• The Journal of the Korean Society for Microbiology
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• v.22 no.1
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• pp.23-33
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• 1987

To detect lepotospiral strains which produce hemolysin and determine the optimal condition for assaying hemolysin, we screened reference strains and observed some property of hemolysin. Hemolysin activity was assayed with cell free culture liquids and erythrocyte suspension. The production of hemolysin by local strains isolated in Korea was assayed and compared with that of reference strains. The hemolysin was produced by 18 strains among 38 reference strains and 3 local strains isolated in Korea. The production of hemolysin began with growth of Leptospira cultured in EMJH medium and reached maximum at stationary phase. The optimum temperature for hemolytic activity was $37^{\circ}C$. At lower temperature the activity of hemolysin was decreased progressively. The hemolytic activity was completely inactivated after :30 minutes' exposure at $56^{\circ}C$. Hemolysis pattern was "hot-cold type" which showed increased hemolysis after cold incubation. The hemolysin was most active on sheep erythrocyte and less active on ox, goat, human and guinea pig erythrocyte with the decreasing order.

• Journal of Microbiology
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• v.44 no.4
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• pp.466-471
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• 2006

In this study, we attempted to characterize the biomolecular effects of an atmospheric-pressure cold plasma (APCP) system which utilizes helium/oxygen $(He/O_2)$. APCP using $He/O_2$ generates a low level of UV while generating reactive oxygen radicals which probably serve as the primary factor in sterilization; these reactive oxygen radicals have the advantage of being capable to access the interiors of the structures of microbial cells. The damaging effects of plasma exposure on polypeptides, DNA, and enzyme proteins in the cell were assessed using biochemical methods.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.221-224
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• 2005

In order to traffic safety during winter season, snowfall and cold area has been spread the deicing chemicals, and the spraying amount is increasing every year. Use of deicing chemicals has been and will continue to be a major part of highway snow and ice control methods. Chloride-containing chemicals such as calcium chloride or rock salt are main deicers for the road. Extensive use of chloride deicers is, however, the source of substantial cost penalties due to their corrosive action and acceleration to deterioration concrete structures. Deterioration due to de-icer salt occurs in practice in concrete pavement, dike, barrier and similar structure. This paper reports the results of effect of de-icer salt on durability of concrete structure in winter. To protect concrete structure from damage by de-icer salt in winter, the exposure test was performed using three methods such as increase in design strength upto 35MPa application of granulated blast furnace slag powder, and concrete sealer. Of these, the method of increase in design strength upto 35MPa showed better durability for deterioration by de-icer salt.

• Advances in Energy Research
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• v.5 no.4
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• pp.289-304
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• 2017

Large glazed surfaces and windows become common features in modern buildings. The spread of these features was influenced by the dependence of designers on mechanical and artificial systems to provide occupants with thermal and visual comfort. Countries with hot summer and cold winter conditions, like Jordan, require maximum shading from solar radiation in summer, and maximum exposure in winter to reduce cooling and heating loads respectively. The current research aims at designing optimized double-positioned external shading device systems that help to reduce energy consumption in buildings and provide thermal and visual comfort during both hot and cold seasons. Using energy plus, a whole building energy simulation program, and radiance, Lighting Simulation Tool, with DesignBuilder interface, a series of computer simulations for energy consumption and daylighting performance were conducted for offices with south, east, or west windows. The research was based on comparison to determine the best fit characteristics for two positions of adjustable horizontal louvers on south facade or vertical fins on east and west facades for summer and winter conditions. The adjustable shading systems can be applied for new or retrofitted office or housing buildings. The optimized shading devices for summer and winter positions helped to reduce the net annual energy consumption compared to a base case space with no shading device or with curtains and compared to fix shading devices.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.6
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• pp.795-801
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• 2005

Eighteen Suffolk wether lambs (BW = 24 kg) were chronically exposed to temperatures of cold (2$^{\circ}C$) or warm (22$^{\circ}C$). The experimental design consisted of a 2${\times}$3 factorial with a single crossover of environment treatment. The sheep were closely shorn and were housed in individual metabolic crates in controlled environment rooms. Sheep consumed pelleted diets ad libitum, which consisted of mainly barley grain and brome grass, and diets contained 7, 11 or 14% crude protein (CP). Animals were catheterized via one jugular vein with a PVC catheter and received a single injection of 60-65 Ci of $^{14}$C]urea. Plasma urea-N (PUN), urinary urea (UU), and carbon specific radioactivity were measured. Urea metabolism was not affected by environment. Percent urea recycling and urea space clearance were highest (p<0.05) on the low nitrogen diet. Urea pool was increased (p<0.10) for the 14% CP diet. Both UU and PUN concentration were positively related (p<0.01) with diet CP content. Therefore, dietary CP content significantly influenced urea metabolism, however, cold exposure did not alter those parameters.

• Bulletin of the Korean Chemical Society
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• v.31 no.4
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• pp.887-890
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• 2010

The family of ClpB protein is a molecular chaperone which protects cellular proteins from being aggregated upon exposure to severe environmental stresses in association with DnaK/DanJ/GrpE in the ATP-dependent manner. In a psychrophilic bacterium which survives at a subzero temperature, any functional role of cold-active ClpB protein can be rather crucial. In order to identify a ClpB encoding gene from a cold-adapted bacterium whose genome sequence has not been fully discovered, we have employed a series of PCR technologies, including a gradient PCR with homologous primers, an inverse PCR and a cassette PCR. The full sequence of PaclpB gene was successfully identified and compared with those of other psychrophilic species. We have further cloned the gene in E.coli expression systems and were able to induce PaClpB protein expression by IPTG, which help us understand a molecular mechanism for survival against extremely cold environments.

• Science of Emotion and Sensibility
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• v.14 no.3
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• pp.425-434
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• 2011

In the present study was to examine the influence of cold stress conditions on memory function in relation with 5-hydroxytryptamine(serotonin, 5-HT), trptophanhydroxylase(TPH) expression and cell proliferation in the hippocampus. For this study, male Sprague-Dawley rats weighing $250{\pm}10g$ (7 weeks in age) were used. The rats were randomly divided into three groups(n = 10 in each group): the $22^{\circ}C$-control group, the $4^{\circ}C$-3 days group, the $4^{\circ}C$-5 weeks group. The environmental temperature at $22^{\circ}C$ set as the normal conditions, $4^{\circ}C$ was as the cold stress conditions. The present results showed that cold stress conditions shorten latency, representing cold stress disturbed memory function. 5-HT and TPH expressions in the dorsal raphe were increased cold stress. Neurogenesis in the dentate gyrus was increased under cold conditions. The present study revealed that cold stress exerted deteriorative memory function. However, through increasing of 5-HT, TPH and BrdU expression under cold stress conditions did not show memory enhancing effect.

• Journal of the Korean Society of Clothing and Textiles
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• v.43 no.6
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• pp.866-876
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• 2019

This study examined the physiological and psychological effects of wearing gloves at rest in a cold environment. Seven elderly females participated in two separate trials: wearing gloves (WG) and bare hands (BH). The experiment was conducted for 60 min in a climatic chamber (air temperature 7.8±0.3℃ with 44±2%RH) with a sedentary posture. Microclimate temperature on the left palm was 4.16℃ higher in WG compared to that in BH (p<.1). Microclimate temperature on the chest during the last 5 min increased compared to the initial 5 min only in WG (p<.05). During the last 5 min, skin temperatures at the arm and hand in WG were higher than those in BH (p<.05). There was no statistical difference in the change of rectal temperature between WG and BH. Heart rate in BH was significantly higher compared to the WG (p<.05). Subjects also felt less cold on the whole body and hand in WG than those in BH (p<.05). The findings indicate that wearing gloves for elderly females affected the distribution of skin temperature and cardiovascular response in cold environments. Elderly females should be informed about the importance of wearing gloves through the clothing guideline in winter.

• Journal of the Korean Society of Clothing and Textiles
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• v.15 no.4 s.40
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• pp.447-451
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• 1991

Effects of insulation after exposure of the extremities on the temperature regulation in clothed men were studied. Experiment was carried out with six males in a climatic chamber fixed at $10^{\circ}C$, $55\%$ R.H. treated with Type A (face only was exposed) and Type B (face and half of the extremities were exposed). Mean skin temperature fell greater in Type B due to intense vasoconstriction than in Type A. Rectal temperature rose a little in Type B and resumed in Type A without any significant differences in metabolism between two types of clothing. These findings suggest that Type B is more effective in physiological defense to the cold stimuli than Type A at least at $10^{\circ}C$.

• Computers and Concrete
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• v.5 no.6
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• pp.573-597
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• 2008

Among artificial intelligence-based computational techniques, adaptive neuro-fuzzy inference systems (ANFIS) are particularly suitable for modelling complex systems with known input-output data sets. Such systems can be efficient in modelling non-linear, complex and ambiguous behaviour of cement-based materials undergoing single, dual or multiple damage factors of different forms (chemical, physical and structural). Due to the well-known complexity of sulfate attack on cement-based materials, the current work investigates the use of ANFIS to model the behaviour of a wide range of self-consolidating concrete (SCC) mixture designs under various high-concentration sodium sulfate exposure regimes including full immersion, wetting-drying, partial immersion, freezing-thawing, and cyclic cold-hot conditions with or without sustained flexural loading. Three ANFIS models have been developed to predict the expansion, reduction in elastic dynamic modulus, and starting time of failure of the tested SCC specimens under the various high-concentration sodium sulfate exposure regimes. A fuzzy inference system was also developed to predict the level of aggression of environmental conditions associated with very severe sodium sulfate attack based on temperature, relative humidity and degree of wetting-drying. The results show that predictions of the ANFIS and fuzzy inference systems were rational and accurate, with errors not exceeding 5%. Sensitivity analyses showed that the trends of results given by the models had good agreement with actual experimental results and with thermal, mineralogical and micro-analytical studies.