• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.7-8
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• 2014

Latex-modified concrete using ready mix concrete (R-LMC) was developed for application of building construction project (specifically, the rooftop of a parking garage unable to use heavy equipments for bridge deck overlay) due to three major outstanding properties of R-LMC; bond strength, resistance of cracks at early age, and resistance of freezing and thawing. However, R-LMC at the placement stage is required to be sufficiently cured because R-LMC is very sensitive to rate of evaporation of surface moisture. This study focused on effects of different curing methods and climate condition on cracks on the surface of hardened R-LMC considering the chart of rate of evaporation of surface moisture from concrete provided by American Concrete Institute in manual for placement of latex modified concrete.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.9-10
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• 2014

Cracks on the surface of latex-modified concrete using ready mix concrete (R-LMC) are attributable to its sensitivity to air temperature, relative humidity and wind velocity. Insufficient curing under the windy condition causes plastic shrinkage cracks. The cracked areas should be replaced to prevent development of larger cracks. This paper investigated how the vibration resulted from crushing concrete for replacement of the partial cracked area affects bond strength of R-LMC at early age. To analyze bond strength of R-LMC, the commercial Finite Element (FE) program, ABAQUS Standard/Implicit version 6.12 was used, and bond strength was tested by ASTM C1583-04. The real vibration was applied to this FE model using an acceleration measurement equipment.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.11a
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• pp.175-178
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• 2009

This study is thing for construction properties that protect about damage of waterproofing course that is problem in asphalt pavement and latex modification concrete pavement. It is thing about new method of construction and develop protecting material of waterproofing. Did performance test item first at, as a result, drew by suitable thing in all KS items, This is considered to have more effective spot construction work because if means that have stability by material as well as method construction.

• YAKHAK HOEJI
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• v.35 no.3
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• pp.165-173
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• 1991

Effects of eight flavonoids and their related compounds on leukocytes migration, superoxide anion production and lipid peroxidation in the phagocytosis of latex beads or E. coli by guinea pig peritoneal exudate cells were studied in vitro. It shows that most of flavonoids generally inhibited the leukocytes migration and production of superoxide anion and malonedialdehydes. Their inhibitory activities in the phagocytosis of latex beads had more active than that of E. coli. Quercetin has the most inhibitory activity in leukocytes migration and production of superoxide anion and lipid peroxides at the concentration of 1, 2 and 10 $\mu{M}$. Catechin and rutin at the concentration of 2 and 10 $\mu{M}$ inhibited significantly the production of superoxide anion and lipid peroxides. Flavone, catechin, naringin and rutin at the concentration of 2 and 10 $\mu{M}$ inhibited significantly the leukocytes migration.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.445-448
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• 2004

Recently, bridge deck overlay with latex modified concrete is widely applied in domestic. the capacity of bridge deck overlay depends on bond state on the surface. factors that have an effect on bond state are clean condition on the surface, absence of surface microcracking, absence of laitance, overlay curing. In this study, it is researched that characteristic of bond strength according to moisture condition on the surface and the removal method of concrete. As a result, it shows high bond strength in dry condition when w/c is $31\%$ and in moisture condition when w/c is $38\%$ respectively. characteristic of bond strength according to the removal method of concrete shows high bond strength when using water-jets rather than jackhammers.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.841-844
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• 2006

Recently, tunnels being constructed in korea with the increased construction of highways, high-speed railways and hydro structure. shotcrete and spray is one of the major processes in that construction. So general Shotcrete and spray has many problems on strength property, environmental pollution and human body noxiousness as the use of accelerater. However, In this paper using HES-LMS(High Early Strength Latex Modified Spray) without accelerater can solve problems which are mentioned above. problems that the hish early cement has can be solved by modifying material with latex. Therefore HES-LMS mortar is Classify by High performance and High ability. Analysis according to the variables such as W/C, Latex content and sand content is conducted. Studied about mechanical characteristic of material such as each parameter characteristic, and rebound characteristic is completed.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.265-268
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• 2004

Plastic shrinkage cracking is a major concern for concrete, especially for flat structures as highway pavement, bridge deck slabs, and bridge deck pavement. LMC(Latex Modified Concrete) be used mainly for bridge deck overlays, so occurrence possibility of plastic shrinkage cracking is very high. But LMC is form a close-packed layer of polymer particles in very early time from the time of adds the latex and water. So plastic shrinkage cracking compare with normal concrete is not occur at final setting time. Results indicates that LMC is advantage to prevent occurrence of plastic shrinkage crack and it's possible co construction for bridge deck overlay effectively.

• Tuberculosis and Respiratory Diseases
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• v.59 no.6
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• pp.651-655
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• 2005

Background : Diagnosing a pulmonary embolism is difficult because its presenting symptoms are nonspecific and there are limitations with all of the objective tests. The D-dimer is known to be a marker of the lysis of intravascular cross-linked fibrin as a result of the activation of the endogenous fibrinolytic pathways, and the D-dimer assay is these an objective method for diagnosing a pulmonary embolism. This study assessed the benefits of the D-dimer test for diagnosing a pulmonary embolism using semiquantitative latex agglutination. Methods : The latex agglutination results of 185 patients were retrospectively reviewed. The D-dimer test was performed at the time a pulmonary embolism was suspected. Ninety patients(group I) were diagnosis with PE through spiral chest CT or a chest CT angiogram, perfusion/ventilation scans, and/or pulmonary angiogram. Ninety-five patients (group II) were found not to have a pulmonary embolism through the above tests. Results : The male to female ratio and mean age in groups I and II was 37:55, and 57 years old to 50:45 and 52 years old, respectively. When the cut off value for a positive D-dimer assay was set to $500{\mu}g$, the sensitivity, positive predictive value, negative predictive value and specificity was 86.7%, 61.4%, 79.3%, and 48.4%, respectively. Conclusion : The semiquantitative latex agglutination method in the D-dimer test has a lower sensitivity and negative predictive value than the well known ELISA test particularly for small emboli. Therefore, this test is not a suitable screening test for excluding a pulmonary embolism.

• Journal of the Korea Concrete Institute
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• v.15 no.1
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• pp.95-101
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• 2003

Drying shrinkage cracking which may be caused by the relatively large specific surface is a matter of grave concern for latex modified concrete(LMC) overlay and rapid-setting cement latex modified concrete(RSLMC) overlay. LMC and RSLMC were studied for field applications very actively in terms of strength and durability in Korea. However, there were no considerations in drying shrinkage. Therefore, the purpose of this dissertation was to study the drying shrinkage properties of LMC and RSLMC with the main experimental variables such as cement types(ordinary portland cement, rapid setting cement), latex contents(0, 5, 10, 15, 20%) and curing days at a same controlled environment of 60% of relative humidity and $20^{\circ}C$ of temperature. The drying shrinkage for specimens was measured with a digital dial gauge of Demec. The test results showed that the drying shrinkage of LMC and RSLMC were considerably lower than that of OPC and RSC, respectively. This might be attributed to the interlocking of hydrated cement and aggregates by a film of latex particles, water retention due to hydrophobic, and colloidal properties of the latexes resulting in reduced water evaporation.

• Journal of Veterinary Clinics
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• v.23 no.4
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• pp.393-399
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• 2006

Ketamine, one of general anesthetics for human and veterinary use, is a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist which interferes with the action of excitatory amino acids. It has been reported to impair various leukocyte functions. In this study, the effect of ketamine on the oxidative burst activity (OBA) of canine peripheral blood leukocytes was examined. The OBA of canine peripheral blood phagocytes was analyzed by flow cytometry system. Ketamine at higher concentration such as $1,000{\mu}M$ exhibited a low viability of leukocytes. Thus, ketamine was used at concentration of 10 to $500{\mu}M$ showing no cytotoxic effect and high cell viability. The OBA of leukocytes in the presence or absence of latex beads was analyzed by addition of dihydrorhodamine 123. The direct treatment of ketamine revealed the inhibitory effect on the OBA of peripheral blood polymorphonuclear cells (PMN) and monocyte-rich cells but not peripheral blood mononuclear cells (PBMC) in the presence of latex beads. However, when latex beads were not added to PMN, its OBA was not inhibited by ketamine. The OBA of PMN and monocyte-rich cells but not PBMC in the presence of latex beads was also inhibited by culture supernatant from ketamine-treated- PBMC but not -PMN. But the OBA of PMN in the absence of latex beads was not inhibited by culture supernatant from PBMC treated with ketamine. Therefore, these results suggested that ketamine has the inhibitory effect on the OBA of canine peripheral blood phagocytes such as neutrophils and monocytes during phagocytic response.