• Title/Summary/Keyword: V(IV)

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A COMPARATIVE STUDY OF THE RESISTANCE TO DISLODGEMENT OF FIXED PROSTHESES USING $BIO-PIN^{(R)}$ ($Bio-pin^{(R)}$을 이용한 고정성 보철물의 탈락저항강도의 비교연구)

  • Yi Jong-Won;Cho In-Ho;Lee Jong-Hyuk;Kim Seung-Ki
    • The Journal of Korean Academy of Prosthodontics
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    • v.43 no.2
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    • pp.176-190
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    • 2005
  • Statement of problem. The current trend in prosthodontics is the adoption of a conservative approach to preparing dental prostheses by minimizing the amount of sound tooth structure removal during preparation. Purpose. The major disadvantage of the adhesion bridge is the inherently poor resistance to dislodgement that its use in areas subjected to high occlusal load is limited. The purpose of this study was to compare the dislodgement resistance of $Bio-pin^{(R)}$, conventional 3-unit and adhesion bridges. Material and methods. The experimental groups were classified as follows : Group I : 3-unit bridge cemented using $Super-Bond^{(R)}$ C&B Group II : Adhesion bridge cemented using $Super-Bond^{(R)}$ C&B Group III : $Bio-pin^{(R)}$ design adhesion bridge without incorporation of $Bio-pin^{(R)}$ (cemented using $Super-Bond^{(R)}$ C&B) Group IV-1 : $Bio-pin^{(R)}$ retained adhesion bridge incorporating a single $Bio-pin^{(R)}$ (cemented using $Super-Bond^{(R)}$ C&B) Group IV-2 : $Bio-pin^{(R)}$ retained adhesion bridge incorporating a single $Bio-pin^{(R)}$ (cemented using $Panavia^{(R)}$ F) Group V : $Bio-pin^{(R)}$ retained adhesion bridge incorporating two $Bio-pins^{(R)}$ (cemented using $Super-Bond^{(R)}$ C&B) Results. The results of this study were as follows : 1. Significant differences in dislodgement resistance of the restorations were found between Group I, Group II and Group III (p<0.05). No significant differences in dislodgement resistance of the restorations were observed between Group I Group IV-1 and Group V. However, there were significant differences in dislodgement resistance between Group II and the other groups (p<0.05). 2. No significant differences in dislodgement resistance of the restorations were observed between GroupIV-1 and GroupIV-2, both of which utilized a single $Bio-pin^{(R)}$. However, significant differences were observed when Group III was compared to either GroupIV-1 or Group V (p<0.05). 3. No significant differences in dislodgement resistance relative to the type of dental cements used were found. Conclusion. From the above results, it is concluded that the dislodgement resistance of $Bio-pin^{(R)}$ bridge restorations utilizing a single $Bio-pin^{(R)}$ is similar to that of a conventional 3-unit bridge. The results also suggest that $Bio-pin^{(R)}$ bridge restorations using a single $Bio-pin^{(R)}$ are a viable alternative to the conventional 3-unit bridge when minimal removal of sound tooth structure and fulfillment of both function and esthetic aspects are considered.

CYTOTOXIC EFFECT OF SALVIA MILTIORRHJZA ROOT AGAINST L1210 CELL (단삼의 L1210 세포에 대한 세포 독성의 연구)

  • Sun Jung-Key;Shin Min-Kyo
    • Journal of Oriental Neuropsychiatry
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    • v.3 no.1
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    • pp.84-90
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    • 1992
  • Solvent and TLC-fractionations of the root of Salvia miltiorrhiza have yielded the results as follows ; Solvent fractions Petr. ether Ether Ethy1 acetate Water Control 100uL 0 0.2 35.1 41.9 43.0 50ul 0.7 3.7 37.2 42.0 TLC-fractionation and the Cytotoxic activity Fractions I II III IV V VI Petr. ehter Control 100uL13.0 7.1 16.8 1.2 30.9 23.2 0.5 48.3 50uL 37.1 26.1 30.0 20.1 45.7 27.2 29.7 Among the solvent fractions the petroleum ehter fraction corresponding to the concentration of 20ug/ml has showed the strongest Cytotoxic activity. (no cell survived) A double dilution of the fraction(10ug/ml) still showed strong activity.(0.2 cells survived) The ether fraction contained strong activity. Of the fraction which have veen obtained by a prcparative silicagel TLC I, II, III & IV were cytotoxic, but V and VI were inactive Howevcr, it is worthwhile to note that no one of these has no strong Cytotoxicity as the pertoleum ether fraction itself. This observation says that the active fractions could be additive or synergic to each other. The most active fraction, IV, was scrached out from the TLC and its UV-spectrum taken. The absorption maxima were 207 and 272 nm, indicating the presence of a flavanone strucuture.

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Spermatogenesis and its fine structure of the seminiferous epithelium in the Jindo dog (진도견(珍島犬) 정세관상피(精細管上皮)의 정자발생(精子發生)과 미세구조(微細構造))

  • Kim, Yong-hwan;Park, Young-seok
    • Korean Journal of Veterinary Research
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    • v.33 no.1
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    • pp.23-36
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    • 1993
  • To investigate the cycle and relative frequences and the fine structure of seminiferous epithelia in mature Jindo dogs, histologic study was performed. The results obtained were summarized as follows; 1. Type A spermatogonia appeared approximately 1.6 times as many at stage II as compared to stage I while type In spermatogonia appeared small amount in stage III, IV and V. type B spermatogonia were found during the stage VI to VIII, though not detectable during stage I to V. The type B spermatogonia divided at stage VII to produce the preleptotene primary spermatocytes at stage VIII. The number of primary spermatocytes of the leptotene phase markedly increased during stage I to II, and the primary spermatocytes of the pachytene phase were shown the least in number at stage IV. The secondary spermatocytes could be seen only at stage IV. 2. The relative frequencies of each stage from stages I to VIII of the cycle of seminiferous epithelia were 31.6, 11.9, 10.0, 3.2, 8.2, 10.1, 11.7 and 13.2% respectively. 3. On electron microscopic observations, acrosomal vesicle of spermatids appeared larger though the bulk of germ cells were the morphologically same as those of the other animal species. Thread line structures light microscopically observed in the cytoplasm of Sertoli cell were the longitudinal orientation of mitochondria.

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The Assessment of Wastewater Treatment and Management Using Performance Indicators and Cluster Analysis (수행능 지표(Performance Indicator)와 군집분석을 이용한 하수도시설 및 운영 평가)

  • Kim, Shin-Geol;Choi, Tae-Yong;Koo, Ja-Yong
    • Journal of Korean Society of Water and Wastewater
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    • v.21 no.2
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    • pp.165-175
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    • 2007
  • Performance indicators haven't been used for the assessment of the wastewater treatment facility or management in Korea yet, therefore they are going to be important parts in wastewater utilities because they are used to understand present situation and to compare one with other wastewater utilities. In this study, we used performance indicators to assess the condition of wastewater utilities and they were divided into four categories (A, B, C, and D). A category represented the condition of the planning & construction and composed of wastewater supply, disaster defence and employees. B category represented maintenance of wastewater utilities and were composed of manhole, sewer, and technical employees. C category showed the operation efficiency of wastewater utilities and D category represented the environmental load. To analyze the situation of wastewater utilities overall, cluster analysis was performed using four categori' es indicators. And CCC (Cubic Clustering Criterion) and R-square were used to decide the proper number of clusters, and wastewater utilities of 48 cities were divided into 5 groups(I, II, III, IV, and V groups). Each cluster was analyzed by average and standard deviation to understand the situation of wastewater utilities. A group analysis showed that IV and V clusters were insufficient, B group showed that I and IV groups were insufficient, C group showed all clusters are above average, and D group was also like C group.

Studies on the Molybdenum Complexes with Tetradentate Schiff Base Ligand (I). N,N'-bis (Salicylaldehyde)-ethylene Diimine (네자리 Schiff Base 리간드의 몰리브덴착물에 관한 연구 (제1보))

  • Jo, Gi Hyeong
    • Journal of the Korean Chemical Society
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    • v.18 no.4
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    • pp.267-271
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    • 1974
  • The tetradentate schiff base, N,N'-bis(salicylaldehyde)-ethylene diimine has been reacted with a series of Mo(IV), Mo(V), Mo(IV), and Mo(III) oxidation states to form new Complexes; $[MoO_2(C_{16}H_{14}O_2N_2)], (MoO(C_{16}H_{14}O_2N_2)]_2O, (Mo(SCN)(C_{16}H_{14}O_2N_2)]_2O, and (Mo(H_2O)(C_{16}H_{14}O_2N_2)]_2O.$ These complexes have hexa coordinated configurations and the mole ratio of these ions to the ligand was 1:1. These complexes have been identified by visible spectra, infrared specra, T.G.A., D.T.A., and elemental analysis.

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Structure and Physical Property of the Crust of Mid-west Korea: Analysis of Sedimentary Basins in the Namyang and Tando Areas, Kyeonggi Province, Korea (한반도 중서부 지각구조와 물성 연구: 경기도 화성군 남양 및 안산시 탄도지역에 분포하는 퇴적분지의 분석)

  • Park, Sung-Dae;Chung, Gong-Soo;Jeong, Ji-Gon;Kim, Won-Sa;Lee, Dong-Woo;Song, Moo-Young
    • Journal of the Korean earth science society
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    • v.21 no.5
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    • pp.563-582
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    • 2000
  • Two Cretaceous(80-90 Ma) non-marine sedimentary basins, Namyang and Tando Basins, are distributed in the Namyang area, Hwaseonggun and in the Tando area, Ansanshi, Kyungki Province, Korea. The Namyang and Tando Basins are composed of 10 facies, which are pooped into 5 facies associations(FA). FA I consists of massive conglomerate facies, normally graded conglomerate facies and reversely graded conglomerate facies, which is interpreted to have been formed by laminated sandstone facies, massive conglomerate facies(channelized), which is thought to have been formed by sheet flow, stream flow and suspension sedimentation in an alluvial/braided plain environment. FA III consists of massive mudstone(pebbly) facies, laminated mudstone facies, massive sandstone facies and is interbedded by channel-fill conglomerate. It is interpreted to have been deposited by suspension settling during flooding and channel-fill deposition in a floodplain environment. FA IV consists of massive conglomerate facies, normally graded conglomerate facies, massive sandstone facies, normally graded sandstone facies, and laminated sandstone facies and is interbedded with mudstone facies. It is thought to have been deposited by debris flow and turbidity current in a fan-delta environment. FA V consists of massive mudstone facies, laminated mudstone facies, laminated sandstone facies and is interbedded by massive conglomerate bed. It is thought to have been formed by suspension sedimentation and low-density turbidity current in a lake. In the Namyang Basin FA I is distributed in the eastern and southern margin of the basin, FA II in the middle part of the basin as north-south tending band. and FA III in the western part. In the Tando Basin FA II is distributed in the middle part of eastern margin and in the northwestern margin, FA IV in the southwestern part, and FA V in the central part. Correlation of the facies associations shows that FA I and II in the Namyang Basin are distributed in the lower to middle part of stratigraphic sequence and FA III in the upper part of the sequence whereas FA II and IV in the Tando Basin are in the lower to middle part and FA V in the upper part of the sequence. These patterns of facies associations distribution suggest that the Namyang Basin was developed as an alluvial fan and alluvial/braided plain at first and then evolved into a floodplain whereas the Tando Basin was developed as a fan-delta and alluvial/braided plain at first and then evolved into a lake environment.

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쌍끌이 중층트롤어업의 연구 ( IV ) ( a Study on the Midwater Pair Trawling ( IV )

  • Jang, Chung-Sik;Lee, Byeong-Gee
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.32 no.1
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    • pp.7-15
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    • 1996
  • Full scale experiment was carried out in the southern sea of Korea to compare some important factors tested in the model experiment. The results obtained can be summarized as follows ; 1. The changing aspect of mouth performance of the full scale net was almost coincided with the results obtained by the model experiment. The vertical opening(H) and the opening area(S) can be expressed as a function of the towing velocity(V) as H=48.78. $e^0.38V$(unit: m, k't) S= 1,443 .$e^-0.25V$(unit: $m^2V$, k't) 2. The changing aspect of working depth of the full scale net was almost coincided with the results obtained by the model experiment. The depth(D) can be expressed as a function of the towing velocity(V) and the warp length(L) as D=92.49.$V^1.37$(unit: m, k't, L= 150m) D= 12.07+0.32. L (unit: m, V=2k't) [)= - 7.90+0.22 . L (unit: m, V=3k't) 3. Some problems were found to operate A - type full scale net by common bottom pair trawlers. The problems can be summarized as follows; (1) Entangling of wing and square head ropes while net casting.(2) Man power needed and time spent for net hauling by common bottom trawlers increased considerably.( 3) Tearing of nettings caused by over -load of tension and entangling of net pendant while net hauling. To solve these problems, the trawlers are favorable to be equipped with variable pitch propeller and llet drum. While the net is favorable to be constructed with trifurcated net pendant in stead of quadrifurcated net pendant used at present.

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A Model on the Determinants of Visual Preference at Golf courses (경관의 선호도 결정인자 모형 -골프장을 배경으로-)

  • 서주환;이철민;맹상빈
    • Journal of the Korean Institute of Landscape Architecture
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    • v.29 no.1
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    • pp.1-10
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    • 2001
  • The purpose of this thesis is to classify landscape-type of golf course, and t provide a better understanding of landscape of existing golf courses, seek a developed method for landscape, and other useful knowledge. In order to classify landscape type of the golf course, and analyze the preference for the determinants, we have selected 4 golf courses in Yongin, Kyonggi Province. The analysis in this study shows that a variable, 'familiarity' is the most potent influence of visual preference, (Sig 0.01), and it can be divided into five classes of landscape-type in golf course. More specifically, we conducted the analysis of the image of views and visual preference to bring out major factors which could decide visual preference in golf courses. The results between visual preference and physical variable are as follows; 1. It implies that a factor for a image of the view in golf course is analyzed by 4 districts from factor 1 to factor 4. An ability explaining those factors in the whole of variable quantity is 51.742%, implying factors for the image of the scene in golf courses are appeared as familiarity, changeableness, spaciousness, and naturalness. Among those factors, since familiarity(C.V.; 26.783%) and changeableness(C.V.; 112.200%) took high rank, this represents the fact that familiarity or changeableness highly affects the forming of image. 2. Defending on degree of image ability in golf course, we could classify as five types such as Type I, Type II, Type II, Type IV, and Type V. 3. As a result of calculating type of factor score, Type I had the lowest ranking in naturalness, and rather lower than others such as organization and spaciousness. The II is a top-ranked one in familiarity and naturalness, while it has the lowest ranking in spaciousness. Type III has the highest ranking in organization and preference. Type IV is the lowest-ranked one in familiarity and preference. Type IV is the lowest-ranked one is familiarity and preference. Type V has the highest ranking in spaciousness, but the lowest ranking in organization. 4. As a result of preference, Type III, Type II, Type V, Type I, and Type IV come out in order. That water-seen place type charges the highest rank shows the importance of changeable materials. 5. These factors-familiarity, organization, spaciousness and naturalness- are the major materials of the scene of view in golf courses. The possibility of how to use those for designing and making enhanced golf courses should be reinvestigated through these factors. Especially, it is acknowledged that the duction of changeableness, which is not mentioned in the study of informational approach, is much stimulating for the designing use. A further research on this theme should be made in the future, not limiting to the golf courses in Yongin.

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Studies on the synthesis and antitubercular activity of acyl derivatives of isonicotinic acid hydrazide (Isonicotinic acid hydrazide의 acyl 유도체 합성및 항균작용에 관한 연구)

  • 고현기
    • YAKHAK HOEJI
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    • v.13 no.1
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    • pp.43-46
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    • 1969
  • Five new acyl derivatives of isonicotinic acid hydrazide such as N-(2,4-dichlorophenoxyacetyl)-isoniotinic acid hydrazide (I), N-(p-nitrobenzoyl)-isonicotinic acid hydrazide (II), N-benzoylisonicotinic acid hydrazide (III), N-furoylisonicotinic acid hydrazide (IV) and N-(p-aminobenzoyl)-isonicotinic acid hydrazide (V) were synthesized. They were obtained by the action of 2,4-dichlorophenylacetyl chloride, p-nitrobenzoyl chloride, benzoyl chloride, furoyl chloride and p-aminobenzoyl chloride with isonicotinic acid hydrazide in pyridine solution. Evaluated for their in vitro antitubercular activity against Mycobaterium tuberculosis H$_{37}$ R$_{\upsilon}$ N-furoylisonicotinic acid hydrazide (IV) showed antitubercular activity at 1${\gamma}$/ml.

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학습양식에 따른 집단 구성이 수학 성취도와 태도에 미치는 효과

  • Han, Gil-Jun;Seo, Jong-Jin
    • Communications of Mathematical Education
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    • v.15
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    • pp.287-292
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    • 2003
  • 본 연구는 중학생을 대상으로 협동 학습에서 사용하고 있는 기존의 집단 구성과는 달리 학생들의 학습 양식에 따라 집단을 구성하여 협동 학습의 효과성을 보이고자 하였다. 학습양식(Learning Style)에 따라 집단을 구성한 협동 학습의 결과는 다음과 같다. 첫째, 학습양식에 따라 구성한 협동 학습 집단( I, II, III, IV)이 일반학습 집단(V)에 비하여 수학 성취도에 있어서 유의한 효과를 보였다(p<.001). 둘째, 학습양식에 따라 구성한 협동 학습 집단( I, II, III, IV)이 일반학습 집단에 비하여 수학에 대한 긍정적인 태도로의 변화가 있었다(p<.001).

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