• 한국식물학회:학술대회논문집
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• 한국식물학회 1999년도 Proceedings of the 17th Symposium on Plant Biology Environmental Stress and Photosynthesis
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• pp.55-67
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• 1999

A puc -deleted cell of Rhodobacter sphaeroides grows with a doubling time longer than 160 h under the light-limiting photoheterotrophic ( 3 Watts [W]/㎡) conditions due to an absence of the peripheral light-harvesting B800-850 complex. A spontaneous fast-growing mutant, R.sphaeroides SK101 was ioslate dto have∼40-h doubling at 3 Watts/㎡, while the growth of the mutant was not distinguished from its parental strain during both aerobic and light-saturating photoheterotrphic (10W/㎡) growth. The B875 complex of SK101 under the light-limiting conditions was elevated by 20 to 30% compared with that of the puc -deleted cell, reflecting parallel increase of bacteriochlorophyll and carotenoid contents of the mutant. The formation of B875 complex of SK101 under the anaerobic dark conditions with dimethylsulfoxide was the same as that of the puc-deleted cell. suggesting that the mutation of SK101 result in the altered control of B875 complex formation by light. When puc is restored in SK101 , it is not B875 complex but B800-850 complex which formation is elevated. The mutation of SK101 affected the bchF transcription most drastically to show two to tenfold increase during both aerobic and photoheterotrophic growth. The mutated phenotype of SK101 was complemented with pW2, which contains approximately 100-kb HNA of the photosynthetic gene clusters. The complementing DNA was narrowed down to a 1.1-kb DNA containing orfQ and pufKBA . The mutation of SK101 appeared to be exerted through the mutation of the orfQ gene encoding a putative bacteriochlorophyll -mobilizing protein.

• Reproductive and Developmental Biology
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• 제28권1호
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• pp.7-12
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• 2004

This study was performed to establish the effective culture condition for the establishment of clonal lines from porcine fetal fibroblast cells. Fibroblasts derived from a pig fetus (Day 50) were cultured and passaged two times before use. A single cell was seeded in 96-well plates, cultured in medium supplemented with different concentrations of FBS, catalase or $\beta$-mercaptoethanol ($\beta$ME), and classified by cell size and morphology. Cells were passaged two times into 4-well dish before freezing. The establishment efficiencies were not different among different concentrations of FBS (0.3 to 5.1%). However, population doubling time (PDT) was significantly decreased by increasing the FBS concentration (P＜0.05). The establishment efficiency of $\beta$ME-added group (10.4%) was significantly higher than those of catalase-added and control groups (3.5%, and 3.5%, respectively, p＜0.05), and PDT was significantly decreased (23.6 vs 28.1, and 25.5 h, respectively, p＜0.05). However, catalase did not show a positive effect on the establishment efficiency. Cell size and morphology did not affect the establishment efficiency and PDT of clonal lines. The result of present study shows that the establishment efficiency of clonal cell lines can be enhanced by the culture in media supplemented with 30% FBS and $\beta$ME.

• 한국응용곤충학회지
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• 제47권4호
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• pp.365-368
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• 2008

싸리수염진딧물(Aulacorthum solani Kaltenbach)의 성충 수명과 산자수를 $12.5{\sim}25^{\circ}C$, 상대습도 $60{\sim}70%$, 광주기 16L:8D 조건에서 조사하여 생명표를 작성하였다. 싸리수염진딧물 성충은 $12.5{\sim}25^{\circ}C$에서의 수명이 $34.3{\sim}10.5$일로 온도의 상승에 따라 성충기간이 짧아졌다. 산자수는 $15^{\circ}C$에서 74.1마리로 최고치를 보였으며, $15{\sim}25^{\circ}C$에서는 온도가 상승함에 따라 산자수가 감소하였으나, $12.5^{\circ}C$에서는 47.0마리로 온도가 낮아짐에 따라 산자수가 적어지는 경향을 보였다. 또한 싸리수염진딧물 성충의 일일 산자수는 $20^{\circ}C$에서 2.9마리였고, $12.5^{\circ}C$에서 1.4마리와 $30^{\circ}C$에서 1.3마리로 온도가 높거나 낮아지면 일일산자수가 적어졌다. 싸리수염진딧물 약충 발육시 사망률과 성충 수명, 산자수를 이용하여 생명표를 작성하였는데 싸리수염진딧물은 순증가율(Ro)이 $15^{\circ}C$에서 58.7, 내적자연증가율($r_m$)은 $20^{\circ}C$에서 0.27, 기간증가율(${\lambda}$)은 $20^{\circ}C$에서 1.32이었으며, 배수기간(Dt)은 $20^{\circ}C$에서 2.52, 세대기간(T)은 $22.5^{\circ}C$에서 10.99로 가장 짧았다.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.316.3-317
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• 2002

In previous reports, we exhibited that acteoside showed significant cytotoxicity against various cancer cells. In this study we investigated that acteoside is capable of inducing differentiation in HL -60 human leukemia cell line. After being treated with acteoside, the growth curve was decreased remakably in a dose- and time-dependent manner, and cell doubling time was delayed. Exposure of cells to 20 $\mu\textrm{g}$/m$\ell$ acteoside induced differentiation of HL-60 cells to monocyte/macrophage-like cells by cell surface antigen expression. The percentage of NBT reducing activity was increased in a time-dependent manner. In addition. the protein lever of p21 and p16 increased and ppRb decreased in western biot analysis. Theas results suggest that acleoside possess the activity of inducing differentiation in HL-60 cells.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 I
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• pp.230-233
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• 2003

In this paper, it is shown that, in DS/CDMA mobile systems, halving or doubling the spreading factor (HSF or DSE) when retransmission is requested possibly improves the throughput. Given transmit power, DSF essentially decreases probability of packet error (PPE) by increasing the signal energy per information bit. It, however, doubles the time duration needed for transmitting the original packet. On the other hand, HSF increases PPE. It, however halves the time duration required to carry the original packet. Thus, the efficiency of HSF or DSF as a retransmission strategy depends on the amount of increased or reduced PPE after HSF or DSF is selected. With achieving given residual error probability (REP) in CDMA systems, the effective throughput is evaluated in this paper to find conditions with which HSF or DSF achieves better performance than using the original one. Analytic results show that HSF or DSF performs better when relatively small or big changes in their PPE's are present, respectively.

• Clinical and Experimental Reproductive Medicine
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• 제38권1호
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• pp.31-36
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• 2011

Objective: To determine whether the serum ${\beta}$-human chorionic gonadotropin (hCG) profile following preimplantation genetic diagnosis (PGD) is lower than that of intracytoplasmic sperm injection (ICSI) cycles. Methods: A total of 129 PGD cycles and 1,161 age-matched ICSI cycles, which resulted in pregnancy (serum ${\beta}-hCG{\geq}5$ mIU/mL) on post-ovulation day (POD) 12 were included. We compared the mean serum ${\beta}$-hCG levels on POD 12, 14, 21, and 28, doubling time of serum hCG, and created a cut-off value for predicting a singleton pregnancy in each group. Results: The mean serum ${\beta}$-hCG concentration of the PGD group was significantly lower than that of the control group on POD 12, 14, and 21. The doubling time of serum ${\beta}$-hCG at each time interval showed no significant difference. The cut-off-value of serum ${\beta}$-hCG for predicting a single viable pregnancy was 32.5 mIU/mL on POD 12 and 113.5 mIU/mL on POD 14 for the PGD group, which was lower than that for the control group. Conclusion: Blastomere biopsy may decrease the ${\beta}$-hCG-producing activity of the trophoblasts, especially in early pregnancy. Setting a lower cut-off value of serum ${\beta}$-hCG for predicting pregnancy outcomes in PGD may be needed.

• Journal of Microbiology and Biotechnology
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• 제8권5호
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• pp.536-539
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• 1998

The anti-complementary activity (immuno-stimulating activity) was tested for the exo-polymers (extra-cellular polymer) produced from submerged mycelial cultures of 21 types of higher fungi. Anti-complementary activity of the exo-polymer from Cordyceps militaris showed the highest (69.0%) followed by Pleurotus ostreatus (63.7%) and Trametes suaveolens (61.4%). The mycelial growth rate and biomass doubling time of C. militaris in a 5 I air-lift fermenter were 0.0255 $h^{-1}$ and 27.2 h, respectively. The yield of the exo-polymer produced from the culture broth of C. militaris was 2.95 mg of dry weight/ml of culture broth. Sugar and amino acid compositions of this exo-polymer were analyzed.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 추계학술대회 논문집
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• pp.321-321
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• 2009

This paper presents quasi-zero-stiffness (QZS) characteristic of a passive isolator using flexures under compression force. The passive isolator consists of a positive stiffness element (a vertical coil spring) and a negative stiffness element (flexures under compression force), and their proper combination of the positive and negative stiffness elements can produce both substantial static and zero dynamic stiffness, so called QZS. Firstly, a nonlinear dimensionless expression of a flexure under compression force is derived. A dynamic model of the passive isolator is developed and numerical simulations of its time and frequency response are performed. Then, undesirable nonlinear vibration is quantified using a period doubling bifurcation diagram and a Poincare's map of the isolator under forced excitation. Finally, experiments are performed to validate the QZS characteristic of the passive isolator.

• Asian-Australasian Journal of Animal Sciences
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• 제17권10호
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• pp.1338-1343
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• 2004

The Debao pony ear marginal tissue fibroblast cell line (NDPEM 2/2) was uccessfully established using either primary explant technique or collagenase technique. The characterizations of the cell line were identified as following: the cells were adherent and of density limitation; population doubling time (PDT) of cells made with the two techniques were 35.9 h and 48 h, respectively; chromosome analysis showed that the frequency of cell chromosome number to be 2n=64 was 91.3%-92.8%. Confirmed by isoenzyme analysis, this cell line had no cross- contamination. Tests for microbial contamination from bacteria, fungi, virus or mycoplasma were negative. This newly established cell line meets all the standard quality controls of ATCC. It will provide a precious genetic resource for the conservation of the Debao pony breed, as well as effective experimental material for genetic studies on Debao ponies.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 V
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• pp.2835-2838
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• 2003

We study the characteristics of oscillating in non-autonomous condition and the conducted noise generation in a RL-photocoupler circuit. This circuit may be shown a period-doubling and a chaos dynamics under any specific conditions of input circuit. But, the relationship between input signals and output signals is different according to the amplitude of driving input voltage. Then, the oscillation noise was analyzed with respect to both the frequency and the amplitude of an external ac signal and do values. The results show that the noise-induced oscillations for falling and rising cycles induced by kick-back effect in an inductor, nonlinear capacitance, nonlinear resistance and charge storage time in a diode and an LED. We also compared the simulation with the experimental results.