• Korean Journal of Veterinary Research
• /
• v.51 no.1
• /
• pp.1-6
• /
• 2011

Sixteen steers were used to investigate the efficacy of the sustained-release implant of bovine somatotropin (bST) in improving growth and feed:gain ratio during 12 weeks. Administration of the 400 mg bST implant resulted in a 16.1% increase in growth rate, and this increase was significant (p<.05). The use of the sustained-release implant did not alter (p>.05) feed intake and feed:gain ratio. Thirty-four cows were used to investigate the efficacy of the sustained-release implant of bST in milk production during 4 weeks. Administration of the 200 mg bST implant resulted in an 8.7% increase in milk production, and this increase was significant (p<.05). Twenty-four barrows were used to investigate the efficacy of the sustained-release implant of porcine somatotropin (pST) in improving growth, feed:gain ratio and backfat thickness during 6 weeks. Administration of the 120 mg pST implant resulted in a 11.4% increase in feed:gain ratio and a 60% decrease in backfat thickness, and these results were significant (p<.05). But the use of the sustained-release implant did not alter (p>.05) growth rate and feed intake.

• Proceedings of the Korea Technology Innovation Society Conference
• /
• 2006.05a
• /
• pp.3-17
• /
• 2006

Ideas do not become exhausted, and there are no diminishing returns in the creation of knowledge. Nonetheless, growth ultimately ceases in this simplest model of endogeneous innovation. But, if we treat knowledge capital as a public capital considering of its non-appropriable benefits, economic growth can be sustained in the economy. We showed that considering goodness of fit of regression model, we can see that the empirical evidence is strongly in favor of the character of knowledge as the public knowledge capital. So, we can expect that by product differentiation, economic growth can be sustained in the Korean economy.

• 한국생물공학회:학술대회논문집
• /
• 2000.04a
• /
• pp.541-545
• /
• 2000

For the sustained release formulation of recombinant human growth hormone (rhGH), dissociable rhGH aggregates were microencapsulated within poly(D,L-lactic-co-glycolic acid) [PLGA] microparticles. rhGH aggregates with 2 - 3 m Particle diameter were first produced by adding a small volume of aqueous rhGH solution into a partially water miscible organic solvent phase(ethyl acetate) containing PLGA. These rhGH aggregates were then microencapsulated within PLGA polymer phase by extracting ethyl acetate into an aqueous phase pre-saturated with ethyl acetate. The resultant microparticles were 2 - 3 m in diameter similar to the size of rhGH aggregates, suggesting that PLGA polymer was coated around the protein aggregates. Release profiles of rhGH from these microparticles were greatly affected by changing the volume of the incubation medium. The release rhGH species consisted of mostly monomeric form with having a correct conformation. This study reveals that sustained rhGH release could be achieved by microencapsulating reversibly dissociable protein aggregates within biodegradable polymers.

• Korean Journal of Veterinary Research
• /
• v.49 no.1
• /
• pp.9-15
• /
• 2009

The present study was carried out to examine the sustained release effect of the implantable bovine somatotropin (SRI-BST) formula. In the blood profile test in steers, the bovine somatotropin concentration in serum by radioimmunoassay showed the peak concentration on the first day after the implantation of the SRI-BST formula, and concentration proceeded for 5 days (p < 0.05). The insulin-like growth factor-1 concentration showed the peak concentration on the seventh day after implantation of the SRIF-BST formula, and concentration proceeded for 10 days (p < 0.05). The glucose showed the peak concentration on the first day after implantation of the SRI-BST formula, and concentration continued for 3 days (p < 0.05). The blood urea nitrogen showed the lowest concentration on the third day after implantation of the SRI-BST formula, and concentration continued for 7 days (p < 0.05). These results proved that the SRIF-BST formula was the sustained release effects in steers.

• International conference on construction engineering and project management
• /
• 2009.05a
• /
• pp.40-40
• /
• 2009

Construction firms have long sought success in the global construction market through diversifying revenue sources and project portfolios. The volume of international contracts has contributed to firms' sustained growth by mitigating the impact of the domestic market's cyclical nature. In spite of the importance of international construction, the uncertainty and dynamic changes surrounding global construction pose serious threats to global contactors. Over the last decade, the international construction industry has changed drastically in many ways, particularly including financial resource diversity, competition rules for the selection of contractors, and the terms of delivery systems requiring more competent total service providers. This paper investigates the important changes for global contractors through various documentation analysis as well as in-depth interviews with industry experts. This paper then analyzes the common strategies and lessons obtained from the cases of leading global contractors that have sustained their growth in the competitive global construction during the last decade. In addition, the authors further analyzed the comparisons between those firms and Korean contractors to discern any difference in sustaining their growth in the competitive market. It was found that those leading firms were quite proactive and responsive to changing markets by diversifying their market revenues to stabilize their revenue structure and enhancing their competency through a wide range of 'business convergence'. In addition, they significantly increased their upstream/downstream functional capabilities; hence becoming more competent service providers, able to grow in these rapidly changing market conditions. Finally, this paper benchmarks the critical strategies that support growth, which in turn can provide a strategic guideline for expansion into the global construction market.

• Proceedings of the PSK Conference
• /
• 2002.10a
• /
• pp.417.2-418
• /
• 2002

The rhGH-loaded PLGA microsphere formulation was prepared using a double emulsion process from hydrophilic 0:50 poly(D.L-lactide-co-glycolide) (PLGA) polymers. To investigate the sustained efficacy of this formulation, ts pharmacodynamic characteristics were analyzed. It showed particle size of ca 53.1 $\mu\textrm{m}$ with high drug ncorporation efficiency and it was sucutaneously administrated to hypophysectomized rats and whole body rowth responses of this formulation were compared to those of the different dosing patterns of rhGH. (omitted)

• ALGAE
• /
• v.30 no.1
• /
• pp.35-47
• /
• 2015

The marine sand-dwelling dinoflagellate Polykrikos lebourae possesses obvious gold-brown pigmented plastids as well as taeniocyst-nematocyst complex structures. Despite of the presence of the visible plastids, previous attempts to establish this species in culture all failed and thus the unavailability of cultures of this species has posed a major obstacle to further detailed exploration of ecophysiology of the dinoflagellate. Here, we isolated P. lebourae from sandy sediment of an intertidal flat on Korean western coast, successfully established it in culture, and have been maintaining the stock culture over the past 3 years. Using this stock culture, we explored phagotrophy and potential prey resources of P. lebourae, growth and grazing responses of P. lebourae to different prey organisms, the effect of prey concentration on growth and grazing rates and gross growth efficiency (GGE) of P. lebourae when fed three different prey organisms, and the growth kinetics of P. lebourae under different light regimes. P. lebourae captured prey cells using a tow filament and then phagocytized them through the posterior end. The dinoflagellate was capable of ingesting a broad range of prey species varying in size, but not all prey species tested in this study supported its sustained growth. GGE of P. lebourae was extremely high at low prey concentration and moderate or low at high prey concentrations, indicating that P. lebourae grows heterotrophically at high prey concentrations but its growth seems to be more dependent on a certain growth factor or photosynthesis of plastids derived from the prey. In the presence of prey in excess, P. lebourae grew well at moderate light intensity of $40{\mu}mol$ photons $m^{-2}s^{-1}$, but did not grow at dim and high (10 or $120{\mu}mol$ photons $m^{-2}s^{-1}$) light intensities. Our results suggest that the benthic dinoflagellate P. lebourae is an obligate mixotroph, requiring both prey and light for sustained growth and survival.

• Korean Journal of Veterinary Research
• /
• v.39 no.2
• /
• pp.267-275
• /
• 1999

Bovine somatotropin is known to improve the growth rate and lactation in cattle. In this study, we examined the concentration-time profiles of a sustained-release formulation of bovine somatotropin (BST) and insulin-like growth factor-1 (IGF-1) in plasma and milk in cows. In addition, the possible effect of co-administrated vitamin ADE complex on the pharmacokinetic parameters of BST and IGF-1 was evaluated. 1. Plasma BST and IGF-1 levels reached the peak at 12~24 and 48 hours after the administration of BST, and plasma half-lives ranged 100 to 137 and 201 to 310 hours, respectively. To 8th day after administration, BST and IGF-1 levels in milk were not significantly different from the control levels. 2. Plasma BST levels showed cyclic pattern with high concentrations in early stage after each injection and following gradual declining during repeated administrations at 2 week intervals, while plasma IGF-1 levels in treated animals did not show such a cyclic pattern, but remained higher than the control levels. 3. Milk BST and IGF-1 levels during repeated treatments were not significantly different from the control levels. 4. Co-administration of vitamin ADE complex yielded slightly increased AUC of plasma BST for high dose group, but such effect was not evident in the IGF-1 levels. Co-administration of ADE complex tended to increase plasma BST levels and decrease the elimination half-life of IGF-1. 5. These results suggest that the BST formulation tested is one of the ideal sustained-release formulation for long term use in dairy industry. As for the co-administration of vitamin ADE complex, the benefit of co-administration with BST is needed to be further evaluated.

• Journal of Korea Technology Innovation Society
• /
• v.10 no.1
• /
• pp.47-72
• /
• 2007

Ideas do not become exhausted, and there are no diminishing returns in the creation of knowledge. Nonetheless, growth ultimately ceases in this simplest model of endogeneous innovation. The reasons are similar to those that are discussed in the context of the neoclassical model of capital accumulation. Even if the resource cost of creating new goods does not rise, the economic return to invention may decline as the number of available products increases. When the rate of return to R&D falls to the level of the discount rate, private agents cease to be willing to defer consumption in order to invest in product development. But, if we treat knowledge capital as a public capital considering of its non-appropriable benefits, economic growth can be sustained in the economy. Romer(1986) has pointed out that growth might be sustainable if the accumulation of knowledge is not subject to long-run diminishing returns. Actually Romer assumed diminishing returns in the production of private knowledge from available resources, but increasing returns in the production of output from labor and total (public and private) knowledge. His condition for the sustainability of long-run growth amounts to an assumption that the diminishing returns in the former activity do not outweigh the increasing returns in the latter. The Johansen(1988) cointegration test method is used for finding long-run equilibrium relationship between R&D input and the product innovation. Test results indicate the existence of cointegrating equation between each pair of regression variables including dependent variable in the knowledge production function. And, the signs of cointegrating vectors are well accord to the prediction of sustainable growth. In the empirical analysis, from all cases of the form for the knowledge production function, we could not reject the null hypothesis that R&D spillover effect is significant($H_{0}:\;{\gamma}=1$). In summary, we showed that considering goodness of fit of regression model, we can see that the empirical evidence is strongly in favor of the character of knowledge as the public knowledge capital. So, we can expect that by product innovation, economic growth can be sustained in the Korean economy.

• Asian Journal of Business Environment
• /
• v.14 no.2
• /
• pp.19-30
• /
• 2024

Purpose: This research article investigates the intricate relationship between economic growth and employment in the Korean agri-food industry. Research design, data and methodology: Drawing on Okun's law, which proposes a negative correlation between economic growth and unemployment, the study explores the applicability of this law to different sectors. By focusing on the agri-food industry, the study examines the impact of economic growth on both full-time and temporary employment. Results: The findings highlight the industry's role as a buffer, absorbing workers from other sectors, particularly manufacturing. Moreover, the study reveals that temporary employment is more sensitive to economic growth fluctuations compared to full-time employment. Conclusions: The research emphasizes the importance of implementing employment programs that support transitioning workers in the agri-food industry, facilitating knowledge and skill transfer to ensure sustained employment. Furthermore, it recommends government and company support for temporary employment during buffering periods to ensure safe job transitions. This study provides valuable evidence to understand the nuanced relationship between economic growth and employment in the Korean agri-food industry.