• Child Health Nursing Research
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• v.4 no.1
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• pp.60-75
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• 1998

The parents have much expectation upon the pregnancy and child birth, and in most cases, they expect the healthy parturient child. However, we can be placed on the high-risk conditions which have the physical, social and immature infant, due to the unexpected results, among the new-born. Accordingly, these high-risk newborn and premature infants will be mostly in NICU, which the concentrated medical treatment can be given, upon their conditions. After their birth and during these periods, they will be divided from the parents, and the nurse will accomplish the bringing-up activities which they can take care of the infant, expected by the parents after their birth. The hospitalization of high-risk newborn including these premature infants is the shocking experience to the parents of family, and thus they can feel the fear and uneasiness, and these reactions of parents are troubled in the behavior at the usual days, and cause the disorder and spiritless status, and these results break the supporting ability of parents, and cause the obstruction. Also, the unavoidable division between the parents and the children as like hospitalization of children can make the parents to feel the alienation emotionally, and this causes the results which the pride on the bringing-up ability of baby gets to be lost. These problems can cause the difficulties on the bonding or the parenting in the further days, and can be related to the neglect and abuse of children. Also, it is gradually increased to study and report which the emotional division by the physical division between the mother and the baby obstructs the normal affection course between the parent and the infant. The stress caused by the birth and the hospitalization of high-risk newborn, as like this, is important in the points which it can uncertainly affect the potential energy for the relationship of parent-child who are finally healthy. Accordingly, the significance and purpose of this study are to understand the contents and degree of stress which the parents of high-risk newborn including the immature child can be experienced from the hospitalization of ICU for their new borns, and thus to offer the basic program to the nursing intervention program for these. The subject of this study is the mother of newborn in NICU of 10 General Hospitals located at the 3one of Pusan, Korea from September 1997 to October 1997, and thus makes the subject of 95 person of parents who agreed to take part in the study and it is descriptive study related to the stress of mother having the newborn in NICU. The method is based on the preceding study related to the stress of mother having the experience of child hospitalization and chronic disease child, and then acquires the advice of specialists group as like 5 nursing professors, and then is amended and supplemented. Total number of questions is 43 items and consists of 5 factors as like medical treatment &nursing procedures, disease status & prognosis, role of parents, communication & inter-personal relationships, hospital environment, and is 5 point Likert Scale. The reliability of this study method is very highly shown to be Cronbach α=0.95. The collected data is analysed as Average, Frequency, Standard Deviation, T-test, ANOVA, Pearson Correlation Coefficient, Duncan multifulrange test by use of SPSS /PC (V7.5). The results of this study is summarized as under. 1. Every characteristics of subject is which the party of mother is 28.70age(±7.48) in the average ages, 51% in the high-school graduate, 38.5% in the christianity, total monthly income is 212.55 thousand won(±1.971), 74.5% in the housewife, 72.9% in the parents and children together living and the number of children to be 1.48person(± 0.6) in average, the recognition on the prognosis of baby is 74.0% in 'Don't know', the relationship with the husband after the hospitalization of babyis 37.3% in 'More Intimate', the relationship with the family of husband to be 48% in 'No-change', and the degree which is consulted with the husband about the baby is 55% in 'very frequently' and the visiting number per week is 4.59(±1.63) in average and the accompanying person in the time of visiting is which the number of husband is 56.3% and thus is the highest. The characteristics of baby is which the age is 21.88days(±16.47) after the birth in average, the sex to be 50 person in the female 52.1% and the order of birth to be 54.2% in the first chid, and the weight in the birth to be 2770gm(±610) and the height in the birth to be 46.26cm(±7.62) in aver age. The medical diagnosis is 37.5% in the premature infant, the career of hospitalization is 96.9% in 'None', and the operation plan is 90.6% in 'None' and the execution of operation is 88% in 'None' and the nursing of incubator is 55.2% in 'Yes', and the method of feeding is 50.5% in 'Oral' and the contents of feeding is 46.9% in the 'Milk'. 2. The total stress degree of subject is almost highly shown to be as 3.36(±0.86). If it is compared upon each cause, 'stress on disease status & prognosis' is highest 3.79(±1.28), and it is in the order of 'stress on medical treatment & nursing procedures' 3.70(±0.93), 'stress on hospital environment' 3.14(±0.86), 'stress on role of parents' 3.18(±0.92) and 'stress on communication & inter personal relationship' 2.62(± 0.77) 3. As the results of checking the notworthiness of stress degree upon each variable of subject, the variable showing the noted difference was the birth weight(γ=-0.16, P=0.04), birth height(γ=-0.23, P=0.03), nursing in the incubator(F=8.93, P=0.04), feed method(F=2.94, P=0.04). That is to say, it is shown which the smaller the birth weight is, the higher the stress degree of mother is noteworthily. Also, the smaller the birth height baby is, the higher the stress of mother is. In the incubator, it os shown which the mother whose baby is nursing in the incubator is higher in the stress degree than other mothers. Upon the feeding method of baby, that is to say, TPNis the highest, and it is shown in the order of NPO, Tube feeding, and P.O. feeding. When we review the above-mentioned results, as the status is serious, it is thought which we include the supporting nursing for coping with the stress of parents in the setting-up od nursing plan for the baby in the NICU.

• KDI Journal of Economic Policy
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• v.13 no.1
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• pp.3-33
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• 1991

Since the early 1980's, the Korean government has gradually been widening the Korean market to foreign consumer goods. This, combined with the increased purchasing power of the Korean consumers resulting from the continued economic growth of the country, has sparked a spectacular influx of foreign consumer goods into Korea, ranging from BMW's to chopsticks. Import of foreign consumer goods amounted to more than 6 billion dollars in 1989 and is continuing to grow at a rapid rate. The increased import of foreign consumer goods doubtlessly improved the overall welfare of the Korean consumers by providing them with a wider range of options to choose from, by lowering the prices of some of the consumer goods domestically produced, and also by forcing the producers of some Korean goods to face competition with better foreign goods, thus giving them an incentive to raise the quality of their products. However, it is agreed by most economists that this increase in general welfare has been much smaller than what they had expected at the outset. Consumer prices of most imported consumer goods are easily double the import price, and in some cases, more than treble the import prices. Further, there has not been a noticeable drop in the prices of domestically produced consumer goods. Much of the blame has been attributed to the distribution sector of Korea. The objective of this paper is to analyze the imported consumer goods distribution sector of Korea, focusing on the possible sources of the poor performance of that sector, and to make policy suggestions that could potentially increase the welfare. This paper differs from all the previous research by others on this subject in that it analyzes the imported consumer goods distribution sector of Korea as a vertical structure. The distribution sector of an imported consumer good is a vertical structure since it consists of an international market, an import stage, and domestic wholesale and retail markets, in that order vertically. Our study naturally includes the analysis of the vertical restraints as well as the analysis of the industrial organization of each horizontal stage in the vertical structure. Each horizontal component of the imported consumer goods distribution sector is basically a monopolistically competitive market differentiated by characteristics of goods and by the locations and the services of firms. Further, restrictive dealership and resale price maintenance are found to be widely in use. Our main findings are the follwing; First, most consumer goods are imported monopolistically or oligopolistically through restrictive dealership contracts between foreign producers and domestic importers. Such restrictive dealership gives importers market power in the domestic market and explains many of the large discrepancies betwen the consumer prices and the import prices of many goods. Korean anti - trust law does not cover the issues arising from the market power of an importer resulting from a restrictive dealership contract. Second, some major producers of Korean goods are also importers of foreign goods that are substitutes of their products. The import of substitutes by major domestic producers is anti - competitive because it tends to raise the prices of both domestic goods and foreign goods, and also because it reduces the incentive of the domestic producers to raise the quality of their products. Third, wholesalers and retailers widely use resale price maintenance as a price fixing mechanism, and while this is against the anti- trust law, it seldom gets noticed. Fourth, the high level of rents of real estate for commercial use works as an entry barrier to the distribution sector and results in reduced competition by the firms in that sector. Finally, there are information problems. Consumers have inferior information to firms about the quality of a foreign consumer good that they have not tried before. Such information asymmetry often enables firms to raise prices. In addition, information asymmetry between importers frequently delays the import of cheaper substitutes. In order to alleviate the problems indentified above, we suggest the following policy changes. The government should strengthen the anti - trust law and its enforcement to regulate restrictive import contracts, import of competing goods by major domestic producers, and RPM by wholesalers and retailers that is aimed at price fixing. In addition, the government should loosen its tight real estate policy to encourage investment in the distribution sector. Finally, we suggest that the import price revelation policy that has been in use for some items since 1990 be expanded to most imported consumer goods that are introduced for the first time to give consumer better information and be used only for the period of time needed to inform sufficient number of consumers.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.909-919
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• 2010

The purpose of this study was to investigate the demand and use of fresh-cut produce in school foodservice and restaurant industries. The subjects of this survey study were 200 school nutritionists and 70 cooks or managers in the restaurant industry nationwide. The data were collected by means of self-administered or e-mail questionnaires. Data analysis was completed using the SPSS window (ver. 12.0) program including frequency, $\chi^2$-test and t-test. Survey questions assessed the general characteristic of respondents, and the supply, use, and demand of fresh-cut produce in school foodservice and restaurant industries. Over 74% of the subjects have used fresh-cut produce. Most of the school foodservice (84.0%) kept fresh-cut produce for one day, while restaurant industry (28.3%) kept them up to three days. The nutritionists of school foodservice and managers of restaurant industry considered origin and date of production as the most important factor, respectively, when fresh-cut produce were being used. Fresh-cut root vegetable, such as potato and carrot was used mostly. The main reason not to use the fresh cut produce was due to the distrust of the fresh-cut produce safety in school foodservice and cost in restaurant industry. The main problem in fresh-cut produce use was the need of rewashing (29.9%) in school foodservice and irregular size (39.0%) in restaurant industry. These results indicate that the quality standard and size specification must be prepared with production guideline of safe fresh-cut produce.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.7
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• pp.858-868
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• 2008

This study was carried out to investigate the effects of Gastrodiae Rhizoma powder on plasma lipid profiles in elderly volunteers with hyperlipidemia, hypertension, diabetes or heart disease. 32 elderly people, 11 males and 21 females aged $60{\sim}77$ years, were given Gastrodiae Rhizoma powder 15 g twice daily for 6 months. We investigated the antheropometric data, general characteristics and dietary habit by using questionnaires. Fasting blood samples were collected from the subjects before and after this 6 months intervention study. Blood pressure, glucose, hemoglobin and lipid levels of plasma, atherogenic index (AI) and cardiac risk factors (CRF, LHR, HTR) were determined before and after consumption of Gastrodiae Rhizoma powder. The mean body mass index (BMI) of the male and female subjects were 22.4 and 23.6, respectively. The percent of ideal body weight (PIBW) of males and females were 105.6% and 122.3%, respectively. The subjects had decreased intake frequency of fish and meat in their dietary habit. After consumption of Gastrodiae Rhizoma powder, there were no significant differences in blood pressure; however, the blood glucose significantly decreased with Gastrodiae Rhizoma intake in the males. In the subjects, the levels of plasma total cholesterol, triglyceride, and LDL-cholesterol were decreased by the consumption of Gastrodiae Rhizoma powder; while the levels of plasma LDL-cholesterol was significantly decreased in female. Blood pressure and biochemical assessment (blood glucose, hemoglobin, triglyceride, total cholesterol, LDL and HDL-cholesterol) of the subjects were within the normal range. It was found that AI, CRF and LHR were significantly decreased by Gastrodiae Rhizoma intake. The present results indicate that dietary supplementation of Gastrodiae Rhizoma improved lipid metabolism and cardiac risk factor in cardiovascular disease.

• Korean Journal of Environmental Agriculture
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• v.13 no.3
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• pp.321-337
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• 1994

The garbage from the dwelling houses was composted in two kinds of small composter in laboratory to investigate the possibility of garbage composting. They were general small composters. One (type 1) was insullated but the other (type 2) was not. Because it was found that type 2 was not available for composting under our meteorological conditions through winter experiment, only type 1 was tested in spring and summer. The experiment was performed for 8 weeks in each season. The seasonal variation of several compounds in compost was evaluated and discussed. The result summarized belows are those taken at the end of the experiment, if the time was not specified. 1) The maximum temperature was $58^{\circ}C$ in spring, $57^{\circ}C$ in summer and $41^{\circ}C$ in winter. This temperature was enough to destroy the pathogen except for winter. 2) The mass was reduced to average 62.5% and the volume reduction was avergae 74%. 3) The density was estimated as 0.7kg/l in spring, 0.8kg/l in summer and 1.1kg/l in winter. 4) The water content was not much changed for composting periods. It had 75.6% in spring and 76.6% in summer and winter. 5) There was a great seasonal difference in pH value. It was reached to pH 6.13 in spring, pH 8.62 in summer and pH 4.75 in winter. 6) The faster organic matter was decomposed, the greater ash content was increased. Cellulose and lignin content were increased, but hemicellulose content was reduced during composting period. 7) Nitrogen contents were in the range of 3.1-5.6% and especially high in summer. After ammonium nitrogen contents were increased at the early stage of composting period, they were decreased. The maximum ammonium nitrogen content was 3,243mg/kg after 2 weeks in winter, 6,053mg/kg after 3 weeks in spring and 30,828mg/kg after 6 weeks in summer. C/N-ratios were not much changed. Nitrification occurred actively in spring and summer. 8) The contents of volatile and higher fatty acids were increased in early stage of composting and reduced after that. The maximum content of total fatty acid was 10.1% after 2 weeks in winter, 5.8% after 2 weeks in spring and 15.7% after 4 weeks in summer. 9) The contents of inorganic compounds were not accumulated as composting was proceeded. They were in the range of 0.9-4.4% $P_2O_5$, 1.6-2.9% $K_2O$, 2.4-4.6% CaO and 0.30-0.80% MgO. 10) CN and heavy metal contents did not show any tendency. They were in the range of 0.11-28.99mg/kg CN, 24-166mg/kg Zn, 5-129mg/kg Cu, 0.8-14.3mg/kg Cd, 7-42mg/kg Pb, ND-30mg/kg Cr and $ND-132.16\;{\mu}g/kg$ Hg.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.18
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• pp.54-87
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• 1975

The effects of various weather factors on yield components of rice, year variation of yield components within regions, and regional differences of yield components within year were investigated at three Crop Experiment Stations O.R.D., Suweon, Iri, Milyang, and at nine provincial Offices of Rural Development for eight years from 1966 to 1973 for the purpose of providing information required in improving cultural practices and predicting the yield level of rice. The experimental results analyzed by standard partial regression analysis are summarized as follows: 1. When rice was grown in ordinary seasonal culture the number of panicles greatly affected rice yield compared to other yield components. However, when rice was seeded in ordinary season and transplanted late, and transplanted in ordinary season in the northern area the ratio of ripening was closely related to the rice yield. 2. The number of panicles showed the greatest year variation when the Jinheung variety was grown in the northern area. The ripening ratio or 1, 000 grain weight also greatly varied due to years. However, the number of spikelets per unit area showed the greatest effects on yield of the Tongil variety. 2. Regional variation of yield components was classified into five groups; 1) Vegetation dependable type (V), 2) Partial vegetation dependable type (P), 3) Medium type (M), 4) Partial ripening dependable type (P.R), and 5) Ripening dependable type (R). In general, the number of kernel of rice in the southern area showed the greatest partial regression coefficient among yield components. However, in the mid-northern part of country the ripening ratio was one of the component!; affecting rice yield most. 4. A multivariate equation was obtained for both normal planting and late planting by log-transforming from the multiplication of each component of four yield components to additive fashion. It revealed that a more accurate yield could be estimated from the above equation in both cases of ordinary seasonal culture and late transplanting. 5. A highly positive correlation coefficient was obtained between the number of tillers from 20 days after transplanting and the number of panicles at each(tillering) stage 20 days after transplanting in normal planting and late planting methods. 6. A close relationship was found between the number of panicles and weather factors 21 to 30 days, after transplanting. 7. The average temperature 31 to 40 days after transplanting was greatly responsible for the maximum number of tillers while the number of duration of sunshine hours per day 11 to 30 days after transplantation was responsible for that character. The effect of water temperature was negligible. 8. No reasonable prediction for number of panicles was calculated from using either number of tillers or climatic factors. The number of panicles could early be estimated formulating a multiple equation using number of tillers 20 days after transplantation and maximum temperature, temperature range and duration of sunshine for the period of 20 days from 20 to 40 days after transplantation. 9. The effects of maximum temperature and day length 25 to 34 days before heading, on kernel number per panicle, were great in the mid-northern area. However, the minimum temperature and day length greatly affected the kernel number per panicle in the southern area. The maximum temperature had a negative relationship with the kernel number per panicle in the southern area. 10. The maximum temperature was highly responsible for an increased ripening ratio. On the other hand, the minimum temperature at pre-heading and early ripening stages showed an adverse effect on ripening ratio. 11. The 1, 000 grain weight was greatly affected by the maximum temperature during pre- or mid-ripening stage and was negatively associated with the minimum temperature over the entire ripening period.

• Asia pacific journal of information systems
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• v.24 no.2
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• pp.211-232
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• 2014

Recently, there is a growing interest toward social commerce using SNS(Social Networking Service), and the size of its market is also expanding due to popularization of smart phones, tablet PCs and other smart devices. Accordingly, various studies have been attempted but it is shown that most of the previous studies have been conducted from perspectives of the users. The purpose of this study is to derive user-centered CSF(Critical Success Factor) of social commerce from the previous studies and analyze the CSF perception gap between social commerce service providers and users. The CSF perception gap between two groups shows that there is a difference between ideal images the service providers hope for and the actual image the service users have on social commerce companies. This study provides effective improvement directions for social commerce companies by presenting current business problems and its solution plans. For this, This study selected Korea's representative social commerce business Ticket Monster, which is dominant in sales and staff size together with its excellent funding power through M&A by stock exchange with the US social commerce business Living Social with Amazon.com as a shareholder in August, 2011, as a target group of social commerce service provider. we have gathered questionnaires from both service providers and the users from October 22, 2012 until October 31, 2012 to conduct an empirical analysis. We surveyed 160 service providers of Ticket Monster We also surveyed 160 social commerce users who have experienced in using Ticket Monster service. Out of 320 surveys, 20 questionaries which were unfit or undependable were discarded. Consequently the remaining 300(service provider 150, user 150)were used for this empirical study. The statistics were analyzed using SPSS 12.0. Implications of the empirical analysis result of this study are as follows: First of all, There are order differences in the importance of social commerce CSF between two groups. While service providers regard Price Economic as the most important CSF influencing purchasing intention, the users regard 'Trust' as the most important CSF influencing purchasing intention. This means that the service providers have to utilize the unique strong point of social commerce which make the customers be trusted rathe than just focusing on selling product at a discounted price. It means that service Providers need to enhance effective communication skills by using SNS and play a vital role as a trusted adviser who provides curation services and explains the value of products through information filtering. Also, they need to pay attention to preventing consumer damages from deceptive and false advertising. service providers have to create the detailed reward system in case of a consumer damages caused by above problems. It can make strong ties with customers. Second, both service providers and users tend to consider that social commerce CSF influencing purchasing intention are Price Economic, Utility, Trust, and Word of Mouth Effect. Accordingly, it can be learned that users are expecting the benefit from the aspect of prices and economy when using social commerce, and service providers should be able to suggest the individualized discount benefit through diverse methods using social network service. Looking into it from the aspect of usefulness, service providers are required to get users to be cognizant of time-saving, efficiency, and convenience when they are using social commerce. Therefore, it is necessary to increase the usefulness of social commerce through the introduction of a new management strategy, such as intensification of search engine of the Website, facilitation in payment through shopping basket, and package distribution. Trust, as mentioned before, is the most important variable in consumers' mind, so it should definitely be managed for sustainable management. If the trust in social commerce should fall due to consumers' damage case due to false and puffery advertising forgeries, it could have a negative influence on the image of the social commerce industry in general. Instead of advertising with famous celebrities and using a bombastic amount of money on marketing expenses, the social commerce industry should be able to use the word of mouth effect between users by making use of the social network service, the major marketing method of initial social commerce. The word of mouth effect occurring from consumers' spontaneous self-marketer's duty performance can bring not only reduction effect in advertising cost to a service provider but it can also prepare the basis of discounted price suggestion to consumers; in this context, the word of mouth effect should be managed as the CSF of social commerce. Third, Trade safety was not derived as one of the CSF. Recently, with e-commerce like social commerce and Internet shopping increasing in a variety of methods, the importance of trade safety on the Internet also increases, but in this study result, trade safety wasn't evaluated as CSF of social commerce by both groups. This study judges that it's because both service provider groups and user group are perceiving that there is a reliable PG(Payment Gateway) which acts for e-payment of Internet transaction. Accordingly, it is understood that both two groups feel that social commerce can have a corporate identity by website and differentiation in products and services in sales, but don't feel a big difference by business in case of e-payment system. In other words, trade safety should be perceived as natural, basic universal service. Fourth, it's necessary that service providers should intensify the communication with users by making use of social network service which is the major marketing method of social commerce and should be able to use the word of mouth effect between users. The word of mouth effect occurring from consumers' spontaneous self- marketer's duty performance can bring not only reduction effect in advertising cost to a service provider but it can also prepare the basis of discounted price suggestion to consumers. in this context, it is judged that the word of mouth effect should be managed as CSF of social commerce. In this paper, the characteristics of social commerce are limited as five independent variables, however, if an additional study is proceeded with more various independent variables, more in-depth study results will be derived. In addition, this research targets social commerce service providers and the users, however, in the consideration of the fact that social commerce is a two-sided market, drawing CSF through an analysis of perception gap between social commerce service providers and its advertisement clients would be worth to be dealt with in a follow-up study.

• Korean Journal of Food Science and Technology
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• v.8 no.1
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• pp.19-32
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• 1976

The laboratory Mejus as well as home-made Meju and improved Meju received from Korea were ripened in the brine for up to 8 months and the changes is the chemical composition during the process were determined and the differences between the types of Meju were compared. On the basis of the amino acid pattern, the changes in the protein quality of soybean during the process was evaluated. No significant changes in the general chemical composition of Meju were noticed during the ripening for 8 months. However, the nitrogen solubility of Meju increased for $13{\sim}29%$ to $66{\sim}78%$ during 8 month ripening of the Meju-brine mixture. The concentration of free amino-N to the total-N increased from $4{\sim}7%$ in Meju to $29{\sim}35%$ in the 8month ripened mixture. The concentration of amino-N to the total-N increased from $1{\sim}4%$ in Meju to $5{\sim}14%$ in the 8month ripened mixture and the changes varied with the type of Meju used. Remarkable changes in the amino acid pattern of soybean were occured during the ripening process. The concentration of methionine decreased to the half of original Meju during the first month of ripening. Arginine and histidine were destroyed rapidly by the ripening longer than 1 month. A considerable amount of ornithine was synthesized during the ripening. The amino acid pattern of Meju did change drastically during the ripening longer than 3 months and the changes varied with the type of Meju. The retention of the nutrients in soybean during 8 month ripening of the laboratory 3 month Meju in the brine was 49% for carbohydrates, 107% for crude fat, 93% for crude protein and 74% for the total amino acid. Histidine, arginine and methionine and 74% for the total amino acid. Histidine, arginine and methionine were the most damaged during the process, retaining only 25%, 27% and 49% of the contents in raw soybean, respectively, whereas lysine retained 79%. By the separation of the 8 month ripened mixture, approximately 60% of crude protein, all of crude fat and 80% of carbohydrates in the mixture were retained in soypaste. Soypaste contained higher concentrations of amino acids per 16gN compared to soysauce, except for lysine. The most limiting amino acid of the protein was the S-containing amino acids in all cases studied, whereas the second limiting amino acid varied from valine in soybean to threonine in most of Mejus and the brine mixtures, lysine in most of soypastes and tryptophan in some of soysauces. According to the protein quality evaluation made by the reference of the FAO provisional pattern of amino acid, the chemical score of raw soybean was 82, which was reduced to 77 by cooking and further reduced to $71{\sim}74$ by Meju fermentation. At the eighth month of ripening the chemical score of the Meju-brine mixtures were reduced to $51{\sim}66. After the separation, the chemical score of soypaste ranged from 60 to 71, whereas that of soysauce varied from 45 to 57. Generally, the products made from improved Meju recorded the highest score, whereas those made from homemade Meju showed the poorest protein quality. The essential amino acid index(EAAI) of the samples was similar to the chemical score, but it appeared to fit the overall changes in the amino acid pattern during the process better than the chemical score.

• Parasites, Hosts and Diseases
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• v.27 no.4
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• pp.231-248
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• 1989

The growth and development of the metacercariae of F. seoulensis cultivated in vitro or on the chick chorioallantois were assessed by comparison with the optimum process of maturation in albino rats and new born chickens. The process of maturation was divided for convenience into six stages: Stage 1 ; cell multiplication, Stage 2; body shaping, Stage 3; separation of genital anlagen, Stage :1 organogeny, Stage 5; gametogony, and Stage 6: oviposition. In Hank's and Tyrode's .solutions, the metacercariae were alive up to 200 days or more at $4^{\circ}C$ without any development. The in vivo maturation process in rats or chicks was as follows: stage 1 from 6 hours; stage 2 from 24 hours; stage 3 from 48 to 72 hours; stage 4 from 3 to 4 days; stage 5 from 4 to 5 days; and stage 6 from 5 to 8 days. Despite unsuccessful infection of the metacercariae to 12 day old chicks, fully mature worms of stage 5 or 6 were recovered from new born chicks (1 to 2 days old), The metacercariae of F. seoulensis grown in vitro were up to stage 3 and no further maturation was observed. Of various media employed, the medium NCTC 109 (Gibco) or NCTC 135(Gibco) supplemented with 20% egg yolk or 20% whole egg macerate or 0.5% yeast was basically required for the earlier development of the fluke. It took 16.1 days(in average) to reach the stage 3 after cultivation. The metacercariae cultivated on the chorioallantoic membranes of 6∼13 day old chick embryo at 37∼38℃ showed their full development up to stage 5 or 6. However, the worms were in general remarkably retarded, compared with those grown in rats or chickens. In the experiments of worm transplant, although the transfer was failed from in vitro culture to in vivo of rats(Per os), the transplants from in vitro culture to the chorioallantois and from the choriollantois to in vivo of rat host were successful with or without development of the transferred worms. In the present study, it was observed that the metacercariae of F, seoulensis can be maintained in vitro media with poor development as well as fully matured in 1 to 2 day-old chicks or on the chorioallantois at a very low rate.

• Korean Journal of Weed Science
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• v.2 no.1
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• pp.31-40
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• 1982

For the effective control of weeds in mechanically transplanted paddy field weeding effects of naproanide ${\alpha}$-(${\beta}$-naphthoxy) propion anilide], pyrazolate [4-2, 4-dichlorobenzoyl)-1, 3-dimethyl pyrazol-5-yl-p-tolune sulphanate], chlormethoxynil (2, 4-dichloro-phenyl-4-nitro-3-methoxy phenyl ether), SL-49 [1-3dimethyl-4(2, 4dichlorobenzoyl)-5-phenacyloxy pyrazole], ACN (3-chloro-2-amino-l, 4-naphthoquinone) either alone or in combination with butachlor (2-chlor-2, 6-diethyl-N-buthoxymethyl acetanilide) were compared. Pyrazolate and SL-49 were most effective for the control of Sagittaria pygmaea MIQ. and Potomogeton distinctus A. BENN. including most annual weeds. Weeding effect of butachlor alone was very high for annuals, good for Cyperus serotinus ROTTB. and poor for S. pygmaea and P. distinctus. But the weeding effect of the combination of butachlor and pyrazolate was stronger than that of butachlor alone and therefore this mixture was effective for S. pygmaea, P. distinctus and C. serotinus including all the annual weeds. The combination of butachlor and SL-49 showed the same tendency as the combination of butachlor and pyrazolate. Naproanilide was not effective for the control of Echinochlor crusgalli P. BEAUV and less effective for Monochoria vaginalis PRESL, but excellent for S. pygmaea. By mixing butachlor with naproanilide weeding, spectrum for annuals and S. pygmaea was much increased by that for P. distinctus and C. serotinus was not satisfactory. ACN was not satisfactory for the control of all the tested weeds but the weeding effect was increased in general by mixing with butachlor. Chlormethoxynil was excellent for the control of annual weeds but it has no effect on C. serotinus, S. pygmaea and P. distinctus showing some initial controling effect but these weeds regrew afterwards. The weeding activity of ACN increased in combination with butachlor and the residual activity was stronger than that of ACN alone. A light crop injury was found at the initial period after treatments in all treated plots. The yield from all treated plots except those from plots treated with ACN, butachlor and naproanilide were not significantly different from the band weeded plot.