• Journal of Nutrition and Health
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• 제16권4호
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• pp.273-280
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• 1983

The effect of alteration of light-darkness cycle on the protein metabolism was studied in the rat. The light-darkness cycle was altered either every 3 or 9 days, and animals consumed diets containing 8 or 25% casein. The results were summarized as follows : 1) Food consumptions and body weight gains of the 25% casein groups were higher than those of the 8% casein groups, and, among the animals consumed 25% casein diet, the light-darkness cycle altered group had lower food consumption and body weight gain than the unaltered group. 2) Weights of liver and adrenal gland per l00g body weight were not different with the dietary protein levels, but, at the end of experimental period, the 8% casein diet group of which light-darkness cycle altered every 9 days had the smallest liver weight and the largest adrenal gland weight. 3) Liver nitrogen and plasma protein concentrations of the 25% casein groups were slightly higher than those of the 8% casein groups. 4) Percentages of nitrogen retention of the 25% casein groups at period III were slightly lower in the light-darknerr cycle altered animals than that of the unaltered group.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2001년도 추계학술대회(제116회) 및 13회 Workshop 제3회 한ㆍ일 치과보존학회 공동학술대회 초록집
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• pp.578.1-578
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• 2001

The aim of this study was to evaluate the efficiency of the recently introduced light curing units to polymerize a light curing resin composite. Four light curing units XL 3000, Optilux 500 for halogen light source, Apollo 95E for plasma arc and Easy cure for LED (blue-light Emitting Diode) were evaluated. Radiometer was used for measure the light intensity.(omitted)

• 한국자동차공학회논문집
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• 제8권6호
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• pp.87-100
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• 2000

HC and CO emissions during the cold start contribute the majority of the total emissions in the legislated driving cycles. Therefore, in order to minimize the cold-start emissions, the fast light-off techniques have been developed and presented in the literature. One of the most encouraging strategies for reducing start-up emissions is to place the light-off catalyst, in addition to the main under-body catalyst, near the engine exhaust manifold. This study numerically consider three-dimensional, unsteady compressible reacting flow in the light-off and under body catalyst to examine the impact of a light-off catalyst on thermal response of the under body catalyst and tail pipe emission. The effect of flow distribution on the temperature distribution and emission performance have also been examined. The present results show that flow distribution has a great influence on the temperature distribution in the monolith at the early stage of warm-up process and the ultimate conversion efficiency of light-off catalyst is severly deteriorated when the space velocity is above $100,000hr^{-1}$.

• 환경생물
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• 제41권4호
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• pp.697-705
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• 2023

Along with other heavy metals, arsenic (As) is one among the substances most harmful to living organisms including humans. Owing to its morphological similarity to phosphorus, the uptake of As is influenced by photosynthesis and the phosphorus uptake pathway. In this study, we varied arsenic exposure and light intensity during nutrient solution cultivation of lettuce (Lactuca sativa L.) to determine the effect of these two factors on arsenic uptake, lettuce growth, and electron transfer in photosystem II. In the treatment exposed to 30 μmol L^-1 of arsenic, the shoot arsenic concentration increased from 4.73 mg kg^-1 to 18.97 mg kg^-1 as the light intensity increased from 22 to 122 μmol m^-2 s^-1. The water content and ET2o/RC of the shoots were not affected by arsenic at low light intensity; however, at optimal light intensity, they decreased progressively with arsenic exposure. Increased light intensity stimulated the growth of plant roots and shoots; contrarily, the difference in growth decreased as the concentration of As exposure increased. The results of this study suggest that the effect of As on plant growth is dependent on light intensity; in particular, an increase in light intensity can increase the uptake of As, thereby affecting plant growth and As toxicity.

• 한국콘텐츠학회논문지
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• 제10권2호
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• pp.130-137
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• 2010

Light Drawing은 사진 촬영 기법 중 하나로, 어두운 방이나 밤에 빛이 나는 물체의 움직임을 노출 기법을 이용하여 촬영 한 것이다[1]. 사용자가 Light Drawing을 만들려 한다면 장 노출 카메라가 필요하고, 어두운 환경이 필요함으로 제한사항이 따르며 사용자는 3차원 공간에 그림을 그리는 것에 어려움을 느낀다. 반면에 포토�斌� 같은 컴퓨터 드로잉 툴을 사용하여 Light Drawing 효과를 낼 수 있다. 그러나 마우스나, 타블렛과 같은 입력 장치는 실제로 그림을 그리는 행위와 차이가 나기에 사용자들의 흥미를 반감시킨다. 본 논문에서는 Light Drawing을 손쉽게 제작 가능한 디지털 컨텐츠를 제안한다. 스테레오 비전을 이용하여 빛의 3차원 위치 정보를 계산하고 Drawing Effect를 이용하여 3차원 가상 공간에 Light Drawing을 구현하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제15권8호
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• pp.1182-1185
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• 2002

The objective of this study was to investigate the effect of long light regime (20 h light and 4 h dark, 20L:4D) and short light regime (4 h light and 20 h dark, 4L:20D) on egg production and egg characteristics of laying geese. Thirty-six laying birds, 4 replicates of 3 birds per treatment were allotted to three light regimes, i.e., 20L:4D, 4L:20D, and natural light (NAT) from March 7 to June 20. Results showed that the geese in 20L:4D consumed 54 g less feed per goose daily and laid 17.5 less eggs per goose (p<0.05) comparing to those in 4L:20D. The number of days from initiation of light treatment till cease of laying was 22 days shorter (p<0.05) in 20L:4D comparing to that in NAT. Five geese (41.7%) in 4L:20D kept laying by the end of applying light regime. Weight and surface area of the eggs in 4L:20D were greater (p<0.05) comparing to those in the other two light regimes. It is concluded that the period of egg production in goose could be manipulated by light regime in the ways such as using short light regime of 4 h light daily to prolong egg production through summer and using long light regime of 20 h light daily to induce cease of egg production.

• 대한화장품학회지
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• 제44권2호
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• pp.183-189
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• 2018

블루라이트는 가시광선영역의 파장 중 가장 에너지가 높은 파장으로 피부노화 유발 및 활성산소를 유발하는 것으로 알려져 있으며, 피부의 유해 기작에 관한 연구가 진행 중이다. 화장품 분야에서의 블루라이트 차단소재 연구 및 관련 제형연구는 아직 초기 단계에 있으며, 블루라이트 차단 측정과 관련된 시험법 또한 명확하게 정립되어 있지 않다. 블루라이트 차단 효능 평가 시험법은 해외 자외선 차단제의 차단효과 평가 방법을 참고하여 확립하였다. 국내에 고시되어 있는 자외선 차단제 원료 27종 중 17종에 대하여 블루라이트 차단효과를 평가하였으며, 블루라이트 차단 효과는 징크옥사이드가 14.97%, 비스에칠헥실옥시페놀메톡시페닐트리아진이 16.32%, 메칠렌비스-벤조트리아졸릴테트라메칠부틸페놀이 35.47%, 티타늄디옥사이드가 65.96% 순으로 나타났다. 또한 동일 함량의 티타늄디옥사이드의 입자크기에 따른 블루라이트 차단효과를 확인한 결과 Nano-티타늄디옥사이드 보다 Micro-티타늄디옥사이드가 두 배 이상의 차단효과가 높게 나타냈다. 제시된 블루라이트 차단효과 평가 시험법은 블루라이트 차단 소재 탐색 및 화장품 제형 연구에 활용될 수 있을 것이다.

• 수산해양기술연구
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• 제47권4호
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• pp.316-326
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• 2011

In this study, the entrapped number is investigated on the UV light with different illuminance to fluorescent bait cage for swimming crab in order to find the appropriate illuminance which has the best attraction effect of fluorescent bait cage for pots. In addition, preference to the light, arrival time and residence time at light area are compared and analyzed to fluorescent bait cage and non-fluorescent bait cage for American lobster at the UV light and ordinary light according to the illuminance condition. Pot with red non-fluorescent bait cage at the no lighting (<0.01lux), pot with blue fluorescent bait cage at the 20W UV lighting (0.16lux) and pot with blue fluorescent bait cage at the 30W UV lighting (0.22lux) were soaked for 6 hours and the entrapped number of swimming crab was examined. The mean entrapped number of swimming crab in pot with red non-fluorescent bait cage at the no lighting (<0.01lux) was 1.0, but the mean entrapped number of swimming crab in pot with blue fluorescent bait cages at the 20W UV lighting (0.16lux) and 30W UV lighting (0.22lux) were 1.4 and 0.4, respectively (P<0.05). The rate of preference to the blue fluorescent bait cage at the UV lighting shows 1.6-4.8 times higher than that of preference to the red non-fluorescent bait cage at the ordinary lighting. In addition, The rate of preference to the blue fluorescent bait cage at the UV lighting is higher when the illuminance of ordinary light is same as or is lower than that of UV light (P<0.05). However, the preference to the light depending on gender shows no significant difference (P>0.05). The arrival time to UV light area of lobster is shown as 1.2-2.4 times faster than that to ordinary light area. Generally, it is shown that arrival time to UV light area is faster than the arrival time to ordinary light area when the illuminance of ordinary light is the same as or lower than that of UV light (P<0.05). However, arrival time to the light area depending on gender shows no significant difference (P>0.05). The residence time at UV light area of lobster is 1.2-1.7 times longer than that at ordinary light area. The residence time depending on different illuminance of ordinary light and genders showed no significant difference (P>0.05).

• 천문학회지
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• 제23권2호
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• pp.106-111
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• 1990

Photoelectric observation in 1984 shows light variation outside eclipses. The effect of the changing ambient temperature on the light curves were studied. Difficulty of studying and unitary, or mean, light curve of AR Lac is stressed.

• ALGAE
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• 제37권2호
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• pp.163-174
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• 2022

Light-emitting-diodes (LEDs) are a lighting source useful for the precise evaluation of light quality effect on biological systems. Despite the importance of light spectra on the regeneration of land plant protoplasts ("naked cells"), this factor has not been tested yet on protoplasts from multicellular algae. This study reports on the effects of pure primary colors (red, blue, and green), dichromatic (red plus blue, RB, 1 : 2) and white LEDs on protoplast regeneration from male and female Undaria pinnatifida gametophytes. We also evaluated the effect of different light spectra on pigment composition (chlorophyll a, chlorophyll c, and fucoxanthine), and the light intensities under the best condition on the regeneration process. In the early stages, blue or RB LEDs increased the percentage of dividing female protoplasts, whereas red, blue, and RB LEDs enhanced that of dividing male protoplasts. In the later stages, RB LEDs showed a positive effect only on the percentage of multiple rhizoid-like protrusions (male gametophyte). They also increased the final area of both regenerated gametophytes. The LEDs did not affect pigment composition in female gametophytes. In male gametophytes, in contrast, they reduced chlorophyll c, while blue, RB, and green LEDs decreased fucoxanthin. Under RB LEDs, the optimal light intensity was 80 µmol photons m^-2 s^-1 for female gametophytes and 40 to 60 µmol photons m^-2 s^-1 for male gametophytes. Our results suggest that dichromatic LED illumination (red-blue) improves regeneration of U. pinnatifida gametophyte-isolated protoplasts. Thus, dichromatic LEDs might a suitable light source for enhancing protoplast regeneration in brown seaweeds.