• Journal of Bio-Environment Control
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• v.16 no.1
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• pp.67-71
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• 2007

This study was conducted to find out the influence of cultivation season for fresh parsley in modified atmosphere storage. As the qualities of fresh parsley grown in different seasons; autumn, winter, summer were compared, the chlorophyll and vitamin C showed the highest content in autumn and winter cultivation, respectively, but the firmness was the highest in summer cultivation treatment. These fresh parsleys grown in different seasons packaged with 0.04mm ceramic film and stored at $0^{\circ}C$. The shelf life of these parsleys were 84 days in winter cultivation treatment, while parsleys cultivated in autumn and summer were able to be stored for 77 days and 56 days, respectively. The fresh weight loss of parsley was much more higher in summer than in both autumn and winter cultivation treatments. The carbon dioxide and ethylene contents in packages in summer were more than twice as high in autumn and winter cultivation treatment. There were not different between autumn and winter cultivation treatment in the two kinds of gas contents. This result should be caused by higher field heat that increased a respiration remarkably during the early storage. The highest field heat produced by summer cultivation resulted in remarkable decreases of firmness, chlorophyll and vitamin C during MA storage. As the results, the fresh parsley showed highest storability in winter cultivation treatment. The field heat of fresh parsley should be eliminated just after harvest for a long term storage.

• Journal of Periodontal and Implant Science
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• v.36 no.4
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• pp.797-808
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• 2006

Objective : The purpose of this study was to evaluate the physicochemical properties and cytocompatibility of microporous, spherical biphasic calcium phosphate(BCP) ceramics with a 60/40 $hydroxyapatite/{\beta}$ -tricalcium phosphate weight ratio for application as a bone graft substitute. Materials and Methods : Microporous, spherical BCP granules(MGSB) were prepared and their basic characteristics were compared with commercially available BCP(MBCP; Biomatlante, France) and deproteinized bovine bone mineral(Bio-Oss; GBistlich-Pharma, Switzerland, BBP; Oscotec. Korea), Their physicochemical properties were evaluated by scanning electron microscopy, X-ray diffractometry, Fourier-transform infrared spectroscopy, inductively coupled plasma atomic emission spectrometer, and Brunauer-Emmett-Teller method. Cell viability and proliferation of MC3T3-El cells on different graft materials were evaluated. Results : MGSB granules showed a chemical composition and crystallinity similar with those in MBCP, they showed surface structure characteristic of three dimensionally, well-interconnected micropores. The results of MTT assay showed increases in cell viablity with increasing incubation times. At 4d of incubation, MGSB, MBCP and BBP showed similar values in optical density, but Bio-Oss exhibited significantly lower optical density compared to other bone substitutes(p <0,05). MGSB showed significantly greater cell number compared to other bone substitutes at 3, 5, and 7d of incubation(p <0,05), which were similar with those in polystyrene culture plates. Conclusion: These results indicated the suitable physicochemical properties of MGSB granules for application as an effective bone graft substitute. which provided compatible environment for osteoblast cell growth. However, further detailed studies are needed to confirm its biological effects on bone formation in vivo.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.10
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• pp.2985-2989
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• 2009

An experiment was conducted to examine the effects of ceramic sheet on concentration of students studies. To demonstrate the improvement in the concentration of study, we obtained functional magnetic resonance imaging (fMRI), which has superior time resolution and measures brain noninvasively by using intrinsic contrast agent. As a result of Brainwave measurement, we could verify the blood flow's activate in the nearby frontal lobe related to memory process and noticeable ratio change in absolute alpha wave and beta wave after the analysis of Brainwave measurement. fMRI ascertains the physiological function of the brain and is being used to prevent the trouble medically that can be caused before and after the operation. For the visibility of cranial nerve network, many researches will be carried out to develope the product which is related to brain like concentration of study.

• Journal of the Korean Chemical Society
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• v.56 no.5
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• pp.571-576
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• 2012

A sol-gel derived carbon composite electrodes (CCEs) were fabricated by mixing horseradish peroxidase (HRP), sol of tetraethoxysilane (TESO), and graphite powder. The HRP solution was added to the sol solution of TEOS, and then graphite powder was added to this mixture. The resulting carbon ceramic network effectively encapsulated HRP and shows a catalytic reduction starting at -0.2 V for $H_2O_2$. The optimum conditions for $H_2O_2$determination have been characterized with respect to the enzyme loading ratio and pH. The linear range and detection limit of $H_2O_2$ detection were from 0.2 mM to 2.2 mM and 0.035 mM, respectively. The common electroactive interferences such as ascorbic acid, acetaminophene, and uric acid were not affected upon the response to $H_2O_2$ at the HRP biosensor due to low detection potential.

• Resources Recycling
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• v.27 no.6
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• pp.38-43
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• 2018

In this study, using electro-refining process and methane gas reduction, we performed studying the recovery of tin with high purity from waste tin oxide had used as a electrode rod of ceramic furnace which occurred during glass production process. We recovered the crude tin of 99% purity from a methane gas reduction process and controlled a little amount of impurities. When the electrolytic refining condition was a current density of $60A/dm^2$ and the sulfuric acid concentration of 0.75 mol, 96.8% of recovered tin (99.979% of purity) were recovered during the electrolytic refining. We confirmed that toxic impurities such as Pb, Sb included in electrode rod. could be controlled.

• IMMUNE NETWORK
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• v.24 no.3
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• pp.19.1-19.15
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• 2024

The influenza virus poses a global health burden. Currently, an annual vaccine is used to reduce influenza virus-associated morbidity and mortality. Most influenza vaccines have been developed to elicit neutralizing Abs against influenza virus. These Abs primarily target immunodominant epitopes derived from hemagglutinin (HA) or neuraminidase (NA) of the influenza virus incorporated in vaccines. However, HA and NA are highly variable proteins that are prone to antigenic changes, which can reduce vaccine efficacy. Therefore, it is essential to develop universal vaccines that target immunodominant epitopes derived from conserved regions of the influenza virus, enabling cross-protection among different virus variants. The internal proteins of the influenza virus serve as ideal targets for universal vaccines. These internal proteins are presented by MHC class I molecules on Ag-presenting cells, such as dendritic cells, and recognized by CD8 T cells, which elicit CD8 T cell responses, reducing the likelihood of disease and influenza viral spread by inducing virus-infected cell apoptosis. In this review, we highlight the importance of CD8 T cell-mediated immunity against influenza viruses and that of viral epitopes for developing CD8 T cell-based influenza vaccines.

• Journal of Bio-Environment Control
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• v.19 no.1
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• pp.49-54
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• 2010

The study was conducted to compare the postharvest physiology and storability of fresh cut paprika fruits classified by normal, blossom end rot(BER), and misshapen (or knots) fruit. Some disordered paprika fruits that were produced frequently during high temperature season in highland, were sorted out to non-marketable products. These fruits are mostly wasted, but some of them may be used for fresh cut. The respiration rate of fresh cut paprika fruits was lower and ethylene production rate was higher in normal fruits than in disordered fruits, but there was no significant difference. The fresh-cut paprika fruits were stored in MAP conditions at $4^{\circ}C$, $9^{\circ}C$ and room temperature in 25 ${\mu}m$ and 50 ${\mu}m$ thickness ceramic film packaging. The fresh weight of fresh cut paprika fruits decreased below to 1.1% regardless of fruit types, but the fresh weight loss increased in thinner packaging materials and lower storage temperatures. There were not significant different carbon dioxide and oxygen contents in MAP of all fruit types, while $4^{\circ}C$ storage temperature treatment and 25 ${\mu}m$ thickness ceramic film treatment had lower carbon dioxide and higher oxygen contents. Moreover, the carbon dioxide and oxygen contents were changed rapidly at 9 days in $4^{\circ}C$ storage and at 6 days in $9^{\circ}C$ storage when the visual quality of fresh cut decreased dramatically. The ethylene concentration of packages was below 7 ${\mu}l{\cdot}l^{-1}$ in all treatments during storage, while the treatments of thinner packaging material and lower storage temperature showed lower ethylene concentration. The fresh cut of disordered fruits showed less visual quality than normal fruit treatment in both $4^{\circ}C$ and $9^{\circ}C$ storage temperatures, but there was no significant difference. The value of $4^{\circ}C$ treatment that measured 12 days in storage was higher than $9^{\circ}C$ treatment that measured 9 days in storage. The results suggest that the disordered fruits may be used to fresh cut product without any concerns that they will decreased the value of commodities more quickly than the fresh cut made of marketable paprika fruits. As the fresh cut paprika fruits stored in MAP condition, the more effective storage temperature is $4^{\circ}C$ that may have induced chilling injury a whole fruit of the paprika.

• Journal of Bio-Environment Control
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• v.18 no.2
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• pp.166-170
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• 2009

The temperature fluctuations was investigated in cold distribution chain of radish sprout, typical of commercial practice. Although the temperature of distribution chain was maintained below 5$^{\circ}C$ in precooling and packaging steps, and 10$^{\circ}C$ in transporting, temperature of loading step increased up to 18$^{\circ}C$ at market. Based on this investigation, the simulated cold distribution conditions were consisted of precooling and packaging step; 5$^{\circ}C$ for 12 hours and transporting and loading steps; 5$^{\circ}C$, 10$^{\circ}C$, 20$^{\circ}C$ and $^{\circ}C$ for 6 hours, and storage and market steps; 5$^{\circ}C$ and 10$^{\circ}C$ for 17 days. The radish sprouts were cultivated at 25$^{\circ}C$ and dark condition for S days and placed in light condition for greening. They were packaged by 25 ${\mu}m$ ceramic film after precooling for 6 hours in 5$^{\circ}C$. The fresh weight loss and visual quality of radish sprout decreased with the increase of the temperature in transporting and loading steps. The carbon dioxide content of packages increased, but the oxygen content decreased rapidly in 1day after storage, as the temperature of transporting and loading steps increased. The ethylene content in packages increased fastest in higher temperature of transporting and loading steps treatment, and showed highest in 5$^{\circ}C$-30$^{\circ}C$-10$^{\circ}C$ treatment (temperature of precooling and packaging steps for 12 hours - temperature of transporting and loading steps for 6 hours - temperature of storage step for 14 days) followed by 5$^{\circ}C$-20$^{\circ}C$-10$^{\circ}C$ treatment. The high temperature of transporting and loading steps resulted in deterioration qualities and atmosphere conditions in packages of sprout. These results suggested that the temperature fluctuation in distribution should influence the shelf-life of radish sprouts, even thought the periods of fluctuation was just 6 hours.

• Journal of Wetlands Research
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• v.18 no.2
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• pp.194-200
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• 2016

The impervious surface rate increased by urbanization causes various problems on the environment such as water cycle distortion, heat island effect, and non-point pollutant discharges. The Low Impact Development (LID) techniques are significantly considered as an important tool for stormwater management in urban areas and development projects. The main mechanisms of LID technologies are hydrological and environmental pollution reduction among soils, media, microorganisms, and plants. Especially, the media provides important functions on permeability and retention rate of stormwater runoff in LID facilities. Therefore, this research was performed to assess the pollutant removal efficiency for different types of media such as zeolite, wood chip, bottom ash, and bio-ceramic. All media show high pollutant removal efficiency of more than 60% for particulate materials and heavy metals. Double layered media is more effective in reducing heavy metals by providing diverse sizes of micro-pores and macro-pores compared to the single layered media. The results recommend the use of different sizes of media application is more cost-effective in LID than a single size of media. Furthermore, soluble proportion of total heavy metal in the stormwater is an important component in proper media selection and arrangement.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.6
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• pp.741-755
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• 1999

As a material of metal-ceramic prosthesis, nickel as a form of Ni-Cr alloy has been used for many dental prostheses in many cases. However, several problems in use of the alloy have been revealed (ex : tissue stimulation, skin allergy, hypersensitivity, cytotoxicity and carcinogenecity). Little is known about nickel with respect to the relationship between Ni-prosthesis and gaining of Ni-resistance in oral microorganisms. The present study was undertaken to check wheather use of Ni-prosthesis leads to occurrence of Ni-resistant microorganisms. So this study may suggest the possible relationships between the oral microorganisms and nickel-resistance in oral environment. Bacteria were isolated from the gingival crevicular fluid on the pateints wearing Ni-Cr prosthesis. The isolated bacteria were tested for their Ni-resistance in nickel containing media at different concentration from 3mM to 110mM. E. coli HB101 was used as control. The Ni-resistant bacteria were isolated and biochemically identified. The Ni-resistant bacteria were tested several bio-chemical, molecular-biological tests. Performed tests were ; measuring the growth curve, antibiotic test, growth ability test in liquid media, isolation of the chromosome and plasmid, digestion of DNA by restriction enzyme, electrophoresis of chromosome and plasmid DNA, identification of Ni-resistant genes by the DNA hybridization. The results were as follows: 1) The bacteria isolated from gingival crevicular fluid on the patients wearing Ni-Cr alloy pros-thesis showed nickel-resistance. 2) The isolated microorganisms grew at nickel containing media of high concentrations (60mM-110mM). 3) Based on the biochemical tests, the isolated microorganisms were identified as Enterococcus faecalis(13 cases), Klebsiella pneumoniae(1 case) and Enterobacter gergeviae(1 case). 4) Enterococcus faecalis expressed not only nickel resistance but also the multi-drug resistance to several antibiotics ; chloramphenicol, kanamicin, streptomycin, lincomycin, clindamycin. However, all strain showed the sensitivity against the tetracycline. 5) DNA hybridization result suggest that there is no homology between the previousely known gene of nickel resistance in Klebsiella pneumoniae and chromosomal DNA of Enterococcus faecalis.