• Korean Journal of Environmental Biology
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• v.40 no.3
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• pp.247-254
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• 2022

To investigate the tolerance limit and critical thermal maximum (CTM), behavioral responses of wild goldeye rockfish Sebastes thompsoni according to exposure to high water temperature were observed using a continuous behavior tracking system. As a result, behavioral index (BI) of S. thompsoni in each temperature (20.0, 25.0, and 30.0℃) showed a significant difference (p<0.05) when compared with the value measured in a stable condition of 15.0℃. The activity level of S. thompsoni exposed to 25.0℃ decreased sharply after 20 hours. Their rest time at the bottom of experiment chamber increased, and their normal swimming and metabolic activities were disturbed. In addition, at a high water temperature of 30.0℃, S. thompsoni reached the limit of resistance and showed a sub-lethal reaction of swimming behavior, with energy consumption in the body increased and all test organisms died. In conclusion, the eco-physiological response of S. thompsoni to water temperature varied greatly depending on the fluctuation range of the exposed temperature and the exposure time. In addition, the tolerance limit of S. thompsoni to high water temperature was predicted to be 25.0-30.0℃. The maximum critical thermal that had a great influence on the survival of this species was found to be around 30.0℃.

• Korean Journal of Food Science and Technology
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• v.20 no.2
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• pp.200-204
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• 1988

Cryoprotectivity of garlic bulb caused by the freezing point depression was studied to establish the possibility of preserving the garlic at subzero temperature. Freezing point of fresh garlic tissue showed almost consistency, ranged from $-4^{\circ}C\;to\;-5^{\circ}C$ regardless of the cultivation area. However, the freezing point was varied with the postharvest treatment and storage conditions, so that freezing point of fresh garlic was $-3.5^{\circ}C$ before predrying, $-4.5^{\circ}C$ after predrying, $-5.5^{\circ}C$ after 5 months of storage and that of dead tissue was $-2.5^{\circ}C$. Freezing lethality of fresh garlic bulb preserved at -4, -6.5 and $-15.5^{\circ}C$ were 0, 10 and 70%, respectively. From these results, it was concluded that critical lethal temperature might be $-5{\sim}-6^{\circ}C$. The respiration rate of garlic bulb decreased with lowering the storage temperature down to $-4^{\circ}C$. $Q_{10}$ value was 2 at the temperature range of $-4{\sim}-5^{\circ}C$, 3 at $5{\sim}15^{\circ}C$ and 1.2 at $15{\sim}37^{\circ}C$. In conclusion, optimal temperature for garlic storage was $-4^{\circ}C$ when considering the cryoprotectivity of garlic bulb at subzero temperature.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.5
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• pp.67-73
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• 2017

The concrete pavement slabs that suffer expansion due to the Alkali-Aggregate Reaction(AAR) increase and the increase consequently causes unexpected displacement of bridge abutment. As the expansion due to the AAR is greater than that due to the temperature change, lethal load can act on bridge abutment. Therefore appropriate preventive measures may be necessary. The degree of expansion by AAR depends on the severity of AAR and geometry condition of concrete pavement and road structure. In order to prevent damage to bridge, it is effective to release the expansion force of the concrete. It would be advantageous to replace the concrete pavement with asphalt for a long section of concrete pavement.

• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.2
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• pp.123-127
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• 2004

Normally, silkworms, Bombyx mori, generate offspring by sexual activity. As we known, the hybrids of the first generation of the silkworm have higher cocoon production than pure lines. During the sericulture production, many processes are related with sex control. For example, sex sorting in the egg grainages, rearing of only male silkworm to save the mulberry leaf consumption and increase silk output and quality. Therefore it is very interested in understanding the sex control of the silkworm in theory and practice. Chinese sericultural scientists have been being engaged in the researches in the fields of artificifial parthogenesis, dispermic androgenesis, sex-limited varieties, sex linkage balanced lethal strain and high temperature sensitive male stocks for several decades and gained substantial achievement. Some of the achievements have been used in the commercial production. In this review, the authors introduced that the methods for control of the silkworm sex, and regulate the silkworm sex ratio according to different producing aim in the world and especially in China.

• Microbiology and Biotechnology Letters
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• v.20 no.6
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• pp.642-646
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• 1992

We have isolated conditional lethal mutants of Saccharomyces cerevisiae which are low in (1 ~3)-~-D-glucan synthase activity. These mutants were osmotic sensitive at nonpermissive temperature (37$^{\circ}$C) and showed a decreased level of alkali-insoluble cell wall glucan. The decrease in (1 ~3)-~-D-glucan synthase activity of the mutants appeared to be mainly due to the defect in catalytic component rather than in GTP-binding component.

• Journal of the Korean Data Analysis Society
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• v.20 no.6
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• pp.2721-2731
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• 2018

This study purposes to derive the predictive model for the cold tolerance of Brassica napus, using the data collected in the Tree Breeding Lab of Gyeongsang National University during July and August of 2016. Three Brassica napus samples were treated at each of low temperatures from $4^{\circ}C$ to $-12^{\circ}C$ by decrement of $4^{\circ}C$, step by step, and electrolyte leakage levels were measured at each stage. Electrolyte leakages were observed tangibly from $-4^{\circ}C$. We tried to fit the six nonlinear regression models to the electrolyte leakage data of Brassica napus: 3-parameter logistic model, baseline logistic model, 4-parameter logistic model, (4-1)-parameter logistic model, 3-parameter Gompertz model, and (3-1)-parameter Gompertz model. The baseline levels of the electrolyte leakage estimated by these models were 4.81%, 4.07%, 4.19%, 4.07%, 4.55%, and 0%, respectively. The estimated median lethal temperature, LT50, were $-5.87^{\circ}C$, $-6.31^{\circ}C$, $-6.05^{\circ}C$, $-6.35^{\circ}C$, $-4.98^{\circ}C$, and $-5.15^{\circ}C$, respectively. We compared and discussed the measures of goodness of fit to select the appropriate nonlinear regression model.

• Journal of the Korea Institute of Military Science and Technology
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• v.24 no.6
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• pp.638-644
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• 2021

Infrared guided weapons act as threats that greatly degrade the survivability of combat aircraft. Infrared weapons detect and track the target aircraft by sensing the infrared signature radiated from the aircraft fuselage. Therefore, in this study, we analyzed the infrared signature and susceptibility of supersonic aircraft according to omni-directional detection angle. Through the numerical analysis, we derived the surface temperature distribution of fuselage and omni-directional infrared signature. Then, we calculated the detection range according to detection angle in consideration of IR sensor's parameters. Using in-house code, the lethal range was calculated by considering the relative velocity between aircraft and IR missile. As a result, the elevational susceptibility is larger than the azimuthal susceptibility, and it means that the aircraft can be attacked in wider area at the elevational situation.

• Applied Biological Chemistry
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• v.13 no.3
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• pp.193-195
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• 1970

The cultural conditions of the osmophilic yeasts for higher concentration of NaCl selected in the previous report were examined and the results obtained were as follows. 1) The strain $T_3\;and\;T_8$ were grown exceedingly well on the media containing 15 percent of NaCl and $T_5\;and\;T_9,\;T_{10}\;and\;T_{11}$ on the media containing 5 percent of NaCl. 2) The optimum temperature for growth of the strain $T_3\;and\;T_5$ was $30^{\circ}C,\;T_8\;T_{10}$ and $T_{11}\;was\;25^{\circ}C\;and\;T_9\;was\;35^{\circ}C.$ 3) Their lethal temperature was $60^{\circ}C$ (treatment for 10 minutes). 4) The optimum pH for growth of the strain $T_3\;and\;T_8$ was pH 4.0, $T_5$ was pH 6.0 and $T_9\;T_9\;and\;T_{11}$ was pH 5.0, respectively.

• Korean journal of applied entomology
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• v.36 no.3
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• pp.249-255
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• 1997

The sublethal temperature (5$^{\circ}$C for 2hr) led the fifth instar larvae of beet armyworm, Spodoprern exigucr (Hiibner), to increase cold tolerance to subzero lethal temperatures ( 'rapid cold hardening' ). The strength of rapid cold hardening was, however, varied among different populations which showed different cold tolerance in response to cold temperatures. To analyse the physiological factors affecting the rapid cold hardening, hernolymph osmolalities. supercooling points, glycerol contents, and cold stress proteins were measured by treating the fifth instar larvae with the sublethal low temperatures. The treated larvae showed increase of hemolymph osmolalities and glycerol contents. Changes of the osmolalities were greater in cold-hardy strains than in cold-susceptible strains. The sublethal temperature also induced them to express the cold-stress proteins (I0 - 20kD) in the hemolymph. but did not to change supercooling points.

• Korean Journal of Microbiology
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• v.9 no.2
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• pp.55-60
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• 1971

Among 50 yeasts of red pepper paste isolated and identified in the previous report, 12 strains of yeast which possess osmophilic and non-film characteristics were examined their growth rates and alcohol fermentation ability in red pepper medium. 5 strains of yeast possessing powerful growth rates and excellent alcohol fermentation ability were selected as excellent yeasts in this experiment. And their cultural conditions, salt resistance and red pepper concentration upon the growth were examined in this report. The results obtained were as follows ; 1) Among 12 strains of yeast, Saccharomyces cerevisiae group II(strain $D_1$), Saccharomyces oviformis($D_2$), Saccharomyces steineri($M_3$), Saccharomyces rouxii($D_9$) and Saccharomyces mellis($G_8$) were selected as excellent yeasts. 2) Among 5 strains of yeast selected, the strain $D_1$ and $D_2$showed the best alcohol fermentation ability and the best fermentative flavour. 3) The optimum temperature for growth of the strain $D_1$ and $D_2$ was $25^{\circ}C$$M_3$, $D_9$ and $G_8$ $30^{\circ}C$$D_1$ and $D_2$ was $62^{\circ}C$$M_3$,$D_9$ and $G_8$ ws 60.deg.C with treatment for 10 minutes. 4) The optimum pH for growth of all strains was around 5.0. 5) The strain $D_1$ and $M_3$were grown exceedingly well on the emdia containing 3 percent of NaCl and $D_2$,$D_9$ and $G_8$ on the media containing 6 percent of NaCl. 6) In the case of 5 percent of red pepper liquor added 5 percent of glucose was more nutritional than in the case of 5 percent glucose only. However, the growth rates of yeasts were restrained by the increase of red pepper concentration.