• Clinical and Experimental Reproductive Medicine
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• v.30 no.4
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• pp.293-298
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• 2003

목 적: 인간의 배아줄기세포는 전분화능과 영속성을 가지고 있어 발생 및 분화에 관련된 기초 연구 뿐 만 아니라 재생의학, 약물검색 등에서도 매우 유용한 재료로 이용될 수 있다.본 연구에서는 유전체의 변형이 배아줄기세포주의 확립 효율에 미치는 영향을 살펴보고자 비정상적인 포배기 배아에서 내세포괴를 분리하여 배양하였다. 연구 방법: 인간의 체외수정 및 배아이식술에서 공여 받은1개 또는3개의 전핵이 관찰되는 비정상 수정란 (n=20)과 착상전 유전진단에서 이수성이 확인된 배아 (n=27)를 대상으로 하였다. 일반적인 immunosurgery 방법으로 영양배엽세포들을 제거하고 내세포괴를 분리한 후 PMEF 혹은 STO feeder 세포위에서 배양하였다. 배아줄기세포의 배양시스템을 검증하기 위해서 이미 확립된 Miz-hES1 cell line을 동시에 같은 조건 하에서 계대배양하였다. 결 과: 비정상 수정란에서 발생된 포배기 배아에서 분리한 1개의 내세포괴가 배아줄기세포와 유사한 colony를 형성하였으나, 계대배양에는 실패하였다. 이수성 배아에서 발생된 포배기 배아의 내세포괴 배양에서는 두개의 colony가 계대배양 중에 영양배엽세포의 형태로 분화되어 미분화 상태를 유지하지 못하였다. 동일한 시기와 조건 하에서 계대배양된 Miz-hES1 cell line이 미분화상태로 유지됨을 karyotyping (46, XY)과 immunophenotyping (positive in SSEA-3 and -4)으로 확인하였다. 결 론: 본 연구의 결과에서 비정상 수정란과 이수성 배아에서 발생된 포배기 배아에서 유래한 내세포괴는 배아줄기세포주 확립 및 미분화 상태 유지 능력이 매우 저조한 것으로 여겨진다. 따라서, 인간의 배아줄기세포주를 확립하는데 있어 배아의 정상여부가 중요한 요소로 작용할 것으로 생각된다.

• Clinical and Experimental Reproductive Medicine
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• v.33 no.1
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• pp.25-33
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• 2006

Objective: The aim of this study was to investigate whether embryonic stem (ES) cells can be established from isolated blastomeres of mouse embryos. Methods: Blastomeres were separated from mouse (C57Bl/6J) 2- or 4-cell embryos. Isolated blastomeres or whole 4-cell embryos were co-cultured with mitosis-arrested STO feeder cells in DMEM supplemented with recombinant murine leukemia inhibitory factor and ES-qualified fetal bovine serum. After the tentative ES cell lines were maintained from isolated blastomeres or whole embryos, some of them were frozen and the others were sub-cultured continually. Characteristics of tentative ES cell lines as were evaluated for specific genes expressions with immunocytochemistry and RT-PCR. Results: One ES cell line (3.0%) was established from isolated blastomere of 2-cell embryo and one cell line (4.0%) from isolated two blastomeres of 4-cell embryo. And five cell lines (16.7%) were established from whole 4-cell embryos. Both cell lines from isolated blastomere and whole embryo expressed mouse ES cell specific markers such as SSEA-1, Oct-4 and alkaline phosphatase. Marker genes of three germ layers were expressed from embryoid bodies of both cell lines. Conclusion: This study suggests that mouse ES cells could be established from isolated blastomeres, although the efficiency is lower than whole embryos. This animal model could be applied to establishment of autologous human ES cells from biopsied blastomeres of preimplantation embryos in human IVF-ET program.

• Horticultural Science & Technology
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• v.34 no.2
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• pp.305-313
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• 2016

Brassica juncea (2n = 4x = 36, AABB genome, 1,068 Mb) is a U's triangle species and an amphidiploid derivative of B. rapa and B. nigra. Fifteen varieties were used to study the ITS (internal transcribed spacer) regions of ribosomal DNA and MITEs (miniature inverted-repeat transposable elements) with a view of developing specific molecular markers. ITSs and MITEs are an excellent resource for developing DNA markers for genomics and evolutionary studies because most of them are stably inherited and present in high copy numbers. The ITS (ITS1 and ITS2) sequence was compared with the consensus sequence of B. rapa and B. nigra. Variation in ITS1 created two separate groups among 15 varieties, with 10 varieties in one group and 5 in the other. Phylogenetic analysis revealed two major clusters for those 10 and 5 varieties. Among the 160 different MITE primers used to evaluate the selected 15 varieties of B. juncea, 70 were related to the Stowaway, 79 to the Tourist, 6 to the hAT, and 5 to the Mutator super-families of MITEs. Of 160 markers examined, 32 were found to be polymorphic when fifteen different varieties of B. juncea were evaluated. The variety 'Blackgat' was different from the other mustard varieties with respect to both phenotype and genotype. The diversity of 47 additional accessions could be verified using eight selected molecular markers derived from MITE family sequences. The polymorphic markers identified in this study can be used for varietal classification, variety protection, and other breeding purposes.

• Journal of Periodontal and Implant Science
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• v.25 no.3
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• pp.587-602
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• 1995

The purpose of this study was to compare the effects of citric acid and tetracycline HCI application to the root surfaces of periodontally diseased teeth on the proliferation and spreading of human periodontal ligament cells. The roots were prepared so that the comparison could be made among root planed, citric acid treated and tetracycline HCI treated surfaces. In the cell proliferation experiment, human periodontal ligament cells at a concentration of $1{\times}10^5$ cells/ml were seeded in each culture well with specimens and incubated for 6 hours. Then, the specimens were transferred to a fresh culture well and incubated for 24, 48, 72 hours respectively. The cell counting was done after trypsinization. In the cell spreading experiment, $1{\times}10^4$ cells/ml were seeded in each culture well and incubated for 30min, 6 hours and 24 hours at 37.5$^{\circ}C$ in a $CO_2$ incubator. Then, all specimens were fixed with phosphate buffered glutaraldehydes, postfixed with phosphate buffered osmium tetraoxide, stained with phosphate buffered tannic acid, dehydrated in ethanol, dried at a critical point, coated with gold and examined under a scanning electron microscope. The results were as follows:In the cell proliferation experiments, the number of attached cells increased more in the tetracycline treated group than in the other groups. In the initial attachment, the appearance of the tetracycline treated the groups was slightly more spread out than in the other groups. After 6 hours of incubation, it was observed in most of the cells that cell morphologic alteration went from ovoid shapes sto spindle shapes. After 24 hours of incubation, the cells of all groups had a fusiform appearance and were connected to each other by numerous cytoplasmic processes. The tetracycline and citric acid treated groups had a similar spreading appearance of periodontal ligament cells, but the tetracycline treated group was more effective in the cell proliferation than the citric acid group.

• Sijohaknonchong
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• v.25
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• pp.75-100
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• 2006

This treatise puts with ecology that important topic is becoming in Multimedia age today. Is appearing to some meaning that symbol that. Is nature friendship and nature assimilation in korean verse and modern novel. And is the purpose to draw diachronic and synthetic thought between age and genre is forming by ecological imagination how. Our korean verse thinks of nature as residing space, and is singing life that is nature friendship and nature assimilation in relation of indivisibility sto of human and nature. And nature space of metaphor or symbol is forming by ecological imagination in the modern novel. Therefore, these two genres see that traffic is available in diachronic synthetic relation. First, must escape resolutely in ideas that literature is basing in actuality and search the literature-ecological imagination. Therefore, forward literature may have to look for the literature-ecological imagination with many interests to green literature ecology and show image that move constantly. And must approach appearing common view of nature and the literature-ecological imagination in principle of integration of expropriation and production now all round to our literary productions. Therefore, must do so that can be nature friendship and become practical education model that expropriation of ecological literary productions and production activity foster literary sensibility and imagination. Also, lively research and groping about each genre of a Korean literature are to premised in diachronic and synthetic veins I will. Method groping that adapt on New Age as defending peculiar special quality that founder is keeping korean verse with opened thinking may have to be spread more hard. Therefore, genre of novel can may ready the one clue to grope confrontation method naturally to secure new identity in new literature environment of digital age.

• Development and Reproduction
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• v.6 no.1
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• pp.55-66
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• 2002

Embryonic stem cells(ES cells) are derived from the inner cell mass(ICM) of blastocysts, which have the potentials to remain undifferentiated, to proliferate indefinitely in vitro, to differentiate into the derivates of three embryonic germ layers. ES cells are an attractive model system for studying the initial developmental decisions and their molecular mechanisms during embryogenesis. Additionally, ES cells of significant interest to those characterizing the various gene functions utilizing transgenic and gene targeting techniques. We investigated the effects of reproductive hormones, gonadotropins(GTH) and steroids on the induction of differentiation and expressions of their receptor genes using the newly established mouse ES cells. We collected the matured blastocysts of inbred mice C57BL/6J after superovulation and co-cultured with mitotically inactivated STO feeder cells. After 5 passages, we confirmed the expression alkaline phosphatase(Alk P) activity and SSEA-1, 3, 4 expressions. The protocol devised for inducing ES differentiation consisted of an aggregation steps, after 5 days as EBs in hormone treatments(FSH, LH, E$_2$, P$_4$, T) that allows complex signaling to occur between the cells and a dissociation step, induced differentiation through attachment culture during 7 days in hormone treatments. Hormone receptors were not increased in dose-dependent manner. All hormone receptors in ES cells treated reproductive hormones were expressed lower than those of undifferentiated ES cell except for LHR expression in E$_2$-treated ES cells group. After hormone induced differentiation, at least some of the cells are not terminally differentiated, as is evident from the expression of Oct-4, a marker of undifferentiated. To assess their differentiation by gene expression, we analyzed the expression of 7 tissue-specific markers from all three germ layers. Most of hormone-treated group increased in the expression of gata-4 and $\alpha$ -fetoprotein, suggesting reproductive hormone allowed or induced differentiation of endoderm.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.4
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• pp.280-288
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• 1990

Quality stability of dried lavers during roasting and storage was investigated by measuring the changes of pigment contents including chlorophyll a, carotenoids and biliproteins, the content of trypsin indigestible substrates(TIS), in vitro apparent protein digestibility, and dietary fiber. In heat treatment or roasting of dried laver, carotenoids and chlorophyll a were found to be more stable than biliproteins. Chlorophyll a and carotenoids were retained more than $85\%$ during roasting for 1 hour at $120^{\circ}C$ while biliproteins were retained only $10\%$ at the same temperature. The in vitro digestility of dried layers tended to increase with raising the roasting temperature. The in vitro digestibility of $85\%$ for the roasted laver at $100^{\circ}C$ was higher than that observed in the control of $80\%$. There was a correlation between the decrease in TIS and biliproteins as the laver was roasted. The soulble dietary fiber(SDF) content was substantially increased by heat treatment. The extent of protein digestiblility appeared to be related to the increase of SDF content. In the storage of roasted lavers under both water activities 0.1 and 0.65, the loss of the pigments and TlS were markedly retarded at Aw 0.1. Chlorophyll a was retained about $20\%$ at aw 0.65 and $75\%$ at aw 0.1 after 20 week sto-rage. At worst, more than $90\%$ of the carotenoids were lost at aw 0.65 after 20 week, while biliproteins were comparatively stable at the same water activity. TIS decreased about $15\%$ and in vitro apparent protein digestibility increased up to $92\%$ at aw 0.65 during storage.

• Cartoon and Animation Studies
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• s.9
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• pp.127-142
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• 2005

Not only in Korea but throughout the entire world millions of people are in contact with images. Images have become a medium through which to transmit anything from simple visualizations of moving images to knowledge and information. The age of the internet has arisen thanks to scientific development, and the internet generation's acquisition of information is continuously becoming faster. The spectators, ufo must choose amongst the excessive amount of available information, are changing along with it just as quickly. The method of visual transmission has changed to match the demands of the fast-changing pace of the new generation. In order to receive an instantaneous selection amongst much information, the primary requisite is attracting one's attention, and then presenting a corresponding feeling of satisfaction. The early stages of film arose from the desire to capture one's actual situation as it realty is. Unsatisfied with the still picture, people developed the motion picture. Research has succeeded in reproducing 3-dimensional images more realistic than the actual image we perceive as a result of the difference in visual perspective of both eyes and their response to rays of light From color film to 3-dimensional pictures, people enjoy the magnificent results of this. All fields within the category of film are continuously studying the human desire to pursue their visual side, namely the pursuit of visual images with a maximum sense of reality. The images that millions of people around the world see now are flat. The screen's depth and optical illusions effectively give a sense of reality while conveying information. However, although the flat screen is able to create a sense of depth using the different visual perspective of each eye for the realization of a cubic effect, there are limitations. Entering the 21s1 century, there is a quickly-arising branch within the field of image media which seeks to overcome these limitations Although 3-dimensional images began in films, entering the latter half of the 20th century, due to development of 3-dimensional images using the mediums of the animation field, cellular phones, advertisement screens, television etc., without restriction is designated as 'image.'. With research having started around 1900 and continuing for over 100 years, we are now able to witness the popularization of 3-dimensional films happening before our very eyes. Within our own country, we can frequently see them at amusement parks and museums. In the future, through the popularization of HDTV etc., there is a good outlook for practical use of 3-dimensional images in televisions with advanced picture qualify as well as in other areas. Together with the international current, research on 3-dimensional films has been activated in Korea and is rising as a main current in the film industry. Within this context, the contents and understanding of 3-dimensional images must keep in step with the pace of technical advancements. In order to accelerate of development of film contents to keep in pace with technical developments, this dissertation presents the techniques and technical aspects of future developments, and shows the need to prepare in advance to make the field grow- and thereby avoid having a lack of experts and being conquered by other nations in the field - rather than only advancing the technical aspects and importing the contents. This dissertation aims to stimulate interest and continual research by progressive-thinking people related to the film industry. Part II looks into the definition and types of 3-dimensional motion pictures, the terminology, the fundamentals of image formation, current market fluctuations, and looks into 3-dimensional techniques which can be borrowed and introduced in 3-dimensional animations. Part III concerns 3-dimensional animated films. It analyzes 3-dimensional production techniques while using the introduction of specific animation techniques in the 2004 production Lee Sun Shin and Nelson - Naval Heroes 3-dimensional animation produced in 2004 by Clay & Puppet Stop-Motion Animation & Computer Graphic. Original Korean title: 해전영웅 이순신과 넬슨. as an example, and it also looks into how current film techniques used in animations can be applied in 3-dimensional films. Additionally, the actual stages of the various fields of 3-dimensional animations are presented. Given the current direction and advancement of 3-dimensional films making use of animations and the possible realization of this field, the author plans to weigh the development of this yet unexploited new market Not looking at the current progress of the field, but rather the direction of the hypothetical types of animation techniques, the author predicts the marketability and possibility of development of each area.

• Journal of architectural history
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• v.14 no.1 s.41
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• pp.89-105
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• 2005

The central aim of this thesis is to see if the structure of Palsangjeon(捌相殿) in Pubjoo Temple(法住寺), a five sto wooden pagoda in Chosen(朝鮮) Dynasty, was handed down from the ancient and middle ages. This study was performed through an analysis of Gilt-Bronze Pagoda built in Koryo(高麗) period. In other words, it is aimed at analyzing which lineage the structure of Palsangjeonbelongs to as a wooden pagoda. In analyzing the structure of Palsangjeon, I attempted to find out its source from the remains of Koryo period prior to the Chosen Dynasty. Examples are the Gilt-Bronze Pagoda, built during the Koryo period. I have also examined its relationship with other existing wooden pagodas and remains. The analysis of Palsangjeon, a five story wooden pagoda in Chosen Dynasty, focuses on the following: First, I explored the possibilities of whether the structure of Palsangjeon was newly invented in Chosen Dynasty, or if it had been derived from the wooden pagodas in the Koryo period. Secondly, I tried to find out if the stable vertical planes, with a great successive diminution ratio, were derived from the middle age, i.e. Koryo period. The results of the study of Palsangjeon through Gilt-Bronze Pagoda analysis are as follows: 1. The structure of Gilt-Bronze Pagoda, a wooden pagoda from the Koryo period, is roughly classified into the accumulation type, using pipe pillars, and the one story type using whole pillars. In the accumulation type, stories are connected in either a flat format or an intervening format. The Gilt-Bronze Pagoda is mainly composed of pipe pillars, with some whole pillars. However, the central pillar was omitted in the building structure. Generally, the upper and lower stories are connected by pipe pillars in a crutch format. All the pillars, whether they are pipe pillars or whole pillars, used Naiten(內轉) technology. The Eave supporter has the Haang type(下昻) and the Muhaang type(無下昻). In most cases, high balustrades are furnished, but few tables of high balustrades have been found. The slanting roof formats have been handed down from Paekche(百濟), Silla(新羅), or Koryo(高麗). However, the structure of the octagon is assumed to be derived from Koguryo(高句麗). The structure of the Gilt-Bronze Pagoda from the Koryo period is mainly composed of accumulated flat squares, with some spire types. intervening format, the structure of Palsangjeon used whole pillars in a half story format in which upper level side pillars are installed on the lower level tie beam. From the Bronze Pagoda from the Koryo period, we can assume that the half story format of wooden pagodas that has stable vertical planes with a great successive diminution ratio was created during the mid-Koryo period at the latest and had been idly developed by the time of the Chosen Dynasty. 3. The whole pillars in Palsangjeon are also found in Gilt-Bronze Pagodas from the Koryo period. Hence, all of the pillars in Palsangjeon seem to have been handed down from the ancient construction technology. They were also used in the construction of wooden pagodas from the Koryo period. Therefore, it is assumed that Palsangjeon was constructed using the construction technology of the Chosen Dynasty that had been developed from the wooden pagoda construction technology of the Koryo period. The stable vertical planes with a great successive diminution ratio in Palsangjeon are derived from ancient Korean wooden pagodas, which have developed into indigenous Korean wooden pagodas with fairly stable vertical planes and a great design, in the half story format of Koryo and Chosen Dynasty. Therefore, it is assumed that the structure of Palsangjeon has a systematic relationship with traditional Korean wooden pagodas and is one of the indigenous Korean wooden pagoda structures. 4. In China, the intervening format has been mainly used between stories in multi-story architecture since the ancient days. At the same time, the flat format as also used in ancient and middle ages. However, the flat format was replaced by whole pillars during the Ming(明) and Manchu(淸) Dynasties, in favor of simple and compact construction. The half-story format, in which upper level side pillars are installed on tie beams, has been found in some cases, but it doesn't seem to have been the primary construction technology. Few traces of the half-story format have been found in multi-story architecture in Japan, and it has not been used as a general construction format. By contrast, the half-story format, which seems to have been derived from the Koryo period, was used as a general construction format in multi-story architecture of the Chosen Dynasty. The construction technology of multi-story architecture is related to that of multi-story wooden pagodas, but they have different production technologies. It seems that the structure of Palsangjeon did not just adopt the construction technology of multi-story architecture in the Chosen Dynasty, but it was developed from wooden pagodas in the Koryo period, including the Gilt-Bronze Pagoda. 5. Since the ancient days, most Chinese and Japanese wooden pagodas have adopted an accumulation type of structure using pipe pillars, with accumulated pointed towers. On the other hand, though most Korean wooden pagodas have also adopted an accumulation type of structure from the ancientdays, one story type using whole pillars was created in the Koryo and Chosen Dynasties. The wooden pagoda structure of Palsangjeon, with stable vertical planes in a half story format, is a unique Korean construction technology, different from the construction technologies of Chinese and Japanese wooden pagodas. This thesis clearly determined the structural characteristics of Palsangjeon. However, various remains have yet to be analyzed in depth, to establish an accurate construction technology system. In the beginning of this thesis, I had difficulty in precisely interpreting the internal structure of the Gilt-Bronze Pagoda from its appearance. However, in the process of study, the more serious problem was that there are few remains or ruins of multi-story architecture in ancient and the middle ages of Korea. Therefore, it is urgent to discover various remains in the future. This thesis succeeded in determining the structural characteristics of Palsangjeon. However, it fell short of clarifying the structural lineage of the stable vertical planes, although they show indigenous Korean architectural taste, representing the unique national emotion, and the construction format of multi-story wooden pagodas in Korea. I hope this is clarified in the future research.

• The Journal of Natural Sciences
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• v.1
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• pp.61-113
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• 1987

The increasing emphasis placed on the production of fine turf for lawns, golf courses, parks, and other recreational sites has led to many unsolved problems as to how such turf could be best established and mainteined. For this purpose, a series of experiments were conducted under con ditions of pot and field. The results obtained were as follows EXPERIMENT I. The effect of nitrogen fertilizer and clipping interval on Zoysia japonica. 1. Increasing the rate of nitrogen and frequent clipping increased tiller number of Zoysis japonica and the maximum number of tillers were obtained from 700 kg N application and freqnent clippings (10 days interval ) in October. Treatment of 350kg N with 10 days clipping interval increased tillers much more than those of 700 kgN with 20 and 30 days clipping intervals. 2. The average number of green leaves occurred during the growth period maximized by applying 700 kg N and clipping 10 days interval. 3. Increasing tiller numbers significantly decreased tops DM weight per tiller by clipping plants at interval of 10 and 20 days, irrespective of nitrogen applied, and with nil N, at the interval of 30 days. By applying 700 kg N, however, top DM weight per tiller increased as the number of tillers increased consistently. 4. The highest top DM weight was achieved from late August to early September by applying 350 and 700kgN. 5. During the growth period, differences in unders ( stolon + root ) DM weight occurred bynitrogen application were found between nil N and two applied nitrogen levels, whereas, at the same level of nitrogen applied, the increase in stolon DM weight enhanced by lengthening the clipping interval to 30 days. 6. Nitrogen efficiency to green leaves, stolon nodes and DM weight of root with high nitrogen was achieved as clipping interval was shortened. 7. By increasing fertilizer nitrogen rate applied, N content n the leaves and stems of Zoysiajaponica was increased. On the other hand, N content in root and stolon had little effect onfertilizer nitrogen, resulting in the lowest content among plant fractions. The largest content of N was recorded in leaves. Lengthening the clipping interval from 10 or 20 to 30 days tends to decrease the N content in the leaves and stems, whereas this trend did not appeared in stolon androot. 8. A positive correlations between N and K contents in tops and stolon were established andthus K content increased as N content in tops and stolon increased. Meanwhile, P content was not affected by N and clipping treatments. 9. Total soluble carbohydrate content in Zoysia japonica was largest in stolon and stem, and was reduced by increasing fertilizer nitrogen rate. Reduction in total soluble carbohydrate due to increased nitrogen rate was severer in the stolons and stems than in the leaves. 10. Increasing the rate of nitrogen applied increased the number of small and large vascular bundles in leaf blade, but shortened distance among the large vascular bundles. Shortening the clipping interval resulted in increase of the number of large vascular bundles but decrease ofdistance between large vascular bundles.EXPERIMENT II. Growth response of Zoysia japonica imposed by different plant densities. 1. Tiller numbers per unit area increased as plant density heightened. Differences in num ber between densities at higher densities than 120 D were of no significance. 2. Tiller numbers per clone attained by 110 days after transplanting were 126 at 40D,77 at 80D, 67 at 120D, 54 at 160D, and 41 at 200D. A decreasing trend of tiller numbers per clone with increasing density was noticable from 100 days after transplanting onwards. 3. During the growth period, the greatest number of green leaves per unit area were attainedin 90days after transplanting at 160D and 200D, and 100 days after transplanting at 40D, 80Dand 120D. Thus the period to reach the maximum green leaf number with the high plantdensity was likely to be earlier that with the low plant density. 4. Stolon growth up to 80 days after transplaning was relatively slow, but from 80 daysonwards, the growth quickened to range from 1.9 m/clone at 40D to 0.6m/clone at 200Din 200 days after transplanting, these followed by the stolon node produced. 5. Plant density did not affect stolon weight/clone and root weight/clone until 80 daysafter transplanting. 6. DM weight of root was heavier in the early period of growth than that of stolon, butthis trend was reversed in the late period of growth : DM weight of stolon was much higherthan that of root.EXPERIMENT Ill. Vegetative growth of Zoysia japonica and Zoysia matrella as affected by nitrogen and clipping height. 1. When no nitrogen was applied to Zoysia japonica, leaf blade which appeared during theAugust-early September period remained green for a perid of about 10 weeks and even leavesemerged in rate September lived for 42 days. However, leaf longevity did not exceed 8 weeks asnitrogen was applied. In contrast the leaf longevity of Zoysia matrella which emerged during the mid August-earlySeptember period was 11 weeks and, under the nitrogen applied, 9 weeks, indicating that thelife-spen of individual leaf of Zoysia matrella may be longer than that of Zoysia japorica. Clipping height had no effect on the leaf longevity in both grasses. 2. During the July-August period, tiller number, green leaf number and DM weightof Zoysia japonica were increased significantly with fertilizer nitrogen, but were not with twolevel of clipping height. This trend was reversed after late September ; no effect of nitrogen wasappeared. Instead, lax clipping increased tiller number, green leaf number and DM weight. Greenleaves stimulated by lax clipping resulted in the occurrance of more dead leaves in late October. 3. Among the stolons outgrown until early September, the primary stolon was not influencedby nitrogen and clipping treatments to produce only 2-3 stolons. However, 1st branch stoIon asaffected by nitrogen increased significantly, so most of stolons which occurred consisted of 1st branch stolons. 4. Until early September, stolon length obtained at nil nitrogen level was chiefly caused bythe primary stolons. By applying nitrogen, the primary stolons of Zoysia japonica waslonger than 1st branch stolons when severe clipping was involved and in turn, shorter than 1stbranch stolons when lax clipping was concerned. In Zoysia matrella, 1st branch stolons were muchlonger than the primary stolon when turf was clipped severely but in conditions of lax clippingthere was little difference in length between primary and 1st branch stolons. 5. Stolon nodes of both Zoysia japonica and Z. matrella were positively influenced by nit rogen, but no particular increase by imposing clipping height treatment was marked in Zoysiamatrella. Although the stolon of Zoysia japonica grew until late October, the growthstimulated by nitrogen was not so remarkable as to exceed that by nil N.