• Title/Summary/Keyword: Science park 3.0

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Study on the Properties of $CuInSe_2$ absorber layer from Selenization using a closed Vacuum Quartz box (진공 석영관에서 Selenization한 $CuInSe_2$ 광흡수층 특성 연 구)

  • Yang, Hyeon-Hyn;Back, Su-Ung;Kim, Han-Wool;Han, Chang-Jun;Na, Kil-Ju;Lee, Suk-Ho;So, Soon-Youl;Park, Gye-Choon;Lee, Jin;Chung, Hae-Deok
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2010.06a
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    • pp.229-229
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    • 2010
  • 본 실험에서는 $CuInSe_2$, 3원물질을 화학량론적 조성비가 되도록 박막을 제조하기 위해 각 단위원소를 원자비에 맞춰 전자선가열 진공증착기를 사용하여 Cu, In, Se 순으로 증착하였다. $10^{-3}$torr 이상의 진공석영관에서 열처리와 동시에 Selenization을 통해 제작된 $CuInSe_2$박막은 열처리온도 $250^{\circ}C$에서는 $Cu_xSe$, CuSe등의 2차상들이 나타나다가 $450^{\circ}C$이상의 고온에서 $CuInSe_2$ 단일상을 형성하였다. 이로부터 진공중에서 반응을 시켰을 때, 더 낮은 온도에서 반응이 일어나고 열역학적으로 보다 안정한 소수의 화합물들이 쉽게 형성됨을 확인할 수 있었다. 특히 $250^{\circ}C$에서는 Sphalerite 구조를 가지다가 $350^{\circ}C$이상의 온도에서 Selenization하였을 때 Chalcopyrite 구조를 가졌다. 박막이 두꺼워지면서 결정립의 크기가 커지고 응력이 작아지는 특성을 보였다. 에너지 밴드갭은($E_g$)은 Cu/In 성분비율이 클수록 작은값을 보였으며, 결절립크기가 증대되므로 결국 흡수계수가 낮아짐을 알 수 있다. 또한 두께가 증가할수록 전반적으로 흡수계수가 증가하였고 Cu/In의 성분비율이 0.97일 때 기초흡수파장은 1,169nm이고 에너지밴드갭은 1.06eV이었으며, 두께 $1.5{\mu}m$이상일 때 전반적으로 양호한 상태의 p-type $CuInSe_2$ 박막을 제작 하였다.

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A photoelastic Stress Analysis of Implant Prosthesis According to Fitness of Super structure (불량 적합 임플란트 보철물의 광탄성 응력 분석)

  • Lim, Hyun-Pil;Heo, Shin-Ok;Kim, Hong-Joo;Park, Sang-Won
    • Journal of Dental Rehabilitation and Applied Science
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    • v.26 no.1
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    • pp.39-46
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    • 2010
  • To assess the stress distribution of implant prosthesis induced by intentional misfit using photoelastic model. Stress was measured at the surrounding bone after applying vertical load to the implant. Three implants were placed in each of three photoelastic resin blocks. No misfits were used for the control group, while for the experimental group $100{\mu}m$ misfit after cutting the crown was used. The photoelastic stress analysis was performed. In control group, stress concentration was not shown when the load was not applied, whereas stress concentration was shown only in the loaded part even when load was applied and the stress was distributed in anterior-posterior direction when applying a load in the middle. When intentional misfits were given, stress around the fixture was incurred when tightening the screw even if load was not applied. If the load was applied, stress was concentrated around the implants including areas where the load was applied. In particular, the prosthesis made of UCLA showed more stress concentration as compared with a conical abutment. In the UCLA case, concentration was shown from the apex following through the axis to the cervical area. Prosthesis with misfit makes the stress concentrated though the load was not applied and it induces even more severe stress concentration when the load was applied. This founding demonstrates the importance of the correct prosthesis production.

Comparison of the Proliferation pattern of Cultured Rat Calvaria Cell on the Resorbable Barrier Membrane (흡수성 차폐막에 배양된 구개관세포의 증식양상의 비교)

  • Lee, Chang-Hoon;Lee, Man-Sup;Kwon, Young-Hyuk;Park, Joon-Bong;Herr, Yeek
    • Journal of Periodontal and Implant Science
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    • v.33 no.2
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    • pp.193-213
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    • 2003
  • The purpose of this study is to evaluate the phenomenon of attachment and spreading of the cultured rat calvarial cell inoculated on their surface of different kinds of biodegradable membrane which had been used on tissue regeneration on periodontal defects by using scanning electron microscope. In this experiment 30 Sprague-Dawley male rats (mean BW 150gm) were used to harvest abundant number of cell in the short period. The rats were sacrificed by decapitatioan to obtain the calvaria for bone cell culture. Calvarial cells were cultured with Dulbecco's Modified Essential Medium contained with 10% Fetal Bovine Serum under the conventional conditions. Biodegradable barrier membrane were collected with collagen type, and were divided into 3 different kind of surface such as scattered, polarized and fine-net type as their surface texture. Microcover plate which usually used for cell culture was used as control for smooth surface. All the membrane were seeded with cultured calvarial cell on their surface. The number of cell inoculated on the membrane were $1{\times}10^6$ Cells/ml. After the culture as designed time, all the membrane were washed with 0.1 M Phosphate Buffered saline and fuxed with 2.5% Glutaraldehyde. And all specimen were treated with $OsO_4$, and Tannic acid before drying the cell for coating the cell with gold. Scanning Electron Microscope was used to observation. The following results were obtained. I. During the whole period of experiment, the phenomenon of cell attachment and spreading were revealed similar pattern to compare with smooth surface culture plate and ordinary culture dish. 2. The shape of cell attachment and spreading on the surface of barrier membrane were observed no remarked difference pattern between smooth surface culture plate and ordinary culture dish. 3. The cytoplasmic process of cultured calvaria cell extent to the deep portion of barrier membrane like as their own proper shape. 4. There were no remarkable relationships between the degree of cultured cell spreading and surface structure of barrier membrane. 5. Slight starified layer of cultured calvaria cell were observed on the scattered type of resorbable membrane, Conclusively, this study thus suggest that cultured bone cell inoculated onto the biodegradable barrier membrane may have an important role of carrier for many cell which could be used as new tissue regeneration, and those tissue engeering technique may become an new method in the approach to the repair of bone defects.

Anti-inflammatory and Anti-allergic Effect of Extractsfrom Organic Soybean (유기농 콩 추출물의 항염증 및 항알레르기 효과)

  • Chung, Eun-Kyung;Seo, Eun-Hye;Park, Jun-Ho;Shim, Hye-Rim;Kim, Kyung-Hee;Lee, Byung-Ryong
    • Korean Journal of Organic Agriculture
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    • v.19 no.2
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    • pp.245-253
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    • 2011
  • This study was carried out to investigate the biological effects of organic soybean extracts. Cellular and molecular analysis was performed to determine anti-oxidative, anti-inflammatory, anti-apoptotic, and anti-inflammatory effects of soybean extracts. First, we obtained various solvent extracts of soybean such as water, ethanol, and methanol. Molecular and cellular analysis were performed with 0.1 mg/ml concentration of each solvent extracts. The results of anti-oxidative, antiinflammatory and anti-apoptotic effects of organic soybean extracts were prominent. However, organic soybean extracts were not observed in anti-allergic effects determined by releasing histamine from rat mast cell line, RBL-2H3. Conclusively, organic soybean suppress inflammatory responses. In addition, organic soybean could be applied as a functional food ingredient for treatment of chronic inflammation, asthma, and atopic dermatitis with enhanced anti-inflammatory activities.

Molecular Gene Cloning, Expression, and Characterization of Bovine Brain Glutamate Dehydrogenase

  • Kim, Dae-Won;Eum, Won-Sik;Jang, Sang-Ho;Yoon, Chang-Sik;Kim, Young-Hoon;Choi, Soo-Hyun;Choi, Hee-Soon;Kim, So-Young;Kwon, Hyeok-Yil;Kang, Jung-Hoon;Kwon, Oh-Shin;Cho, Sung-Woo;Park, Jin-Seu;Choi, Soo-Young
    • BMB Reports
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    • v.36 no.6
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    • pp.545-551
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    • 2003
  • A cDNA of bovine brain glutamate dehydrogenase (GDH) was isolated from a cDNA library by recombinant PCR. The isolated cDNA has an open-reading frame of 1677 nucleotides, which codes for 559 amino acids. The expression of the recombinant bovine brain GDH enzyme was achieved in E. coli. BL21 (DE3) by using the pET-15b expression vector containing a T7 promoter. The recombinant GDH protein was also purified and characterized. The amino acid sequence was found 90% homologous to the human GDH. The molecular mass of the expressed GDH enzyme was estimated as 50 kDa by SDS-PAGE and Western blot using monoclonal antibodies against bovine brain GDH. The kinetic parameters of the expressed recombinant GDH enzymes were quite similar to those of the purified bovine brain GDH. The $K_m$ and $V_{max}$ values for $NAD^+$ were 0.1 mM and $1.08\;{\mu}mol/min/mg$, respectively. The catalytic activities of the recombinant GDH enzymes were inhibited by ATP in a concentration-dependent manner over the range of 10 - $100\;{\mu}M$, whereas, ADP increased the enzyme activity up to 2.3-fold. These results indicate that the recombinant-expressed bovine brain GDH that is produced has biochemical properties that are very similar to those of the purified GDH enzyme.

Production and utilization of organic compost from spent mushroom (Pleurotus eryngii) substrate (큰느타리버섯 수확 후 배지를 이용한 유기퇴비 제조 및 활용)

  • Lee, Sang-Hwa;Park, Ju-Ri;Oh, So-Ra;Ryu, Song-Yi;Ryu, Young-Hyun;Kang, Min-Gu;Lee, Suk-Hee;Jo, Woo-Sik
    • Journal of Mushroom
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    • v.16 no.1
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    • pp.39-44
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    • 2018
  • We investigated the possibility of utilizing spent mushroom culture-medium as raw material to produce organic compost. Mushroom culture-medium contained 2.69% nitrogen, 41.07% carbon, and 0.99% phosphoric acid. Nitrogen and carbon content in rice bran were 3.08% and 47.34%, respectively. Nitrogen, carbon, and phosphoric acid content in mushroom Pleurotus eryngii were 3.41%, 34.63%, and 1.70%, respectively. Our study aimed to evaluate the degree of decay of compost produced from the substrate, used to culture King Oyster mushrooms by analyzing seed germination indexes in cucumber, radish, lettuce, and Chinese cabbage. Our results showed that compost from spent mushroom culture-medium completed the stabilization process in 4 to 6 weeks, as evaluated by the appropriate organic compost maturity point for the plantation.

Protective effect of ethanolic extract of antler-shaped Ganoderma lingzhi against oxidative stress in PC12 neuronal cell line (PC12 신경세포주에서 녹각영지버섯 주정 추출물의 산화 스트레스 개선 효과)

  • Kim, Hyung Don;Lee, Eun Young;Park, Jeong-Yong;Seo, Kyung Hye;Lee, Kang-Hyo;Choi, Jehun;Han, Jae-Gu;Cho, Jae-Han;Lee, Seung Eun
    • Journal of Mushroom
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    • v.16 no.3
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    • pp.213-217
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    • 2018
  • This study was carried out to identify medicinal mushrooms with protective effects against oxidative stress in PC12 neuronal cell line, followed by evaluation of their antioxidant property. Extracts of medicinal mushrooms, including Ganoderma lucidum extract (GLE), antler-shaped Ganoderma lingzhi extract (AGLE), Hericium erinaceus extract (HEE), and Sanghuangporus baumii extract (SBE), were screened for cytotoxicity using MTT assay. None of the extracts up to $10{\mu}g/ml$ concentration affected cell viability. These extracts were further checked for their protective effect against oxidative stress-induced reactive oxygen species (ROS) production. Exposure to $50{\mu}M$ $H_2O_2$ induced ROS generation in PC12 cells, which was inhibited only by treatment with AGLE. In addition, inhibition of $H_2O_2-induced$ ROS generation by AGLE was found to be in a dose-dependent manner (2.5, 5, and $10{\mu}g/ml$). Microscopic examination of DCF fluorescence for detection of ROS showed a similar pattern. Further, antioxidant activity of AGLE was determined by ABTS radical cation assay, and its $IC_{50}$ was found to be $46.90{\pm}0.31{\mu}g/ml$. Taken together, these results suggest that AGLE may help to alleviate oxidative stress in PC12 neuronal cells.

Factors Influencing on Learning Flow of Nursing Students (간호대학생의 학습몰입에 영향을 미치는 요인)

  • Kim, Seon-Hwa;Park, Sang-Youn
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.3
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    • pp.1557-1565
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    • 2014
  • The purpose of this study was to identify the factors influencing learning flow of nursing student. Design of this study was a descriptive research. The participants for this study were 283 nursing college students with four-years curriculum in D city from June 14th to June 24th, 2013. Data were analyzed using descriptive statistics, t-test, one way ANOVA, Pearson's correlation and multiple regression with SPSS 18.0 Program. There were significant correlations among self-leadership, academic self-efficacy, major satisfaction, and the learning flow. As a multiple regression analysis, factors that have an effect on learning flow were self-leadership, and academic self-efficacy. These factors explain 58.2% of the variance in learning flow. Self-leadership, academic self-efficacy, and learning flow relationship were positive relevant. To enhance learning flow ability for nursing students, it is necessary to develop training program and academic environment for increasing self-leadership and academic self-efficacy.

Influence of Crown Gall Infection on Growth and Flowering of Rose (뿌리혹병 감염이 장미의 생육과 개화에 미치는 영향)

  • Han, Kyung-Sook;Kim, Won-Hee;Park, Jong-Han;Han, You-Kyoung;Cheong, Seung-Rong
    • Research in Plant Disease
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    • v.14 no.3
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    • pp.159-164
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    • 2008
  • Crown gall of rose (Rosa hybrida) was observed in greenhouse during 2003-2007. The average disease incidence was up to 38.1 % and was more severe in hydroponic culture as compared to soil culture. The typical gall symptom occurred mainly on the root, crown, or both, and resulted on poor rooting, growth retardation and yield loss. The reduction rate of rooting influenced by crown gall was 57.5% as compared to healthy plants on nursery stock. The location of gall formation in the plant influenced growth vigor resulting in symptoms such as poor shooting. Healthy plants produced 19.1 flowers/$m^2$, while diseased plants produced 9.5 flowers/$m^2$ during the same cultivation period. Moreover, the number of days to flowering was longer for the diseased plants than for healthy plants - 51.2 days and 39.8 days for first harvest, and 60.6 days and 52.1 days for the second harvest, respectively. Conclusively, infection on the basal stem caused serious loss of the number of shoot formation; yield loss of cut flower was 38.7% due to crown gall infection and delay of harvesting time about 8-10 days.

A study on the children's oral health behavior according to the general characteristics of parents (부모의 일반적인 특성에 따른 자녀의 구강보건 행태에 관한 연구)

  • Jang, Gye-Won;Park, Sung-Suk
    • Journal of Korean society of Dental Hygiene
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    • v.10 no.6
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    • pp.1049-1059
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    • 2010
  • Objective : The purpose of this study was to examine the relationship of the general characteristics of parents to their children's oral health care. The subjects in this study were 117 parents and their children who resided in rural communities in the region of K. Methods : A survey was conducted with the consent of the parents from July 1 to 30, 2010. As for the survey on the children, the children who were in the lower grades were interviewed, and the upper graders filled out the questionnaires in person. A frequency analysis was carried out to find out the general characteristics of the parents and children, and x2-test was utilized to grasp the links between the general characteristics of the parents and the children's oral health care. A SPSS WIN 12.0 program was employed to analyze all the collected data. The findings of the study were as follows: Result : 1. As a result of investigating the relationship of the occupation of the parents to the children's regular dental checkup, the 71.8 percent of the entire children didn't get a dental checkup on a regular basis. The biggest percentage of the children of the self-employed parents(100%) got a regular dental checkup, and 90.9 percent of the children of the government workers did that(p<.05). 2. As a result of checking the relationship of the occupation of the parents to the children's dental-caries experiences, 39.3 percent of the whole children had no such experiences. The largest percentage of the children of the company employees(51.9%) had dental-caries experiences(p<.05). 3. Concerning the links between the academic credential of the parents and the children's toothbrushing method, the biggest percentage of the children(40.2%) brushed their teeth up and down. The largest rate of the children whose parents were high-school graduates(41.5%) brushed their teeth in that way(p<.05). 4. Regarding the links between the toothbrushing time of the parents and the children's view, 43.6 percent found their parents to take good care of their teeth to make them clean. 60 percent whose parents brushed their teeth after having breakfast and dinner took the best view(p<.001). 5. As for the oral-health education experiences of the parents and a time for the children's change of toothbrushes, 29.1 percent changed their toothbrushes every two months, and 29.1 percent did that not on a regular basis but when the bristles of their toothbrushes got bent(p<.05). Conclusions : The above-mentioned findings suggest that in order to promote children's oral health in consideration of the characteristics of their parents, children should be urged to get a regular dental checkup, and the development of oral-health education programs in which parents and children can participate together is urgently required.