• The Journal of Korean Academy of Prosthodontics
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• v.48 no.4
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• pp.287-293
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• 2010

Purpose: This study evaluated the effect of polishing techniques on surface roughness of polymethyl methacrylate (PMMA), as well as the influence of light-cured surface glaze and subsequent brushing on surface roughness. Materials and methods: A total of 60 PMMA specimens ($10{\times}10{\times}5\;mm$) were made and then divided into 6 groups of 10 each according to the polymerization methods (under pressure or atmosphere) and the surface polishing methods (mechanical or chemical polishing) including 2 control groups. The mechanical polishing was performed with the carbide denture bur, rubber points and then pumice and lathe wheel. The chemical polishing was performed by applying a light-cured surface glaze ($Plaquit^{(R)}$; Dreve-Dentamid GmbH). Accura $2000^{(R)}$, a non-contact, non-destructive, optical 3-dimensional surface analysis system, was used to measure the surface roughness (Ra) and 3-dimensional images were acquired. The surface roughness was again measured after ultrasonic tooth brushing in order to evaluate the influence of brushing on the surface roughness. The statistical analysis was performed with Mann-Whitney test and t-test using a 95% level of confidence. Results: The chemically polished group showed a statistically lower mean surface roughness in comparison to the mechanically polished group (P = .0045) and the specimens polymerized under the atmospheric pressure presented a more significant difference (P = .0138). After brushing, all of the groups, except the mechanically polished group, presented rougher surfaces and showed no statistically significant differences between groups. Conclusion: Although the surface roughness increased after brushing, the chemical polishing technique presented an improved surface condition in comparison to the mechanical polishing technique.

• The korean journal of orthodontics
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• v.38 no.1
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• pp.52-59
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• 2008

Objective: This study analyzed the morphologic changes of the fourth cervical vertebra body to determine the skeletal age of orthodontic patients during growth. Methods: Eighty-one female patients aged from 11 to 14 who had cephalograms taken on the same day were examined. The subjects were divided into three groups depending on the depth of the concavity of the lower border of the fourth cervical vertebra (Group A: less than 1.05 mm, Group B: 1.05 - 2.07 mm, Group C: greater than 2.07 mm). Menarcheal timing, SMI stage, length, width and ratio of length and width of the fourth cervical vertebra body were analyzed and the following results were obtained. Results: The average SMI stage of group A, B and C were $5.67{\pm}2.57,\;8.73{\pm}2.41,\;and\;10.00{\pm}1.47$, respectively. Length, width, ratio of length and width, and SMI stage were greater in group B than group A and in group C than group B. Mean menarcheal timing was $11.64{\pm}0.92$ years. Concavity depth, length, width, ratio of length and width showed a significant positive correlation with SMI stage, especially with the concavity depth. Conclusion: The results of this study propose a simple method for determining the timing of orthopedic treatment by measuring the concavity depth of the fourth cervical vertebra on the cephalogram.

• Journal of Food Hygiene and Safety
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• v.35 no.3
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• pp.271-278
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• 2020

Enterotoxigenic Escherichia coli is one of the major causative infectious agents of diarrhea in newborn and post-weaning pigs and leads to a large economic loss worldwide. However, there is limited information on the distribution and characterization of virulence genes in E. coli isolated from diarrheic piglets, which also applies to the current status of pig farms in Korea. To investigate the prevalence and characterization of virulence genes in E. coli related to diarrhea in piglets, the rectal swab samples of diarrheic piglets (aged 2 d to 6 w) were collected from 163 farms between 2013 and 2016. Five to 10 individual swab samples from the same farm were pooled and cultured on MacConkey agar plates, and E. coli were identified using the API 32E system. Three sets of multiplex PCRs were used to detect 13 E. coli virulence genes. As a result, a total of 172 E. coli isolates encoding one or more of the virulence genes were identified. Among them, the prevalence of individual virulence gene was as follows, (1) fimbrial adhesins (43.0%): F4 (16.9%), F5 (4.1%), F6 (1.7%), F18 (21.5%), and F41 (3.5%); (2) toxins (90.1%): LT (19.2%), STa (20.9%), STb (25.6%), Stx2e (15.1%), EAST1 (48.3%); and (3) non-fimbrial adhesin (19.6%): EAE (14.0%), AIDA-1 (11.6%) and PAA (8.7%), respectively. Taken together, various pathotypes and virotypes of E. coli were identified in diarrheic piglets. These results suggest a broad array of virulence genes is associated with coliform diarrhea in piglets in Korea.

• The Korean Journal of Ecology
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• v.25 no.3 s.107
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• pp.189-195
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• 2002

In order to elucidate the budget and cycling of Nitrogen and Sulfur, essential elements and principal constituents of acid rain, their input through precipitation, and their output by streamflow were quantified in coniferous and deciduous forested watersheds, using combination of nutrient concentration and hydrological analysis, in Kwangnung Experimental Forest from July 1991 to December 1993. Amount of annual mean precipitation was $12,916\;ton{\cdot}ha^{-1}{\cdot}yr^{-1}$, annual mean runoff $5,094\;ton{\cdot}ha^{-1}{\cdot}yr^{-1}$(39%), $7,467\;ton{\cdot}ha^{-1}{\cdot}yr^{-1}$(59%) in coniferous and deciduous forest watersheds, respectively. Amounts of annual input of $N({NO_3}^-+{NH_4}^+)$ and ${SO_4}^{2-}$ through preciptation were 12.5, $81.72\;kg{\cdot}ha^{-1}{\cdot}yr^{-1}$, repectively. Annual output via runoff of $N({NO_3}^-+{NH_4}^+)$ and ${SO_4}^{2-}$ were 0.06, $39.23\;ton{\cdot}ha^{-1}{\cdot}yr^{-1}$ in the coniferous forest watershed ecosystem, and 0.15, $55.46\;ton{\cdot}ha^{-1}{\cdot}yr^{-1}$ in the deciduous one, respectively. On the basis of annual nutrient input and output, the annual budget of $N({NO_3}^-+{NH_4}^+)$ and ${SO_4}^{2-}$ were +12.46, $+42.49\;ton{\cdot}ha^{-1}{\cdot}yr^{-1}$ in the coniferous forest watershed, and +11.35, $+26.26\;ton{\cdot}ha^{-1}{\cdot}yr^{-1}$ in the deciduous one. Thus $N({NO_3}^-+{NH_4}^+)$ and ${SO_4}^{2-}$ were accumulated in both forested watershed ecosystems.

• The Korean Journal of Rehabilitation Nursing
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• v.3 no.1
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• pp.43-58
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• 2000

Pain management is a major issue in caring of cancer patients. Patients' concerns for reporting pain and taking analgesics are patient-related barriers to the management of cancer pain. Since such study has not been done at all in Korea, it is clearly needed to study on these problems. The purpose of this study is to attain basic data in order to improve cancer pain management in Korea. This is done by: 1) examining the extent of patients' concerns that might be barriers to the optimal pain management, and the extent of related factors (pain management hesitancy, adequacy of using analgesics, pain severity and pain interference); 2) identifying the relationship between patients' concerns and the related factors. The data has been collected from 180 cancer patients who were hospitalized in medical wards of one university hospital in Seoul, Korea during the period from November 1, 1997 to February 28, 1998. The data has been collected through interviews with (1) Barriers Questionnaire - Korean Version (BQ-K); (2) Hesitancy Experience Questionnaires (HQ); (3) Pain Management Index (PMI); (4) Brief Pain Inventory (BPI); and (5) Demographic Data. The data were analyzed by descriptive statistics and by t-test, One-way ANOVA, Pearson correlation using SPSSWIN program. The Results are as following: 1) The mean scores of Pain Management Concerns (PMC) by BQ-K were toward the moderate with a little high points(2.59). Most of the patients (99.4%) had some extent of concerns (over lout of maximum 5 points). Among the eight subscales of BQ-K, the Pain Management Concerns (PMC) about 'Fear of tolerance' was the highest (3.80) and 'Worry about side effects' was the least (1.40). 2) The extent of Pain Management Hesitancy (PMH) by HQ of wnom had pain on the day of the interview was a little higher than moderate score(5.53 out of maximum 10 points). 6.7% of the patients with experiencing pain used less adequate analgesics for the severity of pain than they were expected. 27.8% of them never used any analgesics at all. The mean score of pain severity by BPI was 16.59 (maximum: 40), and that of the interference with daily life by BPI was 32.03 (maximum: 70). 3) The patients who were older, less educated, and in low socio-economic status were likely to have more concerns. Pain Management Concerns (PMC) was positively correlated with Pain Management Hesitancy (PMH) (r=.75), pain severity (r=.44) and pain interference (r=.50). Those who were not using adequate analgesics had higher Pain Management Concerns (PMC) than did those who were using adequate analgesics (t=-5.42). The patients who had more Pain Management Concerns (PMC) tended to hesitate more to report pain and to use analgesics. They used more inadequate analgesics for the severity of pain and also had experienced more pain severity and interference with daily life. In conclusion, the patients' concerns for reporting pain and for using analgesics are major patient-related barriers to cancer pain management in Korea. The patients' concerns were correlated significantly with the level of the hesitancy experience, inadequate use of analgesics, the pain severity and the interference with daily life. Considering this, an educational program for cancer patients under the treatment with analgesics should be developed in order to solve these problems.

• Journal of Korean Public Health Nursing
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• v.1 no.1
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• pp.32-44
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• 1987

The purpose of this survey was to find out the knowledge and the disease management of the Tuberculosis patients by themselves among the first grade middle and high school students in Seoul city during the period of June 15-July 19, 1986. Questionaires were used to collect the data and were analysed from answers of 188 students at the 113 schools. The results were as follows: 1. The ages of the students were distributed as follows: in middle school, 13 years old was $70.0\%$. 14 years old, $20.0\%$, and 15 years old, $6.7\%$. In high school, 16 years old was $66.5\%$, 17 years old, $18.4\%$, and 15 years old, $10.1\%$. 2. In X-ray mass examination by school, the rate of execution was $50.4\%$ in middle school and $96.7\%$ in high school, and in X-ray mass examination by student, it was $50.1\%$ in middle school and $97.3\%$ in high school. 3. The prevalence of Tuberculosis among the middle school students was $00.3\%$and high school students, $0.15\%$. 4. Of the total, $77.1\%$ of the respondents did not realized Tuberculosis bdore X-ray mass examination 5. The perfect cure rate of the respondents was $52.7\%$. 6. General characteristics of the respondents: a. The educational background was varied as follows: of the total $47.9\%$ of the fathers had the level of high school education and $37.2\%$ of the mothers had the level of middle school education. The educational background of the parents had no statistical significant to the medical cure rate of Tuberculosis. (P>0.05). b. The average monthly income of the family was as follows : above five hundred thousand won was $21.8\%$, three or four hundred thousand won was $22.9\%$, and below two hundred thousand won was $10.6\%$. The most frequent family size was 5-6 persons. $(59.6)\%$. 7. The actual situation of Tuberculosis control and the variables related to the treatment: a. $69.1\%$ of the respondents wanted mental support from their surroundings. $48.7\%$ of the respondents answered that their parents or the other family helped treatment as mental supporter, b. As a medical service, $53.2\%$ of the respondents were treated at Health Center, $38.8\%$ were treated at a hospital. A medical service was statistically significant to the medical cure (P<0.01). c. Family members of $61.7\%$ of the respondents had checked chest X-ray. A X-ray examination of family was statistically significant to the medical cure (P<0.005). d. $73.9\%$ of the respondents had taken the Anti-Tuberculosis-drugs regularly. Regular taking of Anti-Tuberculosis drugs was statistically significant to the medical cure (P<0.005). e. $89.4\%$ of the respondents had received a regular examination during the treatment. A regular examination was statistically significant to the medical cure (P<0.05). f. The period of perfect cure was that $50.0\%$ of the respondents took from half a year to one year, $25.2\%$ took below half a year and $16.2\%$ took from one year to one year and a half. g. The rate of the respondents who abhored to let anyone know their disease was $93.1\%$. 8. Knowledge related with Tuberculosis: a .$63.3\%$ of the respondents answered that Tuberculosis is a communiable disease. b. $89.9\%$ of the respondents answered that there is a preventive method of Tuberculosis. Among them, $28.4\%$ answered that it is B.C.G. vacination. c. $96.8\%$ of the respondents belived they can be cured perfectly. d. $42.4\%$ of the perfect curer answered that they had have permanent immunity of Tuberculosis. According to the results of above study, it is desired to be practiced X-ray mass examination to the total middle school students. Nurse teachers and the responsible persons who participated to the helping of disease management to the Tuberculosis patients must make an offer knowledge of Tuberculosis to the Tuberculosis patients. And also, it will be very helpful to the cure of Tuberculosis patients if they do their best and to have a mental supporter.

• The Korean Journal of Petroleum Geology
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• v.2 no.2 s.3
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• pp.43-50
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• 1994

The geologic structure of Gongju Basin, which is a Cretaceous sedimentary basin located on the boundary of Gyeonggi Massif and Ogcheon Belt, is modeled by using gravity data and interpreted in relation with basin forming tectonism. The electrical survey with dipole-dipole array was also conducted to uncover the development of fractures in the two fault zones which form the boundaries of the basin. In the process of gravity data reduction, the terrain correction was performed by using the conic prism model, which showed better results specially for topography having a steep slope. The gravity model of the geologic structure of Gongju basin is obtained by forward modeling based on the surface geology and density inversion. It reveals that the width of the basin at its central part is about $4{\cal}km$ and about $2.5{\cal}km$ at the southern part. The depth of crystalline basement beneath sedimentary rocks of the basin is about $700{\~}400{\cal}m$ below the sea level and it is thinner in the center than in margin. The fault of the southeastern boundary appears more clearly than that of the northwestern boundary, and its fracture zone may extended to the depth of more than $1{\cal}km$. Therefore, it is thought that the tectonic movement along the fault in the southeastern boundary was much stronger. These results coincide with the appearance of broad low resistivity anomaly at the southeastern boundary of the basin in the resistivity section. The fracture zones having low density are also recognized inside the basin from the gravity model. The swelling feature of basement and the fractures in sedimentary rocks of the basin suggest that the compressional tectonic stress had also involved after the deposition of the Cretaceous sediments.

• Journal of Biomedical Engineering Research
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• v.37 no.1
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• pp.7-14
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• 2016

Radiopharmaceutical agents for positron emission tomography (PET), such as $^{18}F$-FDG and $^{68}Ga$, have been used not only for whole-body PET imaging but also for intraoperative radionuclide-guided surgery due to their quantitative and sensitive imaging characteristics. Current intraoperative probes detect gamma or beta particles, but not both of them. Gamma probes have low sensitivities since a collimator has to be used to reduce backgrounds. Positron probes have a high tumor-to-background ratio, but they have a 1-2 mm depth limitation from the body surface. Most of current intraoperative probes produce only audible sounds proportional to count rates without providing tumor images. This research aims to detect both positrons and annihilation photons from $^{18}F$ using plastic scintillators and a GAGG scintillation crystal attached to silicon photomultiplier (SiPM). The depth-of-interaction (DOI) along the plastic scintillator can be used to obtain the 2-D images of tumors near the body surface. The front and rear part of the intraoperative probe consists of $4{\times}1$ plastic scintillators ($2.9{\times}2.0{\times}12.0mm^3$) for positron detection and a Ce:GAGG scintillation crystal ($12.0{\times}12.0{\times}9.0mm^3$) for annihilation photon detection, respectively. The DOI resolution of $4.4{\pm}1.6mm$ along the plastic scintillator was obtained by using the 3M enhanced specular reflector (ESR) with rectangular holes between the plastic scintillators, which showed the feasibility of a 2-D image pixel size of $2.9{\times}4.4mm^2$ (X-direction ${\times}$ Y-direction).

• Journal of the Korean Geographical Society
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• v.47 no.5
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• pp.755-774
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• 2012

The main objective of the study is to propose GIS-based methods to assess the population distribution criteria for undesirable facilities such as nuclear power plants. First of all, a review of the relevant criteria was conducted for the official documents compiled by such institutions as IAEA (International Atomic Energy Agency), U.S. NRC (Nuclear Regulatory Commission), and some national institutes including the Korea Institute of Nuclear Safety. It is informed from the review that the fundamental principle underlying the various criteria is to maximize the distance between a plant and the nearest population center. It is realized that two interrelated GIS-based techniques need to be devised to put the principle into practice; sophisticated ways of representing population distribution and identifying population centers. A dasymetric areal interpolation is proposed for the former and cell-based and area-based critical density methods are introduced. Grid-based population distributions at various spatial resolutions are created by means of the dasymetric areal interpolation. By applying the critical density methods to the gridded population distribution, some population centers satisfying the population size and density criteria can be identified. These methods were applied to the case of the Gori-1 nuclear power plant and their strengths and limitations were discussed. It was revealed that the assessment results could vary depending upon which method was employed and what values were chosen for various parameters. This study is expected to contribute to foster the applications of methods and techniques developed in geospatial analysis and modeling to the site selection and evaluation.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.11 no.2
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• pp.240-251
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• 2000

This study was a preliminary study on the adolescent psychiatric patients that show the characteristics of peer group neglect or rejection. We divided the adolescent psychiatric patients(n=25) into neglect-reject group(n=15) and non-neglect group(n=10). Each patient answered 8 scales and several questions about general relationships with friends. And, both the score of each 8 scales and answer about qusetions were examined. Lastly, records of 5 cases from neglect-reject group were analyzed. The depression dimension score of SCL-90-R, anxiety dimension score of SCL-9O-R, paranoid dimension score of SCL-90-R, interaction anxiousness scale(IAS) score were significantly different between 2 groups. On the result of case analysis about 5 patients of neglect-reject group, the adolescent psychiatric patients had a tendency to be rejected or neglected in case of having developmental problems(for example, language development or cognitive impairment).