• Korean Journal of Ichthyology
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• v.18 no.3
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• pp.251-265
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• 2006

To investigate the impingement of fish on the traveling screens, fishes were collected from the traveling screens at Hadong Power Plant through the year of 1999. A total of 84 fish species were collected during the study period. The dominant species were Leiognathus nuchalis, Engraulis japonicus, Trichiurus lepturus and Takifugu niphobles. These four species accounted for 78.2% of the total number of individuals and 52.0% of total biomass collected. The number of fish species, number of individuals, biomass and species diversity indices fluctuated with the seasons. The number of species and biomass were high in April and August, and the number of individuals was high in April and July. However, the number of fish species, number of individuals and biomass of fishes showed low values in winter.

• The Plant Pathology Journal
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• v.17 no.4
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• pp.227-230
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• 2001

Bioassay techniques using young leaves and roots were developed to screen resistance of Atractylis spp. against Phytophthora drechsleri. Among 638 plants collected from various regions of Korea from 1994 to 1996, 67 were pre-screened in fields naturally infested with P. drechsleri, which is the causal pathogen of rhizome rot of Atractylis. Among the pre-screened sources, 18 (ca. 26.8%) were highly resistant to the pathogen in leaf inoculation. In the root inoculation test, abundant sporangia were formed in susceptible plant roots, while only a few or no sporangia were produced on the roots which were found resistant in the leaf inoculation test. Among the selected resistant plants, A. japonica 96066 and 96104 were used to cross with another species, A. macrocephala 96362 that showed high yield with good quality of rhizome but susceptible to the pathogen. The F$_1$hybrids designated as HA03 turned out to be resistant to the pathogen, indicating that resistant gene(s) was inherited. Among intra-species hybrids of A. japonica, HA07 and HA09 were resistant to the pathogen in leaf inoculation and moderate in root inoculation. However, HA08 was susceptible in both inoculation tests. This result suggests that the parent material might be genetically heterogeneous. Further genetic study should be carried out to verify this phenomenon.

• Journal of Sensor Science and Technology
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• v.5 no.6
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• pp.7-14
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• 1996

In order to develop gas sensor operating at low temperature, thick film $Co_{3}O_{4}$ sensor was fabricated. $Co_{3}O_{4}$ powder was prepared by precipitation from cobalt nitrate solution and the powders containing ethylene glycol as a binder was screen-printed on alumina substrate. Characteristics of sensitivity, response time, and recovery were investigated in terms of binder content and heat treating conditions. The $Co_{3}O_{4}$ sensor contained 15% ethylene glycol and heat-treated at $300^{\circ}C$ for 24hr showed the highest sensitivity at the operating temperature of $250^{\circ}C$. Its sensitivity of 1.1 to 5000ppm butane gas was very high, as compared with $0.8{\sim}0.85$ at the operating temperature of $350{\sim}400^{\circ}C$ for a commercial $SnO_{2}$ gas sensor. It is found that response time was fast, but recovery was poor for the sensor.

• Korean Journal of Agricultural Science
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• v.39 no.4
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• pp.515-523
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• 2012

Recent development and enlargement of reclaimed lands along the sea shores required to explore alternatives to existing crops, which are suitable to grow well and to declare higher profits. The objectives of this study were to investigate yield-related parameters for development of new leafy vegetables, and to screen some candidates among New Zealand spinach genotypes which were collected in Korea. Initially all the collected genotypes were grown for 7 weeks in a greenhouse of the experiment field in Chungnam National University, and then transplanted into the field to measure morphological or physiological parameters (plant height, branch number, stem diameter, chlorophyll content, and maximum canopy diameter), and yield-related parameters (leaf number, leaf length, leaf width, fresh weight and dry weight). Those parameters were quantitatively measured at 1, 5 or 9 weeks after transplanting (WAT). Parameters exhibiting statistically significant difference among the accessions were plant height, branch number, maximum canopy diameter, chlorophyll content, and leaf length. In contrast to highly correlated parameters with fresh and dry weight obtained in salt-affected soil in the earlier report, fresh weight was correlated significantly with leaf length (r=0.72), leaf width (r=0.64), and canopy diameter(r=0.66), while dry weight was correlated significantly with plant height (r=0.46), leaf length (r=0.72), leaf width (r=0.73), fresh weight (r=0.79), chlorophyll content (r=0.47), and canopy diameter (r=0.87). Based on the significantly correlated with yield parameters, the candidate accessions which were ranked in top statistical groups include CNU06A01, CNU06A13, CNU06A26, CNU06A35, CNU06A38, and CNU06A55. In order to be cultivated in reclaimed lands, it is necessary to screen out salt tolerant accessions among the above high-yielding genotypes.

• Food Science of Animal Resources
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• v.37 no.2
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• pp.297-304
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• 2017

Animal-origin food products pose serious threat to public food safety due to high microbial loads. The microbial and radioactive contaminations in commercial cold duck meat products were evaluated. Ten different lots of commercial samples ($C_1-C_{10}$) were classified based on type and smoking process. All samples were highly contaminated (< 4-7 Log CFU/g) with total aerobic bacteria (TAB), yeasts and molds (Y&M), and 7 samples ($C_1-C_7$) were positive for coliforms. Furthermore, three samples were contaminated with Listeria monocytogenes ($C_4-C_6$) and one with Salmonella typhimurium ($C_6$). No radionuclides ($^{131}I$, $^{137}Cs$, and $^{134}Cs$) were detected in any sample. The results of DEFT (direct epifluorescent filter technique)/APC (aerobic plate count), employed to screen pre-pasteurization treatments of products, indicated that smoked samples were positive showing DEFT/APC ratios higher than 4. Notably, the samples showed a serious threat to microbial safety, thus were irradiated with electron-beam (e-beam). The $D_{10}$ values for S. typhimurium and L. monocytogenes were 0.65 and 0.42 kGy, respectively. E-beam application at 3 and 7 kGy resulted in reduction of initial TAB, Y&M, and coliform populations by 3 and 6 log cycles, respectively. Thus, e-beam was proven to be a good decontamination approach to improve the hygiene of cold duck meat.

• Preventive Nutrition and Food Science
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• v.8 no.4
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• pp.390-394
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• 2003

In the post-genome period, the technique for identifying gene expression has been progressed to high throughput screening. In the field of molecular nutrition, the use of screening techniques to clarify molecular function of specific nutrients would be very advantageous. In this study, we have evaluated Zn-regulated gene expression in Zn-deficient, homocystein-treated EA.hy926 cells, using cDNA microarray, which can be used to screen the expression of many genes simultaneously. The information obtained can be used for preliminary assessment of molecular and signaling events modulated by Zn under pro-atherogenic conditions. EA.hy926 cells derived from human umbilical vein endothelial cells were cultured in Zn-adequate (control, 15 $\mu$M Zn) or Zn-deficient (experimental, 0 $\mu$M Zn) Dulbecco's MEM media under high homocysteine level (100 $\mu$M) for 3 days of post-confluency. Cells were harvested and RNA was extracted. Total RNA was reverse-transcribed and the synthesized cDNA was labeled with Cy3 or Cy5. Fluorescent labeled cDNA probe was applied to microarray slides for hybridization, and the slide was then scanned using a fluorescence scanner. The expression of seven genes was found to be significantly decreased, and one significantly increased, in response to treatment of EA.hy926 cells with Zn-deficient medium, compared with Zn-supplemented medium. The upregulated genes were oncogenes and tumor suppressor genes, cell cycle-related genes and transporter genes. The down-regulated gene was RelB, a component of the NF-kappaB complex of transcription factors. The results of this study imply the effectiveness of cDNA microarray for expression profiling of a singly nutrient deficiency, namely Zn. Furthur study, using tailored-cDNA array and vascular endothelial cell lines, would be beneficial to clarify the molecular function of Zn in atherosclerosis, more in detail.

• Food Science and Preservation
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• v.15 no.1
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• pp.88-93
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• 2008

This paper focused on the detection of the genetically modified soybean (Glycine max L. MERRILL) samples to search for the speedy analysis methods. We have identified the PCR (polymerase chain reaction) assay with a newly developed technique called DHPLC (denaturing high performance liquid chromatography) to screen the GMO in soybean. The DHPLC is i1s ability to directly detection specific sequences of DNA by using column. With these characteristics. the DHPLC assay had the advantage of simplicity, rapidty could obtain result within 20 minutes. Whereas $15{\times}10^{-4}ng/{\mu}L$ concentration could be detected with the PCR analysis, $15{\times}10^{-5}ng/{\mu}L$ concentration could be detected with the DHPLC method. Therefore, DHPLC method was considered to be a simple, fast and sensitivity screening method rather than PCR analysis for GMO detection in soybean.

• Biomolecules & Therapeutics
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• v.5 no.2
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• pp.215-221
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• 1997

In an effort to screen new selective antitumor agents from the broth of soil microorganism, cytotoxicity oriented screening was performed against tumor cells and 3 compounds (Compound 1, 2 and 3) were isolated from Sreptomyces parvullus ISP 5048 and their chemical structures were determined. Among these compounds, Compound 2 showed the highest cytotoxicity against P388Dl and L1210. While the $IC_{50}$/ values of compound 2 against P388Dl and L1210 were 0.073$\mu$g/ml and 0.07$\mu$g/ml, respectively, and the $IC_{50}$/ value of Compound 3 was 0.17$\mu$g/ml against human lung cancer cells, A549, the cytotoxicity of Compound 2 and 3 against normal cell line, Vero E6 cell was about 4- and 8-fold lower than that of adriamycin. Based on the chemical analysis data, Compound 3 was octacosamicine A, a known antibiotic, which was reported by Dobasih et al. (1988). Taken together the results demonstrated that Compound 2 and Compound 3 has the possibility to be developed as antitumor agent because of its potent cytotoxicity as well as high selectivity against various cancer cell lines.

• Korean Journal of Medicinal Crop Science
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• v.7 no.1
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• pp.37-44
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• 1999

This study was conducted to screen antitumoral activity by in vitro bioassay method using 60 Korean medicinal and food plants extracted by 80% EtOH. Antitumor activity test was applied by the PKC(protein kinase C) and antibleb formation, PLC (Phospholipase C), and colorimetric tetrazolium assay (MTT assay) methods. Chenopodjum album and black Glycine max showed high antitumoral activity by 73.5% and 81.0%, respectively, against PKC by bleb-forming assay and PKC enzyme assay on human chronic leukemia K562 cell. Black Glycine max also showed 91.2% antitumoral activity in the PLC method and the lowest $IC_{50}$ $value(4.7{\mu}g/ml)$ by MTT method against P-338 cell line. In the effect of the concentration treatment on antitumoral test, the more concentration indicated the more activity value.

• Korean Journal of Optics and Photonics
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• v.17 no.3
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• pp.240-247
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• 2006

This paper discusses the optical system design for projection TV using LCOS type micro display, which provides the high resolution, slim depth, and a large screen of more than 60 inches. We analyzed the relationship between the illumination system, projection lens, color separation & recombination system, and micro display. From this quantitative analysis, the starting data for the optimum light engine was defined, and all optical systems were designed by an optimization process. Three RGB panels were proposed for a high luminence system, and the four prisms symmetrically located make equal optical path lengths for the RGB rays. This color separation & recombination system enables the a compact illumination system. Also, in order to the slim light engine with high resolution, the folded projection lens system was designed by inserting a mirror between projection lenses.