• Journal of the Korean GEO-environmental Society
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• v.13 no.1
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• pp.53-61
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• 2012

In this study, the research on MC anchor has been developed as composite type has done. MC anchor exerts bearing pressure on pre-bored hole where the end fixing device is expanded. Therefore, the uplift capacity is to be increased and it has the characteristics that the anchor body is not eliminated from the ground even if the grouting is not carried out properly. Furthermore, it reduces the loss of tension and raises the construction availability by inserting the reinforced bar as well as the anchor cable, while it can improve the long-term stability because the nail is expected to play the role when the loss of the anchor cable is occurred in a long-term. However, because the resistance mechanism of the compound anchor such as MC anchor is different from friction anchor, the estimation method of the uplift capacity by the frictional force of the ground and the grout is not proper. Particularly, in domestic cases, the problem to overestimate or underestimate the uplift capacity is expected because the design method considering the soil characteristics about the compound anchor has not been developed. Therefore, in this study, in order to evaluate the characteristics of MC anchor and a kind of compound anchor, we measured the uplift, the tension and the creep by nine anchors tests in shale ground that the fluctuation of the strength is great. In addition, we analyzed the test result comparing to the result of the general friction anchor and evaluated the characteristics of MC anchor movement to gather the results. As a result of the test, we found the effect that the uplift capacity is increased in shale ground comparing to the general friction anchor.

• Journal of the Microelectronics and Packaging Society
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• v.11 no.3 s.32
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• pp.37-45
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• 2004

Electroless Ni(P) has been widely used for under bump metallization (UBM) of flip chip and surface finish layer in microelectronic packaging because of its excellent solderability, corrosion resistance, uniformity, selective deposition without photo-lithography, and also good diffusion barrier. However, the brittle fracture at solder joints and the spatting of intermetallic compound (IMC) associated with electroless Ni(P) are critical issues for its successful applications. In the present study, the mechanism of IMC spatting and microstructure change of the Ni(P) film were investigated with varying P content in the Ni(P) film (4.6,9, and $13 wt.\%$P). A reaction between Sn penetrated through the channels among $Ni_3Sn_4$ IMCs and the P-rich layer ($Ni_3P$) of the Ni(P) film formed a $Ni_3SnP$ layer. Thickening of the $Ni_3SnP$ layer led to $Ni_3Sn_4$ spatting. After $Ni_3Sn_4$ spatting, the Ni(P) film directly contacted the molten solder and the $Ni_3P$ phase further transformed into a $Ni_2P$ phase. During the crystallization process, some cracks formed in the Ni(P) film to release tensile stress accumulated from volume shrinkage of the film.

• Journal of Chest Surgery
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• v.23 no.2
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• pp.222-230
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• 1990

Protamine, a polycationic peptide extracted from fish, has been widely used for the reversal of anticoagulant action of heparin. However it may cause untoward circulatory side effects including hypotension and bradyarrhythmia. Nowadays, histamine and prostacyclin are regarded as one of the causative agents in the underlying mechanism of hemodynamic changes. To certify the possible role of histamine and prostacyclin, we observed simultaneous changes of the hemodynamic status, plasma concentration of thromboxane B, and circulating platelet count before and after intravenous injection of protamine. Experimental dogs, weighing 12-14kg, were divided into 2 groups; group A animals [n=10], were pretreated with indomethacin[2.5mg/kg] and group B animals[n=10] were pretreated with chlorpheniramine[0.5mg/kg] Heparin[3mg/kg] and protamine [3mg/kg] were administered sequentially in both groups. The results were as follows ; 1. The mean systemic arterial pressure was maintained well in groups A, whereas in group B it decreased from 165\ulcorner18mmHg to 138\ulcorner30mmHg[p<0.01] and 151\ulcorner21 mmHg[p<0.05] at 1 minute and 2 minutes after protamine injection. The mean pulmonary arterial pressure was not changed significantly in group A, whereas in group B it increased from 852 mmHg to 11\ulcorner3 mmHg[p<0.05], 11\ulcorner3 mmHg[p<0.05] and 10\ulcorner3 mmHg[p<0.05] at 1 minute, 3 minutes and 5 minutes after protamine injection. 2 The thromboxane B2 was not changed significantly in group A, whereas in group B it increased from 399\ulcorner401 \ulcornerg/ml to 744\ulcorner615 \ulcornerg/ml[p<0.05] and 814\ulcorner1070 \ulcornerg/ml [p<0.0 5] at 1 minute and 3 minutes after protamine injection without concomitant changes of pulmonary vascular resistance and pulmonary capillary wedge pressure. 3. The number of circulating platelet was not changed in group A, whereas in group B it decreased from 207100\ulcorner103600/\ulcornerl to 159700\ulcorner90900/\ulcornerl [p<0.05] at 1 minute after protamine injection, Although thromboxane B2 and platelet count were changed significantly after protamine injection, they did not cause the remarkable hemodynamic changes. Considering the above results, hemodynamic changes may be caused mainly by prostacyclin rather than thromboxane or platelet. Therefore, the pretreatment with cyclooxygenase inhibitor would be beneficial to prevent circulatory adverse effects of protamine for the patients undergoing cardiac surgery.

• Membrane Journal
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• v.23 no.3
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• pp.211-219
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• 2013

Effect of water back-flushing period (FT) was investigated in hybrid water treatment process of carbon ultrafiltration and polypropylene (PP) beads coated with photocatalyst, and membrane effect was studied by comparing the previous studies with carbon microfiltration or alumina ultrafiltration, microfiltration membranes. FT 6 min was the most effective to control initial membrane fouling and optimal condition because the membrane fouling resistance was low until initial 60 min and the maximum total permeate volume was acquired at this FT. The turbidity treatment efficiency was high beyond 98.6%, and did not depend on FT, which was same with the previous result of carbon or alumina microfiltration. The organic matters treatment efficiency was the highest value of 98.2% at FT 6 min, which was almost same trend with the previous result of alumina microfiltration. Then the organic matters treatment efficiency of carbon microfiltration was the minimum at no back-flushing (NBF) and increased as decreasing FT, but that of alumina ultrafiltration was the maximum at NBF and also increased as decreasing FT. Therefore it means that water back-flushing effect on the organic matters treatment efficiency had a different mechanism depending on pore size in spite of the same material membranes.

• Microbiology and Biotechnology Letters
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• v.41 no.1
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• pp.88-95
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• 2013

Candida biofilms are self-organized microbial communities growing on the surfaces of host tissues and medical devices. These biofilms have been displaying increasing resistance against conventional antifungal agents. The roots of Scutellaria baicalensis have been widely used for medicinal purpose throughout East Asia. The aim of the present study was to evaluate the effect of S. baicalensis aqueous extract upon the preformed biofilms of 10 clinical C. albicans isolates, and assess the mechanism of the antibiofilm activity. Its effect on preformed biofilm was judged using an XTT reduction assay and the metabolic activity of all tested strains were reduced ($57.7{\pm}17.3$%) at MIC values. The S. baicalenis extract inhibited (1, 3)-${\beta}$-D-glucan synthase activity. The effect of S. baicalensis on the morphology of C. albicans was related to the changes in growth caused by inhibiting glucan synthesis; most cells were round and swollen, and cell walls were densely stained or ruptured. The anticandidal activity was fungicidal, and the extract also arrested C. albicans cells at $G_0/G_1$. The data suggest that S. baicalensis has multiple fatal effects on target fungi, which ultimately result in cell wall disruption and killing by inhibiting (1, 3)-${\beta}$-D-glucan synthesis. Therefore, S. baicalensis holds great promise for use in treating and eliminating biofilm-associated Candida infections.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.36 no.1
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• pp.45-53
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• 2000

To analyze the photodegradation mechanism of materials for fisheries facilities which stand for considerable time immediately under or even partly above the water surface, such as cage collar, cage net, stationary fishing gear, egc. after 900 hours exposure, weathering experiments on 3 kinds of netting twines like dyed polyethylene(PE) and nylon, and non-treated high strength PE(Hi-PE) were carried out by using xenon light source. The results obtained are as follows : It was observed by scanning electron micrograph(SEM) that a good protection by pigments was obtained in PE and nylon specimen, while crack was rapidly progressed at the surface of Hi-PE one owing to etching by UVR. There was a little increase in density resulting from reorientation of polymer chain, chain scission, etc. in Hi-PE specimen. A wide angle X-ray diffraction showed that 3 kinds of specimens had no fundamental changes in polymer crystalline structure considering each 2$\theta$ of diffraction peak. Remaining tenacity of netting twines was in order of PE, nylon, and Hi-PE after having been exposed to the effect of 900 hours. PE and nylon treated with stuffs were shown to be more resilient than non-treated Hi-PE as confirmed by SEM.

• Korean Journal of Weed Science
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• v.18 no.3
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• pp.237-245
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• 1998

The transgenic tobacco (Nicotiana tabacum cv. Xanthi) plants containing Bacillus subtilis protoporphyrinogen oxidase gene with cauliflower mosaic virus 35S promoter have recently been generated by using Agrobacterium-mediated gene transformation. The nontransgenic and the transgenic tobacco plants were compared with respect to responses to diphenyl ether herbicide oxyfluorfen and under various environmental conditions. Both cellular leakage and lipid peroxidation caused by oxyfluorfen were found to be less in the transgenic than in the nontransgenic plants. Growth responses of the transgenic plants under various temperature, light, and water conditions were almost the same as those of the nontransgenic plants, although the transgenic plants exhibited slightly more retarded growth under low light or saturated water condition. These results revealed that the transgenic tobacco plants containing B. subtilis protoporphyrinogen oxidase gene under cauliflower mosaic virus 35S promoter were relatively resistant to oxyfluorfen and exhibited normal growth pattern. Possible mechanism of resistance to oxyfluorfen in the transgenic plants is also discussed.

• Journal of Korean Tunnelling and Underground Space Association
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• v.21 no.1
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• pp.1-29
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• 2019

Related to the previous paper on the typical crack pattern of tunnel lining with NATM, the characteristic defects in reinforced cement concrete lining of NATM tunnel have analyzed with the precise inspection with safety and diagnosis (PISD) by KISTEC. Depending on the reinforcing materials, steel rebar, steel fiber, and glass fiber have been implemented to reinforcing lining in various NATM tunnel constructions. Reinforcing lining with rebar are prevailed on NATM tunnel to countermeasure the weak geological circumstances, to pursuit the economical tunnel sections, and to resist the risk of tunnel deterioration. By the special act on the safety control of public facilities, the reinforced NATM tunnels for more than 1 km length are scrutinized closely to characterize defects; crack, reinforcement exposure, and lack of lining. Crack resistance by reinforcing is shown in comparison with the normalized crack to the length of tunnel. Typical exposed reinforcements in lining have exemplified with various sections. The lack of lining due to the mal-construction, spalling, fire, earthquake and leaching has been analyzed. The cause and mechanism with the field inspections and other studies has also been verified. Detailed cases are selected by the above concerns as well as the basic information from FMS (Facilities Management System). Likewise the previous paper, this study provides specialized defects in reinforced lining of NATM and it can be widely used in spreading the essential technics and reporting skills. Furthermore, it would be advised and amended for the detail guideline of Safety Diagnosis and PISD (tunnel).

• Korean Journal of Food Science and Technology
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• v.54 no.1
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• pp.28-34
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• 2022

Glioblastoma is the most common primary malignant brain tumor and has an extremely poor prognosis. Glioblastoma stem cells (GSCs) contribute to tumor initiation, recurrence, and resistance to therapy, and are thus a key therapeutic target. The peel of Citrus unshiu Markovich has been used in traditional medicine in East Asia to treat various diseases. In this study, we investigated the anticancer activity and molecular mechanism of the chloroform extract of this natural product (CECU) in U87MG GSCs. The results show that CECU inhibited the proliferation, tumorsphere formation, and migration of U87MG GSCs by causing cell cycle arrest at the G0/G1 phase and apoptosis. In addition, CECU downregulated key cancer stemness regulators, including CD133, Oct4, Nanog, integrin α6, ALDH1A1, and STAT3 signaling in U87MG GSCs. Furthermore, CECU significantly suppressed in vivo tumor growth of U87MG GSCs in a chorioallantoic membrane model. Therefore, CECU can be utilized as a natural medicine for the prevention and treatment of glioblastoma.

• Journal of Korea Entertainment Industry Association
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• v.13 no.2
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• pp.253-259
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• 2019

Prostate cancer(PrCa) is a leading cause of cancer-related death in man. Medicinal plants are exploited for many drugs to treat various ailments. The drugs derived from the plants promote health, augmented the resistance of the body against disease. Pueraia lobata(wild) Ohwi(P. Lobata), kudzu, which is a twining perennial woody herb native to China, Korea, Japan, India, and the United States. Plants such as Moringa oleifera, have hypoglycemic properties and other beneficial properties. The objective of the study was to analyze the effects of kadzu and moringa, natural plant products on antioxidant activity and proliferation of the hormone-sensitive prostate cancer LNCaP cells. MTT assay, flow cytometry analysis were employed to investigate the anticancer mechanism and DPPH assay was determined to the antioxidant activity to scavenge free radicals in extract of these. All two extracts showed significantly antioxidant activity at 10 and 50mg/ml of concentration. kadzu and moringa reduced LNCaP cell viability in a dose dependent manner. Specially moringa extract was more potent cytotoxic than kadzu extract. Statistical analyses revealed kadzu and moringa exhibited significantly higher (P < 0.05) cytotoxicity and antioxidant activity in LNCaP. The finding of this study provides a scientific basis for using kadzu and moringa in future development of chemotherapeutic drugs against hormone-sensitive prostate cancer.