• Journal of the Korea Institute of Building Construction
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• v.3 no.3
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• pp.107-112
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• 2003

This study is to investigate the properties of concrete with crushed sand on site and to propose a quality guideline for its use as artificial sand and concrete. From our experimental result in laboratory and site, we found that demand water of concrete with crushed sand for target slump increased by 18kg/m3 compared to mixed sand and l8kg/m3 compared to sea sand respectively. The compressive strength increased by around 3∼6% when compared to concrete with sea sand. Accordingly, our study showed that the combined sand mixed with sea sand would be desirable to obtain workability and strength of concrete including dry shrinkage and bleeding test. Furthermore, the optimal replacement percentage of crushed sand was 50% with sea sand. As such, crushed sand would be sufficient as fine aggregate for concrete in terms of economic efficiency and quality. Crushed sand, on the other hand can only be used as fine aggregate when VFS(Very Fine Sand) is below 3.5 percentage of weight of sand and particle shape is above 55 percentage. Also, the particle shape and microsand passing NO.200 sieve should continually be improved to increase workability of concrete on site.

• Journal of Ceramic Processing Research
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• v.19 no.6
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• pp.509-513
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• 2018

This study uses fly ash for non-shrinkage grout in order to develop strength of grout and improve its durability. We grind fly ash to the extent of $7,000cm^2/g$ and use ground fly ash and raw fly ash respectively at the proportion of 10%, 20%, 30% instead of OPC and compare the results drawn on the condition of each proportion. As a mixed material of grout, EVA and water-reducing agent is added in order to prevent bleeding and improve segregation resistance, CSA is added with a view to preventing drying shrinkage and improving early strength property. In regard to flow and flow time test for analyzing and evaluating workability, it is revealed that grouts of all mix proportions except raw fly ash 30% mix proportion satisfy all performance criteria. With regard to length change rate, grout with no admixture shows the highest shrinkage rate, but the rate is 0.0005%, extremely insignificant rate. As material age increases, compressive strength of two grouts, that is to say ground fly ash 10% and 20%-used grouts, exceed that of grout with no admixture or show high-level compressive strength.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.1
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• pp.41-57
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• 1997

The present study investigated the effects of hyperbaric oxygen therapy on periodontal wound healing of replanted rat tooth. 80 rats (Sprague-Dawley strain) weighting $130{\pm}5gm$ were selected and divided into experimental and control group, each group consisting of 40 rats. Rats were administered 0.4% ${\beta}$-aminoproprionitrile for 5 days to achieve gentle tooth extraction. The maxillary first molars were extracted under anesthesia with pentobarbital, washed in sterile distilled water, treated with bacterial collagenase to remove collagen fibers on the root surfaces. After washing in water overnight, the mesial root surface were demineralized by application of citric acid, washed, dried and stored at $4^{\circ}C$. Immediately after tooth extraction and bleeding control, the treated molars extracted previously from other rats were replanted. The experimental group was exposed to hyperbaric oxygen at 2.5 atm. for 2 hrs. a day during experimental period. Eight animals of each group were sacrificed 1, 3, 6, 8, 10 days after reimplantation of teeth by intracardiac perfusion with 4% paraformaldehyde. The replanted molars and surrounding tissues were cut, demineralized, dehydrated and embedded in paraffin. Sections were stained with azan, toluidine blue and hematoxylin. Some other sections were stained by means of immunostaining achieved by the avidinbiotin complex method. The results as follows; 1. Experimental group showed fast healing of gingival epithelium. 2. Macrophage and newly formed blood vessels appeared early in the gingival connective tissue of experimental group. 3. Experimental group showed fast, abundant fibroblast proliferation and regularity of collagen fiber. 4. In both group, collagen was distributed along the collagen fiber. The distribution was strong and regular in the experimental group. 5. In the regenerated periodontal ligament of experimental group, fibers showed regular arrangement and invaded root surface fast.

• The Journal of Engineering Geology
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• v.28 no.1
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• pp.61-67
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• 2018

Grouting is reinforcement or cutoff method which uses the hardening agent which is typically represented by portland cement and injected into the ground or the structure. When mixing the cement in powder form with water, the particles tend to cohere each other. Once they cohered, the particle size tends to become larger while injection efficiency becomes lower. This study, in a bid to reduce the cohesion of cement, the screen was set inside the grout mixer so that the cement particles are separated while vibrating them. To validate the effect of vibration screen, comparison test was conducted by using ordinary portland cement, slag cement and micro cement. Viscosity test, bleeding test and grain-size analysis indicated that the characteristics varied significantly after passing through the vibration filter. It is expected that the vibration filter installed inside the grout mixer will reduce the cement cohesion when mixing with water.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.1
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• pp.9-13
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• 2009

Flos Sophora japonica L. (Leguminosae), commonly called scholar tree, is a well-known traditional medicine used for the treatment of bleeding and as an antihemorrhagic agent. This research was conducted to determine biofunctional activities of Flos Sophora japonica extract. Methanolic extract from Flos Sophora japonica was partitioned by using organic solvents, including n-hexane, ethyl acetate, n-butanol, and water. Ethyl acetate soluble fraction showed the strongest antioxidant activity ($RC_{50}=3.13{\mu}g/mL$) among the fractions. In antimicrobial activity assays, ethyl acetate soluble fraction was effective to bacterial inhibition, such as Escherichia coli and Klebsiella pneumonia, with minimum inhibitory concentrations in $125{\mu}g/mL$. In anticomplementary activity assays, water soluble fraction was the most effective exhibiting 21% inhibitory activity.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.5
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• pp.773-786
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• 2018

In this paper, viscosity features of sealant (bentonite-cement slurry), which is used for umbrella arch method in tunnel, were studied. The sealant must secure optimal strength and capacity for the waterproof and stabilization of borehole as well as to satisfy groutability. In this study, the variation of viscosity was measured with different mixing processes. With an increase of initial mixing period with water and bentonite mixture, the required time for the rapid increase of viscosity of the sealant is shorten. With increase of mixing period, the possibility of swelling of bentonite will increases and this can lead increase of the viscosity of the mixture. In addition, the behaviors of sealant vary with a drastic increase of the viscosity: thixotropy and rheopexy. Furthermore, the bentonite/water mixing period influences on the bleeding features of the sealant. Further study is required to introduce the guideline, which can be applicable in the field in the aspect of required capacity of the sealants and mixing processes of the ingredients.

• Herbal Formula Science
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• v.24 no.4
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• pp.259-269
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• 2016

Objectives : Phyllostachys Folium is leaves of Phyllostachys nigra var. henesis $S_{TAPF}$. In the East Asian traditional medicine, the herb has been used to treat nasal bleeding, dysuria, epilepsy and etc. The present study was conducted to evaluate the anti-inflammatory effects of the Phyllostachys Folium water extracts (PFE) in vitro and in vivo model. Methods : Cell viability was measured by MTT assay after the treatment of PFE and NO production was monitored by measuring the nitrite content in culture medium. iNOS, COX-2, $I{\kappa}B$, $p-I{\kappa}B{\alpha}$ amd $NF{\kappa}B$ were detected by immunoblot analysis, and levels of cytokine were analyzed by sandwich ELISA kit. Anti-edema effect of PFE was determined in the carrageenan-induced paw edema model in rats. Results : LPS increased NO and cytokines levels compared with control, these increases were attenuated by PFE. In addition, LPS-induced pro-inflammatory proteins such as iNOS, COX-2 were down regulated by PFE. These anti-inflammatory effect of PFE results from inhibition of phosphorylation of $I{\kappa}B$ and translocation of $NF-{\kappa}B$. Conclusion : These results show that PFE has some anti-inflammatory effects which might play a role in gram-negative bacterial infection inflammation and $NF{\kappa}B$ activated diseases.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.1
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• pp.101-109
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• 2004

Spatholobus suberectus belonging the family Leguminosae has been used for promoting blood circulation, removing blood stasis, tonifying the blood, relaxing tendons, stopping internal bleeding and eliminating dampness in oriental traditional medicine. This study investigates whether the water extracts of S. suberectus induce apoptotic cell death in Jurkat T-acute lymphoblastic leukemia (ALL) cells. Jurkat cells were increased inhibitions of cell viability in a concentration-dependent manner by S. suberectus, as measured by cell morphology. The capability of S. suberectus to induce apoptosis was associated with proteolytic cleavage of specific target protein such as poly (ADP­ribose)polymerase protein suggesting the possible involvement of caspases. The purpose of the present study is also to investigate the effect of S. suberectus on cell cycle progression. G1 checkpoin related gene products tested (cyclin D1, cyclin dependent kinase 4, retinoblastoma, E2Fl) were decreased in their protein levels in a dose-dependent manners after treatment of the extract. These results indicate that the increase of apoptotic cell death by S. suberectus may be due to the inhibition of cell cycle progression in wild type p53-lacking Jurkat cells.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.2
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• pp.491-497
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• 2007

Hyeonggaeyeongyo-tang (HYT; Jingjielianqiao-tang), is known to be effective in lowering wind-heat blended as a pathogen of kidney. HYT has been traditionally used for the treatment of a syndrome in kidney meridian, due to invasion of pathogenic wind and heat. Nowadays, this prescription is used to treat diseases marked by excessive wind and heat in the kidney meridian, such as acute otitis media, empyema, hypertrophic rhinitis, nasal bleeding, nasal obstruction, acne and tonsillitis. The present study was conducted to evaluate the effect of HYT on the regulatory mechanism of cytokines and nitric oxide (NO) for the immunological activities in Raw 264.7 cells. After the treatment of HYT water extract, cell viability was measured by MTT assay, NO production was monitored by measuring the nitrite content in culture medium. Cyclooxygenase-2 (COX-2_ and inducible nitric oxide synthase (iNOS) were determined by immunoblot analysis, and levels of cytokine were analyzed by sandwich immunoassays. The production of No was significantly inhibited by pre-treatment (1h) with HYT(0.1-0.3 mg/ml) on LPS-activated Raw264.7 cells. The expression of iNOS and COX-2 protein were up-regulated by LPS, but the increased levels of iNOS and COX-2 were inhibited by pre-treatment of HYT (0.3-1.0 mg/ml), respectively. And the level of interleukin-6 (IL-6), cytokine released from macrophage, was reduced by HYT pre-treatment (0.3-1.0 mg/ml). Thus, the present data suggest that HYT may play an important role in adjunctive therapy in Gram-negative bacterial infections.

• Journal of the Korea Institute of Building Construction
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• v.18 no.3
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• pp.211-218
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• 2018

This study examined the reliability and revision necessity of concrete standard specifications based on the comparisons with test data obtained by using domestic artificial lightweight aggregates and the contents specified in different foreign specifications including ACI 211.2, ACI 213, ACI 301, JASS 5 and CEB-FIP. To achieve the continuous particle distribution of domestic fine lightweight aggregates, the partial addition of natural sand with the maximum size of 2.5mm was required. To control the segregation and excessive bleeding in the fresh lightweight concrete, the current limitations on the water-to-binder ratio and unit water content need to be modified using lower values. In particular, a rational mixture proportion approach of lightweight concrete needs to be established for the targeted requirements of initial slump, 28-day compressive strength, air content and dry unit weight. Ultimately, significant revision of the concrete standard specifications is required considering the characteristics of domestic artificial lightweight aggregates.