• 제목/요약/키워드: Damage Tolerance

검색결과 319건 처리시간 0.027초

Relationship between Fatty Acid Composition of Phospholipid from Leaves and Cold Tolerance of Rice Plants (벼의 내냉성과 잎조직인지질의 지방산 조성과의 상관관계)

  • Jung, Jin;Kim, Young-Kee;Park, Sang-Gyu
    • Applied Biological Chemistry
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    • 제26권1호
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    • pp.58-64
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    • 1983
  • The fatty acid composition of phospholipid from the leaves of rice plants grown at $28^{\circ}C$ and harvested at the 3-4 leaf stage was determined for 8 cultivars. Change among cultivars observed in the composition has been found to be correlative to the chilling susceptivity of the plants at the given leaf-stage. The chilling-resistant cultivars contain phospholipid with higher degree of unsaturation and larger relative proportion of unsaturated fatty acids than the chilling-sensitive ones. The indices for unsaturation of phospholipid from a cultic-ar are well in accordance with its resistance to cold damage. clearly demonstrating that the fluidity of biomembrane which is generally regarded as the prerequisite for a cell to maintain its membrane-related physiological activity at a low temperature is exclusively controlled by the fatty acid composition of phospholipid. Also identified were the components of phospholipid, which are phosphatidyl serine and phosphatidyl coline as major components and phosphatidyl inositol as minor component plus 3 phospholipids in trace proportion, from every cultivar at the early growth-stage.

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Hypoglycemic Effects of Germinated Rough Rice Extract in Streptozotocin-induced Diabetic Rats

  • Lee, Youn-Ri;Hwang, In-Guk;Woo, Koan-Sik;Kim, Hyun-Young;Park, Dong-Sik;Kim, Jae-Hyun;Kim, Yun-Bae;Lee, Jun-Soo;Jeong, Heon-Sang
    • Preventive Nutrition and Food Science
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    • 제16권3호
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    • pp.272-277
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    • 2011
  • The hypoglycemic effects of germinated rough rice extract in streptozotocin (STZ)-induced diabetic rats were investigated. Weight gain was significantly lower in the diabetic groups than in the normal control (NC); however, they were higher in the 1% and 3% diabetic groups given germinated Goami2 rough rice extract (DM-3%GGRRE) than in the diabetic control (DC). While food intake in all diabetic groups was significantly higher than that of the NC, there was no significant difference among all diabetic groups. The weight percentages of liver and kidney in all diabetic groups were significantly higher than that of the NC. In terms of blood glucose, the diabetic group showed about a three times larger value than the normal group. Moreover, in the 3% germinated rough rice extract group, the blood glucose level became lowered. The levels of alanine transaminase, aspartate transaminase, blood urea nitrogen, creatinine phosphokinsae, and creatinine increased in general with the induction of diabetes using STZ; however, the 3% GGRRE-treated group displayed a significant decrease in these levels compared to the diabetic group. The results show that the 3% GGRRE, rather than the 1% GGRRE, was considerably more effective at reducing blood glucose and improving impaired glucose tolerance, suggesting the germinated rice extracts may play a role in preventing liver and kidney damage.

Flexural and Tensile Performance of Strain-Hardening Cement Composite with Synthetic Fibers (합성섬유를 사용한 변형경화형 시멘트 복합체의 휨 및 인장성능)

  • Kim, Sun-Woo;Lee, Min-Jung;Jang, Yong-Heon;Jang, Gwang-Soo;Song, Seon-Hwa;Yun, Hyun-Do
    • Proceedings of the Korea Concrete Institute Conference
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    • 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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    • pp.925-928
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    • 2008
  • Fiber is an important ingredient in strain-hardening cementitious composite (SHCC), which can control fracture of cementitious composite by bridging action. The properties of reinforcing fiber, as tensile strength, aspect ratio and elastic modulus, have great effect on the fracture behavior of SHCC. To apply SHCC to structural member, SHCC must have economical efficiency and workability as well as own excellent tensile performance. For these purposes, four-point bending and direct tensile tests on SHCC with only hybrid synthetic fibers, total fiber volume fraction, $V_f$, is 1.5%, are carried out. The research emphasis is on the mechanical properties of SHCC made in Polyvinyl alcohol (PVA) and Polyethylene (PE) fibers, and how this affects the composite property, and ultimately its strain-hardening performance. Also, effect of hybrid type and water-cement ratio on the behavior of SHCC was evaluated in this paper.

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Enhanced Resistance of Transgenic Sweetpotato (Ipomoea batatas Lam.) Plants to Multiple Environmental Stresses Treated with Combination of Water Stress, High Light and High Temperature Stresses

  • Song, Sun-Wha;Kwak, Sang-Soo;Lim, Soon;Kwon, Suk-Yoon;Lee, Haeng-Soon;Park, Yong-Mok
    • Journal of Ecology and Environment
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    • 제29권5호
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    • pp.479-484
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    • 2006
  • Ecophysiological parameters of non-transgenic sweetpotato (NT) and transgenic sweetpotato (SSA) plants were compared to evaluate their resistance to multiple environmental stresses. Stomatal conductance and transpiration rate in NT plants decreased markedly from Day 6 after water was withheld, whereas those values in SSA plants showed relatively higher level during this period. Osmotic potential in SSA plants was reduced more negatively as leaf water potential decreased from Day 8 after dehydration treatment, while such reduction was not shown in NT plants under water stressed condition. SSA plants showed less membrane damage than in NT plants. As water stress and high light stress, were synchronously applied to NT and SSA plants maximal photochemical efficiency of PS II ($F_v/F_m$) in NT plants markedly decreased, while that in SSA plants was maintained relatively higher level. This trend of changes in $F_v/F_m$ between SSA plants and NT plants was more conspicuous as simultaneously treated with water stress, high light and high temperature stress. These results indicate that SSA plants are more resistive than NT plants to multiple environmental stresses and the enhanced resistive characteristics in SSA plants are based on osmotic adjustment under water stress condition and tolerance of membrane.

Evaluation of SHCC on Direct Tensile Load using Acoustic Emission Technique (음향방출기법을 이용한 혼입되는 섬유의 종류에 따른 SHCC의 직접인장거동특성 평가)

  • Kim, Yun-Su;Yun, Hyun-Do;Jeon, Esther;Park, Wan-Shin
    • Proceedings of the Korea Concrete Institute Conference
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    • 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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    • pp.177-180
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    • 2008
  • SHCC shows the high energy tolerance capacity due to the interfacial bonding of the fibers to the cement matrix. For effective material design and application of SHCC, it is needed to investigate the damage process and micro-fracture mechanism of cement matrix reinforced with different types of fibers. The objective of this paper is to investigate the direct tensile response of cement composites reinforced with single and hybrid fibers using acoustic emission(AE) technique. In this study, the correlations between AE signal and result of the direct tensile response of SHCC. For these purposes, three kinds of fibers were used: PET1.5%, PET1.0+PE0.5%, PET1.0%+PVA0.5%. The result of the direct tensile response of SHCC, for the same volume fraction of fibers, ultimate strength of PET-PE specimen was 2.7 times higher than specimens with PET fibers. And from AE signal value, AE event numbers and cumulative energy were different according to kind of fiber because of the different material properties of reinforced fiber.

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Safety Enhancement of LPG Terminal by LOPA & SIF Method (LOPA 및 SIF기법에 의한 LPG 인수기지의 안전성향상에 대한 연구)

  • Lee, Il Jae;Kim, Rae Hyun
    • Korean Chemical Engineering Research
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    • 제53권4호
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    • pp.431-439
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    • 2015
  • The methods which decrease the accident hazards of LPG(Liquefied Petroleum Gas) terminal on the basis of butane & propane storage tanks by applying HAZOP(Hazard and Operability), LOPA(Layer of Protection Analysis) and SIL(Safety Integrity Level) are suggested. The accident scenarios were derived by analyzing latent risks through the HAZOP. The scenarios which would have the big damage effect in accidents were selected and then LOPA was assessed by analyzing IPL(Independent Protection Layer) about the correspond accident scenarios. The improved methods were proposed on the basis of level of SIF(Safety Instrumented Functions) as a IPL considering satisfied condition of risk tolerance criteria($1.0{\times}10^{-05}/y$). In addition, The proposed IPLs were basis on the economic analysis. The effect of SIF as a IPL considering the changes of accident frequency was studied in case of the accident scenarios derived from the concerned process.

Numerical and Experimental Investigation on Impact Performance of Fiber Metal Laminates Based on Thermoplastic Composites (열가소성 복합재료를 기반한 섬유금속적층판의 충격 거동에 관한 실험 및 수치적 연구)

  • Lee, Byoung-Eon;Kang, Dong-Sik;Park, Eu-Tteum;Kim, Jeong;Kang, Beom-Soo;Song, Woo-Jin
    • Transactions of the Korean Society of Automotive Engineers
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    • 제24권5호
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    • pp.566-574
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    • 2016
  • Fiber metal laminates, which are hybrid materials consisting of metal sheets and composite layers, have contributed to aerospace and automotive industries due to their reduced weight and improved damage tolerance characteristics. In this study, the impact performance of the laminates, which are comprised of a self-reinforced polypropylene and two aluminum sheets, and the pure aluminum alloy sheet material were investigated experimentally via numerical simulation. In order to compare the impact performance, the laminates and aluminum alloy were examined by assessing the impact force, energy time histories, and specific energy absorption. ABAQUS is a commercial software that is used to simulate the actual drop-weight tests. Based on this study, it is noted that the impact performance of the laminates was superior to that of the aluminum alloy. In addition, a good agreement between the experimental and numerical results can be achieved when the impact force and energy time histories from the experiments and the numerical simulations are compared.

A Development of 3D Penetration Analysis Program for Survivability Analysis of Combat System : Focused on Tank Model (전투 시스템 생존성 분석을 위한 3차원 관통 해석 프로그램 개발 : 전차 모델을 대상으로)

  • Hwang, Hun-Gyu;Lee, Jae-Woong;Lee, Jang-Se;Park, Jong-Sou
    • Journal of the Korea Institute of Information and Communication Engineering
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    • 제19권1호
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    • pp.244-250
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    • 2015
  • Survivability is avoidance and tolerance ability of combat systems for accomplishing mission in battle field. Therefore, the combat system has to protect or minimize any damage from threats. For this reason, many modeling and simulation based studies which analyze vulnerability of the combat system by threats, are in progress to improve survivability of the combat system. In this paper, we developed a 3D penetration analysis program for survivability analysis of combat system. To do this, we applied the penetration analysis equation to threat and protection performance of tank. Also we implemented simple tank models based on 3D CAD, and tested the developed program using the implemented tank models. As a result, we verified the developed program that is possible to analyze penetration by threat and protection performance of tank and to visualize its result, based on scenarios.

Growing pigs developed different types of diabetes induced by streptozotocin depending on their transcription factor 7-like 2 gene polymorphisms

  • Tu, Ching-Fu;Hsu, Chi-Yun;Lee, Meng-Hwan;Jiang, Bo-Hui;Guo, Shyh-Forng;Lin, Chai-Ching;Yang, Tien-Shuh
    • Laboraroty Animal Research
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    • 제34권4호
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    • pp.185-194
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    • 2018
  • The different polymorphisms of the transcription factor 7-like 2 (TCF7L2) gene promote variances in diabetes susceptibility in humans. We investigated whether these genotypes also promote differences in diabetic susceptibility in commercial pigs. Growing pigs (Landrace, both sex, 50-60 kg) with the C/C (n=4) and T/T (n=5) TCF7L2 genotypes were identified and intravenously injected with streptozotocin (STZ, 40 mg/kg) twice in weekly intervals, then a high-energy diet was offered. Oral glucose tolerance tests, blood analyses and the homeostasis model assessment-insulin resistance (HOMA-IR) index calculations were performed. The animals were sacrificed at the end of 12 weeks of treatment to reveal the pancreas histomorphometry. The results showed that all of the treated pigs grew normally despite exhibiting hyperglycemia at two weeks after the induction. The glycemic level of the fasting or postprandial pigs gradually returned to normal. The fasting insulin concentration was significantly decreased for the T/T carriers but not for the C/C carriers, and the resulting HOMA-IR index was significantly increased for the C/C genotype, indicating that the models of insulin dependence and resistance were respectively developed by T/T and C/C carriers. The histopathological results illustrated a significant reduction in the pancreas mass and insulin active sites, which suggested increased damage. The results obtained here could not be compared with previous studies because the TCF7L2 background has not been reported. Growing pigs may be an excellent model for diabetic in children if the animals are genetically pre-selected.

Concentration and risk assessment of indoor air quality in day care centers and postnatal care centers (보육시설, 산후조리원의 실내공기질 농도 및 위해성평가)

  • An, Jihee;Oh, Yujin;Im, Ji Young;Ahn, Mun Seob;Hong, Eunju;Son, Bu-Soon
    • Journal of odor and indoor environment
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    • 제17권4호
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    • pp.337-345
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    • 2018
  • In this study, we measured the concentration of Particulate Matter($PM_{10}$), Formaldehyde(HCHO), and Total Bacteria Count (TBC) at two facilities: day care centers, and postnatal care centers located in the cities of Gyeonggi, Gangwon, Jeolla and Gyeongsang from January 1, 2012 to December 31, 2015. $PM_{10}$ concentration was similar to the day care centers and postnatal care centers. HCHO concentration was the highest in the postnatal care centers. TBC concentration was the highest in the day care centers. Comparing the different cities, $PM_{10}$ concentration was the highest in Gyeonggi, HCHO concentration was the highest in Gyeonggi, and TBC concentration was the highest in Gyeonggi. As a result of HCHO's risk assessment, it was found that adults exceeded the carcinogenicity tolerance of $10^{-6}$ specified by the US EPA. This study is expected to be helpful in preventing damage to health from the contaminated indoor air at sensitive facilities, and can be used as basic data for indoor air quality management.