• Title/Summary/Keyword: dark adaptation

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

  • Lee Dong-Hee;Hong Jung-Hee;Kim Young-Sang
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.1 no.2
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    • pp.69-80
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    • 1997
  • Effects of light on leaf senescence of Phaseolus 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)-Core3 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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Studies on Visual Function Measurements for Building Visual Function Database of the Elderly (고령자의 시각기능데이터베이스 구축을 위한 시각기능계측에 관한 연구)

  • Kim, Dong-Wook;Park, Kwang-Suk;Kim, Jung-Ja;Kim, Nam-Gyun
    • Journal of Biomedical Engineering Research
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    • v.28 no.5
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    • pp.618-627
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    • 2007
  • As our society progresses rapidly toward an aged society, there is a stiff increase in the population of the aged persons who have difficulties in adjusting themselves to environments due to declines of their physical functions. Therefore, there is a great need for the concept of 'Universal Design' that demands the design of overall social structure to care for the elderly. Due to this reason, the physical function of the aged persons should thoroughly be studied for the development of rehabilitation and training equipments to help the recovery of physical functions of the elderly. Among the variety of physical functions of the elderly, visual functions, motion characteristics, hearing functions, and somatosensory functions have significant influence toward everyday lives and are physical functions to study for the construction of urgently needed physical function databases of the elderly. This study concentrates on visual functions among the variety of physical functions of the elderly. To measure various visual functions of the elderly, a measurement room for the elderly has been developed, which can mimic everyday lives and perform measurements of visual functions with subjects in seated position. The measurement items for the construction of the database were capabilities in everyday vision according to changes in arrangement of colors and light intensity and capabilities in everyday vision, color distinction, dark adaptation, and light glare against changes in contrast.

Evolutionary Study on the Dark Chub (Zacco temmincki) 1. Geographic Distribution and Seasonal Variation of Two Allelomorphs of MDH (갈겨니(Zacco temmincki)의 진화에 관한 연구 1. MDH 동위효소 2형의 지리적 분포 및 계절적 변이)

  • 양서영;민미숙
    • The Korean Journal of Zoology
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    • v.32 no.3
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    • pp.232-241
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    • 1989
  • Two cytosol malate dehydrogenase allelomorphs are found in the Dark Chub, Zacco temmincki, a freshwater fish inhabiting Korean waters. Mdh-1MM(hereafter referred to as A-type) is distributed along the south and southeastern parts of Korea, whereas the B-type(Mdh-1MS) is found everywhere except the southeast. Several syrnpatric populations can be found in the southern areas with no hybridization between them. The pattern of geographic distribution would indicate that A-type is superior adaptation to colder water temperature; this is collaborated by evidence collected from a sympatric length of the Tongchon stream, Namhae. The relative warmth of the water along this portion of the stream's length was determined its altitude and the time of year. Frequency of B-types found was directly proportional to the relative warmth of the water and inversely proportional to the nurnber of A-types found in the sarne station. Current data tends to suggest that the B-type of Zacco temrnincki first differentiated from Zacco platypus approximately one million years ago (Yang et al., 1984) while A-type subsequently branched from B-type 300,000 years later(Yang and Mm, 1987) through a progressive adaptation toward colder temperature.

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Analysis of Korean Dietary Life Adaptation of Married Female Immigrants (결혼이주여성의 한국음식문화 적응 경험 분석)

  • Lee, Jeong-Sook
    • Korean Journal of Community Nutrition
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    • v.22 no.2
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    • pp.103-114
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    • 2017
  • Objectives: This study aims to investigate the married female immigrants' experience on Korean dietary life adaptation, especially identifying the symbolic meaning and nature of experiences. Methods: This study was conducted with six married female immigrants through an analysis of the qualitative materials which consisted of in-depth interviews, field notes and materials. Data was analyzed using Giorgi's phenomenological research methods. Results: The results were deduced as 116 significant statements, 17 formulated meanings (sub-theme), and 6 theme clusters. Six theme clusters comprised of lack of preliminary knowledge and information, conflict and support in relationships, Korean food culture which is different from homeland, adaptation attitudes of Korean food culture according to situation, sharing of homeland food culture, and practical difficulty and expectative service. The participants started Korean life in the dark about Korea and Korean food culture, so they were subjected to trial and error. The conflict between Korean mother-in-law and foreign daughter-in-law came from lack of consideration of daughter-in-law's cultural background. Some participants were hurt because of misunderstanding and nitpicking. They were learning about cooking method, ingredient, seasoning, table setting and manner. Some participants integrated Korean food culture and their homeland food culture. Some of them assimilated with Korean food culture. One of them maintained homeland food culture. The participants who adapted Korean food culture well could share homeland food amicably. They sometimes didn't apply the services which were offered by the government, because the services did not fit their needs. Some of them didn't know the usage route of the services or information. They had resistance about home teaching and it showed that outreach service was not always effective. Conclusions: This study suggested that it is necessary to develop a practical support plan which covers married female immigrants' real needs and system improvement measures.

VENGEANCE, VIOLENCE, VAMPIRES: Dark Humour in the Films of Park Chan-wook

  • Hughes, Jessica
    • Cross-Cultural Studies
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    • v.28
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    • pp.17-36
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    • 2012
  • This essay places the South Korean film Thirst (2009) within Park Chan-wook's oeuvre as a filmmaker notorious for graphic depictions of violence and revenge. Park's use of dark humour in his films, which is emphasized in Thirst perhaps more than ever, allows for a more self-aware depiction of violence, where both the viewer and the protagonist are awakened to the futility of revenge. This ultimately paints his characters as fascinatingly crazy - simultaneously heroes, villains, and victims. Film theorist Wes D. Gehring's three themes of dark humour ('man as beast,' 'the absurdity of the world,' and 'the omnipresence of death') become most obvious in Park's most recent film, which pays closer attention to character development through narrative detail. Rather than portraying the characters as sentimental, dark humour depicts their misfortunes in an alternative way, allowing for consideration of such taboo subjects as religion, adultery, and death/suicide. These issues are further tackled through Thirst's portrayal of its vampire protagonist, which ultimately de-mystifies the traditional vampire figure. While this character has more often been associated with romance, exoticism and the mystical powers of the supernatural, Thirst takes relatively little from the demons of Nosferatu (Murnau, 1922) and various other Dracula adaptations, nor the romantic figures of Interview with the Vampire (Jordan, 1994), and Twilight (Hardwicke, 2008). Instead, it is part of a much smaller group of contemporary vampire films, which are rather informed by a postmodern reconfiguration of the monster. Thus, this paper examines Thirst as an important contribution to the global and hybrid nature of those films in which postmodern vampires are sympathetic and de-mystified, exhibiting symptoms stemming from a natural illness or misfortune. Park's undertaking of a vampire film allows for a complex balance between narrative and visuals through his focus on the Western implications of this myth within Korean cinema. This combination of international references and traditional Korean culture marks it as highly conscious of New Korean Cinema's focus on globalization. With Thirst, Park successfully unites familiar images of the vampire hunting and feeding, with more stylistically distinct, grotesque images of violence and revenge. In this sense, dark humour highlights the less charming aspects of the vampire struggling to survive, most effective in scenes depicting the protagonist feeding from his friend's IV in the hospital, and sitting in the sunlight, slowly turning to ash, in the final minutes of the film. The international appeal of Park's style, combining conventions of the horror/thriller genre with his own mixture of dark humour and non-linear narrative, is epitomized in Thirst, which underscores South Korea's growing global interest with its overt international framework. Furthermore, he portrayal of the vampire as a sympathetic figure allows for a shift away from the conventional focus on myth and the exotic, toward a renewed construction of the vampire in terms of its contribution to generic hybridization and cultural adaptation.

Studies on the Influence of Nicotinamide and Folic Acid on the Regeneration of Rhodopsin (Rhodopsin 의 再生에 對한 Nicotinamide 와 Folic Acid 의 影響에 關한 硏究)

  • Kang, Seoung-Ho;Choi, Tae-Joo
    • Journal of the Korean Chemical Society
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    • v.6 no.1
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    • pp.32-35
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    • 1962
  • Six frogs (Rana nigromaculata 25∼40 gm) were adapted to light for 2 hours. Then 0.02 ml of 3% nicotinamide and 0.02 ml of 0.6% folic acid were injected into the vitreous body of the right eye-ball, and 0.02 ml normal saline solution into the vitreous body of the left eye-ball respectively. After dark adaptation for an hour-their heads were cut off under a dim red light (650 $m{\mu}$). The retinae were removed from the left eye-ball for the control group and from the right for the test group respectively. Then rhodopsin was extracted from the retinae with 3 ml of 2% digitonin solution(pH = 7.0) for 17 hours at 0$^{\circ}C$ in the dark. The optical densities before and after the illumination of the extract were measured and compared with those of the control group. The results are as follows: 1) The group which had been injected with 0.02 ml of 3% nicotinamide solution had the promotive action on tile regeneration of rhodopsin in comparison with the control group. 2) The group which had been injected with 0.02 ml of 0.6% folic acid solution had the controlling action on the regeneration of rhodopsin in comparison with the control group.

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Study on the colors of Kim Whan-ki's painting (색으로 본 김환기의 작품 세계)

  • Kim, Hyun-Suk
    • The Journal of Art Theory & Practice
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    • no.3
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    • pp.155-172
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    • 2005
  • Kim Whan-ki is an unusual instance in Korean modern artists, who payed attention to emotional and expressive effects of colors. The color of Whan-ki's paintings have been recognized as linked with 'blue' in spite that he used colors within the category of 'Colors of Five Directions(五方色)', which are traditional oriental colors composed of red, lue, yellow, white, green and black. Kim Whan-ki unearthed upon similarity of Five Directions Colors to the three(five) primary colors which modern abstract painter like Mondrian layed down. Whan-ki switched the five directions colors to modern ones. Kim Whan-ki's dot painting in which pure and watery color is sucked in ground is modernistic adaptation from ink painting. He packs a dot with sky and earth, moon and stars, forest and tree, birds and flowers, friends at his hometown, wind, sound and so on. Putting tens of thousands of these shapes and colors into a dot is modernistic version from ink painting. In that point there is a possibility to say that 'dark blue' of the dot painting is 'Hyun-saec(玄色)'. Eventually we can make sure that Kim Whan-ki's view of Art originated in oriental philosophy and beauty.

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CALCIUM EFFECTS OF VISUAL ADAPTATION IN A VERTEBRATE RETINA (I)

  • ung, Hyuk J
    • Journal of Photoscience
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    • v.3 no.3
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    • pp.127-132
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    • 1996
  • Calcium has a variety of functions in neuron and muscle cells and blood clotting, especially in the visual system where dark adapted rods cotransport with Na$^+$ into the cell. An influx of Ca$^{2+}$ flows out of the cell through the Na$^+$ - Ca$^{2+}$ exchanger. By using a modified Ussing chamber in order to bring in vivo environment close, we have concluded that Ca$^{2+}$ blocks the activity of guanylate cyclase; in consequence, having an effect on the amplitude of electroretinogram (ERG). We suggest that Ca$^{2+}$ moves between the photoreceptor and the vitreous humor by way of certain Ca$^{2+}$ transport mechanisms. Also, the effect of Zn$^{2+}$ in Ca$^{2+}$ - free ringer solution caused an elevation of amplitude in ERG and a reduction of threshold.

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The Effect of Changing Driving Brightness on Older Drivers

  • Jeon, Yong-Wook;Shin, Sung-Heon
    • Journal of the Ergonomics Society of Korea
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    • v.29 no.4
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    • pp.619-624
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    • 2010
  • The traffic accidents of the aged are increasing because old people generally experience a decline of physical functions and judgment but their dependence on automobiles increases. In order to investigate the older drivers' response to traffic signs and surrounding environment according to changing driving brightness, this study measured the visual cognitive behavior, driving behavior, and subjective evaluation while the driving brightness was changed using a driving simulator. Furthermore, the drivers who recognized traffic signs and those who did not were compared. As a result, it was found that some older drivers had declined ability of cognition, some failed to adapt to rapid brightness change even if sufficient attention was given to traffic sign, and some could not safely control the vehicle when approaching intersections. Therefore, the development of support systems for aged drivers in traffic environment is necessary in the future.

Brightness Function on TV Viewing Condition (TV 시청 조건에서의 Brightness Function)

  • 최성호;김희철;장수욱;김은수;한찬호;송규익
    • Proceedings of the IEEK Conference
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    • 2003.07e
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    • pp.2403-2406
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    • 2003
  • When viewing images, the relative luminance of the surround has a profound impact on the apparent contrast of the image. The dark surround causes the image elements to appear lighter than those viewed in an illuminated surround. For this reason, it is worthwhile to briefly review the general results of brightness sealing under a various viewing condition. Two of the most often cited parers on the topic of brightness scaling are Stevens-stevens and Bartleson-Breneman's function. There are, however, significant differences between the perceptual functions for simple-field and complex-field viewing. In this paper, we research the relationship between Steven's power law and Bartleson-Breneman's function. We present an appropriate brightness perception function due to TV system viewing conditions. Highlight luminance peak and absolute brightness threshold value in various adaptation levels are obtained from the proposed brightness function . Also, the luminance value of black level to produce the same contrast ratio with variety of display highlight luminance peak is obtained from the proposed brightness function.

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