• Title/Summary/Keyword: Adhesion control

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Study on Adhesion Formation by Artificial Injuries in Rats (쥐에서 인공창상에 의한 유착형성에 관한 연구)

  • Kang Tae-Young;Choi Min-Cheol;Lee Hyo-Jong
    • Journal of Veterinary Clinics
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    • v.9 no.2
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    • pp.483-488
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    • 1992
  • This experiment was carried out to establish the grade of adhesion formation and changes of blood following artificial injuries such as abrasion, incision and electrocautery on colon and uterine horns in rats. 36 rats (abrasion-, incision-, electrocautery-treated groups) had laparotomy and abdominal injuries, twelve rats( control group) had only laparotomy, Ten days fellowing abdominal injuries, the score of adhesion formation and changes of blood were noted 1. Electrocautery-treated group was significant evident in adhesion formation in colon(p<0.01) and electrocautery and incision-treated groups were more evident than abrasion and control group in uterine horns(p<0.01) 2. Changes of erythrocytes number and PCV were tended to decrease during 5 days after operation, but recover normal level 10 days after operation. 3. Changes of leucocytes number were showed to significantly increase in electrocautery and incision-treated groups 5 days after operation. 4. The electrocautery-treated group was showed to significantly decrease in plasma protein and increase in plasma fibrinogen concentration.

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Cellular Adhesion and Growth on the Vertically Aligned Silicon Nanowire Arrays

  • Yun, Seo-Yeong;Park, Lee-Seul;Lee, Jin-Seok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.266.2-266.2
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    • 2013
  • According to advanced nanotechnology, the nanostructured materials with various kinds and shape are synthesized easily or produced by process. Recently, researches about interaction between the nanostructured materials and biological system have been progressed actively. The surface topography may influence cellular responses, for example cell adhesion, cell morphology. In this work, we synthesized vertically aligned silicon nanowires (SiNWs) on the Au-covered Si(111) wafer by chemical vapor deposition (CVD) method. We accomplished to control of the SiNWs diameter by regulating thickness of Au film such as 1 nm and 10 nm. These substrates did not isolate cells and just provided surface topography for cell culture. Human Embryonic Kidney 293T cells (HEK 293T cells) were cultured on these substrates for 2 days. We studied the nanotopographical effects on cell morphology, adhesion, and growth which are evaluated on each SiNWs substrate comparing bare glass as control.

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Variable Parameter Sliding Controller Design for Vehicle Brake with Wheel Slip

  • Liang, Hong;Chong, Kil-To
    • Journal of Mechanical Science and Technology
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    • v.20 no.11
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    • pp.1801-1812
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    • 2006
  • In this paper, a 4-wheel vehicle model including the effects of tire slip was considered, along with variable parameter sliding control, pushrod force as the end control parameter, and an antilock sliding control, in order to improve the performance of the vehicle longitudinal response. The variable sliding parameter is made to be proportional to the square root of the pressure derivative at the wheel, in order to compensate for large pressure changes in the brake cylinder. A typical tire force-relative slip curve for dry road conditions was used to generate an analytical tire force-relative slip function, and an antilock sliding control process based on the analytical tire force-relative slip function was used. A retrofitted brake system, with the pushrod force as the end control parameter, was employed, and an average decay function was used to suppress the simulation oscillations. Simulation results indicate that the velocity and spacing errors were slightly larger than the results that without considering wheel slip effect, the spacing errors of the lead and follower were insensitive to the adhesion coefficient up to the critical wheel slip value, and the limit for the antilock control on non-constant adhesion road condition was determined by the minimum of the equivalent adhesion coefficient.

Sodium Carboxymethylcellulose and Hyaluronic Acid on Prevention of Intra-abdominal Adhesion in Rats (Rat에서 Sodium Carboxymethylcellulose와 Hyaluronic acid의 복강 내 유착 예방)

  • 한태성;이주명;윤영민;강태영;신태균;강윤호;김남중;김희석;이경갑
    • Journal of Veterinary Clinics
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    • v.20 no.3
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    • pp.323-327
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    • 2003
  • This study has been conducted to compare the efficacy of sodium carboxymethylcellulose (SCMC) and hyaluronic acid (HA) on prevention of adhesion after artificial wound was induced in intestine. 1 % SCMC and 0.3% HA solution and saline solution were respectively administered to abdominal cavity. Each of the three groups consists of 11 rats. The abdominal cavity of each rat was coated with 2 ml of the allocated solution just after the abdomen was cut open, and it was coated with each solution of 1 ml before abrasion were caused on the cecum, the ascending colon and the transverse colon. Then, an additional 1 ml solution was injected before the abdomen was closed. On day 14 after the operation, each adhesion formation was evaluated at the score of 0-4. The HA group and SCMC group showed significantly lower adhesion scores than control group in all regions(P< 0.05). The adhesion scores of ascending colon, transverse colon and no abrasion region of the viscera showed little difference between HA group and SCMC group(P< 0.05), but the effect of adhesion reduction showed higher tendency in the HA group than the SCMC. The adhesion score of the cecum was significantly lower in HA group than SCMC group(P< 0.05). In conclusion, the SCMC solution and HA solution were effective on prevention of abdominal adhesion resulting from the celiotomy. Among of them, the HA solution could be more effective on prevention of adhesion than SCMC solution.

Electrical Effects of the Adhesion Layer Using the VDP Process on Dielectric

  • Lee, Dong-Hyun;Pyo, Sang-Woo;Hyung, Gun Woo;Kim, Young-Kwan
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1313-1316
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    • 2005
  • In the present paper, it was investigated that adhesion layer on gate insulator could affect the electrical characteristics for the organic thin film transistors (OTFTs). The polyimide (PI) as organic adhesion layer was fabricated by using the vapor deposition polymerization (VDP) processing . It was found that electrical characteristics improved comparing OTFTs using adhesion layer to another. We researched adhesion layer as a function of thickness. For inverted-staggered top contact structure, field effect mobility, threshold voltage, and on-off current ratio of OTFTs using adhesion layer of PI 15 nm thickness on the gate insulator with a thickness of 0.2 ${\mu}m$ were about 0.5 $cm^2/Vs$, -0.8 V, and $10^6$, respectively.

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Correlation Study on Tire Belt Adhesion Properties and Durability Performance (타이어의 벨트 부착력과 내구성능 간의 상관성 연구)

  • Hong Seungjun;Lee Hoguen
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.29 no.6 s.237
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    • pp.804-808
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    • 2005
  • A pneumatic tire is made up of many flexible filaments of high modulus cord of natural textile, synthetic polymer, glass fiber, or fine hard drawn steel embedded in and bonded to a matrix of low modulus polymetric material. Adhesion property of these materials is very important in tire durability safety because belt-leaving-belt tread separation reduces the ability of a driver to control a vehicle, whether or not the separation is accompanied by a loss of air. In this study adhesion test of carcass-belt-tread is conducted on material properties of 5 PCR tire model, which are on sale in domestic market and analyzed adhesion properties. For those tire models FMVSS 109 indoor high speed durability test is conducted to analyze the correlation between adhesion force and high speed performance of tires and found the correlation between the two test results.

Activated Rap1A Induces Osteoblastic Differentiation and Cell Adhesion

  • Kim, Hyeseon;Jeon, Taeck J.
    • Journal of Integrative Natural Science
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    • v.9 no.3
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    • pp.171-176
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    • 2016
  • Rap1 is a key regulator of cell adhesion and migration. Although increasing evidence indicates that the Rap1 signaling pathway is involved in the process of bone remodeling, the mechanism by which Rap1 regulates osteoblastic differentiation and cell adhesion remains unknown. Here, we investigated the morphological characteristics and osteoblastic differentiation of cells expressing constitutively activated form of Rap1A (Rap1ACA) or Rap1 GTPase activating protein Rap1GAP and found that activated Rap1 induces osteoblastic differentiation and cell adhesion as well as cell spreading. When osteoblastic differentiation was induced, Rap1ACA cells showed considerably higher levels of calcium deposits than the wild-type and Rap1GAP-overexpressing cells did. Rap1ACA cells showed increased spreading and size, as well as strong cell adhesion and significantly decreased growth rates. F-actin staining using phalloidin revealed several thin thread-like filopodia around the protrusions in Rap1ACA cells, which possibly contribute to the increased cell adhesion.

Experimental Studies for the Prevention of Pericardial Adhesion with Urokinase and Dextran 40 (Urokinase 와 Dextran 40 을 이용한 심막유착 방지에 관한 실험적 연구)

  • Kim, Byeong-Ju;Kim, Se-Hwa;Lee, Hong-Gyun
    • Journal of Chest Surgery
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    • v.19 no.2
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    • pp.225-231
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    • 1986
  • Pericardial adhesions following open heart surgery pose a special problems, increasing the risk of cardiac reoperation because of the danger of damaging the heart, coronary artery and veins, or grafts and also the fibrous tissue may obliterate the pericardial space and eventually constrict the heart. This study was undertaken to evaluate the effect of intrapericardial urokinase and dextran 40 on the formation of pericardial adhesions in an animal model. latrogenic traumas on the pericardium were surgically induced in 30 rabbits, simulating injuries possible during actual surgery. In all rabbits, blood [1 ml] was obtained from an ear vessel and injected into the pericardium. Control group of ten rabbits did not receive any further medication, urokinase group of ten received 15, 000-20, 000 IU of urokinase, and remained ten received 1 ml of 10% dextran 40. All rabbits were sacrificed at 4 weeks. At autopsy, the development of adhesions were graded as none [Grade I], minimal [Grade II], moderate [Grade III], and severe [Grade IV]. Histological studies of the parietal pericardium and epicardium were performed. The results were as follows: 1. Group 1[Control group] showed minimal adhesion in 40%, moderate in 50%, and severe in 10% of the group. Sharp dissections were necessary in 60% of adhesions. 2. Group II [Dextran group] showed no adhesions in 20%, minimal in 60%, and moderate in 20% of the group. 3. Group III [Urokinase group] showed no adhesions in 40%, minimal in 40%, and moderate in 20% of the group. Considering in this group, the adhesion activity was significantly suppressed [60% adhesions] compared to the control group [100% adhesions] [P < 0.05]. 4. Histological findings revealed mild serosal fibrosis in none adherent group, loose fibrous connections between two layers of pericardium in minimal adhesion group, tight fibrous connections in moderate adhesion group, and marked fibrous thickening and close attachment of two surfaces were noted in severe adhesion group. These data have revealed the decreased incidence of pericardial adhesions with urokinase and dextran 40.

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Long-Term Evaluation of the Lip and Nose in Bilateral Complete Cleft Lip Patients following Lip Adhesion and Secondary Nose Correction

  • Kim, Ryuck Seong;Seo, Hyung Joon;Park, Min Suk;Bae, Yong Chan
    • Archives of Plastic Surgery
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    • v.49 no.4
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    • pp.510-516
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    • 2022
  • Background Surgical correction of bilateral cleft lip deformities remains one of the most challenging areas in facial plastic surgery. Many surgical techniques and conservative devices have been offered for the early management of bilateral cleft lip in infants. The purpose of this study was to evaluate the effect of lip adhesion on the lip and nose of patients with bilateral cleft lip. Methods A retrospective review of 13 patients with bilateral cleft lip was performed and compared with age-matched noncleft children. Patients underwent lip adhesion at a mean age of 2.8 months, and cheiloplasty at 6.6 months of age using a modification the Mulliken method. Secondary rhinoplasty was performed at the age of 6 in 13 patients. The surgical results were analyzed using photographic records obtained at the age of 1 and 7 years. Twelve length measurements and one angle measurement were obtained. Results All measurements were not statistically different from those of the noncleft age-matched control group at the age of 1. At 7 years of age, upper lip height and vermilion mucosal height were shorter (p < 0.05) than in the control group. Nasal tip protrusion and the nasolabial angle were greater (p < 0.05) than in the control group. Conclusion Lip adhesion followed by secondary rhinoplasty resulted in an acceptable lip and nasal appearance. Although nasoalveolar molding is now widely used, lip adhesion can be an appropriate alternative if an orthodontist is not available due to geographical or economic constraints.