• Korean Journal of Environmental Biology
• /
• v.22 no.1
• /
• pp.89-92
• /
• 2004

The effects of different light quality on the change of membrane potential difference (PD) of the guard cell in the intact leaf have been investigated. The mombrane PD was about -5.5 mV by white light of 600 $\mu$moles $m^{-2}\; s^{-1}$. The mean PD of change caused by red light was about -5.2 mV at the light intensity of 80 $\mu$moles $m^{-2}\; s^{-1}$. Membrane PD of guard cells in response to blue light was saturated at low light intensity. However, red and green light enhanced the change of membrane PD of guard cells with increasing intensity. In green light the biggest change of memrane PD was around -4 mV, whereas, with blue light the change of of memrane PD was around -2 mV. Accordingly, the membrane PD of guard cell showed the different degree of hyper-polarization by each wavelength.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.30 no.2
• /
• pp.78-85
• /
• 1994

The author carried out an experiment to find out the response of Striped puffer. Fugu xanthoperus (Temminck et Schlegel) to the color lights. The experimental tank (300L$\times$50W$\times$50Hcm) was set up in a dark room. Six longitudinal sections with 60cm intervals are marked in the tank to observe the location of the fish. Water depth in the tank was kept 50cm level. Light bulbs of 20W at the both ends of the tank projected the light horizontally into the tank. Two different colored filters were selected from four colors of red, blue, yellow, and white, and the were placed in front of the light bulbs to make different colors of light. Light intensity was controlled by use of auxiliary filiters intercepted between the bulb and the filter. The fishes were acclimatized in the dark for 60 minutes before they were employed in the experiment. Upon turning on the light, the number of fish in each section was counted 40 times in 30 second intervals, and the mean of the number of fish in each section was counted 40 times in 30 second intervals, and the mean of the number of fish in each section was given as the gathering rate of the fish. The colors favourited by the fish was found in order of blue, yellow, white and red in the daytime, and blue, white, yellow and red at night. The difference of the average distribution on two different colors of light was 13.12%(4.10-26.55%), and the difference in the daytime(14.79%) was larger than at night (11.45%). Constantly the gathering rate of fish on illumination period was fluctuated with instability. As the gathering rate of fish on illumination period was fluctuated with instability. As the gathering rate on one color of light increased, the gathering rate on the other color of light decreased. The difference of the gathering rate on two different colors of light was comparatively distinct and the difference in the daytime was larger than at night.

• Journal of the Institute of Convergence Signal Processing
• /
• v.14 no.4
• /
• pp.222-230
• /
• 2013

Retinal bipolar cells according to the light stimulus respond to potential slowly, emit neurotransmitter release(glutamine acid) to depend on membrane potential. In this paper, the several physiological information on neurotransmitter release mechanism in the presynaptic terminal of the ON-type bipolar cells are incorporated into the formula model. The source of fast components and slow components of neurotransmitter release was arranged in parallel, this model was able to reproduce the membrane potential and intracellular $Ca^{2+}$ concentration dependence of neurotransmitter release faithfully. In addition, because the fast releasable components of neurotransmitter was represented by the membrane potential dependence of trapezoid type, whereas the slow releasable components was represented by the membrane potential dependence of a bell type, $Ca^{2+}$ concentration rise in intracellular is suppressed by $Ca^{2+}$ buffer to reduce slow releasable components, it was confirmed that the membrane potential dependence of neurotransmitter release was characteristics of a trapezoid type. And, in the light response of ON type bipolar cell, the result of the simulation of the neurotransmitter release caused by the components of transient and persistent was that the start of light response occurred the fast release of neurotransmitter, it was confirmed that the transient component and persistent component of the light response occurred the slow release. It was confirmed that the later of persistent component of the light response occurred due to the continuous release by synaptic vesicle supplemented from the storage pool.

• The Korean Journal of Pharmacology
• /
• v.10 no.1 s.15
• /
• pp.11-19
• /
• 1974

To see if the treatments of d-amphetamine and chlorpromazine have any influence upon the orienting response and general behavioral activity, 3 groups of male Holtzman rats were prepared, namely d-amphetamine animals (1.0 mg/kg.i.p.), chlorpromazine rats (1.0 mg/kg.i.p.) and the physiological saline control animals. The general behavioral activity was examined by visual scanning using the time-sample method in the adaptation period of orienting response. The occurence of orienting response and its rate of habituation were evaluated by observing cessation of ongoing activity in response to a sound stimulus (1,000 Hz, 70 db & 0.1 sec), or turning of head toward the source of stimulus in 20 trials. Attention shift from sound to light stimulus was also tested in 10 trials. The results obtained were as follows; 1. The general behavioral activity of d-amphetamine group was significantly greater than that of control, however, the chlorpromazine animals showed the tendency to decrease in activity. 2. The d-amphetamine group showed the occurence of orienting response to sound significantly more often than that of placebo controls. However, the chlorpromazine group exhibited significantly fewer orienting response than the placebo group did. 3. The d-amphetamine group displayed no clear out habituation to the orienting response following the repetition of trials, though the placebo and the chlorpromazine groups demonstrated apparent habituation to the response. 4. The three animal groups did not differ significantly from each other with regard to shift of attention from sound to light stimulus. It is inferred that the d-amphetamine tends to increase general activity has a definite facilitative action of orienting response and a inhibitory influence upon the habituation of the latter response. On the contrary, the chlorpromazine tends to decrease general activity, has a inhibitory action of orienting response and facilitatory action of habituation of the response.

• Journal of Ginseng Research
• /
• v.41 no.3
• /
• pp.370-372
• /
• 2017

Three greenhouse experiments with American ginseng seedlings growing under light levels from 4.8% to 68% showed a quadratic response for root dry weight, giving an optimal root dry weight of 239 mg (range 160-415 mg) at an optimal light level of 35.6% (range 30.6-43.2%).

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.12 no.1
• /
• pp.115-122
• /
• 2012

In this paper, we demonstrate that indoor wireless optical communication is possible with lighting LEDs without a photo diode or a solar cell. A LED is used for both light emitting and light signal detection. This scheme is very useful because transmission is possible without any additional communication systems. In experiments, wireless optical communication will be carried out at a higher signal frequency of 5MHz using a lighting LEDs with both light emitting and light detection characteristics in the future.

• Journal of Forest and Environmental Science
• /
• v.33 no.2
• /
• pp.97-104
• /
• 2017

Investigation was carried out on response of Tetrapleura tetraptera (Schum. and Thonn.) to soil, water and light with the view of its domestication and introduction to different ecological regions. The experiment was arranged in a factorial experiment of $3{\times}3{\times}3$ in a completely randomized design (CRD) with three replicates. The factors were: soil textural class (Loamy sand, Sand and Sandy clay loam), watering regime (daily, twice a week and once a week) and light intensity (100%, 75% and 50%). Soil textural classes had significant influence on collar diameter, stem height, number of leaflets, root/shoot ratio and relative growth rate of Tetrapleura seedlings. Seedlings grown on loamy sand recorded the highest mean value- 2.28 mm for collar diameter, stem height- 12.9 cm, number of leaflets- 19.9, chlorophyll b- $0.34mg\;mL^{-1}$, leaf relative water content- 27.4% and relative growth rate- $0.037mg\;g^{-1}\;day^{-1}$. Watering regime had significant influence on the collar diameter of Tetrapleura. Seedlings watered daily recorded the highest mean value- 2.25 mm for collar diameter. Light intensity significantly influenced collar diameter and root/shoot ratio. Seedlings exposed to 100% light intensity recorded higher mean value for collar diameter- 2.28 mm and root/shoot ratio- 1.481 cm. The interaction between soil textural class and light intensity significantly affected collar diameter, stem height and number of leaflets. Higher mean value for collar diameter (2.47 mm) stem height (13.25 cm) and number of leaflets (21.16) were recorded while the interaction between soil textural class, light intensity and watering regime was significant for only number of leaflets. Tetrapleura exhibited some level of tolerance to different soil texture, drought and light intensity. Therefore, Tetrapleura has the potentials to be raised in different ecological zones characterized by difference in soil, rainfall and amount of sunshine.

• Journal of Photoscience
• /
• v.10 no.1
• /
• pp.157-164
• /
• 2003

Light exerts two primary roles in plant growth and development. Plants acquire all biochemical energy required for growth and propagation solely from light energy via photosynthesis. In addition, light serves as a medium through which plants recognize environmental fluctuations, such as photoperiod and presence of neighboring animals and plants. Plants therefore constantly monitor the direction, intensity, duration, and wavelength of environmental light and integrate these light signals into the intrinsic regulatory programs to achieve an optimized growth in a given light condition. Although light regulates all aspects of plant growth and developmental aspects, the molecular mechanisms and signaling cascades involved have not been well established until recently. However, recent advances in genetic tools and plant transformation techniques greatly facilitated the elucidation of molecular events in plant photomorphogenesis. This mini-review summarizes the gist of recent findings in deetiolation and suppression of shade avoidance response as classic examples of the phytochrome-mediated photomorphogenesis.

• Microbiology and Biotechnology Letters
• /
• v.22 no.2
• /
• pp.115-119
• /
• 1994

White mutant of Ganoderma lucidum(G4142) induced the non-basediocarpous basidiospores(NBB) from the aerial mycelia on agar media by the light illumination. Light was found to be necessary for NBB formation, but it also inhibited the growth of mycelium. The best sporulation was obtained at the periodic exposure of 16 hour light and 8 hour dark. Blue and yellow light were the most effective on sporulation, however, near UV and red light did not induce any spores. Effective light intensity for NBB bearing was about 1,000 lux as white light. Even after 16 days of culture, this strain did not form the pinhead nor chlamydospore. Optimum temperature for the mycelial growth and NBB formation were 30$\circ $C. Ganoderma lucidum G4142 exhibited the formation of stroma after five days of incubation at 30$\circ $C.

• Journal of Biomedical Engineering Research
• /
• v.17 no.2
• /
• pp.227-234
• /
• 1996

This paper is the study of the diffusion constant in order to calculate the percent oxygenation and percent blood volume using reflectance light within biological tissue. The diffusion constant play major role in percent oxygenation and percent blood volume and varies with the biological material such as hemolyzed blood, whole blood, dermis and epidermis in vivo tissue. The diffusion constant can be modeled to consist of a contribution from bloodless tissue and blood present in tissue. The reflectance light for experimental are red light of 660nm, infrared light of 880nm, green light of 569nm. The correlation between the diffusion constant and biological tissue was analyzed by the intensity of reflectance light at different depth within human limb. The reflectance light was changed in response to physiological changes within biological tissue. The data for diffusion constant were obtained at different depth beneath the surface of the skin and will be utilized to amen the percent oxygenation and percent blood volume.