• Title/Summary/Keyword: Water wall

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Analysis of Dispersion Characteristics of Circumferential Guided Waves and Application to feeder Cracking in Pressurized Heavy Water Reactor (원주 유도초음파의 분산 특성 해석 및 가압중수로 피더관 균열 탐지에의 응용)

  • Cheong, Yong-Moo;Kim, Sang-Soo;Lee, Dong-Hoon;Jung, Hyun-Kyu
    • Journal of the Korean Society for Nondestructive Testing
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    • v.24 no.4
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    • pp.307-314
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    • 2004
  • A circumferential guided wave method was developed to detect the axial crack on the bent feeder pipe. Dispersion curves of circumferential guided waves were calculated as a function of curvature of the pipe. In the case of thin plate, i.e. infinite curvature, as the frequency increases, the $S_0$ and $A_0$ mode coincide and eventually become Rayleigh wave mode. In the case of pipe, however, as the curvature increases, the lowest modes do not coincide even in the high frequencies. Based on the analysis, a rocking technique using angle beam transducer was applied to detect an axial defect in the bent region of PHWR feeder pipe. Based on the analysis of experimenal data for artificial notches, the vibration modes of each signal were identified. It was found that the notches with the depth of )0% of wall thickness can be detected with the method.

An Overturn disease of Cultured Mud Loach (Misgurnus mizolepis) (미꾸라지 (Misgurnus mizolepis)의 뒤집힘병에 관한 연구)

  • Park, Seong-U;Park, Hyeon-Tae;Choe, Seon-Nam
    • Journal of fish pathology
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    • v.17 no.1
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    • pp.21-28
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    • 2004
  • In late summer of 2001, a new disease "overturn disease" occurred among mud loach (Misgurnus mizolepis) cultured in a farm Chonbuk Province. The fish exhibited a lethargic, erratic and spiral swimming at the water surface. Affected fish showed swollen abdomen with accumulation of air bubbles in the intestinal canal. The bubbles were much larger in the anterior part than in the posterior part. Hematological and histopathological examinations were done. No significant differences were found in RBC count, Ht value and Hb concentration between the diseased and the healthy fish. Gill filaments showed proximal hyperplasia of the respiratory epithelia and fusing of the gill lamella. Hemorrhage and necrosis occurred in the intestinal epithelia and within the lamina propria, and the mucosal epithelia were separated from the muscularis. Hepatocytes underwent atrophy. In the fish experimentally tied between the annal fin and the anus by a thread to confirm accumulation of air bubbles within intestine, accumulation of air bubbles was confirmed. This disease in mud loach appeared to be induced by circulatory disturbances in the intestinal wall owing to accumulation of air bubbles in the alimentary canal after fed high protein diet throughout all culturing period.

Inhibitory Effect of BCG Cell-Wall Skeletons (BCG-CWS) Emulsified in Squalane on Tumor Growth and Metastasis in Mice

  • Yoo, Yung-Choon;Hata, Katsusuke;Lee, Kyung-Bok;Azuma, Ichiro
    • Archives of Pharmacal Research
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    • v.25 no.4
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    • pp.522-527
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    • 2002
  • The antimetastatic effect of BCG-CWS, which was emulsified in an oil-in-water form with either Drakeol 6VR mineral oil (BCG-CWS/DK) or squalane (BCG-CWS/SQA), on lung metastasis produced by highly metastatic murine tumor cells, Colon26-M3.1 carcinoma cells and B16-BL6 melanoma cells, was investigated in syngeneic mice. An intravenous (i.v.) administration of BCG-CWS (100 mg/mouse) 1 day after tumor inoculation significantly inhibited tumor metastasis of both Colon26-M3.1 carcinoma and B16-BL6 melanoma cells in experimental lung metastasis models. No differences in the antitumor activity of the two oil-based formulations (BCG-CWS/DK and BCG-CWS/SQA) were obverved. However, BCG-CWS/SQA administered through subcutaneous (s.c.) route was shown to be effective only when it was consecutively injected (3 times) after tumor inoculation. An in vivo analysis for tumor-induced angiogenesis shwed that a single i.v. administration of BCG-CWS/SQA inhibited the number of tumor-induced blood vessels and suppressed tumor growth. Furthermore, the multiple administration of BCG-CWS/SQA given at on week intervals led to a significant reduction in spontaneous lung metastasis of B16-BL6 melanoma cells in a spontaneous metastasis model. These results suggest that BCG-CWS emulsified with squalane is a potent inhibitory agent of lung metastasis, and that the anti metastatic effect of BCG-CWS is related to the suppression of tumor growth and the inhibition of tumor-induced angiogenesis.

Selection of Culture Media Applied to Grafted Cactus 'Hwangwall' for Export (수출용 접목 선인장 '황월'에 적합한 배지선발)

  • Kim, Yang Hee;Ryu, Byung Yeal
    • FLOWER RESEARCH JOURNAL
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    • v.18 no.3
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    • pp.171-178
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    • 2010
  • This work is for selecting superior media which is similar to Peat Moss that is in general use as media of Gymnocalycium mihanovichii for Export such as 'Hwang wall' but lower price. The result on growth of 7 kinds of media (Peat Moss, BM6 Culture Medium, Coco Peat, Hydro Cray, Hydro Ball, Hugato, Vermiculite) which are applied watering (overhead irrigation, sub irrigation) based on bichemical analysis including chemical, physical analysis are following. The result of bi-chemical analysis shows that Coco Peat was stabilized planting after 90 days and Hydro Ball has high water holding capacity. The experimental result of growth in grafted cactus 'Hwangwall' shows Coco Peat is similar to Peat Moss on organic matter and in case of inorganic media, Hugato, Vermiculite, Hydro Cray made satisfactory results. But, the weight of inorganic media is too light to be tied. Consequently, Coco Peat and sphagnum moss as organic media has lower price and the condition of growth is analogous to Peat Moss. On the other hands, Hydro Ball was chosen as a substitute of Peat Moss in inorganic media.

The morphological changes of the beach and dune using by periodical measurements (주기적 지형 측량을 통한 해빈과 해안사구의 지형변화: 충남 보령시 소황사구를 사례로)

  • KANG, Dong Kyun;SEO, Jong Cheol
    • Journal of The Geomorphological Association of Korea
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    • v.19 no.2
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    • pp.69-79
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    • 2012
  • The aim of this study is to analyze the mid-term changes of beach and dune morphology at Sohwang beach, Korea using by Total Station. Measurements executed 4 times during two year. Based on ArcInfo as point cloud obtained through precise measurement data by Total Station, alteration of beach and dune was analyzed at DEM, of which cell size is about 1m. Since these artificial constructions have influenced current systems of this region, the large-scale sand movements above mentioned have occurred around the jetty and the sea-wall. There occurred sedimentation in the north of the Jetty and erosion in the south of the Jetty, which is installed at the central part of object area. The direction of recent topographic development does not coincide with that of wind, and, rather, topographic changes occurred mainly at beaches and dunes due to the transformation of coastal water flow caused by artificial structure nearby. If precise measurement is conducted periodically, and long term monitoring is carried out by installing equipment measuring movement pattern of sediment around artificial structure, cause of topographic change around the object area could be discovered.

Bioconversion of Lignocellulosic Materials with the Contribution of a Multifunctional GH78 Glycoside Hydrolase from Xylaria polymorpha to Release Aromatic Fragments and Carbohydrates

  • Liers, Christiane;Ullrich, Rene;Kellner, Harald;Chi, Do Huu;Quynh, Dang Thu;Luyen, Nguyen Dinh;Huong, Le Mai;Hofrichter, Martin;Nghi, Do Huu
    • Journal of Microbiology and Biotechnology
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    • v.31 no.10
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    • pp.1438-1445
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    • 2021
  • A bifunctional glycoside hydrolase GH78 from the ascomycete Xylaria polymorpha (XpoGH78) possesses catalytic versatility towards both glycosides and esters, which may be advantageous for the efficient degradation of the plant cell-wall complex that contains both diverse sugar residues and esterified structures. The contribution of XpoGH78 to the conversion of lignocellulosic materials without any chemical pretreatment to release the water-soluble aromatic fragments, carbohydrates, and methanol was studied. The disintegrating effect of enzymatic lignocellulose treatment can be significantly improved by using different kinds of hydrolases and phenoloxidases. The considerable changes in low (3 kDa), medium (30 kDa), and high (> 200 kDa) aromatic fragments were observed after the treatment with XpoGH78 alone or with this potent cocktail. Synergistic conversion of rape straw also resulted in a release of 17.3 mg of total carbohydrates (e.g., arabinose, galactose, glucose, mannose, xylose) per gram of substrate after incubating for 72 h. Moreover, the treatment of rape straw with XpoGH78 led to a marginal methanol release of approximately 17 ㎍/g and improved to 270 ㎍/g by cooperation with the above accessory enzymes. In the case of beech wood conversion, the combined catalysis by XpoGH78 and laccase caused an effect comparable with that of fungal strain X. polymorpha in woody cultures concerning the liberation of aromatic lignocellulose fragments.

Image Quality and Radiation Dose of High-Pitch Dual-Source Spiral Cardiothoracic Computed Tomography in Young Children with Congenital Heart Disease: Comparison of Non-Electrocardiography Synchronization and Prospective Electrocardiography Triggering

  • Goo, Hyun Woo
    • Korean Journal of Radiology
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    • v.19 no.6
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    • pp.1031-1041
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    • 2018
  • Objective: To compare image quality and radiation dose of high-pitch dual-source spiral cardiothoracic computed tomography (CT) between non-electrocardiography (ECG)-synchronized and prospectively ECG-triggered data acquisitions in young children with congenital heart disease. Materials and Methods: Eighty-six children (${\leq}3$ years) with congenital heart disease who underwent high-pitch dual-source spiral cardiothoracic CT were included in this retrospective study. They were divided into two groups (n = 43 for each; group 1 with non-ECG-synchronization and group 2 with prospective ECG triggering). Patient-related parameters, radiation dose, and image quality were compared between the two groups. Results: There were no significant differences in patient-related parameters including age, cross-sectional area, body density, and water-equivalent area between the two groups (p > 0.05). Regarding radiation dose parameters, only volume CT dose index values were significantly different between group 1 ($1.13{\pm}0.09mGy$) and group 2 ($1.07{\pm}0.12mGy$, p < 0.02). Among image quality parameters, significantly higher image noise ($3.8{\pm}0.7$ Hounsfield units [HU] vs. $3.3{\pm}0.6HU$, p < 0.001), significantly lower signal-to-noise ratio ($105.0{\pm}28.9$ vs. $134.1{\pm}44.4$, p = 0.001) and contrast-to-noise ratio ($84.5{\pm}27.2$ vs. $110.1{\pm}43.2$, p = 0.002), and significantly less diaphragm motion artifacts ($3.8{\pm}0.5$ vs. $3.7{\pm}0.4$, p < 0.04) were found in group 1 compared with group 2. Image quality grades of cardiac structures, coronary arteries, ascending aorta, pulmonary trunk, lung markings, and chest wall showed no significant difference between groups (p > 0.05). Conclusion: In high-pitch dual-source spiral pediatric cardiothoracic CT, additional ECG triggering does not substantially reduce motion artifacts in young children with congenital heart disease.

An Experimental Study on Flow Characteristics in the Open Annular Flume (환형수조에서 흐름특성에 관한 실험적 연구)

  • Choi, In Ho;Kim, Jong Woo
    • Journal of Wetlands Research
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    • v.21 no.3
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    • pp.207-214
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    • 2019
  • This study investigated the flow characteristics in an annular flume with a free water surface using the Acoustic Doppler Velocimeter(ADV) in the laboratory. The flow was driven by the rotation of the inner cylinder in a way designed not to interfere with flocculation of cohesive sediments. The effect of the inner cylinder for the longitudinal velocities showed highest near the moving boundary and decreased towards the outer wall. At the lower longitudinal velocity, there was a peak in turbulent kinetic energy near the bed, whereas it moved upward to with increasing of the velocity. The longitudinal velocities estimated using the power law were in good agreement with the measured values than the values predicted by the log-law with roughness lengths. The average friction velocities evaluated by Reynolds shear stress were smaller than the values calculated using the log-law and power law when increasing the longitudinal velocity.

Effect on Viability of Microencapsulated Lactobacillus rhamnosus with the Whey Protein-pullulan Gels in Simulated Gastrointestinal Conditions and Properties of Gels

  • Zhang, Minghao;Cai, Dan;Song, Qiumei;Wang, Yu;Sun, Haiyue;Piao, Chunhong;Yu, Hansong;Liu, Junmei;Liu, Jingsheng;Wang, Yuhua
    • Food Science of Animal Resources
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    • v.39 no.3
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    • pp.459-473
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    • 2019
  • Lactobacillus rhamnosus GG (LGG) has low resistance to low pH and bile salt in the gastrointestinal juice. In this study, the gel made from whey protein concentrate (WPC) and pullulan (PUL) was used as the wall material to prepare the microencapsulation for LGG protection. The gelation process was optimized and the properties of gel were also determined. The results showed the optimal gel was made from 10% WPC and 8.0% PUL at pH 7.5, which could get the best protective effect; the viable counts of LGG were 6.61 Log CFU/g after exposure to simulated gastric juice (SGJ) and 9.40 Log CFU/g to simulated intestinal juice (SIJ) for 4 h. Sodium dodecyl sulphite polyacrylamide gel electrophoresis (SDS-PAGE) confirmed that the WPC-PUL gel had low solubility in SGJ, but dissolved well in SIJ, which suggested that the gel can protect LGG under SGJ condition and release probiotics in the SIJ. Moreover, when the gel has highest hardness and water-holding capacity, the viable counts of LGG were not the best, suggesting the relationship between the protection and the properties of the gel was non-linear.

Crystal Structure of LysB4, an Endolysin from Bacillus cereus-Targeting Bacteriophage B4

  • Hong, Seokho;Son, Bokyung;Ryu, Sangryeol;Ha, Nam-Chul
    • Molecules and Cells
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    • v.42 no.1
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    • pp.79-86
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    • 2019
  • Endolysins are bacteriophage-derived enzymes that hydrolyze the peptidoglycan of host bacteria. Endolysins are considered to be promising tools for the control of pathogenic bacteria. LysB4 is an endolysin produced by Bacillus cereus-infecting bacteriophage B4, and consists of an N-terminal enzymatic active domain (EAD) and a C-terminal cell wall binding domain (CBD). LysB4 was discovered for the first time as an L-alanoyl-D-glutamate endopeptidase with the ability to breakdown the peptidoglycan among B. cereus-infecting phages. To understand the activity of LysB4 at the molecular level, this study determined the X-ray crystal structure of the LysB4 EAD, using the full-length LysB4 endolysin. The LysB4 EAD has an active site that is typical of LAS-type enzymes, where $Zn^{2+}$ is tetrahedrally coordinated by three amino acid residues and one water molecule. Mutational studies identified essential residues that are involved in lytic activity. Based on the structural and biochemical information about LysB4, we suggest a ligand-docking model and a putative endopeptidase mechanism for the LysB4 EAD. These suggestions add insight into the molecular mechanism of the endolysin LysB4 in B. cereus-infecting phages.