• Journal of Photoscience
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• v.5 no.1
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• pp.17-22
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• 1998

Changes of chlorophyll fluorescence and xanthophyll cycle pigment contents in maize leaves were investigated dunng desiccation in darkness or in the light. In darkness, a drastic dehydration of detached maize leaves down to 50% relative water content (RWC) affected photochemical efficiency of photosystem II (Fv/Fm) and pht)tochemical quenching (qP) only slightly. In contrast, desiccation in the light with a moderate intensity led to a pronounced reduction in Fv/Fm with a Fo quenching when RWC was greater than 70%. This reduction in Fv/Fm could be recovered in darkness under hutrod condition. In leaves with RWC below 70%, significant reduction in Fv/Fm was accompanied by an increase of Fo, which could not be reversed within 5 h in darkness under humid condition. The nonphotochemical quenching increased during desiccation in the light with a concomitant rise in zeaxanthin at the expense of violaxanthin. Pretreatment with dithiothreitol (DTT), an inhibitor of zeaxanthin synthesis, inhibited the development of nonphotochemical quenching and prevented the xanthophyll interconversion during desiccation in the light. These results suggest that even light with a moderate intensity becomes excessive under dehydration and zeaxanthin-associated photoprotection of photosynthetic apparatus against photodamage is involved, but the protection is not complete against severe desiccation.

• Journal of People, Plants, and Environment
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• v.24 no.6
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• pp.639-649
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• 2021

Background and objective: Various images from visual display terminals (VDTs) as well as living lighting are important parts of our daily life; thus, properly controlling the lighting environment - that is, illuminance, color temperature and good images from VDTs - can have a substantial effect on improving the mental health and work efficiency in everyday life. We examined electroencephalography (EEG) and heart rate variability (HRV) responses to various lighting conditions in 25 university students as they viewed images of a green landscape or traffic congestion. Methods: EEG was performed in darkness and when the room was illuminated with 10 different light-emitting diode (LED) color temperatures, while the EEG and HRV responses to green landscape or traffic congestion image stimuli were measured in darkness and during room illumination with three different LED color temperatures. Results: We found a significant difference between darkness and high LED illumination (400 lx) at 7 (CZ, F4, FZ, O1, O2, OZ, and T6) of 30 channels, while the alpha wave activity increased during darkness. In the second experiment, the green landscape image stimuli in the 30 lx-2600 K lighting condition elicited theta wave activity on the EEG, whereas the traffic congestion image stimuli under high LED illumination elicited high beta and gamma wave activities. Moreover, the subjects exhibited better stress coping ability and heart rate stability in response to green landscape image stimuli under illuminated conditions, according to their HRV. Conclusion: These results suggest that lower color temperatures and illumination levels alleviate tension, and that viewing green landscape image stimuli at low illumination, or in darkness, is effective for reducing stress. Conversely, high illumination levels and color temperatures are likely to increase tension and stress in response to traffic congestion image stimuli.

• The Journal of the Korea Contents Association
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• v.7 no.9
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• pp.18-25
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• 2007

A symbol is one of the images that represents individual elements, and it has the power of metaphoric delivery to its audiences. Symbols, in animation, allows the audience to perceive various descriptions as symbols, leading to variety of interpretation. And by providing psychologically deeper meaning to the audience, it enhances the symbolic value of the images. However, detailed study regarding symbol analysis leaves much to be desired. This paper is an semiological approach to the Czechoslovakia animator, Jiri Barta, and his symbolic images, with particular focus on the darkness symbols that appear in the Czech cultural characteristics.

• Journal of English Language & Literature
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• v.64 no.3
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• pp.415-432
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• 2018

This essay reinterprets Joseph Conrad's The Heart of Darkness as satirical writing. In an experience-based fictional world, Conrad places imperial precursors who present themselves with a derogatory demeanor that stems from corrupt rapacity at its forefront. This rapacity is enabled by what European colonists believe to be a noble cause, regarded as a vehicle with which to enlighten African continent in his work. This essay reads this noble cause that allows such exorbitant and corrupt rapacity as a dominant element in the construction of Conrad's characters, particularly Kurtz, as objects of satire. Kurtz ends up beginning his calamitous descent into barbarism, mockingly quite opposite to what the colonial disciples misconceive themselves to be. In exhuming the satirical elements from the novel, this paper proves the significance of reading The Heart of Darkness as satire as an alternative reading to the racist book Chinua Achebe has accused it of.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.2
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• pp.51-55
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• 1979

The effects of vernalization and darkness on flower initiation were reviewed by using naked barley varieties. The dark effects were pronounced on flower induction even at 25$^{\circ}C$. There were no differences in flowering responses among varieties. The effects of vernalization and darkness combined with 25$^{\circ}C$were 100% and 60% respectively which showed a significant difference. When the alternation of darkness with light was taken as first and last the flowering rate was 92 percent. When it was intercalated by light treatments the flowering rate was 91 per cent. Thus the effects of vernalization and darkness seems to differ.

• Molecules and Cells
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• v.43 no.7
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• pp.645-661
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• 2020

Leaf senescence is a developmental process by which a plant actively remobilizes nutrients from aged and photosynthetically inefficient leaves to young growing ones by disassembling organelles and degrading macromolecules. Senescence is accelerated by age and environmental stresses such as prolonged darkness. Phytochrome B (phyB) inhibits leaf senescence by inhibiting phytochrome-interacting factor 4 (PIF4) and PIF5 in prolonged darkness. However, it remains unknown whether phyB mediates the temperature signal that regulates leaf senescence. We found the light-activated form of phyB (Pfr) remains active at least four days after a transfer to darkness at 20℃ but is inactivated more rapidly at 28℃. This faster inactivation of Pfr further increases PIF4 protein levels at the higher ambient temperature. In addition, PIF4 mRNA levels rise faster after the transfer to darkness at high ambient temperature via a mechanism that depends on ELF3 but not phyB. Increased PIF4 protein then binds to the ORE1 promoter and activates its expression together with ABA and ethylene signaling, accelerating leaf senescence at high ambient temperature. Our results support a role for the phy-PIF signaling module in integrating not only light signaling but also temperature signaling in the regulation of leaf senescence.

• Korean journal of applied entomology
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• v.14 no.4 s.25
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• pp.205-208
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• 1975

Effect of light and temperature on the sporulation and mycelial growth by 4 strains of Mycosphaerella fragariae was examined. The light source was day light fluorescent lamps with an intensity of 2000 Lux at the colony surface. The treatment were constant light, alternating light(10hr) and darness (14h.) and constant darkness af $15^{\circ}C,\; 22^{\circ}C\; and\; 30^{\circ}C$ 1. Of the 4 strains tested, alternating light and darkness at $22^{\circ}C\;and\;15^{\circ}C$ gave the greatest sroducedtion, constant light in intermediate, constant darkness in minimum, but darkness at $30^{\circ}C$ produced abundant conidia over that obtained in the other two treatment. Differences in number of sporulation due to light, strains and the interaction of these two were all statistically significant. 2. There were not on significant differences in amount of mycelial growth due to light, but amount of mycelial growth of$S_3$ strain were the nest abundant among the 4 strains.

• Journal of English Language & Literature
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• v.55 no.1
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• pp.61-82
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• 2009

This paper aims to reexamine the issue of racism in Conrad's Heart of Darkness, especially in the light of Chinua Achebe's critique of the novella as a racist text entrenched with European prejudices of Africa and its people in his 1975 speech at the University of Massachusetts titled "An Image of Africa." While the novella's indictment of imperial exploitation has been noted from an early stage of its critical reception, its racism had hardly been discussed until Chinua Achebe posed it. Achebe offers the canonized status of the text as a modernist classic, "the most commonly prescribed novel in twentieth-century literature courses," as one reason for its obvious manifestations of racism being glossed over. One may add that Conrad's militant denunciation of imperialist enterprises as "a sordid farce," his seemingly radical stance against imperialism, serves as ideological constraints upon his readers, blinding them to its immanent racism. A closer look at the novella's attack on imperialism turns out to be contradictory, for it also shows such liberal-humanist ideas as the civilizing mission, the work ethic, and the superiority of civilized man, all of which served to prop up European imperialism at the end of the nineteenth century. This ideological contradiction also accounts for Conrad's racist attitude, which is betrayed in his portrayal of Africans as obscure, primitive. Euro-American imperialism has frequently justified itself by recourse to racism, but racism has not always been allied with imperialism. Some staunch racists such as Robert Knox and Arthur de Gobineau went against imperialism, and Conrad proves one of such cases whose critique of imperialism is voiced in ways that can be characterized as racist.

• Journal of the Korean Professional Engineers Association
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• v.18 no.2
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• pp.16-22
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• 1985

This study was carried out to evaluate the quality of soybean sprouts grown under three different sources of light. The soybean was germinated under light through blue (251 ux), red (751 ux) and white (50 to 200 lux) polyethylene films at 25$^{\circ}C$ for 10hr./day. Vitamin C, chlorophyll, cellulose and total protein contents were determined and texture was evaluated by tasting soybean sprouts soup. protein pattern in the soybean sprouts were investigated using polyacrylamide gel electrophoresis. Vitamin C, chlorophyll and cellulose contents were increased by white light intensity. The texture of the sprouts grown under white light (50 lux, 100 lux) was better than darkness, but fought under 200 lux. Vitamin C contents of soybean sprouts grown under various sources of light (in order of light : blue > white > red) were higher than theses of ones grown in the darkness. Biosynthesis of chlorophyll was not correlated to Vitamin C content. Total protein contents of cotyledon was not changed significantly under light irradiation. But the soybean sprouts grown under different quality of light, hypocotyl was higher than those grown darkness. (37% and 20% higher for blue light and white light) Densitometric tracing of disc polyacrylamide gel electrophoretic patterns showed that protein of hypocotyl under white light had more high molecular weight protein.

• 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.