• Journal of Sericultural and Entomological Science
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• v.14 no.2
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• pp.81-92
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• 1972

Studies on Pathogenicity of Nosema bombycis Naegeli are summarized as follows: 1. The mortality of the parents, Jam 103 and Jam 104, is remarkbly higher than that of the hybrid, Jam 103$\times$Jam 104, whereas there is no difference in the mortality between the parents. 3. In the mortality of the pathogen-concentration, it is increased in order of the following concentrations inoculated, 10$^{8}$ , 10$^{7}$ , 10$^{8}$ and 10$^{5}$ /ml. 3. In the mortality of each instar, it is high in order of 5th, 4th, 3rd, and 2nd instar. 4. In the interaction between the mortalities of the varieties and the concentrations, 1) The mortality shows no differences between the parents and the hybrid in the high concentration of 10$^{8}$ /ml. 2) The mortality of the hybrid is lower than that of the parents in the low concentration of 10$^{5}$ /ml, whereas no difference is found between the parents. 3) The interaction appears at the same level in the middle concentration of 10$^{6}$ /ml to the parents and of 10$^{7}$ /ml to the hybrid. 5. It was pointed out that active immunity depends upon the volume of antigen injection, immunizing period, and injection intervals. In this experiment, it is noticed that the optimum volume of injection is above 20ml and D is the best one of the four treatment (A.B.C.D.). 6. The immune sera indicate such a 12,800 high titer in the indirect method can be obtained from the D immunizing method. Silkworm tissues and N. bombycis spores show self-fluorescence, but it is able to distinguish it from the F.I.T.C. by using the U.V. filter. 7. The midgut epithelium is examined to be the first site of the tissues which are penetrated into and multiplied by the inoculation of the pathogen per os.

• Journal of The Korean Society of Grassland and Forage Science
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• v.36 no.2
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• pp.150-158
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• 2016

This study was conducted to evaluate growth characteristics, yield and feed value of newly developed domestic teosinte (Geukdong 6) compared to widely cultivated silage corn hybrid (31N27) and sorghum ${\times}$ sudangrass hybrid (P877F). Geukdong 6, a new single cross (Teosinte ${\times}$ Suwon 19) variety, is a teosinte (Zea may L. ssp. maxicana) developed by the Geukdong 6 of agricultural company corporation (GACC) in An-dong province. This field experiment was designed in a randomized block design with three replications and consisted of silage corn (T1), sorghum x sudangrass hybrid (T2) and Geukdong 6 (T3). Leaf length, number of leaves, number of tillers and fresh yield of T3 were higher than that of T1 and T2 (p<0.05). Dry matter yield of T3 was lower than that of T1 (p<0.05). In particular, T3 ($0.1kg/cm^2$) showed to be very tender compared to other T1 ($0.5kg/cm^2$) and T2 ($0.5kg/cm^2$), (p<0.05). The crude protein content of T3 as 8.25% was higher than that of T2 (5.90%), (p<0.05). However, there was no significant differences between T1 (8.14%). The brix degree of T2 was higher than that of T1 and T3 (p<0.05). T3 showed higher content of total minerals compared to T1 and T2 (p<0.05). The relative palatability of T3 was higher than T1 and T2 (p<0.05), when fed to deer as soiling crop. However, it showed a lower than T1 in Korean native cattle and korean native goats. The relative palatability of the silage shown in order of T1> T3> T2 in korean native cattle, spotted deer, and korean native goats. As mentioned above the results, Geukdong 6 (T3) could be recommended as using of soiling and lab silage, when high fresh yield, tender stem, number of many leaf, content of high crude protein, and palatability higher than sorghum ${\times}$ sudangrass hybrid were considered.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.1
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• pp.21-25
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• 2014

Singwangok, a new single cross variety, was developed by the maize breeding team at the National Institute of Crop Science (NICS), RDA in 2012. This hybrid, consisting of a high yield of grain, was produced by crossing two inbred lines, KS172 and KS173. KS172 is the seed parent and KS173 is the pollen parent of Singwangok. It is a yellow-orange intermediate maize hybrid (Zea mays L.). After the preliminary yield trial and advanced yield trial of Singwangok (Suwon185) in Suwon for 2 years, the regional yield trial of that was subsequently carried out for its growth characteristics and yield at 3 different locations from 2010 to 2012. It was named as Singwangok. The silking date of Singwangok is similar to the check hybrid, Jangdaok. The plant height of Singwangok is similar to Jangdaok, but its ear height ratio is lower than that of Jangdaok. Moreover, it has a resistance to lodging. The ear number per 100 plants of Singwangok is more 17 than that of Jangdaok, whereas the ear length of Singwangok is similar to Jangdaok. Further, the weight of 100 seeds of Singwangok is similar to Jangdaok. It has a moderate resistance to southern leaf blight (Bipolaris maydis) and a strong resistance to northern leaf blight (Exserohilum turcicum). Furthermore, it has a moderate resistance to the black streaked dwarf virus (BSDV), ear lot and corn borer. The grain yield of Singwangok, 7.81 ton/ha, was similar to that of Jangdaok. The seed production of Singwangok was well processed due to the good match during crossing between the seed parent, KS172 and the pollen parent, KS173, in Yeongwol; the F1 seed yield was 3.84ton/ha. Singwangok would be a suitable cultivar to all plain areas in Korea.

• Horticultural Science & Technology
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• v.33 no.1
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• pp.47-54
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• 2015

This research was conducted to investigate the changes in moisture retention capacities of expanded rice-hull (ERH)-based root media and their influences on the growth of mother and daughter plants in vegetative propagation of 'Seolhyang' strawberry. The proportion of water at the container capacity of ERH medium was in the range of 20 to 23%. This range was lower than the 60 to 66% of strawberry-specialized medium, the 30 to 34% of soil mother material (SMM) and the 30 to 35% of loamy sand. The moisture content of ERH was reduced to 10 to 12% at 8 hours after irrigation, and there were large variations among replications of ERH medium. Among four kinds of root media formulated to contain ERH, the medium of ERH + coir dust (CD) (55 + 45%, v/v) had 26.5 and 32.5% water contents at 20 and 40 days after irrigation to daughter plants, respectively. The m edia o f ERH + sandy loam (S L) and E RH + S MM showed similar trends i n moisture r etention. The pH and EC i n the all root media tested were in the range of 6.7 to 7.1 and 0.03 to $0.08dS{\cdot}m^{-1}$, respectively. The pHs and ECs measured at 20 and 40 days after irrigation were not significantly different in each root medium. Among the root media formulated to contain ERH, the growth of daughter plants was the highest in the treatment of ERH + SL (55 + 45%, v/v). As the blending rate of coir dust was elevated in the ERH + CD media, moisture retention capacity increased gradually, but the growth of daughter plants became worse even though the medium showed higher moisture retention capacity than other root media tested. The growth of roots and aboveground tissues of daughter plants deteriorated in the root media formulated by blending ERH + perlite (PE) at various ratios. The results of this research suggest the optimum formulations of root media and management of moisture content in raising of strawberry daughter plants when ERH is a component of root media.

• Horticultural Science & Technology
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• v.34 no.1
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• pp.195-205
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• 2016

Sugar beet cyst nematode, Heterodera schachtii, causes serious economic losses worldwide in Brassicaceae crops. In 2011, this nematode was first found in highland vegetable cultivation areas in Korea, and thereafter spread to the surrounding healthy Chinese cabbage fields. However, little has been documented on the biological and ecological characteristics of the sugar beet nematode in highland vegetable cultivation areas. In this study the dispersal of the sugar beet cyst nematode was examined, focusing on spreading through soil and/or water infested with the nematode. When farmers with work boots trampled on Chinese cabbage fields for 10 minutes, the number of cysts recovered from the soil attached to the working differed depending on the research sites. Under irrigation conditions of 2, 4, and 8 liters of water per $m^2$, the amounts of soils attached on the bottom of the work boots and the number of healthy cysts in the soils increased significantly with the increase in soil moisture, although the total number of cysts, eggs, and juveniles did not increase significantly. After driving on the farm road adjacent to cabbage fields infested with the sugar beet cyst nematode, cysts were also recovered from the soil attached to the vehicle's tires, suggesting that the sugar beet cyst nematode can spread to new fields through soil carried by vehicles and by farmers. An excavator and a motor truck could deliver 41 kg and 224 g, respectively, of soil on the shovel shoes and the wheels to other locations during the Chinese cabbage harvest, suggesting that farming equipment and transportation vehicles may be vital means by which the cyst nematode spreads to non-infested fields in the highland area of Korea. Runoff water also contained cysts, whose amounts increased after water irrigation onto the ridges to simulate rainy conditions, with no significant difference in the number of cysts with increasing amounts of irrigation water. All of these results confirmed that the sugar beet cyst nematode spreads through soil attached to work boots, harvesting tools, and transportation vehicles, especially during the harvest time, and through runoff water on rainy days. These observations suggest that personal sanitization and cleaning of working tools and vehicles are one of the most important means to prevent the dispersal of the sugar beet cyst nematode in fields.

• Journal of agriculture & life science
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• v.43 no.1
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• pp.51-59
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• 2009

The chemical components and antimicrobial activities of garlic from different area were investigated and analyzed to provide basic data for functional food materialization and processing. Hunter's values of garlic from different area were L 53.41~57.15, a -3.49~-4.38 and b 11.47~17.55. The moisture, crude protein, crude fat, nitrogen free extract, crude fiber and ash were 65.24~71.96, 6.24~9.35, 0.21~0.49, 19.01~22.72, 0.58~0.95 and 1.01~2.01%, respectively. The major minerals of garlic from different area were Na(27.22~112.03), Mg(18.17~32.56), K(242.16~569.28), Ca(28.60~63.93), P(117.72~265.21 mg%) and major free sugars were sucrose, glucose and fructose. The major amino acids of garlic from different area were proline, arglmne, glutamic acid and aspartic acid and content of total amino acid was 2,709.33~4,561.04 mg%. The ascorbic acid content of garlic from different area was 2.966~8.673 mg%. Composition of fatty acids of garlic from different area were linoleic acid, oleic acid and palmitic acid, unsaturated fatty acid and saturated fatty acid contents were 72.18~74.35 and 25.65~27.82%, respectively. Antimicrobial activities of garlic extracts as different area increased depends on concentration and showed the high antimicrobial activities against Gram(+) and Gram(-).

• Journal of agriculture & life science
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• v.50 no.1
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• pp.105-115
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• 2016

This study was carried out to establish the optimum forest management plan for the Cryptomeria japonica plantations in southern inland and Jeju island in Korea. Sixty seven circular sample plots of 0.04ha were established and we surveyed vegetation structure and growth characteristics from three layers(upper, middle, and lower). As a result of cluster analysis obtained by importance values of each tree species, the community type of C. japonica stands were classified into C. japonica group(C1) and C. japonica-C obtusa group. C. obtusa community were also sbudivided into P. thunbergii-Q. serrata group(C2) and Q. serrata-C obtusa group(C3). In tree layers importance value(IV) of C. japonica were 97.2% in C1, 80.7% in C2, and 47.6% in C3 and in sub-tree layers IV were 8.9% in C1, 15.2% in C2, and 5.7% in C3. Especially in C3 there are bamboo species (Smilacina japonica var. lutecarpa and Pseudosasa japonica) it is necessary for us to control them. In shrub layers C. japonica were found in C1(9.2%) and C2(7.0%), but except for C3. In tree layer species diversity indices of each community ranged from the lowest 0.059 in C1 to the highest 0.548 in C3. Dominance ranged from 0.958 in C1 to 0.393 in C3 which may caused by interspecific competition. Current annual increment of diameter growth ranged from 7.01mm/yr to 8.04mm/yr. As a result of our study we recommend the application of proper thinning and pruning for C1 and C2.

• Journal of Wetlands Research
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• v.25 no.4
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• pp.353-365
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• 2023

The effects of climate change on green infrastructure and environmental media remain uncertain and context-specific despite numerous climate projections globally. In this study, the extreme weather conditions in seven major cities in South Korea were characterized through statistical analysis of 20-year daily meteorological data extracted fro m the Korea Meteorological Administration (KMA). Additionally, the impacts of extreme weather on Nature-based Solutions (NbS) were determined through a comprehensive review. The results of the statistical analysis and comprehensive review revealed the studied cities are potentially vulnerable to varying extreme weather conditions, depending on geographic location, surface imperviousness, and local weather patterns. Temperature extremes were seen as potential threats to the resilience of NbS in Seoul, as both the highest maximum and lowest minimum temperatures were observed in the mentioned city. Moreover, extreme values for precipitation and maximum wind speed were observed in cities from the southern part of South Korea, particularly Busan, Ulsan, and Jeju. It was also found that extremely low temperatures induce the most impact on the resilience of NbS and environmental media. Extremely cold conditions were identified to reduce the pollutant removal efficiency of biochar, sand, gravel, and woodchip, as well as the nutrient uptake capabilities of constructed wetlands (CWs). In response to the negative impacts of extreme weather on the effectiveness of NbS, several adaptation strategies, such as the addition of shading and insulation systems, were also identified in this study. The results of this study are seen as beneficial to improving the resilience of NbS in South Korea and other locations with similar climate characteristics.

• Journal of Nutrition and Health
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• v.57 no.1
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• pp.53-64
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• 2024

Purpose: Mitochondria play a crucial role in preserving skeletal muscle mass, and damage to mitochondria leads to muscle mass loss. This study investigated the effects of oxypeucedanin hydrate, a furanocoumarin isolated from Angelica dahurica radix, on myogenesis and mitochondrial function in vitro and in zebrafish models. Methods: C2C12 myotubes cultured in media containing 0.1, 1, 10, or 100 ng/mL oxypeucedanin hydrate were immunostained with myosin heavy chain (MHC), and then multinucleated MHC-positive cells were counted. The expressions of markers related to muscle differentiation, muscle protein degradation, and mitochondrial function were determined by quantitative reverse transcription polymerase chain reaction. To investigate the effects of oxypeucedanin hydrate on mitochondrial dysfunction, Tg(Xla.Eef1a1:mito-EGFP) zebrafish embryos were treated with 5-fluorouracil, leucovorin, and irinotecan (FOLFIRI) with or without oxypeucedanin hydrate and analyzed for mito-EGFP intensity and mitochondrial length. Results: Oxypeucedanin hydrate significantly increased MHC-positive multinucleated myotubes (≥ 3 nuclei) and increased the expression of the myogenic marker myosin heavy chain 4. However, it decreased the expressions of muscle-specific RING finger protein 1 and muscle atrophy f-box (markers of muscle protein degradation). Furthermore, oxypeucedanin hydrate enhanced the expressions of markers of mitochondrial biogenesis (peroxisome proliferator-activated receptor-gamma coactivator 1 alpha, transcription factor a mitochondrial, succinate dehydrogenase complex flavoprotein subunit A, and cytochrome c oxidase subunit 1) and mitochondrial fusion (optic atrophy 1). However, it reduced the expression of dynamin-related protein 1 (a mitochondrial fission regulator). Consistently, oxypeucedanin hydrate reduced FOLFIRI-induced mitochondrial dysfunction in the skeletal muscles of zebrafish embryos. Conclusion: The study indicates that oxypeucedanin hydrate promotes myogenesis by improving mitochondrial function, and thus, suggests oxypeucedanin hydrate has potential use as a nutritional supplement that improves muscle mass and function.

• Journal of The Korean Association For Science Education
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• v.29 no.8
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• pp.990-1010
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• 2009

To derive brain-based evolutionary educational principles, this study examined the studies on the structural and functional characteristics of human brain, the biological evolution occurring between- and within-organism, and the evolutionary attributes embedded in science itself and individual scientist's scientific activities. On the basis of the core characteristics of human brain and the framework of universal Darwinism or universal selectionism consisted of generation-test-retention (g-t-r) processes, a Model of Brain-based Evolutionary Scientific Teaching for Learning (BEST-L) was developed. The model consists of three components, three steps, and assessment part. The three components are the affective (A), behavioral (B), and cognitive (C) components. Each component consists of three steps of Diversifying $\rightarrow$ Emulating (Executing, Estimating, Evaluating) $\rightarrow$ Furthering (ABC-DEF). The model is 'brain-based' in the aspect of consecutive incorporation of the affective component which is based on limbic system of human brain associated with emotions, the behavioral component which is associated with the occipital lobes performing visual processing, temporal lobes performing functions of language generation and understanding, and parietal lobes, which receive and process sensory information and execute motor activities of the body, and the cognitive component which is based on the prefrontal lobes involved in thinking, planning, judging, and problem solving. On the other hand, the model is 'evolutionary' in the aspect of proceeding according to the processes of the diversifying step to generate variants in each component, the emulating step to test and select useful or valuable things among the variants, and the furthering step to extend or apply the selected things. For three components of ABC, to reflect the importance of emotional factors as a starting point in scientific activity as well as the dominant role of limbic system relative to cortex of brain, the model emphasizes the DARWIN (Driving Affective Realm for Whole Intellectual Network) approach.