• 대한본초학회지
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• 제30권2호
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• pp.1-9
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• 2015

Objectives : The present study was conducted to examine whether Toosendan Fructus has an ameliorative effect on diabetes-induced alterations such as oxidative stress and inflammation in the pancreas of non-obese diabetic (NOD) mice, a model of human type I diabetes. Methods : Extracts of Toosendan Fructus (ETF) were administered to NOD mice at three doses (50 mg/kg, 100 mg/kg and 200 mg/kg). Mice at 18 weeks of age were measured glucose tolerance using intraperitoneal glucose tolerance test. After 28 weeks of ETF treatment, glucose, total cholesterol (TC), triglyceride (TG), and proinflammatory cytokines in serum, western blot analyses and a histopathological examination in pancreas tissue, and on the onset of diabetes were investigated. Results : The results showed that levels of glucose, glucose tolerance, TC, TG, interferon-${\gamma}$, interleukin (IL)-1 ${\beta}$, IL-6, and IL-12 in serum were down-regulated, while IL-4, IL-10, SOD, and catalase significantly increased. In addition, ETF improved protein expression of proinflammatory mediaters (such as cyclooxygenase-2, and inducible nitric oxide synthase) and a proapoptotic protein (caspase-3) in the pancreatic tissue. Also, in the groups treated with ETF (100 mg/kg or 200 mg/kg), insulitis and infiltration of granulocytes were alleviated. Conclusions : Based on these results, the anti-diabetic effect of ETF may be due to its anti-inflammatory and antioxidant effect. Our findings support the therapeutic evidence for Toosendan Fructus ameliorating the development of diabetic pancreatic damage via regulating inflammation and apoptosis. Our future studies will be focused on the search for active compounds in these extracts.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2005년도 추계학술발표대회 논문집
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• pp.31-34
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• 2005

For the damage tolerance improvement of conventional laminated composites, stitching process has been utilized for providing through-thickness reinforcements. 2D prefonl1S were stacked with S-2 glass plain weave, and 3D preforms were fabricated using the stitching process. For the matrix system, epoxy and phenol resins were considered. To examine the damage resistance performance the low velocity drop weight impact test has been carried out, and the impact damage was examined by scanning image. CAI (Compressive After Ih1paet) tests were also conducted to evaluate residual compressive strength. Compared with 2D epoxy composites, 2D phenol composites showed drastic reduction in the compressive strength prior to impact because of the higher contents of voids. The damage area of 2D phenol composites were also larger than that of 2D epoxy composites. However, by introducing the stitching, the damage area of 3D phenol composites was reduced by 60%, while the CAI strength improvement was negligible.

• Journal of Plant Biotechnology
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• 제34권4호
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• pp.299-305
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• 2007

산화스트레스 유도성 SWPA2 프로모터 조절하에 항산화 효소 SOD와 APX 유전자를 동시에 엽록체에 발현시킨 형질전환 감자 (품종 수미)를 대상으로 methyl viologen (MV) 처리에 의해 유도되는 산화스트레스 내성을 잎절편체, 소식물체 및 식물체 수준에서 조사하였다. 잎 절편에 $3{\mu}M$ MV를 처리하였을 때 SSA 식물체의 잎절편체는 비형질전환 (NT) 식물체에 비해 40% 정도 상해를 적게 받았다. 소식물체 수준에서 MV에 의한 산화스트레스 내성을 조사하기 위하여 SSA감자 shoot을 $0.3{\mu}M$ MV 첨가 배지에 배양하였을 때 뿌리의 생장에서 내성이 나타났다. 또한 온실에서 4주 생장한 식물체에 $350{\mu}M$ MV를 처리하였을 경우에도 SSA 식물체는 NT 식물체에 비해 약 75% 손상을 적게 입은 것으로 나타내었다. 추후 SSA 식물체를 이용하여 건조, 고온 등의 복합재해에 내성을 분석이 진행되어야 할 것이며 그 결과 복합스트레스 내성 감자 품종 (수미)을 개발할 수 있을 것으로 기대한다.

• 한국산림과학회지
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• 제111권2호
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• pp.251-262
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• 2022

본 연구는 기후변화에 대응하여 남부지역에서 주로 재배되는 차나무 품종인 '참녹', '보향', '상녹', '명녹'을 대상으로 다수의 내한성 지표를 이용하여 신뢰성 있는 평가를 통해 내한성 차나무를 선발하고자 수행하였다. 저온 피해도 조사결과, -10℃에서 '참녹'과 '보향'은 청고 피해가 조사되었고, '상녹'과 '명녹'은 적고 피해가 조사되었다. 전해질 용출량은 처리 온도가 낮아질수록 그 값이 증가하였다. 비선형 회귀 분석을 통해 치사온도를 예측한 결과 '참녹'(-9.344℃), '보향'(-8.883℃)은 '명녹'(-8.092℃), '상녹'(-7.632℃) 보다 상대적으로 내한성이 강한 것으로 나타났다. Proline 분석 결과 '보향'은 다른 품종들에 비교하여 높게 조사되었고, 항산화 활성도 조사 결과 '참녹'과 '보향'이 저온 처리 시 다른 품종과 비교하여 항산화 활성 수치가 높게 나타났다. 지질과산화 반응 측정 결과 '상녹'과 '명녹'은 저온 처리시 다른 품종과 비교하여 MDA 축적 함량이 높았다. 본 연구 결과 '참녹'과 '보향'은 비선형 회귀 분석을 통해 치사온도를 예측한 결과와 저온피해도, 항산화 활성도, 지질과산화 반응과도 일관성 있게 조사되어 내한성이 강한 것으로 나타났다. 본 연구 결과는 기후변화에 대응한 차나무의 내한성 평가와 선발 뿐만 아니라 내한성 식물의 육성에도 활용될 수 있을 것으로 판단된다.

• Structural Engineering and Mechanics
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• 제64권5호
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• pp.557-566
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• 2017

Fiber reinforced polymer (FRP) sheets are the most efficient structural materials in terms of strength to weight ratio and its application in strengthening and retrofitting of a structure or structural elements are inevitable. The performance enhancement of structural elements without increasing the cross sectional area and flexible nature are the major advantages of FRP in retrofitting/strengthening work. This research article presents a detailed study on the inelastic response of conventional and retrofitted Reinforced Concrete (RC) frames using Carbon Fibre Reinforced Polymers (CFRP) and Glass Fiber Reinforced Polymers (GFRP) subjected to quasi-static loading. The hysteretic behaviour, stiffness degradation, energy dissipation and damage index are the parameters employed to analyse the efficacy of FRP strengthening of brick in-filled RC frames. Repair and retrofitting of brick infilled RC frame shows an improved load carrying and damage tolerance capacity than control frame.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.253-256
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• 2006

The HPFRCCs show the multiple crack and damage tolerance capacity due to the interfacial bonding of the fibers to the cement matrix. For practical application, it is needed to investigate the fractural behavior and of HPFRCCs and understand the micro-mechanism of cement matrix with reinforcing fiber. The objectives of this paper are to examine the compressive behavior, fracture and damage process of HPFRCC by acoustic emission technique. Total four series were tested, and the main variables were the hybrid type, polyethylene (PE) and steel cord (SC), and fiber volume fraction. The damage progress by compressive behavior of the HPFRCCs is characteristic for the hybrid fiber type and volume fraction. And from acoustic emission (AE) parameter value, it is found that the second and third compressive load cycles resulted in successive decrease of the ring-down count rate as compared with the first compressive load cycle.

• International Journal of Fluid Machinery and Systems
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• 제3권4호
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• pp.301-308
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• 2010

Quest for reliability of hydraulic runners is a concern for all mature electricity producers. The fatigue damage caused by dynamics loads is frequently the root cause of runner failure. This paper presents the damage tolerance approach based on fracture mechanics as the method chosen by Alstom and Hydro-Qu$\acute{e}$bec to predict effects of damage on runner lifetime and consequently to be use as a design method. This is sustained by a research on fracture mechanics properties of runner materials and by recommendations on the strategy to define a safety margin for design. The acquired knowledge permits to identify potential improvement of the runner lifetime without significant cost increase, like being more specific on some chemical composition or heat treatment.

• Structural Engineering and Mechanics
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• 제73권4호
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• pp.381-395
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• 2020

Study on the inelastic response of bare and masonry infilled Reinforced Concrete (RC) frames repaired using Carbon Fibre Reinforced Polymers (CFRP) and Glass Fiber Reinforced Polymers (GFRP) subjected to quasi- static loading is presented in the work. The hysteresis behaviour, stiffness retention, energy dissipation and damage index are the parameters employed to analyze the efficacy of FRP strengthening of bare and brick in-filled RC frames. It is observed that there is a significant improvement in load carrying capacity of brick infilled frame over bare RC frame. Also FRP strengthened brick infilled frame performs much better than FRP repaired bare frame under quasi static loading. Repair and retrofitting of brick infilled RC frame shows an improved load carrying and damage tolerance capacity than control frame.

• Journal of Plant Biotechnology
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• 제6권4호
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• pp.205-212
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• 2004

The objectives were to compare the salt tolerance levels in the parental rice cultivar, Dongjinbyeo, and induced mutagenesis derived its lines for plant height, MDA, ATPase, POD, and 2-dimensional protein electrophoresis pattern in NaCl-containing hydroponic nutrient solutions. Rice plants isolated from a population of rice (Oryza sativa L. cv. Dongjinbyeo) mutation lines, which were generated in combination with in vitro selection and gamma-ray, exhibited salt tolerance. Line No. 18 had the longest plant, whereas NaCl-sensitive line (No. 25) had the shortest plant. The parent, and the sensitive line showed severe damage from salt stress. Tolerant lines (No. 18, 50) had a lower malonaldehyde (MDA) content than the sensitive one (Dongjinbyeo, No. 25) during salt stress. Several proteins showed significant quantitative variation through 2DE; phosphoribulokinase, peroxidase, oxygen evolving enhancer 1 and the $H^+-ATPase$, which are known to be involved in salt tolerance. The effect of salt on peroxidase and $H^+-ATPase$ activity in the seedlings of two groups with contrasting genotypes of rice was studied. A greater activity was recorded in the tolerant lines as compared to the sensitive ones (P<0.05, Duncan's test). The results indicate that salt tolerant lines expressed more salt stress-inducible proteins associated with salt tolerance than the sensitive lines during salt stress.

• Journal of Microbiology and Biotechnology
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• 제23권12호
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• pp.1737-1746
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• 2013

IbMYB1, a transcription factor (TF) for R2R3-type MYB TFs, is a key regulator of anthocyanin biosynthesis during storage of sweet potatoes. Anthocyanins provide important antioxidants of nutritional value to humans, and also protect plants from oxidative stress. This study aimed to increase transgenic potatoes' (Solanum tuberosum cv. LongShu No.3) tolerance to environmental stress and enhance their nutritional value. Transgenic potato plants expressing IbMYB1 genes under the control of an oxidative stress-inducible peroxidase (SWPA2) promoter (referred to as SM plants) were successfully generated through Agrobacterium-mediated transformation. Two representative transgenic SM5 and SM12 lines were evaluated for enhanced tolerance to salinity, UV-B rays, and drought conditions. Following treatment of 100 mM NaCl, seedlings of SM5 and SM12 lines showed less root damage and more shoot growth than control lines expressing only an empty vector. Transgenic potato plants in pots treated with 400 mM NaCl showed high amounts of secondary metabolites, including phenols, anthocyanins, and flavonoids, compared with control plants. After treatment of 400 mM NaCl, transgenic potato plants also showed high DDPH radical scavenging activity and high PS II photochemical efficiency compared with the control line. Furthermore, following treatment of NaCl, UV-B, and drought stress, the expression levels of IbMYB1 and several structural genes in the flavonoid biosynthesis such as CHS, DFR, and ANS in transgenic plants were found to be correlated with plant phenotype. The results suggest that enhanced IbMYB1 expression affects secondary metabolism, which leads to improved tolerance ability in transgenic potatoes.