• The Korean Journal of Physiology
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• v.3 no.1
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• pp.59-66
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• 1969

Experiments on thermoregulatory responses to cold immersion stimulus were carried out in September, 1968 (summer studies) and February, 1969 (winter studies). Eight each of ama and control subject were selected at random from a same community in Yong-Do Island, Pusan. The results obtained are summarized as follows: 1) The rate of fall in muscle temperature of forearm during a 30 min-immersion in $6^{\circ}C$ water bath was significantly slower in the ama in winter and was about the same in the two groups in summer. However, the magnitude of change in the skin temperature and the heat fluxes observed during immersion period was not significantly different either between groups or between seasons. 2) Both finger blood flow and skin temperature during one hr-immersion in $6^{\circ}C$ water bath decreased significantly in the ama as compared to the control. The magnitude of cold-induced vasodilatation during immersion period was significantly greater in the control in winter. However, the time of onset and blood flow at onset showed no significant relation between groups. 3) The magnitude of reactive hyperemia after a 5 min-arterial occlusion in both air and $15^{\circ}C$ water bath was significantly lower in the ana than in the control. In control subjects, post-occluded blood flow in water was significantly greater than in air, while in the ama it decreased to 1/2 of control values. The time required for the return of blood flow to resting values in the air was faster in the ama than in the control but was the same in water in the two groups. 4) The results suggest that vasoconstrictor tone increased in the ama in winter, indicating the development of vascular adaptation as a part of cold acclimatization.

• Korean Journal of Agricultural and Forest Meteorology
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• v.10 no.3
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• pp.94-101
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• 2008

Warming trends during winter seasons in East Asian regions are expected to accelerate in the future according to the climate projection by the Inter-governmental Panel on Climate Change (IPCC). Warmer winters may affect short-term cold hardiness of deciduous fruit trees, and yet phenological observations are scant compared to long-term climate records in the regions. Dormancy depth, which can be estimated by daily temperature, is expected to serve as a reasonable proxy for physiological tolerance of flowering buds to low temperature in winter. In order to delineate the geographical pattern of short-term cold hardiness in grapevines, a selected dormancy depth model was parameterized for "Campbell Early", the major cultivar in South Korea. Gridded data sets of daily maximum and minimum temperature with a 270m cell spacing ("High Definition Digital Temperature Map", HDDTM) were prepared for the current climatological normal year (1971-2000) based on observations at the 56 Korea Meteorological Administration (KMA) stations and a geospatial interpolation scheme for correcting land surface effects (e.g., land use, topography, and site elevation). To generate relevant datasets for climatological normal years in the future, we combined a 25km-resolution, 2011-2100 temperature projection dataset covering South Korea (under the auspices of the IPCC-SRES A2 scenario) with the 1971-2000 HD-DTM. The dormancy depth model was run with the gridded datasets to estimate geographical pattern of change in the cold-hardiness period (the number of days between endo- and forced dormancy release) across South Korea for the normal years (1971-2000, 2011-2040, 2041-2070, and 2071-2100). Results showed that the cold-hardiness zone with 60 days or longer cold-tolerant period would diminish from 58% of the total land area of South Korea in 1971-2000 to 40% in 2011-2040, 14% in 2041-2070, and less than 3% in 2071-2100. This method can be applied to other deciduous fruit trees for delineating geographical shift of cold-hardiness zone under the projected climate change in the future, thereby providing valuable information for adaptation strategy in fruit industry.

• Proceedings of the ESK Conference
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• 1997.04a
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• pp.227-246
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• 1997

With a view of to providing basic data for designing male's and female's clothes, heslthy males and females(five each) were exposed to three different environmental temperature( $20{\pm}1.0^{\circ}C$ $28{\pm}1.0^{\circ}C$,$32{\pm}1.0^{\circ}C$ in the nude. Their adaptation of skin temperature, physilogical responses, oral temperature, blood pressure, pulse rates) and psychological reactions (thermal, comfort and perceptive sweat sensations) were analyzed to be as follows; The subjects's skin temperature had a similar look of adaptation, but the stability of skin temperature differed at the $20{\pm}1.0^{\circ}C$and at the $28{\pm}1.0^{\circ}C$ Males had higher skin temperatures at three environmental temperatures, but females showed a higher temperature change at the $20{\pm}1.0^{\circ}C$ and$28{\pm}1.0^{\circ}C$ and males at the $32{\pm}1.0^{\circ}C$ Thus females were more resistant to the cold, while male were more resistant to the heat. As environmental temperature increased, oral temperature and pulse rates also grew up. Females turned higher in oral temperature and lower in blood pressure, but both sexes had a normal range of physiological reactions. Even though three environmental temperature were same changes in thermal sensation at and in perceptive sweat sensation at $28{\pm}1.0^{\circ}C$and in perceptive sweat sensation at$32{\pm}1.0^{\circ}C$ the two sexes had the same response in comfort sensation at the three environmental temperature.

• Journal of the Ergonomics Society of Korea
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• v.16 no.2
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• pp.39-59
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• 1997

With a view to providing basic data for designing male's and female's clothes, healthy males and females(five each) were exposed to three different environmental temperature($20{\pm}1.0^{\circ}C$, $28{\pm}1.0^{\circ}C$, $32{\pm}1.0^{\circ}C$) in the nude. Their adaptation of skin temperature, physiological responses( rectal temperature, blood pressure, pulse rates) and psychological reactions(thermal, comfort and perceptive sweaty sensations) were analyzed as follows; The subjects's skin temperature had a similar look of adaptation, but the stability of skin temperature differed at tha $20{\pm}1.0^{\circ}C$ and at the $28{\pm}1.0^{\circ}C$ Males had higher skin temperature at three environmental temperatures, but females showed a higher temperature change at the $20{\pm}1.0^{\circ}C$ and $28{\pm}1.0^{\circ}C$ and males at the$32{\pm}1.0^{\circ}C$ Thus females were more resistant to the cold, while males were more resistant to the heat. As environmental temperature increased, rectal temperature and pulse rates also grew up. Females turned higher in rectal temperature and lower in blood pressure, but both sexes had a normal range of physiological reactions. Even though three environmental temperatures were same changes in thermal sensation at $28{\pm}1.0^{\circ}C$and in perceptive sweat sensation at $32{\pm}1.0^{\circ}C$, two sexes had the same response in comfort sensation at the three environmental temperatures.

• Journal of Ginseng Culture
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• v.3
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• pp.1-10
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• 2021

Panax ginseng (Ginseng or Korean ginseng) is one of the most important medicinal herbs in the world. We made a high-quality whole genome sequence of P. ginseng using 'Chunpoong' cultivar, which is the first cultivar registered in Korea Seed and Variety Service (KSVS) with relatively similar genotypes and superior phenotypes, representing approximately 3 Gbp and 60,000 genes. Genome sequence analyses of P. ginseng and related speciesrevealed the origin of Korean ginseng and the ecological adaptation of 18 Panax species around the world. Korean ginseng and American ginseng (P. quinquefolius) are tetraploid species having 24 chromosome pairs, while the other 16 species are diploid species with 12 chromosome pairs. Panax and Aralia are the closest genera belonging to the Araliaceae family that diverged approximately 8 million years ago (MYA). All Panax species evolved as shade plants adapting to cool climates and low light conditions under the canopy of deep forests from Southeast Asia such as Vietnam to Northeast Asia such as Russia approximately 6 MYA. However, through recurrent ice ages and global warming, most diploid Panax species disappeared due to the freezing winter, while tetraploid P. ginseng may have appeared by allotetraploidization, which contributed to the adaptation to cold temperaturesin Northeast Asian countries including the Korea peninsula approximately 2 MYA. American ginseng evolved by the adaptation of P. ginseng in Northeast America after the intercontinental migration 1 MYA. Meanwhile, most of diploid Panax species survived in high-altitude mountains over 1,600 meters in Southeast Asia because they could not endure the hot temperature and freezing cold. The genome sequence provides good basisto unveil the origin and evolution of ginseng and also supports practical gene chips which is useful for breeding and the ginseng industry.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.1
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• pp.76-81
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• 2009

A nonlinear pressure controller to actively regulate the thrust of a solid propulsion system is presented. To compensate for the parametric uncertainties with respect to the chamber pressure induced by changing nozzle throat area, Lyapunov-based parameter adaptation method has been applied. In order to verify the effectiveness of the proposed control method, the experiments were carried out using the cold gas test equipment that can simulate the operating environment of variable thrust solid propulsion system. The experiment results show that the nonlinear pressure controller has better performance than conventional P and PI controller.

• Journal of Korean Society of Steel Construction
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• v.14 no.5 s.60
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• pp.665-674
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• 2002

The back-to-back and box-shaped headers used in light gauge steel structures have some disadvantages, i.e., construction efficiency and cost competitiveness. As such, cold-formed steel L-shaped headers have been developed and are used actively in advanced nations. However, this system has not been used in Korea because of inadequate investigation and adaptation efforts and lack of application example. Thus, this research evaluated the structural performance of L-header using buckling analyses and bending tests. Test results were compared using the AISI design criteria. Test results showed that local buckling and distortional buckling governed buckling behavior in gravity loads and uplift loads, respectively. These results were consistent with the calculated nomial strengths using the AISI design criteria.

• Korean Journal of Plant Tissue Culture
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• v.21 no.1
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• pp.15-22
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• 1994

To understand the molecular mechanism of hardening process in somatic embryo development and artificial seed germination in celery (Apium graveolens L.), the changes of protein synthesis by ABA or cold teatment at early globular stage were examined. Protein content and nitrate reductase activity in ABA- or cold-treated somatic embryo and seedlings were higher than that in unheated ones. The protein content and nitrate reductase activity were more prominent in somatic embryos than in seedlings. From two-dimensional electrophoresis, several protein spots specific to ABA or cold treatment were identified: 30 KD, 32 KD, 171 KD and 205 KD at heart-shaped stage; and 29 KD, 33 KD, 37 KD, 38 KD, 41 KD, 55 KD, 66 KD, and 110 KD at cotyledonary stage were the most specifically synthesized However the synthesis of certain polypeptides were repressed at heart-shaped or cotyledonary stage: 42 KD, 44 KD, 59 KD, 64 KD, 101 KD, 104 KD, and 190 KD at heart-shaped stage; and 29 KD and 116 KD at cotyledonary stage. The protein pattern changes by ABA or cold treatment occurred simultaneously and mainly in acid-soluble proteins during somatic embryo development and artificial seed germination. Therefore it is suggested that the metabolic changes for adaptation to environmental change occur during somatic embryo development and the germination and growth of seedling from embryo.

• Food Science and Preservation
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• v.18 no.4
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• pp.612-619
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• 2011

Cronobacter sakazakii has been isolated from a wide range of environmental sources and from several foods of animal and plant origin. The objective of this study was to determine the resistance of C. sakazakii (ATCC 12868, ATCC 29004, and ATCC 29544) in cold, cold-freeze thaw, cold-acid, and cold starvation-freeze thaw stress. The number of C. sakazakii decreased to 1 log CFU/mL at $5^{\circ}C$ (cold storage) for 10 days. When C. sakazakii was cultivated at a low temperature ($13^{\circ}C$), the population of C sakazakii ATCC 12868 and 29004 increased to $10^9$ CFU/mL, and the population of C. sakazakii ATCC 29544 increased to $10^8$ CFU/mL. For C. sakazakii ATCC 12868 and 29004, the cold-adapted cells ($5^{\circ}C$ 24 hr) decreased by 4 log CFU/mL, and the low-temperature-cultivated cells ($13^{\circ}C$) decreased by 0.5 log CFU/mL. In this study, low-temperature cultivation enhanced the freeze-thaw cross-resistance due to the metabolic changes in the cells. Cold stress ($5^{\circ}C$ 48 hr, $13^{\circ}C$ cultivation) enhanced the cold-acid cross-resistance. The cold-starved cells in the sterilized 0.1% peptone water enhanced the freeze-thaw cross-resistance with significant differences (p<0.05). Therefore, the increased tolerance of the cold-adapted or low-temperature-cultivated C. sakazakii cells to freeze-thaw, acid, or starvation suggests that such environments should be considered when processing minimally processed foods or foods with extended shelf life.

• Animal Systematics, Evolution and Diversity
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• v.11 no.2
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• pp.159-166
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• 1995

Mature larva and male and female adults of an ephemerid mayfly (Ephemeroptera : Ephemeridae) ,Ephemera separigata n.sp., were described from Korea. Larvae and adults of the species were distinguished from other Ephemera spp. by a apir of narrow and laterally oriented longitudinal stripses on the abodminal terga 7-9 . Larvae of the species adapted to cold water high mountain torrents(altitude 500-700m) where substrates were sand, gravel, and a large portion of pebbles and cobbles. Altitudinal adaptations between Korean Ephemera spp. were briefly discussed.