• Korean Journal of Materials Research
• /
• v.11 no.4
• /
• pp.283-289
• /
• 2001

Composite cathodes of 50/50 vol% LSM- YSZ (La$_{1-x}$Sr$_{x}$MnO$_3$-yttria stabilized zirconia) were deposited onto surface- Polished YSZ electrolytes by colloidal deposition technique. The cathode characteristics were then examined by scanning electron microscopy (SEM) and X-ray diffraction (XRD) and studied by ac impedance spectroscopy (IS). The typical impedance spectra measured for an air/LSM- YSZ/YSZ/Pt/air cell at $700^{\circ}C$ were composed of two depressed arcs. Addition of YSZ to the LSM electrode significantly enlarged the triple-phase boundaries (TPB) length inside the electrode, which led to a pronounced decrease in cathodic resistivity of LSM-YSZ composite electrodes. Polishing the electrolyte surface to eliminate the influences of surface impurities and to enlarge the TPB length can further reduce cathode resistivity. The cathodic resistivity of the LSM- YSZ electrodes was a strong function of operation temperature, composition and particle size of cathode materials, applied current, and electrolyte surface roughness.

• Plant Biotechnology Reports
• /
• v.3 no.4
• /
• pp.277-283
• /
• 2009

One of the limitations to conducting maize Agrobacterium-mediated transformation using explants of immature zygotic embryos routinely is the availability of the explants. To produce immature embryos routinely and continuously requires a well-equipped greenhouse and laborious artificial pollination. To overcome this limitation, an Agrobacterium-mediated transformation system using explants of type II embryogenic calli was developed. Once the type II embryogenic calli are produced, they can be subcultured and/or proliferated conveniently. The objectives of this study were to demonstrate a stable Agrobacterium-mediated transformation of maize using explants of type II embryonic calli and to evaluate the efficiency of the protocol in order to develop herbicide-resistant maize. The type II embryogenic calli were inoculated with Agrobacterium tumefaciens strain C58C1 carrying binary vector pTF102, and then were subsequently cultured on the following media: co-cultivation medium for 1 day, delay medium for 7 days, selection medium for $4{\times}14$ days, regeneration medium, and finally on germination medium. The T-DNA of the vector carried two cassettes (Ubi promoter-EPSPs ORF-nos and 35S promoter-bar ORF-nos). The EPSPs conferred resistance to glyphosate and bar conferred resistance to phosphinothricin. The confirmation of stable transformation and the efficiency of transformation was based on the resistance to phosphinothricin indicated by the growth of putative transgenic calli on selection medium amended with $4mg\;1^{-1}$ phosphinothricin, northern blot analysis of bar gene, and leaf painting assay for detection of bar gene-based herbicide resistance. Northern blot analysis and leaf painting assay confirmed the expression of bar transgenes in the $R_1$ generation. The average transformation efficiency was 0.60%. Based on northern blot analysis and leaf painting assay, line 31 was selected as an elite line of maize resistant to herbicide.

• Asian-Australasian Journal of Animal Sciences
• /
• v.27 no.2
• /
• pp.278-283
• /
• 2014

Cecropins (Cec) are antibacterial peptides and their expression is induced in a pig intestinal parasite Ascaris suum by bacterial infection. To explore the usefulness of its activity as an antibiotic, CecP4 cDNA was prepared and cloned into the pPICZ B expression vector and followed by the integration into AOX1 locus in Pichia pastoris. The supernatants from cell culture were collected after methanol induction and concentrated for the test of antimicrobial activity. The recombinant P. patoris having CecP4 showed antimicrobial activity when tested against Staphyllococcus aureus in disc diffusion assay. We selected one of the CecP4 clones (CecP4-2) and performed further studies with it. The growth of recombinant P. pastoris was optimized using various concentration of methanol, and it was found that 2% methanol in the culture induced more antibacterial activity, compared to 1% methanol. We extended the test of antimicrobial activity by applying the concentrated supernatant of CecP4 culture to Pseudomonas aeruginosa and E. coli respectively. Recombinant CecP4 also showed antimicrobial activity against both Pseudomona and E. coli, suggesting the broad spectrum of its antimicrobial activity. After improvements for the scale-up, it will be feasible to use recombinant CecP4 for supplementation to the feed to control microbial infections in young animals, such as piglets.

• Journal of the Korean Society of Food Culture
• /
• v.18 no.5
• /
• pp.418-427
• /
• 2003

This study was performed to investigate the relationships among personality preferences, dietary habit and nutrient intake of University students (n=283). Mean dietary habit score was similar between sexes and was 46.1/100 in male students and 45.1/100 in female students. Average energy intake of male students was 2,019 kcal (80.8% of RDA) and that of female students was 1,675 kcal (83.7%). Male students were taking less than 90% of RDA in calcium and vitamin $B_2$ and female students were taking less than 90% of RDA in calcium, iron, vitamin C, and vitamin A. Students preferring Judgment had significantly higher dietary habit score than students preferring Perception. Extraversion had higher nutrient intake than Introversion both in male and female students. Male students preferring Feeling had also higher nutrient intake than students preferring Thinking. Nutrient density per 1,000 kcal was higher in Thinking and Judgment than Feeling and Perception. In conclusion, students preferring Judgment and Extraversion have better dietary habit and nutrient intake than those preferring Perception and Introversion. More studies are necessary between personality preferences and dietary behavior to contribute to effective nutrition education and counseling.

• Korean Journal of Health Education and Promotion
• /
• v.21 no.1
• /
• pp.259-283
• /
• 2004

This is an quasi experimental study using nonequivalent pre-test post-test control design for the development of the CAI program and an analysis of its effects, for nursing college students to learn emergency patient triage. This program was developed from November, 2000 to middle of September, 2001 with the aid of curriculum design experts. The subjects of this study were 86 randomly sampled freshmen students of C nursing college in Ulsan. They were divided into 45 for the test group and 41 for the control group. The CAI program for the learning of the emergency patient triage has been developed on the basis of Merrill's Component display theory and Keller's ARCS theory and through the curriculum design process of Hannafin ＆ Peck. It has also been done with the use of Tool book 8.0, the multimedia righting tool. The experiment to verify the effect of the CAI program has been carried on from September, 20 to October, 8 2001. There were six hypotheses to accomplish the purpose of the study, and the analysis of the data was done with the use of SPSS/win program. As a result of this study, the author concluded that this CAI program is an effective mediation method to promote the learning accomplishment and learning motive for nursing college students. Therefore in the field of emergency nursing education, it would be possible to use this program as means for widening the possibility of self-learning and to promote individual learning of nursing college students.

• The Korean Journal of Ecology
• /
• v.20 no.4
• /
• pp.275-283
• /
• 1997

Vertical and temporal characteristics of desalinized reclaimed soil were analyzed from reclaimed coastal land on the western coast of Korea. Of the vertical changes during desalting, pH valuse were the lowest at the topsoil without regard to reclaimation time. The content of C1 were designated as the early period (the first 2-4 years) which decreased exponentially and the later period(the last 5-7 years) which was almost constant, from top to down. In temporal changes of the soil attributes, pH values increased for 5 years and decreased at 6 year after reclamation. Chlorine leaches more rapidly than Na does, K and Ca are constant but Mg increases as time elapsed after reclamation. Sometimes the content of Ca and K in the reclaimed soil are of higher concentration than that of the seawater after reclamation. During desallinization as exemplified by decreasing EC of the soil, Cl and Na are rapidly leached, but K, Ca and Mg are somewhat enhanced. The ration of Na/Cl in the soil equals 1 when the EC registers 5 mmho and then increases dramatically as the EC decreases. Rapid leaching of $Cl^{-}$ elicits an increasing pH valus. The electrostatic balance of the soil is achived by replacement of $Cl^{-}$ with $OH^{-}$ until stationary or until a decreasing pH value is reached again.

• Journal of Microbiology and Biotechnology
• /
• v.29 no.2
• /
• pp.283-291
• /
• 2019

Fermentation of food waste in the presence of different concentrations of salt ($Na^+$) and ammonia was conducted to investigate the interrelation of $Na^+$ and ammonia content in bio-hydrogen production. Analysis of the experimental results showed that peak hydrogen production differed according to the ammonia and $Na^+$ concentration. The peak hydrogen production levels achieved were (97.60, 91.94, and 49.31) ml/g COD at (291.41, 768.75, and 1,037.89) mg-N/L of ammonia and (600, 1,000, and 4,000) $mg-Na^+/L$ of salt concentration, respectively. At peak hydrogen production, the ammonia concentration increased along with increasing salt concentration in the medium. This means that for peak hydrogen production, the C/N ratio decreased with increasing salt content in the medium. The butyrate/acetate (B/A) ratio was higher in proportion to the bio-hydrogen production (r-square: 0.71, p-value: 0.0006). Different concentrations of $Na^+$ and ammonia in the medium also produced diverse microbial communities. Klebsiella sp., Enterobacter sp., and Clostridium sp. were predominant with high bio-hydrogen production, while Lactococcus sp. was found with low bio-hydrogen production.

• Fisheries and Aquatic Sciences
• /
• v.27 no.5
• /
• pp.283-293
• /
• 2024

Mahseer (Tor soro) growth performance tends to be slow, necessitating further development and intensification of cultivation. One way to develop aquaculture intensification is to manipulate cultivation containers to create optimal environmental conditions for the mahseer to grow. This study aimed to examine the body performance and growth performance of mahseer reared in different colored containers. Experimental research with completely randomized design was employed, with four colored container treatments namely treatment A (transparent), B (green), C (blue), and D (black), with four replications in each treatment. Findings indicate that different rearing media colors had significant effect on absolute length (4.68 ± 0.24 cm), absolute weight (1.58 ± 0.35 g), specific growth rate (2.17 ± 0.38%), feed conversion ratio (2.87 ± 0.04), survival rate (100 ± 0.00%), gross energy (3,816 ± 65.05 cal/g), and body proximate. Physiologically, mahseer fish bred using blue and black containers tend to be more resistant to stress.The best body performance and growth performance were observed in the blue and black colored containers.

• Korean Journal of Ichthyology
• /
• v.18 no.4
• /
• pp.283-292
• /
• 2006

Expressed sequence tag (EST) analysis was conducted using a complementary DNA (cDNA) library made from the kidney mRNA of olive flounder (Paralichthys olivaceus). In the survey of 390 ESTs chosen from the kidney cDNA library, 250 ESTs showed significant homology to previously described genes while 140 ESTs were unidentified or novel. Comparative analysis of the 250 identified ESTs showed that 14 (5.6%) clones were representing 11 unique genes identified as homologous to the previously reported olive flounder ESTs, 198 (79.2%) clones representing 160 unique genes were identified as orthologs of known genes from other organisms, and orthologs were established for 38 (15.2%) clones representing 37 genes of known sequences with unknown functions. We also identified several kinds of immune associated proteins, indicating EST as a powerful method for identifying immunerelated genes of fish as well as identifying novel genes. Further studies using cDNA microarrays are needed to identify the differentially expressed transcripts after disease infection.

• Journal of Life Science
• /
• v.17 no.1 s.81
• /
• pp.125-131
• /
• 2007

Amino acid and fatty acid compositions of the physiological activity substance in the seed and pulpy substance of feral peach (Prunus persica Batsch var. davidiana Max.) were analyzed for the use as an biohealth functional processed products. The proximate compositions in the vacuum freeze dried seed and pulpy substance of feral peach were carbohydrate 63.92% and 75.11%, crude protein 27.85% and 12.77%, moisture 3.61% and 4.69%, crude fat 1.21% and 4.80%, crude ash 3.41% and 2.63%, respectively. Total amino acid contents in the protein of feral peach seed were 3,444.35 mg%, and the major amino acids were aspartic acid(681.10 mg%), glutamic acid(495.48 mg%), alanine(283.66 mg%), serine(251.36 mg%), proline(229.80 mg%), lysine(192.31 mg%) and leucine(191.34 mg%), respectively. Total amino acid contents in the protein of feral peach pulpy substance were 1,064.02 mg%, and the major amino acids followed aspartic acid(250.15 mg%), glutamic acid(129. 63 mg%), lysine, proline, leucine, alanine and serine, in a decreasing order. The richest total amino acid content contained in feral peach seed and pulpy substance was aspartic acid, followed by glutamic acid. The amount of free amino acids of feral peach seed were 6,215.34 ms%, and the major free amino acids were glutamic acid(827.25 mg%), threonine, valine and $\beta-aminobutyric$ acid, respectively. Free amino acid contents of pulpy substance were 683.82 mg%, and the major free amino acids were glutamic acid(339.49 mg%), serine proline, alanine and $\gamma-amino-n-butyric$ acid. Especially, in the case of glutamic acid, it was highest. The compositions of major total fatty acid in the lipid feral peach (Prunus persica Batsch var. davidiana Max.) seed and pulpy sabstance were linoleic acid($C_{18:2}$, n-6) and linolenic acid($C_{18:3}$, n-3), particularly.