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Effect of Er:YAG lasing on the dentin bonding strength of two-step adhesives (2단계 접착제의 상아질 결합강도에 대한 Er:YAG 레이저 조사 영향)

  • Song, Byeong-Choon;Cho, Young-Gon;Lee, Myung-Seon
    • Restorative Dentistry and Endodontics
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    • v.36 no.5
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    • pp.409-418
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    • 2011
  • Objectives: The purpose of this study was to compare the microshear bond strength (${\mu}$SBS) and bonding interfaces of two-step total-etching and self-etching adhesive systems to three etch types of dentin either the acid etched, laser etched or laser and acid etched. Materials and Methods: The occlusal dentinal surfaces of thirty human molars were used. They were divided into six groups: group 1, 37% $H_3PO_4$ + Single Bond 2 (3M ESPE); group 2, Er:YAG laser (KEY Laser 3, KaVo) + Single Bond 2; group 3, Er:YAG laser + 37% $H_3PO_4$ + Single Bond 2; group 4, Clearfil SE Primer + Bond (Kuraray); group 5, Er:YAG laser + Clearfil SE Bond; group 6, Er:YAG laser + Clearfil SE Primer + Bond. The samples were subjected to ${\mu}$SBS testing 24 hr after bonding. Also scanning microscopic evaluations were made on the resin-dentin interfaces of six specimens. Results: The ${\mu}$SBS of group 2 was significantly lower than that of groups 1 and 3 in Single Bond 2 (p < 0.05). There were significant differences among the uSBS of groups 4, 5, and 6 in Clearfil SE Bond (p < 0.05). Very short and slender resin tags were observed in groups 2 and 5. Long and slender resin tags and lateral branches of tags were observed in groups 3 and 6. Conclusions: Treatment of dentin surface using phosphoric acid or self-etching primer improved the adhesion of Er:YAG lased dentin.

Studies on the Quality of Korean Rice (한국쌀의 품질에 관한 연구)

  • Kim, Z.U.;Lee, K.H.;Kim, D.Y.
    • Applied Biological Chemistry
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    • v.15 no.1
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    • pp.65-75
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    • 1972
  • The rice qualities including cooking and eating qualities were studied using recommended Korean rice varieties (20 of japonica and 3 of indies type; IR 667) which were grown at Suwon, Korea in 1971. As the result, followings were obtained. 1. Amylose contents of white rice were varied with the varieties 21.1 to 25.5% and the average was 23.0%. Three indica type varieties (IR 667) showed higher amylose contents than the other japonica type varieties except Mankyung. Among japonica type varieties, Palkum, Mankyung composed the group of the highest amyloes content and Kimmaje was the lowest. 2. Blue values were distributed in the range of 0.38 to 0.48 and the average was 0.42 IR 667 varieties showed the highest blue value among them. Among japonica type varieties, Jaegun showd the highest blue value and Sooseung, Shirogane showed successively lower values, Shin #2, Nongbaik, Palkweng, Suwon #82, Mankyung, Nonglim #25 and Nongkwang relatively lower blue values. 3. Alkali numbers were in the range of 6.0 to 7.4 and the average was 6.8. Much difference was not shown in alkali number between IR 667 group and the japonica varieties group. 4. Gelatinization temperature were ranged from 59.5 to 64.0 IR 667 varieties showed relatively higher gelatinization temperature than japonica type varieties. 5. Water uptake ratios were measured in the range of 2.67 to 2.92 and the average was 2.79. IR 667 varieties were belonged to the group of highest water uptake ratio. Among japonica type varieties Kimmaje, Suwon #82, Nonglim #29, Deungpan #5, Jaegun, Jinhung, were belonged to the group of relatively high water uptake ratio and Palkweng, Palkeum and Paldal to the relatively low water uptake ratio. 6. Expaned volums were ranged from 29.8 to 33.7 and the average was 31.8. IR 667 varieties showed higher expanded volumes than japonica type varieties. 7. Intensities of starch-iodine blue value of residual liquid indicated 0.35 to 0.58. Among them IR 667 varieties showed relatively high intensities. 8. The range of total solids in residual liquids was 0.605 to 0.810 and the average was 0.700 Much difference was not shown in total solids in residual liquid between IR 667 varieties and japonica varieties. 9. pH values of residual liquids were in the range of 6.3 to 7.3 and the average was 6.95. IR 667 varieties showed lower pH than japonira type varieties.

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Enzymatic Method for Measuring ATP Related Compounds in Fish Sauces (효소법에 의한 액젓중의 ATP 관련물질 측정)

  • CHO Young Je;IM Yeong Sun;KIM Sang Moo;CHOI Young Joon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.4
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    • pp.385-390
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    • 1999
  • HPLC method usually has been used for the determination of ATP and its related compounds in fish muscle and fish sauce. But, total amount of ATP related compounds in fish sauce is determined less than that of fish muscle. In order to establish the extract analysis method for ATP related compounds in fish sauce, a new enzymatic method was developed and compared with existing HPLC method. Fish sauce was extracted with chilled perchloric acid and neutralized to Ph 7.0 with potassium hydroxide solution, the extract was used as sample analyzed by HPLC as usual. On the other hand, for sample analyzed by enzymatic method, 1 ml extract solution was pipetted into test tube. To the tube, 0.5ml of mixed suspension adenosinedeaminase (4U), nucleosidephosphorylase (0.02U) and xanthineoxidase (0.03U) suspended in 2.0ml of 1/15 M sodium phosphate buffer solution pH 7.6 and 1.5ml deionized water wereadded for the decomposition of IMP, HxR and Hx to uric acid at $37^{\circ}C$ for 40 minutes. Total uric acid was determined by measuring optical density at 290nm. In HPLC method, salt decreased the total amount of ATP related compounds by $13.6\~16.2\%$ at $2.5\%$ concentration, but no effect in enzymatic method. IMP, HxR and Hx were detected at 254nm, while uric acid at only 290nm. The ratio of the total amount of ATP related compounds by HPLC method was about $45\%$ of that by enzymatic method in fish sauce. Form these results, enzymatic method is more accurate and simple than HPLC method for analysis of ATP related compounds in fish sauce.

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Development of High Intensity Focused Ultrasound (HIFU) Mediated AuNP-liposomal Nanomedicine and Evaluation with PET Imaging

  • Ji Yoon Kim;Un Chul Shin;Ji Yong Park;Ran Ji Yoo;Soeku Bae;Tae Hyeon Choi;Kyuwan Kim;Young Chan Ann;Jin Sil Kim;Yu Jin Shin;Hokyu Lee;Yong Jin Lee;Kyo Chul Lee;Suhng Wook Kim;Yun-Sang Lee
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.9 no.1
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    • pp.9-16
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    • 2023
  • Liposomes as drug delivery system have proved useful carrier for various disease, including cancer. In addition, perfluorocarbon cored microbubbles are utilized in conjunction with high-intensity focused-ultrasound (HIFU) to enable simultaneous diagnosis and treatment. However, microbubbles generally exhibit lower drug loading efficiency, so the need for the development of a novel liposome-based drug delivery material that can efficiently load and deliver drugs to targeted areas via HIFU. This study aims to develop a liposome-based drug delivery material by introducing a substance that can burst liposomes using ultrasound energy and confirm the ability to target tumors using PET imaging. Liposomes (Lipo-DOX, Lipo-DOX-Au, Lipo-DOX-Au-RGD) were synthesized with gold nanoparticles using an avidin-biotin bond, and doxorubicin was mounted inside by pH gradient method. The size distribution was measured by DLS, and encapsulation efficiency of doxorubicin was analyzed by UV-vis spectrometer. The target specificity and cytotoxicity of liposomes were assessed in vitro by glioblastoma U87mg cells to HIFU treatment and analyzed using CCK-8 assay, and fluorescence microscopy at 6-hour intervals for up to 24 hours. For the in vivo study, U87mg model mouse were injected intravenously with 1.48 MBq of 64Cu-labeled Lipo-DOX-Au and Lipo-DOX-Au-RGD, and PET images were taken at 0, 2, 4, 8, and 24 hours. As a result, the size of liposomes was 108.3 ± 5.0 nm at Lipo-DOX-Au and 94.1 ± 12.2 nm at Lipo-DOX-Au-RGD, and it was observed that doxorubicin was mounted inside the liposome up to 52%. After 6 hours of HIFU treatment, the viability of U87mg cells treated with Lipo-DOX-Au decreased by around 20% compared to Lipo-DOX, and Lipo-DOX-Au-RGD had a higher uptake rate than Lipo-DOX. In vivo study using PET images, it was confirmed that 64Cu-Lipo-DOX-Au-RGD was taken up into the tumor immediately after injection and maintained for up to 4 hours. In this study, drugs released from liposomes-gold nanoparticles via ultrasound and RGD targeting were confirmed by non-invasive imaging. In cell-level experiments, HIFU treatment of gold nanoparticle-coupled liposomes significantly decreased tumor survival, while RGD-liposomes exhibited high tumor targeting and rapid release in vivo imaging. It is expected that the combination of these models with ultrasound is served as an effective drug delivery material with therapeutic outcomes.

Weed Flora of Ulreung Island in Korea (울릉도(鬱陵島)에 발생(發生)하는 잡초종(雜草種))

  • Kim, K.U.;Kwon, S.T.;Lee, I.J.;Kim, S.H.
    • Korean Journal of Weed Science
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    • v.7 no.3
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    • pp.265-279
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    • 1987
  • About 140 weed species belonging to 42 families occurring in summer were observed in Ulreung island. The Compositae was the most wildely occurring family covering 27 weed species, followed by 21 species in Graminae, 9 in Polygonaceae, 7 in Leguminosae, and 7 in Labiatae etc. In terms of the lands classified, about 60 species in 26 families were observed in the cultivated and the medical crops grown areas, respectively, and 116 species in 40 families occurred in the non-cultivated land like the vicinity of the cultivated area and 94 species in 34 families in the valley. No. of species and families were much greater in the non-cutivated land than those of the cultivated one. The most dominant weed species in both the cultivated and its vicinity in Ulreung island were Digitaria sanguinalis, followed by Portulaca oleracea, Polygonum hydropiper, Equisetum arvensis, Artemisia princeps, Commetina communis, Setaria viridis in order. Community analysis was done by the method of Toyohara in two cultivated lands such as the general crop land and the medical herb crop grown land, and two non-cultivated areas such as the vicinity of the cultivated land and valley. The cultivated land consisted of the communites of P. hydropiper and Cyperus amuricus, including Bidens tripartita in P. hydropiper community. The medical crop grown land composed of three major communities like P. hydropiper, Amaranthus mangostanus and Sonchus asper in which A. mangostanus and S. media were presented in the ecoton, indicating community being transiting. In the non-cultivated areas like the vicinity of crop land, the communities of Erigeron annuus, P. oleracea, and Oxalis corniculata were dominant, and Dystaenia takeshimana was included in the community of E. annuus and Stellan'a aquatica in P. oleracea community. In the valley, Ranunculus quelpaertensis community was existed in between the communities of Sonchus asper and Plantago asiatica.

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Chemical Properties on the Quality of Marketed Roasting Green teas (시판 덖음녹차의 품질에 따른 이화학적 특성)

  • 신미경;장미경;서은숙
    • Korean journal of food and cookery science
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    • v.11 no.4
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    • pp.356-361
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    • 1995
  • This study was conducted to know the quality of marketed green teas which were devided into high, middle and low grade according to the price. we examined the content of water, ash, total nitrogen, tannin, caffeine, chlorophyll and color value and did sensory evaluation. The results were as follows: 1) The content of water was 2.17-3.67% and content of ash was 4.50-5.17%, there were no significant difference in each grade. 2) The content of total nitrogen was 4.38% in high grade, 4.60% in middle grade and 4.68% in low grade. 3) The content of tannin was 11.09% in high grade, 14.22% in middle grade and 14.44% in low grade, middle and low grade were significantly higher than high grade. 4) The nitrogen rate to tannin (N/T) was 39.5% in high grade, 32.6% in middle grade and 32.70% in low grade, N/T rate of high grade was significantly highest than others. 5) The content of caffeine is 1.78% in high grade, 1.32% in middle grade and 0.92% in low grade, high and middle grade were significantly higher than low grade. 6) The content of total chlorophyll is 297.37 mg% in high grade, 192.89 mg% in middle grade and 204.79 mg% in low grade, chlorophyll a was 69.23 mg% in high grade, 51.99 mg% in middle grade and 63.42 mg% in low grade, and chlorophyll b was 228.47 mg% in high grade, 131.21 mg% in middle grade and 141.63 mg% in low grade. 7) Yellow value of high and middle grade were significantly higher than low grade, but blue and red value were no significant diffrence in groups. 8) In sensory evaluation, appearance, taste, odor of high grade were better than others and total score was 15.25 in high grade, 12.97 in middle grade and 9.80 in low grade. 9) Price had a positive correlation with caffeine, appearance and taste, but a negative correlation with tannine. NT rate had a negative correlation with tannine, but a positive correlation with caffeine.

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Anti-oxidative Activities of Commercial Edible Plant Extracts Distributed in Korea (국내 유통 중인 식용식물 추출물의 항산화효과)

  • Kim, Kyung-Bum;Yoo, Ki-Hwan;Park, Ha-Yan;Jeong, Jong-Moon
    • Applied Biological Chemistry
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    • v.49 no.4
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    • pp.328-333
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    • 2006
  • Many plant extracts are known to have antioxidative effects. However, their activities can be reduced or disappeared during mass production process. The purpose of this study is to compare antioxidative effects of edible plant extracts distributed in Korea. forty three kinds of edible plant extracts commercially available in Korea were selected and investigated for their total phenolics contents and antioxidative potentials(DPPH radical and superoxide anion radical scavenging activities). In contents of total phenolics, the commercial plant extracts from Artemisia annua(whole plant), Ilex paraguariensis(leaf, Silybum marianum(fruit and leaf, Ulmus pumila(bark), Coliolus versicolor(fruit), and Curcuma longa(root and stem) contained over 70 mg/g of powder, DPPH radical scavenging activities($SC_{50}$, 50% scavenging concentration) of A. annua, I. paraguariensis, Pinus densiflora(leaf),S. marianum, U. pumila, and C. longa were $53.96{\pm}0.81\;ppm,\;24.61{\pm}2.12\;ppm,\;35.96{\pm}1.11\;ppm,\;57.46{\pm}2.13\;ppm,\;55.25{\pm}1.65\;ppm\;and\;12.99{\pm}1.67ppm$, respectively, while that of positive control(vitamin C) was $3.86{\pm}0.81\;ppm$. $SC_{50}$ values against superoxide anion radical of A. annua, Cinnamomum zeylanicum(bark), I. paraguariensis, Rubus coreanus(fruit and leaf), Morus alba(leaf), P. densiflora, S. marianum, U. pumila, C. versicolor, C. longa, Perilla frutescens var. acuta(leaf), and H. sabdariffa(leaf and newer) were $53.21{\pm}1.83ppm,\;50.12{\pm}2.12ppm,\;5.59{\pm}0.84ppm,\;41.60{\pm}8.93ppm,\;20.19{\pm}0.97ppm,\;15.19{\pm}1.66ppm,\;21.20{\pm}1.88ppm,\;15.71{\pm}0.91ppm,\;55.48{\pm}2.42ppm,\;52.12{\pm}2.44ppm,\;23.80{\pm}1.98ppm\;and\;11.14{\pm}0.51ppm$, respectively($SC_{50}$ value of vitamin C: $9.61{\pm}0.93ppm$). In particular, both 1 paraguariensis and P. densiflora had high content of phenolics as well as high scavenging activities of DPPH radical and superoxide anion radical. Consequently, above two commercial extracts may be useful as a source of antioxidative nutraceutics.

Effect of Epigallocatechin Gallate on Phosphoinositide 3-kinase/Akt and Glycogen Synthase Kinase-3 Pathway in Oxidative-stressed N18D3 Cells Following $H_2O_2$ Exposure (산화성 손상을 받은 N18D3세포에서 Epigallocatechin gallate가 Phosphoinositide 3-kinase/Akt 및 Glycogen synthase kinase-3경로에 미치는 효과)

  • Koh, Seong Ho;Kwon, Hyug Sung;Oh, Hwa Soon;Oh, Jae Ho;Park, Ynun Joo;Kim, Jun Gyou;Kim, Ki Sok;Kim, Yang Soon;Yang, Ki Hwa;Kim, Seung U.;Kim, Seung H.;Jung, Hai Kwu
    • Korean Journal of Clinical Pharmacy
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    • v.13 no.1
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    • pp.29-39
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    • 2003
  • Neurodegenerative disorders are associated with apoptosis as a causing factor or an inducer. On the other hand, it has been reported that epigallocatechin gallate (EUG), one of antioxidants and flavonoids, and z-VAD-fmk, a nonselective caspase inhibitor, suppress oxidative-radical-stress-induced apoptosis. However, it is not yet known what is the effects of EGCG and z-VAD-fmk on the apoptotic pathway is through phosphoinositide 3-kinase (PI3K), Akt and glycogen synthase kinase-3 (GSK-3) as well as mitochondria, caspase-3 and poly (ADP-ribose) polymerase (PARP). We investigated the effects of EGCG by using $H_2O_2$ treated N18D3 cells, mouse DRG hybrid neurons. Methods: Following 30 min $100\;{\mu}m\;H_2O_2$ exposure, the viability of N18D3 cells (not pretreated vs. EGCG or z-VAD-fmk pretreated) was evaluated by using MTT assay. The effect of EGCG on immunoreactivity (IR) of cytochrome c, caspase-3, PARP, PI3K/Akt and GSK-3 was examined by using Western blot, and was compared with that of z-Y4D-fmk. Results: EGCG or z-VAD-fmk pretreated N18D3 cells showed increased viability. Dose-dependent inhibition of caspase-3 activation accompanied by PARP cleavage were demonstrated by pretreatment of both agents. However, inhibition of cytochrome c release was only detected in EGCG pretreated N18D3 cells. On the pathway through PI3K/Akt and GSK-3, however, the result of Western blot in EGCG pretreated N18D3 cells showed decreased IR of Akt and GSK-3 and increased IR of p85a PI3K, phosphorylated Akt and GSK-3, and contrasted with that in z-VAD-fmk pretreated N18D3 cells showing no changes on each molecule. Conclusion: These data show that EGCG affects apoptotic pathway through upstream signal including PI3K/Akt and GSK-3 pathway as well as downstream signal including cytochrome c and caspase-3 pathway. Therefore, these results suggest that EGCG mediated activation of PI3K/Akt and inhibition GSK-B could be new potential therapeutic strategy for neurodegenerative diseases associated with oxidative injury.

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Index Cases in Pediatric Surgery - a National Survey by the Korean Association of Pediatric Surgeons, 2000 - (소아외과의 지수 질환 - 대한소아외과학회 정회원을 대상으로 한 2000년도 전국 조사 -)

  • Lee, M.D.;Kim, S.Y.;Kim, W.K.;Kim, I.K.;Kim, S.C.;Kim, S.K.;Kim, J.E.;Kim, J.C.;Kim, H.H.;Park, K.W.;Park, W.H.;Seo, J.M.;Song, Y.T.;Oh, S.M.;Yoo, S.Y.;Lee, D.S.;Lee, S.K.;Lee, S.C.;Chung, S.Y.;Chung, S.U.;Jung., E.S.;Jung, P.M.;Cho, M.H.
    • Advances in pediatric surgery
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    • v.7 no.2
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    • pp.147-156
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    • 2001
  • Membership qualifications and recognition of the subspecialty training programs by the Korean Association of Pediatric Surgeons(KAPS) have been determined by criteria based on the number of neonatal and total pediatric surgical cases registered, since 1989 (Index cases). The numbers are based on a survey of the 14 founding members of the society by Jung et al. in 1987. The current survey is to review the present status of the index cases from 1997 to 1999 among 36 members of the KAPS. Two surveys were undertaken for this study. In the first survey, cases were collected by the registration form, composed of neonatal(N), important pediatric surgical cases (I), tumor and other similar operations(T) and other common pediatric surgical cases(O). Thirty members responded. and the result was discussed at the Topic Discussion section of the 15th Annual Congress of KAPS, 2000. The second survey analyzed additive data, proposed during discussion at the Congress. Twenty-three members responded. This report is the analysis of the both surveys. The average numbers of the cases/year/surgeon of N, I, T, O and total were 19.5, 51.8, 9.5, 77.1 and 356.5. respectively. The number of index cases(N+I+T)/year/surgeon was 80.8. The ratio of (N+I+T)/total cases was 0.3. Seventeen of 30 members have more than 20 cases of N per year. Twelve members have more than 150 cases, and 13 do more than 100 cases of I per year. Fourteen members have more than 10 cases of T per year. Nineteen and 10 members experienced more than 150 and 100 of index cases(N+I+T) per year. A new list of the index cases and coding system are proposed for the future regular update.

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Ecological Characteristics of Rhodotypos scandens Habitat in Imsil-gun, Jeollabuk-do, Korea (전라북도 임실군 병아리꽃나무 자생지의 생태적 특성)

  • Park, Kyung-Uk;Beon, Mu-Sup;Oh, Hyun-Kyung;You, Ju-Han
    • Journal of Environmental Impact Assessment
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    • v.24 no.4
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    • pp.352-366
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    • 2015
  • The purpose of this study is to offer the basic data to the habitat conservation and management by surveying and analysing the ecological characteristics such as the flora, vegetation structure and soil of Rhodotypos scandens habitat. The flora were summarized as 131 taxa including 57 families, 99 genera, 107 species, 1 subspecies, 17 varieties and 6 forms. The life forms grouped as in the follows; the megaphanerophytes(MM) were 21 taxa, 24 taxa of the microphanerophytes(M), 30 taxa of nanophanerophytes(N), 6 taxa of chamaiphytes(Ch), 20 taxa of hemicryptophytes(H), 17 taxa of geophytes(G), 12 taxa of therophytes(Th) and 1 taxa of hydrophytes(HH). The present conditions of communities were 8 types including Zelkova serrata, Quercus aliena, Ulmus parvifolia, Rhamnella frangulioides, Castanea crenata, Albizia julibrissin, Celtis sinensis and Robinia pseudoacacia. In case of the dominant species by layers, the tree layer species were Zelkova serrata, Quercus aliena, Ulmus parvifolia, Castanea crenata, Albizia julibrissin, Celtis sinensis and Robinia pseudoacacia, and the subtree layer species were Rhamnella frangulioides, Q. aliena, Z. serrata, A. julibrissin, U. parvifolia and Broussonetia kazinoki. The shrub layer species was Rhodotypos scandens. In the results of analyzing the diversity index, $H^{\prime}{_{max}}$ from 1.691 to 2.610, from 2.197 to 3.466 in H'max, from 0.646 to 0.903 in J' and from 0.097 to 0.354 in D. In the results of analysing the soil, there showed that acidity was 5.6, 0.5dS/m of electrical conductivity(EC), 59.1mg/kg of available $P_2O_5$, 49.7% of organic matter content, $0.4cmol^+/kg$ of exchangeable $K^+$, $13.5cmol^+/kg$ of exchangeable $Ca^{2+}$, $3.3cmol^+/kg$ of exchangeable $Mg^{2+}$.