• Korean Journal of Medicinal Crop Science
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• v.4 no.2
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• pp.119-125
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• 1996

To improve the efficiency of mass propagation in vitro of Fritillaria thunbergii, bulb scale and nodes were cultured in LS medium supplemented with the combination of 2, 4-D and kinetin or NAA and BA. The number and size of bulb, the number of adventitious shoot, the ratio of callus formation, rooting, and the effects of light and dark on the culture, plant regeneration from calli, and the gelling substances were investigated. The combination of 2, 4-D and kinetin in media was more effective than the media of NAA and BA for the bulblet formation. The media supplemented with 2 mg/L 2, 4-D and 1 mg/L kinetin, $1{\sim}2\;mg/L$ 2, 4-D without kinetin and $1{\sim}3\;mg/L$ BAA only were effective in the adventitious shoot development. Callus formation and root formation, respectively were effective in the medium supplemented with 2mg/L 2, 4-D and 1mg/L kinetin. In bulb formation, the medium with 5 mg/L kinetin was effective, and the most of bulbs were formed from the axillary bud of node part. In bulb formation, shoot growth, callus and root formation, the light culture for 16 hours per day was better than that in the dark culture. Bulb was nicely formed in the medium with 0. 2 mg/L 2, 4-D, 1 mg/L kinetin. The medium without hormone was most effective for plant regeneration. The phytagel was more effective than agar in the medium as the gelling agent.

• Journal of The Korean Association For Science Education
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• v.22 no.1
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• pp.12-21
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• 2002

The purpose of this study is to understand middle school students' levels of cognitive conflict for the students provided quantitative demonstration and qualitative demonstration after the pre-test. 297 middle school students were selected from one school in Pusan. Action-reaction problem of mechanics and electric bulbs in parallel problem of electricity were used in the demonstration and the pre-test. Students' cognitive conflict levels were investigated using the developed items by Kwon(1999) et al. We compared cognitive conflict levels between quantitative demonstration group and qualitative demonstration group. In addition to, we compared cognitive conflict levels between students who changed their preconceptions and the students who adhered to their preconceptions. We investigated correlation between levels of faith with preconceptions and cognitive conflict levels. The study generated the following results. First, students who selected incorrect choice in pre-test showed the higher levels of cognitive conflict in quantitative demonstration group than qualitative demonstration group and students who selected correct choice in pre-test showed higher levels of cognitive conflict in qualitative demonstration group than quantitative demonstration group. Second, students who changed their preconceptions were higher levels of cognitive conflict than students who adhered their preconceptions. Third, students who selected incorrect choice in pre-test showed positive correlation between levels of faith with preconceptions and levels of cognitive conflict, and students who selected incorrect choice in pre-test showed negative correlation between levels of faith with preconceptions and levels of cognitive conflict.

• Korean Journal of Organic Agriculture
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• v.23 no.2
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• pp.347-357
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• 2015

This experiment was conducted to test the efficiency of environmentally friendly materials for controlling garlic leaf blight by Stemphylium botryosum. Fifty five kinds of environmental friendly control agents are obtained from commercial market and are tested for spore germination using 96 well plate and among them, five agents (copper-, sulfur-, medinal herb extract-, sulfur+sodium bicarbonate- and oligo chitosan based compound) are selected for field test from 2012 and 2013 year. With reference of 2012 year test result, copper and oligo chitosan based compounds are chosen as 2013 year test. When the first symptoms were appeared early May season and environmental friendly control agents are applied as prompt as possible, the control value of copper and oligo chitosan based agents are 54% and 90% respectively as compared to the occasion of chemical agent Antracol WP (propineb 70%) and yield of bulbs are increased by 16% and 34% against untreated control and marketable garlic bulb yield were 79% and 95% against Antracol WP treatment, respectively. From this result, oligo chitosan based compound can be a good organic control agent candidate for garlic leaf blight disease in organic garlic cultivation.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.11
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• pp.1510-1518
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• 2010

The study was conducted to evaluate the effect of lighting schedule and nutrient density on growth performance, carcass traits and meat quality of broiler chickens. A total of 576 day old Arbor Acre male chickens was used with a $4{\times}2$ factorial arrangement. The four lighting schedules were continuous (23 L:1 D, CL), 20 L:4 D (12 L:2 D:8 L:2 D), 16 L:8 D (12 L:3 D:2 L:3 D: 2 L:2 D) and 12 L:12 D (9 L:3 D:1 L:3 D:1 L:3 D:1 L:3 D) and provided by incandescent bulbs. The two nutrient densities were high (H, starter diet: 13.39 MJ/kg apparent metabolisable energy (AME), 23.00% crude protein (CP); finisher diet: 13.39 MJ AME/kg, 19.70% CP) and low energy and protein level (L, starter diet: 12.03 MJ AME/kg, 20.80% CP; finisher diet: 12.14 MJ AME/kg, 18.30% CP). Houses with dark curtains and solid sidewalls were used. Chickens were randomly allocated to the 8 treatments with each treatment comprising 6 replicates of 12 chickens. Feed and water were available ad libitum. Lighting schedules showed no difference (p>0.05) in growth performance at the end of the experiment. 12 L:12 D significantly reduced (p<0.05) the concentration of malondialdehyde (MDA) compared to 23 L:1 D treatment. Intermittent lighting (IL) schedules produced higher protein content (p<0.001) in breast meat. Birds on high density diets had higher body weight (BW), feed intake (FI) (p<0.001), and feed conversion ratio (FCR) (p<0.001) throughout the experiment with the exception of 36 to 42 d. High nutrient density increased (p<0.05) abdominal fat, decreased (p<0.05) the moisture loss of meat, and reduced percentage of wings and legs. There was a significant lighting schedule${\times}$diet interaction (p<0.001) on FCR for days 8 to 14 and 15 to 21. Results indicated that IL can give similar growth performance in comparison with CL, meanwhile with positive effects on meat quality by increasing protein content and decreasing the concentration of MDA. High nutrient density resulted in greater growth performance.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.1
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• pp.1-13
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• 1980

The purpose of the present study is to find the light intensity which induces maximum gathering rate and to observe the variation of the gathering rate both in daytime and at night by using three species of commercial fishes: filefish, Stephanolepis cirrhifer (Temminck et Schlegel), conger eel, Astroconger myriaster (Brevoort) and crucian carp, Carassius oarassius (Linnaeus). An experimental tank $(360L\times50W\times55Hcm)$ was set up in a dark room. An illumination system was attached to one end of the tank to control horizontal, light intensity. Six artificial light sources were prepared by combination of two light bulbs (5W, 150W) and seven filters. During the experiment water depth was maintained 50 cm level in the tank. The tank was marked into six longitudinal sections each being 60 cm long to observe the distribution of fish. The fish were acclimatized in dark condition for 40 minutes prior to the main experiment. Upon turning on the light, the number of fish .in each section was counted 40 times every 30 seconds, and the gathering rates were obtain from the average number of fish in each section. In filefish the light intensity inducing maximum gathering rate was 0.7 lx(0.5-1.1 lx), and there nab little difference between day and night. Gathering rate varied propotionally to the length of illumination time. In conger eel the light intensities inducing maximum gathering rate were 1.9 lx(1.2-2.9 lx) in daytime and 5.2 lx (3.2-7.7 lx) at night. Thus, there was a considerable difference between day and night, but the gathering rate remained almost unchanged regardless to the length of illumination time. In crucian carp gathering rate did not show a definite pattern hut fluctuated irregularly. The gathering rate, however, was slightly higher at 16.21 lx, and there was little difference between day and night.

• Research in Plant Disease
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• v.18 no.3
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• pp.240-244
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• 2012

Burkholderia gladioli pv. alliicola CH1 showed typical soft rot symptoms at higher than $20^{\circ}C$ but very weak soft rot symptoms at temperature under $10^{\circ}C$. Among the nine agro-chemicals, oxolinic acid WP, streptomycin + copper hydroxide WP and streptomycin WP were found to be effective for the inhibition of the pathogen in vitro. The results of scanning electron microscopic investigation showed that onion bulbs was macerated by infection of B. gladioli pv. alliicola CH1. B. gladioli pv. alliicola CH1 was able to produce polygalacturonase but did not produce pectin lyase and carboxymethylcellulase. In analysis of the polygalacturonase activity of the isolated pectin-degradation enzymes from B. gladioli pv. alliicola CH1 total protein, three activity bands 45 kDa, 35 kDa, and 29 kDa were detected by the direct (or in-gel) activity staining on SDS-PAGE.

• Current Research on Agriculture and Life Sciences
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• v.17
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• pp.71-77
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• 1999

The study aimed to identify effect of shading rate and duration on the growth and flowering of Lilium species in faring culture. Plant height of 'Gelria' and 'Casablanca' increased by higher shading at early growth stage, whereas that of 'Jolanda' and 'Dream Land' decreased. Also, plant height of 3 cultivars except 'Gelria' were longer by higher shading at whole growth stage, that of 'Gelria' was shorter as compared to in untreated plants. In cultivar 'Gelria', blasting increased and days to flowering shorted in higher shading only except 100% shading treatment at early growth stage. In 100% shading treatment, Blasting of 'Jolanda' was occurred 15.7% and the number of flower buds of 'Dream Land' and 'Casablanca' were reduced. Flower buds of 'Gelria' were not induceded in continued shading condition regardless of shading degree, the number of flower buds and flower size of 'Jolanda' and 'Dream Land' was reduced by 75% and 50% shading, respectively and in 'Casablanca', days to flowering was longer by shading at whole growth stage. Growth of daughter bulbs in 'Gelria', 'Jolanda' and 'Dream Land' was not influenced by shading at early growth stage but those of 'Casablanca' was inactive. Whereas that of 4 cultivars were inactive in continused shading condition.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.9
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• pp.1299-1304
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• 2005

An experiment was conducted to study the production performance of broiler breeder females (25 to 40 weeks of age) fed either reference diet or low non-phytate phosphorus (NPP) diet with or without microbial phytase (500 FYT/kg) supplementation. A weighed (160 g/b/d) quantity of feed from each diet was offered daily to 40 replicates of one bird each housed in California type cage having individual feeders. Each cage was considered as a replicate. A continuous 16-h light per day was provided using incandescent bulbs. Body weight, egg production, egg weight, feed per egg mass, egg specific gravity, egg breaking strength, shell thickness, tibia ash and serum Ca and protein concentrations were not affected by reducing the NPP level from 0.30 to 0.18% in the broiler breeder diet. Supplementation of phytase (500 FYT/kg) enzyme to the diet containing 0.18% NPP had no added advantage on any of the above production parameters. The serum inorganic P was increased significantly (p<0.05) by either enhancing the NPP content from 0.18 to 0.30% or supplementing phytase @500 FYT/kg to the diet containing low P which were found comparable. Retention of Ca and P was positive on all the diets. P retention decreased significantly (p<0.05) with either increase in NPP content or phytase supplementation in the diet. Neither NPP nor phytase supplementation influenced bone mineralization in terms of tibia ash and strength. The hatchability was not influenced by either increasing the NPP content or supplementing the enzyme phytase. Similarly, the P concentration in the egg yolk and day old chick, day old and 14th day body weight and leg score was not altered by increasing the level of NPP or supplementing phytase enzyme. The mortality was within the normal limits in all the three dietary groups. Thus, it can be concluded that 0.18% NPP (288 mg NPP intake/b/d) in the broiler breeder' diet is adequate in sustaining the optimum performance from 25 to 40 wks of age. Enhancing the NPP content or supplementation of phytase (500 FYT/kg diet) to diet containing 0.18% NPP had no added advantage on performance.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.2
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• pp.187-194
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• 2009

The aim of this study was to investigate the physicochemical characteristics of native Korean Allium wakegi Araki samples, which were grown from seven local seed bulbs(Yesan, Muan, Anmyon-do, Deokjeok-do, Jeju-do, Yecheon, and China) to produce high quality native Korean Allium wakegi Araki. For the proximate composition of samples, moisture contents were in the range of 90.69~92.43%. The crude protein content of the Jeju-do sample was highest compared to the other samples. However, there were no significant differences in total sugar contents between samples. The seed bulb origin did not affect the hardness of the stem part, but was high for the leaves of the Yesan sample compared to the other samples. The results for anti-oxidative activity were as follows: Yesan(2.30 mg/mL) > China(2.51 mg/mL) > Muan (2.56 mg/mL) > Yecheon(2.74 mg/mL) > Jeju-do(2.85 mg/mL) > Anmyon-do(2.87 mg/mL) > Deokjeok-do(3.18 mg/mL). In terms of mineral and amino acid contents, the Yesan sample showed the highest levels, respectively, compared with the other samples. Food values such as contents of total phenolics and pyruvic acid were highest in the Jeju-do sample. These results show that the physicochemical characteristics of Allium wakegi Araki were significantly different according to different seed bulb origins.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.4
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• pp.637-642
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• 2010

Pre-treatment steps of fresh produce as Saengshik raw materials are followed by initial clean-up, dipping, primary washing, and cutting. Hypochlorous acid solution was applied in the dipping step to reduce natural microflora. Also, procedures were changed by cutting, dipping and then primary washing, and the efficacy of hypochlorus acid was evaluated. Potatoes, carrots, kales, and angelicas were submerged in water or 100 ppm of hypochlorous acid for 5 min. After initial clean-up, the aerobic plate counts of potatoes, carrots, kales and angelicas were 4.7, 5.3, 5.6, and 5.7 log CFU/g, respectively. When samples were submerged into water, it only reduced the population of natural microflora by 0.2 to 1.1 log CFU/g, whereas when treated with hypochlorous acid, it reduced the population by 0.5 to 2.8 log CFU/g. Reductions of natural microflora in green leafy vegetables were more highly achieved than bulbs such as potatoes and carrots. However, the numbers of natural microflora were increased after cutting step. To control the cross contamination at the cutting process, the process was changed as follows: initial clean-up, cutting, dipping in hypochlorous acid, and then primary washing. It showed effective reduction of the population by 2.3 to 3.2 log CFU/g. Hypochlorous acid solution could be useful as a sanitizer for surface washing of fresh vegetables.