• Journal of Korean Clinical Health Science
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• v.4 no.2
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• pp.550-555
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• 2016

Purpose. We compared with the refracting power and aberration according to the measurement change in illumination and the pupils area by using the auto refraction instruments. Methods. In this study it were examined 64 eyes without eye disease, 21.4 (${\pm}2.54$) age, 32 (male 10, female 22) patients. Experiments in general illumination using the auto refraction instruments (HRK-8000A, Huvitz, Korea) was measured in both eyes 3 times and after scotopic for 30 minutes in a dark room blocked the light was measured in the same way. Aberration were measured coma, spherical aberration, high and low order aberrations in a general illumination (3500 lux) and low illumination (5 lux) of the pupil area 3.96 mm and 5.96 mm. Results. In the general illumination for measuring of the pupil area, the refractive power, coma, spherical aberration and low order aberration was no significant difference. In the low illumination, spherical aberration of the pupil area was $0.005({\pm}0.015){\mu}m$ in a 3.96mm, $0.014({\pm}0.020){\mu}m$ in a 5.96 mm and appeared a significant difference(p = 0.003). In general and low illumination on the results of comparing the measured values of the refractive power and aberration at the pupil area 3.96 mm, high order aberrations was $0.205({\pm}0.145){\mu}m$ in general illumination, $0.132({\pm}0.075){\mu}m$ in low illumination and appeared a significant differences(p = 0.001). High order aberrations at the pupil area 5.96 mm was $0.278({\pm}0.244){\mu}m$ in general illumination, $0.150({\pm}0.092){\mu}m$ in low illumination and appeared a significant differences(p = 0.000). Conclusions. When the eye refractive power measured by the automatic refraction does not depend on the illumination conditions and size of the observation pupil area, it was found that aberrations are affected by the illumination and the observation pupil area. It was found that the eye examination chamber illumination to obtain accurate measurement produces better results to decrease than to increase.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.8
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• pp.900-906
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• 2005

The responses of two luminescence-based biosensors were studied on various heavy metals in aqueous solutions. One was recombinant E. coli ($DH5{\alpha}$/pSB311), genetically modified luminescence-based bacteria, and the other was Vibrio fisheri used for the LumisTox system. The recombinant E. coli was marked with the lux CDABE gene from multicopy plasmid, pACYC184, originally isolated from Photorhabdus luminescens. The $DH5{\alpha}$/pSB311 had a characteristic of no organic substrate for its luminescence reaction. Among the tested heavy metals Zinc and cadmium were less toxic than copper and mercury. The recombinant E. coli was more sensitive to toxicity of heavy metals than the LumisTox. The order of toxicity of the heavy metals to the recombinant E. coli was $Hg^{2+}>Cu^{2+}>Zn^{2+}>Cd^{2+}$. In case of the LumisTox, the order of the toxicity of heavy metals was $Hg^{2+}>Cu^{2+}>Cd^{2+}>Zn^{2+}$. The genetically modified luminescence-based biosensor offers a range of sensitive, rapid, and easy to use methods for assessing the potential toxicity of heavy metals in aqueous samples.

• Korean Journal of Microbiology
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• v.44 no.2
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• pp.85-92
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• 2008

Pseudomonas aeruginosa is an opportunistic human pathogen, causing a wide variety of infections including cystic fibrosis, microbial keratitis, and burn wound infections. The cell-to-cell signaling mechanism known as quorum sensing (QS) plays a key role in these infections and the QS systems of P. aeruginosa have been most intensively studied. While many literatures that introduce the QS systems of P. aeruginosa have mostly focused on two major acyl-homo serine lactone (acyl-HSL) QS signals, N-3-oxododecanoyl homoserine lactone (3OC12) and N-butanoyl homoserine lactone (C4), several new signal molecules have been discovered and suggested for their significant roles in signaling and virulence of P. aeruginosa. One of them is PQS (Pseudomonas quinolone signal; 2-heptyl-3-hydroxy-4-quinolone), which is now considered as a well-characterized major signal meolecule of P. aeruginosa. In addition, recent researches have also suggested some more putative signal molecules of P. aeruginosa, which are diketopiperazines (DKPs) and pyocyanin. DKPs are cyclic dipeptides and structurally diverse depending on what amino acids are involved in composition. Some DKPs from the culture supernatant of P. aeruginosa are suggested as new diffusible signal molecules, based on their ability to activate Vibrio fischeri LuxR biosensors that are previously considered specific for acyl-HSLs. Pyocyanin (1-hydroxy-5-methyl-phenazine), one of phenazine derivatives produced by P. aeruginosa is a characteristic blue-green pigment and redox-active compound. This has been recently suggested as a terminal signaling factor to upregulate some QS-controlled genes during stationary phase under the mediation of a transcription factor, SoxR. Here, details about these newly emerging signaling molecules of P. aeruginosa are discussed.

• Journal of Korean Society for Geospatial Information Science
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• v.23 no.1
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• pp.129-135
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• 2015

The Ubiquitous City (U-City) spatial information technology aimed to provide services freely anytime and anywhere by converging high-tech information & communication technology in urban infrastructure has been available in diverse patterns. In particular, there have been studies on the development of 3D spatial information after selecting and matching key points with stereo images from the many Closed Circuit TV (CCTV) in the U-City. However, the data mostly used in extracting matching points haven't considered external environmental impacts such as illuminance. This study tested how much the matching points needed to construct 3D spatial information with the CCTV whose image quality is dependent upon changes in illuminance fluctuate under the same hardware performances. According to analysis on the number of matching points by illuminance, the number of matching points increased up to 3,000Lux in proportion to the illuminance when IRIS, shutter speed and ISO were fixed. In addition, a border between an object and background became more distinctive. When there was too much light, however, the page became brighter, and noise occurred. Furthermore, it was difficult to name key points because of the collapse of an inter-object border. It appears that if filmed with the study results, the number of matching points would increase.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.5
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• pp.476-479
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• 2002

We observed the succession and appearence species of the marine benthic diatoms for the effective seed production of shellfish culture on wave plates in indoor mass culture tanks. Every five days, the existence species and densitiy of diatoms were counted during the 20 culture days. Experimental conditions were 8.5 $\pm$ 0.3$^{\circ}C$ of water temperature, 1.0250$\~$1.0260 of specific gravity, 2,200$\~$13,000 lux of light intensity. The total density of appearence species was rapidly increased with the lapse of time. However, the number of appearence species decreased on the 20th day. The diatoms observed were 10 species; Navicula sp. of, viridula, Cylindrotheca closterium, Licmophora sp., Pleurosisma normnii, Bacillaria Paradoxa Asterionella glacialis, Stephanopuis sp. cf, turris, Entomoneis sp., Odontella aurita and Cocconeis sp, cf, scutellum. Of them, Navicula sp, of, viridula was most dominant throughout the experiment.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.4
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• pp.289-298
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• 2014

Purpose: This study was designed to investigate the present conditions of illumination techniques in dental laboratories in order to distinguish colors for esthetic dentistry. Materials and Methods: A total of forty-eight local dental laboratories were selected for sampling a) luminous intensity and b) color temperature. We measured the luminous intensity and the color temperature on a center point of porcelain table with lux meter and color meter respectively. The measurements were performed twice, once on a clear day and on a cloudy day between 12 pm and 2 pm (day light and artificial illumination) and between 7 pm and 10 pm (artificial illumination only). Results: The results obtained were as follows. 1. The average luminous intensity in dental laboratories lighting was 1871 lx, and 67% of dental laboratories had luminous intensity greater than 1600 lx, which was appropriate for operations related to colors, while 33% of dental laboratories had in sufficient lighting for appropriate luminous intensity. 2. The average color temperature in dental laboratories lighting was 6506 K, which was inappropriate for operations related to color. None of the dental laboratories had a color temperature range of 5000 - 5500 K, which is appropriate for operations related to colors. 3. Between daytime and nighttime, also between clear day and cloudy day, the average luminous intensity and color temperature in dental laboratories were not significantly different. Conclusion: Illumination in most dental laboratories selected in this study was inappropriate for operations related to color.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.5
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• pp.482-488
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• 2000

The stability of c-phycocyanin and spectral property of phycobilins obtained from Spirulina platensis cultured by helical tubular photobioreactor were determined. The c-phycocyanin with maximal absorption of 622 nm and allophycocyanin with maximal absorption of 652 nm fractions were isolated from phycobilins by Sephadex G-100 gel chromatoBraphy, The yield of partially purified c-phycocyanin was about $1.5{\%}$ to dried biomass. The stability of c-phycocyanin in the range of $pH 4{\~}9$ was high but c-phvcocvanin was unstable over pH 10. The c-phycocyanin was stable at temperatures below $40^{\circ}C$, and at light intensity below 15000 lux. And metal ions were not affect the stability of c-phycocyanin.

• The Korean Journal of Mycology
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• v.11 no.3
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• pp.121-128
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• 1983

Nutritional and physio-chemical conditions for mycelial growth and fruit-body formation of Pleurotus florida were determined in synthetic media. Mannitol and sucrose were good sugar substances for the mycelial growth and fruit-body formation whereas less mycelial growth and no fruit-body formation was obtained with arabinose, lactose and inulin. The optimum concentration of mannitol was about 2%. Peptone as a nitrogen sources resulted in a rapid mycelial growth and fruit-body formation with higher yield, but nitrite-nitrogens inhibited the mycelial growth. The higher yield was obtained with 0.2% peptone. Among the vitamins used, the greatest mycelial growth and fruit-body formation brought about by thiamine and folic acid. $KH_2PO_4$ and $MgSO_4$ at 0.2% and 0.02%, respectively, were effective for the mycelial growth and fruit-body formation, but other inorganic salts used were ineffective. The optimum temperature for mycelial growth and fruit-body formation were $25^{\circ}C$ and $20^{\circ}C$, respectively, and light intensity of $100{\sim}500\;lux$ and pH 6.0 appeared to be effective.

• Food Science of Animal Resources
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• v.23 no.3
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• pp.200-208
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• 2003

This study was carried out to investigate the influence of dietary germanium supplementation on the meat quality of duck. Ducks raised for 42 days were slaughtered and the ground meats were stored at 3$^{\circ}C$ for 12 days under 1200 lux. Experimental treatments were divided into 3 kinds of meat from ducks fed germanium as follows; 1) Control(natural water + commercial feed), 2) T1(1～10 days: natural water + commercial feed, 11-42 days: natural water + commercial feed supplemented with 1 % germanium), 3) T2(1～10 days: germanium submersion water + commercial feed, 11～42 days: natural water + commercial feed supplemented with 1 % germanium). The pH of duck meat was not different among the treatments(p>0.05). The germanium treatments exhibited significantly higher crude fat content in both breast and thigh meat(p<0.05). In the fatty acid composition, T2 contained more unsaturated fatty acid than control or Tl. TPA(textural profile analysis) value such as hardness, gumminess, chewiness and adhesiveness decreased in meat from duck fed supplemental germanium. Cholesterol contents of duck meat decreased in dietary supplemental germanium treatment compared to control, but were not significantly different among them(p>0.05). Dietary germanium supplementation affected on lipid oxidation of meat during storage. TBARS of meat from duck fed germanium was lower than that of control(po.05). The CIE L*, b* and h$\^$0/ values of germanium treatments were significantly(p.o5) higher than those of control. Also a* value showed more stable in germanium diet treatment during storage. Therefore, dietary supplemental germanium to duck resulted in light brownish color formation, improvement tenderness and retardation of lipid oxidation of meat during refrigerated storage.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.664-668
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• 2001

The physical and chemical stabilities of carthamin of red pigment from safflower petals were investigated at various conditions of pHs, temperatures, inorganic ions, sugars, light and polysaccharides. The half-life values at pH 3.0, 5.0, 9.0 and 11.0 were 5.3, 5.0, 11.0 and 45.0 h, respectively, at $25^{\circ}C$. Therefore, carthamin is unstable at acidic condition. Carthamin was red, orange and yellow at acidic, neutral and alkaline solutions, respectively. At pH 3.0, carthamin was thermally unstable and the half lives were 3.62, 9.05 and 48.2min at $90^{\circ}C$, $70^{\circ}C$ and $50^{\circ}C$, respectively. Among various inorganic ions, $Al^{3+}$ stabilized carthamin at acidic condition. At pH 5.0, carboxymethylcellulose prolonged the half-lives of carthamin at $25{\sim}90^{\circ}C$. Carthamin was very sensitive to light (20,000 lux) and the half-life was 2.32 min at pH 3.0.