• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.3
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• pp.298-310
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• 2021

Freshwater eel Anguilla japonica is a commercially important species in East Asia. However, given the continuously decreasing resources due to many problems as climate change, habitat destruction and overfishing, mass seed production is crucial. In particular, the eel larvae present a unique life history, spending prolonged periods in the Pacific Ocean. Therefore, finding suitable feed that lasts through the long larval stages is rather difficult. In the present study, we histologically observed the development of digestive organs for 50 days after hatching (DAH). The endogenous reserves were completely absorbed at 7 DAH, and the first exogenous feeding started thereafter. The teeth appeared at 4 DAH and dramatically changed from needle-like to broad-based types by 50 DAH. The intestine remained as straight gut until 50 DAH. The intestinal cilia appeared first at 6 DAH and their density continuously increased thereafter. Interestingly, goblet cells appeared in the intestine, but not in the esophagus, where these cells are commonly observed in other teleosts. In addition, high amounts of eosinophil substances, assumed to be zymogen granules, accumulated in the pancreas, suggesting a specific digestive strategy of this species. Overall, these observations largely update the previous reports and can be useful to improve A. japonica seed production.

• The Journal of Fisheries Business Administration
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• v.52 no.4
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• pp.45-63
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• 2021

The purpose of this study is to analyze the structure, status and economic ripple effects of the fisheries processing industry in Korea using interindustry analysis. Five input-output tables published over the past twenty years have been reclassified with a focus on the fisheries processing sector. Through these multi-period tables, we analyzed changes in the inducing effects in production, value added and employment as well as the backward-forward linkage effects. As a result of the analysis, it was found that the industrial scale of the fisheries processing industry is very small compared to other food manufacturing industries. The backward linkage effect of the fisheries processing industry was greater than that of other industries, but the forward linkage effect was rather low. This means that the fisheries processing industry can be greatly affected by industrial depression of the downstream industries such as fishery and aquaculture. Production and employment-inducing effects of the fisheries processing industry have shown a decreasing trend in recent years. This reflects the reality that intermediate inputs are gradually being replaced by imports from domestic production due to the expansion of market opening and the depletion of fishery resource. In the future, it is necessary to prepare a strategy to increase the value-added productivity of the fisheries processing sector and foster it as an export industry.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.285-285
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• 2022

Recent unpredictable climate change is a major cause of rice yield loss. In particular, methane is a key factor in global warming. Therefore rice breeders are trying to breed the reducing-methane gas emission rice using the crossbreeding method. However, the traditional crossbreeding method takes 8 to 10 years to breed a cultivar, and the anther culture method developed to shorten the breeding cycle also takes 6 to 7 years. On the other hand, CRISPR/Cas9 accurately edits the target trait and can rapidly breed rice cultivars by editing the target trait as a homozygous in 2-3 years. In addition, exogenous genetic elements such as Cas9 can be isolated from the G₁ generation. Therefore, the flowering time was regulated by applying CRISPR/Cas9 technology, and OsCKq1 genome-editing (OsCKq1-G) rice with early flowered and high yield was bred in the field. Genome-editing of OsCKq1 applied CRISPR/Cas9 technology up-regulates the expression of the flowering promotion gene Ehd1 under long-day conditions induces early flowering and increases the yield by increasing the 1,000-grain weight. And as the generations advanced, each agricultural trait indicated a low coefficient of variation. As a result, indicated that OsCKq1 plays an important role in regulating the flowering time and is related to the trait determining yield. Therefore, OsCKq1-G can suggest a breeding strategy for the Net-Zero national policy for reducing-methane gas emission rice by shortening the breeding cycle with the early flowered, and high-yield rice. CRISPR/Cas9 technology is a rapid and accurate breeding technology for breeding rice cultivars with important characteristics.

• Korean Journal of Poultry Science
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• v.42 no.3
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• pp.247-256
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• 2015

There are approximately 1,500 broiler farms in Korea, each raising 55,000 birds. Ninety-five percent of the farms are contracted with Integration Company. According to the Korean broiler performance index, broilers in Korea are marketed at 32 days with 1.52 kg of body weight. In contrast, the market age and body weight of broilers are 47 days/2.8 kg in the United States and 42 days/2.5 kg in Europe. Because of the younger market age of the Korean broiler, the pre-starter feed is important. Chicks exhibit poor absorption of dietary nutrients up to 7 days after hatching due to an immature digestive system and low enzyme secretion rate and activity. At the beginning of hatching, chicks obtain their nutrients from the egg yolk sac. It is highly recommended that chicks, after consuming the nutrients in the egg yolk sac, are given supplemented pre-starter feed to increase early growth rates and improve the performance of broiler production. Pre-starter nutrient requirements are not expressed in NRC, so Korean feeding standards for poultry and commercial breeding companies determine the nutrient requirements of pre-starter broiler chickens. Three approaches are followed to formulate specially designed pre-starter feeds for broiler chicks: (i) selective use of raw materials, (ii) proper standards of nutrient supply, and (iii) application of feed additives such as exogenous enzymes. In the selection of raw materials, those with high digestibility can be used. The absorption rate of carbohydrates in grains can be increased through feed processing at high temperature and high pressure. Soy proteins and fish meal can also be added as protein sources. As an energy source, vegetable oils are preferred over animal fats because of the former's high digestibility. It is suggested that the levels of proteins and amino acids are higher in pre-starter feed than in starter feed. With regard to energy, the sources of energy are more important than the levels of energy in feed. Feed additives such as exogenous enzymes can be used to improve nutrient digestibility. In addition, organic acids and plant extracts can be used as alternatives to animal growth promoters to stimulate immunity and prevent diseases. The growth performance of broilers is affected by various factors, such as management and disease control, in addition to the nutritional strategy; however, nutritional strategies play an important role in improving the productivity of broilers. Therefore, nutritional strategies, along with management and disease control, are required for improving the productivity of broilers in Korea.

• Journal of Bio-Environment Control
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• v.23 no.4
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• pp.329-336
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• 2014

As an abiotic stress, chilling stress is one of the major factors limiting plant growth and increasing susceptibility to pathogens. Therefore, enhancing stress tolerance in plants is an important strategy for their survival under unfavorable environmental conditions. The objective of this study was to determine the effects of the exogenous application of salicylic acid (SA) or nitric oxide (NO) on chilling tolerance in pepper seedlings. Pepper (Capsicum annuum L. 'kidaemanbal') seedlings were grown under normal growing conditions ($20/25^{\circ}C$, 15 hours photoperiod, $145{\pm}5{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, fluorescence lamps) for 23 days after transplanting. The solution (3 mL) of 1 mM SA and 0.3 mM NO with surfactant triton 0.1% were sprayed two times a week, respectively. Right after the completion of chemical application, seedlings were subjected to chilling condition at $4^{\circ}C$ for 6 hours under dark condition and then the seedlings were recovered at the normal growing conditions for 2 days. In order to assess plant tolerance against chilling stress, growth characteristics, chlorophyll fluorescence (Fv/Fm), and membrane permeability were determined after chilling stress imposition. Total phenolic concentration and antioxidant capacity were measured during the whole experimental period. Disease incidence for pepper bacterial spot and wilt was also analyzed. Pepper seedlings treated with SA or NO were maintained similar dry mass ratio, while the value in control increased caused by chilling stress suggesting relatively more water loss in control plants. Electrolyte leakage of pepper seedlings treated with SA or NO was lower than that of control 2 days after chilling treatment. Fv/Fm rapidly decreased after chilling stress in control while the value of SA or NO was maintained about 0.8. SA increased higher total phenolic concentration and antioxidant capacity than NO and control during chemical treatment. In addition, increase in total phenolic concentration was observed after chilling stress in control and NO treatment. SA had an effect on the reduction of bacterial wilt in pepper seedlings. The results from this study revealed that pre-treatment with SA or NO using foliar spray was effective in chilling tolerance and the reduction of disease incidence in pepper seedlings.

• KDI Journal of Economic Policy
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• v.14 no.3
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• pp.3-21
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• 1992

By localizing the production of core parts and intermediate goods previously imported from Japan, Korean firms have been striving to increase their market share and profit in the final goods market in which Japanese firms are dominating. Korean producers' efforts, however, have often been thwarted by Japanese suppliers' "strategic" behavior. This competitive strategy involves Japanese exporters supplying parts and intermediate goods at very high prices until Korean firms must locally develop them, and then setting the prices far below the previous level so that the profitability of localization is dramatically reduced, or even means a loss for the Korean manufacturer. This paper intends to explain the strategic behavior of Japanese firms through the concepts of strategic interactions and joint economies. Strategic interactions can be aggressive or accommodating depending on whether competitors are dealing with strategic substitutes or complements. Joint economies exist in multi-stage competition when competition in the previous state favorably influences "profits" of the ensuing stage. Competiton between Korean and Japanese firms (a two-stage game involving production and technology rivalries) can be characterized by joint economies and strategic substitutes: joint economies since technological improvement results in more profits in the production stage; and strategic substitutes since an increase in marginal profits of one firm brings about a decrease in marginal profits of the other in a duopolitic production stage. This implies that the flood of "low price" Japense substitutes is an almost "natural" phenomenon in the context of the duopolistic market described in this paper. In the technology competition stage, on the other hand, technology development and technology transfer can be either strategic complements or substitutes. This implies that, in typical comparative static analyses, the effect of changes in exogenous variables cannot be expected a priori. Thus it becomes very difficult to determine the desirability of applying various policy measures such as countervailing duties, R&D subsidies, and creating demand for localized products. For these reasons, it is indeed likely that the measures suggested as means of circumventing the strategic behavior of Japanese firms (and enhancing technological development of Korean firms) may not work.

• Korean Journal of Health Education and Promotion
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• v.23 no.3
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• pp.99-119
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• 2006

Objectives: This study intends to understand the difference within group of social support level and the effect of social support to health behaviors and health status of the elderly by selecting the old of local society as target. Methods: Data were obtained from self-administered questionnaire of 8,688 persons, older than 65 years, living in a community. We measured the sociodemographic characteristics, social support(family support, other support, quality of support), physical health state(subjective health status, number of chronic disease), physical function state(activities of daily living; ADL, instrumental activities of daily living; IADL), cognition state(mini-mental state examination-Korean; MMSE-K) and depression state(short form of geriatric depression scale; SGDS), health behaviors(smoking, drinking, exercise, eating habit). Univariate, multinominal logistic regression and covariance structure analysis were employed to analyze factors affecting on the social support of the elderly. Results: When considering the degree of social support by the sociodemographic characteristics of the older adults, the family support, other support and quality of support is better when the old is male, young, high education and self-reported living status is good and it has significance statistically. When considering the relation between social support and health status, the family support, other support and quality of support is better when the old's subjective and objective physical health status is good. The family support, other support and quality of support is better when the old's subjective health status is better. The other support and quality of support is better when the old's ADL(activities of daily living) and IADL(instrumental activities of daily living) are good. The family support, other support and quality of support is better when the old's cognitive function and depression state is better. When considering the relation between social support and health behaviors, in case of smoking and drinking, the quality of support, family support and other support is better when the old smokes and drinks rather than the old does not. In case of exercise and eating habit, the family support, other support and quality of support is better when the old exercises and eats regularly rather than the old does not. It has significance statistically. From the result of performing covariance structure analysis by structural equation modeling(SEM) with two endogenous variable(health behaviors and health status) and one exogenous variable(social support), factor loading of health status is 0.74 and factor loading of health behaviors is 0.05. The social support explains health status of 55.4% and health behaviors of 2.9%. Conclusions: This study has the meaning that it finds the difference of social support generating from inside of the group for the old residing in city and country and specifies the effect that the difference of social support influences to health status and health behaviors. From now on, in the development of health improvement strategy of the olds, it is necessary to approach from inclusive aspect while considering psychosocial factor such as social support and social economical factor as well as health status.

• Journal of Microbiology and Biotechnology
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• v.25 no.9
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• pp.1467-1475
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• 2015

The use of microbial extracts containing plant hormones is a promising technique to improve crop growth. Little is known about the effect of bacterial cell-free extracts on plant growth promotion. This study, based on phytohormonal analyses, aimed at exploring the potential mechanisms by which Enterococcus faecium LKE12 enhances plant growth in oriental melon. A bacterial strain, LKE12, was isolated from soil, and further identified as E. faecium by 16S rDNA sequencing and phylogenetic analysis. The plant growth-promoting ability of an LKE12 bacterial culture was tested in a gibberellin (GA)-deficient rice dwarf mutant (waito-C) and a normal GA biosynthesis rice cultivar (Hwayongbyeo). E. faecium LKE12 significantly improved the length and biomass of rice shoots in both normal and dwarf cultivars through the secretion of an array of gibberellins (GA₁, GA₃, GA₇, GA₈, GA₉, GA₁₂, GA₁₉, GA₂₀, GA₂₄, and GA₅₃), as well as indole-3-acetic acid (IAA). To the best of our knowledge, this is the first study indicating that E. faecium can produce GAs. Increases in shoot and root lengths, plant fresh weight, and chlorophyll content promoted by E. faecium LKE12 and its cell-free extract inoculated in oriental melon plants revealed a favorable interaction of E. faecium LKE12 with plants. Higher plant growth rates and nutrient contents of magnesium, calcium, sodium, iron, manganese, silicon, zinc, and nitrogen were found in cell-free extract-treated plants than in control plants. The results of the current study suggest that E. faecium LKE12 promotes plant growth by producing GAs and IAA; interestingly, the exogenous application of its cell-free culture extract can be a potential strategy to accelerate plant growth.

• Journal of muscle and joint health
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• v.8 no.1
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• pp.5-26
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• 2001

Many studies have reported that regular aquatic exercise can lead to improvement of health for patients suffering from arthritis. In spite of these benefits, the adherence rate has shown as few as 26% of patients with arthritis who had completed the aquatic exercise education program. Moreover, when patients with arthritis begin an aquatic exercise, 47% withdraw within the first 6 month. No study has been found that constructs model to explain aquatic exercise adherence of patients with arthritis. The purpose of this study were to identify the factors influencing exercise adherence and to construct and test a structural model to explain aquatic exercise adherence of patients with arthritis. Hypothesized model was constructed on the basis of Bandura's social cognitive theory and literature review. Exogenous latent variables included in this model are group cohesion and barrier, endogenous latent variables are self-efficacy, outcome expectancy and self-evaluation. Empirical data used was collected through individual interviews with the structural questionnaire on 249 patients with arthritis who had completed the 6-week aquatic exercise education program of Korean Rheumatology Health Professionals Academy. The interviews were performed from September 6, 1999 through October 8, 1999. A model tested by the covariance structural analysis with LISREL 8.12a program and by descriptive statistics and correlation with SAS 6.12 program. The results are summarized as follows: First, hypothesized model showed a good fit to the empirical data. In the modified model added one new path showed a much better fit. Second, group cohesion had a direct, indirect positive effects, self-efficacy and self evaluation had a direct positive effects on exercise adherence. Barrier had a direct, indirect negative effects on exercise adherence. Outcome expectancy had a direct negative effect, indirect positive effects through self-evaluation on exercise adherence, but total effects was not significant. Total effect size of the variables were group cohesion, self-efficacy, barrier and self evaluation in order. All variables accounted for 54% of the total variance of exercise adherence in the model. In conclusion, this model confirmed to be proper in explaining of aquatic exercise adherence. Group cohesion, self-efficacy, outcome expectancy, self-evaluation, barrier contributed to the aquatic exercise adherence of patients with arthritis. The results of this study suggested that improvement of group cohesion, self-efficacy and self-evaluation, motivation of outcome expectancy through self-evaluation, and reduction of the barrier should be included in the strategy of nursing intervention for the aquatic exercise adherence of patients with arthritis.

• Journal of Distribution Research
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• v.16 no.1
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• pp.1-27
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• 2011

I. Introduction: This study is to examine the structural relationships among exogenous variable (preliminary and post-support, franchisee's perceived business possibility, communication, moral hazard), the mediated variables(satisfaction, perceived risk, trust) and dependent variable(recontracting intention) in the food service franchise industry context. More specifically, this study has considered some realistic characteristics factors influencing satisfaction, perceived risk and trust between franchisors and franchisees and their further recontracting intention from the perspective of a practical approach. In this study, 437 data has been collected and used for the SPSS and AMOS analysis. The data were analyzed with structural equation modeling. Since the result of the overall model analysis demonstrated a good fit, we could further analyze our data. II. Research Model: This study is to examine the structural relationships among preliminary and post-support by franchisor, franchisee's perceived business possibility, and communication, moral hazard, has on effect on franchisee's satisfaction, perceived risk, trust and recontracting intention in the food service franchise industry context. Hypotheses are as following (Stern & EL-Ansary 1988; Oliver, 1997;Kee & Knox, 1970; Moorman, Deshpande & Zaltman, 1993; Perron, 1998; Zaheer, McEvily, Perrone, 1998). III. Result and Implication: We examined franchisee who have food service stores for samples of this study. The data were analyzed with structural equation modeling using path analysis. The result of the overall model analysis appeared as following: ${\chi}^2$ = 61.578 (d.f.=9, p<0.01), CFI =.990, GFI =.973, AGFI =.863, RMR =.019, RMSEA= .116, NFI = .988, TLI = .959. The findings can be summarized as follows: First, preliminary and post support of franchisor, perceived business possibility and communication positively influence to franchisee's satisfaction. Second, moral hazard of franchisor has negatively influence to franchisee's satisfaction and positively influence to perceived risk. Third, franchisee's satisfaction and trust has positively influence to recontracting intention. Fourth, franchisee's perceived risk has negatively influence to trust and recontracting intention. We can concluded that franchisor's preliminary and post support of franchisor, perceived business possibility and communication may be considered as the important factors influence to franchisee's satisfaction. Moral hazard has become a focused issue in franchise industry. Finally, the managerial implication has been stated as followings: First, in the process of building a systematic industry support franchise system and developing a creative business model, franchisee's stable profitability should be considered as the first important factor. The franchisee's trust to franchise may become a dominant factor that influence the business expansion of franchisor. Second, franchisor should communication with their franchisees and deal with the realistic difficulties faced by them with an effort. Third, the franchisor should achieve a synergy effect by utilizing the win-win strategy. The moral hazard strategy that achieving the profit through franchisee's damage will not be inadvisable to franchisor. Then the long-term oriented development and profitability can be maintained. To do so, the franchise industry may break away from the traditional business structure to improve management transparency and competitiveness on investment and organizational changing management. The conflict between franchisor and franchisee also can be reduced and big success can be achieved in the franchise industry.