• 제목/요약/키워드: temperature tolerance

검색결과 662건 처리시간 0.023초

Genetic Variation in Early Survival of Chum Salmon Families with Respect to Seawater Temperature

  • Choe Mi-Kyung;Yeo In-Kyu
    • Fisheries and Aquatic Sciences
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    • 제3권2호
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    • pp.88-96
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    • 2000
  • The present study estimated the variation of early survival of chum salmon families with respect to temperature and size after transfer to seawater. Heritability for seawater tolerance of half-sib families was also estimated at 45 days after hatching. Gametes were collected from 6 male and 18 female chum salmon to make 18 paternal half-sib families. Seawater tests were carried out at 3, 7 and $12^{\circ}C$ of $32\%$ seawater and compared with freshwater. Survival was significantly affected by seawater temperature. The highest seawater tolerance was obtained in 45-day old chum salmon at $7^{\circ}C$ seawater and the lowest seawater tolerance was obtained at $3^{\circ}C$. Overall survivals in seawater tolerance at $32\%$ varied among families. There were significant variance in fry survival among females (P=0.0001), and among males (P=0.0001). The heritabilities of survival in seawater in chum salmon were estimated to be 0.32-0.34 for the sire components at 45 days after hatching in 1998.

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알콜발효에서 효모의 에탄올 내성 조건-발효온도와 기질종류에 대한 연구 (The Conditions Affecting Ethanol Tolerance of Yeast strains in Alcohol Fermantation - Study on the Fermantation Temperature and Substrate Type)

  • 김형진;유연우
    • KSBB Journal
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    • 제4권2호
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    • pp.167-171
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    • 1989
  • Glucose와 lactose를 이용한 알콜발효에서 Sacchar-omyces cerevisine STV89와 Kluyveromyces fragilis CBS397의 에탄올 내성에 대한 발효온도의 영향에 관한 연구를 수행하였다. 최대 비성장 속도와 에탄올 생성 속도는 발효온도에 따라 35$^{\circ}C$까지 증가하였으나 최대 cell 농도와 에탄올 농도는 발효온도 증가에 따라 감소하였다. Cell viability도 역시 발효온도가 낮을수록 향상되었다. 따라서 수행한 실험조건에서 효모의 에탄올 내성은 $25^{\circ}C$에서 가장 우수하였다. 균주의 비교에서 에탄올에 대한 내성이 S. cerevisiae가 K.fragilis보다 동일한 실험조건에서는 더 우수하였으며, 탄소원의 종류에 대한 비교에서 K. fragilis의 에탄올에 할 때보다 더 우수하였다.

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에너지대사의 계절변동과 내한내열성으로 본 한국농업인의 환경적응 능력 (The Adaptability of Korean Farmers to Environment by the Seasonal Fluctuation of Energy Expenditure, Cold and Heat Tolerance)

  • 최정화;황경숙
    • 한국지역사회생활과학회지
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    • 제17권2호
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    • pp.49-60
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    • 2006
  • It was measured the energy expenditure in each season, the cold tolerance in winter and the heat tolerance in summer. Farmers' adaptability to the change of environment was compared with those of city-dwellers such as indoor workers and street cleaners to determine the effect of living environment, especially living temperature, on the health of human body. It turned out that farmers had experienced wide range of temperature that was higher in summer and lower in winter than indoor workers. Farmers and street cleaners showed seasonal adaptation in energy expenditure, which was high in winter and low in summer. However, indoor workers did not show seasonal changes. Energy expenditure had an inverse correlation with the temperature in work place where subjects spend the longer time in a day except in female indoor workers in Seoul. And It was proved that farmers and street cleaners had stronger cold tolerance and heat tolerance than indoor workers.

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군 무기체계에 적용되는 4 축 스트레인-게이지의 오차에 대한 신호처리 소프트웨어 기법 (A Signal Processing Software Technique for the Tolerance of the 4 Axis Strain-gauge Sensors applied to the Military Weapon System)

  • 이영준;이종호
    • 한국전자통신학회논문지
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    • 제18권1호
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    • pp.185-194
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    • 2023
  • 군 무기체계에 널리 적용되는 4축 스트레인 게이지는 열악한 온도와 진동조건에서 운용되기 때문에 오차가 커지게 되고, 오동작을 일으킬 수 있다. 이를 개선하기 위해 본 논문에서는 군 무기체계에 적용되는 4축 스트레인 게이지의 오차에 대한 신호처리 소프트웨어 기법을 제안한다. 첫째, 주위 온도에 따른 스트레인-게이지의 오차와 신호처리회로의 오차를 평가하고 분석하였고, 둘째, 스트레인-게이지의 오차를 개선할 수 있는 불감대 영역과 오프셋 영역의 처리에 대한 소프트웨어 기법을 제안한다. 소프트웨어 기법을 적용한 실험결과는 온도시험과 운용시험에서 정상적으로 동작하는 것을 확인하였다. 따라서, 제안한 소프트웨어 기법은 타당하므로, 스트레인-게이지를 사용하여 시스템을 설계할 때 주위 온도와 진동에 따른 오차 개선에 유용한 정보로 사용될 수 있다.

정기적인 찜질방노출이 청년과 노년 여성의 내한성에 미치는 영향 (The Effects of Regular Jjimjilbang Exposure on Cold Tolerance in Young and Elderly Females)

  • 최정화;송은영;황수경
    • 한국지역사회생활과학회지
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    • 제18권4호
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    • pp.599-607
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    • 2007
  • We analyzed the effects of regular Jjimjilbang (Korean sauna) exposure on the cold tolerance in young and elderly females. Subjects were young (n=7) and elderly (n=7) females who had never had Jjimjilbang exposure experience. The Jjimjil training group was exposured in the Jjimjilbang 19 times per week. Jjimjibang exposure was limited to three times per day. Jjimjil activity was taken freely. To prove the effects of the cold tolerance, subjects were exposed to cold air ($12{\pm}1^{\circ}C,\;60{\pm}10%$RH). In these conditions, subjects were exposed for 30 minutes at which time rectal temperature, skin temperatures, clothing microclimate, energy expenditure, blood pressure and subjective sensation were measured. To prove the effects of the local cold tolerance, vascular hunting reaction was observed measuring the finger skin temperature while the left middle finger tip was immersed in cold water of $0^{\circ}C$ for 30 minutes. The results are as follows. According to repeated Jjimjil exposure, rectal temperature changes, peripheral temperature and energy expenditure were increased gradually in the cold climate chamber. Blood pressure, subjective sensation and vascular hunting reactions did not show any significant difference. In conclusion, regular Jjimjilbang exposure has negative effects on the ability of the body to improve its regulation of temperature especially in cold tolerance.

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혈압 관리를 위한 4주간의 착의훈련이 고혈압 전단계자의 내열성에 미치는 영향 (Effects of a Four-week Clothing Program for Improving Vascular Compliance on Heat Tolerance)

  • 최정화;박준희
    • 한국지역사회생활과학회지
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    • 제22권3호
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    • pp.445-454
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    • 2011
  • This study was performed on 5 prehypertensive male participants to investigate the effects of the clothing program for improving the vascular compliance on heat tolerance. The clothing program means the alternate stimulation of the temperature using clothes. The participants wore two different garments with $1.5^{\circ}C$ difference in the temperature inside clothing in a climatic chamber ($18.8{\pm}0.2^{\circ}C$, $38{\pm}3%RH$) alternately for 4 weeks. Heat tolerance tests were conducted in the climatic chamber of $35.2{\pm}0.5^{\circ}C$, $54{\pm}3%RH$ before and after the clothing program. The results were as follows. The $\overline{T}$sk, Tr and heart rate were lower in the post test than in the pre test (p<.01). The whole body and local sweat rates as well as systolic and diastolic blood pressures had reduced the tendencies in the post test. Participants felt less wet and more comfortable in the post test than in the pre test(p<.01). These results showed that the clothing program through the alternate stimulation of the temperature positively affected the improvement of heat tolerance.

Effect of Salicylic Acid on Growth and Chilling Tolerance of Cucumber Seedlings

  • Lee, Gui-Soon;Hong, Jung-Hee
    • 한국환경과학회지
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    • 제11권11호
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    • pp.1173-1181
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    • 2002
  • The present study was undertaken to investigate the effect of low temperature and salicylic acid(SA) on the chilling tolerance of acclimated and nonacclimated cucumber(Cucurmis sativus L.) seedlings. The acclimation phenomenon was characterized in chilling-sensitive cucumber seedlings and found to have a significant effect on the survival and shoot dry weights. The injuries experienced by the acclimated seedlings in the third leaf stage were on average smaller by half than those experienced by the nonacclimated seedlings. Chilling also caused a large increase in the free proline levels, regardless of the acclimation status. Exogenous treatment with SA(0.5mM) resulted in improved growth and survival of the nonacclimated chilled seedlings, indicating that SA induced chilling tolerance and SA and acclimation had common effects. The application of cycloheximide in the presence of SA restored the acclimation-induced chilling tolerance. The elevated proline level observed in the cold-treated and SA-treated plants was more pronounced in the light than in the dark at a chilled temperature, indicating that endogenous proline may play a role in chilling tolerance by stabilizing the water status in response to chilling. From these results it is suggested that SA provided protection against low-temperature stress by increasing the proline accumulation, and pre-treatment with SA may induce antioxidant enzymes leading to increased chilling tolerance.

Effects of low temperature and salicylic acid on chilling tolerance in cucumber seedlings

  • Jung, Sang-Duck;Jung, You-Jin;Kim, Tae-Yun;Hong, Jung-Hee
    • 한국환경과학회:학술대회논문집
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    • 한국환경과학회 2002년도 봄 학술발표대회 발표논문집
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    • pp.468-471
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    • 2002
  • The present study was undertaken to Investigate the effects of low temperature and salicylic acid (SA) on chilling tolerance In acclimated and nonacclimated cucumber seedlings. Acclimation significantly affected survival and shoot dry weights. Injuries of acclimated seedlings at the third leaf stage were on the average smaller by half than those of the nonacclimated ones. Chilling caused a large increase in free proline levels, regardless of acclimation status. Exogenous treatment with SA resulted in improvement in growth and survival of acclimated, chilled seedlings, indicating SA and acclimation have common effects. Cycloheximide treatment In the presence of SA restored acclimation-induced chilling tolerance. An elevated proline level was observed in cold-treated and SA- treated plants and the level was more pronounced in the light than in the dark at chilled temperature, indicating that endogenous proline may play a role in chilling tolerance.

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Hybridization에 의한 반수체 재조합 효모균주의 전분 발효능 증진

  • 박선영;김근;이창후
    • 한국미생물·생명공학회지
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    • 제24권6호
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    • pp.726-732
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    • 1996
  • To improve the fermentation characteristics(such as starch-degradability, ethanol tolerance, sugar and high-temperature tolerance) of recombinant haploid yeast Saccharomyces diastaticus K114, hybridization technique was used. The hybridization partner was S. diastaticus 1177 which had good glucoamylase activity and fermentabi- lity. The best hybrid HH64 showed improved ethanol tolerance, sugar and high-temperature tolerance. Especia- lly, the starch-fermentability was significantly improved, since the hybrid produced 1.60% (w/v) ethanol from 4% (w/v) starch, while the recombinant haploid K114 produced 1.30% (w/v) ethanol. The optimum temperature and pH for the starch-fermentation by the hybrid HH64 was 30$\circ$C and 5, respectively. The hybrid yeast HH64 produced 7.5% (w/v) ethanol directly from 20% (w/v) starch.

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여름철 내열성 증진을 위한 정량적 착의훈련의 효과 (제2보) -20대 여성의 의복내 온도를 지침으로- (Quantitative Wear Training for the Improvement of Heat Tolerance in Summer (Part II) -Wear Training by Optimal Temperature Inside Clothing for Women in Their 20s-)

  • 이효현;최정화
    • 한국의류학회지
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    • 제36권4호
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    • pp.371-381
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    • 2012
  • This study investigates quantitative wear training effects and involved 15 participants from a previous study (part 1) in May to September 2009. Before wear training, the subjects' rectal temperature, skin temperature, heart rate, blood pressure and local sweating were measured for 1 hour in a climate chamber ($39{\pm}1^{\circ}C$, $65{\pm}5%RH$, 0.3m/s) to evaluate heat tolerance. Subsequently, the subjects were divided into 3 groups that consisted of 5 participants. Group N (control-group) dressed the participants so that they felt comfortable (or cool). Group W and MW where participants underwent regular wear training for 10 weeks (5 days a week a total of 50 times). The intensity of the wear training for the participants of group MW was stronger than that for group W. A heat-tolerance experiment was performed after wear training. The results were as follows: 1. The participants of groups W and MW felt more comfortable after wear training than before wear training in the case of warmer $T_{cl}$. However, no significant differences were observed before and after wear training for group N. 2. The heat tolerance of the participants of groups W and MW was higher after wear training than before wear training. However, no significant difference was noted in this regard for group N. 3. The results showed the wear training effect (based on quantitative guidelines). The results show that the predicted optimal temperature inside clothing can enhance heat tolerance.