• Journal of Periodontal and Implant Science
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• v.28 no.2
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• pp.249-264
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• 1998

The present study evaluates the effects of calcium sulfate and DFDB on alveolar bone regeneration and cementum formation and connective tissue adhesion in intrabony angulated 1 wall defects of dogs. Four millimeter-deep angulated one-wall intrabony defects were surgically created in the mesial & distal aspects of premolars and with flap operaion alone(control group), with calcium sulfate(experimental group 1), with composit graft of 50% calcium sulfate and 50% DFDB(experimental group 2), with DFDB alone(experimental group 3). Histologic analysis following 8 weeks of healing revealed the following results: 1. The lengths of connective tissue adhesion was $1.05{\pm}0.48mm$ in the control, $1.30{\pm}0.67mm$ in the test group I, $0.97{\pm}0.22mm$ in the test group II and $0.93{\pm}0.15mm$ in the test group III. There was no statistical significance between control and all experimental groups. 2. Changes in alveolar bone level was $0.97{\pm}0.27mm$ in the control group, $1.45{\pm}0.42mm$ in the test group I, $2.00{\pm}0.33mm$ in the test group II, $1.88{\pm}0.34mm$ in the test group III. There was no statistically significant difference between control and experimental group I. There was a statistically significant difference between the control and experimental group II,III.(p<0.05). There was no statistically significant difference between all experimental group. 3. Cementum formation was $1.13{\pm}0.17mm$ in the control, $1.78{\pm}0.31mm$ in the test group I, $2.17{\pm}0.38mm$ in the test group II, $2.15{\pm}0.47mm$ in the test group III with statistically significant differences between control group and all experimental group(P<0.05). There was no statistically significant differences between all experimental group. These results suggest that the use of composit graft of 50% calcium sulfate and 50% DFDB and DFDB alone in angulated 1 wall intrabony defects has little effects on connective tissue adhesion, but has significant effects on new bone and new cementum formations.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.05a
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• pp.173-178
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• 2005

The tile construction methods for existing have been used materials within limit which adhesion by wet method in masonry wall and concrete structure. These existing adhesive tech can caused many problems in construction of large and reform tile, after that it can be happened loose scale, peel off, falling off tile by heat and vibration or impact. In according to, this study is to test tile for bond stability, adhesive property by impact, vibration. low property by heat and then, we have the results as below; (1) The tile adhesive stability can be effected as adhesive area between bond agent and tile, adhesive area can more wide and press enough to ensure property. (2) Existing adhesive strength and standard relative tile construction is limited to adjust performance tile on the concrete and masonry wall. In summary, It is necessary to establish standard of performance and test method to ensure tile adhesive salability in dry wall.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.4
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• pp.359-367
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• 2013

With recent growth of the economy and development of construction technology, the increase of high-rise buildings is appearing rapidly in urban areas. For this reason, the interest in building maintenance has also been increasing. However, it has many safety problems because it is difficult for the workers to access the exterior wall of building. Therefore, the maintenance system of high-rise building stands out as being important issues to be developed, so that a variety of robot systems have been developed to accomplish the building-wall maintenance works. In this paper, the maintenance robots are classified in painting, inspecting, cleaning systems according to the maintenance works. Then, their locomotion and adhesion mechanisms are analyzed including their applicability to the real maintenance works. This study can be used to develop maintenance robotic system that is more efficient and stable than existing ones.

• Journal of the Korean GEO-environmental Society
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• v.9 no.5
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• pp.71-81
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• 2008

Active earth pressure formula, which can consider the effects of ground surface inclination, inclination of inside retaining wall face, wall friction, line load, uniform load, soil cohesion and adhesion, was derived based on the force equilibrium principle. In order to verify the accuracy of this proposed formula, the calculated active earth pressures by the proposed formula were compared with those of graphical solutions. Also, the active earth pressures determined by the proposed formula were compared with those by Coulomb's, Rankine's and Mazindrani's solution under specific conditions. The results matched quite well not only with the graphical solutions but also with those by three other methods. Also, the trend of active earth pressures by the proposed formula were corresponded with results of experimental study by Fang, et al. It can be concluded that this generalized formula not only can overcome the limitations of Rankine's, Coulomb's and Mazindrani's active earth pressure formula but also can consider the external loading conditions.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.2
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• pp.178-184
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• 2012

This paper presents a transformable track mechanism for wall climbing robots. The proposed mechanism allows a wall climbing robot to go over obstacles by transforming the track shape, and also increases contact area between track and wall surface for safe attachment. The track mechanism is realized using a timing belt track with one driving actuator. The inner frame of the track consists of serially connected 5R-joints and 1P-joint, and all joints of the inner frame are passively operated by springs, so the mechanism does not require any actuators and complex control algorithms to change its shape. Static analysis is carried out to determine design parameters which enable $90^{\circ}$ wall-to-wall transition and driving over projected obstacles on wall surfaces. A Prototype is manufactured using the transformable track on which polymer magnets are installed for adhesion force. The size of the prototype is $628mm{\times}200mm{\times}150mm$ ($Length{\times}Width{\times}Height$) and weight is 4kgf. Experiments are performed to verify its climbing capability focusing on $90^{\circ}$ wall to wall transition and driving over projected obstacle.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.2
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• pp.133-137
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• 2013

Vascular cell adhesion molecule 1 (VCAM-1), intercellular adhesion molecule 1 (ICAM-1), P- and E-selectin play a pivotal role for initiation of atherosclerosis. Ginsenoside, a class of steroid glycosides, is abundant in Panax ginseng root, which has been used for prevention of illness in Korea. In this study, we investigated the mechanism(s) by which ginsenoside Rg2 may inhibit VCAM-1 and ICAM-1 expressions stimulated with lipopolysaccharide (LPS) in human umbilical vein endothelial cell (HUVEC). LPS increased VCAM-1 and ICAM-1 expression. Ginsenoside Rg2 prevented LPS-mediated increase of VCAM-1 and ICAM-1 expression. On the other hand, JSH, a nuclear factor kappa B (NF-${\kappa}B$) inhibitor, reduced both VCAM-1 and ICAM-1 expression stimulated with LPS. SB202190, inhibitor of p38 mitogen-activated protein kinase (p38 MAPK), and wortmannin, phosphatidylinositol 3-kinase (PI3-kinase) inhibitor, reduced LPS-mediated VCAM-1 but not ICAM-1 expression. PD98059, inhibitor of mitogen-activated protein kinase kinase/extracellular signal-regulated kinase (MEK/ERK) did not affect VCAM-1 and ICAM-1 expression stimulated with LPS. SP600125, inhibitor of c-Jun N-terminal kinase (JNK), reduced LPS-mediated ICAM-1 but not VCAM-1 expression. LPS reduced IkappaB${\alpha}$ ($I{\kappa}B{\alpha}$) expression, in a time-dependent manner within 1 hr. Ginsenoside Rg2 prevented the decrease of $I{\kappa}B{\alpha}$ expression stimulated with LPS. Moreover, ginsenoside Rg2 reduced LPS-mediated THP-1 monocyte adhesion to HUVEC, in a concentration-dependent manner. These data provide a novel mechanism where the ginsenoside Rg2 may provide direct vascular benefits with inhibition of leukocyte adhesion into vascular wall thereby providing protection against vascular inflammatory disease.

• Composites Research
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• v.35 no.2
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• pp.80-85
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• 2022

This work presents an experiment study to evaluate the nanoparticle adhesion and surface hydrophobicity characteristics of Teflon-polyurethane top coat depending on the number of multi-wall carbon nanotube (MWCNT) coatings, which is a carbon-based hydrophobic particle. In order to measure the adhesion between the nanoparticles and the top coat, adhesion pull-off test was performed with different MWCNT oxidation times. Static contact angle and roughness measurements were carried out to characterize the surface hydrophobic behavior. Through the roughness evaluation, it was confirmed that the carbon nanotubes were wetted in the Teflon-polyurethane top coat, and the degree carbon nanotube wetting was confirmed through a USB-microscope. As a result, it was found that the larger the degree of wetting, the better the adhesion. From the experimental results, as the hydrophobicity of Teflon-polyurethane increased, the adhesive propertydecreased with the number of coatings. It was possible to improve the adhesive force and determine the number of coatings of carbon nanotubes with optimized hydrophobicity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.1134-1141
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• 2002

Adhesion of leukocytes to the activated vascular endothelium and their subsequent recruitment/migration into the artery wall are key features in the pathogenesis of atherosclerosis and inflammatory diseases. These features have been mediated by cell adhesion molecules including vascular cell adhesion molecule-1 (VCAM-1) and in tracellular cell adhesion molecule-1 (ICAM-1). This study examined whether flavonoids inhibit the pro-inflammatory cytokine TNF-$\alpha$-induced monocyte adhesion via a modulation of the protein expression of VCAM-1 and ICAM-1 of human umbilical vein endothelial cells (HUVECs). TNF-$\alpha$ markedly increased the adhesion of THP-1 monocytes to endothelial cells and induced the expression of VCAM-1, ICAM-1 and E-selectin proteins in HUVECs. Micromolar concentrations of the flavones luteolin and apigenin and the flavonol quercetin near completely blocked the monocyte adhesion to the activated endothelial cells and the induction of these adhesion molecules. However, equimicromolar catechins of (-)epigallocatechin gallate and (+)catechin, the flavonol myr- icetin and the flavanones of naringin and hesperidin had no effect on TNF-$\alpha$-activated monocyte adhesion. (-)Epigallocatechin gallate, (+) catechin, and naringin did not attenuate the TNF-$\alpha$ induction of these adhesion molecules. Furthermore, culture with luteolin and apigenin strongly blocked the expression of TNF-$\alpha$-induced VCAM-1 mRNA and modestly attenuated ICAM-1 mRNA. Quercetin modestly decreased the TNF-$\alpha$-activated VCAM-1 and ICAM-1 mRNAs. These results demonstrate that flavonoids classified as flavones and flavonols may inhibit monocyte adhesion to the TNF-$\alpha$-activated endothelium, most likely due to a blockade of expression of functional adhesion molecules down-regulated at the transcriptional level, indicating a definite linkage between the chemical structure of flavonoids and the expression of cell adhesion molecules. Furthermore, the antiathero-genic feature of flavonoids appears to be independent of their antioxidant activity.

• Journal of the Korean Wood Science and Technology
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• v.32 no.3
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• pp.71-78
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• 2004

The purpose of this study was to investigate the water absorption and thickness swelling of biocomposites at room temperature. These properties of bio-composites mainly depend on the ability of the agro-flour to absorb water through hydrogen bonding between water and the hydroxyl groups of the holocellulose and lignin in the cell wall. As the content of agro-flour increased, the water absorption and thickness swelling of the bio-composites increased. The effects of agro-flour content and rice husk flour (RHF) particle size on the water absorption and thickness swelling of the bio-composites were evaluated. In general, wood-based materials showed significantly higher water absorption and thickness swelling than the bio-composites. This might be attributed to the ability of the polybutylene succinate (PBS) hydrophobic polymer to prohibit the water absorption and thickness swelling of the bio-composites, Therefore, the use of agro-flour filled PBS bio-composites, which exhibit improved dimensional stability in comparison with wood-based materials, is recommended.

• Korean Journal of Veterinary Research
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• v.5 no.1
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• pp.27-30
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• 1965

In a cattle which had died of extreme emaciation caused by cachexic condition, a huge cyst of $45{\times}35{\times}20$cm, in size was found at the rumen. The cyst having with the narrow stalk which ended in blind sac attached firmly to the rumen by fibrinous or fibrous adhesion and, contained the lightly yellowish, clear exudative fluid of about 20 l, in volume. Grossly, the thickness of the cyst wall was 10~14mm, and its inner portion of the half was very rigid and colored with milky white in contrast with soft and edematous outer portion of the half. Microscopically the inner portion of the cyst wall was consisted of scarred fibrous tissue and possessed at its inner margin a little amount of the muscle fibers which had degenerated passably. These were confirmed as the muscle fibers in specific staining property by Van-Gieson's and Mallory-Azan stain. On regarding to above findings of gross and microscopic pictures, it was considered to be a pseudo-diverticulous cyst composed of the serosa and the muscle layer deriving from the wall of the rumen. And it was suggested that the cyst had been growing up to big size by storage of the plenty exudate arisen from its wall and was separated from the rumen at the end of its stalk.