• Carbon letters
• /
• v.14 no.1
• /
• pp.14-21
• /
• 2013

Physically and chemically activated carbons (ACs) exhibited high adsorption capacities for organic and inorganic pollutants compared with other adsorbents due to their expanded surface areas and wide pore volume distribution. In this work, seven steam-ACs with different burn-off have been prepared from cotton stalks. The textural properties of these sorbents were determined using nitrogen adsorption at $-196^{\circ}C$. The chemistry of the surface of the present sorbents was characterized by determining the surface functional C-O groups using Fourier transform infrared spectroscopy, surface pH, $pH_{pzc}$, and Boehm's acid-base neutralization method. The textural properties and the morphology of the sorbent surface depend on the percentage of burn-off. The surface acidity and surface basicity are related to the burn-off percentage. A theoretical model was developed to find a mathematical expression that relates the % burn-off to ash content, surface area, and mean pore radius. Also, the chemistry of the carbon surface is related to the % burn-off. A mathematical expression was proposed where % burn-off was taken as an independent factor and the other variable as a dependent factor. This expression allows the choice of the value of % burn-off with required steam-AC properties.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2004.05a
• /
• pp.184-187
• /
• 2004

There are many factors that generate the early deterioration of the concrete structure. As the one of the representative factors, we can think an invasion of the water, air and so on. The water and air invade in inside void along the capillarity and they become the cause that the durability like corrosion of layer department due to freezing and thawing, inside steel frame corrosion, and so on blacks. Therefore with covering permeability covering waterproofing material of fluid condition in outer wall, intercepting the deterioration factor due to the infiltration of water from outside and for salt damage of concrete layer department, freezing damage and neutralization, it needs to improve durability of structure. This study separately examined physical and chemical specific of quality liguid siliceous of waterproofing material. Therefore as this applys the construction site, it improves the durability of concrete structure. Further this presents the application plan from the construction market against the new material.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2003.11a
• /
• pp.63-67
• /
• 2003

There are many factors that generate the early deterioration of the concrete structure. As the one of the representative factors, we can think an invasion of the water, air and so on. The water and air invade in inside void along the capillarity and they become the cause that the durability like corrosion of layer department due to freezing and thawing, inside steel frame corrosion, and so on blacks. Therefore with covering permeability covering waterproofing material of fluid condition in outer wall, intercepting the deterioration factor due to the infiltration of water from outside and for salt damage of concrete layer department, freezing damage and neutralization, it needs, to improve durability of structure. This study separately examined physical and chemical specific of quality liguid siliceous of waterproofing material. Therefore as this applys the construction site, it improves the durability of concrete structure. Further this presents the application plan from the construction market against the new material.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2003.05a
• /
• pp.63-67
• /
• 2003

There are many factors that generate the early deterioration of the concrete structure. As the one of the representative factors, we can think an invasion of the water, air and so on. The water and air invade in inside void along the capillarity and they become the cause that the durability like corrosion of layer department due to freezing and thawing, inside steel frame corrosion, and so on blacks. Therefore with covering permeability covering waterproofing material of fluid condition in outer wall, intercepting the deterioration factor due to the infiltration of water from outside and for salt damage of concrete layer department, freezing damage and neutralization, it needs to improve durability of structure. This study separately examined physical and chemical specific of quality liquid siliceous of waterproofing material. Therefore as this applys the construction site, it improves the durability of concrete structure. Further this presents the application plan from the construction market against the new material.

• Journal of Microbiology and Biotechnology
• /
• v.16 no.10
• /
• pp.1513-1517
• /
• 2006

One single lactic acid producing bacterium, isolated from kimchi, inhibited the growth and adherence of Helicobacter pylori to the human gastric epithelial cell line MKN-45. This isolate was identified as Lactobacillus plantarum and termed L. plantarum strain PL9011. The adherence of H pylori, in the presence of live or nonviable L. plantarum strain PL9011 (10-fold CFU), decreased to 14-20%. The spent culture supernatant of L. plantarum strain PL9011 resulted in the eradication of H pylori. This activity remained stable following neutralization and heat treatment, but not following pepsin treatment, thereby suggesting small peptides as the inhibitory factor. L. plantarum strain PL9011 did not produce any harmful metabolites or enzymes. The results obtained in this study suggest that the L. plantarum strain PL9011 may be a potential novel probiotic for the stomach.

• IMMUNE NETWORK
• /
• v.1 no.3
• /
• pp.250-259
• /
• 2001

To determine if initial infection with Mycobacterium tuberculosis changes the balance of cytokines between T cells and macrophages, we evaluated interferon (IFN)-${\gamma}$), interleukin-12 (IL)-12, and tumor necrosis factor (TNF)-${\alpha}$ productions by peripheral blood mononuclear cells (PBMC) from 15 untreated active pulmonary tuberculosis (TB) patients and 12 healthy tuberculin reactors (HTR). Freshly isolated PBMC were stimulated with Triton X-100 solubilized protein (TSP), 30-kDa or purified protein derivatives (PPD) antigen for 6, 18 and 96 hours. IL-12 p40 production by antigen-stimulated PBMC from TB patients was significantly decreased compared with that in HTR. In addition, IFN-${\gamma}$ production was significantly depressed in TB patients than that in HTR at a 96-hr stimulation. However, TNF-${\alpha}$ production was significantly higher in antigen-stimulated PBMC from TB than that of HTR. A pronounced increase in IFN-${\gamma}$ protein followed neutralization of IL-10 in early TB patients. However, neutralization of TNF-${\alpha}$ did not significantly alter IFN-${\gamma}$ induction in PBMC from TB patients. There were no significantly differences in the cytokine productions among three proteins, TSP, 30-kDa or PPD antigen. These results indicate that development of TB may be strongly associated with dysregulated productions of IL-12, IFN-${\gamma}$ and TNF-${\alpha}$, during the initial immune responses to M. tuberculosis. Further understanding of operative cytokine networks during human immune cell responses to protein antigens of M. tuberculosis may improve strategies for vaccine development.

• Korean Journal of Microbiology
• /
• v.41 no.4
• /
• pp.275-280
• /
• 2005

Anthrax is an infectious disease caused by the gram-positive bacterium, Bacillus anthracis. Anthrax toxin is a tripartite toxin comprising of protective antigen (PA), lethal factor (LF) and edema factor (EF). PA is the receptor-binding component, which facilitates the entry of LF or EF onto the cytosol. LF is a zinc-dependent metalloprotease, which is a critical virulence factor in cytotoxicity of infected animals. Therefore, it is of interest to develop its potent inhibitors for the neutralization of anthrax toxin. The first step to identify the inhibitors is the development of a rapid, sensitive, and simple assay method with a high-throughput ability. Much efforts have been concentrated on the preparation of powerful assays and on the screening of inhibitors using these system. In the present study, we have tried to construct anthrax lethal factor in yeast expression system to prepare cell-based high-throughput assay system. Here, we have shown the results covering the construction of a new vector system, subcloning of LF gene, and the expression of target gene. Our results are first trial to express LF gene in eukaryote and provide the basic steps in design of cell-based assay system.

• Molecules and Cells
• /
• v.20 no.2
• /
• pp.263-270
• /
• 2005

Transactivation of EGF-receptor (EGFR) by G-protein coupled receptors (GPCRs) is emerging as an important pathway in cell proliferation, which plays a crucial role in the development of atherosclerotic lesion. Angiotensin II (Ang II) has been identified to have a major role in the formation of atherosclerotic lesions, although the underlying mechanisms remain largely unclear. We hypothesize that Ang II promotes the proliferation and migration of smooth muscle cells through the release of heparin-binding epidermal growth factor like growth factor (HB-EGF), transactivation of EGFR and activation of Akt and Erk 1/2, with matrix metalloproteases (MMPs) playing a dispensable role. Primary rat aortic smooth muscle cells were used in this study. Smooth muscle cells rendered quiescent by serum deprivation for 12 h were treated with Ang II (100 nM) in the presence of either GM6001 ($20{\mu}M$), a specific inhibitor of MMPs or AG1478 ($10{\mu}M$), an inhibitor of EGFR. The levels of phosphorylation of EGFR, Akt and Erk 1/2 were assessed in the cell lysates. Inhibition of MMPs by GM6001 significantly attenuated Ang II-stimulated phosphorylation of EGFR, suggesting that MMPs may be involved in the transactivation of EGFR by Ang II receptor. Furthermore Ang II-stimulated proliferation and migration of smooth muscle cells were significantly blunted by inhibiting MMPs and EGFR and applying HB-EGF neutralization antibody, indicating that MMPs, HB-EGF and EGFR activation is necessary for Ang-II stimulated migration and proliferation of smooth muscle cells. Our results suggest that inhibition of MMPs may represent one of the strategies to counter the mitogenic and motogenic effects of Ang II on smooth muscle cells and thereby prevent the formation and development of atherosclerotic lesions.

• Environmental Engineering Research
• /
• v.14 no.4
• /
• pp.220-225
• /
• 2009

The water quality in eutrophic lakes is affected by serious problems, such as abnormal increasing of Cyanobacteria. The purpose of this study was to investigate the possibility of a modified flotation system using a hybrid technique formed by chemical compounds and an electrostatic bridge. Therefore, experiments using the hybrid technique were performed to measure the zeta potential value on the phytoplankton surface and the removal efficiencies of phytoplankton, ammonia nitrogen, nitrate nitrogen and phosphoric acid. The results were as follows: Firstly, the zeta potential of M.aeruginosa was observed to approach charge neutralization due to adhesion of magnesium hydroxide precipitate on the phytoplankton surface in the pH range 10.5 to 11. Secondly, the concentration of chlorophyll-a decreased from about 150 to 20${\mu}g$g/L, with a maximum removal efficiency of 84% due to coagulation with pH values higher than 10. Thirdly, the N$H_4$-N concentration was observed to decrease from 0.62 to 0.54mg-N/L (13%), and the P$O_4$-P concentration, which is a limiting factor to the formation of algae blooms, decreased from 0.27 to 0.02mg-P/L (92%). These findings suggest that the modified flotation system can be applied for the purification of the raw water of numerous lakes containing high phytoplankton populations and elevated pH.

• Journal of fish pathology
• /
• v.27 no.2
• /
• pp.85-89
• /
• 2014

Water temperature is a key environmental factor controlling the epizootics of viral diseases in fish. High water temperature is associated with the rapid spread of rock bream iridovirus (RBIV) disease and with high mortality of RBIV infected fish. Although protection of fish against iridoviral disease by active immunization has been reported, little information is available concerning whether fish survived from an epizootic of iridoviral disease can naturally acquire resistance against the viral disease. In the present study, we have demonstrated that juvenile rock bream, which survived from a natural epizootic of RBIV, acquired resistance against recurrence or reinfection of RBIV, and this resistance was established during the subsequent low water temperature period. Furthermore, the possible involvement of the adaptive humoral immune response in the resistance of the juvenile rock bream was suggested by in vivo neutralization experiment.