• Natural Product Sciences
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• v.2 no.2
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• pp.90-95
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• 1996

When reserpine-producing cell strains of Rauwolfia serpentina were transferred from the dark to the light irradiation, the production of reserpine was extremely enhanced whereas the cell growth was suppressed. In an incubation period of 20 days, the most effective culture condition for reserpine production was the combination of 8 days of dark culture and following 12 days of light culture. The time courses of both cell growth and reserpine production were measured in vitro in order to clarify the effect of wave length range of light on the biosynthesis of reserpine. Although the growth of cultured cells which had been incubated under continuous red, yellow, and green lights, respectively, was similar to that of the cultured cells subcultured in the dark. The cells cultured under red light irradiation produced less reserpine than dark-grown cultures. Both blue and near-ultraviolet light inhibited the growth of cultured cells. The production of reserpine was strikingly enhanced by blue light, but was strongly inhibited by near-ultraviolet light.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.6
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• pp.349-353
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• 2003

The physiological characteristics of cultures of very high cell mass (e.g. 10g cell mass/L), termed“ultrahigh cell density cultures”is reviewed. A close relationship was found between the length of the optical path (OP) in flat-plate reactors and the optimal cell density of the culture as well as its areal (g m$\^$-2/ day$\^$-1/) productivity. Cell-growth inhibition (GI) unfolds as culture density surpasses a certain threshold. If it is constantly relieved, a 1.0cm OP reactor could produce ca. 50% more than reactors with longer OP, e.g. 5 or 10cm. This unique effect, discovered by Hu et al. [3], is explained in terms of the relationships between the frequency of the light-dark cycle (L-D cycle), cells undergo in their travel between the light and dark volumes in the reactor, and the turnover time of the photosynthetic center (PC). In long OP reactors (5cm and above) the L-D cycle time may be orders of magnitude longer than the PC turnover time, resulting in a light regime in which the cells are exposed along the L-D cycle, to long, wasteful dark periods. In contrast, in reactors with an OP of ca. 1.0 cm, the L-D cycle frequency approaches the PC turnover time resulting in a significant reduction of the wasteful dark exposure time, thereby inducing a surge in photosynthetic efficiency. Presently, the major difficulty in mass cultivation of ultrahigh-density culture (UHDC) concerns cell growth inhibition in the culture, the exact nature of which is awaiting detailed investigation.

• Mycobiology
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• v.34 no.2
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• pp.83-91
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• 2006

Characteristic growth patterns of Cordyceps militaris isolates on various media, under varying light conditions and at varying incubation periods were examined. Light was found to be the most critical single factor in determining the density, texture, and pigmentation of the mycelial culture of the fungus. However, under the light condition, the degree of pigmentation and mycelial density were found to be affected by the incubation period and type of medium. Irrespective of the variations in medium type or incubation period, there was no pigmentation of the mycelium under dark condition. Radial growth of the mycelium was faster under dark incubation rather than under light incubation. Abundant mycelial density and darkest pigmentation of C. militaris isolates were produced in nutritionally rich media like SDAY, SMAY and CZYA, suggesting that these media may fulfill all the requirements for vegetative growth of the fungus. Growth characteristics of C. militaris isolates could be easily observed by the simple agar culture method, which would be useful to characterize the phenotypic characteristics of large number of pure cultures of the fungus under given conditions of growth factors such as medium, light and temperature.

• Journal of Microbiology and Biotechnology
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• v.22 no.3
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• pp.400-406
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• 2012

To improve the hydrogen yield from biological fermentation of organic wastewater, a co-culture system of dark- and photo-fermentation bacteria was investigated. In a pure-culture system of the dark-fermentation bacterium Clostridium butyricum, a pH of 6.25 was found to be optimal, resulting in a hydrogen production rate of 18.7 ml-$H_2/l/h$. On the other hand, the photosynthetic bacterium Rhodobacter sphaeroides could produce the most hydrogen at 1.81mol-$H_2/mol$-glucose at pH 7.0. The maximum specific growth rate of R. sphaeroides was determined to be 2.93 $h^{-1}$ when acetic acid was used as the carbon source, a result that was significantly higher than that obtained using either glucose or a mixture of volatile fatty acids (VFAs). Acetic acid best supported R. sphaeroides cell growth but not hydrogen production. In the co-culture system with glucose, hydrogen could be steadily produced without any lag phase. There were distinguishable inflection points in a plot of accumulated hydrogen over time, resulting from the dynamic production or consumption of VFAs by the interaction between the dark- and photo-fermentation bacteria. Lastly, the hydrogen production rate of a repeated fed-batch run was 15.9 ml-$H_2/l/h$, which was achievable in a sustainable manner.

• Korean Journal of Microbiology
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• v.7 no.1
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• pp.1-9
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• 1969

Changes in the phosphorylation of Chlorella cells during the life cycle the aulotrophic and micotrophic synchronous culture were followed under the light and dark. 1. In the autotrophic culture of Chlorella the amounts of esterified phosphate compounds of the algal cell under the light increased during the growing period and decreased strikingly in the ripening period showing a peak at the $L_1$ i/-cell stage. 2. TRhe amount of total esterified phosphate compounds of the cell under the dark, however, decreased during the growing period and then kept fairly constnat during the ripening nad division periods showing the greates activity of the oxidative phosphorylation in the early growing stage. 3. It is presumed that the energy requirement of the dividing algal cell in the autotrophic culture is fulfilled prior to the nuclear division mostly by the photosynthetic phosphorylation. 4. In the mixotrophic culture, the amount of esterified phosphate compounds of the algal cells under the light increased during the growing period and decreased during the late ripening and early division periods showing a peak in the $L_2$-cell stage as in the case of the phosphorylation under the dark. 5. The phosphorylation of the fell grown in the glucose medium is more active under the dark than under the light in the stages of the growing and early ripening periods. 6. It is considered that the excess glucose in the algal cell not only promotes the oxidative phosphorylation but also inhibits the photosynthetic phosphorylation of the cell. 7. It is presumed that the energy requirement of the dividing algal cell in the glucose medium is fulfilled prior to the nuclear division by the combined action of oxidative and photosynthetic phosphorylation, mostly by the oxidative phosphorylation.

• The Journal of the Convergence on Culture Technology
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• v.10 no.1
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• pp.137-142
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• 2024

User interface (UI) functions are distorted and appear as a dark pattern that intentionally deceives or entices users. Consumers who are unaware of dark patterns are constrained in their choices, resulting in unnecessary economic damage. In this study, we aimed to investigate consumers' various shopping emotions and behavioral intentions after recognizing dark patterns in online shopping malls through qualitative research methods. As a result of the study, the rate of perception differed slightly depending on the type of dark pattern, and it was found that it induced consumer emotions such as distrust of the company, user deception, and displeasure. It has been found that the behavior after recognizing the dark pattern shows passive behaviors such as vowing to prevent recurrence and warning acquaintances rather than actively protesting to the company and demanding compensation for damages.

• KSBB Journal
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• v.16 no.6
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• pp.568-572
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• 2001

Light is one of the most important environmental factors controlling plant physiology. The human granulocyte-macrophage colony-stimulating factor (hGM-CSF) was produced from cell suspension cultures of transgenic tobacco under different light conditions (24 hr light, 18 hr light/dark cycle, dark). Under 24 hr light condition, cell growth was best and dry cell weight reached 14.4 g/L. Light did not influenced the secretion of total proteins. However, in the dark condition, the ratio of secreted total protein/dry cell weight was 1.5 fold higher than those of ethel conditions. Production of hGM-CSF was highest with 18 hr light condition and reached 496.5 ug/L. In addition, the content of hGM-CSf in secreted total proteins was 1.8 fold higher than that of 24 hr light condition, which is beneficial for the purificationof the protein.

• The Research Journal of the Costume Culture
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• v.15 no.5
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• pp.838-851
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• 2007

The purpose of this research was to investigate the harmony evaluation and the effects used clues on harmony perception in terms of 128 contrast coloration of male shirt and necktie by male and female students. The results are as follows. Among 128 contrast coloration stimuli, female students evaluated 42 set, male students 50 set, so proved that male's range of harmony more extensive than that of female. It is significant difference between female and male on shirt-necktie coloration; vivid red shirt-vivid green tie, dull red shirt-dark blue tie, light red shirt-dull blue tie, dark red shirt-light blue tie, light green shirt-vivid violet tie, light green shirt-light red tie, light green shirt-dull red tie. Especially, in contrast coloration, it was evaluated as harmonized coloration by both male and female as tie was dark tone on the whole.

• International Journal of Advanced Culture Technology
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• v.8 no.4
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• pp.229-234
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• 2020

Dehazing significantly improves image quality by restoring the loss of contrast and color saturation for images taken in the presence. However, when applied to images not taken according to the prior information, dehazing can cause unintended degradation of image quality. To avoid unintended degradations, we present a hazy scene detection algorithm using a single image based on the distributions of hue, saturation, and dark channel. Through a heuristic approach, we find out statistical characteristics of the distribution of hue, saturation, and dark channels in the hazy scene and make a detection model using them. The proposed method can precede the dehazing to prevent unintended degradation. The detection performance evaluated with a set of test images shows a high hit rate with a low false alarm ratio. Ultimately the proposed method can be used to control the effect of dehazing so that the dehazing can be applied to wide variety of images without unintended degradation of image quality.

• The Journal of the Convergence on Culture Technology
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• v.6 no.1
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• pp.361-366
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• 2020

The Korean movies, and are suitable for "B-movie" for spending low budget and utilizing subculture factors such as kitsch, parody. Using surrealistic space and arbitrary language is the most prior element in constituting 'B-affection'. In that sense, Behind the Dark Night, Super Margin have characteristics overcrossing the media from comics to film. Despite absurd story, Behind the Dark Night has a realistic and concrete sense of what is the making films. The hero in Super Margin was swindled, so he strikes a blow the breeding-place of crime himself. In conclusion, showing comics characteristic aspects has been increasing comedy effects. But, on the other hand, Behind the Dark Night, Super Margin have pointed out that there are many kind of social problems such like career, fraud etc. In addition, they introspect the meaning what is that to making films.