• Journal of the Korean Society for Marine Environment & Energy
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• v.10 no.2
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• pp.93-101
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• 2007

In order for bioremediate the benthic layer in polluted inner Bay, the effects of irradiance and wave-length irradiated from light emission diode (LED) on the growth of benthic diatom Nitzschia sp. (Hakozaki Bay strain of Japan) were investigated. The Nitzschia sp. was cultured under blue LED (450 nm), yellow LED (590 nm), red LED (650 nm) and fluorescent lamp (mixed wavelengths). At $25^{\circ}C$ and 30 psu, the growth of Nitzschia sp. showed its peak at $20\;{\mu}mol\;m^{-2}\;s^{-1}$ (blue LED) and $40\;{\mu}mol\;m^{-2}\;s^{-1}$ (fluorescent lamp), and was inhibited at the irradiance higher than that irradiance. Nitzschia sp. in yellow LED and red LED is fitted by a rectangular hyperbolic curve because no photoinhibition was observed under maximum irradiance used in this study. The irradiance-growth curves were described as ${\mu}=-0.46{\exp}(1-I/6.32)+0.46-0.00043I,\;(r^2=0.98)$ under blue LED, ${\mu}=0.42(I+7.87)/(I+58.9),\;(r^2=0.99)$ under yellow LED, ${\mu}=0.39(I+3.39)/(I+21.6),\;(r^2=0.94)$ under red LED, ${\mu}=-0.38{\exp}(1-I/7.23)+0.38-0.00016I,\;(r^2=0.96)$ under fluorescent lamp. Maximum specific growth rate of blue LED, yellow LED, red LED and fluorescent lamp was $0.44\;day^{-1},\;0.42\;day^{-1},\;0.39\;day^{-1}$ and $0.37\;day^{-1}$, respectively. The absorption coefficient ($a_{ph}$) of Nitzschia sp. was similar under all the wavelengths (400 nm-700 nm), although maximum $a_{ph}$ was $0.0224\;m^2\;mg\;chi.\;{\alpha}^{-1}$ in 472 nm and $0.0179\;m^2\;mg\;chi.\;{\alpha}^{-1}$) in 663 nm. The results may indicate the possibility of environmental improvement around the benthic layer in polluted coastal area because microphytobenthos growth is stimulated by means of irradiated blue LED at the benthic boundary layer during both autumn and winter, and yellow LED, which might have been suppressed growth of harmful algae, at the layer during both spring and summer.

• Microbiology and Biotechnology Letters
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• v.34 no.1
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• pp.7-14
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• 2006

Feather, generated in large quantities as a byproduct of commercial poultry processing, is almost pure keratin, which is not easily degradable by common professes. Four strains, SMMJ-2, FL-3, NO-4 and RM-12 were isolated from soil for production of extracellular keratinolytic protease. They were identified as Bacillus sp. based on their morphological and physiological characteristics. They shown high protease activity on 5.0% skim milk agar medium and produced a substrate like mucoid on keratin agar medium. Bacillus sp. SMMJ-2 had a faster production time for producing keratinolytic protease than other strains. This strain did not completely degrade whole chicken feather for five days in basal medium but completely degraded whole chicken feather when supplied with nitrogen source for 40hours in keratinolytic producing medium ($0.7%\;K_{2}HPO_{4},\;0.2%\;KH_{2}PO_{4},\;0.1%$ fructose, 1.2% whole chicken feather, $0.01%\;Na_{2}CO_3$, pH 7.0). When supplied with chicken feather as nitrogen source, keratinolytic protease activity was 89 units/ml/min. When soybean meal was used as nitrogen source, the keratinolytic protease production reached a maximum of 106 units/ml/min after 48 hours under $30^{\circ}C$, 180 agitation. To isolate the keratinolytic protease, the culture filtrate was precipitated with $(NH_4)_{2}SO_4$ and acetone. The recovery rate of keratinolytic protease was about 96% after treatment with 50% acetone. The enzyme was stable in the range of $30{\sim}50^{\circ}C$ and pH $6.0{\sim}12.0$.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.1
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• pp.74-80
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• 1996

This experiment was conducted to obtain the basis of degradation of remaining agricultural chemicals accumulated in upland soils of Honam district in Korea. The population. relative growth rate(RGR). chlorothalonil(TPN)-degradation ability and bacterialogical characteristics of TPN resistant strains were investigated in TPN levels of 0, 25, 50, 100 and $500{\mu}l/ml$ compared with Mancozeb. A number of TPN-resistant bacteria were differ in the area of examined and were decreased with higher levels of TPN. The resistance of bacteria was stronger in TPN than Mancozeb but the resistance of fungi was vise versa. RGR of bacteria in the culture was the highest at the level of $50{\mu}l/ml$ and the lowest in $500{\mu}l/ml$ of TPN. TPN-degradation ability of bacteda isolated in various TPN levels was varied : only 8 percentage of bacteria showed 75 percentage or more degradation ability. The higher the concentration in TPN resistance, the larger the number of strains carried great ability to decompose pesticide residues. The strains having higher decomposition ability was rod-shapes cells and senstive to heat. Analyses of the indol production, methyl red, and V-P test have given similar results, with negative reaction in all these strain, while the other biochemical characteristics were differ in the strains. Based on these, these strains might be classified into Pseudomonas sp., Corynebacterium sp., Acinetobacter sp. and Moraxcella sp.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.10
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• pp.1690-1700
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• 2013

The objective of this study is to develop and validate predictive growth models for Bacillus cereus (diarrhea type) vegetative cells, spores and Staphylococcus aureus in preprocessed Namul (bracken and Chwinamul) and root vegetables (bellflower and burdock). For validation of model performance, growth data for S. aureus in preprocessed vegetables were collected at independent temperatures (18 and $30^{\circ}C$) not used in the model development. In addition, model performance of B. cereus (diarrhea type) in preprocessed vegetables was validated with an emetic type of B. cereus strain. In primary models, the specific growth rate (SGR) of the B. cereus spores was faster than that of the B. cereus vegetative cells, regardless of the kinds of vegetables at 24 and $35^{\circ}C$, while lag time (LT) of the B. cereus spores was longer than that of the B. cereus vegetative cells, except for burdock. The growth of B. cereus and S. aureus was not observed in bracken at temperatures lower than 13 and $8^{\circ}C$, respectively. The LT models for B. cereus (diarrhea type) in this study were suitable in predicting the growth of B. cereus (emetic type) on burdock and Chwinamul. On the other hand, SGR models for B. cereus (diarrhea type) were suitable for predicting the growth of B. cereus (emetic type) on all preprocessed vegetables. The developed models can be used to predict the risk of B. cereus and S. aureus in preprocessed Namul and root vegetables at the retail markets.

• Tuberculosis and Respiratory Diseases
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• v.60 no.3
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• pp.290-296
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• 2006

Background : IS6110 DNA fingerprint is a very useful tool for investigating the transmission of tuberculosis. The aim of this study was to identify the epidemiological situations within a given area (one province). Methods : The 681 Mycbobacterium tuberculosis isolates from patients, who were registered at health centers in Gyeonggi Province from May to December in 2004, were subjected to IS6110 DNA fingerprinting. Patients belonging to clusters were interviewed by health-workers to determine their previous contacts or household TB history. Results : The number of IS6110 copies of the 681 isolates showed diverse fingerprint patterns from 0 to 21 of which the most prevalent copy number was 10 from 120 isolates (17.6%). Thirty-three isolates (4.8%) belonged to the K strain, and 128 isolates (18.8%) belonged to the K family. There were 180 (26.4%) isolates belonged belonging to fifty clusters, of which two clusters were within household transmission. Forty-three (23.9%) out of 180 patients resided in an area under the same health center control. The rate of clusters in those aged 60-70 was higher than in any other age group ( 95% CI of RR : 1.072 ~ 1.988). Conclusion : This is the first report of an epidemiological survey based on a whole province using a DNA fingerprinting technique for M. tuberculosis. These results will be helpful in developing a program or policies to prevent the transmission of TB.

• Journal of Mushroom
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• v.12 no.2
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• pp.96-106
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• 2014

The primary objective of the present study is the characterization of the somatic hybrids of dikaryon-monokaryon (di-mono) crosses in mushroom breeding. We employed this technique for developing superior strains from Pleurotus ostreatus strains with 48 intraspecific hybrids of 12 combinations between six P. ostreatus strains and one P. florida strain. The results on the experiments of hybridization rate, nuclear DNA patterns, and colors and morphology of fruit-bodies, are presented. In di-mono crosses, somatic hybrids among Pleurotus strains showed 100% of crossability as seen in those between P. ostreatus and P. florida strains indicating that the nuclei of a dikaryon is inferred to be migrated to a recipient. 87.5% of the somatic hybrids among Pleurotus strains were similar to the donor dikaryons, and 12.5% of the somatic hybrids presented DNA patterns of both parents. In 16.6% of di-mono crosses between P. ostreatus and P. florida, the nuclear DNA patterns of all hybrids showed the same or similar patterns compared to the donor dikaryons. 70.9% of the hybrids between P. ostreatus and P. ostreatus were similar to the donor dikaryons and 12.5% of them presented the DNA patterns of both parents. 79.2% of fruiting body morphology of the hybrids among Pleurotus strains were similar to the dikaryons and 20.8% of them were similar to both parents. Interestingly, the morphology of all dikaryons were dissimilar each other. All hybrid strains between dikaryon P. florida and monokaryon P. ostreatus showed the fruiting body of which colors were similar to those of the dikaryon, while the hybrids between dikaryon P. ostreatus and monokaryon P. florida were showed the combined colors of both parents. Therefore, the fruiting body color of P. florida tends to be generally dominant. In conclusion, the present study provides a way to find out and suggest superior hybrid strains using the nuclear DNA patterns of hybrids between Pleurotus strains as well as the characteristics of their fruiting bodies. The advantages of the di-mono crossing are needs to be fully utilized in mushroom breeding because it is an ideal way to develop the superior strains of Pleurotus.

• Korean Journal of Poultry Science
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• v.30 no.1
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• pp.1-10
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• 2003

The objects of this study were to develop a new strain which has resistance to fowl typhoid, high performance in laying, and producing brown shell eggs favored by domestic consumers. Several White Leghorn (WL) breeds known as possessing genetic resistance to fowl typhoid and several brown shell egg breeds such as susceptible to the disease were used to produce the controlled strains with cross mating between the strains within the breeds and the experimental strains with crossbreeding between the breeds. The crossbred strains were Chungnong(CN) 21, 22, 23, 24, 25 and 26. The controlled strains were ISA brown CC, Hyline brown CC and Lohman brown CC. The survival rates were 99.95% for chicks of age 0∼l7 weeks and 91% for adult chickens of age 18∼72 weeks. There was no difference in survival rate between the crossbred and the controlled strains. The means of age of lst egg laying were 147 to 148 days and no difference was observed between the crossbred and the controlled. The egg Production rates of a9e 18∼72 weeks were 83.76% far the crossbred strains and 77.82% for the controlled strains, which is significantly higher in the crossbred than controlled strains by 6%. The numbers of the hen housed egg Production of age 18∼72 weeks were 292.33 eggs for the crossbred strains and 271.31 eggs fur the controlled strains. The difference of 21 eggs more produced by the crossbred than by the controlled was statistically significant. The mean egg weights of age 18∼72 weeks were 64.32g for the crossbred strains and 60.73g for the controlled strains, and the difference of 3.59g was statistically significant. The feed conversion rates during the age of 18 to 72 weeks were 2.297 for the crossbred strains and 2.454 for the controlled strains. The crossbreds were reduced feed consumption by 157g for 1kg of egg Production which was statistically significant. Haugh unit(H$.$u) at the age of 72 weeks were 82.20 for the crossbred strains and 77.82 for the controlled strains. The crossbred strains were superior quality by 4.38 H$.$u. There were no significant differences in the yolk color and the eggshell thickness between the crossbred strains and the controlled strains. The eggshell color of the crossbred strains was light brown which is the medium color of the white eggshell strains and the brown eggshell strains. The body weights at the ages of 8, 12, 18, 42 and 71 weeks were not different between the crossbred strains and the controlled strains.

• Journal of Plant Biotechnology
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• v.40 no.4
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• pp.210-216
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• 2013

Efficient regeneration methods and transformation system are a priority for successful application of genetic engineering to vegetative propagated plants such as grape (Vitis labrusca L.). This research is to establish shoot regeneration system from plant explants for 'Campbell Early', 'Tamnara', 'Heukgoosul', 'Heukbosek' using two types of plant growth regulators supplemented to medium. The highest adventitious shoot regeneration rate of 5% was achieved on a medium containing of Murashige and Skoog (MS) inorganic salts and Linsmaier and Skoog (LS) vitamins, 2 mg/L of TDZ and 0.1 mg/L of IBA. Leaf tissue of 'Campbell Early', was co-cultivated with Agrobacterium strains, LBA4404 containing the vector pBI121 carrying with CaMV 35S promoter, gus gene as reporter gene and resistance to kanamycin as selective agent, the other Agrobacterium strains, GV3101 containing the vector pB7 WG2D carrying with mPAP1-D gene. mPAP1-D is a regulatory genes of the anthocyanin biosynthetic pathway. 'Campbell Early' harboring mPAP1-D gene was readily able to be selected by red color due to anthocyanin accumulation in the transformed shoot. These results might be helpful for further studies to enhance the transformation efficiency in grape.

• Journal of the Korea Concrete Institute
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• v.25 no.5
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• pp.485-496
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• 2013

In recent years, frequent terror or military attacks by explosion or impact accidents have occurred. Examplary case of these attacks were World Trade Center collapse and US Department of Defense Pentagon attack on Sept. 11 of 2001. These attacks of the civil infrastructure have induced numerous casualties and property damage, which raised public concerns and anxiety of potential terrorist attacks. However, a existing design procedure for civil infrastructures do not consider a protective design for extreme loading scenario. Also, the extreme loading researches of prestressed concrete (PSC) member, which widely used for nuclear containment vessel, gas tank, bridges, and tunnel, are insufficient due to experimental limitations of loading characteristics. To protect concrete structures against extreme loading such as explosion and impact with high strain rate, understanding of the effect, characteristic, and propagation mechanism of extreme loadings on structures is needed. Therefore, in this paper, to evaluate the impact resistance capacity and its protective performance of bi-directional unbonded prestressed concrete member, impact tests were carried out on $1400mm{\times}1000mm{\times}300mm$ for reinforced concrete (RC), prestressed concrete without rebar (PS), prestressed concrete with rebar (PSR, general PSC) specimens. According to test site conditions, impact tests were performed with 14 kN impactor with drop height of 10 m, 5 m, 4 m for preliminary tests and 3.5 m for main tests. Also, in this study, the procedure, layout, and measurement system of impact tests were established. The impact resistance capacity was measured using crack patterns, damage rates, measuring value such as displacement, acceleration, and residual structural strength. The results can be used as basic research references for related research areas, which include protective design and impact numerical simulation under impact loading.

• The Korean Journal of Mycology
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• v.35 no.1
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• pp.47-53
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• 2007

In this study, we investigated the properties of incubation and growing of Pleurotus eryngii in addition to the mycological properties to use them as basic data for breeding. The speed of mycelial growth on the MCM was faster than on the PDA. The biomass in the PDB broth culture was higher than in the MCM and YMG broth culture. KNR2515 and KNR2516 required 19 days for growth of mycelia on commercial sawdust media. KNR2503 required 6.5 days and 15.3 days for pin-heading and harvesting, respectively. In morphological properties by the mushroom, the heights of KNR2312 and KNR2322 were 122.7 and 121.0 mm, respectively. The thickness of KNR2322 and KNR2513 were 39.8 mm and 31.3 mm, respectively. The weight of KNR2524's fruiting body was 36.3 g, which is good as wild strain. The quality of fruiting body of KNR2503 was 4.0 in comparison to the score 7 of commercially cultivated strains. KNR2512 had the darkest color of pileus with L value 43.6. The slow growing strains, KNR2511, KNR2513, and KNR2512 had the bright pileus with L value 80. In morphological characteristics, KNR2511, KNR2513, and KNR2515 had white lamellar and plane pileus. The three strains are supposed to be the same group and KNR2516 and KNR2518 appeared to be related to the group. The commercially cultivated strains had convex pileus, KNR2502, KNR2503, KNR2504, KNR2521, and KNR2525 had infundibuliform, and the other strains had plane pileus. Several strains were valuable for breeding, JNR2503 for growth rate, KNR2512 for pileus color, and KNR2312, KNR2322, KNR2503, and KNR2513 for the quality.