• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 추계학술대회 논문집 학회본부
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• pp.196-198
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• 1994

The dielectric and electrical properties of $Pb(Mg_{1/3}Nb_{2\3})O_3-PbTiO_3-BaTiO_3$ have been investigated. Perovskite crystalline phase of the specimens are confirmed by XRD at $1270^{\circ}C$. The curie temperature is around $40^{\circ}C$ with the amount of $BaTiO_3$ and $PbTiO_3$. Every specimens shows the slim loop hysteresis curves which is electrostrictive characteristic. The strain vs. applied voltage characteristics exhibits nonlinear relationship, and the specimen of 0.85PMN-0.125PT-0.025BT shows the largest strain.

• Korean Chemical Engineering Research
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• 제52권2호
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• pp.205-208
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• 2014

본 논문에서는 유기전자소자의 반도체 물질로 많이 사용되는 poly(9,9-dioctylflurorene) (PFO), poly(9,9-dioctylfluorene-co-benthiadiazole) (F8BT), (regioregular poly(3-hexylthiophene) (P3HT)를 기반으로 하는 균일한 크기와 특성을 가지는 고분자 나노와이어를 AAO 템플레이트를 이용하여 대량으로 제작하였다. 제작된 나노와이어는 결점이 없이 깨끗한 표면을 보였으며, 약 250~300 nm의 지름과 ${\sim}30{\mu}m$의 일정한 길이를 가지고 있었다. 나노와이어들은 스프레이 분사 방법을 통하여 유리 기판 위에 균일하게 분사할 수 있었으며, PFO와 F8BT 나노와이어의 경우 UV 빛의 조사하에 각각 나노와이어의 전체에 걸쳐서 왜곡없이 밝은 yellow와 blue luminescence를 보였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1992년도 추계학술대회 논문집
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• pp.42-45
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• 1992

In this study, the structural, dielectric and electrical properties of $0.85Pb(Zn_{1/3}Nb_{2/3})O_3-0.1BaTiO_3-0.05PbTiO_3$ ceramics were investigated with respect to the variations of $La_2O_3$ addition amount. The specimen with 0.2 [wt%] $La_2O_3$ addition amount, which has the coupling constants with the value of $k_p$=44.8[%]. $k_{31}$=25.4[%] and the piezoelectric constant with $d_{31}=100{\times}10^{-12}$[C/N] respectively, exhibits the relatively good values in the applications of electrostriction actuators.

• Asian Pacific Journal of Cancer Prevention
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• 제16권15호
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• pp.6651-6661
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• 2015

Breast cancer is a global health concern and is a major cause of death among women. In Oman, it is the most common cancer in women, with an incidence rate of 15.6 per 100,000 Omani females. Various anticancer remedies have been discovered from natural products in the past and the search is continuing for additional examples. Cytotoxic natural compounds may have a major role in cancer therapy either in potentiating the effect of chemotherapy or reducing its harmful effects. Recently, a few studies have reported advantages of using crude camel milk in treating some forms of cancer. However, no adequate data are available on the lyophilised camel's milk responsibility for triggering apoptosis and oxidative stress associated with human breast cancer. The present study aimed to address the role of the lyophilised camel's milk in inducing proliferation repression of BT-474 and HEp-2 cells compared with the non-cancer HCC1937 BL cell line. Lyophilized camel's milk fundamentally repressed BT-474 cells growth and proliferation through the initiation of either the intrinsic and extrinsic apoptotic pathways as indicated by both caspase-3 mRNA and its action level, and induction of death receptors in BT-474 but not the HEp-2 cell line. In addition, lyophilised camel's milk enhanced the expression of oxidative stress markers, heme-oxygenase-1 and reactive oxygen species production in BT-474 cells. Increase in caspase-3 mRNA levels by the lyophilised camel's milk was completely prevented by the actinomycin D, a transcriptional inhibitor. This suggests that lyophilized camel's milk increased newly synthesized RNA. Interestingly,it significantly (p<0.003) repressed the growth of HEp-2 cells and BT-474 cells after treatment for 72 hours while 24 hours treatment repressed BT-474 cells alone. This finding suggests that the lyophilised camel's milk might instigate apoptosis through initiation of an alternative apoptotic pathway.

• Journal of Ecology and Environment
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• 제33권2호
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• pp.165-173
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• 2010

Soil respiration ($R_S$) is a critical component of the annual carbon balance of forests, but few studies thus far have attempted to evaluate empirical regression models in $R_S$. The principal objectives of this study were to evaluate the relationship between $R_S$ rates and soil temperature (ST) and soil water content (SWC) in soil from a cool-temperate deciduous broad-leaved forest, and to evaluate empirical regression models for the prediction of $R_S$ using ST and SWC. We have been measuring $R_S$, using an open-flow gas-exchange system with an infrared gas analyzer during the snowfree season from 1999 to 2001 at the Takayama Forest, Japan. To evaluate the empirical regression models used for the prediction of $R_S$, we compared a simple exponential regression (flux = $ae^{bt}$Eq. [1]) and two polynomial multiple-regression models (flux = $ae^{bt}{\times}({\theta}{\nu}-c){\times}(d-{\theta}{\nu})^f:$ Eq. [2] and flux = $ae^{bt}{\times}(1-(1-({\theta}{\nu}/c))^2)$: Eq. [3]) that included two variables (ST: t and SWC: ${\theta}{\nu}$) and that utilized hourly data for $R_S$. In general, daily mean $R_S$ rates were positively well-correlated with ST, but no significant correlations were observed with any significant frequency between the ST and $R_S$ rates on periods of a day based on the hourly $R_S$ data. Eq. (2) has many more site-specific parameters than Eq. (3) and resulted in some significant underestimation. The empirical regression, Eq. (3) was best explained by temporal variations, as it provided a more unbiased fit to the data compared to Eq. (2). The Eq. (3) (ST $\times$ SWC function) also increased the predictive ability as compared to Eq. (1) (only ST exponential function), increasing the $R^2$ from 0.71 to 0.78.

• Journal of Korean Dental Science
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• 제6권1호
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• pp.13-21
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• 2013

Purpose: To report the successful results of using chin bone graft and autogenous tooth bone graft material (AutoBT) in alveolar cleft patients. Materials and Methods: Five patients with alveolar cleft defects underwent alveolar bone grafting. Three patients were treated using chin bone graft, and the other two patients underwent AutoBT graft. After implant site development using chin bone graft in the fi rst three cases, endosseous implant restorations were placed. In case #4 and 5, AutoBT graft material was placed to guide the normal eruption of partially impacted maxillary right canine and to the upper docking site after distraction osteogenesis. Result: Successful implant restorations with closure of the oronasal fistula were achieved in alveolar cleft defect reconstruction using either chin bone graft (Case #1, 2, 3) or AutoBT graft material (Case #4, 5). Case #4 showed enlarged follicle of the right maxillary canine, indicating a normal eruption guide pattern. Conclusion: Both chin bone graft and AutoBT graft showed favorable outcomes in reconstructing alveolar cleft defects. Autogenous tooth bone graft opens up the possibility of avoiding harvesting autogenous bone graft with complications and morbidities.

• 대한수의학회지
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• 제42권2호
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• pp.277-282
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• 2002

This study was conducted to investigate the influences of the rope and the tipping chute restraints on body temperature (BT) and heart rate (HR) as acute response for stress caused by restraining for diagnasis and treatment in cattle. Both parameters were recorded by active biotelemetry. In addition cortisol concentration in blood was analyzed as a indicator for stress response. Twelve cattle were divided into two groups based on hydraulic power, the rope restraint group and the tipping chute restraint group. BT and HR were measured at -30 (base), 0, 10, 20, 30, 40, 50, 60, 90, 120, and 180 minutes, including restraint period from 0 to 30 minutes during the experiment. The results obtained in this study was summarized as follows: 1. BT of the rope restraint group was increased ($39.8{\pm}0.3^{\circ}C$) until 20 min after restraint stress for 30 min, and then maintained with high values to the end of experiment. In the tipping chute restraint group, the BT was increased ($39.6{\pm}0.3^{\circ}C$) until the end of the restraint period, but then showed decrese until the end of experiment. 2. HR of both groups was maximized at the beginning of the restraint stress (P<0.05), and then it was decreased gradually but in the tipping chute restraint group showed increase again at the end of the reatraint stress (P<0.05). 3. The cortisol level of the rope restraint group was increased significantly ($9.72{\pm}5.09{\mu}g/d{\ell}$) until 30 min after the end of the restraint stress (P<0.05) and then decreased, but in the tipping chute restraint group showed great increase ($4.68{\pm}1.56{\mu}g/d{\ell}$) at the end of the restraint stress (P<0.05) and then decreased while the tipping chute restraint group was significantly lower than the rope restraint group 30 min after the restraint stress (P<0.05). In conclusion, this study suggests that the tipping chute restraint produces less response to physical stress than the rope restraint but the time for diagnasis and treatment should be shortened when using the tipping chute restraint.

• 전기전자학회논문지
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• 제3권2호
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• pp.161-167
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• 1999

표준 2-poly CMOS 공정을 이용하여 3-입력 neuron-MOSFET의 인버터와 증가형 소자를 사용한 3비트 D/A 변환기를 설계 제작하였다. Neuron-MOSFET를 사용한 인버터의 전압전달 특성곡선과 잡음여유를 일반 CMOS 인버터와 같은 방법으로 측정분석하였다. 결합계수가 전압전달 특성곡선과 잡음여유에 미치는 영향을 이론적으로 계산하여 neuron-MOSFET 인버터의 게이트 산화층 두께와 입력게이트 레이아웃에 대한 설계 가이드라인을 설정하였다. 입력게이트 중 하나를 제어게이트로 사용하므로 offset전압이 없는 neuron-MOSFET D/A 변환기를 설계 제작할 수 있었다.

• 산업식품공학
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• 제13권3호
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• pp.183-189
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• 2009

혈압저하작용, 이뇨기능 등의 다양한 생리활성을 나타내는 $\gamma$-amino butyric acid(GABA)를 고농도로 생산하는 유산균인 Lactobacillus sakei B2-16을 이용하여 GABA의 산업적 생산 배지를 연구하였다. L. sakei B2-16의 최적 상용 배지는 Lactobacilli MRS 배지였으며, Lactobacilli MRS 배지에 1% mono sodium glutamate(MSG)를 첨가하고, L. sakei B2-16을 배양했을때 MSG의 99.3% 는 GABA로 전환되었다. MRS 배지를 기본으로 최적 배지조성을 검토한 결과, 탄소원으로 4% sucrose와 질소원으로 1% yeast extract를 첨가하였을 때 균체 증식과 GABA 생산량이 가장 우수하였다. 산업적 배지를 확립하기 위하여 미배아를 온수 추출하여 얻은 추출액 배지에 L. sakei B2-16을 배양한 결과, 7%의 MSG를 100% GABA로 전환시켰으며, 미배아 추출액을 이용한 배지는 산업적 생산용 배지로의 응용이 기대된다.

• Journal of Chest Surgery
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• 제31권10호
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• pp.952-963
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• 1998

연구배경 : 체외 순환으로 인한 지혈 기전의 심각한 손상은 술후 과다 출혈을 일으켜 환자의 생명을 위협하고, 대량 수혈에 따른 부작용과 재수술의 우려마저 증가시킬 수 있다. 특히, 심장 수술동안 섬유소 용해계의 활성화와 혈소판의 숫적, 기능적 변화가 술후 상당 시간동안 출혈의 원인이 된다고 보고하고 있다 대상 및 방법 : 본 연구는 체외 순환 동안 및 그 후에 있어, 체외 순환에 의한 섬유소 용해계의 활성화를 포함한 다양한 혈액학적 변화를 조사하고, 이러한 변화들이 술후 비외과적 출혈의 정도와 어떤 상관성이 있는가를 규명하기위해 체외 순환을 실시할 성인 환자 20명을 대상으로 전향적으로 계획되었다. 혈소판 수, 섬유소원 및 plasminogen 농도, FDP, D-dimer, BT, aPTT, PT와 같은 혈액학적 변수의 측정을 위해 수술동안 또는 술후 시기에 혈액을 연속적으로 채취하였다. 출혈량은 흉부 삽관을 통한 배출량을 술후 3, 6, 12, 24, 48시간의 양과 총혈액량을 각각 측정하였다. 결과 : 연구 결과를 요약하면 다음과 같다:혈소판 수는 체외 순환으로 인해 급격히 감소되었다 (p<0.01). 총 체외 순환 시간이 길수록 혈소판 수의 감소률은 더 높았으며 (r=0.55, p=0.01) 술후 7일이 되어서야 비로소 술전치에 근접하였다. 체외 순환동안 FDP와 D-dimer의 농도가 의미있게 증가하였고 (p<0.0001), 섬유소원 및 plasminogen 농도 둘 다 서로간에 상관성을 보이면서 감소하였다 (r=0.57, p<0.01). 술후 2hr-BT, 2hr-PT, 2hr-aPTT 모두 술전치에 비해 유의하게 연장되었다(각각 p<0.05, p<0.0001, p<0.0001). 술후 총 출혈량과 환자의 연령, 대동맥 차단 시간, 체외 순환 시간은 각각 양의 상관관계 (positive correlation)가 있었다. 술전 기준치 혈소판 수와 술후 3시간 출혈량, 체외 순환 종료시의 혈소판 수와 술후 3시간, 6시간 및 총 출혈량 그리고 술후 1일의 혈소판 수와 48시간 출혈량 사이에는 각각 음의 상관관계 (negative correlation)가 있었다. 술후 2hr-aPTT는 술후 6시간 및 48시간대의 출혈량에 상관성이 있었고 (r=0.53, p=0.02) 술후 2hr-PT는 48시간 출혈량과 각각 양의 상관성이 있었으나 (r=0.43, p=0.05). 이 두가지 변수와 총 출혈량 간에는 상관성이 없었고, 술후 2hr-BT와 술후 출혈량 사이에도 유의한 상관성을 발견하지 못하였다. 결론 : 이상의 관찰 결과들은 체외 순환이 섬유소 용해계의 활성화와 혈소판 수의 심한 감소를 포함한 다양한 혈액학적 변화를 유도하고 환자의 연령, 혈소판 수, 대동맥 차단 시간, 체외 순환 시간, 술후 PT 및 aPTT와 같은 다인적 상황들이 술후 출혈에 영향을 미친다는 점들을 시사하고 있다. 본 연구 결과들은 체외 순환에 따른 지혈적 손상에 관한 이해와 술후 출혈을 감소시키기 위한 기초 자료로 활용 가능하리라 사료된다.