• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.1
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• pp.11-20
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• 2004

This pot experiment was conducted to investigate the effects of combined micronutrient application($T_1$;control, $T_2$; Fe, $T_3$; Fe＋Mn, $T_4$: Fe＋Mn＋Cu, $T_5$ ; Fe＋Mn＋Cu＋Zn, $T_6$ ; Fe＋Mn＋Cu＋Zn＋Mo, $T_7$ ;Fe＋Mn＋Cu＋Zn＋Mo＋B) on forage performance of pure and mixed cultures of orchardgrass and white clover. This 4th part was related to the changes in the contents of micronutrients(Fe, Mn, Cu, Zn, Mo, and B) in forages. The results obtained are summarized as follows: 1. General differences have been showed in the contents of micronutrients based on the treatments, forage species, pure/mixed culture, cutting order, and additional fertilization, especially N. Compared to pure culture, orchardgrass showed relatively high contents of Mn and Zn, and low contents of B and Fe in mixed culture. White clover, however, tended to be exactly opposed to the above trends. The contents of Cu and Mo did not show any differences between pure and mixed cultures. 2. In relative comparison, the $T_7$ influenced negatively on the contents of Cu, Zn, and Mo in orchardgrass. The $T_7$ also influenced negatively on the contents of Mo in white clover. However, the $T_7$ influenced positively on the contents of Mn in orchardgrass, and also influenced positively on the contents of Fe, Mn, and Cu in white clover. Because of the antagonism between Fe and Mn, the Fe contents in both forages were significantly decreased by the $T_3$. Under the various conditions, the differences among Fe contents tended to be more significant in white clover than in orchardgrass. 3. At the $T_6$ and $T_7$, the Mo contents in both forages tended to be relatively high. The Mo contents, however, were somewhat decreased by the $T_7$ 7/. The Mo-toxicity, which was caused by the high Mo-contents, tended to be diminished, and was likely to be prevented by the optimum B/Mo ratio and B application($T_7$ ).

• Korean Journal of Poultry Science
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• v.17 no.3
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• pp.157-166
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• 1990

Data are presented concerning the effect of different seasons and sexes during the growing period on broiler performance. Total 38, 451 broiler chickens were raised in spring summer and winter and they were marketed at 6 or 7 weeks of age. Birds were alloted to 118 groups (240∼360 birds per pen) and weighted at termination in order to determine variation in several economic traits between the sex groups. The results obtained were summarized as follows ： 1. The rate of livability of the females were higher than that of the males in all seasons (P＜0.01). 2. Body weights of males were heavier than that of females by 17.4％ at 6 wks, and 19.1％ at 7 wks of age and by 18.0∼19.6％ ,17.6∼18.4％ , and 19.6∼19.3％ in spring, summer, and winter, respectively (P＜0.01). 3. Males consumed more feed than females by 13.3∼135％ . And same trends was noted by season ： 11.7∼13,5％ in spring 175∼15.0％ in summer, and 11.5∼13.0％ in winter. 4. Peed requirement of the females was less than that of the males ： by 5.0∼7.1％, 5.9∼1.0％ , and 5.4∼5.5％ in spring, summer, and winter, respectively (P＜ 0,01). 5. The correlation coefficients between body weight and feed intake in spring were 0.81∼0.87 in males, and 0.84∼0.88 in females and those between body weight and feed requirements were ∼052∼0.51 in males, and -0.17∼-0.45.45 in females. 6. In summer the correlation coefficients between livability and body weight were -0.1∼-0.37 in males, and -0.36∼-0.51 in females, those between body weight and feed intake were 0.66∼0.77 in males, and 0.5∼0.82 in females, and those between body weight and feed requirement were -0.42∼-022 in males, and 0.24∼-0.001 in females. 7. In winter the correlation coefficients between livability and body weight were -0.02∼0.02 in males, -0.18∼-0.19 in females, those between body weight and feed requirements were -0.08∼02 in males, and 0.04∼0.09 in females.

• Journal of Life Science
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• v.23 no.11
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• pp.1325-1335
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• 2013

Working dogs, such as rescue dogs, military watch dogs, guide dogs, and search dogs, are selected by in-training examination of desired traits, including concentration, possessiveness, and boldness. In recent years, genetic information has been considered to be an important factor for the outstanding abilities of working dogs. To characterize the molecular features of the canine genes related to phenotypes for working dogs, we investigated the 24 previously reported genes (AR, BDNF, DAT, DBH, DGCR2, DRD4, MAOA, MAOB, SLC6A4, TH, TPH2, IFT88, KCNA3, TBR2, TRKB, ACE, GNB1, MSTN, PLCL1, SLC25A22, WFIKKN2, APOE, GRIN2B, and PIK3CG) that were categorized to personality, olfactory sense, and athletic/learning ability. We analyzed the chromosomal location, gene-gene interactions, Gene Ontology, and expression patterns of these genes using bioinformatic tools. In addition, variable numbers of tandem repeat (VNTR) or microsatellite (MS) polymorphism in the AR, MAOA, MAOB, TH, DAT, DBH, and DRD4 genes were reviewed. Taken together, we suggest that the genetic background of the canine genes associated with various working dog behaviors and skill performance attributes could be used for proper selection of superior working dogs.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.3
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• pp.169-178
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• 2003

This pot experiment was conducted to find out the effects of boron application($B_{0}$ ; control, $B_1$; 0.2, $B_2$; 2.0, B$_3$; 6.0, $B_4$; 15.0 boron me/pot) on the forage performance of pure and mixed cultures of orchardgrass and white clover. The third part was concerned with the changes in the contents and yields of nitrogen compounds(crude/pure protein and soluble N-compound) in forages. The results obtained are summarized as follows: 1. With no additional fertilization, especially nitrogen, in a pure culture, the $B_{0}$ and $B_4$ treatments on white clover decreased the amount of crude/pure protein, and showed nitrogen deficiency symptoms. However, the optimum boron application($B_2$) positively resulted in the increase of crude and pure protein, especially pure protein, and the content ratio of pure protein/soluble N-compounds. With additional fertilization, especially nitrogen, differences were not found among the boron treatments($B_{0}$, $B_2$, and $B_4$). 2. Owing to the decline of white clover as affected by the additional fertilization, especially nitrogen, in the grass-clover mixed cultures, the effects of B-application on these contents of white clover were different and relatively low, compared with the pure cultures. But the positive effect of $B_2$ treatment tended to be similar to the pure cultures. Also, it was recognized that the $B_2$ treatment resulted in the increase of their contents in orchardgrass, however, the effect was relatively minor compared with that of white clover. 3. The optimum B application(B$_2$) on white clover influenced relatively better on the yields of crude and pure protein than on the dry matter yields, especially with no additional fertilization. The effects of boron application on the contents and yields of crude and pure protein were different according to the forage species, whether it was a pure or mixed culture, and additional fertilization.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.4
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• pp.237-246
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• 2003

This pot experiment was conducted in order to find out the effects of application of combined micronutrients(T$_1$: control. T$_2$; Fe, T$_3$; Fe+Mn, T$_4$； Fe＋Mn＋Cu, T$_{5}$; Fe+Mn+Cu＋Zn, T$_{6}$；Fe+Mn+Cu＋Zn+Mo, T$_{7}$； Fe+Mn+Cu+Zn+Mo+B) on forage performance of pure and mixed cultures of orchardgrass and white clover The 2nd part was concerned with the changes in the forage yields and concurrence index. The results obtained are summarized as follows: 1. The effects of combined micronutrient applications on the forage yields were different according to the forage species, whether it was a pure or mixed cultures, and additional fertilization(especially N). The effects of them on the forage productivity and botanical composition were more obvious in white clover, especially in mixed culture, than in orchardgrass. By the significant role of B as a regulator, the yields of both forages were best in the T$_{7}$, respectively. 2. In the pure culture, the high yields of both forages were obtained by the T$_{7}$ and T$_2$, whereas the T$_{6}$ and T$_3$resulted in the low yields. The best yields of both forages were obtained by the T$_{7}$ with relatively optimum ratios among the micronutrients as follows; Fe/Mn/Cu/Zn, Fe/Mo, Mo/B, and ∑ cation/∑anion. It was observed the multiple interaction of Fe${\times}$Mn${\times}$Mo${\times}$B, and the significant role of B as a regulator. The effects of them on white clover were more distinct at no additional fertilization than at the additional fertilization(especially N). 3. In mixed culture, the optimum applications of them resulted in the positive increase of yield and botanical composition of white clover, whereas orchardgrass tended to be inversely except the T$_{7}$.X> 7/. 7/.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.3
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• pp.159-168
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• 2003

This pot experiment was conducted in order to find out the effects of boron application($B_{0}$ /; control, $B_1$; 0.2, $B_2$; 2.0,$ B_3$; 6.0, $B_4$; 15.0 B me/pot) on the forage performance of pure and mixed cultures of orchardgrass and white clover. The 2nd part was concerned with the changes in the forage yields and concurrence index. The results obtained are summarized as follows: 1. The optimum boron application($B_2$) generally resulted in the increase of both forage yields, but the effects of boron application on them were different according to the forage species, whether it was a pure or mixed cultures, additional fertilization, and cutting order. The effects of boron application on the forage productivity were more obvious in white clover than in orchardgrass. 2. Owing to the decline of white clover as affected by the application of additional fertilizers, especially N, in the grass-clover mixed cultures, the effects of boron application on the white clover yields showed a numerical inferiority compared with the pure culture. It was recognized that the yield increase and botanical composition of white clover in grass-clover mixed cultures could be regulated by the application of additional fertilizers and boron. 3. The toxic boron application($B_3$ and $B_4$) resulted in a decreased yield of both forages. The yield change of orchardgrass tended to be similar between pure and mixed cultures, whereas it of white clover tended to be more negative in mixed than in pure cultures. 4. With the application of additional fertilizers, especially N, the botanical composition and concurrence index in grass-clover mixed cultures were relatively increased in orchardgrass, and decreased in white clover. The botanical composition of orchardgrass increased from 55% to 75%, whereas it of white clover decreased from 45% in the first half cutting to 25% in the second half cutting, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.3
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• pp.179-186
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• 2003

This pot experiment was conducted to find out the effects of boron application( $B_{0}$ ) ; control, B$_1$; 0.2, $B_2$; 2.0, $B_3$; 6.0, $B_4$; 15.0 boron me/pot) on the forage performance of pure and mixed cultures of orchardgrass and white clover. The fourth part was concerned with the changes in the contents of B, Fe, Mn, Cu, and Zn in forages. The results obtained are summarized as follows: 1. The boron(B) contents of both forages and their differences among the B treatments generally decreased according to the cutting order. The B contents of white clover were somewhat lower in the $B_{0}$ than in the $B_2$. However, the differences in the yields between $B_{0}$ and $B_2$ were relatively great. It was probably caused by the latent B-deficiency in the $B_{0}$. Compared with white clover, the B contents of orchardgrass had relatively great differences between the $B_{0}$ and B$_2$, but both yields tended to be similar. 2. The contents of Fe, Mn, Cu, and Zn in both forages were generally different according to the forage species, whether it was a pure or mixed cultures, and additional fertilization. The effects of B application on their contents were different according to the micronutrients and above factors. 3. The Fe contents of white clover were lower in the $B_{0}$ and $B_4$ than in the$ B_2$. It tended to be related to the weak growth of roots and low yields in the $B_{0}$ and $B_2$. However, there were not consistent in the changes of contents of Mn, Cu, and Zn by the rates of B application. 4. The effects of B application on the total ion concentrations of Fe, Mn, Cu, and Zn were not consistent in both forages. However, the concentrations were generally affected by the changes in the contents of Mn and Zn. The concentrations of white clover were higher in a pure than in mixed culture.

• Korean Journal of Environment and Ecology
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• v.36 no.2
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• pp.177-201
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• 2022

Following the adoption of the global plant conservation strategies at the Conference of the Parties for Biodiversity Conservation, diligent actions to achieve each targets are actively carried out. In particular, the need for ecological conservation research to achieve targets 2 and 7 of GSPC-2020 has increased. The priority taxa to accomplish the objectives of GSPC-2020 are rare and endemic plants. In particular, endemic plants with limited distribution in specific regions are evaluated to face a high risk of extinction. To address the necessity to preserve endemic plants, we investigated the distribution of Prunus choreiana H. T. Im, a Korean endemic plant. After that, we examined the vegetational environment of the habitat of P. choreiana and evaluated its population structure. The productivity of its fruits and the effects of pollinators on fruit production were evaluated as well. The fruiting ratio was calculated based on the number of flowers produced. Lastly, we observed the annual growth characteristics of P. choreiana. The habitats of P. choreiana did not show a specific type of vegetation. All of them were located in a limestone area of Gangwon-do in the central Korean Peninsula and occupied a site where the coverage of the tree layer and the sub-tree layer was not high or did not exist. The population structure of P. choreiana contained a high proportion of mature plants capable of producing fruits and a low proportion of seedlings and Juvenile plants. We found that the production of fruits required pollinators and was affected by the performance of each plant. Although P. choreiana produces many flowers, only a maximum of 20% and only 2-6% on average bear fruits. These flowering characteristics may be due to pollinators' low abundance and activity during the flowering season (between mid-March and early April), suggesting that many flowers are needed to attract more pollinators. We rarely observed the re-establishment of seedlings in the population of P. choreiana. Despite that, we predict the population to persist owing to its long lifespan and periodic production of numerous fruits. However, if the tree layer and sub-tree layer in competing status with P. choreiana increase their crown density, they are expected to inhibit the growth of P. choreiana and affect the risk of its extinction. Therefore, the current changes in the vegetational environment of the habitats are expected to decrease the number and extent of P. choreiana in the long term. The results of this study may serve as primary and important data necessary for the achievement of GSPC-2020 objectives.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.1
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• pp.9-16
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• 2022

Rice is one of the most important staple foods in Wnju, Jeonbuk, South Korea. However, rice consumption has dramatically decreased as eating habits have diversified owing to rapid economic growth. Recently, floury endosperm rice varieties have been developed to invigorate the rice processing industry, because dry-milled rice flour is economically and environmentally suitable for massive rice flour distribution. The National Institute of Crop Science has developed 'AromaT', an early-maturing black rice with floury-endosperm, suitable for tea and dry milling. 'AromaT' was derived from a cross between 'Suweon542' as the floury endosperm source and 'Heugjinju' as the black and aromatic source. In this study, 'AromaT' and its parents, 'Suweon542' and 'Heugjinju', were analyzed for agronomic traits, anthocyanin content, and their major physicochemical properties by different planting date. The field experiment was conducted in Wanju, Jeollabuk-do Province, South Korea, in 2019. The transplanting dates were May 30 (ordinary season), June 25 (double-cropping season), and July 10 (late season). The yield performance of brown rice 'AromaT' was 330 kg/10 a in the double-cropping cultivation method and was the highest among the transplanting dates. The floury endosperm of 'AromaT' was derived from 'Suweon542' containing 'flo7', located on chromosome 5 and known to control floury endosperm. With the late planting date, the anthocyanin content of 'AromaT' was 570.5 mg/100 g, much higher than that of 'Heugjinju' (376.3 mg/100 mg). The brown rice of 'AromaT' also exhibited the pop-corn-flavoring 2-acetyl-1-pyrroline, exclusively detected in aroma rice varieties. The average particle sizes of 'AromaT' and 'Suweon542' were 67.12 ㎛ and 70.9 ㎛, respectively, lower than that of 'Heugjinju' (95.5 ㎛) with a black transparent endosperm. The average damaged starch content of 'AromaT' was 8.1%, lower than that of 'Heugjinju' (10.05%) and Suweon542 (9.5%). As a result, 'AromaT' with high anthocyanin content, fine particle size, and low damaged starch content is expected to provide a new rice material in various processing fields.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.18 no.6
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• pp.57-70
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• 2023

The investigation delved into 457 pieces of scholarly work, encompassing articles, published theses, and dissertations from the National Research Foundation of Korea, spanning the period of the 1997 IMF financial crisis up to 2022. The materials were sourced using terms such as 'angel investment', 'angel investor', and 'angel investment attraction'. The initial phase involved filtering out redundant entries from the preliminary collection of 267 works, leaving aside pieces that didn't pertain directly to angel investment as indicated in their abstracts. The next stage of the analysis involved a more rigorous selection process. Out of 43 papers earmarked in the preceding cut, only 32 were chosen. The criteria for this focused on the exclusion of conference presentations, articles that were either not submitted or inconclusive, and those that duplicated content under different titles. The final selection of 32 papers underwent a thorough systematic literature review. These documents, all pertinent to angel investment in South Korea, were scrutinized under five distinct categories: 1) publication year, 2) themes of research, 3) strategies employed in the studies, 4) participants involved in the research, and 5) methods of research utilized. This meticulous process illuminated the existing landscape of angel investment studies within Korea. Moreover, this study pinpointed gaps in the current body of research, offering guidance on future scholarly directions and proposing social scientific theories to further enrich the field of angel investment studies and analysis also seeks to pinpoint which areas require additional exploration to energize the field of angel investment moving forward. Through a comprehensive review of literature, this research intends to validate the establishment of future research trajectories and pinpoint areas that are currently and relatively underexplored in Korea's angel investment research stream. This study revealed that current research on domestic angel investment is concentrated on several areas: 1) the traits of angel investors, 2) the motivations behind angel investing, 3) startup ventures, 4) relevant institutions and policies, and 5) the various forms of angel investments. It was determined that there is a need to broaden the scope of research to aid in enhancing and stimulating the scale of domestic angel investing. This includes research into performance analysis of angel investments and detailed case studies in the field. Furthermore, the study emphasizes the importance of diversifying research efforts. Instead of solely focusing on specific factors like investment types, startups, accelerators, venture capital, and regulatory frameworks, there is a call for research that explores a variety of associated variables. These include aspects related to crowdfunding and return on investment in the context of angel investing, ensuring a more holistic approach to research in this domain. Specifically, there's a clear need for more detailed studies focusing on the relationships with variables that serve as dependent variables influencing the outcomes of angel investments. Moreover, it's essential to invigorate both qualitative and quantitative research that delves into the theoretical framework from multiple perspectives. This involves analyzing the structure of variables that have an impact on angel investments and the decisions surrounding these investments, thereby enriching the theoretical foundation of this field. Finally, we presented the direction of development for future research by confirming that the effect on the completeness of the business plan is high or low depending on the satisfaction of the entrepreneurs in addition to the components.