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Bioecological Characteristics of Coral Habitats around Moonsom, Cheju Island, Korea I. Environment Properties and Community Structures of Phytoplankton (제주도 문섬 산호서식지 주변의 생물생태학적 특성 I. 환경특성과 식물플랑크톤의 군집구조)

  • Choa, Jong-Hun;Lee, Joon-Baek
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.5 no.1
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    • pp.59-69
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    • 2000
  • Environmental factors and phytoplankton community have been bimonthly investigated in order to clarify the bioecological characteristics of coral habitats around Moonsom at the southern Cheju Island from September 1995 to July 1996. Annual mean temperature and annual mean salinity were $17.4^{\circ}C$ and 34.06 psu, respectively, showing lower temperature-higher salinity in winter and higher temperature-lower salinity in summer, which means such conditions are inadequate for coral reef formation. Nutrient concentrations represent that total nitrogen ranged from $0.07{\sim}10.08\;{\mu}M$, phosphate from $0.05{\sim}1.70\;{\mu}M$, and silicate from $3.08{\sim}21.86\;{\mu}M$. The N/P ratio showed the range of 9.59-10.60 with decreasing offshore-ward, which means the phytoplankton community could be limited by nitrogen sources. Annual mean euphotic depth was 32.0m (18.9m-48.6m) with difference according to season and reveals the close relationship with the depth of coral distribution. Chlorophyll a concentrations of phytoplankton ranged from $0.12{\sim}1.51\;{\mu}g\;L^{-1}$ and standing crops from $1.5{\times}10^3{\sim}7.0{\times}10^5\;cells\;L^{-1}$, showing higher at inshore than at offshore with a blooming in May. A total of 128 species of phytoplankton occurred in all stations, representing 99 spp. of diatoms, 26 spp. of dinoflagellates, 2 spp. of silicoflagellates and 1 sp. of blue-green algae. Diatoms are main taxa in all seasons except for occupying by dinoflagellates in summer. Among dominant species, fParalia sulcata (Ehrenberg) Cleve and Cylindrotheca closterium (Ehrenberg) Lewin & Reimann were predominant and are likely to be main food sources for coral community. Annual mean species diversity index (H') was 1.84, showing lower than around the coast line of Cheju Island.

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Myocardial Perfusion after Transmyocardial Mechanical Revascularization in Rat Heart Transplant Model, Acute Model (백서 동종이식 심장모델에서 기계적 경심근 혈관재형성의 심근 혈류 개선 효과 : 급성기 모델)

  • Shinn Sung Ho;Chung Won Sand;Kang Jung Ho;Jeon Yang-Bin
    • Journal of Chest Surgery
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    • v.38 no.7 s.252
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    • pp.468-475
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    • 2005
  • Transmyocardial revascularization (TMR) in end stage ischemic heart disease results in variable clinical responses. We investigated the acute effect of early reperfusion and the angiogenesis after formation of the transmyocardial channel in a transplanted rat heart model with acute myocardial infarction. Material and Method: In the 30 transplanted hearts we induced acute myocardial infarction by ligating the proximal left coronary artery and inserted a porous 22G intravenous cannula into the left ventricle. After ten minutes of reperfusion, we removed the cannula. At every stage, we recorded the heart rate, QRS size, and left coronary arterial blood flow using the electrocardiogram and Doppler. One week later the rats were sacrificed and evaluated for the patency of intramyocardial channels and the angiogenesis. Result: The heart rates after ligation and after cannula insertion were $239.1\pm61.7,\;235.8\pm58.0bpm$ respectively, and they were statistically significantly slower than that of before ligation, $277.6\pm40.3bpm\;(p=0.017,\;p=0.007\;respectively)$. QRS sizes before ligation, after ligation, and after cannula insertion were $3.6\pm3.3mm,\;2.8\pm3.3 mm,\;and\;2.4\pm2.2mm,$respectively, and there was no significant difference in the three groups. Doppler findings after ligation showed that average peak and mean values of coronary perfusion were significantly decreased from $2.11\pm0.17kHz,\;1.25\pm0.22kHz\;to\;0.83\pm0.15kHz,\;0.38\pm0.11kHz$(p<0.05 respectively). After insertion of the porous cannula, the average peak and mean values of coronary perfusion were $0.61\pm0.05kHz\;and\;0.33\pm0.05 kHz$ respectively, but there was no statistically significant change compared to values after ligation. In all cases except one, pathologic findings showed no patent channels in the acute stage, however, one case showed the angiogenesis. Conclusion: We confirmed that TMR in a rat heart transplant model did not show blood flow through the channel in the acute stage. However, reperfusion effect in some cases had a potential for angiogenesis.

Properties of Indium Tin Oxide Thin Films According to Oxygen Flow Rates by γ-FIB System (γ-FIB 시스템을 이용한 산소 유량 변화에 따른 산화인듐주석 박막의 특성 연구)

  • Kim, D.H.;Son, C.H.;Yun, M.S.;Lee, K.A.;Jo, T.H.;Seo, I.W.;Uhm, H.S.;Kim, I.T.;Choi, E.H.;Cho, G.S.;Kwon, G.C.
    • Journal of the Korean Vacuum Society
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    • v.21 no.6
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    • pp.333-341
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    • 2012
  • Indium Tin Oxide (ITO) thin films were prepared by RF magnetron sputtering with different flow rates of $O_2$ gas from 0 to 12 sccm. Electrical and optical properties of these films were characterized and analyzed. ITO deposited on soda lime glass and RF power was 2 kW, frequency was 13.56 MHz, and working pressure was $1.0{\times}10^{-3}$ Torr, Ar gas was fixed at 1,000 sccm. The transmittance was measured at 300~1,100 nm ranges by using Photovoltaic analysis system. Electrical properties were measured by Hall measurement system. ITO thin films surface were measured by Scanning electron microscope. Atomic force microscope surface roughness scan for ITO thin films. ITO thin films secondary electron emission coefficient(${\gamma}$) was measured by ${\gamma}$-Focused ion beam. The resistivity is about $2.4{\times}10^{-4}{\Omega}{\cdot}cm$ and the weighted average transmittance is about 84.93% at 3 sccm oxygen flow rate. Also, we investigated Work-function of ITO thin films by using Auger neutralization mechanism according to secondary electron emission coefficient(${\gamma}$) values. We confirmed secondary electron emission peak at 3 sccm oxygen flow rate.

Pervaporation Separation of Ethanol Aqueous Solution through Carbonate-type Polyurethane Membrane II. The Effect of Pendent Anionic Group (카보네이트형 폴리우레탄막을 이용한 에탄올 수용액의 투과증발분리 II. 음이온성기에 의한 영향)

  • Han, In Ki;Oh, Boo Keum;Lee, Young Moo;Noh, Si Tae
    • Applied Chemistry for Engineering
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    • v.3 no.4
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    • pp.595-604
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    • 1992
  • Carbonate-type polyurethane resins containing anionic moieties were systhesized from NCO-terminated prepolymer method. Membranes were manufactured from the polymer solution and the separation of aqueous ethanol solution was investigated. To enhance the property of urethane resin, carbonate-type polyol(PTMCG) was used. ${\alpha}^{\prime},{\alpha}^{{\prime}{\prime}}$-dimethylolpropionic acid was used as a chain extender to increase the hydrophilicily of the urethane membrane. The ionization of the pendent carboxylic groups in urethane resin was carried out using trimthylamine. To confirm the formation of anionic groups in urethane resin, IR spectra of model compounds were compared with those of urethane resins. It was confirmed that the concentration of hard segment and hydrogen bond contributed to the property of the concentration of hard segment and hydrogen bond contributed to the property of urethane resin in which the mole ratio of chain extender and polyol was from 3:1 to urethane resin in which the mole ratio of chain extender and polyol was from 3:1 to 5:1. The carbonate-type polyurethane containing pendent carboxylic grop(PU) had Tg of around-$25^{\circ}C$ and Tm, $45^{\circ}C$ measured by DSC. Transition temperatures of one containing pendent anionic group(APU) prepared from the ionization of PU shifted to $8{\sim}10^{\circ}C$ lower temperature region than those of PU. Pervaporation membrane was prepared through the casting method. N, N-dimethylformamide (DMF) were used as a solvent and hexamethylene diisocyanate(HMDl) as a crosslinking agent. Swelling degree increased with ethanol concentration in mixure and the control of the swelling degree of the membrane could be achieved by crossliking. The results of pervaporation were as follows : separation factor, 2.3~9.8 ; flux, $27{\sim}79.5g/m^2hr$. Pervaporation separation capacity could be enhanced by reducing the molecular weight of polyol from 2,000 to 1,000.

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Zooplankton Community Distribution and Food Web Structure in Small Reservoirs: Influence of Land Uses around Reservoirs and Kittoral Aquatic Plant on Zooplankton (소형저수지에서 동물플랑크톤 군집 분포와 먹이망 구조: 주변 토지 이용과 수변식생이 동물플랑크톤 군집에 미치는 영향)

  • Choi, Jong-Yun;Kim, Seong-Ki;Hong, Sung-Won;Jeong, Kwang-Seuk;La, Geung-Hwan;Joo, Gea-Jae
    • Korean Journal of Ecology and Environment
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    • v.46 no.3
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    • pp.332-342
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    • 2013
  • We collected zooplankton from May to October, 2011, with the aim of understanding the zooplankton community distribution and food web interaction between the open water and littoral (aquatic plants) zones in two small reservoirs with different land covers (Sobudang, Myeongdong). Small-sized reservoirs are more abundant in South Korea, and a total of 51 and 65 species of zooplankton were identified at the two small reservoir (Sobudang and Myeongdong), where zooplankton densities were more abundant in the littoral zone than in the open water zone. Cladocerans and copepods densities were also higher in the littoral zone, in contrast, rotifers showed higher densities in the open water zone (t-test, P/0.05). Epiphytic zooplankton dominated at the littoral zone (Lecane, Monostyla, Alona and Chydorus) because aquatic plants provided refuge spaces for attachment. Some rotifers (e.g. Brachionus, Keratella and Polyarthra) were more abundant in the open water zone because of their small size, which might help them to go unnoticed by predators. In two-way ANOVA, rotifers related to two reservoirs or habitat space (littoral zone and open water zone), but cladocerans and copepods showed a statistically significant relationship on only two reservoirs. The results of stable isotope analysis showed that zooplankton in the littoral zone tended to depend on organic matter attached to aquatic plants as a food source, which indicates the avoidance of competition of zooplankton with other macro-invertebrates (e.g. Damselfly larva, Cybister brevis and Neocardina denticulate). As a result, zooplankton community distribution is determined by not only habitat space (aquatic plant zone and open water zone) but also by food source (phytoplankton).

Quality Characteristics of Pound Cake with Addition of Cashew Nuts (캐슈를 첨가한 파운드케이크의 품질특성)

  • Choi, Soon-Nam;Chung, Nam-Yong
    • Korean journal of food and cookery science
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    • v.26 no.2
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    • pp.198-205
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    • 2010
  • In this study, the effect of added cashew nuts on the quality characteristics of pound cake were investigated. The weight and volume of the cake increased with the addition of cashew nuts concentration, whereas the dough yield and baking loss decreased. Furthermore, the hardness, penetration and, degree of retrogradation significantly decreased during storage with the addition of cashew nuts. As the cashew concentration was increased, the lightness and redness values of the crumb decreased and the yellowness values increased. In terms of sensory evaluation, when compared to the control group, the cashew nuts pound cake was superior in taste, flavor, chewiness and overall acceptability.

Quality Characteristics of Breast Meat during Post-mortem Storage of Chicken Meat (도계 후 원료육의 저장기간 동안 가슴육의 품질 특성)

  • Hwang, Yong-Joon;Park, Do-Hee;Yoon, Sung-Ho;Kim, Dong-Joon;Lee, Won-Bok;Yeon, Jae-Sung;Yi, Kwon-Jung;Kim, Soo-Ki
    • Korean Journal of Poultry Science
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    • v.42 no.4
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    • pp.347-352
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    • 2015
  • This study was first conducted to investigate the effect of post-mortem storage time of chicken meat on the quality of chicken breast, and to determine whether the current grading rule that is 'using the chicken meat within 2 day post-mortem (PM)' is appropriate or not at meat processing plants. Different methods such as freshness, lightness ($L^*$), total number of microbes, 2-thiobarbituric acid reactive substances (TBARS), shear force and cooking loss were performed. Forty samples of different PM time (0~4 day) of chicken meat were stored in the refrigerator ($3^{\circ}C$). As a result of comparing the chicken meat of 2 day and 3 day PM, torrymeter value was 6.9 and 7.0, respectively. The other values are also as follows: lightness ($L^*$) 60.22 and 60.51, total number of microbes 4.20 and $4.31log_{10}CFU/g$, TBARS value 0.056 and 0.071 mg MDA/kg, shear force 1.43 and $1.59kg/cm^2$, and cooking loss 17.24 and 15.66%, respectively. As a result, these two groups were not significantly different (P<0.05). TBARS value of the chicken meat of 4 day PM was 0.088 mg MDA/kg which is significantly higher compared to 2~3 day PM (P<0.05). Thus, the result of the study suggests that using the chicken meat within 3 day PM is also possible. If the grading rule that is 'using the chicken meat within 2 day post-mortem (PM)' is changed to 3 day PM, it will allow processing plants and distributors to more flexibly use or distribute chicken meat.

Analysis of Image Processing Characteristics in Computed Radiography System by Virtual Digital Test Pattern Method (Virtual Digital Test Pattern Method를 이용한 CR 시스템의 영상처리 특성 분석)

  • Choi, In-Seok;Kim, Jung-Min;Oh, Hye-Kyong;Kim, You-Hyun;Lee, Ki-Sung;Jeong, Hoi-Woun;Choi, Seok-Yoon
    • Journal of radiological science and technology
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    • v.33 no.2
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    • pp.97-107
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    • 2010
  • The objectives of this study is to figure out the unknown image processing methods of commercial CR system. We have implemented the processing curve of each Look up table(LUT) in REGIUS 150 CR system by using virtual digital test pattern method. The characteristic of Dry Imager was measured also. First of all, we have generated the virtual digital test pattern file with binary file editor. This file was used as an input data of CR system (REGIUS 150 CR system, KONICA MINOLTA). The DICOM files which were automatically generated output files by the CR system, were used to figure out the processing curves of each LUT modes (THX, ST, STM, LUM, BONE, LIN). The gradation curves of Dry Imager were also measured to figure out the characteristics of hard copy image. According to the results of each parameters, we identified the characteristics of image processing parameter in CR system. The processing curves which were measured by this proposed method showed the characteristics of CR system. And we found the linearity of Dry Imager in the middle area of processing curves. With these results, we found that the relationships between the curves and each parameters. The G value is related to the slope and the S value is related to the shift in x-axis of processing curves. In conclusion, the image processing method of the each commercial CR systems are different, and they are concealed. This proposed method which uses virtual digital test pattern can measure the characteristics of parameters for the image processing patterns in the CR system. We expect that the proposed method is useful to analogize the image processing means not only for this CR system, but also for the other commercial CR systems.

Long-term monitoring of heavy metal contents in paddy soils (논토양 중금속 함량의 장기변동 모니터링)

  • Kim, W.I.;Kim, M.S.;Roh, K.A.;Lee, J.S.;Yun, S.G.;Park, B.J.;Jung, G.B.;Kang, C.S.;Cho, K.R.;Ahn, M.S.;Choi, S.C.;Kim, H.J.;Kim, Y.S.;Nam, Y.K.;Choi, M.T.;Moon, Y.H.;Ahn, B.K.;Kim, H.K.;Kim, H.W.;Seo, Y.J.;Kim, J.S.;Choi, Y.J.;Lee, Y.H.;Lee, S.C.;Hwang, J.J.
    • Korean Journal of Soil Science and Fertilizer
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    • v.41 no.3
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    • pp.190-198
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    • 2008
  • There is an increasing concern over heavy metal contamination of paddy soils and the subsequent translocation of heavy metals to rice. Objective is to monitor the status and long-term trend of heavy metal contamination in paddy soils, periodically. In 2007 survey, the average concentrations of As(arsenic), Cd(cadmium), Cu(copper), Ni(nickel), Pb(lead), and Zn(zinc) in 2,010 paddy soils nationwide were 0.87, 0.08, 3.33, 1.19, 4.95 and $4.67mg\;kg^{-1}$, respectively. Few sites, which were contaminated by As in 2003 and 2007 survey and by Ni in 1999 and 2007 survey, were over the threshold level for soil contamination designated by the Soil Environmental Conservation Act in Korea. Long-term change was shown that As, Ni, and Zn were gradually increased whereas Cd and Cu were decreased. In the distribution of extractable heavy metal contents, the modes of each heavy metal content were similar with the average contents of each heavy metals. Mean value of heavy metals except copper in paddy soils was higher than median value. It means that the downward distribution of heavy metal content in paddy rice was shown against normal distribution.

Chimooite, a New Mineral from Dongnam Mine, Korea (동남광산에서 발견된 신종광물 Zn­란시아이트(치무석))

  • 최헌수;김수진
    • Journal of the Mineralogical Society of Korea
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    • v.16 no.4
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    • pp.333-339
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    • 2003
  • A new mineral, Zn analogue of rancieite (Chimooite), has been discovered at the Dongnam mine, Korea. It occurs as compact subparallel fine­grained flaky or acicular aggregates in the massive manganese oxide ores which were formed by supergene oxidation of rhodochrosite­sulfide ores in the hydrothermal veins trending NS­N25E and cutting the Pungchon limestone of the Cambrian age. The flakes of chimooite are 0.2 mm for the largest one, but usually less than 0.05 mm. The acicular crystals are elongated parallel to and flattened on (001). This mineral shows gradation to rancieite constituting its marginal part, thus both minerals are found in one and the same flake. Color is bluish black, with dull luster and brown streak in globular or massive aggregates. Cleavage is perfect in one direction. The hardness ranges from 2.5 to 4. Under reflected light it is anisotropic and bireflectant. It shows reddish brown internal reflection. Chemical analyses of different parts of both minerals suggest that rancieite and chimooite constitute a continuous solid solution series by cationic substitution. The empirical chemical formula for chimooite has been calculated following the general formula, $R_2_{x}$ M $n^{4+}$$_{9­x}$ $O_{18}$ $.$n$H_2O$ for the 7 $\AA$ phyllomanganate minerals, where x varies from 0.81 to 1.28 in so far studied samples, thus averaging to 1.0. Therefore, the formula of Zn­rancieite is close to the well­known strochiometric formula $_Mn_4^{4+}$ $O_{9}$ $.$4$H_2O$. The mineral has the formula (Z $n_{0.78}$N $a_{0.15}$C $a_{0.08}$M $g_{0.01}$ $K_{0.01}$)(M $n^{4+}$$_{3.98}$F $e^{3+}$$_{0.02}$)$_{4.00}$ $O_{9}$ $.$3.85$H_2O$, thus the ideal formula is (Zn,Ca)M $n^{4+}$$_4$ $O_{9}$ $.$3.85$H_2O$. The mineral has a hexagonal unit ceil with a=2.840 $\AA$ c=7.486 $\AA$ and a : c = 1 : 2.636. The DTA curve shows endothermic peaks at 65, 180, 690 and 102$0^{\circ}C$. The IR absorption spectrum shows absorption bands at 445, 500, 1630 and 3400 c $m^{1}$. The mineral name Chimooite has been named in honour of late Prof, Chi Moo Son of Seoul National University.ity.versity.ity.y.