• Journal of Plant Biology
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• 제36권3호
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• pp.285-292
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• 1993

Cellular compatibility in the self-parasitism of Cuscuta australis R. Brown was studied at the ultrastructural level. The front cells of the haustorium penetrated the host stems independently grew within the host tissues and transformed into elongate, filamentous hyphae. Each hyphal cells contained a large nucleus and dense cytoplasm with abundant cell organelles. Multilamellar structures were contained in the cytoplasm and cell walls of the penetrating hyphal cells. When the hyphal cells did not yet invade the host cells, the middle lamella and the fused cellulosic cell walls of the two partners at the host-parasite interface were preserved well. As the invasion of the parasitic hyphal cells progressed, however, the middle lamella was not found at the interface and the host cell walls and plasma membranes were partially broken down. A hyphal cell penetrated deeply into the host cell had a more darkly stained cytoplasm with numerous of cell organelles. In the host cells attacked by the hyphal cells the limiting membranes of plastids were broken down and several vesicles were arrayed near the cell walls. No plasmodesmatal connections between the host and parasite cell walls were found; however, half-plasmodesmata were observed frequently on the side of the hyphal cell walls. These results suggested that the compatibility response in the self-parasitism of Cuscuta was expressed by cell walls, not by plasmodesmata, between the host and the parasite cells.

• Journal of Multimedia Information System
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• 제1권2호
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• pp.127-132
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• 2014

The transverse electromagnetic (TEM) cells are widely used for electromagnetic compatibility (EMC) testing and field probe calibrations. We propose the verification of TEM mode with statistical method using a four-port TEM cell. The verification results are compared with Normal, Rayleigh, and Gamma distribution. As a result, the 75 % quantile of the Rayleigh distribution is excellent agreement with the true quantiles for a number of calibration points.

• 대한의용생체공학회:의공학회지
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• 제10권2호
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• pp.195-202
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• 1989

Chinese Hamster Ovary( CHO) cells were cultured on the surface-modified polymers described in the previous study( "Polymer Surfaces for Cell Adhesion. 1. Surface Modification of Polymers and ESCA Analysis, " J. of KOSOMBE, Vol. 10, No. 1, 43-51, 1989). Among the physicochemical treatment methods. the chloric acid treatment was found to be the best method of rendering the polymer surfaces adhesive for CHO cells probably due to the high density of hydroxyl groups on the surface. Among the biological methods, the fibronectin treatment was best for CHO cell-compatibility probably due to specific active sites existed on the tell-binding domains of the fibronectin structure. When we compare the cell-compatibility of the chloric acid - and the fibronectin -treated PET surfaces, the number of cells attached on the surfaces were increased by 460.5 % and 559.0 % and, respectively, after 32 hr CHO cell culture, compared to that of untreated PET.eated PET.

• Journal of Chest Surgery
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• 제26권2호
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• pp.80-85
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• 1993

Synthetic and biosynthetic vascular grafts of small diameter have long been considered to be prone to thrombosis, ultimately leading to the complete graft occlusion. Endothelial cell seeding onto synthetic blood-contacting surfaces has been suggested to be an ideal means to solve this problem. This study described a culture method of bovine endothelial cells and evaluated blood-compatibility and seeding efficiency of cultured endothelial cells. Bovine pulmonary artery endothelial cells were harvested enzymatically and grown to confluence on polystyrene culture flask surfaces using established techniques. The identification of endothelial cells was made through the demonstration of expression of factor VIII R:Ag by immunofluorescent technique. To quantitate the effect of improvement in blood-compatibility of viable endothelial cells, endothelial monolayers were exposed to blood containing $\^$111/In-oxine labeled platelets. Viable endothelial monolayers retained less labeled platelets than control surfaces. The Indium-labeled endothelial cells were seeded onto three different blood-contacting surfaces of Dacron vascular graft immobilized in specially equipped wells and incubated for specific time intervals (t=15, 30, 60, 120 minutes). Longer incubation times showed improved cell adherence in collagen-coated and fibrin-coated Dacron vascular graft groups. However in untreated Dacron grafts, no direct relationship was observed between incubation time and endothelial cell seeding efficiency. This may be due to leakage of endothelial cells through porosity of Dacron grafts in this in-vitro experimental condition.

• 한국ITS학회 논문지
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• 제6권3호
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• pp.122-137
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• 2007

본 논문은 주파수 자원을 효율적으로 이용하기 위하여 무선통신 업무가 인접 대역 혹은 동일 대역에 존재하는 경우 몬테 카를로 시뮬레이션 방법을 이용하여 양립성을 분석하였다. 간섭 시나리오를 설정하면 간섭원과 피 간섭원간의 간섭 확률을 몬테 카를로 방법으로 계산한 후 이를 미리 설정된 최대 허용 간섭 확률과 비교하여 활성화 간섭원 밀도, 간섭원 대역폭, 피 간섭원의 셀 반경, 간섭원과 피간섭원 사이의 거리, 충격 계수에 따라 양립 여부를 판단하였다. 이 때 전파 모델은 free space 모델, extended Hata 모델로 가정하였다.

• 폴리머
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• 제35권3호
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• pp.189-195
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• 2011

조직 형성을 위한 생리학적 환경을 제공하는 새로운 생활성 지지체의 디자인은 생체재료 연구에서 중요한 분야이다. 본 연구에서는 3차원적 실크/PLGA 지지체의 물성평가를 위해 압축강도, 수분친화도, SEM 분석을 하였으며, 세포친화성 평가를 위해 RAW 264.7과 NIH/3T3의 부착, 증식 및 표현형유지와 염증반응에 미치는 영향을 조사하였다. 지지체는 용매 캐스팅/염 추출법으로 제조하였고, 압축강도, 수분친화도 면에서 실크 함량이 20 wt%에서 우수함 확인했으며, 표면의 거침도활 높여 세포부착에 긍정적인 구조임을 확인하였다. 세포친화성 분석 결과 실크함량이 20 wt%인 실크/PLGA 지지체에서 높은 초기부작도 및 증식률을 보였으며, 실크함량이 20 wt%에서 염증반응이 눈에 띄게 감소함을 확인하였다. 조직공학적 응용에 실크/PLGA 지지체가 유용할 것이라 판단하였다.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1989년도 춘계학술대회
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• pp.1-3
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• 1989

We have treated polymer surfaces such as polyethylene, polystyrene and polyester by various physicochemical and biological surface modification methods to be suitable for cell adhesion. The physicochemical methods we used were $O_2$ plasma discharge, corona discharge, sulfuric acid and chloric acid treatments. For the biological treatments, blood proteins such as plasma protein, serum protein and fibronectin were adsorbed onto the polymer surfaces. Chinese Hamster Ovary (CHO) cells were cultured on the surface-modified polymers and the cell-compatibility of those surfaces were compared. The chloric acid and fibronectin treatments were found to be the best methods of rendering the polymer surfaces adhesive for CHO cells.

• 폴리머
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• 제24권6호
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• pp.877-885
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• 2000

본 연구에서는 폴리락타이드 (PLA), 폴리글리콜라이드 (PGA) 그리고 이들의 공중합체인 PLGA 필름을 염소산 혼합용액 [70% 과염소산 (HClO$_4$)/포타슘 클로레이트 (KClO$_3$) 포화 수용액, 3 : 2]으로 처리하여 표면의 젖음성과 세포적합성을 증가시켰다. 표면 처리된 고분자의 표면을 물접촉각 측정과 ESCA, SEM으로 특성결정하였다. 염소산 처리된 PLA, PGA, 및 PLGA의 표면 젖음성은 처리시간이 증가함에 따라 증가되었고 이들 고분자 필름은 기존의 에탄을 전처리와 달리 건조 후에도 친수성 표면을 유지하였다. 세포 점착실험은 섬유아세포를 염소산 처리된 필름의 표면에서 1일 및 2일 배양하였고 표면의 젖음성이 증가함에 따라 세포의 점착도 우세하였다. 결론적으로 본 연구에서는 표면의 젖음성은 세포의 점착과 증식 거동에 중요한 역할을 한다는 것을 증명하였다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2005년도 추계종합학술대회
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• pp.917-919
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• 2005

전자파장해${\cdot}$내성측정 대용시험장인 GTEM셀에 대해 시험장내 전자장에 대한 전파 전달특성을 확인하고, OATS 시험장과의 상관성을 규명하도록 시뮬레이션을 하였다. 이를 통해 시험장의 구조적 문제점을 판단하고, 유효성을 확보하여 GTEM셀을 자체 제작하여 연구에 활용하였다.

• International Journal of Internet, Broadcasting and Communication
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• 제7권2호
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• pp.130-136
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• 2015

In this paper, we analyzed the adjacent channel interference of the LTE band 40 defined by 3GPP on the WLAN system based on the Monte-Carlo method, and found the guard band required for compatibility between the two systems. This study have a difference compared to the previous studies about cell radius was determined using Extended Hata Model considering practical environment, interference protection distance related to guard band, and the spectrum emission mask improvement effect for minimizing the interference. Simulation results, for no channel interference compatibility of LTE and WLAN for mobile satellite wireless package system, we can find the need 15MHz guard band at specified spectrum emission mask and 10MHz guard band at assumed spectrum emission mask.