• The korean journal of orthodontics
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• v.25 no.1 s.48
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• pp.55-72
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• 1995

The purpose of this study is to evaluate the effects of mechanical and thermal fatigue on the shear bond strength(SBS) in orthodontic brackets bonded to human premolars with chemically cured adhesive(Mono-$Lok^2$, Rocky Mountain Orthodontics). Two types of metal brackets (Ormesh, Microloc) and three types of ceramic brackets (Fascination, Starfire, Transcend 2000) were used in this study. The $10^6$ loadcycles of $|7.4{\times}10{^2}sin2{\pi}ft|g{\cdot}cm$ and the 1,000 thermocycles of 15 second dwell time each in $5^{\circ}C\;and\;55^{\circ}C$ baths were acturated as mechanical and thermal fatigue stress, and SBS were measured after each fatigue test. The fracture sites were examined by stereoscope and scanning electron microscope. The results obtained were summarized as follows, 1. In static shear bond test, Fascination brackets showed the maximum SBS($20.78\pm3.45$ MPa) and Microloc brackets showed the minimum SBS($14.88\pm3.10$ MPa). Fascination and Starfire brackets showed significantly greater SBS than Microloc brackets(P<0.05). 2. In mechanical fatigue test, Fascination brackets showed the maximum SBS ($20.19\pm3.45$ MPa) and Starfire brackets showed the minimum SBS($9.10\pm8.33$ MPa). The SBS or Transcend 2000 brackets(P<0.01) and Starfire brackets(P<0.05) significantly decreased after $10^6$ loadcycles. 3. In thermocycling test, Ormesh brackets showed the maximum SBS ($19.36\pm2.76$ MPa) and Starfire brackets showed the minimum SBS($11.94\pm6.86$ MPa). The SBS of Transcend 2000(P<0.01), Microloc and Starfire brackets(P<0.05) significantly decreased after $10^3$ thermocycles. 4. Failure sites of thermocycling groups were similar to those of static groups but after mechanical fatigue test, Ormesh and Transcend 2000 brackets failed at the bracket/resin interface and Microloc brackets failed within adhesive. Facination brackets failed at the enamel/resin interface irrespective of experimental condition.

• The korean journal of orthodontics
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• v.38 no.3
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• pp.214-222
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• 2008

Objective: The aim of this study was to investigate the experimental brush wear pattern of a light cured surface sealant, Biscover (Bisco, Schaumburg, IL), and to evaluate its cariostatic effect. Methods: Caries-free human premolars were used for the Biscover coating group (n = 90) and the control group (n = 10). The Biscover coating group was randomly assigned to nine subgroups of 10 each and the control group was assigned to two subgroups of 5 each according to the number of brushing strokes. An experimental 3-body wear test was conducted under different strokes of wear test. Tooth-brushing was accomplished with movement of each brush head set at a frequency of 100 rpm under a force of 1.5N, Surface roughness was tested before, and after Biscover coating, and after brushing. Then, each of the 10 teeth of both groups were placed in artificial caries inducing solution for 7 days. All tooth surfaces were assessed using scanning electron microscopy. Results: Biscover coated surfaces showed a smoother texture than enamel surfaces. The roughness was increased after experimental brushing and after 10,800 brushing strokes, the whole layer of Biscover wore out. However, teeth in the Biscover coating group had a cariostatic effect in cariogenic conditions. Conclusions: We suggest that white lesions in orthodontic patients can be suppressed by topical applications of Biscover.

• Tuberculosis and Respiratory Diseases
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• v.64 no.2
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• pp.102-108
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• 2008

Background: Recently, multidrug-resistant (MDR) A. baumannii has been implicated for a significant proportion of nosocominal pneumonia in many intensive care units (ICUs), and its acquisition may increase mortality and the length of stay in the ICU. Aerosolized colistin has been successfully used in patients with cystic fibrosis, but there is a lack of data regarding the use of aerosolized colistin in patients with nosocomial pneumonia. Methods: We conducted the present study to assess the effectiveness of aerosolized colistin for the treatment of MDR A. baumannii nosocomial pneumonia. We retrospectively reviewed the medical records of 10 patients who had been hospitalized in the medical ICU and had received aerosolized colistin as a therapy for MDR A. baumannii pneumonia. Results: The mean duration of aerosolized colistin therapy was $12.7{\pm}2.4$ days. Nine (90%) of 10 patients showed a favorable response to the therapy. Follow-up cultures were available for all patients, and the responsible pathogen was completely eradicated. One patient suffered from bronchospasm, which resolved after treatment with nebulized salbutamol. Conclusion: Our results corroborate previous reports that aerosolized colistin may be an effective and safe choice for the treatment of nosocomial pneumonia caused by MDR A. baumannii. Larger prospective controlled clinical studies are warranted to validate further the effectiveness and safety of aerosolized colistin therapy.

• Progress in Medical Physics
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• v.20 no.4
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• pp.317-323
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• 2009

The standard dosimetry systems based on an absorbed dose to water recommend to use a planeparallel chamber for the calibration of such a low-megavoltage electron beam as a nominal energy of 6 MeV. For this energy ranges of an electron beam a cylindrical chamber should not be used for the routinely regular beam calibration, but the feasibility of the temporary use of a cylindrical chamber was studied to give temporary solutions for special situations users meet. The PTW30013 chambers and the electron beam quality of $R_{50}=2.25\;g/cm^2$ were selected for this study. 10 PTW30013 chambers, a cylindrical type of chamber, were calibrated in KFDA, the secondary standards dosimetry laboratories, and given the absorbed dose-to-water calibration factors, respectively. A "temporary" $k_{Q,Q_0}$ for each chamber were calculated using the absorbed dose determined by a cross-calibrated planeparallel chamber, with the result of an average 0.9352 for 10 chambers. This value for PTW30013 chamber was used to determine an absorbed dose to water at the reference depth. The absorbed doses determined by PTW30013 chambers were in an agreement within 2% with that by ROOS chamber. In a certain situation where a cylindrical chamber be used instead of a planeparellel chamber, the value of 0.9352 might be useful to determine an absorbed dose to water in the same beam quality of electron beam as this study.

• Journal of Environmental Impact Assessment
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• v.26 no.5
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• pp.365-375
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• 2017

This study investigated in the vascular plants of special protection zones (the native land of Iris koreana in Gaeamsa Temple and Soeppulbawi Rock) of Byeonsanbando National Park and identified the whole flora. The numbers of vascular plants were summarized as 255 taxa including 71 families, 166 genera, 222 species, 2 subspecies, 27 varieties and 4 forms. Woody plants were identified as 114 taxa (44.7%) and herbaceous plants as 141 taxa (55.3%). A total of 178 taxa were identified in the area of Gaeamsa Temple, and 184 taxa were found in the Soeppulbawi Rock. As a legal protected species, the endangered wild plant II grade Iris koreana designated by the Ministry of Environment was confirmed. A total of 6 taxa of rare plants were identified, each of which was divided into 1 taxa of critically endangered (CR; Iris koreana), 1 taxa of vulnerable (VU; Ilex cornuta), and 4 taxa of least concern (LC; Asarum maculatum, Viola albida, Chionanthus retusa and Tricyrtis macropoda). The Korean endemic plants were 11 taxa (Populus tomentiglandulosa, Lonicera subsessilis, Carex okamotoi, etc.). In the specific plants by floristic region were 38 taxa, a degree I were 23 taxa (Euscaphis japonica, Hedera rhombea, Lophatherum gracile, etc.), 7 taxa of a degree II (Viola violacea, Ainsliaea apiculata, Cephalanthera falcata, etc.), 6 taxa of a degree III (Ilex cornuta, Callicarpa mollis, Mitchella undulata, etc.), 1 taxa of a degree IV (Carex remotiuscula), 1 taxa of a degree V (Iris koreana). The Iris koreana special protection area that is more natural and healthier than any other areas in Byeonsanbando National Park. Therefore, it should be possible to continue its role as a special protection area through regular monitoring in the future.

• The Korean Journal of Food And Nutrition
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• v.30 no.2
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• pp.236-242
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• 2017

Chia (Salvia hispanica L.) seed, originated from Central America, is a nutritious food especially rich in dietary fiber and protein. In this study, we investigated the quality and sensory characteristics of Yanggang with chia seed powder (CSP). Red bean paste was replaced with CSP at 0% (Control), 1% (CSP1), 2% (CSP2), 3% (CSP3) and 4% (CSP4). The pH values of chia seed Yanggang tended to decrease from Control (6.84) to CSP4 (6.67); whereas, the moisture contents of Yanggang samples tended to increase. The soluble solid contents of CSP4 were the highest ($3.33^{\circ}Bx$), as compared to the Control which showed the lowest values ($2.77^{\circ}Bx$). In the CSP-added groups, the L-value (lightness), a-value (redness) and b-value (yellowness) were increased, while the ${\Delta}E$ (total color difference) was decreased, as compared to the control group. Hardness and springiness were both increased from control ($49.77g/cm^2$ and 464.80%, respectively) to CSP4 ($72.21g/cm^2$ and 532.43%, respectively). However, cohesiveness decreased from control (47.41%) to CSP4 (37.34%). Chewiness and adhesiveness showed no significant group-wise difference (p<0.05). Total polyphenol content ranged from 7.23 to 10.73 mg GAE/100 g, with a lower ABTS $IC_{50}$ of the CSP-added groups than that of the control group. Samples from the CSP-added as well as Control groups showed no significant differences among all items on the sensory evaluation test, except flavor. The results indicated that CSP had significant effects on the soluble solid contents and texture of Yanggang. Thus, the addition of 2% of CSP is desirable for making Yanggang.

• Childhood Kidney Diseases
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• v.8 no.2
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• pp.195-204
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• 2004

Purpose: Hypophosphatemic rickets is a hereditary disease, characterized by hypophosphatemia due to renal phosphate wasting, impaired renal production of 1,25-dihydroxyvitamin $D_3$, rachitic bone deformities and impaired growth. The purpose of this study is to provide clinical profiles of patients with hypophosphatemic rickets in our hospital. Methods: Between July 1983 and February 2004, 56 patients were diagnosed as having hypophosphatemic rickets. The medical records of these patients were reviewed retrospectively. Clinical manifestations, family histories, laboratory data, treatment outcomes were described. Results: Fifty six patients were enrolled in this study. The average age at symptom onset and diagnosis were 20 months and 5 years respectively. Fourteen patients had family histories. The main clinical manifestations were bow legs and short stature. There was a significant negative correlation between the ages and the height z-scores at the time of diagnosis(r=-0.47, P=0.005). Initial laboratory data showed normocalcemia, hypophosphatemia, elevated serum alkaline phosphatase, decreased tubular reabsorption of phosphate and a normal range of 1,25-dihydroxyvitamin $D_3$ Radiographic examinations of bone revealed fraying, widening and cupping of the metaphyseal ends. Treatment consisted of Joulie solution and vitamin D metabolites, and resulted in improved biochemical and radiographic findings. However, height z-scores remained essentially unchanged(P=0.224). Complications of treatment were frequently observed, including hyperparathyroidism, nephrocalcinosis, and hypercalciuria. Sixteen patients had corrective osteotomy and 4 of them underwent leg lengthening together. Conclusion: There was a gap of several years between the onset of symptoms and the diagnosis. Early treatment seems to be essential to growth. For the earlier treatment, the offsprings of affected parents should be followed up closely.

• Korean Journal of Poultry Science
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• v.36 no.4
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• pp.351-356
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• 2009

This work was carried out to investigate the effects of CDDGS (corn distillers dried grains with solubles) colors and phytase levels on the amino acid digestibility of broilers for 7 days. One hundred eight Ross broilers were used in 9 treatment groups with a $3\;{\times}\;3$ factorial design as three colors of DDGSs (DDGS1, DDGS2, and DDGS3) in combination with phytase (0, 500, and 1,000 FTU/kg). The $L^*$ values of DDGS1, DDGS2, and DDGS3 were 55.2, 39.8, and 28.3; the $a^*$ values, 8.8, 7.5, and 6.1; and the $b^*$ values, 41.3, 27.1, and 15.4, respectively. The ileal digestibility of amino acids was decreased as DDGS color was dark, and increased as additive phytase level was increased in the diet. Average digestibilities of essential amino acids were 67.6~80.0%, and those of nonessential amino acids 67.4~77.3. Amino acid digestibility was low in the dark DDGS with no phytase in the diet.

• Pediatric Infection and Vaccine
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• v.8 no.2
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• pp.135-149
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• 2001

Purpose : To describe the characteristics of the claims for compensation and the methodology of investigations concerning adverse events following immunization(AEFI) and epidemiologic characteristics of the AEFI. From these results, to give a suggestion for improving AEFI surveillance system, consequently to stabilize National Immunization Program. Methods : Totally 61 cases were reported to the National Compensation Program and surveillance system of AEFI from 1995 to 2000. Documents from National Compensation Program, medical records and epidemiologic investigation reports of the cases were collected and analyzed. Results : The number of reported cases was 12 in 1995, 3 in 1996, 12 in 1998, 5 in 1999, and 29 in 2000, respectively. That of deaths was 24(39.3%) and 16 cases among them were autopsied(66.7%). That of claims for compensation was 36 and 17 cases among them were compensated(47.2%). The proportion of claim was lower in 1999~2000 than in 1995~1998, but proportion of compensation increased. Although proportion of investigation was lower in 1999~2000 than in 1995~1998, cases which were not epidemiologically investigated, decreased. The epidemiologic investigation launched within 24 hours after report increased from 25% in 1995~1998 to 48.3% in 1999~2000. Among reported cases, the number of boys was 31(50.8%), and 75.4% of subjects were from 2 months to 24 months old. 78.4% of adverse events occurred within one week after immunization. Conclusion : We can find that surveillance system of AEFI and quality of epidemiologic investigation has been somewhat improved. But, it seems that severe cases were more frequently reported than moderate or mild cases, and reporting rate was lower than that of other developed countries. We could not identify the detailed epidemiologic characteristics of AEFI due to these limitation of data. To achieve the stabilization of National Immunization Program, reporting rate and the quality of investigation should be improved.

• Korean Security Journal
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• no.24
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• pp.147-170
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• 2010

This study is to present a improvement directions for the protection of industrial key technology. For the purpose of the study, the survey was carried out on the administrative security activity of 68 enterprises including Large companies, small-midium companies and public corporations. survey result on the 10 items of security policy, 10 items of personal management and 7 items of the assets management are as follows; First, stable foundation for the efficient implement of security policy is needed. Carrying a security policy into practice and continuous upgrade should be fulfilled with drawing-up of the policy. Also for the vitalization of security activity, arrangement of security organization and security manager are needed with mutual assistance in the company. Periodic security inspection should be practiced for the improvement of security level and security understanding. Second, the increase of investment for security job is needed for security invigoration. Securing cooperation channel with professional security facility such as National Intelligence Service, Korea internet & security agency, Information security consulting company, security research institute is needed, also security outsourcing could be considered as the method of above investment. Especially small-midium company is very vulnerable compared with Large company and public corporation in security management, so increase of government's budget for security support system is necessary. Third, human resource management is important, because the main cause of leak of confidential information is person. Regular education rate for new employee and staff members is relatively high, but the vitalization of security oath for staff members and the third party who access to key technology is necessary. Also access right to key information should be changed whenever access right changes. Reinforcement of management of resigned person such as security oath, the elimination of access right to key information and the deletion of account. is needed. Forth, the control and management of important asset including patent and design should be tightened. Classification of importance of asset and periodic inspection are necessary with the effects evaluation of leak of asset.