• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.5
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• pp.443-453
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• 2012

This study examines visual perception and spatial satisfaction according to lighting conditions. Field measurements and surveys were performed in three rest space of university buildings where various lighting conditions were employed. Results indicate that overall impression of space improved when low color temperature, such as 3,000 K governed overall lighting environment and accent lighting was used for wall surfaces. Lighting conditions that kept uniform illuminance levels using area light sources containing fluorescent lamps with 6,500 K failed to keep favorable spatial satisfaction for space. High color temperature was not recommended for lighting in rest space. Asymmetrical illuminance levels formed by low color temperature such as 3000 K is recommended to keep positive mood and improve spatial satisfaction in rest space. Overall impression of the space was influenced by visual comfort, color temperature, spatial satisfaction and brightness. Spatial satisfaction for space was effectively impacted by psychological comfort, color temperature and overall impression for lighting conditions. Psychological comfort in space was influenced by color temperature, spatial satisfaction and visual annoyance from reflected light.

• Journal of the Korean Wood Science and Technology
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• v.51 no.4
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• pp.270-282
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• 2023

Lower termites need symbiotic microbes for cellulose digestion. Elizabethkingia miricola strain BM10 has been proposed as a symbiotic microbe that assists in low-temperature digestion and metabolism of Reticulitermes speratus KMT1, a termite on Bukhan Mountain, Seoul, Korea. In E. miricola strain BM10, β-glucosidase genes expressed at 10℃ were identified, and the psychrophilic enzymatic characteristic was confirmed by heterogeneously expressed proteins. Crude β-glucosidase in the culture broth of E. miricola strain BM10 showed specific enzymatic properties, and its substrate affinity was 4.69 times higher than that of Cellic CTec2. Among the genes proposed as β-glucosidase, two genes, bglB_1 and bglA_2, whose gene expression was more than doubled at 10℃ than at 30℃, were identified. They were heterogeneously expressed in Escherichia coli and identified as psychrophilic enzymes with an optimal reaction temperature of about 20℃-25℃. In this study, E. miricola strain BM10, a symbiotic bacterium of lower termites, produced psychrophilic β-glucosidases that contribute to the spread of the low-temperature habitat of a lower termite, R. speratus KMT1.

• Journal of Microbiology and Biotechnology
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• v.15 no.1
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• pp.125-130
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• 2005

The growth and phosphatase (phosphomonoesterase) activity of Chroococcidiopsis culture isolated from the cryptoendoliths of the Antarctic were compared with a similar isolate from the Arizona hot desert. Such cyanobacteria living inside rocks share several features with the immobilized cells produced in the laboratory. This study has relevance because the availability of phosphorus is a key factor influencing the growth of these cyanobacteria in nature, in such unique ecological niches as the hot and cold deserts. Phosphatase activity therefore is of particular importance for these organisms if they are to survive without any other source of phosphorus availability. Also, there is paucity of knowledge regarding this aspect of study in cyanobacterial cultures from these extreme environments. The salient feature of this study shows the importance of specific pH and temperatures for growth and phosphatase activity of both cultures, although there were marked differences between the two isolates. The pH and temperature optima for growth and phosphatase activity (PMEase) of Chroococcidiopsis 1 and 2 were 9.5, $240^{\circ}C$ and 8.5, $40^{\circ}C$ respectively. The $K_m and V_max$ values of cultured Chroococcidiopsis 1 showed lower affinity of PMEase for the substrate compared to the enzyme affinity of the same organism when found within the rocks; Chroococcidiopsis 2 and Arizona rocks containing the same alga however showed similar affinity of PMEase for the substrate. An interesting observation was the similarity in response of immobilized Chroococcidiopsis 1 culture and the same organism in the Antarctic rocks to low light and low temperature stimulation of PMEase. This thermal response seems to be related to the ability of the immobilized Antarctic isolate and the rocks to either cryoprotect the PMEase or undergo a change to save the enzyme from becoming nonfunctional under low temperatures. The free cells of Chroococcidiopsis 1 culture however did not show such responses.

• The Research Journal of the Costume Culture
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• v.26 no.5
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• pp.754-763
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• 2018

This study examined the color reproducibility and color fastness of digital textile printing for nylon sublimation transfer. After measuring the temperature and time suited to nylon sublimation transfer, the researchers conducted various tests for comparison and analysis including polyester transfer paper on polyester fabric to check dyeing characteristics, color change, sharpness, and the rubbing fastness of the dyeing samples for nylon sublimation transfer. These tests produced the following results. At $185^{\circ}C$ and $187^{\circ}C$, the sublimation transfer dyeing characteristics of nylon were similar to those of polyester and the researchers even observed superior color development in some colors; at a low temperature of $180^{\circ}C$, the sample that was worked on had the lowest level of color development. The examination of color difference (${\Delta}E$), which compared $L^*a^*b^*$ values, showed that the ${\Delta}E$ value of magenta was 10.34, that of yellow was 24.70, and that of black was 15.28. These results highlight the important role of heat treatment temperature and time on color development in nylon sublimation transfer. Concerning sharpness, the samples subjected to higher temperature heat treatment exhibited fewer color spreading phenomena around lines. Thus, dyeing properties and fastness can be enhanced by elongating time at low temperatures and shortening time at high temperatures; however, considering production time constraints as well as the need to produce industrially marketable quantities, the findings of this study suggest that the heat treatment temperature most suitable for nylon sublimation transfer is $187^{\circ}C$ for a duration of 50 seconds.

• Korean Journal of Medicinal Crop Science
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• v.3 no.3
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• pp.233-239
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• 1995

The effects of media, growth regulators, low-temperature treatments, culture temperature and light were investigated to improve the callus induction and growth in the anther culture of Comus officinalis Sieb. et Zucco. The frequency of callus induction was more effective on WPM medium than MS medium, and it was highest as 54% in WPM medium supplemented with Img/L NAA. Callus growth was stimulated on MS medium supplemented with 2mg/L NAA. Effect of temperature and light on the callus induction and growth was highest as 62% in the treatment for 16/8 hrs. (light/dark) at $25^{\circ}C$ Ef­fect of low - temperature treatment on callus induction was highest as 19. 5% in the treatment for 36 hrs. at $4^{\circ}C$. For organization, green cells and rootings were promoted on MS medium supplemented with O. 5mg/L 2,4-D and 1 mg/L kinetin. The prevention of callus browning was effective on the medium con­taining $3{\sim}5mg/L$ ABA or 5mg/L $AgNO_3$. The supplement of ABA or $AgNO_3$,were maintained callus ac­tivity for 4-5 weeks and they were promoted the development of green cells.

• Microbiology and Biotechnology Letters
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• v.34 no.1
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• pp.47-51
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• 2006

Sodium butyrate (NaBu) is used as an enhancer for the production of recombinant proteins in Chinese hamster ovary (CHO) cells. However, NaBu is well-known for its cytotoxic effect, thereby inducing apoptosis. CHO cells which had been engineered to express a humanised anti-HBV antibody were cultured using serum-free medium, Ex-cell 301. From a seeding density of $2{\times}10^5$ cells/ml, CHO cells grown with serum-free medium reached a maximum cell density of $1.3{\times}10^6$ cells/ml after 9 days in culture and produced a maximal antibody concentration of 130 mg/l after 13 days in culture. In the perfusion culture system, CHO cells producing anti-HBV antibody grown in an 7.5 1 bioreactor seeded with $2{\times}10^5$ cells/ml reached a maximal antibody concentration of 85 mg/1 after 720 h in culture. The addition of 0.3 mM NaBu and lowering culture temperature to $33^{\circ}C$ elongated the culture period to 60 days and increased the production yield by 2-fold, compared to control culture.

• Korean Journal of Ecology and Environment
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• v.41 no.1
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• pp.26-33
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• 2008

To understand the effect of water temperature on growth pattern of Stephanodiscus sp., we weekly or biweekly investigated in the lower part of the Nakdong River from 1994 to 2006 and performed a laboratory experiment. Stephanodiscus was the most dominant species among phytoplankton in winter when low flow persisted and the high abundances of the species were maintained from December to February. Three strains of Stephanodiscus sp. were isolated for the in vitro experiment from the Nakdong River in January 2005. Over the water temperature range of $4^{\circ}C$ to $20^{\circ}C$, the growth patterns of Stephanodiscus sp. were different in the short-term batch culture. The maximum cell density of Stephanodiscus sp. was observed at approximately $5^{\circ}C$ in the river systems, but the optimum water temperature of Stephanodiscus sp. was $10^{\circ}C$ for the growth in the laboratory experiment. However, the proliferation of Stephanodiscus sp. was related to low water temperature in the Nakdong River.

• The Research Journal of the Costume Culture
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• v.11 no.1
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• pp.66-74
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• 2003

This study is to improve the worst lightfastness of a natural dye. To modify the fiber surface, low temperature oxygen plasma was carried out on silk fabric. The result is followed below after the examination of surface shape, dyeability, color change, UV absorbent influence and lightfastness. 1. When electric discharge outputs are 60W, 80W and 100w, and processing times are 10minutes, 20minutes and 40minutes, the etching effect of surface increased as electric discharge outputs and processing times increased. 2. When examined UV absorbent for 5hours, 10hours, 20hours, 40hours and 80hours, the value changes of E are 1.47, 2.51, 2.91, 3.71, 4.51 and 5.31 in case of Al pre-mordanting/ prasma 80W, 20min./ UVabsorbent 5% (100:1), 2.31, 2.47, 3.84, 3.90, 3.61 and 4.42 in case of Al pre-mordanting/prasma 80W, 20min.1 UV absorbent 5% (o.w.f.). The lightfastness decreased when UV absorbent increased. 3. Dyeability of the samples pre-treated with five different methods was in the following order: plasma processing for 20minutes at 60W/Al pre-mordanting > Al pre-mordanting > plasma processing for 20minutes at 60W > Al after-mordanting. non mordanting Plasma treatment had superior effect on dyeability. 4. When UV absorbent was applied in fabric, the sample under higher electric discharge out puts showed more effective in improving lightfastness.

• Journal of Plant Biotechnology
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• v.7 no.2
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• pp.135-141
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• 2005

Protocols for in vitro conservation was developed for Coleus forskohlii. Plants maintained both in field served as explant source. Shoot tips and single node cuttings were used to optimize protocols for in vitro multiplication. MS basal medium supplemented with $0.54\;{\mu}M$ naphthalene acetic acid (NAA) and $8.87\;{\mu}M$ benzy-ladenine (BA) induced multiple shoots in shoot tips and nodes. Shoot multiplication was amplified with a gradual decrease of BA concentration, leading to its final omission after 4 months. Concomitant rooting on multiplication media enabled successful establishment extra vitrum. For in vitro conservation studies, experiments were carried out with 2-3 week maintained in vitro plants under standard and reduced culture conditions (SCC, RCC). In vitro plants could be successfully conserved in full strength MS medium (FMS) under SCC for 6 months without subculture with full potential to regenerate, producing viable shoots and nodes. The root production remained unaffected due to conservation, showing high rooting activity in mannitol and low temperature treatments. Preset low temperature (15 and $10^{\circ}C$) and reduction in media constituents does not appear to favour conservation, although the former accomplished conservation levels equal to (FMS) under SCC.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.1
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• pp.10-15
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• 2002

Environmental and medium factors were investigated as basic data for optimizing DHA production when using Thraustochytrium aureum. To study the effect of environmental conditions, the rotation speed and culture temperature were changed. Plus the trend of the growth characteristics, lipid content in the biomass, and DHA content in lipids were evaluated according to various initial glucose concentrations. The biomass, lipid, and DHA analyses showed that the physiological characteristics of T. aureum were closely related with the environmental and medium conditions, as in the case of other marine microorganisms. For example, a low rotation speed of 50 rpm lowered the cell growth rate as well as the DHA content in the lipids. A low temperature had a negative effect on the cell growth, yet a positive effect on the lipid content in the biomass. Different initial glucose concentrations had no effect on the lipid content in the biomass or DHA content in the lipids, yet did affect the cell growth. Accordingly, these results show that environmental and medium factors must be synthetically considered in order to optimize DHA production when using T. aureum.