• Journal of Periodontal and Implant Science
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• v.33 no.3
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• pp.457-474
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• 2003

The ultimate objective of periodontal treatment is to get rid of an on-going periodontal disease and further regenerate the supporting tissue, which is already destroyed, functionally. Currently, the bone grafting operation using various kinds of bone grafting materials and the operation for induced regeneration of periodontal tissue using the blocking membrane are performed for regeneration of the destroyed periodontal tissue. However, there are respective limitations Galenical preparations, which are used for regeneration of periodontal of tissue, has less risk of rejective reaction or toxicity that may be incidental to degradation and their effect is sustainable. Thus, in case they are applicable to a clinic, they can he used economically. Chitosan has such compatibility, biological actions including antibacterial activity, acceleration of wound treatment, etc., and excellent mechanical characteristics, which has recently aroused more interest in it. Also, it has been reported that it promotes osteogenesis directly or indirectly by functioning as a matrix to promote migration and differentiation of a specific precussor cell (for example, osteoblast) and further inhibiting the function of such a cell as fibroblast to prevent osteogenesis. In this study, the pure chitosan solution, which was obtained by purifying chitosan, was used. However, since this chitosan is of a liquiform, it is difficult to sustain it in a defective region. It is, therefore, essential to use a carrier for delivering chitosan to, and sustaining it gradually in the defective region. In the calvarial defect model of the Sprague-Dawley rat, it is relatively easy to maintain a space. Therefore, in this study, the chitosan solution with which ACS was wetted was grafted onto the defective region, For an experimental model, a calvarial defect of rat m s selected, and a critical size of the defective region was a circular defect with a diameter of 8 mm. A group in which no treatment was conducted for the calvarial defect was set as a negative control group. Another group in which treatment was conducted with ACS only was set as a positive control group (ACS group). And another group in which treatment was conducted was conducted with by grafting the pure chitosan solution onto the defective region through ACS which was wetted with the chitosan solution was set an experimental group (Chitosan/ACS group). Chitosan was applied to the Sprague-Dawley rat's calvarial bone by applying ACS which was wetted with the chitosan solution, and each Sprague-Dawley rat was sacrificed respectively 2 weeks and 8 weeks after the operation for such application. Then, the treatment results were compared and observed histologically and his tometrically. Thereby, the following conclusions were obtained. 1. In the experimental group, a pattern was shown that from 2 weeks after the operation, vascular proliferation proceeded and osteogenesis proceeded through osteoblast infiltration, and at 8 week after the operation, ACS was almost absorbed, the amount of osteogensis was increased and many osteoid tissue layers were observed. 2. At 2 weeks after the operation, each amount of osteogenesis appeared to be 8.70.8 %, 13.62.3 % and 4.80.7 % respectively in the experimental group, the positive control group and the negative control group. Accordingly, it appeared to be higher in the Experimental group and the positive control group than in the negative control group, but there was no significant difference statistically (p<0.01). 3. At 8 weeks after the operation, each amount of osteogenesis appeared to be 62.26.1%, 17.42.5 % and 8.21.4 % respectively in the experimental group, the positive control group and the negative control group. Accordingly, it appeared to be substantially higher in the experimental group than in the positive control group and the negative control group, and there was a significant difference statistically (p<0.01). As a result of conducting the experiment, when ACS was used as a carrier for chitosan, chitosan showed effective osteogenesis in the perforated defective region of the Sprague-Dawley rat's calvarial bone.

• Journal of radiological science and technology
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• v.38 no.2
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• pp.163-170
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• 2015

The interest of the people in the radioactive contamination of the water has increased significantly and the study about analysis and management of radioactive materials are being actively conducted. And monitoring spots have been expanded to the range of public water as well as drinking water by publishing the rule of drinking water quality standards and examination in the Environmental Enforcement Ordinance No. 553 of Korea. In this study, US EPA was investigated as the foreign advanced cases and the way that is appropriate for the Korea was sought by analyzing investigate radionuclide, interval and management. As a result, in the selection part of investigate radionuclide, geological survey, status of nuclear power plants and the presence of the use of artificial radionuclides of the Korea should be investigated and additionally after the selection of a few radionuclides, the systems should be extended to cover all possible radionuclides by considering radioactive pollution levels in humans may be exposed due to the annual drinking water. In the part of the investigate interval, the concept(MCL, DL) should be set up for preventing concentration detection of above MCL and it needs to the maintenance and management. For example, when the concentration is more than MCL, it should be investigated on a quarterly and when the concentration is lower than MCL, it should be investigated to each different interval and management. And the US EPA divided the management area and make the roadmap for managing drinking water. The each classified area has been organized to match the state budget and labor force and the individual data have been managed effectively by HPGe, the NaI, TLD and so on.

• Tuberculosis and Respiratory Diseases
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• v.41 no.5
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• pp.537-545
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• 1994

Background: In 1987, the British Thoracic Society (BTS) subjected an extensive list of patient variables to statistical analysis in a prospective study of prognosis in 453 adults with community-acquired pneumonia and, subsequently published guidelines for management of severe community acquired pneumonia. It was hoped that those at risk of dying from community acquired pneumonia could be easily identified and treated appropriately, thereby reducing mortality. To date, severe community acquired pneumonia has not been well studied in Korea. Therefore, we studied retrospectively 10 patients dying of severe community acquired pneumonia in Dongsan Hospital to see clinical manifestations of dying of severe community-acquired pneumonia. Methods: Between July 1987 and july 1993, 498 patients were admitted to Keimyung University Dongsan Hospital with community acquired pneumonia, and 77 of them received intensive care. Of the 77 patients, 10 patients died. We reviewed medical records of these patients. Results: 1) The mean age of the patients was 56.2 years(range, 25 to 75 years). There were 7 men and 3 women. Seven patients(70%) were older than 60years of age. 2) The clinical features on admission were as follows: tachypnca, hypoxemia, mental change, cyanosis, leukopenia, leukocytosis, azotemia, hypotension, hypoalbuminemia in order of frequency. Three patients had one abnormal physical finding, 3 patients had 2, 2 patients had 3, and 2 patients had none of these abnormal physical findings. All patients had at least one of the abnormal laboratory findings. 3) A potential bacterial pathogen was isolated in sputum culture from 2 patients. One was E.coli, the other Enterobacter species. Sputum stain were positive in eight cases (G(+)cocci in six, G(+) cocci and G(-)bacilli in two). 4) Features of respiratory failure were the main reasons for ICU transfer, but two patients were transferred only following a cardiac or respiratory arrest in the general ward. 5) The mean of 2.7 different antibiotics were given to the patients. The aminoglycoside and first generation cephalosporin were the most frequently prescribed antibiotics, followed by the third generation cephalosporin and vancomycin. The most frequently prescribed antibiotics combination was a 1st generation cephalosporin plus an aminoglycoside. 6) Seven patients death(70%) occured after admission within the first five days, and a mean duration of hospitaliztion was 11.2 days. Conclusion: As the results show most death occured within the first five days after admission and aged patients; consequently, an aggressive intensive treatment should be provided early to the patients with severe community acquired pneumonia, and we should pay more attention to the aged patients.

• Korean Journal of Biological Psychiatry
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• v.22 no.4
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• pp.187-194
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• 2015

Objectives To examine direct causes of attempted suicides, methods adopted to commit suicide, and psychiatric diagnoses among suicide attempters in South Korea. Methods A total of 1359 suicide attempters who had visited emergency department of 17 medical centers due to suicide attempt from May 2013 to Nov 2013 were interviewed using semi-structured questionnaires. Results Psychiatric symptoms were the most common cause of suicide attempts (62.2%), followed by interpersonal relationships (24.4%). Women attempted suicide more often for interpersonal reasons, whereas men were more likely to do so for financial and job-related reasons. Half of participants (55.8%) attempted suicide by drug intoxication, which was more prevalent among females and those who had previous history of psychiatric disease or previous suicide attempt. Men were more likely to use more lethal methods such as pesticide poisoning and gas inhalation than women. Pesticide poisoning was also prevalent among the elderly group and the rural population. Near ninety-five percent (94.5%) of participants received a psychiatric diagnosis : the most frequent diagnosis was depressive disorder. Conclusions This is the first nationwide study of cases of attempted suicide. When stratified by age groups, gender, urbanicity, living alone or not, presence of physical illness, previous psychiatric history, and previous suicide attempt, there were significant differences with respect to causes, methods of attempted suicides and psychiatric diagnoses of suicide attempters.

• Restorative Dentistry and Endodontics
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• v.30 no.5
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• pp.423-430
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• 2005

Ameloblasts are responsible for the formation and maintenance of enamel which is an epithelially derived protective covering for teeth. Ameloblast differentiation is controlled by sequential epithelial-mesenchymal interactions. However, little is known about the differentiation and maturation mechanisms. OD314 was firstly identified from odontoblasts by subtraction between odontoblast/pulp cells and osteoblast/dental papilla cells, even though OD314 protein was also expressed in ameloblast during tooth formation. In this study, to better understand the biological function of OD314 during amelogenesis, we examined expression of the OD314 mRNA and protein in various stages of ameloblast differentiation using in-situ hybridization and immunohistochemistry. The results were as follows : 1. The ameloblast showed 4 main morphological and functional stages referred to as the presecretory, secretory, smooth-ended, and ruffle-ended. 2. OD314 mRNA was expressed in secretory ameloblast and increased according to the maturation of the cells. 3. OD314 protein was not expressed in presecretory ameloblast but expressed in secretory ameloblast and maturative ameloblast. OD314 protein was distributed in entire cytoplasm of secretory ameloblast. However, OD314 was localized at the proxiamal and distal portion of the cytoplasm of smooth-ended and ruffle-ended ameloblast. These results suggest that OD314 may play important roles in the ameloblast differentiation and maturation.

• Food Science and Preservation
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• v.16 no.6
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• pp.908-914
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• 2009

A central composite design was used to optimize extraction of propolis materials using ethanol. The independent variables in extraction experiments were ethanol concentration (50, 60, 70, 80, 90%, v/v) and extraction time (1, 2, 3, 4, and 5 h). Higher ethanol concentration and shorter extraction time increased total polyphenol content, but total polyphenol concentration began to decrease when ethanol concentration was higher than 80% (v/v). Ethanol concentration was more important than extraction time in optimization of total polyphenol content in propolis extracts. Electron-donating ability increased with ethanol concentration and shorter extraction time, with ethanol concentration being of greater significance. Antioxidant ability in extracts was optimal at an ethanol concentration of 65 - 75% and with an extraction time of 2.2 - 3.6 h. Nitrite-scavenging ability was increased with use of higher ethanol concentration and shorter extraction time. Total flavonoid content was maximized with an ethanol concentration of 68 - 82% and an extraction time of 2.4 - 3.7 h. Total flavonoid content was affected by both ethanol concentration and extraction time. By superimposition of contour plots, an ethanol concentration of 72 - 82% and an extraction time of 2.2 - 3.3 h were optimal for preparation of propolis extracts.

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.315-322
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• 2007

This study was carried out to investigate the functional activities of microorganisms isolated from kochujang, such as fibrinolytic, immunostimulating, and cytotoxical activities, and to apply these microorganisms to kochujang products. Ninety-one microbial strains with proteolytic activity were selected from 294 strains isolated from traditional and commercial kochujang. Three strains (TPP 0014, TPP 6013, and TPP 6015) with high fibrinolytic activity were tested for their immunostimulating and cytotoxical activities. For the assessment of macrophage activation, cytokines such as tumor necrosis factor, $interleukin-1{\alpha}$ and nitrogen oxide were measured with the murine macrophage cell line RAW 264.7. In addition, the cytotoxical activities of the three strains were examined by MTT assay on the colon cancer cell line SNU-C4 and normal cell line CHO-K1. Using an API identifying kit, two of the microbial strains (TPP 0014 and TPP 6015) were identified as Bacillus stearothermophilus and the other strain (TPP 6013) was identified as B. amyloliquefacience.

• Journal of the Microelectronics and Packaging Society
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• v.14 no.3
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• pp.1-6
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• 2007

In this study, the pentacene thin films were prepared by the soluble process, and characterized fur the application of the organic thin film transistor(OTFT) device. To dissolve the pentacene material, two kinds of solvents such as toluene and chloroform were used, and the effects of these solvents on the properties of pentacene thin films coated on ITO/Glass substrate were investigated. Pentacene thin films were prepared by using spin-coating methode and characterized the surface morphology, crystalline and electrical properties. From the AFM measurement, the surface morphology of the pentacene film dissolved with chloroform was improved compared with the one dissolved with toluene solvent. XRD measurement showed that all prepared pentacene film samples were amorphous crystal phases without crystallization of the films. The electrical properties of the pentacene film dissolved with chloroform showed better results than the ones using toluene solvent by hall measurement system. The carrier concentration and the mobility values of pentacene films using chloroform solvent were found to be $-3.225{\times}10^{14}\;cm^{-3}$ and $3.5{\times}10^{-1}\;cm^2{\cdot}V^{-1}{\cdot}S^[-1}$, respectively. The resistivity was about $2.5{\times}10^2\;{\Omega}{\cdot}cm$.

• Food Science and Preservation
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• v.13 no.6
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• pp.740-748
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• 2006

The Chunma (Gastrodia elata Blume) requires a simple pre-treatment, due to inconvenience or preservation, toxicities, and pungencies in intact state. Various drying conditions were examined to establish the physicochemical properties of Chunma by the response surface methodology (RSM). Weter activity and total phenolic acid contents of Chunma dried extracts were optimal at $79.56^{\circ}C$ and $79.64^{\circ}C$ for 7.17 hr and 8.74 hr, respectively, for their characteristics. Electron-donating ability and nitrite-scavenging activity were optimal at 79.79 and $7.99^{\circ}C$ for 8.57 and 8.07 hr. We generated a regression equation for each variable and then superimposed the optimal condition in acquiring values for each frying process factor, physicochemical properties, resulting in that the optimal drying condition was at $75{\sim}80^{\circ}C$ for $8{\sim}9 hr$.

• Journal of Hydrogen and New Energy
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• v.23 no.4
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• pp.364-372
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• 2012

Transient mixing states of two different fuel oils, dimethylformamide (DMF) oil and JetA1 oil, were investigated by using a color image processing and a neural network. A tank ($D{\times}H$, $310{\times}370mm$) was filled with JetA1 oil. The DMF oil was filled at a top tank, and was mixed with the JetA1 oil in the tank mixing tank via a sudden opening which was performed by nitrogen gas with 1.9 bar. An impeller was rotated with 700 rpm for mixing enhancements of the two fuel oils. To visualize the mixing state of the DMF oil with the JetA1 oil, the DMF oil was coated with Rhodamine B whose color was red. A LCD monitor was used for uniform illumination. The color changes of the DMF oil were captured by a camcoder and the images were transferred to a host computer for quantifying the information of color changes. The color images of two mixed oils were captured with the camcoder. The R, G, B color information of the captured images was used to quantify the concentration of the DMF oil. To quantify the concentration of the DMF oil in the JetA1 oil, a calibration of color-to-concentration was carried out before the main experiment was done. Transient mixing states of DMF oil with the JetA1 oil since after the sudden infiltration were quantified and characterized with the constructed visualization technique.