• Title/Summary/Keyword: Dark adaptation

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The luring effect of the sardine bait for octopus pot in laboratory (실험실에서 문어 통발용 정어리 미끼의 유인 효과)

  • AN, Young-il
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.55 no.3
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    • pp.190-197
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    • 2019
  • This study investigated the luring effect of the sardine bait, which is used to catch octopus with pot, as the preliminary study for the development of alternative bait for octopus pot. The soaking time for bait was divided into "5 days or less" and "11 days or longer" The number of times octopus entered the pot with bait and the empty pot was investigated under dark adaptation and light adaptation processes and the distribution of tank section was investigated under light adaptation process. The case of "11 days or longer" sardine soaking time showed higher rate of distribution in the section of pot with bait compared to the case of "5 days or less" In the case of "5 days or less" soaking time, the number of times the octopus entered the pot with bait was similar to that it entered the pot without it even during dark adaptation and light adaptation. However, in the case of "11 days or longer", the octopus entered the pot with bait more quickly than the pot without bait and more frequently during dark adaptation hours. There were cases where the octopus did not enter any pot. In the case of "5 days or less", with less decomposition of baits, the octopus entered the empty pot more during light adaptation process, and it appeared that the pot was used as a hideout.

A Study of a Decay Parameter for the Dark Adaptation Function on the retina (망막에서 암순응 함수의 Decay parameter 연구)

  • Kim, Yong Geun
    • Journal of Korean Ophthalmic Optics Society
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    • v.5 no.2
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    • pp.145-150
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    • 2000
  • The adaptation for a right source on the retina consists of the light-dark adaptation's two curves for a time by the rod-cone receptor. We obtained the adaptation for a time to measure the threshold intensities, it was two decay curves by the center of a rod-cone break. It could be represented the dark adaptation by a exponential decay function consisting of $T_{min}$, $a_r$, $a_c$, $T_{0(r)}$, $T_{0(c)}$, $t_b$, $t_c$'s parameters. The curves of a $t_b$ below and a $t_b$ above showed the adaptation sensitivity of the cone and the rod. The exponential decay function was well applied to the dark adaptation in difference retinal positions, in contrally fixated fields, in luminous, as age etc. It could be used the decay parameter as the index because of representing the properties of the dark adaptation's function.

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Effects of Illumination and Target Size on Time-To-Detect while Recovering Dark Adaptation (암순응 환경에서 조도수준과 표적크기가 탐지시간에 미치는 영향)

  • Park, Jae-Kyu;Park, Sung-Ha;Oh, Hyun-Seung
    • Journal of the Ergonomics Society of Korea
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    • v.28 no.4
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    • pp.71-76
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    • 2009
  • Effects of dark adaptation have large safety implications. This study was aimed to investigate the effects of varying illuminance and the size of critical detail on visual performance (i.e., time-to-detect) in a dark room environment. While adapting to the dark environment, ten subjects were asked to detect and answer simple numerical expressions under 9 experimental conditions (3 illuminance level $\times$ 3 target size). The ANOVA results revealed that the time-to-detect was significantly affected by both of the illumination level and the size of critical detail. As illumination increased from 10 lux to 20 lux, the time-to-detect was significantly declined. For the size of critical detail, 0.5/min size (i.e., equal to 2 minutes of visual angle) resulted in a shorter time-to-detect, as compared to 0.7/min size (i.e., equal to 1.6 minutes of visual angle). Potential applications of this research include the development of design guidelines for illumination and warning signs in poorly illuminated viewing environments.

The Effects of Light and Dark Adaptation upon the Compound Eye of Nilaparvata lugens (벼멸구 겹눈의 명적응과 암적응 효과)

  • Young Nam Youn
    • Korean journal of applied entomology
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    • v.34 no.4
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    • pp.334-343
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    • 1995
  • The eyes of Nilaparvata lugens were examined for ultrastructural changes in the light and dark adapted states. Inspection of light microscope sections taken at similar levels of compound eyes from insects kept in light or darkness for periods up to 72 hors revealed some differences between light and dark adapted eyes. Using the electronmicroscope, in light adapted eyes the palisade layer was narrower than that in dark adapted eyes. The pigment granules still formed a ring around the palisade layer in the dark adapted eye but, they did not form a tight circle around the rhabdom. No constant difference was found between the diameters of the microvilli in light and dark adapted eyes. The pigment movements at the junction of the cone and the rhabdom took the effect on varying the pigment aperture at the tip of the cone in front of the rhabdom tip.

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A Study on the Convertible Emergency Lighting Fixture in Consideration of Dark Adaptation (암순응을 고려한 겸용형 비상조명등에 관한 연구)

  • Yum, Sung-Bae;Yoon, Cheol-Gu;Lee, Jung-Eun;Shin, Hye-Young;Song, Young-Joo
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.25 no.4
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    • pp.24-29
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    • 2011
  • When an emergency light turns on due to a blackout, the intensity of illumination is drastically changed from hundreds [1x] to 1.0[1x]. This sharp change of illumination intensity not only lowers the darkness adaptation of the eye, it also degrades the obstacle cognitive ability of the evacuees, resulting in secondary critical accidents due to anxiety, and fear. Thus, this study proposed a convertible emergency lighting fixture that controls the rate of speed of light in two stages by time with darkness adaptation of the eye in consideration. In addition, the effect of such emergency light is verified by suggesting an illumination simulation without increasing the number of light or capacity of battery to make it economically feasible.

Effects of Zinc and Its Chelators on ERG b-Wave Sensitivity During the Light Adaptation in Bullfrog Retina

  • Hwang, Kyung-Hee;Kim, Young-Hwal;Park, Jong-Seok
    • Korean Journal of Clinical Laboratory Science
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    • v.43 no.2
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    • pp.33-42
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    • 2011
  • Zinc plays a key role in genetic expression, cell division, and cell growth and is essential for the functions of more than 450 metalloenzyme. There are high concentrations of zinc in pigment epithelium in bullfrog eye. Zinc deficiency causes night blindness and abnormal dark adaptation. The purpose of this study was to identify ERG (electroretinogram) b-wave sensitivity during light and dark adaptation in bullfrog retina after zinc and zinc chelators treatment such as histidine and TSQ (N-(6-methoxy-8-qunolyl)-p-toluenesulfon amide). Especially, we focused whether histidine act as a zinc chelator in the Muller cell. The results of our study are summarized as follows: 1) Both zinc and histidine elevated ERG b-wave amplitude and threshold in Muller cells by accelerating rhodopsin regeneration time and increased a-peak absorbance during light adaptation. 2) TSQ reduced those by prolonging rhodopsin regeneration time and decrement of a-peak absorbance during light adaptation. 3) Zinc shortened rhodopsin regeneration time and prolonged a-peak absorbance. These results suggested that histidine may act as a zinc-mediated transporter in presynaptic Muller cell membrane rather than zinc chelator and acts as a GABA-receptor inhibitor which blocks $Cl^-$ influx to the postsynapse.

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The Combination Style Emergency Lighting Fixture which Considers a Dark Adaptation (암순응을 고려한 겸용형 비상조명등)

  • Yoon, Cheol-Gu;Choi, Hong-Kyoo;Lee, Guen-Moo;Kim, Young-Kyu;Kim, Jong-Soo;Chang, Min-Kee;Hwang, Sang-Gu
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2009.10a
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    • pp.145-148
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    • 2009
  • It is sharply decreasing from several hundred[lx] to 1.0[lx] when it turn on the emergency lamps. The sharply decreasing illuminance makes peoples to have dark adaptation for long time. And they were with fear and confused. It also causes secondary accidents by people who take a mistake. This paper studied the combination style emergency lighting fixture to improve a problem of dark adaptations. But it was made an assumption that same conditions of battery capacity and a number of emergency lamps.

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Effects of Light on Disassembly of Chloroplast during Senescence of Detached Leaves in Phaseolus vulgaris

  • Dong-Hee Lee;Jun
    • Journal of Environmental Science International
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    • v.1 no.2
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    • pp.69-80
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    • 1992
  • Effects of light on leaf senescence of Phseolus vulgaris were investigated by measuring the disassembly of chlorophyll-protein complexes in detached leaves which had been kept in the dark or under light. The loss of chlorophyll accompanied by degradation of chlorophyll- protein complexes. PSI (photosystem I) complex containing LHCI (light harvesting complex of PSI) apoproteins was rapidly decreased after the early stage of dark-induced senescence. RC(reaction center)-Cores was slightly increased until 4 d and slowly decreased thereafter. As disassembly of LHCII trimer progressed after the late stage of senescence, there was a steady increase in the relative amount of SC(small complex)-2 containing LHCII monomer. On the other hand, white and red light adaptation caused the structural stability of chlorophyll-protein complexes during dark-induced senescence. Particularly, red light was more effective in the retardation of LHCII breakdown than white light, whereas white light was slightly effect in protecting the disassembly of PSI complex compared to red light. These results suggest, therefore, that light may be a regulatory factor for stability of chlorophyll-protein complexes in the senescent leaves.

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THE NEW FINDING OF A LIGHT DEPENDENT $Ca^{2+}$ CHANNEL AND $Na^+-Ca^{2+}$ EXCHANGER IN THE VERTEBRATE RETINA (II)

  • Kim, Yun-Sook;Jung, Hyuk;Park, Chang-Suck;Woo, Suk-Hyang;Kim, Hyun-Jung;Kim, You-Young
    • Journal of Photoscience
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    • v.3 no.3
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    • pp.133-136
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    • 1996
  • Calcium modulates the activity of guanylate cyclase and plays a key role in dark and light adaptation in the visual system. We have measured the Ca$^{2+}$, K$^+$ and Na$^+$ concentration in dark and light adapted bullfrog's (Rana catesbeiana) vitreous humor by using the atomic absorption spectrophotometer. The calcium concentration of the light adapted bullfrog's vitreous humor was higher than that of the dark adapted bullfrog's vitreous humor. This means that ion activity between the photoreceptor and vitreous humor side is light dependent and we have found that a Ca$^{2+}$ channel and Na$^+$ - Ca$^{2+}$ exchanger exist in the vitreous humor.

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The Effect of Light and Darkness on Acclimatization of Laying Hens

  • Izzeldin, B.;Kassim, H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.5
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    • pp.694-697
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    • 2000
  • Laying hens kept in different light and dark periods of the day at high ambient temperature of maximum $35^{\circ}C$ were challenged to $38.5{\pm}0.5^{\circ}C$ acute heat 3 hours daily for 7 consecutive days. They were found to have a significant (p<0.01) acclimatization response (rectal temperature) to heat stress during the dark period compared to those exposed to the same temperature during the light period. The blood pH was not significantly different. The partial pressure of carbon dioxide ($PCO_2$) was significantly high (p<0.01) except in day 4. Similarly the blood bicarbonate ($HCO_3$) concentration was significantly high (p<0.05) except day three and day four. Acute heat exposure in the first day increased the body temperature in both groups (Light and Dark) reaching $44^{\circ}C$, followed by gradual reduction in body temperature. The dark treated birds showed rapid reduction in body temperature ($42.88^{\circ}C$) and adaptation to high temperature during days 2-4 but that this was lost to some extent in days 6-8. However this was not obvious in the light treated birds. It is concluded that darkness reduce hyperthermia and enhance acclimatization responses during acute heat stress.