• Composites Research
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• 제36권2호
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• pp.86-91
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• 2023

Thermoplastic polyurethane (TPU) is a material whose mechanical properties change according to the phase separation of its unique internal microstructure and is therefore used in various industries. Use of TPU as composites helps in improving the desirable characteristics and properties in accordance with usage. Eco-friendly fillers one of the fillers are on the rise and those are mostly used for reinforcing role. Suberin, which can be extracted from cork, is the main component of cork. It is known to serve high damping property of elastomer composite. The original chemical structure of Suberin is an aliphatic polyester aggregate. In this research, Suberin is obtained after depolymerization into an oligomer having 2 or 3 ester bonds through alkaline hydrolysis. The extracted suberin was added to the matrix which is thermoplastic polyurethane as an eco-friendly filler for improving vibration damping property. As a result, when 10 wt% of suberin was added into thermoplastic polyurethane the existing trade-off relationship was overcome. And it is attained the elastic modulus and damping factor at room temperature improving 92 and 59%, respectively, compared to the original matrix. Those results are from the interaction between the microstructure of TPU and suberin.

• 한국응용곤충학회지
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• 제16권1호
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• pp.55-63
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• 1977

감자 저장병으로서 중요한 Fusarium solani, F. roscum, F. oxysporum 및 Erwinia carotovora를 분리 동정하고 수확후에 공시품종 Epicure, Irish Cobbler, 및 Superior의 괴경을 절단하여 $4^{\circ},\;14^{\circ},\;24^{\circ},\;및\; 34^{\circ}$ 각 온도의 습실에 1, 3, 5, 및 7일간 예치한 후 suberin 및 periderm 형성을 검경하였다. 그리고 위와 같이 처리한 괴경에 4종의 병원균을 접종하여 9일간 정치한 후 부패도를 조사하였다. 예치온도가 높을수록 또 그 기간이 길어짐에 따라 보호막으로서의 suberin 및 periderm 형성이 증가하였으며 부패는 감소되었다. 공시균종간의 병원성, 품종에 대한 반응, 보호막 형성에도 차이가 있었으나 예치온도 및 기간의 효과가 부패방지에 더 중요하였다. $4^{\circ}C$에서는 7일이내의 예치기간에 보호막은 거의 형성되지 않았으며 부패는 심하였고 $34^{\circ}C$에서는 대체로 이와 반대하였다. 그러므로 절상감자를 바로 $4^{\circ}C$에 냉장함은 피해여야 할 것으로 본다. $24^{\circ}C$에서 3일 $14^{\circ}C$에서 5일이 지나면 부패되지 않았으며 suberin 및 periderm 형성은 중정도였다. 고온에서는 예치, 기간중에 기경이 부패되는 수도 있으므로 그 적온을 피하여 $14^{\circ}C$에 5일 이상 예치한 후에 저장하는 것이 실용적이라 생각된다.

• Journal of Applied Biological Chemistry
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• 제50권4호
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• pp.288-292
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• 2007

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.35-35
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• 2017

How do plants take up water from soils especially when water is scarce in soils? Plants have a strategy to respond to water deficit to manage water necessary for their survival and growth. Plants regulate water transport inside them. Water flows inside the plant via (i) apoplastic pathway including xylem vessel and cell wall and (ii) cell-to-cell pathway including water channels sitting in cell membrane (aquaporins). Water transport across the root and leaf is explained by a composite transport model including those pathways. Modification of the components in those pathways to change their hydraulic conductivity can regulate water uptake and management. Apoplastic barrier is modified by producing Casparian band and suberin lamellae. These structures contain suberin known to be hydrophobic. Barley roots with more suberin content from the apoplast showed lower root hydraulic conductivity. Root hydraulic conductivity was measured by a root pressure probe. Plant root builds apoplastic barrier to prevent water loss into dry soil. Water transport in plant is also regulated in the cell-to-cell pathway via aquaporin, which has received a great attention after its discovery in early 1990s. Aquaporins in plants are known to open or close to regulate water transport in response to biotic and/or abiotic stresses including water deficit. Aquaporins in a corn leaf were opened by illumination in the beginning, however, closed in response to the following leaf water potential decrease. The evidence was provided by cell hydraulic conductivity measurement using a cell pressure probe. Changing the hydraulic conductivity of plant organ such as root and leaf has an impact not only on the speed of water transport across the plant but also on the water potential inside the plant, which means plant water uptake pattern from soil could be differentiated. This was demonstrated by a computer simulation with 3-D root structure having root hydraulic conductivity information and soil. The model study indicated that the root hydraulic conductivity plays an important role to determine the water uptake from soil with suboptimal water, although soil hydraulic conductivity also interplayed.

• Journal of the Korean Wood Science and Technology
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• 제16권2호
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• pp.90-97
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• 1988

The rate of utilization of the oak cork (bark of Quercus variabilis Blume) ranges only 40-50%. Therefore, this study was carried out to investigate the chemical properties of the oak cork for increasing the utility. 1) The contents of alkali extractives, organic solvent extractives and ash in the oak cork are similar to those of other barks, but hot and cold water extractives and lignin contents are lower than those of the wood. The carbohydrate (cellulose and hemicellulose) content of the oak cork is similar to that of other barks. The suberin contents in the first and the second bark of the oak cork are 34.8 and 32.2% respectively, in the dry weight. 2) Inorganic component contents of the first bark are similar to those of the second. The pH of the first and the second bark are 3.9 and 4.2%. The caloric values of the first and second bark are 6,263 Kcal/kg, and 5,828 Kcal/kg, respectively, and these caloric values are higher than those of other barks. The sclerencymatous cell content of the first bark which is related to the quality of the oak cork is lower than that of second bark, the contents of the sclerenchymatous cell and lignin show the positive correlation. 3) In the dimension of the cross sectioned cork cell, the first bark is bigger than that of the second. The shape of the cork cell is globular shape in the early bark and discoid shape in the late bark. The cross and the radial section are the same shape, but the tangential section shows difference from the other section.

• 한국식물병리학회지
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• 제2권1호
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• pp.37-42
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• 1986

[ $0.5\%$ ] lactophenol acid fuchsin으로 염색해 본 결과 보리흰가루 병균의 제1차 발아관에 반응하여 보리표피 세포에 papillae 및 cytoplasmic aggregate가 형성되었으나 그 크기는 부착기에 반응하여 형성된 것보다는 훨씬 작았으며 또한 접종후 36-48시간 이후의 표피세포내에는 acid fuchsin에 의해서 다른 세포들에 비해 세포전체가 좀 더 진하게 염색되는 곳이 군데군데 관찰되었다. 그러나 접종 후 96시간까지 지질과산화산물의 일종인 malondialdehyde의 함량은 증가하지 않았다. 접종 후 6시간에 형성된 papillae 및 cytoplasmic aggregate내에 callose, protein, phenol물질 등은 집적되었으나 접종 후 72시간까지도 cellulose, cutin, suberin, lignin등은 검출되지 않았다. 보리-흰가루병 상호조합의 상기 모든 반응은 race 비특이적이었다.

• Journal of Ginseng Research
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• 제19권1호
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• pp.77-83
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• 1995

This study was conducted to investigate the chemical components of rusty root for seeking the cause of rust. Na, Fe contents were higher in various tissues of six-year-old rusty root than healthy root. Contents of total sugar in epidermis of rusty root was low but crude lignin and suborn contents were high. Crude lipid content increased with the rate of rusty symptoms in each part of root respectively. Pentadecanoic, stearic, oleic, lignoseric acid contents increased in cortex of tap root with the rate of rusty symptoms but decreased in pith. Total ginsenoside and crude saponin contents increased , in pith and cortex of tap root with the rate of rusty symptoms but decreased in lateral and fine root.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.5-5
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• 2017

Too little and too much water due to climatic events is a significant cause of global food insecurity. Crops are less productive under water-limited conditions and all major crops, with the exception of rice (Oryza sativa), die within a few days of complete submergence. To complement our studies on genes such as SUB1A, (an ERF-VII transcription factor that provides robust submergence tolerance) and AG1 (a TREHALOSE 6-P PHOSPHATASE that promotes establishment of young seedlings underwater), we have retooled INTACT (${\underline{I}}solation$ of ${\underline{N}}uclei$ ${\underline{TA}}gged$ in specific ${\underline{C}}ell$ ${\underline{T}}ypes$) and TRAP (${\underline{T}}ranslating$ ${\underline{R}}ibosome$ ${\underline{A}}ffinity$ ${\underline{P}}urification$) for rice. These technologies enable us to follow dynamics in chromatin, nuclear pre-mRNAs and ribosome-bound mRNAs in meristems and diverse cell types. With these technologies we can better interpret responses to stresses and reestablishment of homeostasis. These include stress acclimation strategies involving changes in metabolism and development, such as dynamics in suberin deposition in sub-epidermal layers of roots that limit water loss under drought and oxygen escape during waterlogging. Our new data uncover dynamic and reversible regulation at multiple levels of gene regulation and provide new insights into processes of stress resilience. Supported by US NSF-PGRP Plasticity (IOS-1238243), Secretome (IOS-1546879) and REU (DBI-146129) grants.

• Applied Biological Chemistry
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• 제42권1호
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• pp.34-38
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• 1999

토마토의 genome내에는 적어도 5개 이상의 PAL유전자 좌가 존재한다는 사실을 이 등(1992)이 이미 genomic Southern blot hybridization으로 확인하여 보고하였다. 그러나 본 연구에서 제작한 genomic DNA libraries를 대상으로 검색한 결과 기존에 보고된 PAL유전자 이외에 약 15 kb 와 10 kb에 해당하는 큰 EcoRI 단편을 확보 할 수 있었다. 이들 단편을 BamHI, HindIII등 9종의 제한효소를 사용하여 Southern blot hybridization을 행한 결과 PAL X1의 경우는 모든 효소에 대하여 2개의 단편이 hybridization 되었으며, 특히 BamHI으로 절단하여 얻은 3개의 단편중 두 개는 PAL5 유전자의 exon 2 부위에서 취한 oligomer(18 mer)와 primer extension 반응이 진행되어서 약 200 bp의 PAL유전자와 아주 높은 상동성을 갖는 염기서열이 확인되었다. 따라서 PAL X1유전자는 2 copy의 유전자가 나란히 존재하거나 아니면 염색체 재배열이 진행된 것으로 추정된다. 이러한 결과는 적어도 7개 이상의 PAL유전자 좌가 토마토 염색체내에 존재하는 것으로 사료된다.