• Journal of Periodontal and Implant Science
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• 제25권3호
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• pp.487-496
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• 1995

Previous studies have demonstrated that not all A. actinomycetemcomitans produced significant level of leukotoxic factor and its leukotoxicity have associated with serotype and genetic variation. Our aim was to investigate on the interrelationship between serotype and leukotoxicity of an A. actinomycetemcomitans consisting of 13 clinically well characterized. Korean isolates and to evaluate if particular virulent clonal types of A. actinomycetemcomitans are associated with periodontal disease. For this study, 13 strains of A. actinomycetemcomitans from 6 patients with periodontal disease were isolated and identified by using a selective medium(tryptic soy agar supplemented with 10% serum, $75{\mu}g$ of bacitracin and $5{\mu}g$ of vancomycin per ml) in 10% C02 incubator for 3days with routine Gram staining, colony morphology and biochemical test..For serotyping, antisera were prepared from reference strains of 5 serotypes. (ATCC 29523,Y4, SUNY aB 67, IDH 781, IDH 1705) and then ammonium sulfate precipitation, immunoabsorption and indirect immunofluoroscent procedures were done. For analysis of leukotoxicity, sonic extract of A. actinomycetemcomitans exposed to PMN, and trypan blue was stained for counting the cell viability. Finally Southern blot analyses of genomic DNA digested with the restriction enzyme Tag I was done and the Southern blots were hybridized with the 530bp fragment, termed delta 530, originating from the ltx promoter of strain 652 and deleted from strain JP2. Also ltxA-3.1 and SC2 probe from strain JP2 were hybridized with genomic DNA fragments. Results reveal that strains isolated showed approximately equal proportions of 3 serotypes(b, d, e) and serotype b was not detected. 2 patients harbored 2 different serotypes in the same disease site. The prevalence of leukotoxic strain was 23% and there was no relationship between serotype, leukotoxicity and clinical observations. Especially virulent clonal types of Actinobacillus actinomycetemcomitan (JP2 strain) could not found. Further studies are necessary on the genetic polymorphism of leukotoxin and its relations to clinical status.

• 생명과학회지
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• 제17권8호통권88호
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• pp.1034-1038
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• 2007

하이퍼리신(Hypericin, HyH)은 예로부터 성 요한의 풀(St. John's Wort)로 널리 알려져 있는 서양고추나물(Hypericum perforatum)에서 추출되는 약리성분이다. 서양고추나물은 국내에서는 자생하지 않으나 같은 속의 고추나물(H. erectum) 등이 이속에 속하며 우리나라에 자생한다 . 고추나물을 조직배양으로 RNA를 추출하고 cDNA를 합성한 후 Hyp 유전자를 추출하여 서열화한 결과, 전체 크기는 732 bp로 나타났으며 서양고추나물의 HyH-1과 거의 99.8% 서열 일치를 나타내었다. 이 서열의 152개 아미노산 역시 서양고추나물의 항산화효소와 98% 일치하였으며 자작나무와 능금속 식물에서 유발되는 알레르기 유발유전자와 약 60% 일치를 나타내었다. 본 연구 결과 우울증치료제로 사용되는 하이퍼리신 추출에 우리나라 자생종인 고추나물이 이용될 수 있을 것으로 사료된다.

• 한국의류학회지
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• 제33권11호
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• pp.1806-1816
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• 2009

This study analyzes the efficiency of a solar cell attached to an air circulation jacket. A commercially available silicon solar panel was selected and attached at four spots where the body angle was $40-60^{\circ}$ and voltage ($V_{oc}$, V), current ($I_{sc}$, A), and output power (P, W) were measured to determine the efficiency. The solar panel was applied to the outer jacket that operates with two fans to increase the convection that lowers the body temperature. The heavy work of standing, walking, and sweeping of a street sweeper was simulated in the field test. The microclimate within the jacket (with or without a fan) was measured and the subjective thermal, humidity, and comfort sensations were surveyed. SPSS 12.0 statistical package was used for a t-test and Wilcoxon signed-rank test. The results show that the highest efficiency of the solar cell was at the incident angle of $60^{\circ}$ in terms of voltage, current and output power distribution. The microclimate temperature of the air circulation jacket decreased significantly with the high power of the fan and subjects felt cooler than the jacket with a fan at the incident angle of $60^{\circ}$. Air circulation jackets operated by a silicon solar panel showed a significant cooling effect on the wearers.

• 한국전자파학회논문지
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• 제9권6호
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• pp.802-812
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• 1998

고전압 발/ 변전소의 근무자나 송전선 작업자 및 주변거주자가 전계 노출에 안전해야 함은 중요한 일이다. 본 논문에서는 복잡하고 계산시간이 많이 소요되는 인체의 3차원 유도전류를 계산하기 위해 전압원(송전선 로)의 효과적인 모델링 기법을 사용하여 전압원과 피유도체를 분리하지 않고 직접 3차원 정전용량을 구함으 로써 불평등 전계하의 임의의 3차원 공간상에서도 인체에 미치는 유도전류 해석이 가능한 장접을 갖도록 하 였다. 사례연구로 본 연구에서 제안한 알고리즘을 765 kV급 초고압 송전선로에 적용하여 인체 유도 안전 성을 평가한 결과 765 kV 송전선에서 인체의 단락전류는 인체의 위치에 따라 0.3 mA에서 6.8 mA로 분포 되었다. 특히, 송전선로에서 활선 작업시 단락전류 $I_{sc}$의 크기는 ANSI 허용기준인 5 mA를 념을 수 있어 활 선 작업시 작업자의 전계의 방호 대책을 위해서는 도전물질로 구성된 보호복이 필요함을 알 수 있었다.

• 전기학회논문지
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• 제58권12호
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• pp.2446-2452
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• 2009

A Ceramic Metal-halide lamp is achieved by adding multiple metals to a basic mercury discharge. Because the vapor pressure of most metals is very much lower than mercury itself, metal-halide salts of the desired metals, having higher vapor pressures, are used to introduce the material into the basic discharge. The metal compounds are usually polyatomic iodides, which vaporize and subsequently dissociate as they diffuse into the bulk plasma. Metals with multiple visible transitions are necessary to achieve high photometric efficiency and good color. Compounds of Sc, Dy, Ho, Tm, Ce, Pr, Yb and Nd are commonly used. The maximum visible efficacy of a Ceramic Metal Halide lamp, under the constant of a white light source, is predicted to be about 450lm/W. This is controlled principally by the chemical fill chosen for a particular lamp. Current these lamps achieve 130lm/W and these life time are the maximum 16,000[hr]. So factors of performance lower are necessary to improve lamp performance. In this paper, we analyzed factors of performance lower by accelerated deterioration test. The lamp was operated with short duration turn-on/turn-off procedure to enhance the effect due to electrode sputtering during lamp ignition. The tested lamp that was operated with a longer turn-on/off(20/20 minutes) showed blackening, changed distance between electrodes and lowered color rendering & color temperature by losses of Dy at 421.18nm, I at 511nm, T1 at 535nm and Na at 588nm compared with the new lamp.

• Asian-Australasian Journal of Animal Sciences
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• 제18권4호
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• pp.458-462
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• 2005

The study was aimed at detecting polymorphism of the fifth intron in lipoprotein lipase (LPL) gene and analyzing association between the polymorphism and productive traits. A pair of primers was designed for amplifying the fifth intron. Sequence analysis indicated that a G1171C substitution existed in Large White breed. The mutation was detected by PCR-AfaI-RFLP. Polymorphism analysis in a pig resource family showed that there existed significant effects on carcass and meat quality traits. Thoraxwaist fat thickness of BB genotype was significantly higher (14.2%, p<0.05) than that of AA on carcass traits, while BB genotype was significantly lower (3.6% p<0.01, 4.1% p<0.01; 2.3% p<0.01, 1.9% p<0.01; 1.8% p<0.01, 1.4% p<0.05) than AA and AB genotype in pH of m. Longissimus Dorsi (LD), m. Biceps Femoris (BF), m. Semipinali Capitis (SC). The allelic frequencies were also significantly different between indigenous Chinese breeds and exotic breeds. Data analyzed revealed that the mutation locus affected production traits mostly by additive effects. Based on these results, it is necessary to do more studies on LPL gene before making the LPL locus into the application of marker-assisted selection (MAS) programs.

• 미생물학회지
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• 제36권1호
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• pp.64-68
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• 2000

Agrocybe cylindracea으로부터 분리 배양한 균사체 배양액을 이용하여 균사체내 다당류(IP)와 균사체외 다당류(EP)를 분리하고, 동물실험을 통한 각 다당류의 면역증강활성에 관해 실험을 실시하였다. 탐식능에 대한 실험결과, IP와 EP 모두는 복강 침출 세포(PEC)에서 대조군에 비해 6.6-50%, 말초 임파구(ML)에서 67-167%, 비장(SP)에서 16-90%의 전반적으로 높은 탐식능을 나타냈다. 또한 항체 생성능 측정을 위한 plaque forming cell(PFC)와 rosette forming cell(RFC)의 실험결과에서 볼 때, PFC형성능은 대조군에 비해 EP투여 II군에서 46-50%, IP투여 I군에서 49-70%의 활성증가를 나타내었다. 또한 RFC형성능은 대조군에 비해 IP투여 I군에서 91%의 증가를, EP투여 I군에서 33%, EP투여 II군에서 43%의 활성증가를 나타내어 높은 항체생성이 기대되었다. Mitogen 활성은 농도 의존적으로 세포 증식능을 보였으며, IP와 EP를 비교할 때, EP는 IP에 비해 약2.5배의 세포증식 활성을 보였다.

• Current Photovoltaic Research
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• 제2권3호
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• pp.103-109
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• 2014

Highly efficient hydrogenated nanocrystalline silicon (nc-Si:H) thin-film solar cells were prepared on flexible stainless steel substrates using plasma-enhanced chemical vapor deposition. To enhance the performance of solar cells, material properties of back reflectors, n-doped seed layers and wide bandgap nc-SiC:H window layers were optimized. The light scattering efficiency of Ag back reflectors was improved by increasing the surface roughness of the films deposited at elevated substrate temperatures. Using the n-doped seed layers with high crystallinity, the initial crystal growth of intrinsic nc-Si:H absorber layers was improved, resulting in the elimination of the defect-dense amorphous regions at the n/i interfaces. The nc-SiC:H window layers with high bandgap over 2.2 eV were deposited under high hydrogen dilution conditions. The vertical current flow of the films was enhanced by the formation of Si nanocrystallites in the amorphous SiC:H matrix. Under optimized conditions, a high conversion efficiency of 9.13% ($V_{oc}=0.52$, $J_{sc}=25.45mA/cm^2$, FF = 0.69) was achieved for the flexible nc-Si:H thin-film solar cells.

• 식물분류학회지
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• 제47권1호
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• pp.11-22
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• 2017

Prangos fedtschenkoi (Regel et Schmalh.) Korovin (Apiaceae) is an endemic species for mountainous Middle Asia, which is both a rare and useful plant. Organic extractions from this species are being used in pharmaceutics and cosmetology. In recent years, P. fedtschenkoi distribution area has considerably decreased, presumably, resulting from human activities such as agriculture, construction works, overgrazing and collection from wild for pharmaceutic purposes. Six populations were found in Uzbekistan and their genetic divergence and differentiation were studied with 10 inter-simple sequence repeat (ISSR) markers, selected out of 101. Totally 166 amplified ISSR fragments (loci) were revealed, of which 164 were polymorphic. Relatively moderate level of polymorphism was found at population level with polymorphic bands ranging from 27.71% to 47.59%. Mean P = 39.05%, $N_a=1.40$, $N_e=1.25$, S.I. = 0.21, and $H_e=0.14$ were revealed for all loci across six populations. AMOVA showed higher variation among populations (62%) than within them (38%). The Bayesian model determined 5 clusters, or genetic groups. The posteriori distribution of the Theta II estimator detected full model identifying high inbreeding, intensified by low gene flow (Nm = 0.3954). Mantel test confined population 6 as distinct cluster corresponding to geographic remoteness (R = 0.5137, $p{\leq}0.005$). Results were used as the bases for developing conserve measures to restore populations.

• 전자공학회논문지SC
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• 제47권4호
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• pp.7-14
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• 2010

유한 상태 머신으로 표현되는 비동기 머신의 안정 상태 동작은 피드백 제어를 통해서 원하는 목적에 맞게 교정될 수 있다. 본 논문에서는 불확실한 상태 천이를 가지는 입력/상태 비동기 머신을 위한 상태 피드백 제어기를 제안한다. 비동기 머신은 결정적인 동작 특성을 가지고 있으나 모델 불확실성, 내부 고장 등으로 인해서 일부 영역의 상태 천이 함수가 불확실하다. 교정 제어의 목적은 불확실한 상태 천이를 고려하면서 머신의 폐루프 동작이 주어진 정상적인 모델 동작의 부분 집합이 되도록하는 일이다. 또 제어기는 실제 교정 동작을 수행하면서 획득하는 머신의 정확한 상태 천이를 그 다음 제어 동작에 반영한다. 즉 학습을 통해서 폐루프 시스템이 이룰 수 있는 모델의 부분 동작의 범위가 더 확대된다. 사례 연구를 제안된 제어기의 설계 과정을 예시한다.