• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2004.11a
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• pp.83-89
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• 2004

In this paper, molecular dynamics simulations are performed to analyze the adhesion between a diamond mould and a copper substrate in diamond nanoimprint lithography. The diamond nanoimprint lithography process is simplified as punch-type nanoindentation. The copper substrates are assumed to monocrystalline and defect free and consist of $22500\~80000$ atoms depending on their dimension. The diamond moulds consist of 916 or 2414 atoms, which is assumed to be rigid. The consistent results lot the maximum normal force and the adhesion force are obtained regardless of the size of substrates and the adhesion hysteresis is shown in all cases. It is found that the friction acting on the sidewalls of the mould affects the adhesion significantly when the mould is released from the substrate.

• Proceedings of the KAIS Fall Conference
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• 2008.05a
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• pp.309-312
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• 2008

We have prepared the silicone sealant using non silicone oil without silicone oil for solvent and using adhesion promotor against various substrate. We are replaced the silicone oil by the mineral oil and the normal adhesion promotor by mixed adhesion promotor at the multi purpose silicone sealant.

• Tribology and Lubricants
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• v.18 no.4
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• pp.267-272
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• 2002

Nano adhesion between SPM(scanning probe microscope) tips and DDPO$_4$(octadecylphosphoric acid ester.) and ODPO$_4$(octadecylphosphoric acid ester) SAM(self-assembled monolayer.) was experimentally studied. Tests were performed to measure the nano adhesion and friction in both AFM(atomic force microscope) and LFM(lateral force microscope) modes with the applied normal load. DDPO$_4$ and ODPO$_4$ SAM were formed on Ti and TiOx surfaces. Ti and TiOx were coated on the Si wafer by ion sputtering. Adhesion and friction of DDPO$_4$ and ODPO$_4$ SAM surfaces were compared with those of OTS(octadecyltrichlorosilane) SAM and DLC surfaces. DDPO$_4$ and ODPO$_4$ SAM converted the Ti and TiOx surfaces to be hydrophobic. When the surface was hydrophobic, the adhesion and friction forces were found lower than those of bare surfaces. Work of adhesion was also discussed to explain how the surface was converted into hydrophobic Results also showed that tribological characteristics of DDPO$_4$ and ODPO$_4$ SAM had good properties in the adhesion, friction, wetting angle and work of adhesion. DDPO$_4$ and ODPO$_4$ SAM could be one of the candidates for the bio-MEMS elements.

• IMMUNE NETWORK
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• v.13 no.5
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• pp.199-204
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• 2013

Syntenin is an adaptor molecule containing 2 PDZ domains which mediate molecular interactions with diverse integral or cytoplasmic proteins. Most of the results on the biological function of syntenin were obtained from studies with malignant cells, necessitating exploration into the role of syntenin in normal cells. To understand its role in normal cells, we investigated expression and function of syntenin in human lymphoid tissue and cells in situ and in vitro. Syntenin expression was denser in the germinal center than in the extrafollicular area. Inside the germinal center, syntenin expression was obvious in follicular dendritic cells (FDCs). Flow cytometric analysis with isolated cells confirmed a weak expression of syntenin in T and B cells and a strong expression in FDCs. In FDC-like cells, HK cells, most syntenin proteins were found in the cytoplasm compared to weak expression in the nucleus. To study the function of syntenin in FDC, we examined its role in the focal adhesion of HK cells by depleting syntenin by siRNA technology. Knockdown of syntenin markedly impaired focal adhesion kinase phosphorylation in HK cells. These results suggest that syntenin may play an important role in normal physiology as well as in cancer pathology.

• Journal of Veterinary Clinics
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• v.18 no.2
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• pp.124-132
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• 2001

The purpose of this study is to know whether single layer continuous connell suture is an acceptable alternative to simple interrupted approximating suture for end-to-end intestinal anastomosis in dogs. Fourteen mixed-breed dogs weighing 2 to 5 kg were allotted to group treated with simple interrupted approximating suture (Group I) and group treated with single layer continuous Connell suture (Group II), each of 7 dogs. All dogs in each suture pattern were compared with time for total operation ad suture elapsed for intestines to anastomose, clinical signs, changing of pre-and postoperative luminal size, status of feces, adhesion at anastomotic site for 14 days after operation. Time for total operation and suture time for intestinal anastomosis were none significant between Group I and Group II, although those in Group II was about 3 minutes shorter than those in Group I, respectively. Group I spent average 47.08${\pm}$11.10 minutes on total operation, 20.97${\pm}$5.54 minutes on suture time for intestinal anastomosis and Group II spent average 44.74${\pm}$7.77 minutes, 17.73${\pm}$3.05 minutes, respectively. All dogs were no special differences in vitality, vomiting, appetite between Group I and Group II for 14 days after operation. All dogs, except one dog in Group I, had showed normal vitality and appetite since 6~8 days after operation. Initial return of fecal passage showed in all dogs before 6 days after operation and thereafter most dogs showed normal feces. According to results, it was thought that all dogs with normal vitality and appetite before 8 days had showed good prognosis. There were no changes of intestinal luminal size in 2 dogs performed Group In and one dog performed Group II between at operation and 14 days after operation. Narrowing rate of intestinal lumen in Group I was average 9.3% of the normal diameter, whereas in Group II, 9.5% of normal diameter. In complications after operation, only one dog in Group I showed intestinal intussusception but the others didn't. Length of adhesion was measured between intestinal anastomotic site and omental graft. Length of adhesion in dogs performed Group II was mostly shorter than that of Group I. Adhesion with proximate intestines occurred in five dogs, which consisted of 3 dogs performed Group I and 2 dogs performed Group II. Concurrently, they had a great length of adhesion between anastomotic site and omental graft. There were no great differences between Group I and Group II about speed of operation, clinical signs, complications such as leakage and stricture. And all dogs performed intestinal anastomosis showed good clinical condition and prognosis. In conclusion, Single layer continuous Connell suture can safely perform an intestinal anastomosis and be an alternative of simple interrupted approximating suture in aspect of speed clinically.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.282-283
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• 2014

An active study on UHPC, which has been recently used in high-rise building and bridges, is in progress. However, research on adhesion strength of normal concrete and UHPC is required to be studied due to the lack of information. In this study, experimental research progress for adhesion strength (shear strength of adhesive surface) evaluation of Bi-compressive strength concretes (UHPC, Normal concrete) is proceeded. First, specimens using glue are produced and surface treatment methods of concrete bonded section are considered. Second, Direct Shear test is applied on concrete bonded section of UHPC (80~180MPa) and Normal Concrete (NC). As a result of this study, it is confirmed that bond strength is deteriorated as the difference of intensity ration of NC and UHPC increases.

• Tuberculosis and Respiratory Diseases
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• v.40 no.2
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• pp.185-191
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• 1993

Background: Intercellular adhesion molecule-1(ICAM-1) is a 90 kD surface glycoprotein, associated with ${\alpha}_L{\beta}_2$ and ${\alpha}_M{\beta}_2$ subunit of integrins, that serve as cell-cell and cell-substratum adhesion molecules and help regulate cellular morphology, differentiation, and proliferation. The adhesion molecules likely play important roles in maintaining the normal structure and function of the lung. ICAM-1 system among many cell adhesion molecules is importantly issuing in the pathogenesis of idiopathic pulmonary fibrosis. Methods : By using $IgG_1$ monoclonal antibody for ICAM-1, we investigated immunohistochemically the expression of ICAM-1 in the formalin-fixed, paraffin-embedded tissue sections of the 3 normal cases and 6 pieces of tissues taken 3 cases with idiopathic pulmonary fibrosis. Results : In the 3 normal cases, the expressions of ICAM-1 were not discernible. Up-regulation of the ICAM-1 expression was showed in the interstitial fibroblast cells of alveolar septa in 5 pieces and proliferated alveolar pneumocytes in 1 piece among 6 pieces of tissues taken 3 cases with idiopathic pulmonary fibrosis. Conclusion : It was concluded from these findings that up-regulation of the ICAM-1 expression may be related to pathogenesis of idiopathic pulmonary fibrosis.

• BMB Reports
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• v.50 no.8
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• pp.429-434
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• 2017

Endometriosis is the abnormal growth of endometrial cells outside the uterus, causing pelvic pain and infertility. Furthermore, adhesion of endometrial tissue fragments to pelvic mesothelium is required for the initial step of endometriosis formation outside uterus. $TGF-{\beta}1$ and adhesion molecules importantly function for adhesion of endometrial tissue fragments to mesothelium outside uterus. However, the function of $TGF-{\beta}1$ on the regulation of adhesion molecule expression for adhesion of endometrial tissue fragments to mesothelium has not been fully elucidated. Interestingly, transforming growth factor ${\beta}1$ ($TGF-{\beta}1$) expression was higher in endometriotic epithelial cells than in normal endometrial cells. The adhesion efficiency of endometriotic epithelial cells to mesothelial cells was also higher than that of normal endometrial cells. Moreover, $TGF-{\beta}1$ directly induced the adhesion of endometrial cells to mesothelial cells through the regulation of integrin of ${\alpha}V$, ${\alpha}6$, ${\beta}1$, and ${\beta}4$ via the activation of the $TGF-{\beta}1/TGF-{\beta}RI/Smad2$ signaling pathway. Conversely, the adhesion of $TGF-{\beta}1-stimulated$ endometrial cells to mesothelial cells was clearly reduced following treatment with neutralizing antibodies against specific $TGF-{\beta}1-mediated$ integrins ${\alpha}V$, ${\beta}1$, and ${\beta}4$ on the endometrial cell membrane. Taken together, these results suggest that $TGF-{\beta}1$ may act to promote the initiation of endometriosis by enhancing integrin-mediated cell-cell adhesion.

• Journal of Veterinary Clinics
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• v.13 no.2
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• pp.144-148
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• 1996

The effectiveness of sodium carboxymethylcellulose (SCMC) and deztran in the prevention of adhesion formation on the uterus and embryo collection in rabbits was elucidated. Following induction of adhesion on uterus and uterine horns by abrasion and retrograde flushing of embryos in gonadotropins primed rabbits, the solutions of saline (for control), 1% SCMC, 10% dextran and a synthetic solution of 1% SCNC and 10% dextran in saline were infused in the abdominal cavity at the dose of 5 ml/kg of body weight. The average percentage of adhesion was 11.1, 28.6, 41.7 and 73.3% in the rabbits infused with the synthetic, 1% SCMC, 10% dextran and saline solutions, respectively. The synthetic solution was more effective than other solutions in the rabbits. The average number and recovery rate of embryos were significantly (P<0.01) higher in the synthetic solution group than 1% SCMC, 10% dextran or saline solution groups. Among the collected embryos in the groups, the distribution of the normal embryos was higher in the synthetic solution group (99%) and the 10% dextran solution group (95.7%) than the 1% SCMC solution group (78.4%) and saline (66.2%). Theretore, a synthetic solution which is combined with 1% SCMC and 10% deztran in saline can be effectively used for the prevention of adhesion formation after uterine surgery and embryo collection.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.8
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• pp.1698-1708
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• 2002

The main topic covered in this paper is that of the impact process, that is, where two bodies come into contact and rebound or stick together. This paper presents how to determine the rebound velocities of a microparticle that approaches a surface with arbitrary initial velocities and relate the impact process to the physical properties of the materials and to the adhesion force. Actual adhesion forces demonstrate a significant amount of energy dissipation in the form of hysteresis, and act generally in a normal to the contact surfaces. Microparticles must also contend with forces tangent to the contact surfaces, namely Coulomb dry friction. The developed model has an algebraic form based on the principle of impulse and momentum and hypothesis of energy dissipation. Finally, several analyses are carried out in order to estimate impact parameters and the developed analytical model is validated using experimental results.