• Korean journal of applied entomology
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• v.51 no.4
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• pp.397-403
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• 2012

This study compared the Aphelinus varipes and Aphelinus asychis in terms of how they parasitized the cotton aphid, Aphis gossypii and green peach aphid, Myzus persicae. Host-feeding, parasitism, emergence, the proportion of females and development time were all studied at 15, 20, 25 and $30^{\circ}C$ in controlled climate cabinets. When A. gossypii were provided for the two aphid parasitoids, the number of aphids killed by host-feeding for A. varipes (5.4 and 9.7 aphids) at $15^{\circ}C$ and $25^{\circ}C$ was higher than those for A. asychis (2.0 and 2.9 aphids). At $15^{\circ}C$ and $30^{\circ}C$, the parasitized A. gossypii were higher in A. varipes (11.1 and 21 aphids) than in A. asychis (7 and 12.3 aphids). The emergence rate was also significantly different between A. varipes (83.3%) and A. asychis (69.4%). The proportion of females was higher for A. asychis (75.2 and 73.9%) than for A. varipes (19.5 and 48.6%) at $15^{\circ}C$ and $30^{\circ}C$, respectively. No significant differences were found in development time between the two parasitoids. When M. persicae were provided for the two parasitoid species, the host-feeding number and the emergence rate of two parasitoids were not different at all four temperatures. The M. persicae were more highly parasitized by A. varipes (12.1 and 17.1 aphids) than by A. asychis (6.1, 10 aphids) at 20 and $25^{\circ}C$. The proportion of females for A. varipes (65.3 and 90.0%) was higher than that for A. asychis (34.4 and 78.8%) at $15^{\circ}C$ and $25^{\circ}C$. The development time from oviposition to the adult emergence of A. varipes (19.9 d) was significantly longer than that of A. asychis (16.5 d) at $20^{\circ}C$. Development times decreased with increasing temperature for both in two parasitoid species.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.4
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• pp.336-343
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• 2019

Wet direct-seeding (WDS) is an important method for improving the competitiveness of rice production in South Korea. We analyzed the optimum direct-seeding date to establish the rice standing rate in each area and selected suitable areas for WHS by considering the heading stage limit date for improving cultivation safety. As a result, the rice direct-seeding date to control weedy rice was around 5.15, 5.17-5.19, and after 5.20 in southern Youngnam, southern Honam, and the Middle Coast areas, respectively. However, the optimum seeding date for good standing rice was in late March in most areas. Analyzing by area, most of the southern plains and parts of the central inland plain are suitable for WHS. However, most parts of Gwangwon-do, and the northern parts of Chungbuk, Gyeongbuk, and Yeonghonam areas are not suitable for WHS, and should therefore avoid WHS.

• Journal of agriculture & life science
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• v.45 no.1
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• pp.101-107
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• 2011

A Total of 48,101 performance records of sows for Yorkshire and Landrace breeds were collected from swine breeding farms in Korea from 2001 to 2008. A general ingredient analysis included the fixed effects of breed, parity, year, season, and farm. For the number of heads per 1st parity analysis by each growth traits, the data of 48,101 heads was used to analyze growth traits group. In the general ingredient analysis, the results showed high significance except for lean percentage by season (p<0.05). Average daily gain of Landrace breed ($640.48{\pm}0.749g$) was better than that of Yorkshire breed ($624.22{\pm}0.608g$), and the backfat thickness of Yorkshire breed ($13.44{\pm}0.030mm$) was thicker than that of Landrace breed ($12.50{\pm}0.037mm$). For the number of born alive and number of stillborn by growth traits for each breed, number of born decreased after test end day of 161 to 165 day, and average daily gain of 620 g to 640 g and the highest number of born appeared at the backfat thickness of 13 mm to 14 mm for yorkshire breed. In case of Landrace breed, number of born was the highest, and the number of stillborn increased together with average daily gain. The number of born was high when backfat thickness was less than 11 mm. The number of born trended to decrease when backfat thickness increased.

• Journal of the Korean Society of Radiology
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• v.79 no.5
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• pp.254-258
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• 2018

Purpose: Establishment of an appropriate protocol for breast magnetic resonance imaging (MRI) in the study of image quality standards to enhance the effectiveness of medical image information exchange, which is part of the construction and activation of clinical information exchange for healthcare informatization. Materials and Methods: The recommended protocols of breast and MRI scans were reviewed and the questionnaire was prepared by a responsible researcher. Then, a panel of 9 breast dedicated radiologists was set up in Korea. The expert panel conducted a total of three Delphi agreements to draw up a consensus on the breast MRI protocol. Results: The agreed breast MRI recommendation protocol is a 1.5 Tesla or higher device that acquires images with prone position using a breast dedicated coil and includes T2-weighted and pre-contrast T1-weighted images. Contrast enhancement images are acquired at least two times, and include 60-120 seconds between images and after 4 minutes. The contrast enhancement T1-weighted image should be less than 3 mm in thickness, less than 120 seconds in temporal resolution, and less than $1.5mm^2$ in-plane pixel resolution. Conclusion: The Delphi agreement of the domestic breast imaging specialist group has established the recommendation protocol of the effective breast MRI.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.6
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• pp.697-703
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• 2023

As a part of the global industrial efforts to reduce environmental pollution owing to air pollution, regulations have been established by the International Maritime Organization (IMO). The IMO has implemented various regulations such as EEXI, EEDI, and CII to reduce air pollution emissions from ships. They are also promoting measures to decrease the power consumption in ships, aiming to conserve energy. Most of the power used in ships is consumed by electric motors. Among the motors installed on ships, the engine room blower that takes up a significant load, operates at a constant irrespective of demand. Therefore, energy savings can be expected through frequency control. In this study, we demonstrated the efficacy of energy savings by controlling the frequency of the electric motor of the generator blower that supplies combustion air to the generator's turbocharger. The system was modeled based on the output data of the turboharger outlet temperature in response to the blower frequency inpu. A PI control system was established to control the frequency with the target being the turbocharger outlet temperature. By maintaining the turbocharger design standard outlet temperature and controlling the blower frequency, we achieved an annual energy saving of 15,552kW in power consumption. The effectiveness of energy savings through frequency control of blower fans was verified during the summer (April to September) and winter (March to October) periods. Based on this, we achieved annual fuel cost savings of 6,091 thousand won and reduction of 8.5 tons of carbon dioxide, 2.4 kg of SOx, and 7.8 kg of NOx air pollutants on the training ship.

• Journal of Bio-Environment Control
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• v.32 no.4
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• pp.416-422
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• 2023

This study was aimed to determine the changes in CO₂ concentration according to the temperatures of daytime and nighttime in the CO₂ supplemental greenhouse, and to compare calculated supplementary CO₂ concentration during winter and spring cultivation seasons. CO₂ concentrations in experimental greenhouses were analyzed by selecting representative days with different average temperatures due to differences in integrated solar radiation at the growth stage of leaf area index (LAI) 2.0 during the winter season of 2022 and 2023 years. The CO₂ concentration was 459, 299, 275, and 239 µmol·mol^-1, respectively at 1, 2, 3, and 4 p.m. after the CO₂ supplementary time (10:00-13:00) under the higher temperature (HT, > 18℃ daytime temp. avg. 31.7, 26.8, 23.8, and 22.4℃, respectively), while it was 500, 368, 366, 364 µmol·mol^-1, respectively under the lower temperature (LT, < 18℃ daytime temp. avg. 22.0, 18.9, 15.0, and 13.7℃, respectively), indicating the CO₂ reduction was significantly higher in the HT than that of LT. During the nighttime, the concentration of CO₂ gradually increased from 6 p.m. (346 µmol·mol^-1) to 3 a.m. (454 µmol·mol^-1) in the HT with a rate of 11 µmol·mol^-1 per hour (240 tomatoes, leaf area 330m²), while the increase was very lesser under the LT. During the spring season, the CO₂ concentration measured just before the start of CO₂ fertilization (7:30 a.m.) in the CO₂ enrichment greenhouse was 3-4 times higher in the HT (>15℃ nighttime temperature avg.) than that of LT (< 15℃ nighttime temperature avg.), and the calculated amount of CO₂ fertilization on the day was also lower in HT. All the integrated results indicate that CO₂ concentrations during the nighttime varies depending on the temperature, and the increased CO₂ is a major source of CO₂ for photosynthesis after sunrise, and it is necessary to develop a model formula for CO₂ supplement considering the nighttime CO₂ concentration.

• Korean Journal of Agricultural Science
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• v.36 no.2
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• pp.135-145
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• 2009

This research was conducted to investigate the effect of various phosphorus concentrations in fertilizer solution on growth of and nutrient uptake by 'Chugyang' egg plant (Solanum melongena L.). Tissue and soil analyses were also conducted to set the threshold levels of phosphorus in plants when disorders develop for phosphorus deficiency or excess. Brown and purple areas developed on the margin of mature leaves and it enlarged rapidly in P deficient plants. The fruits in P deficient plants were small and dull purple in color. When P were excess in fertigation solution, the margins of lower leaves became scorched and it enlarged to inner part of the leaves. The fruits of P excess plants became small and had the curl shape. The tissue $PO_4$-P contents in the most recently fully expanded leaves and dry weight of full above ground plant tissue at 35 days after transplanting showed quadratic response ($y=0.7887+0.2394x-0.0197x^2$) and cubic response ($y=10.43+14.47x-4.7642x^2+0.3977x^3$) to elevated $PO_4$-P concentrations, respectively. When 10% reduction in dry weight set to threshold levels, optimum tissue $PO_4$-P contents are between 0.98 to 1.35%. The yield determined at 150 days after transplanting also showed cubic response to elevated phosphorus concentrations in fertigation solution ($y=1194.6+1502.2x-454.5x^2+35.64x^3$). When the 10% reduction in yield is set to threshold levels, the tissue $PO_4$-P contents for maximum yield should be around 1.53% to 2.25% in most recently fully expanded leaves at 150 days after transplanting.

• Research in Plant Disease
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• v.17 no.3
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• pp.342-350
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• 2011

Throughout the years 2008 to 2010, we analyzed approximately two thousand oriental melon samples collected from Seongju, using electron microscopy and testing by RT-PCR using primers specific for eight cucurbit-infecting viruses. Data from RT-PCR indicated that Cucumber green mottle mosaic virus (CGMMV), Watermelon mosaic virus 2 (WMV2) and Zucchini yellow mosaic virus (ZYMV) were present and the other viruses were not detected. Among them, CGMMV and WMV2 were the most prevalent pathogens. CGMMV was thought to infect oriental melon from the early growing season, and reached nearly 100% in the later of growing period. Otherwise, WMV2 emerged from June, several months later compared to CGMMV. CGMMV was detected from all aerial parts of the oriental melon including seeds, but not from the roots of the grafted pumpkin rootstock. Seed of two out of five commercial varieties were shown to be CGMMV positive. Nine varieties of pumpkins used as rootstocks were not infected with CGMMV. When the seedlings of grafted oriental melon were transplanted into pots mixed with the oriental melon debris infected with CGMMV, they were not infected by CGMMV. Cutting of pruning shear and the contact of tendrils contributed 48% and 30% to the transmission of the virus, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.255-261
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• 2020

This study was undertaken to evaluate the growth, body shape and carcass cutting yield traits of Duroc (D) and crossbred (Duroc×Pietrain×Pietrain; DPP) pigs. A total of 147 D and 101 DPP pigs were used for analyzing the growth trait, whereas 16 D and 16 DPP pigs were evaluated for carcass yields. Backfat thickness (BF) and average daily feed intake (ADFI) were significantly higher in D (14.07±0.24 mm, 2,101 g) than in DPP (12.69±3.25 mm, 1,909 g) (p <0.001). Moreover, D exhibited significantly higher body shape traits including body height (BH), chest depth (CD) and chest width (CW), as compared to DPP pigs (p <0.001). No differences were observed for body length (BL) between the two strains. Analysis of the carcass cutting yield traits determined for D and DPP were in the order: ham (HM; 31.17% and 33.43%), belly (BY; 23.40% and 19.55%), and picnic shoulder (PS; 16.54% and 16.87%), respectively. Then, HM showed a difference of 2.26% P with D(31.17%) and DPP(33.43%), while BY showed a difference of 3.85% P with D(23.40%) and DPP(19.55%). Taken together, our results indicate that DPP has a better feed efficiency than D, and therefore has the potential to increase the production of low-fat pork, targeting consumers having a high preference who have opted for a healthy lifestyle. These results can be used as basic data for developing an ideal pig breed.

• Journal of Ginseng Research
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• v.44 no.6
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• pp.815-822
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• 2020

Background: Recently, beneficial roles of ginsenoside F2 (GF2), a minor constituent of Panax ginseng, have been demonstrated in diverse inflammatory diseases. However, its roles in alcoholic liver inflammation and injury have not been clearly understood. Here, we investigated the underlying mechanism by which GF2 ameliorated alcoholic liver injury. Methods: To induce alcoholic liver injury, C57BL/6J wild type (WT) or interleukin (IL)-10 knockout (KO) mice were orally administered with ethanol (3 g/kg) or ethanol-containing GF2 (50 mg/kg) for 2 wk. Liver injury and infiltration of macrophages and neutrophils were evaluated by serum biochemistry and immunohistochemistry, respectively. The changes of hepatic immune cells were assessed by flow cytometry and polymerase chain reaction analysis. In vitro differentiation of naïve T cells was performed. Results: GF2 treatment significantly attenuated alcoholic liver injury, in which infiltrations of inflammatory macrophages and neutrophils were decreased. Moreover, the frequencies of Foxp3⁺ regulatory T cells (Tregs) increased but IL-17-producing T (Th17) cells decreased in GF2-treated mice compared to controls. Furthermore, the mRNA expression of IL-10 and Foxp3 was significantly increased, whereas IL-17 mRNA expression was suppressed in GF2-treated mice. However, these beneficial roles of GF2 were not observed in GF2-treated IL-10 KO mice, suggesting a critical role of IL-10. Similarly, GF2 treatment suppressed differentiation of naïve T cells into Th17 cells by inhibiting RORgt expression and stimulating Foxp3 expression. Conclusion: The present study suggests that GF2 treatment attenuates alcoholic liver injury by increasing IL-10 expression and Tregs and decreasing IL-17 expression and Th17 cells.