision to the conventional control method by the simulation using a digital computer for various load change. In this paper the speed control system of a diesel engine is simulated in case of regarding the engine dead time by the proposed method, and also confirm a good control performance of it under even more realistically simulated environment.

• Korean Journal of Environmental Agriculture
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• v.12 no.3
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• pp.264-280
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• 1993

The environmental pollutions were a serious problem in Korea recently. So many researcher have studied the effect of environmental pollution on plants and agro-ecosystem, but the basic mechanisms of environmental stresses were various. One of the important mechanisms was oxidative stress caused by active toxic oxygen. The toxic oxygen was generated by several stresses, abnormal temperature, many xenobiotics, air pollutants, water stress, fugal toxin, etc. In the species of toxic oxygen which is primary inducer of oxidative stresses, superoxide, hydrogen peroxide, hydroxyl radical and singlet oxygen were representative species. The scavenging systems were divided into two groups. One was nonenzymatic system and the other enzymatic system. Antioxidants such as glutathione, ascorbic acid, and carotenoid, have the primary function in defense mechanisms. Enzymatic system divided into two groups; First, direct interaction with toxic oxygen(eg. superoxide dismutase). Second, participation in redox reaction to maintain the active antioxidant levels(eg. glutathione reductase, ascorbate peroxidase, etc.).

• Journal of Mushroom
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• v.15 no.4
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• pp.206-209
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• 2017

In this study, the morphology and antioxidant content of shiitake mushrooms (Lentinula edodes) cultivated in smart farms and general farms have been compared. With regard to morphology, mushrooms produced in the smart farm system exhibited a slightly thicker and wider pileus and thicker and longer stipe than those in the general farm system. The stipe in the mushrooms from moderate-sized farms was harder, because the low relative humidity of cultivation rooms could induce mushroom tissue to harden. With regard to the antioxidant content, the free radical scavenging activity was evaluated by the DPPH assay. Among the various treatments, hot water extracts of freeze-dried shiitake produced from smart farms exhibited the highest DPPH value of 37.8%. In contrast, the lowest activity of 12.2% was observed in a 70% fermented alcohol extract of shiitake that was dried by hot air. The polyphenol content was higher in hot water extracts than in 70% fermented alcohol extracts. Additionally, the polyphenol content was higher in the freeze-dried samples than in hot-air dried ones. The smart-farm system was preferred over the general cropping system for cultivating shiitake mushrooms, because the antioxidant activity and polyphenol content of mushrooms from the smart-farm system was better; the functionality of this system was more improved than that of the general cropping system, and it enables mushrooms to be cultivated more efficiently. The antioxidant content is represented as the $mean{\pm}SD$ of three replicates. Different letters indicate significant differences among samples, i.e., p<0.05.

• Korean Journal of Food Science and Technology
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• v.49 no.6
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• pp.693-698
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• 2017

Turmeric is a yellow food-coloring spice containing curcuminoids, curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcumin (BMC), which have several physiological effects. In the present study, the effect of microwave irradiation on the chemical properties, antioxidant activity, and cytotoxicity of turmeric were investigated. Degradation of turmeric pigments was accelerated upon increase in irradiation time or intensity at 405 nm. Residual levels of curcumin, DMC, and BMC after 5 minutes of irradiation at 700 W were 11.3, 34.4, and 71.2%, respectively. Scavenging activities of turmeric pigment against 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-azobis (2-amidinopropane) dihydrochloride (AAPH) peroxyl radical and nitrite were enhanced significantly after microwave radiation. However, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity remained unaffected. Cytotoxic activity of turmeric was significantly reduced, and hydrogen peroxide generated from turmeric increased after microwave irradiation. The results obtained indicate that microwave irradiation affects chemical stability and bioactivity of turmeric pigment. Hence, these effects should be considered when processing foods containing turmeric pigments.

• Nutrition Research and Practice
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• v.10 no.4
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• pp.371-376
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• 2016

BACKGROUND/OBJECTIVES: Chronic ultraviolet (UV) exposure-induced reactive oxygen species (ROS) are commonly involved in the pathogenesis of skin damage by activating the metalloproteinases (MMP) that break down type I collagen. Adenophora remotiflora (AR) is a perennial wild plant that inhabits Korea, China, and Japan. The present study investigated the protective effects of AR against UVB-induced photo-damage in keratinocytes. MATERIALS/METHODS: An in vitro cell-free system was used to examine the scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical and nitric oxide (NO). The effect of AR on ROS formation, antioxidant enzymes, elastase, MMP-1 level, and mRNA expression of MMP-1 were determined in UVB-irradiated human keratinocyte HaCaT cells. RESULTS: AR demonstrated strong DPPH free radical and NO scavenging activity in a cell-free system exhibiting $IC_{50}$ values of 1.88 mg/mL and 6.77 mg/mL, respectively. AR pretreatment dose-dependently attenuated the production of UVB-induced intracellular ROS, and antioxidant enzymes (catalase and superoxide dismutase) were enhanced in HaCaT cells. Furthermore, pretreatment of AR prevented UVB-induced elastase and collagen degradation by inhibiting the MMP-1 protein level and mRNA expression. Accordingly, AR treatment elevated collagen content in UVB-irradiated HaCaT cells. CONCLUSION: The present study provides the first evidence of AR inhibiting UVB-induced ROS production and induction of MMP-1 as a result of augmentation of antioxidative activity in HaCaT human keratinocytes. These results suggest that AR might act as an effective inhibitor of UVB-modulated signaling pathways and might serve as a photo-protective agent.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.2
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• pp.457-463
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• 2009

This study aimed to evaluate the anti-asthmatic effects of Seonpye-tang (SPT) using OVA-induced asthmatic mice model. Scavenging activity of SPT on DPPH free radical and SOD-like activity of SPT were measured at final concentration 62.5, 125, 250, 500 (${\mu}g/m{\ell}$), RBL-2H3 cells were treated with DNP IgE for 24hr, and treated with SPT (1, 10, 100 ${\mu}g/m{\ell}$) for 1hr, followed by treatment with DNP-HSA for 1hr at $37^{\circ}C$. The level of IL-4 and TNF-${\alpha}$ were measured by ELISA. Asthmatic mice model was conducted by repeated challenge of OVA using C57BL/6 mice. Each group was treated with distilled water, SPT (400 mg/kg and 200 mg/kg) extract or cyclosporin A (10 mg/kg) for the later 8 weeks. Immune cells subpopulation, eotaxin, IL-5 and TNF-${\alpha}$ in BALF were analyzed. SPT dose-dependently increased Scavenging activity on DPPH free radical and SOD-like activity. SPT significantly ameliorated the increase of total cells number and eosinophil including of immune cell subpopulation of $CD3^+/CD69^+$, $CCR3^+$, $B220^+/CD22^+$, $B220^+/CD45^+$ and $B220^+/IgE^+$ cells in BALF comparing to control group. Eotaxin and IL-5 level in BALF were significantly decreased by SPT. These results strongly suggest that SPT would be a effective candidate for herbal-originated anti-asthmatic drug. However, this drug should be further studied for characterization of the accurate action and underlying mechanisms using variant disease model in the future.

• Journal of Oriental Neuropsychiatry
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• v.17 no.1
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• pp.1-16
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• 2006

Objective: An water extract of the Hwang-Ryun-Chung-Sim-Um (HRC) was assessed to determine the mechanisms of its antioxidant activity. In addition, the HRC was examined in vitro for the inhibitory effect on the acetylcholinesterse (AChE). Methods: The HRC exhibited a concentration-treatment; scavenging ${\alpha},{\alpha}-diphenyl-{\beta}-picrylhydrazyl$ (DPPH) radical, linoleic acid oxidation in a thiocyanate assay system, hydroxyl radical-induced DNA nicking. We investigated mRNA levels such as catalase activity, superoxide-dismutase and glutathione peroxidase. The water extract of HRC showed inhibitory effect on AChE activity. Result: The HRC extract showed dose-dependent free radical scavenging activity, including DPPH radicals and hydroxyl radicals, using different system. The HRC was also found to be effective in protecting plasmid DNA against the strand breakage induced by Hydroxyl radicals in Fenton's reaction mixture. Futhermore, catalase mRNA expression levels increased, but SOD1 and MnSOD was not expressed. HRC in a various concentration-dependent decreased AChE mRNA levels and inhibitory effect showed AChE. Conclusion: According to the above results, it is supposed that HRC is applicable to the Dementia-type of Alzheimer clinically.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.6
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• pp.767-777
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• 2014

Characterizing local chicken types and their mostly rural production systems is prerequisite for designing and implementing development and conservation programs. This study evaluated the management practices of small-scale chicken keepers and the phenotypic and production traits of their chickens in Oman, where conservation programs for local livestock breeds have currently started. Free-range scavenging was the dominant production system, and logistic regression analysis showed that socio-economic factors such as training in poultry keeping, household income, income from farming and gender of chicken owners influenced feeding, housing, and health care practices (p<0.05). A large variation in plumage and shank colors, comb types and other phenotypic traits within and between Omani chicken populations were observed. Male and female body weight differed (p<0.05), being $1.3{\pm}0.65$ kg and $1.1{\pm}0.86$ kg respectively. Flock size averaged $22{\pm}7.7$ birds per household with 4.8 hens per cock. Clutch size was $12.3{\pm}2.85$ and annual production $64.5{\pm}2.85$ eggs per hen. Egg hatchability averaged $88{\pm}6.0%$ and annual chicken mortality across all age and sex categories was $16{\pm}1.4%$. The strong involvement of women in chicken keeping makes them key stakeholders in future development and conservation programs, but the latter should be preceded by a comprehensive study of the genetic diversity of the Omani chicken populations.

• Food Science and Biotechnology
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• v.16 no.1
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• pp.116-122
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• 2007

Four compounds with antioxidant activity were isolated from the MeOH extract of peanut shells (pod) and identified as 5,7-dihydroxychromone (1), eriodictyol (2), 3',4',7-trihydroxyflavanone (3), and luteolin (4) by electron impact-mass spectrometry (EI-MS) and nuclear magnetic resonance (NMR) analyses. The relationship between antioxidant activity and chemical structure of the isolated compounds with their analogues [(-)-epicatechin, quercetin, taxifolin] was examined by measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity and using the 2-deoxy-D-ribose degradation system. The order of antioxidant activity on the basis of DPPH radical-scavenging was quercetin = (-)-epicatechin (6.0 molecules) > taxifolin (4,5 molecules) > 4 (luteolin; 4.0 molecules) > 2 (eriodictyol; 2.5 molecules) > 3 (3',4',7-trihydroxy-flavanone; 2.0 molecules) > 1 (5,7-dihydroxychromone; 0.5 molecules). On the other hand, using the 2-deoxy-D-ribose degradation system, the order of antioxidant activity was quercetin > 4 >> (-)-epicatechin ${\geq}\;2\;{\geq}$ taxifolin > 3 > 1. These compounds from peanut shells may provide defensive measures against oxidative stress and insects in the soil.