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The Effect of the Uncariae Ramulus et Uncus on the Regeneration Following CNS Injury (중추신경계 손상 회복에 미치는 대한 조구등의 영향)

  • Lee, Jin-Goo;Park, Hyoung-Jin;Kim, Dong-Woong;Song, Bong-Keun
    • Journal of Pharmacopuncture
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    • v.12 no.1
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    • pp.67-76
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    • 2009
  • Objective : Following central nervous system(CNS) injury, inhibitory influences at the site of axonal damage occur. Glial cells become reactive and form a glial scar, gliosis. Also myelin debris such as MAG inhibits axonal regeneration. Astrocyte-rich gliosis relates with up-regulation of GFAP and CD81, and eventually becomes physical and mechanical barrier to axonal regeneration. MAG is one of several endogenous axon regeneration inhibitors that limit recovery from CNS injury and disease. It was reported that molecules that block such inhibitors enhanced axon regeneration and functional recovery. Recently it was reported that treatment with anti-CD81 antibodies enhanced functional recovery in the rat with spinal cord injury. So in this current study, the author investigated the effect of the water extract of Uncariae Ramulus et Uncus on the regulation of CD81, GFAP and MAG that increase when gliosis occurs. Methods : MTT assay was performed to examine cell viability, and cell-based ELISA, western blot and PCR were used to detect the expression of CD81, GFAP and MAG. Then also immunohistochemistry was performed to confirm in vivo. Results : Water extract of Uncariae Ramulus et Uncus showed relatively high cell viability at the concentration of 0.05%, 0.1% and 0.5%. The expression of CD81, GFAP and MAG in astrocytes was decreased after the administration of Uncariae Ramulus et Uncus water extract. These results was confirmed in the brain sections following cortical stab injury by immunohistochemistry. Conclusion : The authors observed that Uncariae Ramulus et Uncus significantly down-regulates the expression of CD81, GFAP and MAG. These results suggest that Uncariae Ramulus et Uncus can be a candidate to regenerate CNS injury.

Numerical Simulation for Prediction of Existing Cavity Location on Earthquake-Induced Building Collapse (지진에 의한 건축물 붕괴 시 매몰공동 위치 예측에 관한 수치해석 사례 연구)

  • Jung, Jahe;Park, Hoon;Kim, Kwang Yeom;Shin, Hyu-Soung
    • The Journal of Engineering Geology
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    • v.25 no.4
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    • pp.613-621
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    • 2015
  • The most urgent measure to be taken for a rapid rescue when a building collapse happens is to designate or predict a possible location where human beings are alive. It is, however, very difficult to find and correctly designate such cavities by conventional geophysical survey due to a pile of debris of building members. In this study, the simulation of building collapse induced by an earthquake was conducted to predict forming pattern of a existing cavities. The simulation cases included the influence of structure wall existence and height of building. Three types of building structure: five-story, ten-story and fifteen-story were prepared as a simulation case. In the case of high building, a collapse range on the inside of the building increased consequently lowering the possibility of lifeguard cavern forming. In addition, when a wall exists in the basement floor, the possibility that existing cavities could be formed increased compared to the cases without wall.

An Example of Changed Design through the Face Mapping and Slope Analysis (절토사면 현황도 작성 및 분석에 따른 설계변경 사례연구)

  • Lee, Byung-Joo;Chae, Byung-Gon;Lee, Kyoung-Mi
    • The Journal of Engineering Geology
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    • v.24 no.1
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    • pp.137-146
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    • 2014
  • The geology of the study area which is located in Samkoe-dong, Dong-gu, Daejeon city comprises black slate, limestone, and pebble-bearing phyllitic rock as meta-sedimentary rocks; and biotite granite and quartz porphyry intrusions. Face mapping revealed sliding in three or four sites of contained coaly slate, where the dip of the foliation and other discontinuities is parallel to the surface slope. The cause of the slope sliding is this parallelism as well as the swelling of the coaly slate when wet. In contrast, the slop on the opposite side of the road is relatively stable because the dip of the foliation and other discontinuities are oblique or normal to the surface slope. To ensure slope stability, a cut-and-cover tunnel was designed and constructed for the new road.

Development of Contact Pressure Analysis Model of Automobile Wiper Blades (차량용 와이퍼 블레이드의 접촉압력 해석모델 개발)

  • Lee, Sangjin;Noh, Yoojeong;Kim, Kyungnam;Kim, Keunwoo;Jang, Youngkeun;Kim, Kwanhee;Lee, Jaecheon
    • Transactions of the Korean Society of Automotive Engineers
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    • v.23 no.3
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    • pp.292-298
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    • 2015
  • A wiper is a safety device removing rain and debris from windshield and ensuring visibility of drivers. If contact pressure distribution between rubber of the blade and the windshield is unbalanced, unwanted noise, vibration, and abrasion of the blade can occur and sometimes fatal accidents could occur. To improve the safety of the wiper, there have been many researches on the contact pressure analysis of the wiper, but the analysis results were not converged or require much computational time due to material nonlinearity of the rubber and contact conditions between the blade rubber and the windshield. In this research, a simple model with 1D beam and 2D shell elements was used for the contact pressure analysis instead of the 3D blade model. The simplified model saved computational time of the analysis and resolved convergence problems. The accuracy of the analysis results was verified by comparing them with experimental results for different rail spring curvatures.

A STUDY ON THE COLOR CHANGES OF DISCOLORED NONVITAL TEETH BY THE NONVITAL BLEACHING TECHNIQUES (표백방법에 따른 번색된 무수치의 색조 변화에 관한 연구)

  • Park, Hyun-Hee;Cho, Young-Gon
    • Restorative Dentistry and Endodontics
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    • v.19 no.1
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    • pp.169-179
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    • 1994
  • The purpose of this study was to compare and evaluate the bleaching efficacy of three nonvital bleaching techniques: Walking bleaching, Walking bleaching and heat application, and Walking bleaching and bleaching light application. 36 extracted anterior teeth with intact crowns were immersed in 5 % sodium hypochlorite solution for twenty-four hours to loosen extrinsic debris. Lingual access openings were prepared in all teeth and the pulps were extirpated. The teeth were stored in 5% sodium hypochlorite for twenty-four hours to open the dentinal tubules and they were stained via whole blood. Once the teeth were stained, they were evaluated with Colorimeter. The teeth in each group were ranked from lightest to darkest and divided equally into three experimental groups in which the following bleaching techniques were used. Intracoronal base was placed 2mm below cementoenamel junction. Group 1 Walking bleaching (Superoxol + Sodium perborate) Group 2 Heat application + Walking bleaching (Superoxol+Sodium perborate) Group 3 Light application+Walking bleaching (Superoxol+Sodium perborate) The bleaching agents were changed every 3 days and the teeth were bleached for a total of 14 days. The teeth were evaluated with Colorimeter before the start of any bleaching and on day 14. The results were as follows: 1. At the end of 14 days, all the sample teeth demonstrated the increase of Lightness Index at cervical 1/3 of crown (p<0.05) Lightness Index was significant difference in group 2 and 3, but there were some minor differences among groups (p>0.05). 2. In all groups, there was significant difference in red chromacity (p<0.05), but there were some minor differences among groups (p>0.05). 3. In all groups, there was no significant difference in yellow chromacity (p>0.05).

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Diversity of Wood-Inhabiting Polyporoid and Corticioid Fungi in Odaesan National Park, Korea

  • Jang, Yeongseon;Jang, Seokyoon;Lee, Jaejung;Lee, Hanbyul;Lim, Young Woon;Kim, Changmu;Kim, Jae-Jin
    • Mycobiology
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    • v.44 no.4
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    • pp.217-236
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    • 2016
  • Polyporoid and corticioid fungi are among the most important wood-decay fungi. Not only do they contribute to nutrient cycling by decomposing wood debris, but they are also valuable sources for natural products. Polyporoid and corticioid wood-inhabiting fungi were investigated in Odaesan National Park. Fruit bodies were collected and identified based on morphological and molecular analyses using 28S and internal transcribed spacer regions of DNA sequences. As a result, a total of 149 species, 69 genera, 22 families, and 11 orders were recognized. Half (74 species) of the species were polypores, and the other half (75 species) were corticioid fungi. Most of the species belonged to Polyporales (92 species) followed by Hymenochaetales (33 species) and Russulales (11 species). At the genus level, a high number of species was observed from Steccherinum, Hyphodontia, Phanerochaete, Postia, and Trametes. Concerning distribution, almost all the species could be found below 1,000 m, and only 20% of the species were observed from above 1,000 m. Stereum subtomentosum, Trametes versicolor, T. hirsuta, T. pubescens, Bjerkandera adusta, and Ganoderma applanatum had wide distribution areas. Deciduous wood was the preferred substrate for the collected species. Sixty-three species were new to this region, and 21 species were new to Korea, of which 17 species were described and illustrated.

Systemic Pemphigus Vulgaris: A Case Report (전신성 심상성 천포창의 치험례)

  • Seo, Bo-Mmie F.;Seo, Je-Won;Oh, Deuk-Young;Ahn, Sang-Tae;Rhie, Jong-Won
    • Archives of Plastic Surgery
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    • v.38 no.5
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    • pp.687-690
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    • 2011
  • Purpose: Pemphigus vulgaris, a rare autoimmune blistering disease of the skin and mucous membranes remains a challenging disease to treat. Management is focused on immunotherapy against autoimmune antibodies that target keratinocyte cell adhesion molecules, and antibiotics preventing secondary infections. There is no established dressing protocol and skin is usually manipulated the least amount possible in order to minimize irritation. The authors suggest that early initiation of aggressive bathing and debridement of skin lesions, with nutritional support, is essential in accelerating resolution. Methods: A 40 year-old male previously diagnosed with pemphigus vulgaris was admitted due to exacerbation of mucocutaneous lesions involving the epidermis and mucosa of the whole body. Steroids, immunosuppressants, intravenous immunoglobulin and antibiotics were administrated, but infection and de-epithelialization progressed, while his general condition deteriorated with a weight loss of over 20 kilograms. The plastic surgery department intervened with daily bathing, debridement of unhealthy debris and non-traumatizing coverage of growing epithelium. Total parenteral nutrition and mobilization with rehabilitation therapy was initiated as early as possible. Results: After bathing, healthy epithelium gradually covered the patient's entire body, while his general condition improved with a corresponding weight gain of 14 kgs. Conclusion: Treatment of pemphigus vulgaris focuses on immunotherapy and infection control. However, an equal amount of attention should be laid on early intervention with daily dressings including bathing and irrigation, nutritional support, and exercise as this accelerates resolution of existing infections, promotes healthy epithelialization and leads to faster recovery.

Construction and Monitoring of Test bed in Urban Sediment Disaster Prevention Technology (도심지 토사재해 방어기술 테스트베드 구축 및 모니터링 연구)

  • Lee, Jung-min;Kim, Hyo-Jin;Lee, Yoon-Sang;Jin, Kyu-Nam
    • Land and Housing Review
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    • v.8 no.3
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    • pp.161-169
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    • 2017
  • In this study, sediment transfer and precipitation analysis of the test bed watershed was conducted through the model for the application and practical use of the urban sediment disaster prevention technology, and used this as an aid to design to secure reliability. In addition, conducted the test bed monitoring with the defense technology, analyzed the effect, and established the maintenance plan. Analyzed the change of soil deposition volume through arbitrary slope adjustment for the currently installed stormwater conduit of the test bed watershed. As a result, it is important to reduce the total sedimentation amount in the adjustment of the slope of the entire pipeline, but it is important that the sedimentation depth of each sediment does not rise to such a degree as to threaten the performance of the pipeline. Considering these matters, it is necessary to design the pipeline to prevent the clogging of the soil from the viewpoint of the reliability of the entire pipeline. The sediment disaster defense technology test bed is divided into a new city and an old city, and old city test bed is under construction. The result obtained through the monitoring of the test bed in the new city, sediment disasters such as debris can delay the time to reach the downtown area, and it is possible to secure the golden time, such as evacuation and rescue through the warning system. Also, the maintenance of the test bed application was suggested. Continuous and systematic monitoring is required for securing the reliability of element technology and successful commercialization.

Improving the Endurance Life of Deep Groove Ball Bearings for Automotive Transmission (자동차 변속기용 깊은 홈 볼 베어링의 내구수명 향상)

  • Baek, Hye-Yeon;Pyun, Jung-Min;Lee, Dae-Yong;Park, Tae-Jo
    • Tribology and Lubricants
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    • v.31 no.6
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    • pp.281-286
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    • 2015
  • Automotive transmission systems are assembled with a large number of gears and shafts, and rolling bearings are used to ensure their smooth operation. Gear oil in the gear box contains solid particles such as wear debris from contacting gears and metallic chips. This particle-enriched lubricating oil can cause premature failure of the rolling bearings. Research aimed at improving the service life of these rolling bearings has been confined mainly to design and lubrication of the inner/outer rings and the rolling elements. In this paper, we redesigned the shape of the cage pocket of a deep groove ball bearing to reduce the premature failure due to particle contamination. Test bearings are assembled with this new cage design containing a hole punched in the cage pocket. Endurance tests are carried out using the contaminated lubricating oil with miracle grid as hard particle. The duration and damaged bearing component shapes are compared for two different cages. The B10 life of bearing with new cage is increased by about 66% compared to the conventional cage. This is because the hard particles can be easily discharged through the pocket hole without staying for a long time in the lubrication regions. This greatly decreases abrasive wear and dents on the highly stressed ball bearing surfaces. Therefore, the cage design of this study, containing a pocket hole, can significantly delay the premature failure of rolling bearings and improve the endurance life.

Effects of Lubricant on Fretting Corrosion of Tin-Coated Electric Contacts (주석 도금한 전기 접촉부의 미동마멸 부식에 대한 윤활유의 영향)

  • Kim, Kwang-Su;Oh, Man-Jin;Han, Dong-Woon;Kim, Ho-Kyung
    • Tribology and Lubricants
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    • v.32 no.3
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    • pp.88-94
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    • 2016
  • We conduct a series of fretting corrosion tests on tin-coated electric contact to evaluate the effects of lubricant on fretting corrosion behavior. We perform these tests with a constant contact force at 25℃ 50℃, 75°C, and 100℃. In the tests with a span amplitude of 30 μm, we could not determine the conventional behavior of the first, second, and third stages of the change in electric resistance during fretting corrosion and observed that the contact resistance continuously increases with the cycles. This behavior is due to the fact that the generation of oxides on the tin-coated contact is controlled and stabilized by the presence of lubricant. SEM observations on samples with a span amplitude of 77 μm at all testing temperatures confirm that there is less oxide debris on the fretting damaged surface. Hence, for tin-coated electric connector, the effect of lubrication on the lifetime of the electric contact increases as the fretting span decreases and testing temperature increases, compared to those for connector without lubricant. Especially, for a specimen with a span amplitude of 30 μm at 100℃, the increment in contact lifetime due to lubricant is found to be more than 20 times, compared to that without lubricant.