• KSBB Journal
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• v.17 no.6
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• pp.571-576
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• 2002

Recombinant E. coli DH5 ${\alpha}$/pSB311 was made by cloning the genes encoding bacterial luciferase and aldehyde substrate proteins from Photohabdus luminescense, to complement defects of Lumistox, which is normally used in bioassays to monitor toxic substances in water environmental systems. The conditions for stable light production by the recombinant strains were investigated with respect to cell growth stage, cell number, and buffer conditions. The optimum growth stage was a middle-exponential stage with an OD$_{660nm}$ value of 0.6-0.7. ADout 10$^{6}$-10$^{7}$ cells per test tube was optimum for stable light emission. The effect of buffer was not significant if an optimum viable cell number was maintained. The bioluminescence of the recombinant E. coli harboring the lux operon of Photohabdus luminescense was not affected by temperature, while the bioluminescence of Lumistox was temperature sensitive. The recombinant E. coli was more sensitive to heavy metals (Cd, Cu, Hg, Zn) than Lumistox, because it does not require high concentrations of NaCl in the buffer.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.212-215
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• 2000

Recombinant bioluminescent bacterial strains that use specific promoters fused to the bioluminescence genes (lux genes) have been applied in environmental monitoring. Advantages of using recombinant bioluminescent bacteria as blosensing cells include rapid responses, low costs, and improved reproducibility. In this study, a recombinant Escherichia coli, GC2, containing a lac::luxCDABE fusion immobilized with solid agar media and glass beads was used to estimate the effect of this soil flushing technique. This bacterium constitutively emits light under normal conditions (no toxic chemicals). When growth and metabolism of these bioluminescent bacteria is inhibited by their exposure to toxic chemicals, the bioluminescence (BL) is reduced. A biosurfactant, rhamnolipids, was used to extract phenanthrene from the soil after flushing.

• Journal of Microbiology and Biotechnology
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• v.26 no.1
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• pp.66-71
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• 2016

PikD is a widely known pathway-specific regulator for controlling pikromycin production in Streptomyces venezuelae ATCC 15439, which is a representative of the large ATP-binding regulator of the LuxR family (LAL) in Streptomyces sp. RapH and FkbN also belong to the LAL family of transcriptional regulators, which show greatest homology with the ATP-binding motif and helix-turn-helix DNA-binding motif of PikD. Overexpression of pikD and heterologous expression of rapH and fkbN led to enhanced production of pikromycin by approximately 1.8-, 1.6-, and 1.6-fold in S. venezuelae, respectively. Cross-complementation of rapH and fkbN in the pikD deletion mutant (ΔpikD) restored pikromycin and derived macrolactone production. Overall, these results show that heterologous expression of rapH and fkbN leads to the overproduction of pikromycin and its congeners from the pikromycin biosynthetic pathway in S. venezuelae, and they have the same functionality as the pathwayspecific transcriptional activator for the pikromycin biosynthetic pathway in the ΔpikD strain. These results also show extensive "cross-communication" between pathway-specific regulators of streptomycetes and suggest revision of the current paradigm for pathwayspecific versus global regulation of secondary metabolism in Streptomyces species.

• Korean Journal of Microbiology
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• v.41 no.3
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• pp.236-238
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• 2005

The effect of light on production of cordycepin (3'-deoxyadenosine) was investigated using Cordyceps militaris. Among Cordyceps spp. tested, C. militaris KCTC 6064 was the best for cordycepin production, After 120-hr cultivation of C. militaris KCTC 6064 at $24^{\circ}C$ in YMG broth with light (1,000 lux), 51.6 mg/l of cordycepin was produced. In general, production of cordycepin with light illumination was better than that without light. Cordycepin production under light illumination was enhanced up 96-hr cultivation, whereas after 96-hr, cordycepin production was decreased.

• Korean Journal of Microbiology
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• v.21 no.3
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• pp.109-114
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• 1983

Physiological conditions for hydrogen evolution by Rhodopseudomonas sphaeroides K-7 are examined. Larger amount of molecular hydrogen was evolved at $30^{\circ}C$, pH6.8-7.0 under anaerobically illuminated condition of about 12, 000 lux by the organism. The heighest rates of hydrogen evolution were observed in the culture with the organic acids such as acetate, DL-lactate or DL-malate in media containing L-glutamate as a nitrogen source. Hydrogen was also evolved from glucose with the rate of $178.9\;{\mu}l/hr/mg$ cells (dry weight). When glucose was adopted a a sole carbon source, however, conside erable time lag of about 20hours was required for hydrogen evolution. The resting cells stored at $30^{\circ}C$ under argon maintained the rate of hydrogen evolution in nearly about 90% of initial one even 40 days of storation.

• Journal of Microbiology and Biotechnology
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• v.17 no.8
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• pp.1254-1261
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• 2007

In the present study, we have constructed a bioluminescent bioreporter for the assessment of nitrate/nitrite bioavailability in wastewater. Specifically, an approximately 500-bp DNA fragment containing a nitrate/nitrite-activated nasR-like promoter (regulating expression of genes encoding nitrite reductase in the genus Klebsiella) was fused upstream of the Vibrio fischeri luxCDABE gene cassette in a modified mini-Tn5 vector. Characterization of this strain, designated W6-1, yielded dose-dependent increased bioluminescence coincident with increased nitrate, nitrite, and ammonium added to the growth medium from 1 to 11 ppm. Bioluminescence in response to nitrogen species addition was light dependent up to 10, 7, and 8 ppm with nitrate, nitrite, and ammonium, respectively. This response was linear in the range from 1 to 8 ppm for nitrate ($R^2=0.98$), 1 to 6 ppm for nitrite ($R^2=0.99$), and 1 to 7 ppm for ammonium ($R^2=0.99$). A significant bioluminescent response was also recorded when strain W6-1 was incubated with slurries from aged, nitrate/nitrite contaminated wastewater. Thus, bioreporter strain W6-1 can be used to elucidate factors that constrain the use of nitrate/nitrite in wastewaters.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.53-53
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• 2018

전라북도 동부권 지역은 중산악지형으로 표고 100~500m 산지가 69%, 500~1,000m가 26%로 이루어져 있어, 산채를 재배하기에 유리한 지리적 조건을 갖고 있다. 따라서 소비자의 수요가 높은 산채류의 재배 및 이용에 대한 농업인들의 기술개발이 요구되고 있다. 이에 전라북도 준고랭지역에서 재배하기 적합한 산채작목을 선발하고자 본 시험을 실시하였다. 시험은 표고 500m 전라북도 남원시 운봉읍 허브시험장에서 노지재배, 남원시 주천면 표고 530~540m, 진안군 주천면 표고 340~350m에 위치한 농가포장에서 임간재배를 실시하였다. 대상작물은 개미취(Aster tataricus), 갯기름나물(Peucedanum japonicum), 곤달비(Ligularia stenocephala), 눈개승마(Aruncus dioicus var. kamtschaticus), 단풍취(Ainsliaea acerifolia), 산마늘(Allium microdictyon), 섬쑥부쟁이(Aster glehnii), 어수리(Heracleum moellendorffii), 우산나물(Syneilesis palmata) 등 9종을 2016년 종묘를 정식하였다. 정식 2년차에 해당지역의 5월~9월 평균기온 및 조도 등 생육환경을 조사하고, 시험작물의 출현율, 생육특성, 수량 등을 조사하였다. 조사기간 동안의 평균기온은 노지가 $20.8^{\circ}C$, 남원임간은 $20.3^{\circ}C$, 진안임간은 $20.5^{\circ}C$이었으며, 평균조도는 노지가 37,362Lux, 남원임간은 7,816Lux, 진안임간은 25,316Lux이었다. 노지에서 출현율은 개미취, 갯기름나물, 눈개승마, 산마늘, 섬쑥부쟁이, 우산나물이, 임간에서는 개미취, 곤달미, 눈개승마, 단풍취, 산마늘, 어수리, 우산나물이 높았다. 생육특성은 노지에서 개미취, 갯기름나물, 눈개승마, 섬쑥부쟁이, 임간에서는 단풍취, 산마늘, 우산나물의 생육이 좋았다. 수량은 노지에서 개미취, 갯기름나물, 곤달비, 산마늘, 섬쑥부쟁이, 어수리가 높았으며, 남원임간에서는 곤달비, 단풍취, 우산나물, 어수리가, 진안임간에서는 개미취, 갯기름나물, 산마늘, 우산나물의 수량이 많았다. 이와 더불어 준고랭지에 적합한 산채류률 선발하기 위해서는 차후 재배 지역 및 방법의 차이에 따른 산채작물의 연차별 수량성과 경제성에 관한 연구가 이루어져야 할 것으로 여겨진다.

• Journal of Korean Ophthalmic Optics Society
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• v.18 no.1
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• pp.19-25
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• 2013

Purpose: The degree of the pupil covered with tinted region of circle soft contact lens was determined according to the illuminant conditions in everyday life and the change of visual acuity by its covering was further investigated. Methods: The circle contact lens having the non-tinted area of 6.2 mm in the center of the lens was applied on 82 eyes in their 20s and their minimum separable visual acuity and minimum legible visual acuity were determined under the luminances of 50 and 370 lux. Results: The covering of pupil was not found when wearing circle contact lens under 370 lux, however, some pupil covering ranged from 0.40 to 1.70 mm was observed in all subjects under 50 lux. The minimum separable visual acuity and minimum legible visual acuity were significantly decreased by the wearing of circle contact lens under 50 lux and the correlation between the larger pupil size of subjects and more decrease of visual acuity was observed. Furthermore, the decrease of minimum separable visual acuity was larger than the case of minimum legible visual acuity indicating that minimum separable visual acuity was largely affected by the covering of pupil. Conclusions: The consideration is necessary for the lens wearers and the manufacturers since the wearing circle contact lens in low-light indoor or nighttime activities may affect directly visual acuity.

• Archives of design research
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• v.17 no.3
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• pp.353-362
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• 2004

This research has been done to evaluate the interior environmental factors in Gyungro-dang to suggest the advanced recommendations for them. For this research, the essential interior elements influencing on elderly's behavior were examined with the developed checklist, the lighting and color conditions of main hall at 14 facilities in Seoul area were analysed, and 124 subjects staying at Gyungro-dang were participated in questionaire survey for color preferences. Results showed that 1.The average installation rate of 39 items in checklist was 59%, the mandatory items such as accessible dimension were considered, but several items related to mobility and safety were not properly installed. Therefore not only guiding handrail and floor block to destination but also elimination of obstacles should be reconsidered. 2.The average of illuminances was 289 Lux dose to standard 300 Lux, but lighting quality was too low to support the activities of elderly users. The lighting control devices, combined lighting sources, and suitable lighting techniques should be applied for those facilities. 3.Most facilities were predominantly in warm colors in hue, medium or high value, low saturation, and natural atmosphere with similarity harmony. The color applications in those facilities were not functional, but similar as color preferences for the elderly except overall atmosphere. It is recommendable to include contrast harmony with classic or romantic mood.

• Journal of the Korean Society of Safety
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• v.19 no.3 s.67
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• pp.70-77
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• 2004

A Reasonable lighting should be provided for doing night work. All works far construction site can be exposed to potential hazard at night work The purpose of this study is to provide a standard of the lighting against accidents due to insufficient lighting at site. one pilot tea one at building work site, one at mad work site of it have been conducted for figuring out illumination change depending worker's activity direction, using lux checker to show it as numerical indication. The direction are changed with a range of 30, 60, 90, and 135 degree to be checked at site. Tests results show that $10\%\;and\;15\%$ of lighting could be decreased by changing the working direction of works at site. Therefore, steep slope place, cave work and backside of structural elements such as a column, deep beam should be considered for keeping sufficient and reasonable lighting. It is found that $50\%more$ illumination Lux needs f3r civil work than for building work.