• Title/Summary/Keyword: cavity expansion

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Changes in CGRP-immunoreactive Nerve Fibers during Expansion of Midpalatal Suture of the Rat (백서 정중구개봉합 확대후의 CGRP 면역반응 신경섬유의 변화)

  • Kim, Bo-Kyung;Park, Kuk-Pil;Kyung, Hee-Moon;Kwon, Oh-Won;Sung, Jae-Hyun
    • The korean journal of orthodontics
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    • v.29 no.1 s.72
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    • pp.73-81
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    • 1999
  • Midpalatal suture expansion is often used for patients haying narrow maxillary arch, cleft palate, respiratory handicap with narrow nasal cavity. CGRP has been known as a modulator of pain transmission in central nervous system and a local effector to peripheral tissue causing vasodilation, increase of blood flow, modulation of immune system, regulation of macrophagic function and stimulation of bone formation. To investigate changes of CGRP-immunoreactive nerve fibers in midpalatal suture during the expansion, immunohistochemical study was performed by using rats. Experimental rats (10 weeks, 250 gm) were divided into five groups (control, 1, 4, 7, 14 days group (each n=4) and applied orthodontic force (approximately 200gm) to upper anterior incisors. Frozen sections of midpalatal suture area were immunostained by using rabbit antisera. The results were as follows. ${\cdot}$ The CGRP-immunoreactive nerve fibers were hardly observed in control group. ${\cdot}$ In 1 day group, the CGRP-immunoreactive nerve fibers were more increased around the vessels than control group. ${\cdot}$ In 4 days group, the CGRP-immunoreactive nerve fibers were more increased than control group, but not more increased than 1 day group. Vascular diameter was more enlarged. ${\cdot}$ In 7 days group, especially, hematoxilin affinity of cells was remarkable and cells were arranged along the bone margin. The CGRP-immunoreactive nerve fibers were more reduced than 4 days group and vascular diameter was also reduced. ${\cdot}$ In 14 days group, the CGRP-immunoreactive nerve fibers were similar to those of 7 days group and the irregularity of bone margin was almost recoverd. In Conclusion, the CGRP-immunoreactive nerve fibers nay be related to initial neurogenic inflammatory reaction in expanding mid-palatal suture.

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Electrochemical Performance of CB/SiOx/C Anode Materials by SiOx Contents for Lithium Ion Battery (SiOx 함량에 따른 CB/SiOx/C 음극재의 전기화학적 특성)

  • Kim, Kyung Soo;Kang, Seok Chang;Lee, Jong Dae;Im, Ji Sun
    • Applied Chemistry for Engineering
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    • v.32 no.1
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    • pp.117-123
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    • 2021
  • In this study, the composite was prepared by mixing SiOx, soft carbon, and carbon black and the electrochemical properties of lithium ion battery were investigated. The content of SiOx added to improve the capacity of the soft carbon anode material was varied to 0, 6, 8, 10, 20 wt%, and carbon black was added as a structural stabilizer for reducing the volume expansion of SiOx. The physical properties of prepared CB/SiOx/C composite were investigated through XRD, SEM, EDS and powder resistance analysis. In addition, the electrochemical properties of prepared composite were observed through the charge/discharge capacity, rate and impedance analysis of the lithium ion battery. The prepared CB/SiOx/C composite had an inner cavity capable of mitigating the volume expansion of SiOx by adding carbon black. The formed internal cavity showed a low initial efficiency when the SiOx content was less than 8 wt%, and low cycle stability when the content of SiOx was less than 20 wt%. The CB/SiOx/C composite containing 10 wt% of SiOx showed an initial discharge capacity of 537 mAh/g, a capacity retention rate of 88%, and a rate of 79 at 2C/0.1C. SiOx was added to improve the capacity of the soft carbon anode material, and carbon black was added as a structural stabilizer to buffer the volume change of SiOx. In order to use the CB/SiOx/C composite as a high-efficiency anode material, the mechanism of the optimal SiOx and the use of carbon black as a structural stabilizer was discussed.

A Study on Pullout-Resistance Increase in Soil Nailing due to Pressurized Grouting (가압 그라우팅 쏘일네일링의 인발저항력 증가 원인에 관한 연구)

  • Jeong, Kyeong-Han;Park, Sung-Won;Choi, Hang-Seok;Lee, Chung-Won;Lee, In-Mo
    • Journal of the Korean Geotechnical Society
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    • v.24 no.4
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    • pp.101-114
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    • 2008
  • Pressurized grouting is a common technique in geotechnical engineering applications to increase the stiffness and strength of the ground mass and to fill boreholes or void space in a tunnel lining and so on. Recently, the pressurized grouting has been applied to a soil-nailing system which is widely used to improve slope stability. Because interaction between pressurized grouting paste and adjacent ground mass is complicated and difficult to analyze, the soil-nailing design has been empirically performed in most geotechnical applications. The purpose of this study is to analyze the ground behavior induced by pressurized grouting paste with the aid of laboratory model tests. The laboratory tests are carried out for four kinds of granitic residual soils. When injecting pressure is applied to grout, the pressure measured in the adjacent ground initially increases for a while, which behaves in the way of the membrane model. With the lapse of time, the pressure in the adjacent ground decreases down to a value of residual stress because a portion of water in the grouting paste seeps into the adjacent ground. The seepage can be indicated by the fact that the ratio of water/cement in the grouting paste has decreased from a initial value of 50% to around 30% during the test. The reduction of the W/C ratio should cause to harden the grouting paste and increase the stiffness of it, which restricts the rebound of out-moved ground into the original position, and thus increase the in-situ stress by approximately 20% of the injecting pressures. The measured radial deformation of the ground under pressure is in good agreement with the expansion of a cylindrical cavity estimated by the cavity expansion theory. In-situ test revealed that the pullout resistance of a soil nailing with pressurized grouting is about 36% larger than that with regular grouting, caused by grout radius increase, residual stress effect, and/or roughness increase.

Study on Confectionary Properties of Chou made with Flour of Rice and Rice-Wheat mixture (미분을 이용한 chou의 제과특성 연구)

  • 김명애;오승희
    • Korean journal of food and cookery science
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    • v.11 no.1
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    • pp.69-76
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    • 1995
  • This study was concentrated on the subject of chou formation and physicochemical characteristics on medium flour mixed with 0, 25, 50, 75, 100% of rice flour in order to clarify the possibility to substitute rice flour for wheat flour on chou preparation. The water holding capacity, swelling power, and maximum viscosity were higher in rice flour than those in medium flour but the initial pasting temperature was equal to 65$^{\circ}C$ in the two flour groups. The ratio of setback during cooling became 0.94 in the rice flour and 1.14 in the medium flour. So, the rice flour showed a slow tendency during gel formation as compared with the medium flour. The volumes of the rice choux were ranged from 80.0% to 89.0% according to the mixing ratio of medium flour as compared with that of the chou of wheat flour. But, the choux formation were increased as much as 108.8% out the paste added gelation of glutinous substance and 124.4% at the paste added Span20 of emulsifier compared to the non-addition treatment. The paste of rice flour added gelatin and Span20 showed better dispersion of components, especially, the small granules of lipid were fairly or plentifully dispersed in the paste added Span20 due to emulsifying activity. In sensory evaluation, the chou of l00% rice flour was inferior to that of medium flour on cavity-forming but the choux of wheat flour mixed with 25%, 50%, and 75% of rice flour were equal or superior to that of medium flour on all characteristics tested such as appearance, surface color, cavity-forming, chewiness, and taste. There were no significant differences on the cavity-forming expansion and taste between choux of rice flour and wheat flour Therefore, the results of this study made conclusion that rice flour would be substituted for wheat flour on the chou preparation.

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Evaluation on Bearing Resistance of Transverse Members in Steel Strip Reinforcement using Pullout Tests and Theoretical Equations (인발시험과 이론식을 이용한 강재스트립 보강재에 설치된 지지부재의 지지저항 특성 평가)

  • Han, Jung-Geun;Yoon, Won-Il;Hong, Ki-Kwon;Hong, Won-Pyo;Lee, Kwang-Wu;Cho, Sam-Deok
    • Journal of the Korean Geosynthetics Society
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    • v.9 no.2
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    • pp.33-40
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    • 2010
  • In this study, the pullout tests are conducted to evaluate pullout resistance of steel strip reinforcement with transverse members. The test results are compared with theoretical equations and then the failure mechanism of transverse members is evaluated. The bearing resistance stress(${\sigma}^{\prime}_b$) of transverse members, which is applied pullout force at 50mm displacement, is closed from punching shear failure to general shear failure. The behavior by increment of a number of transverse members became closer to general shear failure. The behavior of transverse members at maximum pullout force, which is closed to general shear failure, is indicated that it is unrelated to normal stress and a number of transverse members. However, if the allowable displacement of reinforced soil wall is considered, it is impossible to apply in design. The test results are compared with bearing resistance evaluations using Prandtl's plastic theory and cylindrical cavity expansion theory. The analysis results are indicated that the bearing resistance by pullout tests is closed to predicted result by Prandtl's plastic theory, which are located between general shear failure and punching shear failure.

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A CLINICAL AND RADIOGRAPHIC STUDY OF DENTIGEROUS CYSTS (함치성 낭의 임상 방사선학적 연구)

  • Lee Kang-Sook;Choi Karp-Shik
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.25 no.2
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    • pp.399-408
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    • 1995
  • The purpose of this study was to obtain information on the clinical and radiographic features of the dentigerous cysts in the jaws. For this study, the authors examined and analysed the clinical records and radiographs of 233 patients who had lesions of dentigerous cyst diagnosed by clinical and radiographic or histopathological examinations. And the obtained results were as follows: 1. Dentigerous cysts occurred the most frequently in the 2nd decade(38.2%) and occurred more frequently in males(67.4%) than in females(32.6%). 2. The most common clinical symptom was swelling of the jaw(33.9%), and the lesions were treated by the method of surgical removal. 3. The type of lesions was mainly observed as central type(72.5%), and size of the lesion was most frequently observed 2 - 2.9cm in the widest length. 4. The lesions were most frequently observed well-defined outline with hyperostotic border(49.8%), and smooth margin(73.4%), and homogeneous lesional radiolucency(79.4%). 5. Cortical thinning and expansion of the lesions(82.0%) were observed, and their direction were most frequently observed toward buccal side(64.0%). 6. The effect on the causative tooth were observed as tooth displacement(41.2%) and delayed root development(l9.3%), and the distance between cemento-enamel junction and lesional wall attachment of the causative tooth was mainly observed as below 2mm(79.6%). 7. The effect on the adjacent tooth were observed as loss of lamina dura(66.8%), root resorption(33.9%), and tooth displacement(31.5%). 8. The effects on the adjacent anatomic structures were observed as displacement of the mandibular canal(46.5%) and maxillary sinus or nasal cavity(72.2%).

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Evaluation of Weathering Intensity and Strength Parameter for Weathered Granite Masses (I) (화강 풍화암의 풍화도 및 강도정수의 평가 (I))

  • 이종규;장서만
    • Journal of the Korean Geotechnical Society
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    • v.19 no.2
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    • pp.227-236
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    • 2003
  • The evaluation of the reliable strength and deformation characteristics of weathered granite masses is very important for the design of geotechnical structure under working stress conditions. Various types of laboratory test such as triaxial compression test can be performed to determine the strength parameters. However, it is very difficult to obtain the representative undisturbed samples on the site and also the rock specimen cannot represent rock mass including discontinuities, fracture zone, etc. This study aims to investigate the strength and deformation characteristics of granite masses corresponding to its weathering and develop a practical strength parameter evaluation method using the results of PMT. To predict weathering intensity and strength parameters of the weathered granite masess in the field, various laboratory tests and in-situ tests including field triaxial test and PMT are carried out. Based on the results of weathering index tests, the classification method is proposed to identify the weathering degree in three groups for the weathered granite masses. Using the analytical method based on the Mohr-Coulomb failure criteria and the cavity expansion theory, the strength parameters of rock masses were evaluated from the results of PMT. It shows that weathering intensity increases with decreasing the strength parameters exponentially. The strength parameters evaluated with the results of PM almost coincide with the results of field triaxial test.

Studies on the phrases of Yellow Emperor's internal classic(黃帝內經) for the physiology on the spleen and stomach (비위생리(脾胃生理)에 수용(授用)되는 황제내경(黃帝內經) 어구(語句)에 관(關)한 연구(硏究))

  • Won, Jin-Hui
    • The Journal of Korean Medicine
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    • v.16 no.2 s.30
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    • pp.453-489
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    • 1995
  • The research of the phrases related with physiology of stomach and spleen in the contents of Huang Di Nei Jing(黃帝內經) known as the Bible of oriental medicine will make a contribution to a deep understanding of disease of stomach and spleen and a proper clinical diagnosis and treatment of them. In this research of the most appropriate glosses recorded nine kinds of representative medical books including Huang Di Nei Jing Somoon(黃帝內經素問) of Wang Bing(王氷) were picked out: The summaries of the selected contents are as follows: 1. The word 'saliva(涎)' in 'the spleen controls saliva(脾爲涎)' can be viewed as a generic term referring to oral cavity secretion gland as well as the secretion fluid of salivary gland. 2. The phases 'a large reservoir(太倉)', barn organs', 'a reserboir of food stuff', 'a stomach as the market(胃爲之市)', etc mean the function of stomach to receive food(胃主受納). 3. The phase 'generation of five tastes(五味出焉)' means both 'the function of stomach to transform food into chyme(胃主腐熟)' and 'the channelling function of spleen.(脾主運化)' 4. The flowing of the food-Qi(食氣) into stomach brings about spreading Jung(精) into liver and then percolating Jung(精) flow into channel. The channel-Qi(脈氣) flows into lung through channel. As a result, all kinds of channels gather together in lung and Jung(精) is sent into skin and hair. The assembly of Jung(精) with skins and channels moves Qi(氣) into fu-organ and so jung(精) and mental activity(神明) in fu-organ(府) come to be in four organs(四臟). Then if Qi(氣) comes back to power balance unit(權衡) being in the state of equilibrium(權衡以平), the hole of Qi(氣口) comes to determine the matter of life and death through achieving Chun-quan-chi(-寸-關-尺). The above mentioned phrases means the digestion, asorption and transmission of food. When food is taken in stomach, Jung-Qi(精氣) comes to be over flowed upward into spleen, back into lung, finally downward into bladders through water-conduit(水道) controlled by lung. When water- Jung(水精) radiates into whole body with channels of five organs(五臟), both of them fit together with and yin-yang(陰-陽). Therefore, the grasping of the rise and decline of yin-yang(陰C-陽) is necessary to consult patients. The above mentioned phrases is properly viewed to designate the asorption, transmission and excretion of food. 5. Spleen controls flesh(脾之合肉也), the state of spleen is known by human lips, and what this means is that liver plays functions of spread and expansion(肝主疏泄). 6. The phrase 'Jung Jung'((中精)) in 'gallbladder dominates Jung jung(膽主中精)', which in one of the specific expression of 'liver plays functions of spread and expansion(肝主疏泄). 7. It is right that the phase 'The eleven organs in all are determined by gallbladder'(凡十,一臟取決於膽也) is correctly paraphrased as 'only one of ten organs, spleen, is determined by gallbladder'.(凡十,一臟取決於膽也), 8. The small intestine is an organ. which receives the materials digested and sends them out. This means that the function of transforming materials(化物) factually refers to that of separating clearity and blur(泌別淸濁). And it is also thought to have the function of ascending clearity and descending blur(升淸降濁), 9. A large intestine is a transmitting organ(傳導之官) from which a change comes out(變化出焉). the phrase 'change'(變化) in this sentence means both the intake of water and nutrition and the formation procedure of stool through excretion of mucocele.

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