• Title/Summary/Keyword: darkness

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Effect of dark incubation in germination of indirect date palm somatic embryos and conversion into plantlets

  • Mansour Abohatem;Yousra Al-Qubati;Hanan Abohatem
    • Journal of Plant Biotechnology
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    • v.50
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    • pp.267-274
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    • 2023
  • All studies on date palm somatic embryogenesis have focused on germination in the presence of light while neglecting germination in darkness, which mimics the germination process of zygotic embryos within seeds. To improve the date palm micropropagation protocol, we investigated the effects of light and darkness incubation on the germination of indirect date palm somatic embryos and their subsequent conversion into plantlets. Darkness incubation emerged as a pivotal factor in the germination of indirect date palm somatic embryos and their successful conversion into plantlets. Darkness incubation significantly decreased the time required for the conversion of indirect somatic embryos into plantlets, halving the duration from 24 weeks to only 12 weeks. The micropropagation protocol was modified, consolidating the previous two distinct stages of germination and elongation under light incubation into a single stage under darkness incubation. These findings modified the protocol and significantly reduced the overall duration of the date palm micropropagation protocol.

The Conversion of Narrative Strategy: from "An Outpost of Progress" to Heart of Darkness (서술 전략의 전환-「진보의 전초기지」에서 『어둠의 핵심』으로)

  • Lee, Man Sik
    • Journal of English Language & Literature
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    • v.57 no.4
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    • pp.625-649
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    • 2011
  • Even though "An Outpost of Progress" and Heart of Darkness were based upon Joseph Conrad the sailor's same experience in Congo Free State, their narrative strategies are quite different. The realistic representation of "An Outpost of Progress," with which Conrad was not satisfied at all, was converted into the modernistic narrative strategy of Heart of Darkness so that the sympathetic power of the story should be improved. The conservative value system of realism is expressed by the omniscient author in "An Outpost of Progress," whereas the frame narrator of Heart of Darkness is proved to be an unreliable one whose norms and behavior are not in accordance with the implied author. The glorious history of the British Empire, which was proudly presented by the frame narrator at the beginning of Heart of Darkness, was strongly opposed by Marlow, another narrator, who said that the British Empire had been "one of the dark places of the earth" when ruled by the Roman Empire. The feeling of the frame narrator was uneasily changed into the gloomy mood when he described the Thames as the flow which "seemed to lead into the heart of an immense darkness" at the end of Heart of Darkness. Similar to the straightforward narrative strategy of representation in "An Outpost of Progress," the realistic approach of Part I in Heart of Darkness is considered by Conrad as insufficient to reveal the darkest truth of imperialism, which was declared by Kurtz as "The Horror! The Horror!" Thus Conrad uses the Chinese-box structure, in which Kurtz' episode is enveloped by Marlow's tale which is enclosed by the frame narrator's story, in order to penetrate into the mind of ordinary readers in the novelist's age of New Colonialism, while attacking the ideology itself of imperialism instead of critisizing its inefficiency and individualism.

Effect of Alteration of Light-Darkness Cycle on Nitrogen Retention in the Rat (주야 변경이 흰쥐의 체내 질소 보유에 미치는 영향)

  • Kim, Mi-Kyung
    • Journal of Nutrition and Health
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    • v.16 no.4
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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.

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A Study on Cognition and Perception of Space through Contrast and Integration of Light and Darkness (빛과 어둠의 대비와 통합에 나타난 공간의 지각과 인식에 관한 연구)

  • Kim, Jong-Jin
    • Korean Institute of Interior Design Journal
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    • v.19 no.5
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    • pp.3-10
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    • 2010
  • In the history of art and architecture, there are different characteristics in relationship between light and space. Among them, two characteristics seem to be fundamental : The first is that contrast between light and darkness is more articulated. Direct sunlight penetrates into the dark interior space made by heavy masonry structure. This is generally found in the traditional western religious buildings. The second is that light is mixed with darkness and becomes shade. Shade is different from shadow that is usually perceived as the opposite of light. Sunlight is filtered under through the big horizontal roof and rice paper walls in the traditional far-east Asian architecture and becomes weak ambient light. In this shade, there is no strong contrast between light and darkness. This difference is not only originated from the architectural differences, but also originated from the conceptual differences about light, space, and the world in two cultures. This paper tries to study the philosophical, aesthetical backgrounds as well as case examples in art and architecture of two characteristics. Based on the case studies, this paper aims to analyze the main perceptual structure. Finding the relationship between light, space, and human body by making three dimensional models is the crucial analysis method of this research. Although in real life and experiencing the world, these two characteristics are not clearly separated, comparative study based on different cultures gives opportunity to think of diverse perspectives on light and space.

Roland Giguère and Poetic Landscape - La main au feu (롤랑 지게르와 시의 풍경 - 『불 위의 손』을 중심으로)

  • Kim, Yong Hyun
    • Cross-Cultural Studies
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    • v.39
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    • pp.153-176
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    • 2015
  • Poet, painter and publisher, Roland $Gigu{\grave{e}}re$ is one of Quebec's outstanding figures, inspired by both Surrealism and Quebec nationalism. He participated in contemporary artistic movement 'Phases' and influenced collective self-awareness and political ferment, 'Quiet Revolution'. In La Main au feu(1973), his poetry represent a landscape dominated by darkness in contrast with red color of fire from the volcanic crater. The world is immersed in darkness of despair which allude to the Great Darkness of Quebec society. Acts of violence assume many different forms: crows, black rain, dark flow, frenzy of knife blows. Both things and humans are in the state of absence or lack. Life falls into opacity of death. In the background of dark landscape, we discover Miror, a singular character. Similar to chain of mountains and to bare forest, he is a creature that shape the tragic inner world of poet. He is as like as seismograph that record the tremble of being. Finally, in order to fight the darkness of environment, the poet attempt to use the power of fire of volcanoes. The flow of magma become paintings of his dream and the flame of eruption, poetry of cry toward the sky. 'La main au feu' means the will to resist injustice and repression in the world. The tragic reality is replaced by a dream that become second reality out of reach of the force of hostile external circumstances.

Mothers' Experiences of Caring for Visually Impaired Children (시각장애 아동을 위한 어머니의 돌봄 경험)

  • Oh, Sangeun
    • Child Health Nursing Research
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    • v.23 no.2
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    • pp.219-228
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    • 2017
  • Purpose: The purpose of this study was to understand and explore the essences of Korean mothers' experiences of caring for visually impaired children. Methods: Data were collected through individual in-depth interviews using open-ended questions. Five mothers of children with visual impairments participated in the interviews. Verbatim transcripts were analyzed using phenomenological analysis. Results: Analysis with Colaizzi's method showed two categories which included 14 themes in 4 theme clusters. The first category was 'surviving in the dark reality' included 2 theme clusters, of 'outcrying in the darkness' and 'enduring the darkness while caring for my child alone'. The second category was 'living as the light of maternal affection' including 2 theme clusters of 'preparing the light to shine in the darkness' and 'going through the darkness with the lights of love'. Conclusion: The findings from this study provide deep understanding of mothers' experiences of caring for visually impaired children. Based on the results of the study, health professionals can develop effective family nursing interventions to improve the quality of life for these families including the visually impaired children and their mothers.

Effect of Light on Mycelial Growth, Pigmentation and Sclerotial Production of Corticium sasakii (shirai) Matsumoto (문고병균(Corticium sasakii)의 균사생장, 색소형성 및 균핵형성에 미치는 광선의 영향)

  • Yu, Seung Hun;Park, Jong Seong
    • Korean Journal of Agricultural Science
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    • v.2 no.2
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    • pp.375-380
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    • 1975
  • Effects of light on mycelial growth. pigmentation and sclerotial production of Corticium sasakii were investigated on rice polish agar at $29^{\circ}C=1$. 1) In both isolates. D-3 and D-15. light had no affect on the mycelial growth of C. sasakii. Isolate D-15 did not produce a brown pigment within its mycelium and culture medium in all treatments. but isolate D-3 were more intensively pigmented in light than in darkness. 2) Effect of light on sclerotial production of C. sasakii was different between two isolates. Isolate D-3 produced the most sclerotia in constant light, intermediate in alternating light and darkness and the least in constant darkness. 3) Isolate D-15 produced a little more sclerotia in light than in darkness, but the differences were not statistically significant. However, this isolate produced a larger number of big sclerotia in constant darkness than in constant light and in alternating light and darkness.

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Quality Comparisons of Tomatoes Irradiated with Light, Treated with Ethylene, and Stored in Darkness

  • Lee, Gwi Hyun;Bunn, Joe M.;Han, Young J.
    • Agricultural and Biosystems Engineering
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    • v.1 no.2
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    • pp.81-87
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    • 2000
  • Quality characteristics of tomatoes irradiated with light (red light of far-red light followed two days later with a red light treatment), treated with ethylene, and stored in darkness were evaluated by subjective sensory and objective physical and chemical evaluations. Overall and individual liking evaluations and sensory evaluations were made by an untrained panel of eighteen people. A rankin gof treatments for consumer (panelist) acceptability was also conducted by the panel. Physical and chemical evaluations included surface color measurement (L*, a*, and b*), mechanical puncturing (firmness), soluble solids content (SSC), titratable acidity(TA), and tomato juice pH. Sensory data showed that outside color, inside color, and flavor of tomatoes treated with red light (R) and far-red light/red light (FR/R) were scored significantly higher than those of tomatoes treated with ethylene and those kept in darkness. The L* values for tomatoes treated with R and FR/R were lower (more darkening) than those for tomatoes treated with ethylene and those stored in darkness. Tomatoes treated with FR/R had the highest A* values, followed by those irradiated with R, treated with ethylene, and kept in darkness, respectively. Sensory values for firmness were similar for tomatoes treated with R, FR/R, and ethylene. Treatments had no significantly different effects on sweetness and acidity. There were no significantly different effects between treatments for pH, SSC, TA, and SSC/TA. From observations made during the study, it was suggested that R irradiation stimulated red color development in tomatoes after it had been delayed by FR irradiation. Consumer acceptability for tomatoes with either R or FR/R treatment was significantly higher than that for tomatoes treated with ethylene or stored in darkness. panelists' overall liking scores correlated well with all sensory variables except acidity, and also correlated highly with inside color, flavor, and sweetness (P<0.001). Overall liking versus flavor had the most pronounced relationship (r=0.78, P<0.001).

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Effect of light on conidial formation in several anthracnose fungi (몇가지 탄저병균의 분생포자형성에 미치는 광선의 영향)

  • Chung H. S.
    • Korean journal of applied entomology
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    • v.7
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    • pp.57-59
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    • 1969
  • Effect of light on conidial formation of Colletotrichum panacicola, C. gloeosporioides, C. runcatum and C. nicotianae was examined on potato dextrose agar on which each conidial suspension was seeded. The light source was Mitsubishi day light fluorescent lamps wi th an intensity of 100-120 ft-c at the colony surface. The treatments were (i)constant light, (ii) constant darkness, and (iii) alternating light (11hr.) and darkness {13hr.) at $26\{\circ}C\pm2$. With the exception of C. nicotianae, constant light gave the greatest sporulation over that obtained in the other two treatments; there were on significant differences in number of sporulation between under constant darkness and alternating light and darkness. C. nicotianae resulted in maximum. inter mediate and minimum sporulation under alternating light and darkness. constant darkness and constant light, respectively. These differences were statistically significant at $5\%$ level. C. truncatum and C. nicotianae produced abundant conidia in the entire test; C. gloeosporioides was intermediate, and C. panacicola was the least. Differences in number of sporulation due to light. organisms. and t he interaction of these two were all statistically significant.

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Mechanism of the Cucumber Cotyledon Greening Induced by KC6361 in Darkness (암조건에서 오이자엽의 녹화를 유기시키는 KC-6361 화합물의 작용기구)

  • Kim, J.S.;Kim, T.J.;Cho, K.Y.
    • Korean Journal of Weed Science
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    • v.14 no.3
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    • pp.176-183
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    • 1994
  • This study was conducted to investigate how KC6361, a new type diphenylether compound inducing bleaching, increase the greening of cucumber cotyledon in darkness. Protoporphyrin IX formation, reaccumulation rate of protochlorophyllide(Pchlide) in darkness after phototransformation and Shibata shift were not affected. Whereas, aminolevulinic acid(ALA), protochlorophyll and chlorophyll were increased, and especially protochlorophyll was significantly accumulated. When KC6361 and phytol were applied alone or in combination with ALA, the transformation from Pchlide into protochlorophyll was accelerated in darkness. These results suggest that the greening of the etiolated cucumber cotyledon treated with KC6361 seems to be caused by the accumulation of phytol or/and Geranylgeranylpyrophosphate and their increased esterification with Pchlide in darkness.

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