• Journal of Microbiology
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• 제35권3호
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• pp.228-233
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• 1997

The MTF1 gene of Saccharomyces cerevisiae encodes a 43 kDa MITOCHONDRIAL RNA polymerase specificity factor which recognizes mitochondrial promoters to initiate correct transcription. To better understand structure-function of the MTF1 gene as well as the transcription mechanism of mitochondrial RNA polymerase, two cold-sensitive alleles of the MTF1 mutation were isolated by plasmid shuffling method after PCR-based random mutagenesis of the MTF1 gene. The mutation sites were analyzed by nucleotide sequencing. These cs phenotype mtf1 mutants were respiration competent on the nonfermentible glycerol medium at the permissive temperature, but incompetent at 13.deg.C. The cs phenotype allele of the MTF1, yJH147, encoded an L146P replacement. The other cs allele, yJH148, contained K179E and K214M double replacements. Mutations in both alleles were in a region of Mtflp which is located between domains with amino acid sequence similarities to conserved regions 2 and 3 of bacterial s factors.

• 한국생활과학회지
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• 제10권1호
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• pp.101-111
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• 2001

The purpose of this study was to investigate using and evaluative criteria for purchasing of sleepwear in winter. Subjects were 523 males and females aged from twenties to fifties, living in Chongju and Taejon. For data analysis, frequency, descriptive analysis, t-test, and F-test were used. The results are as follows. First, the ownership of sleepwear was sweat suits with zippered top, pajamas, T-shirts/pants, underwear, and nightgown in order. The mean of using sweat suits was used the highest, and subjects used more home wear than sleepwear in winter. Second, the using or sleepwear had a significant difference in cold-sensitiveness and body types. Cold-sensitive group used sweat suit and T-shirts/pants more than cold-insensitive group. Also, groups who are thin wore sweat suit the most while groups who are corpulent, used underwear the most when they slept. Third, subjects, who are married women and use bed, used nightgown, but pajamas were used by groups who are older, married, and professional. Sweat suits and T-shirts/pants were used the most by single aged twenties. Forth, consumers considered the wearing comfort when they purchased sleepwear for winter, and they evaluated washing/management, fabric, design/style, economic, service, brand, and others' response in order, for judging the quality of sleepwear. Also, the evaluative criteria had a significant difference in demographic variables such as sex, occupation, and marital state. These results implied that sleepwear would be needed for winter in terms of behavioral temperature regulation. Especially, cold-sensitive and thin group would wear knitted and two-piece sleepwear for thermal comfort when they sleep in winter. Also, Using and evaluative criteria of sleepwear would be different in demographic characteristics. For winter, sleepwear should be develop based on physiologic as well as demographic variables.

• 분석과학
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• 제12권1호
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• pp.75-79
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• 1999

봄무우 유식물의 자엽과 하배축에서 저온처리동안 변화하는 polyamine(PA)의 농도를 분석하고, PA이 저온 스트레스와 관련이 있는지를 분석하였다. 자엽에서 저온 스트레스동안 putrescine(PUT)의 농도가 증가되었고, 전반적으로 PUT와 spermidine(SPD) 농도의 변화가 심하였다. 따라서 PUT와 SPD는 저온 스트레스의 조건하에서 합성되거나 또는 유리된 것이다. 그러나 spermine(SPM)의 농도에는 거의 변화가 없었다. 하배축의 대조구에는 SPD만이 존재하고, 저온 스트레스를 주면, 유리된 PA의 농다가 증가되었고, 지속된 저온 스트레스동안 PA의 농도가 급속히 감소되었다. 하배축은 일반적으로 저온처리에 매우 예민성을 나타내는 것으로보아, 자엽과 비교해서 세포내에 PA의 농도가 낮기 때문인 것으로 판단된다. 자엽에서 PUT과 SPD가 저온 스트레스의 저항력에 관여하고, 하배축에서는 PA이 저온 스트레스에 대한 저항력의 증대와 아무 관련이 없는 것으로 사료된다. 이상의 결과로 PUT와 SPD는 저온 스트레스에 대항하여 저항력을 증대시키는 것으로 판단된다.

• 한국육종학회지
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• 제43권1호
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• pp.1-13
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• 2011

Low temperature stress is one of the major negative factors affecting vegetative and reproductive growth of rice. To better understand responses of rice plants to low temperature we analyzed transcriptome expression patterns in glumous flower of cold-tolerant japonica rice variety, Stejaree45, and cold-susceptible variety, HR19621-AC6 at booting stage under cold water irrigation. A total of 2,411 probes were differentially expressed by low temperature in glumous flowers of the two varieties. Some important genes involved in hormone biosynthesis showed variety-specific regulation. Expression of GA20ox3 and GA2ox, among the genes involved in GA biosynthesis, was regulated differentially in the two varieties. Among the genes involved in IAA biosynthesis, YUCCA1 and TAA1:1 showed variety-specific regulation. Among the genes involved in cytokinin biosynthsis and signaling, expression of LOG, HK1 and HK3 was significantly down-regulated only in the cold-susceptible variety. Among the genes involved in ABA biosynthesis, NSY and AAO3 were down-regulated only in the cold-tolerant variety. In general, genes involved in GA, IAA and cytokinin biosynthesis responded to cold temperature in such a way that capacity of those bioactive hormones is maintained at relatively higher levels under cold temperature in the cold-tolerant variety, which can help minimize cold stress imposed to developing reproductive organs in the cold-tolerant variety.

• Restorative Dentistry and Endodontics
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• 제12권1호
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• pp.149-153
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• 1986

Clinical analysis on early evidence of the pulp response to composite resin filling (27 cases) was made and reached to the results as follow; 1. Under age 40's early symptome was reported within the 1st, 2nd, 3rd and 4th week after composite filling evenly and age 50's reported after 4th week. 2. Sensitive response to cold were 11 cases, to warm 3 cases and to both (cold, warm) were 9 cases. 3. Tenderness to percussion and light pressure on apical area were 5 cases.

• 원예과학기술지
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• 제32권5호
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• pp.607-613
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• 2014

Calcium has been associated with improved cold tolerance in many crops. The aim of this study was to investigate the changes in leaf cell $Ca^{2+}$ distribution and cell organelle ultrastructure of loquat (Eriobotrya japonica Lindl.) plants in response to cold stress at $-3^{\circ}C$, using transmission electron microscopy (TEM). Two loquat accessions, Zaozhong 6 (a commercial cultivar) and oakleaf loquat (a wild relative) were used. Cold tolerance, as measured by leaf browning rate, was higher in oakleaf plants, and calcium treatment improved cold tolerance in both species. Cold stress first induced inward transport of $Ca^{2+}$ from the intracellular space. Then, the imported $Ca^{2+}$ was aggregated around the chloroplast membrane, finally entering the chloroplast. This pattern of $Ca^{2+}$ distribution in leaf cells occurred earlier in Zaozhong 6 than in the wild loquat. With increasing time of cold exposure, the chloroplast membranes of Zaozhong 6 leaves were damaged, blurred and even disappeared, while those of wild oakleaf loquat leaves maintained their structure longer. In Zaozhong 6, cold stress induced a clear cavity between poorly structured granal thylakoids and vesicles appearing inside the chloroplast, while in oakleaf leaves cold stress had little effect on the ultrastructure of chloroplasts (although chloroplast membranes looked blurred). Loquat leaves accumulated free calcium ions around chloroplasts in response to cold stress, with earlier calcium accumulation occurring in the cold-sensitive cultivar Zaozhong 6 than in wild oakleaf loquat. These results demonstrate that these two loquat species have differences in both cold tolerance and calcium accumulation dynamics.

• 한국의류산업학회지
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• 제20권6호
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• pp.744-751
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• 2018

This study aimed to provide the information on the thermal sensation and the amount of clothing worn of junior high school students in winter classroom the relation with their climate adaptability. Total usable questionnaires were obtained from 467 male and female students. The questionnaire included general characteristics, physical characteristics, self awareness of body shape, climate adaptability and subjective thermal sensation in winter classroom. The data were analyzed using SPSS Statistics 18.0 for frequency analysis, factor analysis, chi-square analysis, t-test and correlation analysis. The results were as follows. The average body type based on BMI was normal($20.1kg/m^2$ ). Females perceived their body type as thinner than males. They wore more (8.67 garment items compared to 8.14 for males). Only about 25% of students voted the thermal sensation to neutral(47% cool~very cold, 28% warm~very hot). Females were more sensitive to the cold, perceived less healthy, and wore more garments in the cold. Students felt colder in winter classroom when their cold adaptability was lower and they actively adjusted thermal insulation against the cold. It is recommended to suggest the guidelines for the proper indoor temperature and for the wear behavior in classroom in the perspectives of increasing the learning efficiency and improving the students' climate adaptability.

• 한국작물학회지
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• 제34권s02호
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• pp.96-114
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• 1989

There are several meterorolgical stresses in the winter cereal crops. Among these stresses, cold injury is one of the most important stresses for wheat and barley production in Korea. The reduction in grain yield of the wheat and barley due to cold injury has occurred almost every year in Korea. The objective of the study was to get the basic information in relation to the cold injury and to detect the method minimizing the damage of cold injury. When the air temperature was the ranges of -13$^{\circ}C$ to -15$^{\circ}C$, the soil temperature at the crown part of the plant was very stable, whereas in the ranges of -2$^{\circ}C$ to -3$^{\circ}C$ the soil surface temperature was more unstable and cold than air and subterranean temperatures. The different parts of the plant in wheat and barley possess the different levels of cold hardiness. In comparison to the cold hardiness of plant parts, the leaf and crown are the less sensitive to cold injury than root and vascular transitional zone. The type and extent of stress is determined by the redistribution pattern of water during freezing. These types from freezing processes were three types: a) Equilibrium freezing pattern b) Non -equilibrium freezing pattern, c) Non-equilibrium freezing pattern typical of tender tissues. Cold hardiness in wheat plants were more harder than barley plants at vegitative stage, but inverted at the reproductive stage. Injuries by low temperature during the seasons of barley cultivation in Korea were occured mainly in four stage; in the first and third stage, frost injury occurs, the second stage, freezing injury, and the fourth stage, chilling injury.

• 정보보호학회논문지
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• 제26권2호
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• pp.327-334
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• 2016

일반적으로 알려진 믿음과는 달리 다양한 컴퓨팅 장치의 메인 메모리로 사용되는 DRAM은 전원이 차단되더라도 저장하고 있던 데이터가 곧바로 사라지지 않고, 대신 어느 정도의 시간 동안 데이터를 유지하게 된다. 특히 DRAM을 냉각시키면 그 데이터 유지 시간이 더 길어진다는 사실 역시 알려져 있다. Cold Boot Attack이란 이러한 DRAM의 데이터 유지 성질을 이용하여, 전원이 차단된 DRAM으로부터 암호 알고리즘의 키와 같은 민감한 정보를 복구해내는 부채널 공격 방법의 일종이다. 본 논문에서는 대칭붕괴모델을 가정한 Cold Boot Attack 방법을 이용하여 전원이 차단된 DRAM으로부터 추출된 AES 키 비트열로부터 원래의 AES 키를 복구하는 알고리즘을 제안한다. 제안된 알고리즘은 추출된 AES 키 비트열의 랜덤성을 테스트하는 방법을 사용하여 후보 키 공간의 크기를 줄이는 방법을 사용한다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1539-1542
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• 2008

Plasma is 4th state of matters, which consists of electrons, neutral, and ionized particles. In biomedical research, cold plasma, which is generated in atmospheric condition, has been applied to disinfect microorganisms such as bacteria and yeast cells. Because of its low temperature condition, the heat-sensitive medical device can be easily sterilized by the cold plasma treatment. In recent years, the effects of plasma on mammalian cells have arisen as a new issue. Generally, plasma induces intensity dependent necrotic cell death. In this research, we investigate the feasibility of cold plasma treatment for cancer therapy by conducting comparative study of plasma effects on normal and cancer cells. We use THLE-2 (human liver normal cell) and SK-Hep1 (human liver metathetic cancer cell) as our target cells. The needle type of cold plasma is generated by the Helium plasma device. Two types of cells have different onset plasma conditions for the necrosis, which may be explained by difference in electrical properties of these two cell types.