• Korean Journal of Microbiology
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• v.50 no.4
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• pp.308-312
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• 2014

In this study, we conducted a next generation sequencing based microbial community analysis to investigate gut microbiota of the two commercially most available swine breeds, Yorkshire and Landrace. Bacterial 16S rRNA gene was amplified from fecal DNA using universal primer sets designed for V4 regions. Our comparison analysis of the gut microbiota of the two breeds suggested that their gut microbiota changed depending on the growth stages, while the difference between the two breeds was insignificant. However, there was a limited number of genera, the abundance of which was found to be different between the breeds. Those included the genus Xylanibacter in the Yorkshire samples, which was previously reported as a fiber digesting bacteria, likely increasing energy harvesting capacity of swine. In addition, others included opportunistic pathogens mostly found in the Yorkshire samples while the Landrace samples had significantly more prevalent Clostridium_IV species that were known to play a key role in systemic immunity of hosts. While microbial community shifts was found to be associated with growth stages, the difference between the two breeds seemed to be insignificant. However, there were several bacterial genera showing differential abundance, which may affect growth of hosts.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.4
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• pp.438-443
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• 1999

Germination and growth of Laminaria japonica microscopic stages were investigated under crossed gradients of temperatures and irradiances, and the results related to the seasonal temperature regime in the southeastern coast of Korea. Germination rates of $70\~86\%$ were observed in the temperature range of $5\~20^{\circ}C$, however, at $25^{\circ}C$ no germination of meiospores was observed. The primary factor affecting germination rates at the temperature range of $5\~20^{\circ}C$ was irradiance: germination was significantly reduced at $150 {\mu}E{\cdot}m^{-2}{\cdot}s^{-1}$. Vegetative cell production of female gametophytes was highest at $20^{\circ}C$, but plants were not fertile at the temperature. In the temperature range of $5\~15^{\circ}C$, higher irradiance caused females to reduce cell production, but increased fertility. Cell production was also low at lower temperatures with increased fertility rates. Optimal growth temperature for microsporophytes was $10^{\circ}C$ and their growth rates were light-saturated at $70 {\mu}E{\cdot}m^{-2}{\cdot}s^{-1}$. We have concluded that meiospores released before July could develope to the young sporophytic stage in the southeastern coast of Korea which is off the southern limit of its geographical distribution. However, limiting factor in the development of natural sporophytic population in this region would be the upper temperature limit for the survival of young sporophytes, as water temperature at this area frequently exceeds $25^{\circ}C$ during the summer period.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.2
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• pp.31-46
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• 2019

As the importance of venture firms has increased as a new growth engine, the South Korea government makes various efforts to establish healthy ecosystems for ventures and start-ups. Especially in order to foster the competitiveness of venture firms, various support policies such as financial and R&D expenses are being expanded and promoted. In this study, the author analyzed the impact of government funding on venture firms' internal competencies and management performance by using the resource-based theory. Moreover, this study tested the moderation effect of firm's growth stages. Unlike previous studies, this study focused on qualitative rather than quantitative aspects of internal competencies and the financial and non-financial performance are used to measure the management performance of the ventures to examine the effects of government funding for venture firms in more details. For the purpose of verifying the hypothesis of this research, "The Research On The Precision Status Of Venture Firms" in 2017 from the Ministry of Small and Medium Business was utilized, which has been compiled since 1999. According to the results of this study, the government funding experience did not significantly affect the company's internal competencies and financial performance, but had a significant impact on the non-financial performance, which in turn seemed to have a significant effect on the financial performance. In addition, it was found that the technology, price, design, and quality competencies affected non-financial performance, while the organizational management and marketing competencies did not. However, the price, design, organizational management, and marketing competencies affected financial performance, while the technology competency was not. Finally, there were no differences in the effectiveness of government funding, depending on the growth stages.

• Asian Journal of Turfgrass Science
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• v.7 no.2_3
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• pp.81-94
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• 1993

This study was conducted to investigate the influence of herbicides, simazine, pendimethalin, propyzamide and asulam on the growth of Zoysia matrella when they are treated at different growth stages of the plant. The reaction of Zoysia matrella to herbicides differed depending on kinds of herbicides, their concentcations, and time of treatment. Simazine at the higher concentration of 600g /l0a exhibited inhibitory effect on leaf dry matter and growth of runner when treated on April 5, 1991. The highest inhibition of leaf and runner was observed in the plot applied on May 23, 1990. The sprouting and growth of Zoysia matrella was not affected by all the concentrations of the herbicides applied on October 23,1991. Pendimethalin did not influence the growth of Zoysia matrella at he treatment of April 5. However, at the treatment of May 23, the number and growth of runner was inhibited although the plant height and leaf dry matter was not affected. When pendimethalin was treated on October 23, the growth of runner was very slightly reduced in the next year. In case of propyzamide, there was no inhibitory effect on the growth of Zoysia matrella regardless of treatment of times, methods, and dosages. Greater inhibition in the growth of Zoysia matrella was observed at higher dosage(1,ll0g /l0a)-treated plot on April 5 and all the concentrations treated on May 23. But, no inhibition was observed on the October 23 treatment.

• Fisheries and Aquatic Sciences
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• v.26 no.7
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• pp.447-454
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• 2023

Fast somatic growth is important considerations for successful and competitive aquaculture industry. In rainbow trout reared in South Korea, triploid induction was used to suppress negative influence of reproductive maturation to body growth. However, the effects of triploidy are visible in both mature fish and developing juvenile fish. Thus, it is also important to explicate the effect of triploid induction on growth during the early-life stages of rainbow trout-alevins and fry. Rainbow trout fertilized eggs were subjected to triploid induction and polyploidy was checked by flow cytometry. Diploid and triploid alevins and fry were reared separately in tanks with constant flow of freshwater through flow-through water system and growth measurements were done from zero days after hatching (DAH 0) until DAH 134. The egg-yolk morphometrics of alevins-yolk length, yolk height, yolk volume and yolk weight-were statistically similar (p > 0.05) in both genotypes from DAH 0 to DAH 22. The total length, body height, and body weight of alevins and fry were statistically better (p > 0.05) in both genotypes until DAH 92 but thereafter, triploid had a significantly better growth performance (p < 0.05) over diploid fish until the completion of study at DAH 134. With that, triploid induction did not influence alevin yolk regions and body growth and fry somatic growth until around 3 months after hatching, but considerable growth enhancement was subsequently apparent.

• Horticultural Science & Technology
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• v.29 no.1
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• pp.36-42
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• 2011

This research was conducted to investigate the effects of irrigation quantity in irrigation management system controlled by drainage level sensors for perlite bag culture on the growth and yields of tomatoes during different growth stages. Tomato plants were irrigated with four selected methods; supplying small quantity (~70 mL) during entire growth (S-S), large quantity (~145 mL) during entire growth (L-L), small quantity before harvesting the first cluster fruits and large quantity after harvesting (S-L), and large quantity until harvesting the first cluster fruits and small quantity after harvesting (L-S). The irrigation quantity supplied in each time was gradually adjusted along with the ratios as the tomato crop grew during different growth stages. The growth of the tomato plants was unstable and slow during the entire cropping period when the plant was irrigated by small or large quantities (S-S or L-L). In L-S treatment, the growth phase of the tomato was changed from vegetative to generative growth on the basis of the plant development index when each irrigation quantity was changed. The L-S treatment exhibited the largest root volume and yields with stable drainage ratios. Therefore, the optimum irrigation quantity was determined as 145 mL before harvesting the first cluster fruits and 70 mL after harvesting.

• Journal of Bio-Environment Control
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• v.28 no.1
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• pp.38-45
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• 2019

Recycling of drained nutrient solution in hydroponic cultivation of horticultural crops is important in the conservation of the water resources, reduction of production costs and prevention of environmental contamination. Objective of this research was to obtain the fundamental data for the development of a recirculation system of hydroponic solution in semi-forcing cultivation of 'Bonus' tomato. To achieve the objective, tomato plants were cultivated for 110 days and the contents of inorganic elements in plant, supplied and drained nutrient solution were analyzed when crop growth were in the flowering stage of 2nd to 8th fruiting nodes. The T-N content of the plants based on above-ground tissue were 4.1% at the flowering stage of 2nd fruiting nodes (just after transplanting), and gradually get lowered to 3.9% at the flowering stage of 8th fruiting nodes. The tissue P contents were also high in very early stage of growth and development and were maintained to similar contents in the flowering stage of 3rd to 7th fruiting nodes, but were lowed in 8th node stages. The tissue Ca, Mg and Na contents in early growth stages were lower than late growth stages and the contents showed tendencies to rise as plants grew. The concentration differences of supplied nutrient solution and drained solution in $NO_3-N$, P, K, Ca, and Mg were not significant until 5 weeks after transplanting, but the concentration of those elements in drained solution rose gradually and maintained higher than those in supplied solution. The concentrations of B, Fe, and Na in drained solution were slightly higher in the early stages of growth and development and were significantly higher in the mid to late stages of growth than those in supplied solution. The above results would be used as a fundamental data for the correction in the inorganic element concentrations of drained solution for semi-forcing hydroponic cultivation of tomato.

• Korean journal of food and cookery science
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• v.32 no.5
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• pp.656-663
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• 2016

Purpose: This study was aimed to compare the nutritional content of the life stages of Tenebrio molitor. Methods: Nutritional element analysis comprised 12 minerals, 18 amino acids, 4 vitamins, and 12 fatty acids in larval, pupal, and adult stages. Nutritional element content was expressed as a percentage of 100 g of sample and determined in raw and freeze-dried samples to assess the food value of the insect. Results: Moisture, crude protein, and crude fat contents in raw samples were 63.5%, 23.19%, and 3.96%, respectively. Moisture content was significantly higher in the adult stage than in larval and pupal stages, whereas crude fat and crude ash contents were lower. Mineral composition of the mealworm showed K, P, and Mg in decreasing order of content, with no differences among life stages. Total amino acid content increased from adult, pupal to larval stages, in order with each stage's growth, without difference in amino acid composition. Seventy-six to 78% of total fatty acid corresponded to unsaturated fatty acids, with oleic acid as the most abundant. In addition, fatty acid content was high in the adult stage, and clear differences were observed between life stages. Finally, vitamins B1 and B3 showed similar content between life stages, whereas vitamin B2 showed a higher content the adult than larval and pupal stages. A higher folate content was observed in pupal and adult stages than in the larval stage. Although freeze-dried samples showed a higher nutritional content than raw samples, both samples were similar in composition and content between life stages, suggesting the suitability of freeze-dried samples for use as food materials. Conclusion: These results may provide a basis for more diversified industrial applications of the Tenebrio molitor.

• Proceedings of the Korean Society of Crop Science Conference
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• 1988.07a
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• pp.12-13
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• 1988

• Proceedings of the Korean Vacuum Society Conference
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• 2001.02a
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• pp.74-74
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• 2001