• Applied Microscopy
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• v.31 no.2
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• pp.207-214
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• 2001

Anatomy and ultrastructure of the modifeid Krana pattern have been studied in succulent Salsola collina Pall. Cylindrical leaves exhibited the Salsoloid Kranz type containing two layers of peripheral chlorenchyma that surrounded the water storage cells and vascular tissues. Small veins were also peripherally arranged, but mostly embedded in the vicinity of the inner chlorenchma without the orderly arrangement of the concentric layering of bundle sheath and mesophyll cells. The current study mainly focused on the chlorenchyma tissue abutting such minor veins. The outer columnar layer exhibited features similar to the characteristics of palisade mesophyll cells, while the inner cuboid layer to the bundle sheath cells of a typical $C_4$ Kranz pattern. Cellular components of the inner chlorenchyma were centripetal and numerous, but starch-laden chloroplasts were rudimentary in the thylakoidal system. The outer chlorenchyma demonstrated normally developed chloroplasts having well-stacked thylakoids and plastoglobuli. Branched and complicated plasmodesmata frequently occurred in thick interfaces of the two layers, implying the active movement of the photosynthates between them. The present data were mostly congruent with one of the structural features of the C4 subtypes , NADP-ME type, reported in the $C_4$ pattern. The Kranz pattern encountered in this Salsola probably has been directly related to the structural modification that occurred during a functional adaptation to the $C_4$ photosynthesis.

• Science of Emotion and Sensibility
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• v.18 no.2
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• pp.3-18
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• 2015

Numerosity perception is considered as an innate ability of human being where its sensivitiy may widely vary across each individual person. The present study explored the relationship between visual working memory (VWM), visual search efficiency, and numerosity sensitivity. To accomplish this, we calculated each participant's K-value from change detection performance representing one's storage capacity in VWM, slopes of search RTs representing the search efficiency, and discrimination sensitivity for a quantity difference across two sets of dot arrays representing the numerosity sensitivity. The correlational analysis across the measurements revealed that participants with a high VWM capacity better discriminated the numerosity difference in the arrays when the spatial information in the two dot arrays was preserved. In contrast, the participants with high search efficiency discriminated better the difference in the arrays when the spatial information in the arrays was not preserved. The results indicate high VWM-capacity individuals were presumably able to use a strategy of storing the dot arrays by grouping them into a smaller pattern of dot arrays while high search-efficiency individuals were able to use a strategy of rapidly switching their focused attention across the dots in the arrays to count each individual dot. These in sum suggest that individual differences in numerosity sensitivity rely on one's working memory capacity as well as their efficient use of switching focused attention.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.10a
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• pp.1-11
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• 2003

The objectives of this paper are to overview present status of soil pollution in Korea, to review the current policies and management strategies for soil pollution prevention and remediation of contaminated sites, and to suggest some recommendations to be considered toward more efficient policies. Soils in Korea are contaminated mainly by industrial facilities, landfills, underground storage tanks, abandoned/inactive mines, military camps, and other sources. Concentrations of most of soil pollutants were similar to the background levels, except for a few heavily contaminated sites such as industrial sites or abandoned/inactive mines. The Soil Environment Conservation Act (SECA), which was effective from 1995, provides a comprehensive legal framework for both preventing soil pollution and remedying contaminated sites in Korea. The Act includes various management policies such as the designation of standards and soil pollution policy area, soil monitoring networks, management of suspected contamination sources, and extended 'polluter-pays' principle. To make current policies more efficient and reasonable, some policies or strategies such as the establishment of national priority list, more detailed standards, risk-based cleanup goal, fund raise, soil erosion problem, and finally, integrity between soil and groundwater management frameworks may need to be pursued in the long term.

• Journal of Soil and Groundwater Environment
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• v.14 no.3
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• pp.68-79
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• 2009

Groundwater is the main water resource in Jeju Island because storage of surface water in reservoir is difficult in the island due to the permeable volcanic rocks. Because of this reason, the groundwater is expected to be very vulnerable to seawater intrusion by global warming, which will cause sea level rise. The long term change of mean sea level around the Korean Peninsula including Jeju Island was analyzed for this study. The sea level rise over the past 40 years was estimated to be of $2.16\;{\pm}\;1.71\;mm/yr$ around the Korean Peninsula. However, the rising trend around the eastern part of Jeju Island was more remarkable. In addition, the groundwater/seawater intrusion monitoring network operated by the Jeju Special Self-Governing Province shows that seawater intrusion becomes more prominent during dry 4-5 months in a year when the sea level increases. This implies that the fresh groundwater lens in the eastern part of Jeju Island is influenced by the sea level rise due to global warming in the long term scale.

• Journal of Veterinary Clinics
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• v.30 no.4
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• pp.223-229
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• 2013

Because colostrum is considered to be the sole source of passively acquired maternal antibodies for calves, newborn calves must consume colostrum to gain disease resistance during their early years of life. Storage of surplus colostrum from dairy cows right after calving and feeding newborn calves in deficiency of colostrum to assure adequate uptake of IgG for protection of the calf has been a common practice in the bovine production. In the current study, 35 colostrums were randomly collected from 3 colostrum banks located in different regions of Korea and monitored for general bacterial contamination and major bovine pathogens. Immunoglobulin concentrations and BVDV-specific antibodies were also determined to evaluate the immune quality of the colostrums. Moderate to severe bacterial contamination (up to 72,000,000 CFU/ml) was observed in most of the colostrums collected from colostrum banks. General immune quality of the colostrums was under the satisfactory level since most of the colostrums contained less than 50 g/L of IgG, which is the minimum concentration for good quality colostrums. Therefore, colostrum for colostrum bank should be collected at the first 2-3 post-partum milkings according to proper harvesting and handling procedures to guarantee the safety and quality of colostrum. In addition, it was recommended that colostrum should be heat-treated before frozen and stored in the bank because pasteurization at $63^{\circ}C$ for 30 min was very effective reducing the risk of disease transmission without causing significant degradation of immunoglobulins.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.3
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• pp.642-648
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• 2008

The aim of this study is to investigate Chegameuiin-tang water extracts (CETE) have potent anti-obesity activities in a high fat diet-induced obesity mouse model. In this study, we designed three group (normal diet group, high fat diet group, high fat diet plus CETE group for 13-week oral administration). Increases in body weight and fat storage were inhibited by 13-week oral administration of CETE at a 500 mg/kg concentration in this animal model, while the amount of food intake was not affected. Results from blood lipid analysis showed that the levels of triglyceride, total cholesterol and LDL-cholesterol were significantly lowered by CETE administration, also HDL-cholesterol was increased more than high fat diet-induced obese mouse. To understand the underlying mechanism at the molecular level, the effects of CETE were examined on the expression of the genes involved in lipogenesis and lipolysis by real-time PCR. In epididymal fat of CETE-treated mice, the mRNA level of lipogenic genes such as sterol regulatory element binding protein 1 and fatty acid synthase were decreased, which was well correlated with the reduction of the epididymal fat weight. Also, CETE administration inhibited decreases of the hormone-sensitve lipase and lipoprotein lipase mRNA expressions, which are genes related with lipolysis. These results suggest that Chegameuiin-tang may have great potential as a novel anti-obesity agent.

• Journal of Plant Biotechnology
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• v.34 no.4
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• pp.277-283
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• 2007

Embryogenic calluses derived from shoot apical meristem explants of sweetpotato were subjected to particle bombardment to generate transgenic plants for antisense expression of cDNAs encoding two different AGPase small subunit (ibAGP1 and ibAGP2). Plants were generated via somatic embryogenesis. PCR and Southern analysis demonstrated that the incorporation of ibAGP1 and ibAGP2 into the genome in an antisense orientation. Immunoblot analysis confirmed reduced levels of AGPase small subunit in transgenic plant leaves. Plants with both ibAGP1 and ibAGP2 produced a lower level of the protein than plants with ibAGP1 alone. iodine test demonstrated that transgenic plant leaves and storage root accumulated reduced amounts of starch. Iodine staining of leaf tissues indicated that transgenic plants accumulated less amount of starch than control. In accordance with western blot analysis, plants with both ibAGP1 and ibAGP2 accumulated a lower amount of starch than plants with ibAGP1 alone. Both transgenic plants exhibited a severely retarded growth, resulting in bare survival. It is suggested that disrupted expression of the gene encoding AGPase small subunit is lethal to the growth of sweetpotato contrast to other species including potato.

• Journal of Chest Surgery
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• v.36 no.4
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• pp.219-228
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• 2003

Background:Liquid nitrogen freezing techniques have already met with widespread success in biology and medicine as a means of long-term storage for cells and tissues. The use of cryoprotectants such as glycerol and dimethylsulphoxide to prevent ice crystal formation, with carefully controlled rates of freezing and thawing, allows both structure and viability to be retained almost indefinitely. Cryopreservation of various tissues has various con-trolled rates of freezing. Material and Method: To find the optimal freezing curve and the chamber temperature, we approached the thermodynamic calculation of tissues in two ways. One is the direct calculation method. We should know the thermophysical characteristics of all components, latent heat of fusion, area, density and volume, etc. This kind of calculation is so sophisticated and some variables may not be determined. The other is the indirect calculation method. We performed the tissue freezing with already used freezing curve and we observed the actual freezing curve of that tissue. And we modified the freezing curve with several steps of calculation, polynomial regression analysis, time constant calculation, thermal response calculation and inverse calculation of chamber temperature. Result: We applied that freezing program on mesenchymal stem cell, chondrocyte, and osteoblast. The tissue temperature decreased according to the ideal freezing curve without temperature rising. We did not find any differences in survival. The reason is postulated to be that freezing material is too small and contains cellular components. We expect the significant difference in cellular viability if the freezing curve is applied on a large scale of tissues. Conclusion: This program would be helpful in finding the chamber temperature for the ideal freezing curie easily.

• Korean Journal of Veterinary Research
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• v.37 no.3
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• pp.583-593
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• 1997

Indirect fluorescent antibody test(IFAT) and enzyme-linked imuunosorbent assay (IgG-ELISA) as serological diagnostic tools were conducted to evaluate the usefulness for diagnosis of canine babesiosis infected with Babesia gibsoni in domestic various dog breeds, american pit bullterrier, military shepherd, and mongrel dogs. The results obtained from this study were abstracted as follows. The nonionic detergent Triton X-100 and absorbent bio-bead $SM_2$ were useful reagents for the preparation of pure merozoite antigen of B gibsoni to be used in ELISA. The optimum reaction in ELISA was shown when the protein concentration of ELISA antigen was measured as 625ng/ml and the conjugate concentration was diluted into 1/6000 fold. The average OD value of ELISA in sera determined with negative responses in IFAT was measured as $0.255{\pm}0.051$(490nm) and the cut - off value of OD was determined as 0.399(490nm). The serum antibodies in both of IFAT and ELISA were detected on one week after artificially infected with B gibsoni and these high antibody titers, 512X in IFAT and 1024X in ELISA, were long lasted until 15 weeks after infection. The reproducibility of reaction and stability of the antigen absorbed microtitration polystyrene plate preserved in $4^{\circ}C$ refrigerator and $-20^{\circ}C$ freezer, respectively could be lasted until 135 days after storage. The positive rates in IFAT by dog breeds were shown 8.1%(60/744 heads) in mongrel dogs, 81.3%(78/96 heads) in american pit bullterrier and 15.6%(15/96 heads) in military shepherd, while the positive rate in ELISA shown 17.6%(131/744 heads) in mongrel dogs, 83.3%(80/96 heads) in american pit bullterrier and 36.5%(35/96 heads) in military shepherd, respiectively. In the total of 936 heads surveyed with IFAT and ELISA the positive rates in IFAT and ELISA were 16.4%(153/936 heads) and 26.3%(246/936 heads), respectivily. Agreement of reactions between IFAT and ELISA was shown 82.4% in 936 dog sera. The specificity and sensitivity of ELISA reaction were 83.5% and 76.5%, respectively. From the conclusion obtained in this study it was evaluated that IFAT and ELISA were useful as highly specific, sensitive and stable serelogical tools for the diagnosis of canine babesiosis in Korea.

• Korean Journal of Weed Science
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• v.16 no.4
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• pp.309-316
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• 1996

In this study, germination characteristics and herbicidal response of green kyllinga(Kyllinga brevifolia var. leiolepsis H.) were investigated. The storage method desirable for a rapid dormancy release was to keep the seed under low temp. and wetting condition for one to two months, or high temp($40^{\circ}C$) and drying condition for three months. The dormancy of rhizome was hardly observed. The optimum temperature for germination of seed and rhizome was around $30^{\circ}C$ and 16-$20^{\circ}C$, repectively. The germination of dormancy-breaked seed was completely dependent on light. Shoot emergence ratio(%) was decreased with increase of planting depth ; for example, only 18% of rhizome segments planted in the depth of 4cm under soil surface emerged above soil surface. Flooding at earlier growth stage resulted in significant decrease in shoot emergence as well as in dry weight. The germinablity of rhizome was almost lost as a decreased in fresh weight reached to 50%. Usually, green kyllinga was sensitive to herbicides such as bentazone, bensulfuron and benfuresate etc. which were known to be effective in Cyperaceae weeds, indicating that green kyllinga can be used as a representative plant in the screening of herbicides for Cyperus weeds.