• Korean Journal of Ecology and Environment
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• v.50 no.1
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• pp.29-45
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• 2017

This study explored spatiotemporal variability of water quality in correspondence with hydro-meteorological factors in the four stations of Euiam Reservoir located in the upstream region of the North-Han River from May 2012 to December 2015. Seasonal effect was apparent in the variation of water temperature, DO, electric conductivity and TSS during the study period. Stratification in the water column was observed in the near dam site every year and vanished between August and October. Increase of nitrogen nutrients was observed when inflowing discharge was low, while phosphorus increase was distinct both during the early season with increase of inflowing discharge and the period of severe draught persistent. Duration persisting high concentration of Chl-a (>$25mg\;m^{-3}$: the eutrophic status criterion, OECD, 1982) was 1~2 months of the whole year in 2014~2015, while it was almost 4 months in 2013. Water quality of Euiam Reservoir appeared to be affected basically by geomorphology and source of pollutants, such as longitudinally linked instream islands and Aggregate Island, inflowing urban stream, and wastewater treatment plant discharge. While inflowing discharge from the dams upstream and outflow pattern causing water level change seem to largely govern the variability of water quality in this particular system. In the process of spatiotemporal water quality change, factors related to climate (e.g. flood, typhoon, abruptly high rainfall, scorching heat of summer), hydrology (amount of flow and water level) might be attributed to water pulse, dilution, backflow, uptake, and sedimentation. This study showed that change of water quality in Euiam Reservoir was very dynamic and suggested that its effect could be delivered to downstream (Cheongpyeong and Paldang Reservoirs) through year-round discharge for hydropower generation.

• Korean Journal of Ecology and Environment
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• v.50 no.1
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• pp.1-15
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• 2017

Daecheong Reservoir was made by the construction of a large dam (>15 m in height) on the middle to downstream of the Geum River and the discharge systems have the watergate-spillway (WS), a hydropower penstock (HPP), and two intake towers. The purpose of this study was to investigate the limnological anomalies of turbid water reduction, green algae phenomenon, and oligotrophic state in the lower part of reservoir dam site, and compared with hydro-meteorological factors. Field surveys were conducted in two stations of near dam and the outlet of HPP with one week intervals from January to December 2000. Rainfall was closely related to the fluctuations of inflow, outflow and water level. The rainfall pattern was depended on the storm of monsoon and typhoon, and the increase of discharge and turbidity responded more strongly to the intensity than the frequency. Water temperature and DO fluctuations within the reservoir water layer were influenced by meteorological and hydrological events, and these were mainly caused by water level fluctuation based on temperature stratification, density current and discharge types. The discharges of WS and HPP induced to the flow of water bodies and the outflows of turbid water and nutrients such as nitrogen and phosphorus, respectively. Especially, when hypoxic or low-oxygen condition was present in the bottom water, the discharge through HPP has contributed significantly to the outflow of phosphorus released from the sediment into the downstream of dam. In addition, HPP effluent which be continuously operated throughout the year, was the main factor that could change to a low trophic level in the downreservoir (lacustrine zone). And water-bloom (green-tide) occurring in the lower part of reservoir was the result that the water body of upreservoir being transported and diffused toward the downreseroir, when discharging through the WS. Finally, the hydropower effluent was included the importance and dynamics that could have a temporal and spatial impacts on the physical, chemical and biological factors of the reservoir ecosystem.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.10 no.2
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• pp.164-169
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• 1999

Background and Objectives : The intracordal cysts are more increasingly diagnosed and treated due to advanced laryngeal stroboscopy and laryngeal microsurgical technique. The intracordal cysts are frequently misdiagnosed as vocal polyp or nodule The purpose of this study is to evaluate clinical features of intracordal cysts. Materials and Methods : In the present series, 83 cases of the intracordal cysts treated with laryngeal microsurgery are reported. The intracordal cysts are diagnosed preoperatively with indirect laryngoscopy, laryngeal endoscopy, laryngeal stroboscopy and confirmed with laryngeal microsurgical findings and biopsies. Results : Intracordal cysts are 83 of 1900 patients treated with laryngeal microsurgery(4.4%)-ductal cysts are 56 cases and epidermoid cysts are 27 cases. Intracordal cysts are more frequent in women, forties and the frequent site is an anterior third of the true vocal cord. With the indirect laryngoscopic examination, the ductal cysts are frequently misdiagnosed as vocal polyps or nodules but the epidermoid cysts are relatively easily diagnosed. The etiologic factors of the intracordal cysts are suspected as voice abuse and upper respiratory infection. The degree of postoperative voice satisfaction is similar to that of the vocal polyps. Conclusion : Intracordal cysts are frequently misdiagnosed as polyps or nodules, therefore preoperative stroboscopic findings and laryngeal microsurgical findings is important. An ideal treatment is to enucleate the cysts avoiding rupture of cyst and injury of lamina propria of the vocal cord.

• Journal of Life Science
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• v.15 no.3 s.70
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• pp.415-422
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• 2005

library of the mutants was prepared by transposon mutagenesis of the Mycobacterium bovis BCG. We screened this library for the resistance to an anti-tuberculosis antibiotic, PA-824. Most of the mutants resistant to the PA-824 were not able to synthesize the coenzyme $F_{420}$ which is normally produced by the wild type M. bovis BCG strains. HPLC analysis of the cellular extract showed that one of those mutants which lost the ability to synthesize $F_{420}$ still produced F0. The insertion site of the transposon in this mutant was determined by an inverse PCR and the transposon was found to be inserted in the Rv2435c open reading frame (ORF). Rv2435c ORF is predicted to encode an 80.3 kDa protein. Rv2435c protein appears to be bound to the cytoplasmic membrane, its N-terminal present in the periplasm and C-terminal in the cytoplasm. The C-terminal portion of this protein is highly homologous with the adenylyl cyclases of both prokaryotes and eukaryotes. There are 15 ORFs which have homology with the class III AC proteins in the genome of the M. tuberculosis and M. bovis. Two of those, Rv1625c and Rv2435c, are highly homologous with the mammalian ACs. We cloned the cytoplasmic domain of the Rv2435c ORF and expressed it with six histidine residues attached on its C-terminal in Escherichia coli to find out if this protein is a genuine AC. Production of that protein in E. coli was proved by purifying the histidine-tagged protein by using the Ni-NTA resin. This protein, however, failed to complement the cya mutation in E. coli, indicating that this protein lacks the AC activity. All of the further attempts to convert this protein to a functional AC by a mutagenesis with UV or hydroxylamine, or construction of several different fusion proteins with Rv1625c failed. It is, therefore, possible that Rv2435c protein might affect the conversion of F0 to $F_{420}$ not by synthesizing cAMP but by some other way.

• Proceedings of the KACD Conference
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• 2008.05a
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• pp.246-257
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• 2008

The purpose of this study was to investigate the influence of various occlusal loading sites and directions on the stress distribution of the cervical composite resin restorations of maxillary second premolar, using 3 dimensional (3D) finite element (FE) analysis. Extracted maxillary second premolar was scanned serially with Micro-CT (SkyScan1072; SkyScan, Aartselaar, Belgium). The 3D images were processed by 3D-DOCTOR (Able Software Co., Lexington, MA, USA). HyperMesh (Altair Engineering. Inc., Troy, USA) and ANSYS (Swanson Analysis Systems. Inc., Houston, USA) was used to mesh and analyze 3D FE model. Notch shaped cavity was filled with hybrid (Z100, 3M Dental Products, St. Paul, MN, USA) or flowable resin (Tetric Flow, Viva dent Ets., FL-9494-Schaan, Liechtenstein) and each restoration was simulated with adhesive layer thickness ($40{\mu}m$). A static load of 200 N was applied on the three points of the buccal incline of the palatal cusp and oriented in $20^{\circ}$ increments, from vertical (long axis of the tooth) to oblique $40^{\circ}$ direction towards the buccal. The maximum principal stresses in the occlusal and cervical cavosurface margin and vertical section of buccal surfaces of notch-shaped class V cavity were analyzed using ANSYS. As the angle of loading direction increased, tensile stress increased. Loading site had little effect on it. Under same loading condition. Tetric Flow showed relatively lower stress than Z100 overall, except both point angles. Loading direction and the elastic modulus of restorative material seem to be important factor on the cervical restoration.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.203-213
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• 2017

This study investigated the changes in yields, antioxidant compounds, and antioxidant activities among 11 adzuki bean cultivars cultivated in a paddy field with somewhat poorly drained soil. The adzuki bean cultivars were cultivated in the paddy field from 2015 to 2016 in Milyang, Gyeongsangnam, Korea. Average soil moisture content was 16.5% in 2015 and 31.0% in 2016 at the experimental site during adzuki bean cultivation. As the soil moisture content increased, most of the adzuki bean cultivars showed deceases in stem height, first setting pod node, number of pods, 100 seed weight, and yield. Chungju-pat produced the greatest yields among the 11 cultivars in 2015 and 2016, whereas Hongeon had the smallest yields. Adzuki bean yields after paddy field cultivation was lower for all cultivars than for adzuki bean yields from the same cultivars after upland field cultivation. Chungju-pat and Chilbo-pat showed the smallest decreases in yields after paddy field cultivation, whereas Hongeon and Kumsil showed the greatest yield reductions. There were no significant differences in proximate composition. Some mineral components ($P_2O_5$, Ca, and Mg) were statistically different across cultivars. Chungju-pat had the highest Ca and Mg contents, but antioxidant components (polyphenol and flavonoids) and antioxidant activities (ABTS and DPPH) were highest in Saegil and lowest in Jungbu-pat. PCA and clustering analyses, based on the growth, yield, and antioxidant component measurements, performed to identify which variables contributed the most to separating adzuki bean cultivars or to grouping cultivars with similar characteristics. These analyses showed that the antioxidant components and antioxidant activities had the most influence on grouping cultivars together. Among the 11 cultivars, Saegil was statistically different from the other cultivars, but the other 10 cultivars were not significantly different under paddy field cultivation. Soil moisture content affected adzuki bean yield and antioxidant component contents. An increase in soil moisture led to a decrease in yield, but an increase in antioxidant components. These results provide information that will improve the selection of an appropriate adzuki bean cultivar for use in paddy fields.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.3
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• pp.227-235
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• 2015

Using eddy covariance method, net ecosystem exchange (NEE) of $CO_2$ ($F_{CO_2}$), $H_2O$ (LE), and sensible heat (H) can be approximated as the sum of eddy flux ($F_c$) and storage flux term ($F_s$). Depending on strength and distribution of sink/source of scalars and magnitude of vertical turbulence mixing, the rates of changes in scalars are different with height. In order to calculate $F_s$ accurately, the differences should be considered using scalar profile measurement. However, most of flux sites for agricultural lands in Asia do not operate profile system and estimate $F_s$ using single-level scalars from eddy covariance system under the assumption that the rates of changes in scalars are constant regardless of the height. In this study, we measured $F_c$ and $F_s$ of $CO_2$, $H_2O$, and air temperature ($T_a$) using eddy covariance and profile system (i.e., the multi-level measurement system in scalars from eddy covariance measurement height to the land surface) at the Chengmicheon farmland site in Korea (CFK) in order to quantify the differences between $F_s$ calculated by single-level measurements ($F_s_{-single}$ i.e., $F_s$ from scalars measured by profile system only at eddy covariance system measurement height) and $F_s$ calculated by profile measurements and verify the errors of NEE caused by $F_s_{-single}$. The rate of change in $CO_2$, $H_2O$, and Ta were varied with height depending on the magnitudes and distribution of sink and source and the stability in the atmospheric boundary layer. Thus, $F_s_{-single}$ underestimated or overestimated $F_s$ (especially 21% underestimation in $F_s$ of $CO_2$ around sunrise and sunset (0430-0800 h and 1630-2000 h)). For $F_{CO_2}$, the errors in $F_s_{-single}$ generated 3% and 2% underestimation of $F_{CO_2}$ during nighttime (2030-0400 h) and around sunrise and sunset, respectively. In the process of nighttime correction and partitioning of $F_{CO_2}$, these differences would cause an underestimation in carbon balance at the rice paddy. In contrast, there were little differences at the errors in LE and H caused by the error in $F_s_{-single}$, irrespective of time.

• Journal of Animal Science and Technology
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• v.45 no.5
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• pp.703-710
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• 2003

The purpose of this study was to detect association between genetic variation and economic trait in the porcine heart type fatty acid-binding protein gene as a candidate gene for the traits related with growth and meat quality in pigs. The H-FABP is a 15-kDa protein expressed in several tissues with high demand for fat metabolism such as cardiac and skeletal muscle and lactating mammary gland. H-FABP is small intracellular protein involved in fatty acid transport from the plasma membrane to the site of $\beta$-oxidation and/or triacylglycerol or phospholipid synthesis. In this study, H-FABP PCR-RFLP was performed in F$_2$ population composed of 214 individuals from an intercross between Korean Native Boars and Landrace sows. PCR products from two primer sets within H-FABP gene were amplified in 850bp and 700bp. Digestion of PCR products with the restriction digestion enzymes HaeⅢ and HinfⅠ, revealed fragment length polymorphisms(RFLPs). The genotype frequencies from H-FABP/HaeⅢ was .29 for genotype DD, .53 for genotype Dd, and .15 for genotype dd, respectively. The genotype frequencies of HH, Hh, and hh from H-FABP/HinfⅠ was .38, .41 and .20, respectively, in the population. Relationships between their genotypes and economic traits were estimated. In H-FABP/HaeⅢ locus, there were specific genotypes(Dd and dd) associated with economic traits such as body weights at 3, 5, 12, and 30 week of age (p〈.05 to .001). The ‘d’ allele was associated with gaining of body weight. In H-FABP/HinfⅠ locus, Genotypes of HH and Hh associated with growth traits such as body weights at 5, 12, and 30 week of age (p〈.05 or p〈.001) and back fat thickness, body fat including abdominal and trimmed fat (p〈.001) and intramuscular fat(p〈.05) The ‘H’ allele was positively associated with gaining of body weight and fatness deposition. In conclusion, a significant association of the H-FABP gene from its genetic variation was found on body weight, intramuscular fat and backfat thickness.

• Journal of Animal Science and Technology
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• v.45 no.5
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• pp.835-840
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• 2003

Two hundreds and twenty three pork carcasses of commercial breeds were studied for comparing to technical quality characteristics of pork identified by National Pork Producers Council(NPPC) scale. pH and conductance(C) were taken in 1(pH$_1$, C$_1$), 3(pH$_3$, C$_3$), 6(pH$_6$, C$_6$) and 24hr(pHu, Cu) postmortem on 4~5th thoracic vertebrae. Visual color and CIE value were estimated in longissimus dorsi(LD) muscle in 24hr postmortem on the two sites(4~5th thoracic vertebrae and last vertebrae) using National Pork Producers Council(NPPC) scale and color difference meter. Significant differences were observed in pH$_1$, pHu, Cu, CIE L$^{*}$ value, water holding capacity(WHC) and juiciness at all scales(p〈0.05). But, pH and CIE L$^{*}$value were considerably affected by postmortem time and measuring site. NPPC scale was highly related with CIE L$^{*}$(R$^2$=0.77) and WHC(R$^2$=0.66), and moderately related with C$_{u}$(R$^2$=0.59) and pH$_{u}$(R$^2$=0.54), and poorly related with pH$_3$(R$^2$=0.32), pH$_6$(R$^2$=0.28) and C$_1$～C$_6$(R$^2$=0.03~0.18).

• Journal of Environmental Impact Assessment
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• v.29 no.1
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• pp.1-7
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• 2020

This study aims to evaluate the effect of artificial facilities constructed afterthe release of the civilian controlled zone (CCZ) in Cheorwon on the inhabitation of cranes. The study site was released from the CCZ in 2012, and several barns have been built since 2017. The average number of Red-crowned Cranes was 9.3±4.3 individuals (±Standard Deviation) in the period before the release of the CCZ from 2009 to 2012, and it decreased by ca. one third of Red-crowned Crane's average individuals were showing 3.5±0.5 individuals after release. The average number of White-naped Cranes also appeared to be decreased by ca. 90% from 63.3±24.6 to 6.0±6.0 individuals. This results suggest that the construction of greenhouses and barns after the releasing of the CCZ affected the decrease of the population of these two crane species. In the case of Red-crowned Crane, the core area tended to move away from the area where barns were built. However, the distribution range of Red-crowned Cranes did not change significantly we expected because the study area was not their favorite place since 2012 when the area was released from the CCZ. The density of the White-naped Crane was relatively high even in the area where greenhouses were built, but after 2017 when the barn was built intensively, core habitat of crane became shrink and fragmented. These results suggest that both Red-crowned Cranes and White-naped Cranes response sensitively against habitat change due to the construction of barns. Since the release of the CCZ, the construction of the greenhouse has been influenced on the distribution of cranes, but subsequently, the construction of the barn seems to have caused a bigger change in their core habitat because the passage of people to barns is more frequent than the greenhouses.