• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.2
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• pp.70-77
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• 2008

In this study, to establish countermeasure from marine casualties as a basic study fur long-term prediction of topographical change around Jinudo in the Nakdong river estuary, spatio-temporal topographical change monitoring was carried out. Also, in order to estimate the deposition variations concerning SS (Suspended Solid) flux which moved at St.S1 during neap and spring tide, respectively. From the topographical monitoring, it was found that the annual mean ground level and deposition rate were 141 mm and 0.36 mm/day and all parts except the northern part of Jinudo had the active topographical changes and a tendency to annually deposit. From vertical distribution of SS net fluxes, $SS_{LH}$ (latitudinal SS net flux) during spring tide overall flows average 28 $kg/m^2/hr$ (eastward), and $SS_{LV}$ (longitudinal SS net flux) flows average 11.1 $kg/m^2/hr$ (northward). And, $SS_{LH}$ overall flows average 4.8 $kg/m^2/hr$ (eastward), and $SS_{LV}$ flows average 1.5 $kg/m^2/hr$ (northward) during neap tide similar with spring tide. The depth averaged values of the latitudinal and longitudinal SS net fluxes during spring tide were approximately 6 times higher than those during neap tide. As result of, it was considered that topographical change of southern part of Jinudo was affected by resuspension of bottom sediments due to strong current in bottom layer during flood flow.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.2
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• pp.81-92
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• 2001

According to analyses of high-resolution seismic profiles (air gun, sparker, and SBP) and a deep-drill core(YSDP 105) in the mid-eastern Yellow Sea, stratigraphic and geoacoustic models have been established and seismo-acoustic modeling has been fulfilled using ray tracing of finite element method. Stratigraphic model reflects seismo-, litho-, and chrono-stratigraphic sequences formed under a significant influence of Quaternary glacio-eustatic sea-level fluctuations. Each sequence consists of terrestrial to very-shallow-marine coarse-grained lowstand systems tract and tidal fine-grained transgressive to highstand systems tract. Based on mean grain-size data (121 samples) of the drill core, bulk density and P-wave velocity of depositional units have been inferred and extrapolated down to a depth of the recovery using the Hamilton's regression equations. As goo-acoustic parameters, the 121 pairs of bulk density and P-wave velocity have been averaged on each unit of the stratigraphic model. As a result of computer ray-tracing simulation of the subsurface strata, we have found that there are complex ray paths and many acoustic-shadow zones owing to the presence of irregular layer boundaries and low-velocity layers.

• Korean Journal of Poultry Science
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• v.36 no.2
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• pp.165-175
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• 2009

Fatty liver-hemorrhagic syndrome (FLHS) is a common nutritional disease in commercial layers and breeders. The most important clinical sign of FLHS is a sudden drop in egg production and increased mortality which causes significant economic loss in the poultry industry. However, the current diagnostic method for FLHS is based on the gross findings at necropsy which is not helpful to reduce the economic loss because of lateness of diagnosis. Therefore, we need early diagnosis and diagnostic methods before chickens were affected by FLHS. In this study we tried to evaluate the effectiveness of clinical pathology including blood chemistry as an early diagnostic method for FLHS in commercial chickens. Profiles of blood biochemistry were compared between two flocks selected in the same commercial layer farm based on the presence of FLHS clinical sings. A flock with clinical signs of FLHS was designated as FLHS and other flock without clinical signs of FLHS as Non-FLHS. Several parameters of blood biochemistry were selected and compared between FLHS and Non-FLHS to evaluate the possibility of early diagnosis. Average concentrations of serum cholesterol, serum calcium, aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and creatine kinase (CK) were $139.4\;{\pm}\;87.2$ (mg/dL), $24.5\;{\pm}\;5.4$ (mg/dL), $153.6\;{\pm}\;23.1$ (IU/L), $1238.3\;{\pm}\;475.2$ (IU/L) and $1107.3\;{\pm}\;422.8$ (IU/L) in Non-FLHS flock, respectively, and $210.2\;{\pm}\;173.2$ (mg/dL), $25.2\;{\pm}\;4.1$ (mg/dL), $174.3\;{\pm}\;53.5$ (IU/L), $1694.9\;{\pm}\;691.3$ (IU/L) and $1104.9\;{\pm}\;472.9$ (IU/L) in FLHS flock, respectively. The activities of serum cholesterol, AST and LDH except CK, were significantly higher in FLHS than those in Non-FLHS flock (p<0.05). Some birds of FLHS flock showed 2~17 times greater than in Non-FLHS flock. For the definitive diagnosis of FLHS in the flocks tested for blood chemistry, we analyzed fat content and histological lesion score in the liver sampled from both FLHS and Non-FLHS flock. Average liver fat contents based on dry weight were $16.1\;{\pm}\;0.4$ (%) in Non-FLHS flock and were $21.6\;{\pm}\;16.0$ (%) in FLHS flock. These result confirmed that FLHS flock was definitely affected by FLHS. The above results suggest that selected parameters of blood biochemistry, particularly AST, could be useful to diagnose FLHS before significant liver damage occurred in commercial layers.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.2
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• pp.177-188
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• 1985

To clarify the characteristics and genesis of clayey terrace soils in Yeongnam area, macro-morphological features and soil profile development indexes were investigated with the sequential soils in Yeongcheon (inland region) and in Yeongil (coastal region). The results are summarized as follows; 1. According to the physiogaphy and landuse, the terrace soils were discernible to well drained yellowish red (5 YR) profile of higher terrace (Bancheon series), moderately well drained reddish yellow (7.5 YR) profile of middle terraces (Upyeong and Hwadong series), and lower terraces (Deogpyeong and Geugrag series) which were moderately well to imperfectly drained by paddy-fication. 2. The roundness and sphericity of the gravels contained in the terrace deposits were ranged around 0.543-0.546 and 0.723-0.722, respectively. The rounded to well rounded gravels were resemble to typical alluvial origins. 3. The amount of clay minerals formed in the soil horizons per 100g of parent materials were 50.8-30.7g while the rates of the clay leached were 30.1-7.4%, and the higher terrace had the more leaching rates. 4. The index of profile development of the terrace soils ranged from 37.95 to 22.01 and the index were positively correlated with relative elevations of the soils. The rates of clay leaching were positively correlated with the ratios of clay in the illuvial horizons to elluvial horizons. 5. A similarity was observed among cumulative grain size curves of the terrace soils, but the patterns of recalculated silt free cumulative grain size curve of terrace deposits in Upyeong soils in Yeongil area were abruptly different from down layer that suggest the soil to have bisequum profile.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.3
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• pp.265-271
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• 1994

Differences in carotenoid composition in the integuments of wild and cultured chinese muddy loach Misgurnus mizolepis and muddy loach Misgurnus anguillicaudatus were compared. Total carotenoid contents in the integuments of the wild and cultured chinese muddy loach were $4.76mg\%\;and\;3.43mg\%$, respectively. The important carotenoids in the integuments of the wild chinese muddy loach were lutein($30.5\%$), ${\beta}$-cryptoxanthin($24.6\%$), ${\beta}$-carotene($20.6\%$) and cynthiaxanthin($11.7\%$). In addition, zeaxanthin($4.7\%$), tunaxanthin ($4.5\%$), and a-cryptoxanthin($1.0\%$) were present in small amounts. In the integuments of the cultured chinese muddy loach, lutein($35.4\%$), ${\beta}$-cryptoxanthin($17.9\%$), cynthiaxanthin($16.0\%$) and ${\beta}$-carotene($12.7\%$) were present as important carotenoids. In addition, zeaxanthin($8.1\%$), tunaxanthin($5.0\%$), a-cryptoxanthin($0.9\%$) were found in small amounts. Total carotenoid contents in the integuments of the wild and cultured muddy loach were $4.00mg\%\;and\;2.99mg\%$, respectively. The important carotenoids in the integuments of the wild muddy loach were lutein($32.9\%$), ${\beta}$-cryptoxanthin($18.8\%$), cynthiaxanthin($17.0\%$) and ${\beta}$-carotene($15.1\%$). In addition, zeaxanthin($6.5\%$), tunaxanthin($6.0\%$) and a-cryptoxanthin($1.5\%$) were found in small amounts. In the integuments of the cultured muddy loach, lutein($51.8\%$), cynthiaxanthin($19.9\%$) and ${\beta}$-cryptoxanthin($10.8\%$) were observed as important carotenoids. In addition, ${\beta}$-carotene($5.0\%$), zeaxanthin($4.8\%$), tunaxanthin($4.5\%$) and a-cryptoxanthin($0.2\%$) were found in small amounts.

• Korean Journal of Poultry Science
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• v.35 no.3
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• pp.267-274
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• 2008

There are many kinds of anti-oxidant materials in natural plant resources. The Siberian ginseng and Eucommia are well known as anti-oxidant and medicinal plants. To investigate the effect of their anti-oxidant-like activity on telomere quantity and egg quality, diets containing Siberian ginseng leaf and Eucommia leaf at 0.5% and 1% were given Hyline Brown commercial laying hens during two periods of age: 20 to 30 wks and 60 to 70 wks. The amount of telomere in lymphocyte, liver, ovary, heart and lung was analyzed by quantitative fluorescence in situ hybridization using telomeric DNA probe. Egg weight, albumin height, Haugh unit, egg yolk color, egg shell color, egg shell thickness, egg shell weight and egg shell density were measured to analyze egg quality. The chickens consuming diets Siberian ginseng and Eucommia had higher telomeric DNA in lymphocytes than control chickens in younger layers whereas no significant differences were detected in all target cells analyzed from older layers. Egg quality was increased in younger hens with dietary supplementation as determined by egg weight, albumin height and Haugh unit but there were no effects in older hens. These results imply that dietary supplementation of Siberian ginseng and Eucommia in layers improves bio-activity and egg quality at early laying stage.

• Journal of radiological science and technology
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• v.31 no.2
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• pp.183-188
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• 2008

Aim of this study is to investigate the feasibility of 2D ion chamber array as a substitute of the water phantom system in a periodic Linac QA. For the feasibility study, a commercial ion chamber matrix was used as a substitute of the water phantom in the measurement for a routine QA beam properties. The device used in this study was the I'm RT MatriXX (Wellhofer Dosimetrie, Germany). The MatriXX consists of a 1,020 vented ion chamber array, arranged in $24{\times}24\;cm^2$ matrix. Each ion chamber has a volume of $0.08\;cm^3$, spacing of 0.762 cm. We investigated dosimetric parameters such as dose symmetry, energy ($TPR_{20,10}$), and absolute dose for comparing with the water phantom data with a Farmer-type ionization chamber (FC65G, Wellhofer Dosimetrie, Germany). For the MatriXX measurements, we used the white polystyrene phantom (${\rho}:\;1.18\;g/cm^3$) and also considered the intrinsic layer (${\rho}:\;1.06\;g/cm^3$, t: 0.36 cm) of MatriXX to be equivalent to water depth. In the preliminary study of geometrical QA using MatriXX, the rotation axis of collimator and half beam junction test were included and compared with film measurements. Regarding the dosimetrical QA, the MatriXX has shown good agreements within ${\pm}1%$ compared to the water phantom measurements. In the geometrical test, the data from MatriXX were comparable with those from the films. In conclusion, the MatriXX is a good substitute for water phantom system and film measurements. In addition, the results indicate that the MatriXX as a cost-effective novel QA tool to reduce time and personnel power.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.3
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• pp.224-232
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• 2000

Inorganic nutrient concentrations in relation to springtime physical parameters of the Yellow Sea were investigated during April 1996. Three major water masses, i.e., the Yellow Sea Warm Current Water (YSWC), Coastal Current Water (CCW) and Changjiang River Diluted Water (CRDW), prevailed in the study area. Water masses were vertically wel1 mixed throughout the study area, and nutrients were supplied adequately from bottom to surface layer. As result of ample nutrients supplied by vertical mixing together with progressed daylight condition, springtime phytoplankton blooms were observed, which was responsible for the depletion of inorganic nutrients in surface water column. Low nutrients concentration in bottom water of the central Yellow Sea (Stn. D9; nitrate: <2 ${\mu}$M, phosphate: <0.3 ${\mu}$) was associated with the entrance of YSWC which is characterized by high temperature and salinity. Influenced by runoff and vertical tidal mixing, CCW with high nutrient concentrations probably associated with China and Korea coastal waters with high nutrients concentration. For the local scale of inorganic nutrient distribution, nutrient transfers from coast to central areas were limited due to restriction imposed by tidal fronts (Stn. D6) and thus affected the horizontal nutrient profiles. Relatively high phytoplankton biomass was observed in the tidal front (Chl-${\alpha}$=12.38 ${\mu}$gL$^{-1}$) during the study period. Overall, the springtime nutrient distribution patterns in the Yellow Sea appeared to be affected by: (1) Large-scale influx of YSWC with low nutrient concentrations and CCW with high nutrient concentrations influenced by Korea and China coastal waters; (2) vertical mixing of water mass and phytoplankton distribution; and (3) local-scale tidal front as well as phytoplankton blooms alongthe tidal front.

• Korean Journal of Environmental Biology
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• v.36 no.1
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• pp.11-20
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• 2018

In planktonic ecosystems, the microplastics are considered as a potential food source for the zooplankton. To study a relationship between the zooplankton and the neustonic microplastics, a research experiment was carried out during May in the surface layers of the Yeosu coastal areas including Yeoja Bay, Gamak Bay, Yeosuhae Bay, and Botdol Sea. A neustonic zooplankton net (mesh size $300{\mu}m$; mouth area $30cm{\times}18cm$) was towed from the side of the ship in the event that it would not be affected by waves crashing by the ship at a speed of ca. 2.5 knots. All of the microplastic particles were separated from the zooplankton. The zooplankton and microplastics were appearing in a range of 61 to $763indiv.m^{-3}$ and 0.0047 to $0.3471particle\;m^{-2}$, respectively. It was noted that the Acartia omorii, Paracalanus parvus s. l., Labidocera euchaeta, A. hongi, decapod larvae, and cirriped larvae were predominantly seen in the experiment. For verifying relationships between zooplankton and environmental factors in addition to microplastics, a model redundancy analysis (RDA) was performed. The zooplankton were divided into two groups on the basis of feeding types (i.e. particle feeders, and carnivores), and the associated zooplankton larvae were also separately considered. A review of the additional environmental factors such as water temperature, salinity, turbidity, chlorophyll-${\alpha}$ concentration, diatom density, and dinoflagellate density were also contained in the analysis. The results showed that a noted zooplankton abundance had no close relation with the occurring number of microplastic particles, but rather was significantly related with other noted environmental factors such as temperature, salinity, turbidity, and chlorophyll-${\alpha}$ concentration. This fact implies that most zooplankton can feed themselves as a unit, by selecting the most likely available nutritious foods, rather than microplastics under the circumstance of food-richness areas, such what food resources are available as in the location of coastal waters.

• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.674-682
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• 1988

Total lipids from the roe, muscle and viscus of L. carinata were analyzed for lipid composition by column chromatography, thin-layer chromatography and gas-liquid chromatography. The roe lipids were characterized by a high level of wax esters (63.1%) and a low proportion of trigiycerides (9.9%). The viscus lipids also contained wax esters (32.8%) as its main component, followed by free fatty alcohols and acids (23.5%). On the other hand, the muscle lipids were found to contain a large amount of triglycerides (66.1%) with a trace of wax esters. The main fatty alcohol component of roe and viscus wax esters was C16:0 alcohol (53.0%; 61.7%), accompanied by C18:1 alcohol (10.2%) in the former and by C15:0 alcohol (8.8%) in the latter. Considerable amounts of odd-numbered fatty alcohols were found in both wax esters. On the other hand, the fatty acids of the roe and viscus wax esters contained a high percentage of monounsaturated (49.7%-56.6%) consisting of C16:1, C18:1 and C17:1 acid, and a significant amount of polyunsaturated (41.2%-32.9%), particularly C20:5${\omega}$3. The fatty acid components of triglycerides and phospholipids were different among the tissues tested, especially between roe and muscle or viscus. The fatty acid compositions of free fatty acids from the muscle and viscus were characterized by a higher level of polyunsaturated fatty acids (46.0-34.3%) compared to those of triglycerides 'in the roe, muscle and viscus (28.4%, 19.4% and 19.2%).