• Title/Summary/Keyword: Water-blocking

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A Three-Dimensional Modeling Study of Lake Paldang for Spatial and Temporal Distributions of Temperature, Current, Residence Time, and Spreading Pattern of Incoming Flows (팔당호 수온, 유속, 체류시간의 시.공간적 분포 및 유입지류 흐름에 관한 3차원 모델 연구)

  • Na, Eun-Hye;Park, Seok-Soon
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.9
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    • pp.978-988
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    • 2005
  • A three-dimensional dynamic model was applied to Lake Paldang, Han River in this study. The model was calibrated and verified using the data measured under different ambient conditions. The model results were in reasonable agreements with the field measurements in both calibration and verification. Utilizing the validated model, we analyzed the spatial and temporal distributions of temperature, current, residence time, and spreading pattern of incoming flows within the lake. Relatively low velocity and high temperature were computed at the surface layer in the southern region of the Sonae island. The longest residence time within the lake was predicted in the southern region of the Sonae island and the downstream region of the South Branch. This can be attributed to the fact that the back currents caused by the dam blocking occur mainly in these regions. Vertical thermal profiles indicated that the thermal stratifications would be occurred feebly in early summer and winter. During early spring and fall, it appeared that there would be no discernible differences at the vertical temperature profiles in the entire lake. The vertical overturns, however, do not occur during these periods due to an influence of high discharge flows from the dam. During midsummer monsoon season with high precipitation, the thermal stratification was disrupted by high incoming flow rates and discharges from the dam and very short residence time was resulted in the entire lake. In this circulation patterns, the plume of the Kyoungan stream with smallest flow rate and higher water temperature tends to travel downstream horizontally along the eastern shore of the south island and vertically at the top surface layer. The model results suggest that the Paldang lake should be a highly hydrodynamic water body with large spatial and temporal variations.

Bioequivalence of Carvelol Tablet to Dilatrend Tablet (Carvedilol 25 mg) (딜라트렌 정(카르베딜롤 25 mg)에 대한 카베롤 정의 생물학적 동등성)

  • Cho, Hea-Young;Lee, Moon-Seok;Park, Soon-Cheol;Lim, Dong-Koo;Moon, Jai-Dong;Lee, Yong-Bok
    • Journal of Pharmaceutical Investigation
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    • v.31 no.4
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    • pp.289-295
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    • 2001
  • Carvedilol is an antihypertensive and antianginal compound that combines nonselective beta-adrenoceptor blocking and vasodilation properties and is devoid of intrinsic sympathomimetic activity. The purpose of the present study was to evaluate the bioequivalence of two carvedilol tablets, $Dilatrend^{TM}$ (Chong Kun Dang Pharmaceutical Co., Ltd.) and $Carvelol^{TM}$ (Dae Won Pharmaceutical Co., Ltd.), according to the prior and revised guidelines of Korea Food and Drug Administration (KFDA). The carvedilol release from the two carvedilol tablets in vitro was tested using KP VII Apparatus II method with various different kinds of dissolution media (pH 1.2, 4.0, 6.8 buffer solution, water and blend of PSB80 into water). Eighteen normal male volunteers, $24.22{\pm}1.86$ years in age and $64.81{\pm}4.56\;kg$ in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After one tablet containing 25 mg of carvedilol was orally administered, blood was taken at predetermined time intervals and the concentrations of carvedilol in serum were determined using HPLC method with fluorescence detector. The dissolution profiles of two carvedilol tablets were very similar at all dissolution media. Besides, the pharmacokinetic parameters such as $AUC_t$, $C_{max}$ and $T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using non-transformed and logarithmically transformed $AUC_t$ and $C_{max}$. The results showed that the differences in $AUC_t$, $C_{max}$ and $T_{max}$ between two tablets based on the $Dilatrend^{TM}$ were 2.23%, -2.00% and 0.00%, respectively. Minimum detectable differences $({\Delta})$ at ${\alpha}=0.05$ and $1-{\beta}=0.8$ were less than 20% (e.g., 13.55% and 17.61% for $AUC_t$ and $C_{max}$, respectively). The powers $(l-{\beta})$ at ${\alpha}=0.05$, ${\Delta}=0.2$ for $AUC_t$ and $C_{max}$ were 98.08% and 88.81%, respectively. The 90% confidence intervals were within ${\pm}20%$ (e.g., $-5.69{\sim}10.16$ and $-12.30{\sim}8.30$ for $AUC_t$ and $C_{max}$, respectively). There were no sequence effect between two tablets in logarithmically transformed $AUC_t$ and $C_{max}$. The 90% confidence intervals using logarithmically transformed were within the acceptance range of log(0.8) to log(1.25) (e.g., $0.95{\sim}1.11$ and $0.89{\sim}1.09$ for $AUC_t$ and $C_{max}$, respectively). Two parameters met the criteria of prior and revised KFDA guideline for bioequivalence, indicating that $Carvelol^{TM}$ tablet is bioequivalent to $Dilatrend^{TM}$ tablet.

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Impact of Sluice Gates at Stream Mouth on Fish Community (하구의 배수갑문 설치 유무가 어류군집에 미치는 영향)

  • Kim, Jun-Wan;Kim, Kyu-Jin;Choi, Beom-Myeong;Yoon, Ju-Duk;Park, Bae-Kyung;Kim, Jong-Hak;Jang, Min-Ho
    • Korean Journal of Ecology and Environment
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    • v.55 no.1
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    • pp.49-59
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    • 2022
  • Total of 325 estuaries in Korea were surveyed to analyze the effect of presence of sluice gate on the estuary environment and fish community from 2016 to 2018. Fish community in closed and open estuaries showed differences generally, and the relative abundance (RA) of primary freshwater species in the closed and migratory species in the open estuaries were high. The result of classifying species by habitat characteristics in closed and open estuaries showed similar tendencies at the estuaries of south sea and west sea. The relative abundances of primary freshwater species in the closed estuaries at the estuaries of south sea and west sea were the highest, but estuarine and migratory species were high in both closed and open estuaries at the estuaries of east sea. Primary freshwater species showed higher abundances in the closed estuaries with reduced salinity due to blocking of seawater since they are not resistant to salt. However, primary freshwater species in open estuaries at east sea was higher than that of the closed estuaries, which is considered to be the result of reflecting the characteristics (tide, sand bar, etc.) of the east sea. Korea Estuary Fish Assessment Index (KEFAI) was showed to be higher at open estuaries than closed in all sea areas (T-test, P<0.001), the highest KEFAI was observed in closed estuaries at south sea, and open estuaries in east sea. Fish community of closed and open estuaries in each sea areas showed statistically significant differences (PERMANOVA, East, Pseudo-F=3.0198, P=0.002; South, Pseudo-F=22.00, P=0.001; West, Pseudo-F=14.067, P=0.001). Fish assemblage similarity by sea areas showed a significant differences on fish community in closed and open estuaries at east sea, south sea, and west sea (SIMPER, Group dissimilarity, 85.85%, 88.36%, and 88.05%). This study provided information on the characteristics and distribution of fish community according to the types of estuaries. The results of this study can be used as a reference for establishing appropriate management plans according to the sea areas and type in the management and restoration of estuaries for future.

Effect of High Pressure Processing on Freshness of Meat Products (육류가공품의 고압처리가 신선도에 미치는 영향 평가)

  • Hwang, Seong-Hee
    • Journal of Food Hygiene and Safety
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    • v.33 no.4
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    • pp.272-279
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    • 2018
  • The high pressure processing (HPP) is a technology which can preserve the quality of foods, such as the fresh taste, incense, texture, vitamin content, and so on, by minimizing the heating process. It does so by applying an instantaneous and uniform pressure that is the same as the water pressure that is 60 km deep in the sea. HPP is a technology that can inhibit food poisoning and spoilage caused by microorganisms and is currently an actively studied area. In this study, we investigated the effects of a high pressure treatment (0, 4, 6 min) on sliced ham, which is a typical meat product, at 600 MP a were tested for their effect on freshness. Moisture contents varied from 48 to 69%, salinity varied from 1.07 to 1.11%, and the pH decreased from 6.4~6.5 to 6.1~5.15. However, there was no difference between the control and treatment groups. General bacteria stored at $20^{\circ}C$ after hyper-pressure treatment were found to have no significant microorganisms in all groups until 4 weeks. but exceeded $10^5$ in control group and HPP 6 min treatment group from 5 weeks, At week 7, it was found to exceed $10^6$. The results indicate it was not possible to ingest food in the 4-and 6 minute treatment groups. Coliform was not observed in all groups despite observing for a total of 7 weeks at $20^{\circ}C$ weight test. VBN, a method used to determine the protein freshness of meat, showed a VBN value of less than 1 mg% until the fourth week and a value of 1 to 2 mg% after 5 weeks. The TBA was used as an index of the degree of fat acidosis in the meat tissues. The results showed it was below 0.18 mgMA / kg until the end of 7 weeks; this value was within the range for fresh meat, and there was no difference in treatment group. In this experiment, deformation of the packaging material did not occur and no swelling occurred due to the generation of gas. It is believed that the basic preservation effect was achieved only by blocking with the air due to the close contact of the packaging material.

Effects of Fouling and Scaling on the Retention of Explosives in Surface Water by NF-the Role of Cake Enhanced Concentration Polarisation (지표수 조건의 나노여과공정에서 파울링 및 스케일링이 화약류 물질 잔류에 미치는 영향 연구 - 케익층 형성 및 농도분극 영향 분석)

  • Heo, Jiyong;Han, Jonghun;Lee, Heebum;Lee, Jongyeol;Her, Namguk
    • Journal of the Korean GEO-environmental Society
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    • v.16 no.4
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    • pp.13-22
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    • 2015
  • The combined impact of Dissolved Organic Matter (DOM) fouling and inorganic ($CaSO_4,Ca_3(PO_4)_2$) scaling on the retention of TNT (2, 4, 6-Trinitrotoluene), RDX (Hexahydro-1, 3, 5-trinitro-1, 3, 5-triazine) and HMX (1, 3, 5, 7-Tetranitro-1, 3, 5, 7-tetrazocane) explosive contaminants by nano-filtration membrane were studied, since organic fouling and salt scaling are the major limitations for membrane filtration. Results reported here indicate that DOM fouling layer with a humic acid does not necessarily lead to an immediate loss of permeate flux but can result in a severe impact on the flux loss when both humic acid and inorganic scaltants were presented simultaneously. The $Ca_3(PO_4)_2$ mixed with humic acid showd most sever flux loss (42%) compared to that of only humic acid presence (8%). It could be a result that the scaling formation of the NF membrane was dominated by cake layer formation of DOM and it was along with pore blocking by the formation of crystals inside the porous active matrix of the NF membrane. In addition, these results indicated that the membrane selectivity of the explosives retention trended correlated with respect to increasing explosives size (listed by MW) based on greater steric interactions and followed the order (MW, g $mol^{-1}$; removal, %): HMX (296.15; 83%) ${\gg}$ RDX (222.12; 49%) ≋ TNT (227.13; 32%). Because the scaling and fouling layer could lead to a additional cake-enhanced concentration polarisation effect, the retention of explosives with the presence of humic acid in the feed solution and inorganic scaling formation on top of an organic fouling layer do not differ substantially retention from that of pure DI feed and NaCl solution.

Inhibition of Cancer Cell Migration by Compounds from Garlic Extracts (마늘추출물에 의한 암세포의 이동 저하)

  • Kim, Eun-Kyoung;Yun, Sung-Ji;Ha, Jung-Min;Jin, In-Hye;Kim, Young-Whan;Kim, Sun-Gun;Park, Da-Jung;Choi, Young-Whan;Yun, Sik;Kim, Chi-Dae;Bae, Sun-Sik
    • Journal of Life Science
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    • v.21 no.6
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    • pp.767-774
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    • 2011
  • Cell migration plays a fundamental role in cancer cell invasion and metastasis as well as in many physiological responses. Here, we screened four different sources of garlic - water extract of normal and black garlic, as well as dried normal and black garlic - for the identification of anti-invasive and anti-metastatic activity on cancer cells. Inhibition of cancer cell migration was observed in the hexane extract of dried-garlic. Inhibitory activity was further purified to near homogeneity by thin layer chromatography and named $\b{i}$nhibitor of $\b{c}$ancer $\b{m}$etastasis from garlic #27 (ICMG-27). ICMG-27 completely blocked insulin-like growth factor-1 (IGF-1)-induced OVCAR-3 cell migration at 6 ${\mu}g/ml$. ICMG-27 completely blocked IGF-1-induced OVCAR-3 and NIH-3T3 cell migration whereas IGF-1-induced mouse embryonic fibroblast (MEF) cell migration was not affected byICMG-27. ICMG-27 inhibited all the tested IGF-1-induced cancer cell migration such as OVCAR-3, SKOV-3, and MDA-MB-231 cells. Finally, ICMG-27 could inhibit IGF-1-, lysophosphatidic acid (LPA)-, sphingosine-1-phosphate (S1P)-, leukotriene B4 (LTB4)-, and angiotensin II (AngII)-induced OVCAR-3 cell migration. These results indicate that ICMG-27 inhibits cancer cell migration by blocking essential steps in many agonists-induced cancer cell migrations. Unveiling an anti-invasive mechanism of ICMG-27 on cancer cells will provide a basis for cancer therapy.

An Historical and Cultural Analysis on the Eastern and Western Moat (동·서양 해자(垓字)의 역사와 문화적 해석)

  • Jung, Yong-Jo;Sim, Woo-Kyung
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.29 no.1
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    • pp.105-120
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    • 2011
  • A moat is a pond or waterway paved on the outside of a fortress that is one of the facilities to prevent enemy from approaching the fortress wall or classify it as the boundary space, moats had existed in Europe, Asia and the America from ancient times to medieval times. however it is has been disappeared in modem society. In addition, a moat is a great value in historical and cultural sense such as offering a variety of cultural activities and habitats for animals, but unfortunately there is little consideration of its restoration plan. This research is aimed to investigate historical and cultural meaning and significance of moats which had been existing from ancient times to medieval times in the Eastern and Western. For this purpose, this research analyzed concepts and functions in consideration with times and ideological backgrounds of moats in Korea, China, and Japan. Results were as follows: 1. Moats in Korea existed not only in the castle towns of Goguryeo but also in ancient castle towns of Baekje and Silla. Natural moats and artificial moats existed around castles that were built to prevent and disconnect accessibility of enemies In Goryeo Dynasty and Chosun Dynasty, moats were also used as a defensive function. 2. A moat was generally installed by digging in the ground deep and wide at regular intervals from the ramparts, A moat was installed not only around a castle but also in its interiors. Moats outside castles played an important role in stomping the ground hard besides enhancing its defensive power. In addition, water bodies around a facility often discouraged people's access and walls or fences segregated space physically, but a moat with its open space had an alert and defensive means while pertaining its visual characteristics. 3. The moat found at Nagan Eupseong rumor has it that a village officials' strength was extremely tough due to strong energy of the blue dragon[Dongcheon] in Pungsujiri aspects, so such worries could be eliminated by letting the stream of the blue dragon flow in the form of 'S'. 4. The rampart of the Forbidden City of China is 7.9 meters high, and 3,428 meters long in circumference. It was built with 15 layers of bricks which were tamped down after being mixed with glutinous rice and earth, so it is really solid. The moat of the Forbidden City is 52 meters in width and 6 meters in depth, which surrounds the rampart of the Forbidden City, possibly blocking off enemies' approach. 5. Japan moats functioned as waterways due to their location in cities, further, with the arrangement of leisure facilities nearby, such as boating, fishing from boats, and restaurants, it helped relieve city dwellers' stress and functions as a lively city space. 6. Korean moats are smaller in scale than those of the Forbidden City of China, and Edo, and Osaka castles in Japan, Moats were mostly installed to protect royal palaces or castles in the Eastern Asia whereas moats were installed to protect kings, lords, or properties of wealthy people in the west.