• 전자공학회논문지D
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• 제36D권10호
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• pp.1-8
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• 1999

본 논문은 두께가 각각 다른 습식 산호막의 정전류 스트레스에 따른 SILC를 측정하여 SILC의 전도 mechanism 및 발생원인을 조사하였다. $N_2O$ 어닐링한 산화막의 SILC 특성도 조사하였다. 또한, 60A 두께의 $N_2O$ 어닐링한 터널링 산호막을 갖는 ,flash memory cell을 $0.25{\mu}m$ 설계규칙에 따라 제작하여 그 특성을 측정하였다. 그 결과, SILC의 발생 원인은 전기적 스트레스 인가에 따른 산호막내에 생성된 트랩 때문이며, SILC의 전도 mechanism은 전기장 세기가 8MV/cm 이하일 때 산호막 트랩을 경유한 modified F-N 터널링이 8MV/cm 이상일 때 전형적인 F-N터널링이 주도적임을 알 수 있었다. 60A의 $N_2O$ 어닐링한 산화막은 SILC에 대한 내성 측면에서 큰 개선 효과가 있음을 알 수 있었다. 또한 이 막을 flash memory cell의 터널링 산호막으로 이용할 경우, $10^6$회의 endurance와 10년 이상의 드레인 disturb가 보장되고 8V-프로그래밍이 가능한 특성을 얻을 수 있었다.

• 대한수의학회지
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• 제32권2호
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• pp.157-164
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• 1992

Changes in the both inward current and conductance of membrane by the fertilization were observed using the one microelectrode voltage clamp(or switch clamp) technique. Unfertilized eggs and both 1- and 2-cell stage eggs after fertilization were donated from the superovulated mouse (ICR, more than 6 weeks old) treated with PMSG(pregnant mare serum gonadotropin, Sigma) and HCG(human chorionic gonadotropin, Sigma) and naturally mated ones, respectively in this experiment. Membrane potential was held at -90mV and the voltage step was applied from -80mV to 50mV with interval of 10mV or 20mV for 300ms. since both of amplitudes and time courses in the membrane currents were various according to the states of cells and clamping condition, results were presented by their $averages{\pm}SEM$(standard mean error)and ratios or percentages. Inward currents began to appear in response to the step depolarization from -60mV and reached its maximum at -50mV. However, since the potential was not clamped evenly during the voltage step, current-voltage(I-V) relationship might be positively shifted 10 or 20mV. From the steady-state currents plotted in the I-V curve, outward rectification was markedly observed. Peak inward currents$(i_{in})$ at -50mV were $-0.62{\pm}0.23nA$(n=4),$-0.52{\pm}0.25nA$(n=5) and $-0.37{\pm}0.25nA$(n=6), in the 1-cell stage, 2-cell stage fertilized eggs and in the unfertilized eggs, respectively. Pure inward current (difference between steady-state and peak, $i_{in. pure}$) were $-1.01{\pm}0.23nA$, $-0.69{\pm}0.43nA$ and $-0.68{\pm}0.29nA$, respectively in the 1-cell stage fertilized eggs, unfertilized eggs and 2-cell stage fertilized eggs. These results suggested that the outward current in fertilized eggs of 2-cell stage was more increased than those in the unfertilized eggs. Pure inward currents in the all stages of eggs showed a similar fashion in the I-V relationship from -50mV to 50mV and reversal potential at 50mV. Time constant of inactivation$({\tau})$ in the inward current was decreased as the membrane potential was depolarized in the unfertilized and 2-cell stage eggs but in the 1-cell stage eggs t was not likely to be affected significantly. Slope conductances were 14.2nS, 8.9n5 and 7.7nS in the 1-cell, 2-cell stage fertilized eggs and the unfertilized eggs, respectively. Membranes between two cells within a zona pellucida seem to be electrical-connected in the 2-cell stage eggs from the observation made in the analysis for the electronic spread and decay to the current stimuli. Both of inward current and membrane conductance were increased after fertilization in the mouse eggs. Inward current seems to be carried by the same ion or through the same channels up to the 2-cell stage and ion that carried inward current was thought to play important function after fertilization in the mouse eggs.

• 대한한의학회지
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• 제26권4호
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• pp.12-21
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• 2005

Objectives: In the present study, we investigated whether an aqueous extract of Armeniacae semen induces apoptotic neuronal cell death upon mouse N2a neuroblastoma cells. Methods: 1. Cell viability was determined by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTI) assay. 2. For in situ detection of apoptotic cells, terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay, 4,6-diamidino-2-phenylindole (DAPI) staining. 3. The fraction of cells was revealed by flow cytometric analysis used that. 4. For detection of apoptotic DNA cleavage, DNA fragmentation assay was performed. 5. For detection of bax and bcl-2, Western blot analysis was performed. 6. Caspase enzyme activity was measured using caspase-3 assay. Results: From the present results, N2a neuroblastoma cells treated with Armeniacae semen extract exhibited several characteristics of apoptosis. A treatment of Armeniacae semen extract was shown to increase the expression of Bax, a proapoptotic protein, and the treatment decreased the expression of Blc2, an anti-apoptotic protein. In addition, Armeniacae semen extract increased the caspase-3 enzyme activity. Conclusions: The present results show that Armeniacae semen extract induces apoptotic cell death in mouse N2a neuroblastoma cells.

• The Korean Journal of Ecology
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• 제20권3호
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• pp.169-173
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• 1997

The measurement of cell death constant in Anabaena flos-aquae was tested by the Live/Dead BacLight Viability kit(Molecular Probes Co., Seatle, WA). When the Live/Dead BacLight Viability kit was applied to Anabaena flos-aquae, the cells with intact cell membranes(live cells) stained fluorescent green, while the cell with damaged membranes(dead cells) stained fluorescent red and the background remained virtually nonfluorescent. The rations of live : dead cells in the cell suspension were controlled artifically and Live/Dead BacLight Viability kit was applied to them. The ratios of green:red fluorescent cells in the cell suspension were the same as those of live : dead cells controlled artifically. It was also approved by the fluorescence emission. The cell death constant was measured in the P-limited Anabaena flos-aquae chemostal culture in the N-fixing and $KNO_3-supplied$ conditions. The culture in N-fixing chemostat had a dead cell proportion of 1.2% at the growth rate of 0.7/day and increased to 2.6% at the growth rate of 0.3/day. The cell death constant of N-fixing culture was 0.008/day.There was a same trend in the $KNO_3-supplied$ chemostat culture. The proportion of dead cell was 1.6% of dead cell proportion at the growth rate of 0.7/day and increased to 4.3% at the growth rate of 0.3/day.

• Tuberculosis and Respiratory Diseases
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• 제41권6호
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• pp.616-623
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• 1994

연구목적: 수술전 전산화 단층촬영상 임파절종대의 소견이 없는 $T_{1-3}N_0M_0$비소세포폐암 환자들을 대상으로 수술전 후 병기의 차이를 비교하여 이들에 있어 수술전 관혈적인 병기판정의 필요성에 대하여 검토하였다. 방법: 경북대학교병원에서 비소세포폐암으로 개흉절제술을 받았던 환자들 가운데 수술전 병기가 $T_{1-3}N_0M_0$인 41명을 대상으로 수술전과 수술후의 병기의 차이를 비교하였다. 결과: 1) 수술전 병기는 I기의 경우 $T_1N_0M_0$ 3예, $T_2N_0M_0$ 32예로 모두 35예였고 IIIa기 ($T_3N_0M_0$)는 6예였다. 종양의 위치는 중심형 폐암 24예, 말초형 폐암 17예였는데 IIIa기는 모두 중심형 폐암이었다. 2) 수술후 병기는 I기의 경우 $T_1N_0M_0$ 2예, $T_2N_0M_0$ 25예로 모두 27예였고 II기의 경우 $T_1N_1M_0$ 1예, $T_2N_1M_0$ 3예로 모두 4예였으며 IIIa기는 $T_3N_0M_0$ 1예, $T_3N_1M_0$ 2예, $T_3N_2M_0$ 4예, $T_2N_2M_0$ 2예로 모두 9예였고 IIIb기($T_4N_1M_0$)는 1예였다. 3) 수술후 T의 변화가 있은 경우는 $T_2$ 32예 가운데 2예는 $T_3$로 $T_3$ 6예중 1예는 $T_4$로 판명되었다. 4) 수술후 $N_1$으로 판명된 경우는 7예였고 $N_2$로 판명된 경우는 6예였다. 5) 수술전 T에 따른 임파절전이는 $T_{1-2}$인 경우는 35예 중 8예($N_1$ 5예, $N_2$ 3예)였고 $T_3$인 경우는 6예중 5예($N_1$ 2예, $N_2$ 3예)로 $T_{1-2}$에 비해 $T_3$에서 임파절 전이빈도가 높았고 $N_2/N_1$비도 높았다 그러나 수술전 $T_{1-2}$경우 종양의 위치에 따른 임파절전이의 차이는 없었다. 6) 41예의 대상환자중 $N_2$ 6예와 $T_4$ 1예를 제외한 34예에서 완전 절제가 가능하였다. 결론: 이상의 결과로 전산화 단층촬영상 임파절종대가 없는 비소세포암의 수술전 병기판정시 수술전 $T_3$에서는 종격동경 검사 등의 관혈적인 병기판정방법이 필요하리라 생각된다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1990년도 추계학술대회 논문집
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• pp.88-90
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• 1990

In this study, PN junction solar cell and P$\^$+/-N-N$\^$+/ BSF solar cell, using N-type(111), 10$\^$16/[atoms/cm$\^$-3/] wafer, were fabricated applying that ion implant method whose dose are 1E14, 1E15, 3E15 and its acceleration energy is 50Key, 100Key respectively. The impurity concentration of two types of front-side are 10$\^$18/[atoms/cm$\^$-3/] and back-side concentration for BSF solar cell is 10$\^$17/[atoms/cm$\^$-3/]. As a result of comparison for 2 typical types of cells out of various fabricated samples, open circuit voltage (Voc), short circuit current(Isc) of BSF solar cell are larger than those of PN solar cell by 48[%], 14[%]. Considering that the efficiency of BSF cell is 2.5[%] as well as PN solar cell's is 7.5[%], 10.0[%] of efficiency improvement effect can be obtained from BSF solar cell. Futhermore, in consequence of front-side impurity concentration change from 10$\^$17/[atoms/cm$\^$-3] to 10$\^$20/[atoms/cm$\^$-3/] alternately, the most ideal result can be expected when it is 10$\^$18/[atoms/cm$\^$-3/].

• Journal of Korean Neurosurgical Society
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• 제49권1호
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• pp.13-19
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• 2011

Objective: The purpose of this study is to investigate the combined effects of ginkgo biloba extract, ginkgolide A and B and aspirin on SK-N-MC, human neuroblastoma cell viability and mRNA expression of growth associated protein43 (GAP43), Microtubule-associated protein 2 (MAP2), B-cell lymphoma2 (Bcl2) and protein53 (p53) gene in hypoxia and reperfusion condition. Methods: SK-N-MC cells were cultured with Dulbecco's Modified Eagle's Medium (DMEM) media in $37^{\circ}C$, 5% $CO_2$ incubator. The cells were cultured for 8 hours in non-glucose media and hypoxic condition and for 12 hours in normal media and $O_2$ concentration. Cell survival rate was measured with Cell Counting Kit-8 (CCK-8) reagent assay. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to estimate mRNA levels of GAP43, MAP2, Bcl2, and p53 genes. Results: The ginkgolide A and B increased viable cell number decreased in hypoxic and reperfused condition. The co-treatment of ginkgolide B with aspirin also increased the number of viable cells, however, there was no additive effect. Although there was no increase of mRNA expression of GAP43, MAP2, and Bcl2 in SK-N-MC cells with individual treatment of ginkgolide A, B or aspirin in hypoxic and reperfused condition, the co-treatment of ginkgolide A or B with aspirin significantly increased GAP43 and Bcl2 mRNA levels. In MAP2, only the co-treatment of ginkgolide A and aspirin showed increasing effect. The mRNA expression of p53 had no change in all treating conditions. Conclusion: This study suggests that the combined treatments of Ginkgo biloba extracts and aspirin increase the regeneration of neuroblastoma cells injured by hypoxia and reperfusion.

• 한국구조물진단유지관리공학회 논문집
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• 제20권2호
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• pp.60-66
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• 2016

본 연구는 실리콘계 정포제의 특성에 따른 폴리우레탄 폼 지수제의 cell 구조와 흡수량 변화를 알아보기 위하여 6종의 정포제를 사용하여 폴리우레탄 폼 지수제를 제조하여 FE-SEM으로 분석한 결과 실리콘 정포제의 실록산 주사슬 말단에 PO n개가 결합되어 있는 DC-193, DC-2585, DC-5125, DC-198의 cell 구조는 close cell로 확인이 되었고, 실리콘 정포제의 실록산 주사슬 말단에 EO n개가 결합 되어 있는 DC-5043과 DC-5598은 open cell 구조로 나타났다. 또한 cell 구조 변화에 따른 흡수량 에서는 close cell의 크기가 가장 세밀하고 균일한 DC-193의 흡수량이 가장 적게 나타나 내수성이 가장 우수한 것으로 나타났으며 open cell의 크기가 가장 크게 형성된 DC-5043의 흡수량이 가장 많은 것으로 나타났다. 이들의 방수성능을 콘크리트 구조물을 모사하여 시험한 결과 누수가 없음을 확인하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.204-205
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• 2011

In thin film silicon solar cells, p-i-n structure is adopted instead of p/n junction structure as in wafer-based Si solar cells. PECVD is a most widely used thin film deposition process for a-Si:H or ${\mu}c$-Si:H solar cells. For best performance of thin film silicon solar cell, the dopant profiles at p/i and i/n interfaces need to be as sharp as possible. The sharpness of dopant profiles can easily achieved when using multi-chamber PECVD equipment, in which each layer is deposited in separate chamber. However, in a single-chamber PECVD system, doped and intrinsic layers are deposited in one plasma chamber, which inevitably impedes sharp dopant profiles at the interfaces due to the contamination from previous deposition process. The cross-contamination between layers is a serious drawback of a single-chamber PECVD system in spite of the advantage of lower initial investment cost for the equipment. In order to resolve the cross-contamination problem in single-chamber PECVD systems, flushing method of the chamber with NH3 gas or water vapor after doped layer deposition process has been used. In this study, a new plasma process to solve the cross-contamination problem in a single-chamber PECVD system was suggested. A single-chamber VHF-PECVD system was used for superstrate type p-i-n a-Si:H solar cell manufacturing on Asahi-type U FTO glass. A 80 MHz and 20 watts of pulsed RF power was applied to the parallel plate RF cathode at the frequency of 10 kHz and 80% duty ratio. A mixture gas of Ar, H2 and SiH4 was used for i-layer deposition and the deposition pressure was 0.4 Torr. For p and n layer deposition, B2H6 and PH3 was used as doping gas, respectively. The deposition temperature was $250^{\circ}C$ and the total p-i-n layer thickness was about $3500{\AA}$. In order to remove the deposited B inside of the vacuum chamber during p-layer deposition, a high pulsed RF power of about 80 W was applied right after p-layer deposition without SiH4 gas, which is followed by i-layer and n-layer deposition. Finally, Ag was deposited as top electrode. The best initial solar cell efficiency of 9.5 % for test cell area of 0.2 $cm^2$ could be achieved by applying the in-situ plasma cleaning method. The dependence on RF power and treatment time was investigated along with the SIMS analysis of the p-i interface for boron profiles.

• KSBB Journal
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• 제15권1호
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• pp.27-34
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• 2000

남해안 유류 오염지역으로부터 유류분해능이 우수한 균주를 선별하여 동정한 결과 Pseudomonas aeruginosa로 동정되었으며, Pseudomonas aeruginosa BYK-2로 명명하였다. 균 성장 및 생물 유화제 생산을 위한 최적배양온도, 시간, pH, NaCl 농도는 각각 $25^{\circ}C$, 48시간, 7.0 이었으며, NaCl은 첨가하지 않았을 때 가장 많은 양의 생물유화체가 생산되었다. 본 균주의 경우, 1%(w/v) arabian light 원유와 bunker C oil을 기질로 7일간 배양한 결과 92.1%(w/w)와 76.2%(w/w)가 생분해되었다. n-hexadccane 에 대한 세포부착능이 실험에서는 탄화수소화합물들(arabian light 원유, kuwait 원유, bunker C 유, n-paraffine, n-hexadecane, n-tetradecane)을 기질로 배양했을때는 모두 80% 이상의 높은 세포부착능을 나타냈으며, 지방산들(oleic acid, olive oil, lecithin)중에는 lecithin을 기질로 배양했을 때 91.5%로 가장 높은 세포부착능을 나타냈어다. 또한 당들(arabinose, trehalose, dextrose, galactose, lactose, fructose, maltose, sorbitol, sucrose)을 기질로 했을 경우 arabinose, galactose, sorbitol, sucrose를 제외하고는 대부분 70%이하의 세포부착능을 나타냈다.