• The Korean Journal of Nuclear Medicine
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• v.33 no.2
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• pp.152-162
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• 1999

Purpose: To determine whether $^{99m}Tc$-MIBI is recognized by the multidrug resistant P-glycoprotein (Pgp), we have measured quantitatively $^{99m}Tc$-MIBI uptake in cancer cells. The effects of various Pgp reversing agents on cellular $^{99m}Tc$-MIBI uptake were also investigated in the presence of multidrug resistance gene-1 (mdr1 gene) overexpression. Materials and Methods: We measured percentage uptake of $^{99m}Tc$-MIBI at different incubation temperatures both in mdr1 positive and negative cells. The effects of verapamil, cyclosporin, and dipyridamole on cellular uptake of $^{99m}Tc$-MIBI were also evaluated with or without overex-pression of mdr1 gene in cultured murine leukemia Ll210 cells. Results: The mdr1 gene expressing cell lines were effectively induced in in vitro with continuous application of low-dose adriamycin or vincristine. Cellular uptake of $^{99m}Tc$-MIBI was higher in mdr1 negative Ll210 cells than those of mdr1 positive cells, and higher when incubated in $37^{\circ}C$ than $4^{\circ}C$. In the presence of verapamil, cyclosporin or dipyridamole, $^{99m}Tc$-MIBI uptake was increased upto 604% in mdr1 positive cells. Conclusion: Cellular uptake of $^{99m}Tc$-MIBI is lower in leukemia cells over-expressing mdr1 gene, and MBR-reversing agents increase cellular uptake. These results suggest that $^{99m}Tc$-MIBI can be used for characterizing Pgp expression and developing MDR-reversing agents in vitro.

• Journal of the Korean association of regional geographers
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• v.4 no.2
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• pp.165-182
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• 1998

When tour site is being used by people for the destination of tour, it has a life, or it will lose its life as a tour site. Therefore this paper aims to, based on Butler's theory, has chosen 46 hot spring spots in Korea which are legally assigned and presently running, and tried to analyze the life cycles, the stage of dispositional characteristics, and visitors' favoritism, and to try to find activating method which is not decline. Out of 46 spots, 29 Places were found on the stage of development, which took high percentage, 4 were on the growing stage, 5 were on the mature stage, 5 were on the stagnation or decline stage and the rest 3 were on the stage of rejuvenation. Geographically, Korean hot springs were located on the plain or mountainous areas mostly, and less of them were on hills and coast lines. In water quality, most of places had simple water while the places with salt and sulfur contained water were marked low rate. The temperatures of hot spring water were variable between $25^{\circ}C{\sim}78^{\circ}C$, but the older hot springs were hotter than new ones. After observing the relationship between disposition characteristics and life cycles, the geographical locations and the matter of approach were found as majour influential factors to the life cycles of them. The type of mountainous areas were observed slow progress in life cycle, due to traffic problem, until the road expansion or pavement work were done. Meanwhile, the suburban ones adjacent to big cities were favored by hot spring tourists due to their easy approach and easy traffic. The new born hot springs with such conditions have shown the fast growth. As studied above, since the hot springs were supposed to be for recuperation and vacational, a hot spring with better recreational and accommodational facilities was more favored by tourists than the one with pretty interior decorations. It was because the tour purpose of people has been switched from single purpose to multi one. Thus, the suggestion for activating a declining hot spring and bringing people in them is to develop new and attractive tour resources, expanding the related area, maintaining good quality of water, developing a complex site for long-term tour, developed traffic routs, hot spring festivals, utilizing adjacent tour resources, preparing public water supply system, and assigning as special tour zone.

• Journal of Embryo Transfer
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• v.32 no.1
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• pp.1-8
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• 2017

Cryopreservation of germ cells from genetically proven animals could be a source of restoration tools from the risk of extinction or disappearance of wanted characteristics. Using frozen semen, the genetic gains of Korean native cattle have been increased greatly for 70 years. The preservation of genetic resources as a form of frozen semen straw has limited availability due to the numbers. To circumvent this weakness of frozen semen, we tested two re-freezing methods with different initial thawing temperatures using frozen Korean proven semen and rare breed semen from albino, black and chikso breeders. It has been known that human sperm could resist to cryo-damages by repeated freeze-thaw cycles, but not for Korean proven bulls number (KPN) or for rare breeds. Total 7 frozen semem from brindled(2), black(1), Korean Albino(2) and KPN(1) bulls were used for our research. After thawing straws under $5^{\circ}C/2min$ or $37^{\circ}C/40sec$ with low temperature water bath and thermo jug, spermatozoa were re-diluted with triladyl diluents after first thawing and re-frozen. Sperm motilities were compared between animals and treated groups after re-thawing. Mean values of motility and viability of refrozen/thawed sperm for expansion of the number of straws were significantly higher in $5^{\circ}C$ than in $37^{\circ}C$ (P < 0.05). However, the activity of viable sperm thawed at $5^{\circ}C$ was significantly decreased before refreezing. It is estimated that re-freezing of frozen semen from rare Korean native cattle is possible with resistant properties of survived spermatozoa.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.9
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• pp.4602-4609
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• 2013

In summer and winter, the difference between the temperature during the day and that during the night is high, which leads to various problems during concrete placement, such as cracks and defects in the concrete as well as low durability and strength. Although nuclear power plant concrete is widely used for placement in all seasons, particular attention must be paid to its quality during the summer. Therefore, we evaluated the effects of a cooling method for mixing water, which is a commonly used hot weather precooling method, and the use of a retarder, on the characteristics of Nuclear Power Plant concrete. In the cooling method for mixing water, cold water at 5 was used, with 50% of the water content consisting of ice flakes. The effects of using a retarder were evaluated by reviewing the characteristics of the cement at the unset stage and after hardening. To evaluate the characteristics of the unset cement, we measured the slump, air volumes, setting times, and pressure strengths after hardening. Furthermore, we measured the heat of hydration at different temperatures; the loss of heat was minimized using insulation. Both the slump time and the complete ageing time of the air volume were found to be 120 min at $20^{\circ}C$ and 40 min at $40^{\circ}C$. In the case when the cooling method for mixing water was used and in the case when a retarder was used, the initial and final sets by penetration resistance were delayed, and the delay decreased with increasing air temperature. For the heat of hydration, the cooling method for mixing water not only lowered the maximum temperature but also delayed its attainment. However, the use of a retarder had no effect on the maximum temperature. Moreover, in the early ages (e.g., 3 and 7 days), the pressure strength of the concrete was lower than that of plain cement. However, the strength of 28-day concrete met the standard construction specifications.

• Horticultural Science & Technology
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• v.33 no.5
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• pp.687-696
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• 2015

Black mini tomato 'Hei-G' fruits were harvested at different stages of maturity (immature-mature green and mature-black red) and stored at different temperatures (8, 12, and $20^{\circ}C$) to investigate the quality and lycopene content during storage. Weight loss increased dramatically at higher temperature for both harvesting stages without significant differences. Firmness of immature fruits decreased below the initial level of mature fruit (8.1N) after 5, 8, and 19 days storage, when they were stored at 20, 12, and $8^{\circ}C$, respectively. Soluble solid contents of mature fruit increased at initial storage, and were higher as compared to immature fruits before deterioration at each storage temperature. Decrease in titratable acid of mature fruits depended on storage time and temperature. However, titratable acid of immature fruits showed little change during storage, and so it did not affect flavor. Hunter a value changed greatly in immature fruit stored at high temperature. Unlike ripe tomatoes, there was no significant difference in black tomato Hunter b values of immature and mature fruit at initial and 12 days storage. However, immature fruits stored at $8^{\circ}C$ did not reach full maturity and color development and ripening. High storage temperature increased lycopene production while low storage temperature blocked lycopene development. Shelf life of the immature fruits, which was evaluated by elapsed days to conventional mature stage, was 12 and 15 days when they were stored at 20 and $12^{\circ}C$, respectively. The optimum storage temperature to maintain the quality and lycopene content of mature fruits was $12^{\circ}C$. Moreover, the shelf life of mature fruits stored at $20^{\circ}C$ could reach up to 5 days.

• Journal of Food Hygiene and Safety
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• v.29 no.2
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• pp.158-163
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• 2014

In this study, two commercial PCR and ELISA test kits were examined for identification of eight animal species (beef, pork, chicken, duck, turkey, goat, lamb, and horse) from raw meat and meat products in Korea. The detection limit in RAW meat ELISA kit$^{(R)}$ on three types of meat samples blended with beef, pork and chicken, demonstrated that all meat species were differentiable down to 0.2%. RAW meat ELISA kit$^{(R)}$ on animal species resulted in differentiation rate of 94.5% for beef, 93.3% for pork, 90% for lamb, and 100% for chicken, duck, turkey, goat, and horse. In contrast, Powercheck Animal Species ID PCR kit$^{TM}$ resulted in 100% specificity at 0.05% limit of detection for all meat species. The detection limit of Cooked Meat ELISA kit$^{(R)}$ on mixed meat samples heat-treated with different temperatures and times, resulted in 0.1% for all heat-treated mixed meat except for chicken at 1.0%. Additionally, ELISA kit on sixty meat products resulted in specificity of 31.8% for ham, 13.6% for sausages, and 12.5% for ground processed products, and relatively low rate for more than 2 types of mixed meats. On the contrary, meat species differentiation using PCR kit showed higher percentage than that using ELISA kit$^{(R)}$: 50.0% for ham, 41.7% for sausages, and 28.6% for ground processed meat. Futhermore, PCR kit on 54 dried beef meats detected pork genes in 13 products whereas ELISA kit showed negative results for all products. Hence, the possibility of cross-contamination during manufacturing process was investigated, and it was found that identical tumblers, straining trays, cutters and dryers were used in both beef and pork jerky production line, suggesting the inclusion of pork genes in beef products due to cross-contamination. In this study, PCR and ELISA test kits were found to be excellent methods for meat species differentiation in raw meat and heat-processed mixed meat. However, lower differentiation rate demonstrated in case of meat processed products raised the possibility of inclusion of other species due to cross-contamination during manufacturing process.

• Journal of Bio-Environment Control
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• v.10 no.1
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• pp.15-22
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• 2001

A soil temperature was known as extremely important factor in terms of measuring the values of the growth and yield of vegetable in the greenhouse. A low temperature water irrigation was had much trouble in its growth. This study was performed to analyze the effect of the heating water irrigation on the soil temperature and the growth of a cucumber within a greenhouse environment. Soil temperature was 5-7$^{\circ}C$ below to 10cm in depth and 2-3$^{\circ}C$ to 20cm when the irrigation water temperature was 13$^{\circ}C$ (non-warme water irrigation). Soil temperature was similar to irrigation water temperature at 5cm in depth and was 1.5-2$^{\circ}C$ below at 10cm when the irrigation water temperatures were 2$0^{\circ}C$, $25^{\circ}C$. The early growth rates of heating water irrigation were 109-110% in plant height, 107-108% in leaf number, 103% in node number compared with those of unheated water irrigation for 30 days after planting it. The rates of total yield were 115% in 2$0^{\circ}C$ water irrigation plots and 121% in $25^{\circ}C$ water irrigation plots while those of unheated water irrigation plots were.

• Journal of agriculture & life science
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• v.43 no.5
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• pp.17-25
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• 2009

The purpose of this study was to find out the optimum germination temperature and dehydration period at SMP processing, and applies 3 kind of seed treatment and compares yield with stand establishment of seeds of 12 pepper cultivars. It was showed that all 12 cultivars of nontreated seed does not entirely germinated in $15^{\circ}C$. It was that SMP seed germination rate 77(Yeomyeong)~100% (Deawang) high, and seeds 12 cultivars was tendency high by more than 93% at all temperatures excepting Bugang($35^{\circ}C$, 85%) and Yeomyeong($15^{\circ}C$, 77%). Dehydration condition of result were Gumsure, Dongbang Jonggagip, Hyangchon, Yeomyeong, Kwangbok, Wang by which 3 hours in $45^{\circ}C$ were proper, which 6 hours in $35^{\circ}C$ were proper Manitta, Joyang, and judged that 12 hours in $25^{\circ}C$ were proper in Bugang, Dabotap, Deawang. It was reported that water percentage of moisture content change of pepper seed by dehydration was difference a little in species, but was judged by 3-6 hours in $45^{\circ}C$. There was compared to SMP, Osmopriming, pH control by stand establishment were shown pH control of Hyangchon, Dabotap species was nontreated, osmopriming treatment. Also, Kwangbok species was tendency that stand establishment was low, and Deawang was good than other species. Yield of nontreated of yield day was tendency, and miss planted rate also appeared high for 90 day. There was difference in species, and processing of pH control and osmopriming was not shown stand establishment that is stabilized in all species. SMP processing condition could bring security of stable stand establishment in all species, and was considered that research that was under various environment condition should be proceeded conclusively.

• Food Science and Preservation
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• v.25 no.1
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• pp.44-51
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• 2018

The purpose of this study is to present the results as basic data for establishing proper storage conditions and distribution conditions of actual farms at point of increasing concern about hygiene and palatabiltiy of consumers to food. In this study, three farmhouses of dried persimmons prepared using different storage conditions were selected in Sangju (Korea). The dried persimmons were stored for 90 days. Changes in temperature and humidity were measured with a temperature and humidity recorder under each storage condition, and physicochemical analysis and sensory evaluation were performed. The average temperatures of farmhouse A, B and C were approximately $-22--23^{\circ}C$, $-19--18^{\circ}C$ and $-25^{\circ}C$ respectively. The humidities of A, B and C were 62-63%, 59-60%, and 66-67%, respectively, and the moisture contents of all farmhouses increased during the storage period, with farmhouse B showing the most rapid increase. Free sugars increased, except for those from farmhouse C. Persimmons from farmhouse B showed the greatest changes in chewiness and hardness. The values of $a^*$ and $b^*$ were significantly decreased in persimmons from farmhouse B, and the color difference value of farmhouse B was dramatically increased. Sensory evaluation showed that the color preference tended to decrease compared with the initial value. Only farmhouse B showed decreased overall acceptability. Moreover, farmhouse B had the highest storage temperature and lowest humidity. Therefore, our results showed that storage at a low temperature and high humidity was important for manufacturing high-quality dried persimmons.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1108-1119
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• 2018

As the interest on the air pollution is gradually rising at home and abroad, automotive and fuel researchers have been studied on the exhaust and greenhouse gas emission reduction from vehicles through a lot of approaches, which consist of new engine design, innovative after-treatment systems, using clean (eco-friendly alternative) fuels and fuel quality improvement. This research has brought forward two main issues : exhaust emissions (regulated and non-regulated emissions, PM particle matter) and greenhouse gases of vehicle. Exhaust emissions and greenhouse gases of automotive had many problem such as the cause of ambient pollution, health effects. In order to reduce these emissions, many countries are regulating new exhaust gas test modes. Worldwide harmonized light-duty vehicle test procedure (WLTP) for emission certification has been developed in WP.29 forum in UNECE since 2007. This test procedure was applied to domestic light duty diesel vehicles at the same time as Europe. The air pollutant emissions from light-duty vehicles are regulated by the weight per distance, which the driving cycles can affect the results. Exhaust emissions of vehicle varies substantially based on climate conditions, and driving habits. Extreme outside temperatures tend to increasing the emissions, because more fuel must be used to heat or cool the cabin. Also, high driving speeds increases the emissions because of the energy required to overcome increased drag. Compared with gradual vehicle acceleration, rapid vehicle acceleration increases the emissions. Additional devices (air-conditioner and heater) and road inclines also increases the emissions. In this study, three light-duty vehicles were tested with WLTP, NEDC, and FTP-75, which are used to regulate the emissions of light-duty vehicles, and how much emissions can be affected by different driving cycles. The emissions gas have not shown statistically meaningful difference. The maximum emission gas have been found in low speed phase of WLTP which is mainly caused by cooled engine conditions. The amount of emission gas in cooled engine condition is much different as test vehicles. It means different technical solution requires in this aspect to cope with WLTP driving cycle.