• 한국식품영양학회지
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• 제12권3호
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• pp.233-239
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• 1999

To develop the potential use as new host strain for gene cloning the optimal conditions for transform-ation of alkali-tolerant Bacillus sp. were examined. The Bacillus sp. YA-14 was cultured to late logarith-mic growth phase at 37$^{\circ}C$ in modified SPI medium (pH8.0) containing 0.4% MgSO4 0.5mM CaCl2 1 ml of competent cell was mixed with 0.5$\mu$g of plasmid DNA and incubated with shaking at 37$^{\circ}C$ for 40min. The transformation frequency under the optimal condition was 4.53$\times$10-6 CFU/ml/g plasmid DNA. The electrophresis and stably maintained in the new host.

• 한국균학회지
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• 제25권3호통권82호
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• pp.209-218
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• 1997

저령의 균사생장은 $20^{\circ}C$의 온도와 pH 4의 조건에서 가장 양호하였으며, Hoppkins 배지에서 생장이 가장 양호하였다. Glucose, Fluctose 및 Manitol과 같은 탄소원이 저령의 양호한 생장을 촉진하였다. 또한, 진소원의 하나인 Valine도 저령의 균사생장을 촉진하였다. 배지에 탄소원을 1%로 고정시킨후 C/N비를 30:1로 하였을 때, 저령의 균사의 생장이 가장 양호하였다. 유기산으로서 Lactic acid를 처리 하였을때 저령의 생장이 좋았으며, 비타민으로는 Thiamine-Hcl을 처리하였을때 생장이 양호하였다. $FeSO_4$ 및 $MgSO_4$같은 미량원소의 처리에서 저령의 생장이 가장 양호하였다. 저령의 최적생장을 위한 미량원소의 농도는 $FeSO_4$를 첨가할 경우에는 0.01%였고, $MgSO_4$를 첨가할 경우에는 0.1%였다. 처리된 4종의 식물질 추출배지 중에서, 쌀 추출물과 번데기가루를 혼합 처리한 배지가 저령의 양호한 균사 생장을 나타내었다.

• 한국공간구조학회논문집
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• 제16권4호
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• pp.91-100
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• 2016

A retractable-roof spatial structure is frequently used for a stadium and sports hall. A retractable-roof spatial structure allows natural lighting, ventilation, optimal conditions for grass growth with opened roof. It can also protects users against various weather conditions and give optimal circumstances for different activities. Dynamic characteristics of a retractable-roof spatial structure is changed based on opened or closed roof condition. A tuned mass damper (TMD) is widely used to reduce seismic responses of a structure. When a TMD is properly tuned, its control performance is excellent. Opened or closed roof condition causes dynamic characteristics variation of a retractable-roof spatial structure resulting in off-tuning. This dynamic characteristics variation was investigated. Control performance of a passive TMD and a smart TMD were evaluated under off-tuning condition.

• ALGAE
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• 제19권2호
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• pp.145-148
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• 2004

As a result of the 2-year monthly monitoring of the phytoplankton community at 3 stations in Mankyeong Estuary, Korea, we learned that cyan bacterial species of the genus Anabaena occurred at most sampling points with huge salinity differences (0.1-32.5 psu). We isolated several clones of Anabaena spp. from the monitoring stations, and screen out two euryhaline and nitrogen-fixing Anabaena clones, CB-MAL21 and CB-MAL22. The two clones were grown under various environmental gradients such as temperature (20, 30, 35 and 40$^{\circ}C$), salinity (0, 2, 5, 15 and 30psu), and $PO_4^{3-}$-P concentration (0, 1.6, 8.0, 40 and 200 ${\mu}M$M). Growth of CB-MAL21 and CB-MAL22 was measured by daily monitoring of chlorophyll fluorescence from each experimental culture for more than three serial transfers. Both the two experimental clones did not grow at 0psu. Maximal growth rates of the two clones were markedly reduced at lower $PO_4^{3-}$-P concentrations showing negligible growth at 0 and 1.6 ${\mu}M$M. However, growth of CB-MAL21 was not affected by low $NO_3^--$ concentration in culture media, showing the nitrogen-fixing ability. Maximum biomass yields of the two clones decreased dramatically at 35 and 40$^{\circ}C$. Optimal growth conditions for the two experimental clones were determined to be 20-30$^{\circ}C$, 40 ${\mu}M$M $PO_4^{3-}$-P, and wide salinity range from 5.0 to over 30psu. Best growth of CB-MAL21 was shown at (20$^{\circ}C$-15psu), which is less saline and cooler condition than those (i.e., 30$^{\circ}C$-30psu) for the best growth of CB-MAL22. The euryhaline and nitrogen-fixing CB-MAL21 strain thus can be a candidate laboratory culture for the future cyan bacterial marine biotechnology in temperate coastal waters.

• 한국미생물·생명공학회지
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• 제9권4호
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• pp.225-230
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• 1981

The kinetic study of rifamycin B production in batch culture of Nocardia mediterranei was undertaken in part of our endeavor to optimize the fermentation condition. The growth parameters such as $\mu$$_{m}$ and Ks values for nitrogen source were evaluated by employing Monod equation. From the experiments, $\mu$$_{m}$ and Ks were 0.15hr$^{-1}$ and 8.35g/1, respectively. The growth kinetics in batch culture was found successfully interpreted by logistic law, i.e., the initial specific growth rate and the maximum cell mass concentration were determined as function of pH and both found to have maxima. For the production of rifamycin B, a non-growth associated production kinetics was employed and the specific productivity as a function of pH was found to have two maximum points. The yield coefficient and the specific productivity were calculated as mean values in production phase. Utilizing these experimental data as a function of pH, the optimal condition for the rifamycin B production was discussed with regad to the pH effect on the cell growth and production of the antibiotic. As a result, growth phase at pH 6.5 and production phase at pH 7.0 were found to be recommended.ded.

• 한국토양비료학회지
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• 제50권5호
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• pp.409-421
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• 2017

Recently Unmanned Aerial Vehicle (UAV) technology offers new opportunities for assessing crop growth condition using UAV imagery. The objective of this study was to select optimal vegetation indices and regression model for estimating of rice growth using UAV images. This study was conducted using a fixed-wing UAV (Model : Ebee) with Cannon S110 and Cannon IXUS camera during farming season in 2016 on the experiment field of National Institute of Crop Science. Before heading stage of rice, there were strong relationships between rice growth parameters (plant height, dry weight and LAI (Leaf Area Index)) and NDVI (Normalized Difference Vegetation Index) using natural exponential function ($R{\geq}0.97$). After heading stage, there were strong relationships between rice dry weight and NDVI, gNDVI (green NDVI), RVI (Ratio Vegetation Index), CI-G (Chlorophyll Index-Green) using quadratic function ($R{\leq}-0.98$). There were no apparent relationships between rice growth parameters and vegetation indices using only Red-Green-Blue band images.

• The Korean Journal of Ceramics
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• 제3권4호
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• pp.257-262
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• 1997

Aluminum nitride(AIN) thin films were deposited on SiO$_2$/Si substrates by reactive sputtering for the application of SAW devices. The major deposition parameters such as pressure, nitrogen fraction, rf power, substrate distance were changed to find out the optimal condition for c-axis oriented thin films on an amorphous substrate. The effects of deposition parameters on the crystal structure, residual stress, and growth morphology of thin films were characterized by XRD, SEM, and TEM. The FWHM of (002) rocking curve of the films deposited at the proper condition was lower than 2.2$^{\circ}$(C=0.93$^{\circ}$). Cross-sectional TEM showed that self-aligned structure was developed just after slightly random growth at the initial stage. The frequency characteristics of test device fabricated from AIN thin films confirmed their piezoelectric property and applicability for SAW devices.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.355-358
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• 2001

팽나무버섯균의 배양환경조사에서 최적배양온도는 $20^{\circ}C$, pH는 $6.0{\sim}7.5$ 탄소원은 yellow sugar. potato starch. 질소원은 soybean flour. Yeast extract. 무기염류는 $KH_2PO_4,\;MgSO_4,\;7H_2O$를 0.05%(w/v)에서 우수한 생장을 나타냈다. 액체종균 배양 실험에서는 전 배양시 erlenmeyer flask에서 6 일간 $21^{\circ}C$, 125rpm으로 배양 후 본 배양시 5% 접종량, 1.0vvm 통기로 4-5 일 배양하였을 때 균체량이 높게 나타났다.

• Archives of Plastic Surgery
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• 제37권5호
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• pp.509-518
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• 2010

Purpose: Major drawbacks of conventional bone marrow stromal cells (BSCs) transplantation method are mainly caused by direct transplanted cell to host cell interactions. We hypothesized that separation of the transplanted cells by a microporous membrane might inhibit most of the potential adverse effects and induce superior effect. The purpose of the study is to determine the optimal condition of the microporous membrane. Methods: First, BSCs were placed in polyethylene terephthalate (PET) transwell inserts with 3, 8, or $12{\mu}m$ pore size, and cultured in 24 well culture plates. After 5 days, bottoms of the plates were observed for presence of attached BSCs in monolayer and cell numbers were evaluated. Second, BSCs were placed PET, polycarbonate (PCT), and mixed cellulose esters (MCE) transwell inserts with 3 and $8{\mu}m$ pore size, and cultured in 24 well culture plates. After 3 days, the supernatants of the media left in culture plate were analyzed for collagen, vascular endothelial growth factor (VEGF), platelet derived growth factor BB (PDGF-BB), and basic fibroblast growth factor (bFGF). Third, BSCs were placed in 15% and 70% of the PET membrane with $3{\mu}m$ pore size. All the experimental conditions and methods were same as the second study. Results: The optimal pore sizes to prevent BSC leakage were $3{\mu}m$ and $8{\mu}m$. The amounts of type I collagen and three growth factors tested did not show significant differences among PET, PCT, and MCE groups. However, the collagen, VEGF, and bFGF levels were much higher in the high (70%) density group than in the low (15%) density group. Conclusion: This study revealed that the optimal pore size of membrane to prevent direct BSC to recipient cell contact is in between $3{\mu}m$ and $8{\mu}m$. Membrane materials and pore sizes do not influence the collagen and growth factor passage through the membrane. The most striking factor for collagen and growth factor transport is pore density of the membrane.

• 한국미생물·생명공학회지
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• 제26권2호
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• pp.130-136
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• 1998

참당귀 세포(Angelica gigas H4)를 현탁배양하여 면역 증강성 다당을 생산하기 위한 최적배지 설계 및 생산조건 최적화 연구를 수행하였다. 우선 세포의 성장에 가장 좋은 배지로서 Schenk and Hildebrandt(SH) 배지를 선택하여 배양한 결과 $25^{\circ}C$, 암배양조건에서 각각 15.8g DCW/l와 0.85 g/l의 세포 및 다당을 얻을 수 있었다. 한편 다당 생산용 배지의 개발을 위하여 여러 가지 식물세포배양용 배지 중에서 다당 생산능이 가장 높은 배지로서 Gamborg B5 배지를 선정하였으며 B5 배지를 변형하여 면역증강성 다당생산을 위한 최적배지(PPM)를 개발하였다. 그리고 최적배지를 이용한 당귀 세포증식과 다당 생산을 위한 최적 pH는 6.0-6.5, 배양온도는 $20^{\circ}C$, 그리 고 광조건보다는 암조건이 좋은 것으로 밝혀졌다. 상기 최적조건에서의 최대 세포증식과 다당생산은 각각 14.8 g/l, 1.5 g/l 이었다.