• The Plant Pathology Journal
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• v.30 no.1
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• pp.33-42
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• 2014

Nivalenol (NIV) and deoxynivalenol (DON) are predominant Fusarium-producing mycotoxins found in grains, which are mainly produced by Fusarium asiaticum and F. graminearum. NIV is found in most of cereals grown in Korea, but the genetic basis for NIV production by F. asiaticum has not been extensively explored. In this study, 12 genes belonging to the trichothecene biosynthetic gene cluster were compared at the transcriptional level between two NIV-producing F. asiaticum and four DON-producing F. graminearum strains. Chemical analysis revealed that time-course toxin production patterns over 14 days did not differ between NIV and DON strains, excluding F. asiaticum R308, which was a low NIV producer. Both quantitative real-time polymerase chain reaction and Northern analysis revealed that the majority of TRI gene transcripts peaked at day 2 in both NIV and DON producers, which is 2 days earlier than trichothecene accumulation in liquid medium. Comparison of the gene expression profiles identified an NIV-specific pattern in two transcription factor-encoding TRI genes (TRI6 and TRI10) and TRI101, which showed two gene expression peaks during both the early and late incubation periods. In addition, the amount of trichothecenes produced by both DON and NIV producers were correlated with the expression levels of TRI genes, regardless of the trichothecene chemotypes. Therefore, the reduced production of NIV by R308 compared to NIV or DON by the other strains may be attributable to the significantly lower expression levels of the TRI genes, which showed early expression patterns.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.55 no.8
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• pp.403-407
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• 2006

Standard capacitors, as like as Hamon resistor standards, of series connection/parallel connection ratio $10{\mu}F/1000{\mu}F\;and\;100{\mu}F/10000{\mu}F$ were fabricated for calibration of impedance bridges or analyzers with measuring ranges up to 1 F. The calculated correction terms to the ratio of one measured value in series connection to the value in parallel connection were evaluated to be $1.92{\times}10^{-7}$. These capacitors were designed to be used not only as 100:1 capacitance standards but also as single capacitors or decade capacitors with decade values at frequencies up to 1 kHz.

• Journal of Applied Biological Chemistry
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• v.60 no.4
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• pp.327-332
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• 2017

In this study, the whitening activity of Nymphoides indica extract in B16F10 cells were measured. Inhibition rate of tyrosinase from mushroom was 42% at $1,000{\mu}g/mL$. And inhibition of tyrosinase and melanin biosynthesis in B16F10 cells were 26 and 25% at $5{\mu}g/mL$, respectively. The expression levels of cAMP and protein kinase A (PKA), which are higher levels of melanin-related factors, were found to be decreased in a dose-dependent manner. In addition, the expression rate of protein and mRNA of tyrosinase, tyrosinase related protein 1 (TRP1), tyrosinase related protein 2 (TRP2) and microphthalmia associated transcription factor (MITF). In this study, it was confirmed that the N. indica extract effectively inhibited the activity of tyrosinase, TRP1, TRP2 and MITF as well as the activity of PKA by effectively inhibiting cAMP. Therefore, it was confirmed that the N. indica extract has high value as a functional material.

• The Plant Pathology Journal
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• v.29 no.4
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• pp.446-450
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• 2013

The ascomycete fungus Fusarium graminearum is a major causal agent for Fusarium head blight in cereals and produces mycotoxins such as trichothecenes and zearalenone. Isolation of the fungal strains from air or cereals can be hampered by various other airborne fungal pathogens and saprophytic fungi. In this study, we developed a selective medium specific to F. graminearum using toxoflavin produced by the bacterial pathogen Burkholderia glumae. F. graminearum was resistant to toxoflavin, while other fungi were sensitive to this toxin. Supplementing toxoflavin into medium enhanced the isolation of F. graminearum from rice grains by suppressing the growth of saprophytic fungal species. In addition, a medium with or without toxoflavin exposed to wheat fields for 1 h had 84% or 25%, respectively, of colonies identified as F. graminearum. This selection medium provides an efficient tool for isolating F. graminearum, and can be adopted by research groups working on genetics and disease forecasting.

• Current Optics and Photonics
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• v.7 no.4
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• pp.354-361
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• 2023

We present the optical design and experimental verification of resolving performance of a 3× long wavelength infrared (LWIR) zoom camera for drones. The effective focal length of the system varies from 24.5 mm at the wide angle position to 75.1 mm at the telephoto position. The design specifications of the system were derived from ground resolved distance (GRD) to recognize 3 m × 6 m target at a distance of 1 km, at the telephoto position. To satisfy the system requirement, the aperture (f-number) of the system is taken as F/1.6 and the final modulation transfer function (MTF) should be higher than 0.1 (10%). The measured MTF in the laboratory was 0.127 (12.7%), exceeds the system requirement. Outdoor targets were used to verify the comprehensive performance of the system. The system resolved 4-bar targets corresponding to the spatial resolution at the distance of 1 km, 1.4 km and 2 km.

• Korean Journal of Agricultural Science
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• v.23 no.2
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• pp.212-218
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• 1996

This study was conducted to investigate the effects of coculture for the development rate to morula/blastocyst stages of early porcine embryos, derived from oocytes matured and fertilized In vitro, with porcine cumulus cell monolayers(PCM) in the two different media, respectively. The rates of embryos developed to 2-, 4-, 8~16-cell and morula/blastocyst stage were 48.7, 40.5, 34.8 and 17.0% in Ham's F-10 with PCM, and 48.3, 35.6, 22.1, and 13.4% in TCM-HEPES with PCM, respectively. The above development rates to morula/blastocyst stages were significantly higher than those of the embryos cultured in the Ham's F-10 and TCM-HEPES without PCM(P<0.05). The in vitro development rates to the morula/blastocyst stage of I-cell embryos cultured in Ham's F-10 and TCM-HEPES without PCM were 0.0~1.0%. Especially, most of embryos were observed to arrest the development beyond 4-cell stages. As shown in the above results, the coculture of in vitro fertilized porcine embryos with PCM in the two different media enhanced the development of fertilized eggs to morula/blastocyst stages in vitro. However, we didn't find out any difference for the in vitro development to morula/blastocyst stages between Ham's F-10 and TCM-HEPES media.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.293-293
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• 2022

This study is to develop new wheat breeding material through wide hybridization with wild species harboring useful characteristics such as salt, heat, and drought tolerance. Leymus mollis, wild rye was used to improve wheat genetic quality. L. mollis, is a perennial plant harboring tolerance against salt, heat, and drought because L. mollis distributes on the seaside. The F₁ hybrids were produced by crossing between common wheat (Triticum aestivum L., Chinese Spring) and L. mollis. Genomic in situ hybridization revealed that the F₁ hybrids have L. mollis genome. For the evaluation of salt and drought tolerance, seeds from the F₂ were used. Under 2% NaCl solution, the F₃ wheat-Leymus addition plants with salt tolerance showed more tillering and longer roots than other F₃ plants without salt tolerance. Also, the F₃ plants with salt tolerance showed better shallow-rooted than other F₃ plants without salt tolerance. Finally, the F₃ plants with salt tolerance made seed-setting under 2% NaCl condition, but other F₃ plants without salt tolerance were not. Under drought conditions, the F₃ plants with drought tolerance showed longer culm and spike length than other F₃ plants without drought tolerance and even those of Chinese Spring under well-water conditions. We evaluated and selected the F₃ plants with salt or drought tolerance for generation advancement.

• Journal of Practical Agriculture & Fisheries Research
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• v.19 no.1
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• pp.25-38
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• 2017

More than 90 percent of domestic consumption of the lettuce occupied leaf lettuce, and the farmer preferred high yield, late bolting and stable expression of anthocyanins. So, this research focused on making resistant to disease, late bolting, and good expression of anthocyanin for lettuce. Based on these characteristic's parents, 11 crosses were created. So we advanced the generation and investigated each generation from F₁ to F₇. In this year, we selected 90 combination 221 lines which was F₂ 42 combination 137 lines, F₃ 4 combination 17 lines, F4 11 combination 27 lines, F₅ 7 combination 30 lines, F₆ 1 combination 2 lines, F₇ 3 combination 8 lines. Among the selected 17 lines, 5007, 5014, 6004, 6005, 6021, 6023, 7001, 7002, 7006, 7007, 7010, 7011, 7015, 7018, 7019, and 7021 which were late bolting and good expression of anthocyanins were investigated their yield. Finally, we selected 5 lines 7001, 7002, 7011, 7018 and 7022 in this year.

• Korean Journal of Food Science and Technology
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• v.10 no.2
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• pp.224-230
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• 1978

Heat resistant putrefactive microorganisms causing spoilage of canned and processed foods were surveyed in the compost on mushroom growing bed, casing soil, raw mushrooms and canned products before sterilization at canneries located at 8 places including Buyo in Chung-Cheung-Do and monitored the total count and spore formers from the sample taken. The 9 strains of most severe heat resistant among the selected 140 spore formers were selected and determined D and Z value by TDT method. The most strong heat resistant strain was No. F-10, facultative thermophile, which was isolated from raw mushroom in Buyo area and it's Z value was $21.1^{\circ}F$ (M/15 phosphate buffer solution) and $D^{250}$ was 6.6 min.

• Journal of the Korean Solar Energy Society
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• v.40 no.1
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• pp.49-60
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• 2020

This study reviewed selected specific windows and reviewed the window performance certification criteria including KS F 2278 and KS L 9107 and analyzed the change in performance based on the change of area. This study also compared the heating and cooling loads of an apartment house applied with window performance reviewed in consideration of insulation and SHGC performance and actual size based on KS F 2278. The analyzed window was a double window composed of aluminum and PVC and the building was the apartment house model of 141 ㎡. The analysis results were as follows. First, as the window glass's thermal performance is superior to frame, the performance degraded in reduced area. In case of selected window, the 1 m × 1m window's thermal performance and SHGC decreased by 35% and 37% respectively compared to 2 m × 2 m window. Secondly, in the comparison of performance for increasing area with 2 m × 2 m and 3 m × 3 m windows, the 3 m × 3 m window's thermal performance and SHCG increased about 14%. Third, in the comparison of heating and cooling loads of the analyzed model considering the apartment house model applied with window performance derived from KS F 2278 and actual figures, the model's total heating and cooling loads increased by 33% with cooling decreasing by 36% and heating increasing by 77%. Above analysis results show that evaluation of window performance based on criteria such as KS F 2278 and KS L 9107 may lead to distortion of performances different from actual products. Thus, it is necessary to suggest new evaluation criteria.