• 대한소아치과학회지
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• 제24권1호
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• pp.325-336
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• 1997

The purpose of this study was to evaluate the compensation effect of exposure duration increase to decreased light intensity of visible-light curing unit. The specimen with 2mm thickness was made of Restorative $Z-100^{TM}$ (A2 shade, 3M Dental Products, U.S.A.) and cured with $Optilux^{TM}$ (Demetron Research Co. U.S.A.). The light intensity was controlled to 420 $mW/cm^2$, 540 $mW/cm^2$, 630 $mW/cm^2$ and curing time, also, controlled to 40, 60, 80 seconds. Cured specimen was stored in a light-proof container for 24 hours to post-irradation was completed. Microhardness of top and bottom surface of specimen were measured to evaluate the depth of cure. The obtained results were as follows: 1. The microhardness of top and bottom surface of the composite resin specimen was increased significantly as light intensity and exposure time was increased (P<0.01). 2. Light intensity was more correlated with bottom microhardness(${\gamma}{\geq}$0.438) than top microhardness(${\gamma}{\geq}$0.213), and exposure time was more correlated with top microhardness (${\gamma}{\geq}$0.424) than bottom microhardness(${\gamma}{\geq}$0.335). 3. The regressive equation was obtained in this study as follows : $H=0.07{\times}D+0.012{\times}I+76$ (H : Microhardness(KHN), D : Exposure time, I : Light intensity)

• 한국임상약학회지
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• 제7권1호
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• pp.45-49
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• 1997

The effect of the light on the stability of 5-fluorouracil admixture was investigated. Four sets of 5-fluorouracil admixture were prepared using 50 mg/ml injection in $5\%$ dextrose solution in PVC bags and glass bottles: (1) 5-fluorouracil 1 mg/ml concentration in glass bottles, (2) 5-fluorouracil 1 mg/ml in PVC bags, (3) 5-fluorouracil 10 mg/ml in glass bottles, and (4) 5-fluorouracil 10 mg/ml in PVC bags. In each set, one group was protected from the light (control group) and the other group was exposed to the fluorescent light (study group). All admixtures were stored at room temperature for 72 hours. Also, 5-fluorouracil injections (50 mg/ml) were prepared in plastic syringes. Half of the samples of 50 mg/ml concentration were protected from the light (control group) and the other half were exposed to the fluorescent light (study group). These were stored at room temperature for 48 hours. After visual inspection, the pHs of each admixture were determined. The 5-fluorouracil concentrations were measured by high-performance liquid chromatography with UV detection, with 5-bromouracil as an internal standard. Over the study period, no visual changes were observed. The pHs of 5-fluorouracil admixtures were in the range of $8.2\~8.5$. The peak area ratios (5-FU/5-BrU) of 5-fluorouracil admixtures protected from the light were compared with those of the admixtures exposed to the light. There was no statistically significant difference between two groups during the study period (p>0.05). In conclusion, 5-fluorouracil admixtures in $5\%$ dextrose solution exposed to the light were stable for 72 hours.

• Fisheries and Aquatic Sciences
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• 제19권6호
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• pp.28.1-28.7
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• 2016

Background: Significant increases in the bacterial resistance to various antibiotics have been found in fish farms. Non-antibiotic therapies for infectious diseases in aquaculture are needed. In recent years, light-emitting diode technology has been applied to the inactivation of pathogens, especially those affecting humans. The purpose of this study was to assess the effect of blue light (wavelengths 405 and 465 nm) on seven major bacterial pathogens that affect fish and shellfish important in aquaculture. Results: We successfully demonstrate inactivation activity of a 405/465-nm LED on selected bacterial pathogens. Although some bacteria were not fully inactivated by the 465-nm light, the 405-nm light had a bactericidal effect against all seven pathogens, indicating that blue light can be effective without the addition of a photosensitizer. Photobacterium damselae, Vibrio anguillarum, and Edwardsiella tarda were the most susceptible to the 405-nm light (36.1, 41.2, and $68.4J\;cm^{-2}$, respectively, produced one log reduction in the bacterial populations), whereas Streptococcus parauberis was the least susceptible ($153.8J\;cm^{-2}$ per one log reduction). In general, optical density (OD) values indicated that higher bacterial densities were associated with lower inactivating efficacy, with the exception of P. damselae and Vibrio harveyi. In conclusion, growth of the bacterial fish and shellfish pathogens evaluated in this study was inactivated by exposure to either the 405- or 465-nm light. In addition, inactivation was dependent on exposure time. Conclusions: This study presents that blue LED has potentially alternative therapy for treating fish and shellfish bacterial pathogens. It has great advantages in aspect of eco-friendly treating methods differed from antimicrobial methods.

• 생물환경조절학회지
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• 제10권1호
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• pp.55-60
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• 2001

일몰 후 적색 및 원적색 광처리가 토마토 묘 소질에 미치는 효과를 조사하기 위해 24일간의 광처리 기간동안 12일 간격으로 묘의 초장, 제1절간장, 줄기직경을 측정하였고, 실험 마지막 날에는 묘의 뿌리와 줄기를 분리 건조하여 각 건물중을 측정하였다. 적색광 처리는 식물의 초장을 억제시키는 것으로 나타났고, 원적색광 식물의 초장신장을 촉진하는 결과를 보였다. 적색 및 원적색광 처리가 식물의 초장에 미치는 효과는 광처리 시간이 10분 또는 20분이든 큰 차이가 없었다. 또한, 적색광 처리된 식물의 줄기직경이 대조구 및 원적색광 처리된 식물의 줄기 직경보다 큰 것으로 나타났다. 적색광 처리는 원적색광 처리 및 대조구에 비해 줄기·뿌리의 건물중비가 작았다. 토마토 묘의 충실도에 미치는 광처리 효과는 적색광 처리가 가장 우수한 것으로 나타났고, 원적색광 처리된 묘의 충실도가 가장 낮았으며 광처리 없는 대조구는 그 중간정도의 충실도를 나타내었다.

• 한국의상디자인학회지
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• 제13권3호
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• pp.1-14
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• 2011

A dress is commonly designed and worn as a work of art. It is developed through various ways to show the expression of our bodies with functional aspects. Light plays a role in everyday life functionally and aesthetically. We can use the light in many different ways in order to enhance the beauty of the designs. The purpose of this study is to suggest sensible designs with the active expression of light reflection. The designs are especially focused on utilizing light that shows the combination between natural human body's movement and reflection of the light. The use of reflective materials shows the character of movement when it exposes to light. The methods allow to amplify the aesthetic effects of the designs. Reflective materials were used in the resulting design to show the various effects of light by applying the movement which is artistic and aesthetic pleasing aspect for the clothing. The movement is accentuated when the wearer moves, or the air flows through the adding materials on the clothing. In addition, the beads attached to the end of the springs to show the movement of the light. The combination of the spring and the light movement resulted in a dazzling effect. I hope in the future, more studies will be conducted to further use of fiber optics and other innovative ways to use light in fashion.

• Journal of Plant Biotechnology
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• 제43권1호
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• pp.119-124
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• 2016

Anthocyanin accumulation and plant growth were examined in petunia (NT and $T_2$ transgenic plants) by determining the effects of different sources of light and varying light/dark cycles. Red light significantly enhanced anthocyanin content of B-peru+mPAP1; however, it had a negative effect on anthocyanin production in RsMYB1 plants. In general, white light was found to be reasonable for anthocyanin accumulation in all plants. In case of light/dark cycles, application of seven days of light:14 days of dark significantly enhanced anthocyanin content. We found that anthocyanin content detected in transgenic plants expressing anthocyanin regulatory transcription factor genes (B-peru+mPAP1 or RsMYB1) was higher than that in NT plants in all treatments. Plant growth was also influenced by the different light sources and dark/light cycles. Taken together, our results suggest that light source and light/dark cycle play an important role in anthocyanin production and plant growth. The choice of the optimal conditions is also important for anthocyanin production and plant growth depending on NT or transgenic plants carrying anthocyanin regulatory transcription factors.

• Journal of Applied Biological Chemistry
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• 제44권2호
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• pp.84-86
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• 2001

Capsaicin synthesis by suspension cultured cells of Jalapeno pepper (Capcicum annuum L.) was assessed in vitro under various conditions including temperature (23 and $30^{\circ}C$), light intensity (with light and without light), and shaking speed (110 and 200 rpm). Capsaicin production increased, while the cell biomass growth decreased possibly due to the production of a secondary metabolite. Capsaicin synthesis was primarily affected by light condition. Cells cultivated at 110 rpm and $23^{\circ}C$ under light condition yielded the highest fresh weight, while those cultivated under the same condition, but without light resulted in the lowest cell mass. Capsaicin content in cells of 18-day-old pepper grown at 110 rpm and $23^{\circ}C$ under light was 0.125% of the cell mass. However, without light treatment, the capsaicin content in cells at the same shaking speed and temperature increased up to 169%, indicating no light is favored in the capsaicin synthesis by Jalapeno pepper. Increasing the shaking speed from 110 to 200 rpm without light enhanced the capsaicin synthesis. Results of this study demonstrate that light condition is the limiting factor in the synthesis of capsaicin in tissue-cultured Jalapeno pepper cells.

• 한국디지털건축인테리어학회논문집
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• 제8권1호
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• pp.65-74
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• 2008

Light creates ambiance that affects our impression of space. Before the modern age, the role of light is a religious factor and a primitive state to see. In the modern space design, light is used to achieve the continuous transformation and translation of building's image. Ever-changing space is a flexible corresponding of space to its environment, caused by certain dynamic light. The space turn into some other thing from what it was before, or just changing its character. approaching men and society with different meanings. The purpose of this study is to explore the relation between light(natural and artificial) and ever-changing space through the case study. The impacts of light on ever-changing in today's space design can be summarized as follows. 1) Materialization of light in space design. Nowadays light becomes a form itself. The geometric properties of the space form playa secondary role as compared to the importance assigned to light. 2) Pixelization of space by a light effect. The impacts of digital technology on the space design have come through enhancing the 'pixelization' of the surface from which buildings are made their responsiveness and adaptability to changing needs. The surface with ever-changing lights that blur the boundary of space and expand the image of space.

• 한국자원식물학회지
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• 제25권6호
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• pp.739-744
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• 2012

The plant Empetrum nigrum, valued in the traditional system of medicine, is well known for its antibacterial, antifungal, and antioxidant properties. In the present work, the effect of removal of shoot apical meristem (SAM) on shoot proliferation was studied. It was observed that removal of SAM promoted shoot proliferation whereas intact tip resulted in higher survival percentage. Further, the effect of different concentrations of BA on above was also studied. During root formation the effect of light quality after treatment with IBA was investigated. For rooting, continuous red light without IBA resulted in maximum rooting percentage. The above factors when taken into consideration during micropropagation of this endangered plant can result in healthier plantlets. The results show that the species could be successfully conserved by in vitro propagation system.

• Bulletin of the Korean Chemical Society
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• 제34권6호
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• pp.1845-1847
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• 2013

The lateral photovoltaic effect (LPE) can be observed in semiconductors by irradiating a light spot position between electrodes on sample's surface. Because lateral photovoltaic voltage (LPV) is sensitively changed by light spot position, a LPE device has been tried as a position-sensitive detector. This study discusses the correlation between LPV and conductivity in p-type silicon and nano-structured Au deposited p-type silicon (nano-Au silicon), respectively. Conductivity measurement of the sample was carried out using the four-wire method to eliminate contact resistance, and conductivity dependence on LPV was simultaneously measured by changing the light irradiation position. The result showed a strong correlation between conductivity and LPV in the p-type silicon sample. The correlation coefficient was 0.87. The correlation coefficient between LPV and conductivity for the nano-Au silicon sample was 0.41.