• Title/Summary/Keyword: Success Factor

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ATHEROSCLEROSIS, CHOLESTEROL AND EGG - REVIEW -

  • Paik, I.K.;Blair, R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.9 no.1
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    • pp.1-25
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    • 1996
  • The pathogenesis of atherosclerosis can not be summarized as a single process. Lipid infiltration hypothesis and endothelial injury hypothesis have been proposed and investigated. Recent developments show that there are many points of potential interactions between them and that they can actually be regarded as two phases of a single, unifying hypothesis. Among the many risk factors of atherosclerosis, plasma homocysteine and lipoprotein(a) draw a considerable interest because they are independent indicators of atherogenicity. Triglyceride (TG)-rich lipoproteins (chylomicron and VLDL) are not considered to be atherogenic but they are related to the metabolism of HDL cholesterol and indirectly related to coronary heart disease (CHD). LDL can of itself be atherogenic but the oxidative products of this lipoprotein are more detrimental. HDL cholesterol has been considered to be a favorable cholesterol. The so-called 'causalist view' claims that HDL traps excess cholesterol from cellular membranes and transfers it to TG-rich lipoproteins that are subsequently removed by hepatic receptors. In the so-called 'noncausalist view', HDL does not interfere directly with cholesterol deposition in the arterial wall but instead reflects he metabolism of TG-rich lipoproteins and their conversion to atherogenic remnants. Approximately 70-80% of the human population shows an effective feedback control mechanism in cholesterol homeostasis. Type of dietary fat has a significant effect on the lipoprotein cholesterol metabolism and atherosclerosis. Generally, saturated fatty acids elevate and PUFA lower serum cholesterol, whereas MUFA have no specific effect. EPA and DHA inhibit the synthesis of TG, VLDL and LDL, and may have favourable effects on some of the risk factors. Phospholipids, particularly lecithin, have an antiatherosclerotic effect. Essential phospholipids (EPL) may enhance the formation of polyunsaturated cholesteryl ester (CE) which is less sclerotic and more easily dispersed via enhanced hydrolysis of CE in the arterial wall. Also, neutral fecal steroid elimination may be enhanced and cholesterol absorption reduced following EPL treatment. Antioxidants protect lipoproteins from oxidation, and cells from the injury of toxic, oxidized LDL. The rationale for lowering of serum cholesterol is the strong association between elevation of plasma or serum cholesterol and CHD. Cholesterol-lowing, especially LDL cholesterol, to the target level could be achieved using diet and combination of drug therapy. Information on the link between cholesterol and CHD has decreased egg consumption by 16-25%. Some clinical studies have indicated that dietary cholesterol and egg have a significant hypercholesterolemic effect, while others have indicated no effect. These studies differed in the use of purified cholesterol or cholesterol in eggs, in the range of baseline and challenge cholesterol levels, in the quality and quantity of concomitant dietary fat, in the study population demographics and initial serum cholesterol levels, and clinical settings. Cholesterol content of eggs varies to a certain extent depending on the age, breed and diet of hens. However, egg yolk cholesterol level is very resistant to change because of the particular mechanism involved in yolk formation. Egg yolk contains a factor of factors responsible for accelerated cholesterol metabolism and excretion compared with crystalline cholesterol. One of these factors could be egg lecithin. Egg lecithin may not be as effective as soybean lecithin in lowering serum cholesterol level due probably to the differences of fatty acid composition. However, egg lecithin may have positive effects in hypercholesterolemia by increasing serum HDL level and excretion of fecal cholesterol. The association of serum cholesterol with egg consumption has been widely studied. When the basal or control diet contained little or no cholesterol, consumption of 1 or 2 eggs daily increased the concentration of plasma cholesterol, whereas that of the normolipemic persons on a normal diet was not significantly influenced by consuming 2 to 3 eggs daily. At higher levels of egg consumption, the concentration of HDL tends to increase as well as LDL. There exist hyper-and hypo-responders to dietary (egg) cholesterol. Identifying individuals in both categories would be useful from the point of view of nutrition guidelines. Dietary modification of fatty acid composition has been pursued as a viable method of modifying fat composition of eggs and adding value to eggs. In many cases beneficial effects of PUFA enriched eggs have been demonstrated. Generally, consumption of n-3 fatty acids enriched eggs lowered the concentration of plasma TG and total cholesterol compared to the consumption of regular eggs. Due to the highly oxidative nature of PUFA, stability of this fat is essential. The implication of hepatic lipid accumulation which was observed in hens fed on fish oils should be explored. Nutritional manipulations, such as supplementation with iodine, inhibitors of cholesterol biosynthesis, garlic products, amino acids and high fibre ingredients, have met a limited success in lowering egg cholesterol.

The Analysis for the Regulation related to Chinese Online Game Review -Focused on NHN Chinese Game- (중국 온라인 게임 심의에 관한 규제 분석 -중국 NHN 게임을 중심으로-)

  • Song, Seung-Keun;Kim, Chee-Yong
    • The Journal of the Korea Contents Association
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    • v.9 no.11
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    • pp.151-162
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    • 2009
  • The objective of this study is to uncover the standard and procedure of the review for the online game to export to China and try to find a plan how to solve a problem such as regulation for the online game imported into China depending on a protective policy for homemade game. The literatures related to the policy of China online game industry and the present condition of the wholistic restriction are reviewed and the standard and procedure of the review of China online game which is veiled was able to find definitely by using the case study on Korean company which was a great success as localization in China. As a result of this study, we found that the key factor on the review standard of China online game is the anti-social personality, such as 'the overthrow of Chinese socialist system', 'the territorial issue as the eviction of Hong Kong or the acknowledgment of Taiwan government', 'independence problem of the minorities', and 'damage to property as national treasure', et cetera. While the review of the homemade game in China takes about a month through just two steps in review process on online game, that of foreign game is required over at least three months through four steps in it. Moreover, it is difficult for foreign games to obtain the license due to total amount regulation for online game by 'General Administration of Press and Publication of the People's the Republic of China'. In the case of the joint-venture company, it is most important to the smooth communication between Korean company and Chinese company in order to overcome these strong regulation for online game review in China. Furthermore, as Chinese company in outward appearance it is need to be positioned absolutely in Chinese marketplace. The definite positioning strategy enables foreign companies to avoid the strong regulation about the foreign game in China. To understand, finally, deeply politics, society, and culture presented in Chinese ethics textbook permits the foreign companies to predict the exact standard of the review for online game. Therefore, this study is concluded with key implications to sustain guidelines on the deliberation for foreign companies which want to export online game to China to improve the predictability and accountableness about the review of the online game in China.

EEPERF(Experiential Education PERFormance): An Instrument for Measuring Service Quality in Experiential Education (체험형 교육 서비스 품질 측정 항목에 관한 연구: 창의적 체험활동을 중심으로)

  • Park, Ky-Yoon;Kim, Hyun-Sik
    • Journal of Distribution Science
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    • v.10 no.2
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    • pp.43-52
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    • 2012
  • As experiential education services are growing, the need for proper management is increasing. Considering that adequate measures are an essential factor for achieving success in managing something, it is important for managers to use a proper system of metrics to measure the performance of experiential education services. However, in spite of this need, little research has been done to develop a valid and reliable set of metrics for assessing the quality of experiential education services. The current study aims to develop a multi-item instrument for assessing the service quality of experiential education. The specific procedure is as follows. First, we generated a pool of possible metrics based on diverse literature on service quality. We elicited possiblemetric items not only from general service quality metrics such as SERVQUAL and SERVPERF but also from educational service quality metrics such as HEdPERF and PESPERF. Second, specialist teachers in the experiential education area screened the initial metrics to boost face validity. Third, we proceeded with multiple rounds of empirical validation of those metrics. Based on this processes, we refined the metrics to determine the final metrics to be used. Fourth, we examined predictive validity by checking the well-established positive relationship between each dimension of metrics and customer satisfaction. In sum, starting with the initial pool of scale items elicited from the previous literature and purifying them empirically through the surveying method, we developed a four-dimensional systemized scale to measure the superiority of experiential education and named it "Experiential Education PERFormance" (EEPERF). Our findings indicate that students (consumers) perceive the superiority of the experiential education (EE) service in the following four dimensions: EE-empathy, EE-reliability, EE-outcome, and EE-landscape. EE-empathy is a judgment in response to the question, "How empathetically does the experiential educational service provider interact with me?" Principal measures are "How well does the service provider understand my needs?," and "How well does the service provider listen to my voice?" Next, EE-reliability is a judgment in response to the question, "How reliably does the experiential educational service provider interact with me?" Major measures are "How reliable is the schedule here?," and "How credible is the service provider?" EE-outcome is a judgmentin response to the question, "What results could I get from this experiential educational service encounter?" Representative measures are "How good is the information that I will acquire form this service encounter?," and "How useful is this service encounter in helping me develop creativity?" Finally, EE-landscape is a judgment about the physical environment. Essential measures are "How convenient is the access to the service encounter?,"and "How well managed are the facilities?" We showed the reliability and validity of the system of metrics. All four dimensions influence customer satisfaction significantly. Practitioners may use the results in planning experiential educational service programs and evaluating each service encounter. The current study isexpected to act as a stepping-stone for future scale improvement. In this case, researchers may use the experience quality paradigm that has recently arisen.

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A study of DISC Behaviour Patterns on the satisfaction difference of Comic-Animation Department students : Focusing on satisfaction in the major and satisfaction of the university life (DISC 행동유형에 따른 만화애니메이션학과 대학생들의 만족도 차이 연구 - 전공만족도와 대학생활만족도를 중심으로)

  • Kim, Shin
    • Cartoon and Animation Studies
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    • s.47
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    • pp.217-239
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    • 2017
  • The purpose of this research is to maximize the core competencies by objectively measuring the Behaviour Patterns of students in Comic-Animation major to understand the difference between individuals and to maximize one's merits which will improve the efficiency in education. Also through this research we could understand which aspects would be affected in both the satisfaction about the major based on Behaviour Patterns and the satisfaction of university life. According to the DISC Patterns, 41.7% of the students in Comic-Animation department shows that they were in Patterns I (Influence). And Patterns S (Steadiness) were 10% which was the lowest percentage in this survey. In the average of the subject's satisfaction aspect, the satisfaction of the professors' suggestion was 3.68 which was the highest. While the satisfaction of the administration service and welfare facility was 2.56 which was the lowest. The satisfaction rate based on DISC Behaviour Patterns shows a significant difference among the satisfaction of the department, the satisfaction of atmosphere in university and the satisfaction of the admin and welfare. Patterns I (Influence) was the highest the satisfaction in the major and the satisfaction of the university life while Patterns C(Criticalness) was the lowest. In particular, the importance of the I (Influence) is the most important factor, but it is essential that there is a slight decrease in the precision and accuracy of the work, and C(Criticalness) is shy and stressed, so they need to give positive communication and accurate advice. It is required to Comic-Animation department professor to analyse students' character based on Behaviour Patterns and a person's pros and cons for the career exploration and the employment consultation in order to have positive affect on employment rate. Also if the department's Behaviour Patterns construction were well utilized, it can improve the success rate of useful leadership and fellowship. it will improve the atmosphere in the department which will decrease the drop-out rate but increase the cohesion in the department which will lead to providing better result in the work and the project.

The Comparison of Existing Synthetic Unit Hydrograph Method in Korea (국내 기존 합성단위도 방법의 비교)

  • Jeong, Seong-Won;Mun, Jang-Won
    • Journal of Korea Water Resources Association
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    • v.34 no.6
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    • pp.659-672
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    • 2001
  • Generally, design flood for a hydraulic structure is estimated using statistical analysis of runoff data. However, due to the lack of runoff data, it is difficult that the statistical method is applied for estimation of design flood. In this case, the synthetic unit hydrograph method is used generally and the models such as NYMO method, Snyder method, SCS method, and HYMO method have been widely used in Korea. In this study, these methods and KICT method, which is developed in year 2000, are compared and analyzed in 10 study areas. Firstly, peak flow and peak time of representative unit hydrograph and synthetic unit hydrograph in study area are compared, and secondly, the shape of unit hydrograph is compared using a root mean square error(RMSE). In Nakayasu method developed in Japan, synthetic unit hydrograph is very different from peak flow, peak time, and the shape of representative unit hydrograph, and KICT method(2000) is superior to others. Also, KICT method(2000) is superior to others in the aspects of using hydrologic and topographical data. Therefore, Nakayasu method is not a proper in hydrological practice. Moreover, it is considered that KICT model is a better method for the estimation of design flood. However, if other model, i.e. SCS method, Nakayasu method, and HYMO method, is used, parameters or regression equations must be adjusted by analysis of real data in Korea.

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Examining the Relationships among Attitude toward Luxury Brands, Customer Equity, and Customer Lifetime Value in a Korean Context (측시이한국위배경적사치품패태도(测试以韩国为背景的奢侈品牌态度), 고객자산화고객종신개치지간적관계(顾客资产和顾客终身价值之间的关系))

  • Kim, Kyung-Hoon;Park, Seong-Yeon;Lee, Seung-Hee;Knight, Dee K.;Xu, Bing;Jeon, Byung-Joo;Moon, Hak-Il
    • Journal of Global Scholars of Marketing Science
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    • v.20 no.1
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    • pp.27-34
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    • 2010
  • During the past 10 years, sales of luxury goods increased significantly to more than US$ 130 billion in 2007. In this industry, more than half of the revenue comes from Asia where the average income has risen significantly, and the demand for luxury products is forecast to grow rapidly. Purchasing luxury brands appears to be an intriguing social phenomenon that is profitable for companies in this region. As a newly developed country, Korea is one of the most attractive luxury markets in Asia. Currently, a total of 120 luxury fashion brands have entered the Korean market, primarily in luxury districts in Seoul where the competition is fierce. The purposes of this study are to: (1) identify antecedents of attitude toward luxury brands, (2) examine the effect of attitudes toward luxury brands on customer equity, (3) determine the impact of attitudes toward luxury brands on customer lifetime value, and (4) investigate the influence of customer equity on customer life time value. Previous studies have examined materialism, social need, experiential need, need for uniqueness, conformity, and fashion involvement as antecedents of attitude toward luxury brands. Richins and Dowson (1992) suggested that that materialism influences consumption behavior relative to quantity of goods purchased. Nueno and Quelch (1998) reported that the ownership of luxury brands conveys information related to the owner's social status, communicates an image of success and prestige, and is a determinant of purchase behavior. Experiential need is recognized as an important aspect of consumption, especially for new products developed to meet consumer demand. Since luxury goods, by definition are relatively scarce, ownership of these types of products may fulfill consumers' need for uniqueness. In this study, value equity, relationship equity, and brand equity are examined as drivers of customer equity. The sample (n = 114) was undergraduate and graduate students at two private women's universities in Seoul, Korea. Data collection was conducted using a self-administered questionnaire survey in March, 2009. Data analysis included descriptive statistics, factor analysis, reliability analysis, and regression analysis using SPSS 15.0 software. Data analysis resulted in a number of conclusions. First, experiential need and fashion involvement positively influence participants' attitude toward luxury brands. Second, attitude toward luxury brands positively influences brand equity, followed by value equity and relationship equity. However, there is no significant relationship between attitude toward luxury brand and customer lifetime value. Finally, relationship equity positively influences customer lifetime value. In conclusion, young consumers are an important potential consumer group that tries different brands to discover the ones most suitable for them. Luxury marketers that use effective marketing strategies to attract and engender loyalty among this potentially lucrative consumer group may increase customer equity and lifetime value.

A Study on University Students' Business Planning and Starting up a Business in Korea (우리나라 대학생들의 창업 및 사업계획에 대한 연구)

  • Koh, In-Kon
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.7 no.2
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    • pp.1-8
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    • 2012
  • Recently the youth starting up a business has become a buzzword. Business plan is a fundamentals in starting up a business. Therefore, in this study, I investigated the business planning behavior of university students in Korea. Especially, I investigated whether university students in Korea dealt with business plan inside and outside or not, and examined university students' thought whether corporate performance is related to business plan or not, and if any, how closely they are. Meanwhile, existing studies and books are arguing that there is a high correlation between business plan and corporate performance, however, there are not many domestic and/or foreign studies that analyzed it empirically. In order to find an answer to this problem, this study was approached empirically. First, the components of business plan were selected through an extensive literature review including existing researches and through factor analysis, I classified them into the five factors of product management, product development, management support system building, organizational management and macro planning. Also, I classified corporate performance into quantitative and qualitative performance, and investigated the influences of business plan factors on those performances. As a result, I found belows. First, university students in Korea thought that the business plan components affected the quantitative and qualitative performances of corporate positively. Second, Korean students had high interests in starting up a business and wanted to run a service business but had almost no experience of business planning. Whilst, Foreign students had relatively high interests in starting up a business and experiences of business planning. They wanted starting up in various industry also. Meanwhile, I did't find the gender differences in those aspects. In this study, I empirically investigated the relation between business plan components and corporate performances in the university students' view, not that of company. So I believe that this study can shed lights on the direction of effective starting up education for increasing the success rate of youth starting up a business.

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A Study on the Relationship Between the Performance of Venture Business and CEO's Characteristics (벤처기업 경영자 특성이 경영성과에 미치는 영향에 관한 연구;대덕연구개발특구를 중심으로)

  • Yoon, Bo-Hyun;Park, Joon-Byoung
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.2 no.3
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    • pp.145-168
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    • 2007
  • Current researches have been proceed on CEO's Characteristics of venture business because the CEO has considered as one of the important factors for the success of venture business. But prior research on the performance of venture business has produced inconsistently in terms of CEO's characteristics. The purpose of this study is to develop a comprehensive model for the relation between the performance and a type of CEO's characteristics by a growth process of venture business, which is the main subject of analysis in venture business. Also, this study analyzes various CEO's characteristics and the effects for performance of venture business which are in the Daedeok valley. To achieve the purpose of this research, an empirical study by using research model and hypotheses including the general characteristics of venture business and CEO's demographic characteristics has been presented as a research method for relation analysis. The principal findings of the research and its significance are summarized as follows: First, it was found that there is a significant different in the performance of CEO's behavioral characteristics by the scale, type and growing step of organization for venture business. Second, it was found that there is not a significant between an academic career, management experience, foundation experience for business and related working experience of venture CEO and the performance, but there os a partially significant difference in CEO's behavioral characteristics. Third, it was found that there is a partially significant difference between CEO's behavioral characteristics of venture business and the performance by the general characteristics of organization for venture business and demographic characteristics. In conclusion, in spite of the insufficient research for venture business in Daedeok, the implications of theses findings and contributions made by this research is to confirm the characteristics factor of CEO for venture business and general characteristics of organization for venture business by multidisciplinary side. In addition, the findings provide the basis for the analyzing of managerial strong point and weak point referred to supporting system for venture business. Finally, the findings of this study suggest that the results should be a useful data for groping a solution for upbringing plans in terms of a long-term point of view.

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Perspective of breaking stagnation of soybean yield under monsoon climate

  • Shiraiwa, Tatsuhiko
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.8-9
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    • 2017
  • Soybean yield has been low and unstable in Japan and other areas in East Asia, despite long history of cultivation. This is contrasting with consistent increase of yield in North and South America. This presentation tries to describe perspective of breaking stagnation of soybean yield in East Asia, considering the factors of the different yields between regions. Large amount of rainfall with occasional dry-spell in the summer is a nature of monsoon climate and as frequently stated excess water is the factor of low and unstable soybean yield. For example, there exists a great deal of field-to-field variation in yield of 'Tanbaguro' soybean, which is reputed for high market value and thus cultivated intensively and this results in low average yield. According to our field survey, a major portion of yield variation occurs in early growth period. Soybean production on drained paddy fields is also vulnerable to drought stress after flowering. An analysis at the above study site demonstrated a substantial field-to-field variation of canopy transpiration activity in the mid-summer, but the variation of pod-set was not as large as that of early growth. As frequently mentioned by the contest winners of good practice farming, avoidance of excess water problem in the early growth period is of greatest importance. A series of technological development took place in Japan in crop management for stable crop establishment and growth, that includes seed-bed preparation with ridge and/or chisel ploughing, adjustment of seed moisture content, seed treatment with mancozeb+metalaxyl and the water table control system, FOEAS. A unique success is seen in the tidal swamp area in South Sumatra with the Saturated Soil Culture (SSC), which is for managing acidity problem of pyrite soils. In 2016, an average yield of $2.4tha^{-1}$ was recorded for a 450 ha area with SSC (Ghulamahdi 2017, personal communication). This is a sort of raised bed culture and thus the moisture condition is kept markedly stable during growth period. For genetic control, too, many attempts are on-going for better emergence and plant growth after emergence under excess water. There seems to exist two aspects of excess water resistance, one related to phytophthora resistance and the other with better growth under excess water. The improvement for the latter is particularly challenging and genomic approach is expected to be effectively utilized. The crop model simulation would estimate/evaluate the impact of environmental and genetic factors. But comprehensive crop models for soybean are mainly for cultivations on upland fields and crop response to excess water is not fully accounted for. A soybean model for production on drained paddy fields under monsoon climate is demanded to coordinate technological development under changing climate. We recently recognized that the yield potential of recent US cultivars is greater than that of Japanese cultivars and this also may be responsible for different yield trends. Cultivar comparisons proved that higher yields are associated with greater biomass production specifically during early seed filling, in which high and well sustained activity of leaf gas exchange is related. In fact, the leaf stomatal conductance is considered to have been improved during last a couple of decades in the USA through selections for high yield in several crop species. It is suspected that priority to product quality of soybean as food crop, especially large seed size in Japan, did not allow efficient improvement of productivity. We also recently found a substantial variation of yielding performance under an environment of Indonesia among divergent cultivars from tropical and temperate regions through in a part biomass productivity. Gas exchange activity again seems to be involved. Unlike in North America where transpiration adjustment is considered necessary to avoid terminal drought, under the monsoon climate with wet summer plants with higher activity of gas exchange than current level might be advantageous. In order to explore higher or better-adjusted canopy function, the methodological development is demanded for canopy-level evaluation of transpiration activity. The stagnation of soybean yield would be broken through controlling variable water environment and breeding efforts to improve the quality-oriented cultivars for stable and high yield.

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Mammalian Cloning by Nuclear transfer, Stem Cell, and Enzyme Telomerase (핵치환에 의한 cloning, stem cell, 그리고 효소 telomerase)

  • 한창열
    • Korean Journal of Plant Tissue Culture
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    • v.27 no.6
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    • pp.423-428
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    • 2000
  • In 1997 when cloned sheep Dolly and soon after Polly were born, it had become head-line news because in the former the nucleus that gave rise to the lamb came from cells of six-year-old adult sheep and in the latter case a foreign gene was inserted into the donor nucleus to make the cloned sheep produce human protein, factor IX, in e milk. In the last few years, once the realm of science fiction, cloned mammals especially in livestock have become almost commonplace. What the press accounts often fail to convey, however, is that behind every success lie hundreds of failures. Many of the nuclear-transferred egg cells fail to undergo normal cell divisions. Even when an embryo does successfully implant in the womb, pregnancy often ends in miscarriage. A significant fraction of the animals that are born die shortly after birth and some of those that survived have serious developmental abnormalities. Efficiency remains at less than one % out of some hundred attempts to clone an animal. These facts show that something is fundamentally wrong and enormous hurdles must be overcome before cloning becomes practical. Cloning researchers now tent to put aside their effort to create live animals in order to probe the fundamental questions on cell biology including stem cells, the questions of whether the hereditary material in the nucleus of each cell remains intact throughout development, and how transferred nucleus is reprogrammed exactly like the zygotic nucleus. Stem cells are defined as those cells which can divide to produce a daughter cell like themselves (self-renewal) as well as a daughter cell that will give rise to specific differentiated cells (cell-differentiation). Multicellular organisms are formed from a single totipotent stem cell commonly called fertilized egg or zygote. As this cell and its progeny undergo cell divisions the potency of the stem cells in each tissue and organ become gradually restricted in the order of totipotent, pluripotent, and multipotent. The differentiation potential of multipotent stem cells in each tissue has been thought to be limited to cell lineages present in the organ from which they were derived. Recent studies, however, revealed that multipotent stem cells derived from adult tissues have much wider differentiation potential than was previously thought. These cells can differentiate into developmentally unrelated cell types, such as nerve stem cell into blood cells or muscle stem cell into brain cells. Neural stem cells isolated from the adult forebrain were recently shown to be capable of repopulating the hematopoietic system and produce blood cells in irradiated condition. In plants although the term$\boxDr$ stem cell$\boxUl$is not used, some cells in the second layer of tunica at the apical meristem of shoot, some nucellar cells surrounding the embryo sac, and initial cells of adventive buds are considered to be equivalent to the totipotent stem cells of mammals. The telomere ends of linear eukaryotic chromosomes cannot be replicated because the RNA primer at the end of a completed lagging strand cannot be replaced with DNA, causing 5' end gap. A chromosome would be shortened by the length of RNA primer with every cycle of DNA replication and cell division. Essential genes located near the ends of chromosomes would inevitably be deleted by end-shortening, thereby killing the descendants of the original cells. Telomeric DNA has an unusual sequence consisting of up to 1,000 or more tandem repeat of a simple sequence. For example, chromosome of mammal including human has the repeating telomeric sequence of TTAGGG and that of higher plant is TTTAGGG. This non-genic tandem repeat prevents the death of cell despite the continued shortening of chromosome length. In contrast with the somatic cells germ line cells have the mechanism to fill-up the 5' end gap of telomere, thus maintaining the original length of chromosome. Cem line cells exhibit active enzyme telomerase which functions to maintain the stable length of telomere. Some of the cloned animals are reported prematurely getting old. It has to be ascertained whether the multipotent stem cells in the tissues of adult mammals have the original telomeres or shortened telomeres.

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