• 한국결정성장학회지
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• 제15권6호
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• pp.260-262
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• 2005

Thickness optimization of heavily doped p-type seeding layer was studied to improve performance of thin film silicon solar cell. We used liquid phase epitaxy (LPE) to grow active layer of $25{\mu}m$ thickness on $p^+$ seeding layer. The cells with $p^+$ seeding layer of $10{\mu}m\;to\;50{\mu}m$ thickness were fabricated. The highest efficiency of a cell is 12.95%, with $V_{oc}=633mV,\;J_{sc}=26.5mA/cm^2$, FF = 77.15%. The $p^+$ seeding layer of the cell is $20{\mu}m$ thick. As thicker seeding layer than $20{\mu}m$, the performance of the cell was degraded. The results demonstrate that the part of the recombination current is due to the heavily doped seeding layer. Thickness of heavily doped p-type seeding layer was optimized to $20{\mu}m$. The performance of solar cell is expected to improve with the incorporation of light trapping as texturing and AR coating.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 춘계학술대회
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• pp.168-171
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• 2005

Thickness optimization of heavily doped p-type seeding layer was studied to improve performance of thin film silicon solar cell. We used liquid phase epitaxy (LPE) to grow active layer of $25{\MU}m$ thickness on p+ seeding layer. The cells with p+ seeding layer of $10{\mu}m\;to\;50{\mu}m$ thickness were fabricated. The highest efficiency of a cell is $12.95\%$, with Voc=633mV, $Jsc=26.5mA/cm^2,\;FF=77.15\%$. The $P^+$ seeding layer of the cell is $20{\mu}m$, thick. As thicker seeding layer than $20{\mu}m$, the performance of the cell was degraded. The results demonstrate that the part of the recombination current is due to the heavily doped seeding layer. Thickness of heavily doped p-type seeding layer was optimized to $20{\mu}m$. The performance of solar cell is expected to improve with the incorporation of light trapping as texturing and AR coating.

• Investigative Magnetic Resonance Imaging
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• 제21권2호
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• pp.119-124
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• 2017

Chromophobe renal cell carcinoma (RCC) is an uncommon subtype of RCC having a better prognosis than clear cell RCC. Although there are several reports of seeding metastasis of RCC after biopsy, seeding metastasis of chromophobe RCC after surgical resection has seldom been reported. Here, we describe a case of multiple seeding metastases in the abdomen and pelvis 78 months after robot-assisted laparoscopic partial nephrectomy, without prior history of biopsy for chromophobe RCC in the right kidney. As magnetic resonance imaging (MRI) of the pelvic mass showed a similar appearance to the primary renal mass and displayed separate margins with the rectum and prostate gland, we were able to make a diagnosis before pathologic confirmation.

• 생물환경조절학회지
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• 제16권1호
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• pp.62-66
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• 2007

시금치 수경재배에 적합한 육묘배지 선발과 육묘 플러그 트레이 크기, 육묘 플러그 트레이 셀(cell)당 종자수 조절로 안정 공정 육묘생산을 위한 실험을 수행하였다. 수경재배 육묘배지에 따른 입모율과 유묘의 생육특성을 조사한 결과 입모율은 보습성이 좋은 입상암면 >입상암면+펄라이트 혼용배지>코코피트>펄라이트>우레탄 스펀지 순으로 나타나 우레탄 스폰지의 입모율이 가장 낮았다. 육묘 플러그 트레이 셀당 종자수에 따른 엽 면적은 종자수가 많을수록 적어지고, 셀당 생체중은 2립(12.5g)에 비해 4립(33.9g)이 무거웠다. 따라서 셀당 종자수가 적으면 식물체 1개 체중은 증가되지만 전체 셀당 생체중은 감소되는 경향을 나타내었다. 수량은 셀당 2립 파종 $10,200kg{\cdot}ha^{-1}$ 비해 4립 파종 $14,910kg{\cdot}ha^{-1}$으로 46% 증가되었다.

• 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.

• Journal of Microbiology and Biotechnology
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• 제14권4호
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• pp.707-714
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• 2004

How to improve the cell culture method on scaffolds is important in the tissue engineering fileld. In this study, we optimized seeding and culture methods to vascular smooth muscle cells (VSMCs) on biodegradable polymer scaffold. The primary culture of VSMCs obtained from canine external jugular vein was accomplished by applying the explant-derived method. The primary cultured VSMCs were seeded into scaffolds and then cultured by using various different methods; static or dynamic seeding, static or dynamic culture. The difference in proliferative response of VSMCs was analyzed with an alamar blue assay. Cell-polymer construct was examined by histochemical method and scanning electron microscopy. Mesh type scaffold ($10 \times 10 \times0.4 mm$) was made of polyglycolic acid (PGA) suture thread. The PGA mesh type scaffold was 45% in porosity, and 0.03 g in weight. The primary cultured VSMCs were confirmed with immunohistochemical staining using monoclonal anti-$\alpha$-smooth muscle actin. The density and distribution of proliferated VSMCs within the scaffold and cellular adherence on the surface of the scaffold showed better results in the static seeding condition than in the dynamic condition. Under the same condition of seeding method as the static condition, the dynamic culture condition showed enhanced proliferation rates of the VSMCs when compared to the static culture condition. In conclusion, to improve the VSMCs proliferation in vitro, static seeding is better than the dynamic condition. In the culture condition, however, culture under the dynamic status is better than the static condition. This was a pilot study to manufacture artificial vascular vessel by tissue engineering.

• 한국작물학회지
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• 제54권4호
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• pp.407-415
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• 2009

본 연구는 2007년 국립식량과학원 시험포장에서 찰옥수수의 조생종 품종 찰옥 1호와 만생종 품종 찰옥 4호를 재료로 하여, 적정육묘 일수, 충실한 묘를 육성하기 위한 플러그셀 크기에 대한 일련의 실험을 수행한 것으로 그 결과를 요약하면 다음과 같았다. 1. 찰옥수수 묘의 묘장, 엽수 및 건물중은 파종기와 플러그셀 크기에 따라서 고도로 유의한 차이가 있었으나, 품종간에는 차이가 없었는데. 찰옥수수의 묘는 3월 파종 보다 5월과 7월 파종에서 생장속도가 빨랐다. 2. 찰옥수수 묘의 묘장과 엽수는 육묘일수가 길수록 증가하였는데, 3월 14일 파종에서는 30일 묘(21.6 cm), 5월 8일 파종에서는 15일 묘(25.5~26.9 cm), 그리고 7월 3일 파종에서는 10일 묘(21.6~24.0 cm)에서 이식에 적합한 묘장이 되었으며, 엽수는 3월 14일 파종에서는 파종 후 15~20일, 그리고 5월 8일과 7월 3일 파종에서는 파종 후 10일에 이식에 적합한 2~3매가 되었다. 3. 건물중도 육묘일수가 길어질수록 증가하였는데, 3월 14일 파종에서는 육묘 30일에 0.43g, 5월 8일 파종은 20일에 0.57~0.67g, 7월 3일 파종은 15일에 0.53g이었고, 또한 육묘일수가 길어질수록 건물중 증가속도가 2~3배 빨라졌다. 4. 묘장과 엽수로 보아 찰옥수수의 적정육묘일수는 모든 플러그셀 크기에서 3월14일 파종에서는 20일, 그리고 5월과 7월 파종에서는 10~15일이었다. 5. 찰옥수수 플러그묘의 묘장, 엽수, 엽면적 및 건물중 간에는 높은 정의 상관이 있었으나, 엽색도는 대부분의 형질과 부의 상관을 보였다.

• 대한의용생체공학회:의공학회지
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• 제16권1호
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• pp.1-8
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• 1995

A variety of experiments of endothelial cell seeding onto artificial vessels have been performed. To improve endothelialization, one or two components of the extracellular matrix (ECM) have been used as an underlying matrix. In this study, the whole ECM excreted from fibroblasts was used as an underlying matrix. Fetal human fibroblasts were cultured on a polyurethane (PU) sheet. After a conflu; ence was attained, the cytoskeleton and the nuclei of the fibroblast were destroyed using Triton-X. Mitomycin, or irradiation. Omental microvascular endothelial cells from adult human were seeded onto various substrates. After 12 days in culture, the cells were counted. It was observed that the ECM treated by irradiation had the highest cell number. In addition, the cells on this substrate exhibited the most typical endothelial cell morphology. For preliminary animal experiments the PU vessels (inner diameter, 1.5mm) coated with ECM were implanted in the infrarena] abdominal aorta of rat. After the vessels had been implanted for 5 weeks, it was found that the surface of the PU vessels was completely covered with endothelia] cells. In conclusion, we can state that the fibroblast-derived whole ECM makes a better underlying substrate for the endothelialization of small diameter artificial vessels.

• 대한의용생체공학회:의공학회지
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• 제11권1호
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• pp.131-140
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• 1990

To improve antithrombogenicity of polymer that used in vascular graft and artificial organs, seeding of human endothelial cells on the polyurethane was studied. Human endothelial cells were ismlated from human umbilical veins, using type I collagenase, and identified with goat anti vWF antibodies. Human endothilial cell seeding was tried upon the polyurethane which has good mechanical property and resists stresses. The hydrophobic polyurethane surface was changed hydrophilic by corona discharf:e treatment. Surface hydrophilicity was measured with Wilhemly plate method and the goniometer. To evaluate matrix protein adsorption, fibronectin adsorption test was done. To eveluate cell adhesion, human endothelial cell attachment forces were measured rising a perfusion chamber of , ism diamter. Less cells were detached from the hydrophilically treated polyurethane. This showed that corona discharge on the polyurethane could improve matrix adsorption and endothelial cell attachment.

• 한국자원식물학회지
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• 제35권1호
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• pp.29-35
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• 2022

변산향유는 꿀풀과의 국내 자생식물로 식물분류학회지에 처음으로 알려졌다. 초장은 20-35 cm로 작고 잎은 혁질로 윤택이 있다. 꽃은 11월에 보라색으로 개화하는 특징을 갖고 있어 분화 및 지피용 관상소재로 활용도가 매우 높다. 따라서 본 연구는 관상식물로 활용하기 위해 변산향유의 육묘 시 플러그 트레이 종류(128, 162, 200구), 토양조성(원예상토: 마사 1:1, 2:1, 4:1), 파종 립수(1, 2, 3립) 및 추비 농도(0, 250, 500, 1000 mg/L)의 수준을 구명하기 위해 수행하였다. 연구의 결과 변산향유는 트레이의 셀 크기가 커질수록 생육도 비례하여 증가하였다. 토양조성에 따른 생육은 마사토의 비율이 증가할수록 생육이 억제되었다. 셀 당 파종량에 따른 생육은 파종량이 많아질수록 초장, 초폭, 엽장, 엽폭이 감소하였으나 개체당 엽수, 줄기직경, 근장은 큰 차이가 없었다. 추비농도별 처리는 농도가 높아질수록 생육도 증가하는 경향을 보였다. 따라서 변산향유는 육묘시 128구 트레이에 원예상토를 충진한 다음 셀 당 1립 파종하여 재배하며, 추비는 비교적 고농도인 1000 mg/L로 엽면살포하여 육묘하는 것이 가장 효과적일 것으로 판단된다.