• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.2
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• pp.108-112
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• 2003

Foehn damage on rice plant is one of the important abiotic stresses in eastern costal area of Korea. To know the relationship between foehn impact and morphological traits of rice, wind tunnel method was used with 106 rice cultivars. Less influencing traits on foehn were short panicle, large panicle number per hill, thin panicle neck, and the flag leaf of narrow, short and thick. Leaf pubescence reduced the impact on foehn. 'Naepungbyeo' belong-ed to foehn tolerant varietal group, while 'Ansanbyeo' belonged to the opposite group. Three levels of root cutting treatment with two rice cultivars were conducted to evaluate the foehn impact using wind tunnel. The severity of wind damages was followed the sigmoidal curve duration of wind tunnel treatment were prolonged. Different responses of root cutting to wind tunnel treatment could be used to evaluate the severity of the foehn impact. 'Naepungbyeo' was one of the less implausible cultivars on foehn. 'Nae-pungbyeo' showed tolerant response to wind under 21% root removing treat-ment (20㎝ root cutting), however 'Ansanbyeo' was wilted under the same treatment. In case of 35 % root removing treatment(10㎝ root cutting), both rice cultivars failed to alive against foehn wind.

• The korean journal of orthodontics
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• v.49 no.2
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• pp.106-115
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• 2019

Objective: This study aimed to evaluate the effects of force loading on root damage caused by contact with temporary anchorage devices (TADs) during orthodontic treatment and to examine the repair process 4, 8, and 12 weeks after TAD contact by micro-computed tomography (CT). Methods: We enrolled 42 volunteers who required bilateral upper first premolar extractions. The experimental study design was as follows. For both first premolars, cantilever springs were placed, and then TADs were immediately inserted between the premolars of all volunteers. According to the removal order of the appliances, the participants were divided into the TAD group (Group T: n = 21, only TAD removal) and the spring group (Group S: n = 21, only spring removal). A splitmouth design was adopted in both groups as follows. For each volunteer, the left premolars were extracted 4, 8, or 12 weeks after TAD-root contact. The right premolars were extracted immediately after contact in both groups (Groups T-C and S-C) and used as positive controls. Resorption volumes and numbers of craters were determined by micro-CT. Results: The numbers of resorption craters were higher in Group T than in Group S at 8 and 12 weeks (p < 0.01). Crater volumes were higher in Group T than in Group S at 4 and 12 weeks (p < 0.01, both). Conclusions: Root injury was not completely repaired 12 weeks after root-TAD contact, even when the TADs were removed in cases of continuous force application.

• Structural Monitoring and Maintenance
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• v.5 no.2
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• pp.231-242
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• 2018

Subway tunnel structure has been rapidly developed in many cities for its strong transport capacity. The model-based damage detection of subway tunnel structure is usually difficult due to the complex modeling of soil-structure interaction, the indetermination of boundary and so on. This paper proposes a new data-based method for the damage detection of subway tunnel structure. The root mean square acceleration and cross correlation function are used to derive a statistical pattern recognition algorithm for damage detection. A damage sensitive feature is proposed based on the root mean square deviations of the cross correlation functions. X-bar control charts are utilized to monitor the variation of the damage sensitive features before and after damage. The proposed algorithm is validated by the experiment of a full-scale two-rings subway tunnel lining, and damages are simulated by loosening the connection bolts of the rings. The results verify that root mean square deviation is sensitive to bolt loosening in the tunnel lining and X-bar control charts are feasible to be used in damage detection. The proposed data-based damage detection method is applicable to the online structural health monitoring system of subway tunnel lining.

• Journal of Forest and Environmental Science
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• v.26 no.3
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• pp.193-202
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• 2010

To analyze the effects of tree roots on the stability of damage slope, distributional and physical properties of five-year Pinus densiflora roots were investigated. In the composition of roots, the proportion of main root to lateral root was 1 to 9 in slope condition. Root tensile force was increased in accordance with increased proportion to diameter of Pinus densiflora roots. However, tensile strength was decreased in proportion to diameter of roots. Root shear strength showed that soil containing Pinus densiflora roots was higher than that of non-treated soils. This result shows that Pinus densiflora roots significantly stabilize the surface-soil rather than sub-soil in damage slopes.

• Journal of Ginseng Research
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• v.20 no.2
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• pp.179-183
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• 1996

One exotherm was detected in the intact ginseng seeds containing more than 35% water, but in seeds with 20% there was no exotherm. The shapes of exotherm were remarkably uniform without relation to water content above 35%. The temperature at the initiation of freezing varied from -3.5$^{\circ}C$ to -9.6$^{\circ}C$ with the different water content in the seeds, and the Initial temperature of freezing delayed with the decrease of water content. The resistance damage at low temperature appeared in order of maln body, rhizome, lateral root of 3-year-old yearling rhizome, and fine root of 3-year-old. Ginseng roots didn't receive any damage at -5$^{\circ}C$ for 24 hours. Otherwise they received serious damage below -1$0^{\circ}C$ even for 5 hours'exposure. Hence, alternative low temperature gave more severe damage compared to constant low temperature. This result suggests that the Possibility of receiving injury at low temperature was higher during the thawing season of the early spring than in the winter.

• Journal of Applied Biological Chemistry
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• v.61 no.2
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• pp.109-117
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• 2018

Recently, cancer incidence in modern society is increasing sharply. DNA damage is caused by intrinsic or extrinsic factors in the human body, cells protect themselves by defense mechanism against DNA damage. Also, Aberrant DNA and deficient DNA repair are closely associated with various diseases, including aging and cancer. Researchers are interested in search for proper materials to inhibition for DNA damage. As knew the side effects of synthetic antioxidant, some researches have been conducted about cancer prevention materials derived from nature. Root of Smilax china, in Liliaceae, is used detoxification and tumor treatments traditionally. However, studies on the inhibitory effect of DNA damage haven't progressed. In this study, antioxidant activity and protective effects on oxidative DNA damage of S. china root were confirmed, relationship between those activities and contents of phenolic compounds in plants were established. S. china root effectively removed 1,1-diphenyl-2-picryl-hydrazyl radicals and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid radicals. The quantification and identification of phenolic compounds were confirmed by high performance liquid chromatography analysis, its antioxidant activity was associated with some phenolic compounds. In addition, protective effects against hydroxyl radicals and ferrous ion-induced oxidative DNA damage were confirmed in plasmid DNA. In the cellular levels, S. china root suppressed the expression of ${\gamma}$-H2AX and p53 protein in NIH 3T3. Besides, S. china root suppressed H2AX and p53 mRNA levels. In conclusion, S. china root had the effect on DNA protection and antioxidant.

• Korean Journal of Veterinary Research
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• v.47 no.1
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• pp.25-32
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• 2007

Houttuynia cordata root on non-lipid oxidative damage. The antioxidative efects of methanolic (MeOH) extract of Houttuynia cordata rooton non-lipid, including liposome oxidation, oxidation of deoxyribose, protein oxidation, chelating, scavenging,and 2'-deoxyguanosine (2'dG) oxidation were investigated. Houttuynia cordata root exhibited highantioxidative effect in a liposome model system. The inhibitory effect of MeOH extract on deoxyribosedamage exhibited antioxidative effect and it afforded considerable protection against damage to deoxyribose.In addition, MeOH extract at over 300extracts exhibited metal binding ability for hydrogen peroxide. Furthermore, the oxidation of 2'dG to 8-hydroxy-2-deoxyguanosine was inhibited by MeOH extracts, and scavenging activity for hydroxyl radicalexhibited a remarkable effect. The present results on biological model systems showed that MeOH extractswas effective in the protection of non-lipids against various oxidative model systems.

• The Plant Pathology Journal
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• v.25 no.3
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• pp.231-235
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• 2009

Viral infections and root growth were examined to elucidate the relationship between viral resistance and root growth in 26 Korean hulless barley cultivars. Viral resistance was estimated in experimental filed of Honam agricultural research institute for 3 years. Length and number of seminal and adventitious roots were examined for evaluation of root growth in both field and green-house conditions 30 days after seeding. Dominant viral infection occurred in Korean hulless barley by Barley yellow mosaic virus (BaYMV) in fields; however, susceptible cultivars were infected by either BaYMV, Barley mild mosaic virus (BaMMV) or both. Only four cultivars, including Donghanchalssalbori, Kwangwhalssalbori, Namhossalbori and Naehanssalbori, presented stable resistance to viral infections. Susceptible cultivars to viral infection in fields showed shorter seminal root length and fewer adventitious root number than resistant cultivars. Resistant cultivars showed better root growth and significant difference in adventitious root length in green house conditions. Increase in the number of seminal roots in resistant cultivars was derived from decreased damage of roots by the viral infection compared to the susceptible cultivars.

• Journal of Ginseng Research
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• v.27 no.3
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• pp.141-145
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• 2003

The multi-year production cycle for ginseng can be rapidly depreciated by inferior post-harvest activities. This research examines the character of high temperature drying regimes for North American ginseng root to assist management decision making. The objective is a very rapid drying regime, that will not result in physical or chemical damage to the root and that would not alter the actual dry root weight. Research is presented using drying temperatures of 55, 70 and 105 C. Temperatures above these rapidly cause substantive physical damage to the root samples and seriously compromise the dry root values determined. Temperatures below these behaved quite similar to actual dryer regimes (approximately 38 C). Laboratory results indicate that there are differences between the three temperature regimes tested. Careful usage of the 70 C regime, over a period of two to three days in a convection drying oven, has distinct merit.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.6
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• pp.950-955
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• 2010

In this study, we prepared CheonJeongKiBo-Dan(7 oriental medicinal plants, 7OMP: Astragalus Membranaceus root, Panax Ginseng root, Glycyrrhiza Glabra (licorice) root, Schizandra Chinensis fruit, Polygonatum Odoratum, Rehmannia Glutinosa root, Paeonia Albiflora root) by extracting them in one reactor and studied its efficacies on skin. UV irradiation has been suggested as a major cause of photoaging in skin. In order to investigate protective effects against UV-B induced cellular damage, 7OMP was extracted with 70% ethanol and dissolved in DMSO. The protective effect was detected by MTT assay, reactive oxygen species (ROS) generation, phosphorylation of ATR and p53 in human dermal fibroblast cell system after UV-B irradiation. 7OMP reduced UV-B-induced cellular damage in HDFs cells, and inhibited ROS generation. UV-B-induced toxicity accompanying ROS production and the resultant DNA damage are responsible for activation of ATR, p53 and Bad. In this study, 7OMP hampered phosphorylations of ATR and p53 in human dermal fibroblasts. Therefore, 7OMP may be protective against UV-induced skin photoaging.