• Journal of Periodontal and Implant Science
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• 제42권3호
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• pp.88-94
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• 2012

Purpose: The use of appropriate instruments to clean surfaces with minimal change, is critical for the successful maintenance of a dental implant. However, there is no consensus about the type and methodology for such instruments. The aim of this study was to characterize changes in the roughness of titanium surfaces treated by various scaling instruments. Methods: Thirty-seven identical disks (5 mm in diameter) were investigated in this study. The specimens were divided into eight groups according to the types of instrumentation and the angle of application. Ultrasonic scaling systems were applied on a titanium disk to simulate standard clinical conditions. The equipment included a piezoelectric ultrasonic scaler with a newly developed metallic tip (NS group), a piezoelectric ultrasonic scaler with a conventional tip (CS group), a piezoelectric root planer ultrasonic scaler with a conventional tip (PR group), and a plastic hand curette (PH group). In addition, the sites treated using piezoelectric ultrasonic scaler systems were divided two sub-groups: 15 and 45 degrees. The treated titanium surfaces were observed by scanning electron microscopy (SEM), and the average surface roughness (Ra) and mean roughness profile depth (Rz) were measured with a profilometer. Results: SEM no significant changes in the titanium surfaces in the NS group, regardless of the angle of application. The PH group also showed no marked changes to the titanium surface, although some smoothening was observed. All CS and PR sites lost their original texture and showed irregular surfaces in SEM analysis. The profilometer analysis demonstrated that the roughness values (Ra and Rz) of the titanium surfaces increased in all, except the PH and NS groups, which showed roughness decreases relative to the untreated control group. The Ra value differed significantly between the NS and PR groups (P<0.05). Conclusions: The results of this study indicated that changes in or damage to titanium surfaces might be more affected by the hardness of the scaler tip than by the application method. Within the limitations of this study, the newly developed metallic scaler tip might be especially suitable for peri-implant surface decontamination, due to its limited effects on the titanium surface.

• Asian-Australasian Journal of Animal Sciences
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• 제26권2호
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• pp.202-210
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• 2013

This study elucidated the effects of limited concentrate feeding on growth, plasma profile, and gene expression of gluconeogenic enzymes and visfatin in the liver of Hanwoo beef calves. The purpose of this study was to test that reducing the amount of concentrate would partially be compensated by increasing the intake of forage and by altering the metabolic status. The study utilized 20 Korean native beef calves (Hanwoo; 60 to 70 d of age) divided into two groups of 10 calves each for 158 d. Control group calves received the amount of concentrate as per the established Korean feeding standards for Hanwoo, whereas calves in the restricted group only received half the amount of concentrate as per standard requirements. Good quality forage (Timothy hay) was available for ad libitum consumption to both groups. Since calves were with their dam until 4 months of age in breeding pens before weaning, the intake of milk before weaning was not recorded, however, the concentrate and forage intakes were recorded daily. Body weights (BW) were recorded at start and on 10 d interval. Blood samples were collected at start and at 50 d interval. On the final day of the experiment, liver biopsies were collected from all animals in each group. The BW was not different between the groups at all times, but tended to be higher (p = 0.061) only at final BW in control than restricted group. Total BW gain in the control group was 116.2 kg as opposed to 84.1 kg in restricted group that led to average BW gain of 736 g/d and 532 g/d in respective groups, and the differences were significant (p<0.01). As planned, the calves in the control group had higher concentrate and lower forage intake than the restricted group. The plasma variables like total protein and urea were higher (p<0.05) in control than restricted group. The mRNA expressions for the gluconeogenic enzymes such as cytosolic phosphoenol pyruvate carboxykinase (EC 4.1.1.32) and pyruvate carboxylase (EC 6.4.1.1), and visfatin measured by quantitative real-time PCR in liver biopsies showed higher expression (p<0.05) in restricted group than control. Overall, restricting concentrate severely reduced the growth intensity and affected few plasma indices, and gene expression in liver was increased indicating that restricting concentrate in the feeding schemes during early growth for beef calves is not advocated.

• 생물정신의학
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• 제19권4호
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• pp.205-210
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• 2012

Objectives The purpose of this study was to investigate clinical profile, efficacy, and safety of long-term treatment with selective serotonin reuptake inhibitors (SSRIs) in Korean autism spectrum disorders (ASDs) patients. Methods Effectiveness was assessed through a retrospective review of self-reported target symptom improvement at the last follow-up visit. Changes in illness severity and improvement were measured using the Clinical Global Impression-Severity (CGI-S) of illness and Clinical Global Impression-Improvement (CGI-I) Scales. Tolerability was assessed through a review of the reason for discontinuation of SSRI and documented adverse events. Results A total of 21 ASDs patients (aged 9 to 19 years) treated with SSRI during July 2010 to July 2011 in department of child and adolescent psychiatry of Seoul National Hospital were identified. The mean duration of SSRI treatment was 47.9 (standard deviation = 36.9) months (range 0.7-114.5), and the mean fluoxetine equivalent dosage of SSRIs was $27.1{\pm}10.8$ mg. Nineteen (90.5%) patients were using concomitant medication. We found that SSRIs were prescribed for symptoms of agitation, stereotyped behavior, aggression, depression, impulsivity and self-injury in ASDs. Ten patients (47.6%) reported improvement in their target symptom after SSRI treatment based on CGI-I scores (CGI-I ${\leq}$ 2). The side effects were reported in 5 patients (23.8%) ; vomiting (n = 2, 9.5%), excessive mood elevation (n = 1, 4.8%), insomnia (n = 1, 4.8%), somnolence (n = 1, 4.8%) and decreased appetite (n = 1, 4.8%). Self-injurious behavior was reported in one patient (4.8%). Conclusions The results of this study suggest that SSRIs may be used effectively in children and adolescents diagnosed with ASDs. However, safety issues need to be considered carefully when choosing SSRIs for treatment. Future controlled trials are needed to confirm these findings.

• 한국의료질향상학회지
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• 제11권1호
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• pp.32-45
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• 2004

Objective : The aim of this study were to measure quality of life(QOL) in liver transplant recipients, to compare QOL between living donor liver transplant recipients and cadaveric liver transplant recipients and to investigate whether SF-36 may be used as a disease-specific instrument in liver transplant recipients. Methods : We conducted a single-center cross-sectional study of 133 LT recipients ages 13 to 65 years, all of whom had had Liver Transplantation(LT) at least 1 months previously. QOL was assessed using a self-completion questionnaire consisting of the Bang Whal Ran(1991) instruments and the 36-Item Short-Form Health Survey(SF-36) health status profile measure. We investigated whether the SF-36 instrument may be used as a disease-specific instrument in LT recipients. Individual scale scores range from 0 to 100, with higher score reflecting better health. Data on demographics, clinical status at pre transplantation 1 day, post transplantation clinical status, and graft function were collected to identify predictors of post transplantation QOL. Results : Standard measures for test-retest reliability, internal consistency, and discriminant and concurrent validity were examined. The reliability of the SF-36, as measured by test-retest correlation(Pearson coefficients: 0.729, p=0.002) and by internal consistency(Cronbach's alpha: 0.9431) exceeded conventional acceptability criteria. The correlation between domain scores of SF-36 and the Bang Whal Ran(l991) was clear and logical in that the clinical characteristics of SF-36 strongly correlated with the clinical component summary score of the Bang Whal Ran(l991)(r = 0.8155, P<.01). SF-36 scale scores were compared between Cadaveric Liver Transplant recipients and Living Donor Liver Transplant recipients. Donor types of post LT did not influence HRQOL(p>0.05). 87% of the liver transplant recipients were satisfied to get LT. Satisfaction of post LT showed significantly greater HRQOL(p<0.001). Conclusion : SF-36 is found reliable and valid. This study indicates thet Donor Type did not influence HRQOL after LT. The information gained from this study will help us to better define expectations and the clinical course after liver transplantation to patients and their families.

• 한국지진공학회논문집
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• 제13권6호
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• pp.11-25
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• 2009

본 연구에서는 지진파의 푸리에 가속도스펙트럼(Fourier Acceleration Spectrum)에 기반한 계측진도 평가방법(Sokolov and Wald, 2002)을 국내에 적용하기 위해 국내 지진 MMI ${\leq}$ IV 범위에 대한 진도별 FAS 통계특성(평균과 표준편차) 모델을 기상청 발표 진도자료로 부터 도출된 65개 지진에 대한 등진도구역도(Isoseismal Maps)와 등진도구역도 상의 일관된 부지특성을 갖는 580개 수평성분 FAS 자료를 기반으로 경험적으로 도출하였다. 일관된 부지특성을 갖는 FAS는 특정 지진관측소에서 관측된 FAS를 국내 지반물성을 대표할 수 있는 D 등급관측소(연관희와 서정희, 2007)의 부지증폭특성을 갖도록 변환하여 도출하였다. 국내 지진의 MMI ${\leq}$ IV의 FAS 평균값은 로그영역에서 진도에 비례하는 선형성을 나타내었으며, 진도 IV에 대한 FAS 평균은 전 세계 모델과 유사한 특징을 보였다. 또한 진도 MMI ${\leq}$ IV의 FAS 표준편차는 진도 V 이상의 전 세계적인 모델의 표준편차 보다는 크게 평가되었으나, 진도 IV에 대한 전 세계적인 모델의 표준편차보다는 현저히 낮은 값을 나타내었다.

• Korean Chemical Engineering Research
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• 제54권5호
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• pp.612-620
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• 2016

산화 칼슘 수용액을 통해 이산화탄소를 포집하는 수성 광물 탄산화 공정은 안정적으로 이산화탄소를 고립시킬 뿐 아니라 생성물의 부가 가치를 기대할 수 있는 대표적인 CCU (Carbon Capture & Utilization) 기술이다. 이 공정의 핵심은 고체 반응물인 산화칼슘의 용해 속도를 최대로 높이는 것인데, 이를 위해 반응기 전체에 고체 반응물이 균일하게 분포되도록 혼합하는 적절한 반응기의 설계가 필요하다. 본 논문에서는 하루에 40ton의 이산화탄소 포집이 가능한 파일럿 규모의 광물 탄산화 반응기를 대상으로, 반응기의 내부 구조 설계에 따라 고체 반응물의 분산도가 어떻게 변하는지에 대해 전산 유체 역학적 모델링(Computational Fluid Dynamics (CFD) modeling)을 통해 연구하였다. 교반 탱크 반응기(stirred tank reactor) 형태를 기반으로 외부 구조는 고정한 상태에서 교반기의 종류/갯수/지름/유격/회전 속도, 칸막이의 높이/너비를 변수로 선정하여 다양한 조합의 경우(case)들을 해석하였다. 각 설계 변수에 대한 민감도를 분석함으로써 각 변수의 영향을 파악하고, 중요한 변수를 판별할 수 있었다. 동시에 고체 부피 분율(solid volume fraction)의 높이 방향 표준 편차가 0.001에 가까운 균일한 분포를 만들 수 있는 내부 설계안을 제안하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제30권9호
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• pp.1340-1349
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• 2017

Objective: This study aimed to evaluate the microbiological and cellular milk profile for the diagnosis of subclinical mastitis in female buffaloes and to assess risk factors for predisposition of the disease. Methods: Analyses were carried out by standard plate count (SPC), identification of species and antibiotic resistance, somatic cell count (SCC), electrical electrical conductivity of milk (ECM), and lactoferrin content in milk. Teat cups were swabbed to evaluate risk factors, observing hyperkeratosis, milking vacuum pressure and cleanliness of the site. Hence, 30 female buffaloes were randomly selected (15 from a group in early lactation and 15 in late lactation). Results: The most common bacteria in the microbiological examination were Staphylococcus spp., Streptococcus spp. and Corynebacterium sp. In the antibiotic sensitivity test, 10 (58.82%) of the 17 antibiotics tested were sensitive to all isolates, and resistant bacteria were Streptococcus uberis, Streptococcus dysgalactiae, Streptococcus haemolyticus, and Escherichia coli. It was observed that positive samples in the microbiological examination showed total bacterial count between $9.10{\times}10^3$ to $6.94{\times}10^6$ colony forming units/mL, SCC between 42,000 to 4,320,000 cells/mL and ECM ranging from 1.85 to 7.40 mS/cm. It was also found that the teat cups had high microbial counts indicating poor hygiene, and even faults in the cleanliness of the animals' waiting room were observed. It is concluded that values of SCC above 537,000 cells/mL and ECM above 3.0 mS/mL are indications of mammary gland infection for this herd; however, the association of these values with a microbiological analysis is necessary to more accurately evaluate the health status of mammary glands with subclinical mastitis. Conclusion: Through phenotypic characterization of bacteria involved in the samples, the genera Staphylococcus spp., Streptococcus spp., and Corynebacterimum bovis were the most prevalent in this study. Faults in environment and equipment hygienization are factors that are directly associated with mastitis.

• 전자공학회논문지CI
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• 제45권2호
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• pp.26-32
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• 2008

동영상 압축 기술은 오랜 기간 동안 연구되었으며 H.264/AVC는 최근에 사용되고 있는 동영상 압축 표준 중 가장 효율적인 동영상 압축 표준으로 알려져 있다. H.264/AVC의 베이스 프로파일에서는 무손실 압축과정으로 기존의 VLC(Variable Length Coding) 방식 대신에 압축 효율을 향상시킨 CAVLC(Context-Adaptive Variable Length Coding)라는 압축 방식을 사용한다. CAVLC 복호기는 기존의 VLC 보다 많은 VLC 표가 필요하기 때문에 하드웨어로 구현하기에는 많은 면적을 요구하게 되며 소프트웨어로 구현 시에는 표 탐색에 의해서 성능이 저하된다. 본 논문에서는 이러한 CAVLC 복호기의 소프트웨어에서의 성능 저하를 막기 위해서 VLC 표를 계층적으로 집단화하여 코드만으로 주소를 정하고 정해진 VLC 표를 한번만 참조하여 성능을 향상시키는 방법을 제안한다. 제안된 알고리즘은 C 언어로 모델링하였으며 ARM ADS1.2에서 컴파일하고 ARM9TDMI 프로세서 시스템을 Armulator를 이용하여 시뮬레이션하였다. 실험 결과, H.264/AVC 표준 참조 프로그램인 JM(Joint Model) 10.2 보다 약 80%의 수행 시간 단축을 보였으며 최근 논문에서의 산술연산 알고리즘보다 15%의 성능 향상을 보였다.

• Restorative Dentistry and Endodontics
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• 제24권1호
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• pp.222-232
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• 1999

The purpose of this study was to evaluate the effect of heated spreader on the sealing ability of lateral condensation, compared with regular cold spreader. Forty two extracted human teeth with single canal were randomly placed into 3 experimental groups, and four additional teeth were used as positive and negative controls. Each group was prepared with Ni-Ti Profile #40 using step-down technique and obturated with standardized colored gutta-percha cone by standard(cold) lateral condensation technique, warm lateral condensation technique with Endotec and hot spreader soaked in glass bead sterilizer, each with Sealapex sealer. Control groups were not obturated, but prepared. After 2 days in 2% methylene blue, the teeth were invested and made into transparent resin blocks. And then, each block was sectioned horizontally with microtome at 1, 2, 3, 4, 5 mm levels from the apex. The linear extent of dye penetration was examined with stereomicroscope at ${\times}$20 magnification. At each of 5 levels, ratio of the area of gutta-percha was obtained by calculating the area of gutta-percha to the total area of the canal. The data collected were then analyzed statistically using an analysis of variance(ANOVA) and Scheffe test. The results were as follows ; 1. All experimental groups produced the apical microleakage. 2. The mean leakage was 1.57${\pm}$0.76mm for cold spreader group, 0.86${\pm}$0.95mm for Endotec spreader group, and 0.64${\pm}$0.93mm for hot spreader group. The difference between hot spreader group and cold spreader group was statistically significant(p<0.05). 1. At the 1 mm level, the mean ratio of area of gutta-percha was 74.58${\pm}$13.15(%) for cold spreader group, 65.42${\pm}$14.62(%) for Endotec spreader group, and 80.72${\pm}$14.63(%) for hot spreader group. There was statistically significant difference between hot spreader group and Endotec spreader group(p<0.05). 2. At the 2mm level, the mean ratio of area of gutta-percha was 87.86${\pm}$11.22(%) for cold spreader group, 66.55${\pm}$14.02(%) for Endotec spreader group, and 92.93${\pm}$7.24(%) for hot spreader group. There was statistically significant difference between Endotec spreader group and other two spreader groups(p<0.05). 3. At the level 3, 4, 5 mm, there was no statistically significant difference between each group. Within the limits of the results of this experiment, warm lateral condensation technique with hot spreader soaked in a glass bead sterilizer demonstrated favorable apical sealing effect and improved density of gutta-percha mass. Thus, it is thought that this obturation technique is effective for clinical use and beneficial to reduce condensation forces, also economical and easy. Lateral condensation, Heated spreader, canal sealing, Microleakage.

• 생물환경조절학회지
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• 제24권3호
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• pp.135-146
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• 2015

본 연구는 온실에 작용하는 풍하중 산정을 위한 설계 풍속을 결정하는데 필요한 자료를 제공하기 위하여 10m 이하 높이에서의 풍속을 측정하여 풍속고도분포지수를 산정하고 변화를 분석하였다. 고도에 따른 풍속분포함수를 결정하기 위한 풍속고도분포지수를 계산하기 위해서는 $5m{\cdot}s^{-1}$ 이상의 풍속을 사용하는 것이 타당하다고 판단된다. 농촌 개활지인 부안지역의 고도에 따른 풍속변화는 지표면으로부터 풍속이 지수함수로 증가하는 우리나라의 RDC 기준과 일본의 JGHA 기준과 잘 일치하였고 풍속고도분포지수도 0.26으로 기준들에서 제시된 0.25와 거의 동일한 값을 나타내었다. 반면 군위지역의 경우는 풍속고도분포지수가 0.06으로 산정되어 지표면조도가 클수록 풍속고도분포지수가 증가하는 일반적인 변화 경향과는 반대로 나타났다. 이는 타워가 주변지대보다 약 2m 가량 더 높은 위치에 설치되었기 때문에 유선의 급격한 변화에 의한 것으로 판단된다. 따라서 일반적으로 농촌 개활지에 설치되는 온실의 설계를 위해 적용할 풍속고도분포로는 우리나라의 RDC기준과 일본의 JGHA기준에서 제시한 풍속고도분포가 가장 타당한 것으로 사료된다. 부안의 경우 오전 7시 경부터 풍속고도 분포지수가 감소하다가 오후 3시경에 최소가 된 후 다시 증가하여 24시경에 일정해지는 것으로 나타나 시간에 따른 풍속고도분포지수의 일반적인 변화경향과 잘 일치하였다. 부안지역은 형상변수가 1.51로 나타나 간척지인 부안지역의 풍속특성이 제주도 연안지역과 유사한 풍속특성을 가지고 있음을 확인하였다.