• Journal of the Korea Concrete Institute
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• v.22 no.3
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• pp.305-311
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• 2010

The industrial by-product market has increased at a geometric rate worldwide with the rapid economic growth. At present time, conventional disposal methods of industrial by-products in Korea including landfill, incineration and storage already have reached their limits. In this study, the industrial by-products such as fly ash and silicafume were used as mineral admixtures, which are commonly added to concrete mix to inhance the economic efficiency, long-term strength and durability of concrete, to determine the optimized mix proportion of high performance shotcrete. Through the series of tests (compressive strength test, accelerated chloride ion penetration test, measurement of chloride diffusion coefficient). The results of the study showed that the proposed mix proportions satisfied the requirements of domestic as well as international guidelines for shotcrete, with a higher durability than the existing shotcrete.

• Journal of Periodontal and Implant Science
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• v.33 no.4
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• pp.643-650
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• 2003

Cyclosporin-A(CsA)는 장기와 조직 이식에 따른 거부반응을 조절하기 위해 사용되는 면역억제제로, 이식의학의 발달과 더불어 사용량이 증가하고 있다. CsA의 부작용중의 하나인 치은과증식은 30-50%의 빈도로 발발하고 있다. 최근 macrolide 계열의 항생제인 azithromycin을 이용하여 이런 부작용을 억제시킨다는 임상 보고가 있어서, 이를 실험적으로 확인하고자 하였다. 이를 위해 CsA를 투여한 적이 없는 환자에서 정상 치은조직을 채취, 치은섬유아세포를 배양하였다. 우선 CsA에 대한 치은섬유아세포의 반응을 보기 위해 다양한 농도($10^{-8}-10^{-10}$g/ml)로 처치하여, 세포 증식량과 교원질 합성량을 MTT assay와 Sirol Collagen Assay를 이용하여 측정하였다. 이에 반응을 보인 조건과 세포를 대상으로 다양한 농도($10^{-8}-10^{-10}$g/ml)의 azithromycin을 CsA와 동시 처치하여 아래와 같은 결과를 얻었다. 1. CsA는 일부 치은섬유모세포의 증식을 증가시켰다. 그러나 Collagen 합성능에는 변화를 주지 않았다. 2. Azithromycin은 정상 치은섬유아세포의 증식능에 영향을 미치지 않았다. 3. Azithromycin은 CsA 에 반응을 보인 세포의 증식을 감소시켰으며, 이는 정상 수준과 유사하였다. 이상의 결과에서 azithromycin이 CsA에 의한 치은과증식 치료에 유익하다고 사료된다.

• Korean Journal of Poultry Science
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• v.15 no.3
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• pp.207-210
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• 1988

A total of 3 hybridoma clones producting menoclonal antibody (MCA) against Newcastle disease virus(NDV) was raised by cell fusion method. The MCAs did not cross react against other avian or mammalian viruses tested. However, these antibodies reacted with all strains of velogenic and lentogenic NDVs tested indicating that they are unable to discriminate the possible antigenic differences among NDVs. All. the MCAs were classified as IgG type and did not show neutralizing and hemagglutination inhibition (HAI) activity except one clone which has low HAI activity. One of these MCA raised in mouse ascites revealed the titer of $10^6$ by indirect immunofluorescent antibody (IFA) test Using the MCA, virulent NDV could easily be detected from tracheal and conjunctival smears made 2 to 3 days after experimental infection.

• Journal of Korean Tunnelling and Underground Space Association
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• v.8 no.3
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• pp.237-247
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• 2006

The use of high-performance shotcrete lining is indispensable to improve long-term durability of a tunnel and to apply the single-shell tunnelling method. Among a lot of shotcrete admixtures, pozzolan materials such as silica fume have positive effects on increasing the strength and the durability of shotcrete. It is also well known that a cement-based accelerator is much faster in setting time and more eco-friendly than conventional accelerators. This study aimed to improve the properties of wet-mix shotcrete by incorporating with Metakaolin and the calcium aluminate based accelerator. To compare Metakaolin with silica fume, mixing ratios of each material were varied as 4% and 8% of cement weight. Moreover, Metakaolin was blended with silica fume, and their binder was also set to 4% and 8% of cement weight. At each mixing condition, setting time, compressive strength, flexural strength, permeability and freezing-thawing resistance were measured. From the experiments, it was revealed Metakaolin could be a substituting material for silica fume.

• Journal of fish pathology
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• v.17 no.2
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• pp.83-90
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• 2004

The outbreak of haemorrhagic specticemia and lesions in dermis, frequently associated with keratitis have occured on rock sea bream (Oplegnathus fasciatus) reared in Jeju island. A bacterium isolated from the diseased fish identified as Pseudomonas sp. by morphologic, cultural, and biochemical tests. The bacterium was identified Pseudomonas anguilliseptica according to 16S rDNA sequence analysis. The highest growth rate of this strain was obtained at 20 to $\25^circ{C}$ although the disease occurred mostly below $16^\circ{C}$. The challenge test by ip injection revealed that this bacterium was pathogenic to rock sea bream. All experimental fish in challenged by ip injection died within 21 days but there was no death in control group. The bacterium was sensitive to Doxycycline, Chloramphenicol, Ciprofloxacin, Erythromycin, Flumequine, Nalidixic acid, Norfloxacin, and Ofloxacin.

• Nuclear Engineering and Technology
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• v.23 no.4
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• pp.374-386
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• 1991

Various factors affecting the teachability of Cs-137 in cement matrix have been investigated. Factors investigated include such as pressure curing, vibration curing, pressure leaching, the effect of the clay addition, ion-exchange resin(IRN-77) addition, and $CO_2$or air injection. Leaching experiments were conducted by the method recommended by IAEA. To analyze the experimental results, pore structure analysis of cement matrices was carried out by BET method. Cement matrices may not contact directly with underground water in real repository, since the surroundings of disposed drums are filled with backfill. Thus, the effect of backfill to the teachability has been investigated. The well-known diffusion theory was utilized to predict long term leach rate and cumulative fraction leached of Cs-137 or non-radioactive species.

• Journal of Adhesion and Interface
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• v.20 no.1
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• pp.15-22
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• 2019

In this study, polybutadiene based di-functional urethane acrylate oligomer (PB-UAO) were synthesized from polybutadiene diol and isophorone diisocyanate. And then, pressure sensitive adhesive films were prepared by mixing with synthesized oligomer, tri-functional acrylate monomer (Tris(2-acryloyloxyethyl) isocyanurate (TAOEIC) or Trimethylolpropane triacrylate (TMPTA) or Pentaerythritol triacrylate (PETA)), mono-functional acrylate monomer (Stearyl acrylate) and UV initiators. Effects of types and contents of trifunctional acrylate monomers on peel strength, tensile strength, elongation, thermal stability and water absorption property were studied. As the contents of tri-functional acrylate monomer increased, and as the molecular weight of tri-functional acrylate monomer decreased, peel strength, elongation and water absorption showed a tendency to decrease whereas tensile strength and thermal stability showed a tendency to increase.

• Journal of Nutrition and Health
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• v.29 no.9
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• pp.934-942
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• 1996

This study was performed to investigate the influence of dietary fibers on the serum lipid level and bowel function in aged rats. Fiber sources of experimental diets were made from mugwort(M), butterbur(B), apple(A), sea mustard(S) by drying and milling. Each of fiber sources was mixed into the diet at the level of 5, 15% of diet. Sprague-Dawley strain, 13 month old male rats were divided into 9 groups by randomized complete block design : C, M5, B5, A5, S5, M15, B15, A15, S15. The animals were fed ad libitum each of experimental diets for 4 weeks. Control group showed lower food intake compare to the other groups. There were no significant difference between 5% groups and 15% groups in food intake. Fecal weight, dry fecal weight and fecal water content of control group were significantly lower than those of experimental groups, and fecal water content was increased by increasing level of dietary fibber. Apple group showed the lowest values, sea mustard group showed the highest. The shorter transit time was observed in the group of higher intake of dietary fiber. At the same level of dietary fiber, transit time of sea mustard group was shorter than the other groups. With increasing age, serum triglycerides, total cholesterol were increased and HDL-cholesterol was decreased. Fiber fed groups showed lower serum TG, TC and higher HDL-c level compare to the control group. Absorption rates of calcium, magnesium and phosphorus was tend to be lower in the group fed dietary fiber sources than control group. Mucosa weight and maltase activity in the small intestine were decreased by increasing age. As intake of dietary fiber increaed, mucosa weight in the small intestine was not different but maltase activity was decreased.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.5
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• pp.557-568
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• 1995

Proteolytic properties of enzymes from the muscle and viscera of anchovy have been examined. Cathepsin L, chymotrypsin, and trypsin showed similar Km values for casein. However, they had higher Km values for myofibrillar proteins than those for casein. The $k_cat$ of cathepsin L and chymotrypsin for myofibrillar proteins were higher than that of trypsin, and also cathepsin L and chymotrypsin caused higher hydrolysis in myofibrillar proteins of anchovy and yellowtail. In the presence of sodium chloride$(0-25\%)$, proteolytic activity for myofibrillar proteins from yellowtail was higher than that for casein. Proteolytic activity was decreased with the increase of sodium chloride concentration. Cathepsin L had been less affected by NaCl concentration and temperature on the hydrolysis of myofibrillar proteins than chymotrypsin and trypsin. Cathepsin L and chymotrypsin were move responsible to the autolysis of muscle proteins from fish than trypsin.

• Proceedings of the KAIS Fall Conference
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• 2009.05a
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• pp.596-598
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• 2009

현재 상용화되어 있는 petri dish는 미생물 배지의 보관기간이 $4^{\circ}C$의 온도에서 15~50일 정도 되기 때문에 장기저장이 어렵다. 그래서 본 연구는 자체 고안된 LOP(Lab on a plate)와 petri dish에 고체배지를 제조하여 배지의 수분함량을 비교하기 위한 연구를 수행하였다. 본 연구에 사용한 배지는 Bacillus cereus 배양을 위한 MYP(Mannitol Egg Yolk Polymyxin) agar로 이용하여 제조하였으며 각각 진공포장 및 비포장하여 $4^{\circ}C$와 $25^{\circ}C$의 온도조건에서 6주 동안 매주 수분함량을 측정한 결과, LOP와 petri dish 모두 비포장 조건보다 진공포장조건의 수분보호능이 우수 하였으며 진공포장조건에서는 $25^{\circ}C$가 $4^{\circ}C$보다 상대적 수분 보호능이 좋음을 확인할 수 있었다. 또한, 비포장조건에서도 LOP가 $4^{\circ}C$와 $25^{\circ}C$ 모두 petri dish보다 수분보호능이 탁월하여 유통기간이 훨씬 더 연장될 수 있는 가능성을 보여 주어 앞으로 LOP를 이용한 장기 보관과 즉시 사용이 가능한 pre-plated media와 관련된 다양한 제품의 용기로 사용 가능할 것으로 기대된다.