• Horticultural Science & Technology
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• v.30 no.6
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• pp.626-634
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• 2012

There are variations among grapevine genotypes in the levels of tolerance to cold, and cold-hardiness of grapevine has been affected by the change of short-term environment during over-wintering. In this study, the responses of vines to cold in open field and rain-shelter system were investigated to obtain useful information in increasing the tolerance to cold in grape cultivation. Total carbohydrate content of bearing mother branches was higher in the rain-shelter system than in the open field, and lower in the branches of 'Muscat Bailey A' than in 'Campbell Early' and 'Kyoho'. Bud-burst and shoot growth were better in the rain-shelter system than in open field, whereas there is no significant difference among the treatments of net beside vines. There was also low incidence of gray mold in rain shelter system. Stilbene compounds such as t-piceid, resveratrol, piceatannol, c-piceid were accumulated in the cold-treated shoot from vine cuts harvested in rain shelter system. Genes of chalcone isomerase, manganese superoxide dismutase, proline rich protein 2, and temperature induced lipocalin were highly expressed in the cold-treated shoot from vine cuts harvested in rain shelter system. While there was not change of air temperature, but high reduction of wind speed in the rain shelter system compared to open field, and increase in the reduction of wind speed by net treatment. The damage of grapevines by cold in the extreme low temperature could be reduced by keeping them in the rain shelter system with net during winter season.

• Journal of Plant Biotechnology
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• v.35 no.4
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• pp.281-290
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• 2008

In plant, Receptor-like kinases (RLKs) are protein family, though its function is not yet understood, consisted of a predicted signal sequence, single transmembrane region, and cytoplasmic kinase domain. RLKs are involved in hormonal response pathways, cell differentiation, plant growth and development, self-incompatibility, and symbiont and pathogen recognition. In this study, expression levels of RLG1, RLG5, RLG6, RLG#6, RLG8, RLG10, RLG17, RLG18 and RLG20 were analyzed by Real-time PCR, when rice (Oryzae sativa) was treated abiotic stress. The expression levels of all RLGs were compared each other by analyzed value of threshold cycles ($C_T$). Consequently, RLGs were suppressed by NaCl as salinity stress, and expression of each RLK genes were showed difference treated salicylic acid and wound, respectively. However, All RLGs were induced under low temperature condition. Therefore, our results indicate protection-function of RLK genes to be an early response of rice against cold weather.

• Journal of Ginseng Research
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• v.32 no.4
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• pp.300-304
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• 2008

Cysteine proteinases play an essential role in plant growth and development but also in senescence and programmed cell death. They participate in both anabolic and catabolic processes. In addition, they are involved in signalling pathways and in the response to biotic and abiotic stresses. A cDNA clone encoding cysteine proteinase (CP) gene, designated PgCysP1, was isolated from Panax ginseng C. A. Meyer. Reverse transcriptase (RT)-PCR results showed that PgCysP1 expressed at different level in P. ginseng hairy root. Different stresses such as biotic as well as abiotic stresses triggered a significant induction of PgCysP1. The positive responses of PgCysP1 to the various stimuli suggested that PgCysP1 may help to protect the plant against reactive environmental stresses.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.4
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• pp.31-37
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• 2000

In the case of metal-induced lateral crystallization (MILC) for low temperature poly-Si TFT, offset length between Ni-thin film and the sides of gate could be modified to control the location of MILC boundary. Electrical characteristics were compared to analyze the effect of MILC boundary that was located either in or out of the channel region of the TFT. By removing the MILC boundary from channel region, on current, subthreshold slope and leakage current properties could be improved. When MILC boundary was located in the channel region, leakage current was reduced with electrical stress biasing. The amount of reduction increased as the channel width increased, but it was independent of the channel length.

• The Korean Journal of Ecology
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• v.19 no.2
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• pp.151-163
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• 1996

To investigate the early symptoms of light-chilling, alterations of chlorophyll fluorescence transients were monitored in cucumber (Cucumis sativus L. cv. Ilmichungjang) leaves. During 24 h chilling, decreases in (Fv)m/Fm, qE and qQ, and an increase in Fo were observed. The chilling effects were not recovered at room temperature, and a significant increase in Fo was observed during the recovery period. After 6 h chilling, ‘dip’(D) level of the transients became obscure, and the negative slope after ‘peak’(P) disappeared. The first derivative (dFv/dt) of the fast fluorescence rise curve was used to obtain more accurate information about the changes in the transients. The maximal rate of the fluorescence increase in the D-p rise curve (Fr) has been the most frequently used chilling stress indicator. However, a correct value of Fr could not be measured when the D level became obscure. This problem was overcome by introducing a new indicator, HFr (dFv/dt at Fv = 1/2 (Fv)m), and HFr gave very similar values to Fr. To monitor the changes in curvature around D level, another new parameter, ${\Delta}S$(D-Fr), was also introduced. These three parameters decreased very sensitively during light-chilling. In addition, increases in these parameters were observed during the first 2 h chilling, but this increase in Fr was also observed in pea leaf discs dark-chilled for 15 min, suggesting that this very early change is a common response to chilling in both pea and cucumber leaves. Quenching coefficients were also very sensitive to chilling, especially qE. Discussion on the usage of these parameters as chilling stress indicators is given in the text.

• The Journal of Pediatrics of Korean Medicine
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• v.19 no.2
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• pp.215-228
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• 2005

Objective : The study was aimed to evaluate the anti-stress effect of KYT on the cold-stressed Mice. Methods: The experimental animals were stressed in cold room $(4{\pm}0.5^{\circ}C)$ for one hour in a day during two weeks, and administred 131mg/100g KYT extract for two weeks before stress. For two weeks, while the experiment was taking place, we conducted a research about the change of weight and content of norepinephrine, epinephrine, dopamine, cortisol and GOT, GPT in the mice serum. Results : KYT extract significantly inhibited the decrease of body weight induced by stress, compared with the control group. KYT extract had no significant decreasing effect on the change of content of the serum GOT but had significant decreasing effect on the change of content of the serum GPT compared with the control group. KYT extract had significant decreasing effect on the change of content of the serum cortisol compared with the control group. KYT extract had decreasing effect on the change of content of the serum dopamine compared with the control group. KYT extract had no decreasing effect on the change of content of the serum norepinephrine compared with the control group. KYT extract had significant decreasing effect on the change of content of the serum epinephrine compared with the control group. Conclusions : According to the above results, it is concluded that KYT will be useful as a preventive and remedy against stress disease.

• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.155-157
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• 2006

송전전압이 점차 초고압화되면서 절연체의 유전특성을 개선하여 송전용량을 향상시키고, 절연내력을 높여 케이블 외경을 저감시키려는 시도에 따라 우수한 유전특성 및 절연내력을 갖는 폴리머 절연층과 기계적 특성, 절연유와의 적합성이 우수한 크라프트지의 장점을 혼합시킨 반합성지가 개발되어 전력케이블의 주절연재료로 사용되고 있다. 본 논문은 LS전선이 국내최초로 개발한 400 kV급 반합성지 전력케이블 및 접속함 개발과정 및 이와 관련된 요소기술에 대해 기술하였다. 송전시스템에서 요구되는 유전특성의 반합성지를 설계 제작하여, 기존 크라프트 절연지 대비 유전손실은 50% 수준, 절연내력은 125%이상의 반합성지를 개발하였고, 반합성지 고유의 특성인 팽윤율을 조절하여 케이블을 제조하였다. 반합성지 절연 케이블에 필요한 접속함에서는 보강절연재로 케이블과 동일한 반합성지를 사용하여 전체적인 3기를 감소시키고, 열저항성을 줄이고자 노력하였다. 또한, 접속함 조립공정에 필요한 저온연공법을 개발하여 반합성지에 열적 스트레스를 최소화하였다. 상기 관련기술의 개발 결과로, IEC 60141, AEIC CS2-97 및 NGTS 3.5.1에 근거하여 400 kV급 반합성지 OF 케이블 및 접속함에 대해 국제 공인기관인 KEMA의부터 Type Test을 인증받았다.

• Korean Journal of Materials Research
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• v.5 no.6
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• pp.706-714
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• 1995

Silicon oxide thin films were deposited by remote plasma chemical vapor deposition (RPCYD). The effect of the operating variables, such as plasma power, deposition temperature and partial pressure of reactant on the material Properties of the silicon oxide film was investigated. By XPS, it was found out that the film was suboxide (O/Si<2) and small amount of nitrogen due to the plasma excitation was accumulated at the Si/SiO$_2$interface. The amount of dangling bonds at the Si/SiO$_2$interfaces were measured by ESR and the concentration of hydrogen bond was obtained by SIMS and FT-IR. The bond angle distribution(d$\theta$/$\theta$) was shown to be similiar to thermal oxide above 20$0^{\circ}C$ but the etch rate was higher than that of the thermal oxides due to the structural difference and the stress between silicon substrate and silicon oxide film.

• Korean Journal of Plant Resources
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• v.17 no.3
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• pp.239-247
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• 2004

A cyclophilin 1 cDNA clone(GenBank accession no.CF924191) was isolated from the taproot of C. lanceolata and designed as C1CyP1. Determination of the nucleotide sequence of C1CyPl identified an open reading frame of 525bp, which shared high homologies with cyclophilins that were previously reported in other organisms. The C1CyP1 amino acid sequence possesses 7 amino acid residue stretch(KSGKPLH) that is characteristic of plant cytosolic dehydrins. Currently available amino acid residues of plant cyclophilins were compared to examine their phylogenetic relationship to C1CyP1. In the phylogenetic analysis, based on the aligned sequences, C1CyP1 showed high homology with arabidopsis ROC2 and rice CyP1. The transcript that corresponded to C1CyP1 was abundant in callus, but only basal level of transcript was detected in stem, leaf and root. For the study in the defense mechanism against various stresses, we report expression patterns of this gene by quantative RT-PCR.

• Horticultural Science & Technology
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• v.29 no.6
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• pp.561-567
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• 2011

Cold tolerance of the native Rhododendron species which are on the verge of extinction in Korean nature were compared with the introduced species and its mechanism were studied physiologically with the investigation of the leaf angle, leaf curling, and photosynthetic activity. The degree of cold tolerance measured with the leaf burning after winter season was higher in the native species, Rhododendron brachycarpum and Rhododendron brachycarpum var. roseum than all the introduced species. 'Nova Zembla', an introduced species, showed high sensitivity to the low temperature. Changes in leaf angle by the low temperature were bigger in 2 native species and 'Parker's Pink' than the other introduced species and small comparatively in 'Nova Zembla' and 'Cunningham's White' cultivar. Leaf curling also occurred strongly in 2 native species by the low temperature. While, it was comparatively little and mild in the other introduced species. Therefore these results suggested that the leaf movement such as leaf angle change and curling adapted to the low temperature is positively related to the cold tolerance of 2 native species. By the way, such relationship is not explainable in the cold-sensitive 'Parker's Pink' cultivar showing comparatively stronger leaf movement. Photosynthetic activity measured before the winter season was high in the cold-tolerant R. brachycarpum and its recovery after winter season was faster in the 2 native species and the introduced 'Cynosure' cultivar than the other introduced species. They were the lowest in the most cold-sensitive 'Nova Zembla'. This phenomena occurred similarly even in the stomatal conductivity, suggesting that the movement of water from the roots to the leaves is better and then the leaf burning after winter season become small in the cold-tolerant species. The recovery of photosynthetic activity and stomatal conductivity was comparatively slower in the cold-sensitive 'Parker's Pink'. From the above results, leaf behavior adapted to the low temperature during the winter season and water movement to the leaves are related collectively to the cold tolerance represented as the leaf burning in the Rhododendron species is suggested.