• Korean Journal of Breeding Science
• /
• v.40 no.1
• /
• pp.26-30
• /
• 2008

Normal soybean seed contains three lipoxygenase isozymes called L-1, L-2, and L-3, respectively, which are responsible for the generation of undesirable grassy-beany flavors. Simple and effective methods for the detection of lipoxygenase isozymes were developed in soybean seeds. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) has been tried in separating these isozymes. It was done effectively on 7.5% separating gel and 4.5% stacking gel. However, no reliable method has been developed specifically for separating L-3, L-13 and L-23. Visual judging methods were based on the bleaching activities of lipoxygenase in contact with methylene blue and ${\beta}$-carotene. Sodium linoleate bleaching method was adopted to determine L-1 and L-2. Carotene bleaching and spectrophotometric methods were used to determine L-3. These systems were very rapid within one minute, furthermore only required a small piece of cotyledon (below 10 mg) and the other part could be used for generation advance after analysis. It was demonstrated that 200 seed samples could be analyzed per day by one laboratory assistant. The combination of visual judging methods and electrophoresis is suitable for breeding programs. It took 6.5 hours for analysis of 100 seed samples by one person.

• The korean journal of orthodontics
• /
• v.29 no.6 s.77
• /
• pp.673-688
• /
• 1999

This study was conducted in order to analyze the mechanical characteristics of multiloop edgewise archwire (MEAW). The purposes were 1) to compare load deflection rate (LDR) of MEAW with that of various other arch wires in the individual interbracket span, 2) to compare the wire stiffness in the interbracket span with that in the multi-L-loop region (the span from distal border of the bracket of the lateral incisor to the mesial border of the buccal tube of the second molar), and 3) to verify the experimental results with theoretically derived formula. The single L-loops of five different horizontal lengths and multi-L-loops for the upper and lower arches were made out of .$016\times.022$ permachrome stainless steel wire. Straight segment of plain stainless steel, TMA and NiTi wire of the same dimension were prepared. The LDR was measured using Instron model 4466 with the load cell of 50N capacity at cross head speed of 1.0mm/min, and maximum deflection of 1.0mm. Five specimens were tested under each experimental condition. The wire stiffness number for each interbracket region and multi-L-loop region was calculated from the LDR and the interbracket spans. By dividing the theoretical model of multi-L-loop into 35 linear segments, the energy stored in each segment was obtained. Then the LDR and wire stiffness of single L-loop and multi-L-loop were calculated and compared. The findings were as follows : 1) The average LDR of MEAW in the individual interbracket region was 1/1.53 of that of the NiTi,1/2.47 of TMA and 1/5.16 of the plain stainless steel wire. 2) The wire stiffness of MEAW in the multi-L-loop region was 1.53 times larger than that in the interbracket region, and the LDR was almost twice as large as that of NiTi in that region. 3) According to the theoretically derived equation, the wire stiffness of the single L-loop was lower than that of multi-L-loop. The results of this study suggest that MEAW has the unique mechanical Property which could allow individual tooth movement and transmit elastic force effectively through the entire arch wire.

• Korean Journal of Environmental Biology
• /
• v.21 no.3
• /
• pp.286-291
• /
• 2003

We investigated the effects of molting-hormone insecticide tebufenozide on D7 (the day of hatching from egg) larvae of the midge Chironomus riparius in growth developments. D7 instar larvae were exposed test concentrations were chosen control, 10${\mu}g \;L^{-1}$, 30${\mu}g \;L^{-1}$, 60${\mu}g \;L^{-1}$ and 100${\mu}g \;L^{-1}$ of tebufenozide. In general, dead larvae showed 16% on the next day after insecticide treatments (D12), and observed 44% from D12 to D16 in this exposed days. Dead larvae of C. riparius was abruptly increased on D12 and also continuously increased along the days in 10${\mu}g \;L^{-1}$ treatments. The converged day was from D12 to D16 at move 30${\mu}g \;L^{-1}$ treatments in this study. Therefore, dead larvae obviously increased along these concentrations of tebufenozide. In control condition,78% of the test individuals have grown the pupae. But the larvae have developed the pupa stage from 5% to 17% of the test organism in 10${\mu}g \;L^{-1}$ and 30${\mu}g \;L^{-1}$ treatments. And 75% of the test individuals was arrived the adult through the molting process in control condition. While the other condition was rarely observed the adult. Usually, the emerged period of the test individuals was gathered the D26-D29 in control. The dead pupa showed from D19 to D20 in 30${\mu}g \;L^{-1}$ treatments, D32 in control and D33 in 10${\mu}g \;L^{-1}$ treatments. The observed periods of dead pupa were D32-D34 in control and D33-D37 in 10${\mu}g \;L^{-1}$ treatments. Consequently, due to molting hormone disruption, development of midge was postponed relatively low concentration such as 10 treatments of tebufenozide.

• Horticultural Science & Technology
• /
• v.28 no.5
• /
• pp.790-795
• /
• 2010

This experiment was conducted to clarify the effects of cycloheximide and holding solution on vase life of cut 'Blue Magic' iris. The vase life of iris flowers held in 3% sucrose (S) + $100mg{\cdot}L^{-1}$ hydroxy quinoline sulfate (HQS) + $50mg{\cdot}L^{-1}$ $AgNO_3$ + $100mg{\cdot}L^{-1}$ Benzylaminopurine (BA), 3% S + $100mg{\cdot}L^{-1}$ HQS + $10{\mu}M$ cycloheximide (CHI), or 3% S + $100mg{\cdot}L^{-1}$ HQS + $50{\mu}M$ CHI were much longer than those held in distilled water. Squeeze stem phenomenon that showed at a holding solution containing $200mg{\cdot}L^{-1}$ HQS disappeared at a holding solution containing $100mg{\cdot}L^{-1}$ HQS. The holding solution containing 3% S + $100mg{\cdot}L^{-1}$ HQS + $50mg{\cdot}L^{-1}$ $AgNO_3$ + $100mg{\cdot}L^{-1}$ BA extended the most effective treatments on vase life, fresh weight, water balance, and flowering of cut iris flowers. However, the holding solution containing 3% S + $100mg{\cdot}L^{-1}$ HQS + $10{\mu}M$ CHI and 3% S + $100mg{\cdot}L^{-1}$ HQS + $50{\mu}M$ CHI was not effective in solution uptake or transpiration, but did result in high water balance. Iris flowers treated with CHI at the half-open flower stage showed increases in ornamental value, such as full flower opening and extended vase life. To improve flower quality and prolonging vase life of cut iris flowers, a holding solution containing $50{\mu}M$ CHI can be used continuously from the half-open stage.

• English Language & Literature Teaching
• /
• v.10 no.2
• /
• pp.1-23
• /
• 2004

This article reports a bi-directional interlanguage study designed to investigate the initial state of L2 acquisition with regard to English and Korean wh-questions. Based on the UG system in line with the minimalist theory, it was hypothesized that the L2 initial state is characterized by the most economical form of syntax in which no overt wh-movement to Spec-CP is assumed. Results of the early interlanguage study showed that 1) L1 Korean learners of L2 English predominantly produced wh-questions with the fronted wh-word, but without productive wh-movement to the Spec-CP position; and 2) L1 English learners of L2 Korean overwhelmingly produced wh-questions with the wh-word remaining in-situ. These results were interpreted as supporting the minimalist account of the L2 initial grammar in that no overt syntactic wh-movement were adopted in early interlanguages of both English and Korean regardless of the learner's L1.

• Journal of applied mathematics & informatics
• /
• v.30 no.1_2
• /
• pp.27-47
• /
• 2012

It has become apparent from the recent work by Choi et al. [3] on the nonlinear beam deflection problem, that analysis of the integral operator $\mathcal{K}$ arising from the beam deflection equation on linear elastic foundation is important. Motivated by this observation, we perform investigations on the eigenstructure of the linear integral operator $\mathcal{K}_l$ which is a restriction of $\mathcal{K}$ on the finite interval [$-l,l$]. We derive a linear fourth-order boundary value problem which is a necessary and sufficient condition for being an eigenfunction of $\mathcal{K}_l$. Using this equivalent condition, we show that all the nontrivial eigenvalues of $\mathcal{K}l$ are in the interval (0, 1/$k$), where $k$ is the spring constant of the given elastic foundation. This implies that, as a linear operator from $L^2[-l,l]$ to $L^2[-l,l]$, $\mathcal{K}_l$ is positive and contractive in dimension-free context.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.9 no.6
• /
• pp.1733-1738
• /
• 2008

The treatment efficiency of rotating biological contactors (RBCs) for the high strength of dairy wastewater was investigated. Two different systems were conducted composing of a single RBC with tapered aeration reactors for the system A and a sequential RBCs following tapered aeration reactors for the system B. Experiments using dairy wastewater were conducted for 50 days period of time, in which hydraulic rates were maintained at the constant ratios of 346L per day and variable BOD concentrations were at the range from 1,358mg/L to 829mg/L, the $COD_{cr}$, concentration of the range were from 2,384mg/L to 1,329mg/L, the range of T-N concentrations was from 66mg/L to 38mg/L, and 50% of internal recycle and 50% of sludge return were performed. Results indicated that the removal efficiencies of the system B were higher than those of the system A. The removal efficiencies of system A for the BOD, $COD_{cr}$, T-N and T-P were 97.8%, 96.7%, 87.2% and 82%, respectively. The removal efficiencies of system B for the BOD, $COD_{cr}$, T-N and T-P were as of 98.5%, 98.5%, 91.3% and 89%.

• Korean Journal of Plant Tissue Culture
• /
• v.22 no.1
• /
• pp.41-46
• /
• 1995

Leaf mesophyll protoplasts of Dianthus superbus were cultured in MSP1 liquid medium supplemented with 0.5 mg/L BAP, 2.0 mg/L NAA and 9% mannitol. Protoplast-derived colonies were formed after 3 to 4 weeks of culture in the dark at 27$^{\circ}C$. These colonies were kept under continuous illumination (21.5 $\mu$E. m-2 sec-1) for 2 weeks and finally most of the colonies became green microcalli, about 3 mm in diameter. When green microcalli were transferred to MS solidified medium with 2.0 mg/L 2,4-D, they formed embryogenic calli after 4 week of culture. These calli were then transferred onto $N_{6}$ medium containing 0.1mg/L 2,4-D, 0.1 mg/L NAA, 2.0 mg/L kinetin and 2.0 g/L casein hydrolysate and cultured under illumination. After 5 weeks of culture the calli gave rise to multiple shoots of 10 to 15 per callus. Upon transfer onto MS medium containing 2.0 mg/L NAA, they were noted. The regenerates were successfully transplanted into potting soil.

• KSBB Journal
• /
• v.14 no.5
• /
• pp.628-632
• /
• 1999

Optimization of the medium and fermentation conditions for erythritol production has been studied. We have found that the optimal carbon source was glucose at the concentration of 400 g/L. The optimal temperature was 3$0^{\circ}C$ with excessive aeration. Improved erythritol productivity was achieved by reducing the yeast extract from 5 g/L to 3g/L while adding 2.7 g/L urea, 1.79g/L $K_2HPO_4, and 0.18g/L MgSO$_4$. 7$H_2O. The erythritol productivity increased from 0.747 g/L/h to 1.071 g/L/h and the yield increased from 31.4% to 45.2%. The byproduct glycerol was reduced from 96.6g/L to 45.7g/L as well. We have performed 5L fermentation with and without the pH control. The erythritol productivity with the pH control was about 30% lower than that without pH control. Excessive foaming of 5L fermentation has been observed during fermentation.

• Asian-Australasian Journal of Animal Sciences
• /
• v.12 no.5
• /
• pp.799-805
• /
• 1999

This study was conducted to investigate the effects of L-carnitine with different levels of lysine on performance of pigs weaned at 21 days of age. A total of 120 pigs were allotted into a $3{\times}2$ factorial design with three different levels of lysine (1.40%, 1,60% and 1.80%) and two levels of L-carnitine (0 and 1,000 ppm). Each treatment had 4 replications with 5 pigs per replicate. Pigs of $22{\pm}1$ days (5.9 kg of body weight) were grouped into a completely randomized block design. Treatments were 1) 1.4-Crt; 1.40% of lysine with 1,000 ppm of L-carnitine, 2) 1.4-N; 1.40% of lysine without L-carnitine, 3) 1.6-Crt; 1.60% of lysine with 1,000 ppm of L-carnitine, 4) 1.6-N; 1.60% of lysine without L-carnitine, 5) 1.8-Crt; 1.80% of lysine with 1,000 ppm of L-carnitine and 6) 1.8-N; 1.80% of lysine without L-carnitine. Growth performance was optimized in pigs fed 1.6% lysine regardless of carnitine addition. For the first 7 days of the experimental period, the best ADG and F/G were found in pigs within the 1.6-Crt group. Carnitine significantly improved (p<0.05) ADG of pigs when the lysine level in the diet was 1.6%. Only in the third week carnitine had a significant influence on growth performance of pigs. A lysine-sparing effect of L-carnitine was not detected in this study. The 1.6-Crt group showed the best proximate nutrient digestibility, and the crude fat and gross energy digestibility were higher when the L-carnitine was added in the diet. Lysine level significantly affected the digestibilities of DM (p<0.001), GE (p<0.001), CP (p<0.01) and C.fat (p<0.05). Carnitine also significantly improved digestibility of nutrients. Lysine level as well as carnitine level affected the amino acids digestibility, however, in 1.8% lysine diet carnitine did not influence on amino acids digestibility. Plasma carnitine content was significant higher (p<0.05) in pigs fed L-carnitine. This indicates the increased biological availability of carnitine within the body. L-carnitine supplementation tended to improve feed utilization during the third week (p<0.10) and during the entire period (p=0.10). Lysine level significantly affected feed utilization of pigs during the third week and entire period (p<0.05). As pigs grew, the lysine requirement was reduced.