• Steel and Composite Structures
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• v.21 no.5
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• pp.1105-1119
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• 2016

In this study, it is presented that a new developed approach for equivalent area-distributed loading (EADL) induced from a single concentrated force. For the purpose, a full scale 3D steel formwork system was constructed in laboratory conditions. A developed load transmission platform was put on the formwork system and loaded step by step on the mass center. After each load increment, displacement was measured in several crictical points of the system. The developed platform which was put in to slab of formwork to equivalently distribute the load from a point to the whole slab was constituted using I profiles. A 3D finite element model of the formwork system was analyzed to compare numerical displacement results with experimental ones. In experimental tests,difference among the displacements obtained from reference numerical model (model applied EADL) and main numerical model (model applied single load using a load cell via load transmission platform) is about %13 in avarage. Difference among the displacements obtained from experimental results and main numerical model under 30 kN single load is about %11 in avarage. The results revealed that the displacements obtained experimentally and numerically are dramatically closed to each other. It is highlighted from the study that the developed approach is reliable and useful to get EDL.

• Toxicological Research
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• v.13 no.3
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• pp.193-196
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• 1997

Matricaria Chammomillal L., Foemiculum Vulgare mill, and Plantago Psylium L. have been screened for their hepato protective activities against liver damge induced by $CCl_4$ intoxication in mice. Hydroalcoholic extractions (2:8) of herbal drugs were concentrated in vacuo and concentrated crude extracts of Matrica Chammomilla L. and Foeniculum Vulgare mill were orally administered at doses of 100 mg/kg, 200 mg/kg, 400 mg/kg, and 800 mg/kg. Plantago Psyllium was given at doses of 50 mg/kg, 100 mg/kg, 200 mg/kg, and 400 mg/kg. Liver protective activities of these herbs were determined after administration of $CCl_4$ Liver size, serum enzyme activities, sleeping time, and histopatology of the liver were examined one hour after administration of $CCl_4$. ALT and AST activities, liver weight and sleeping time decreased in groups that received 400 mg/kg of Matricaria Chammomilla L. or Foeniculum Vulgare. Histological investigation showed significant increase in hepatic cell regeneration and reduction in liver injury. The group that received 100 mg/kg Plantago Psylium showed liver protection but protection was not significant in other doses.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.2
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• pp.151-156
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• 2008

Different kinds of forces can be applied to the biological tissue. The analysis of the applied force is highly important to explain the mechanism of cellular response. In this study, the applied force to the collagen gel was analyzed by the finite elements analysis. The model received two different kinds of static force (compression and tension). The force range was 50g to 400g. In results, von Mises stress was concentrated in the peripheral region in the compression model. It was concentrated in the central area in the tension model. However, the compressive force was high in the peripheral area of the compression model and the tensional force was also high in the same area of the tension model. In conclusion, the applied force could be different to the region and it should be considered in the experiment to analyze the effects of the mechanical force on the cells.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.5
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• pp.694-702
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• 2014

One of the most important devices in an underwater vessel is a propulsion system. It should be a quiet and efficient system for stealthy operations in the large mission area. Hence lead-acid battery system has been used to supply the energy to electric motor. Recent technological developments and improvements, such as polymer electrolyte membrane(PEM) fuel cell and lithium polymer battery and have created the potential to improve overall power and propulsion performance. An underwater vessel always starts their mission with a limited energy and is not easy to refuel. Therefore design of energy elements, such as fuel cell and battery, and their load distribution are important to increase the maximum operating time of underwater vessel. In this paper, the lead-acid battery/PEM fuel cell and lithium polymer battery/PEM fuel cell were suggested as propulsion system and their performances were analyzed by modeling and simulation using Matlab/Simulink. Each model concentrated on representing the characteristics of energy element depending on demand current. As a result the effect of load distribution between battery and fuel cell was evaluated and the operation time of each propulsion system was able to be estimated exactly.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.6
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• pp.520-527
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• 2013

In this paper, a joint cell grouping and user association technique proposed for a semi-dynamic grouped network MIMO in a clustered heterogeneous cellular network (HCN). With the conventional macro BSs, small cells are being overlaid to increase a spectral efficiency per area and these small cells are expected to be concentrated to support exponentially increasing data traffic in hot spot areas. The main culprits of performance degradation in the clustered HCN are interference and load imbalance. The proposed scheme jointly handles them to maximize a proportional-fair metric. It is shown that the proposed technique can largely improve user average rate and proportional fairness among users than any other conventional schemes in the clustered HCN.

• Parasites, Hosts and Diseases
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• v.54 no.4
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• pp.431-437
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• 2016

The study of antigenic epitopes from Toxoplasma gondii has not only enhanced our understanding of the structure and function of antigens, the reactions between antigens and antibodies, and many other aspects of immunology, but it also plays a significant role in the development of new diagnostic reagents and vaccines. In the present study, T. gondii GRA6 epitopes were identified using bioinformatics tools and a synthetic peptide technique. The potential B cell epitopes of GRA6 predicted by bioinformatics tools concentrated upon 3 regions of GRA6, 1-20 aa, 44-103 aa, and 172-221 aa. Ten shorter peptides from the 3 regions were synthesized and assessed by ELISA using pig sera from different time points after infection. Three of the 10 peptides (amino acids 44-63, 172-191, and 192-211) tested were recognized by all sera and determined to be immunodominant B-cell epitopes of GRA6. The results indicated that we precisely and accurately located the T. gondii GRA6 epitopes using pig sera collected at different time points after infection. The identified epitopes may be very useful for further studies of epitope-based vaccines and diagnostic reagents.

• Biomolecules & Therapeutics
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• v.4 no.1
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• pp.46-50
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• 1996

Inhibition of the growth of human cancer cells by proteins secreted from 373-L1 cells was investigated in the present study. The growth of human cancer cells was inhibited by co-culture with 373-L1 cells under 10% FBS and DME, DME, GIT and serumless medium, respectively. The conditioned medium of cultured 373-L1 cells under serumless medium was concentrated 100-fold through an ultrafiltration cell with a 10,000 molecular weight cutoff at 4$^{\circ}C$ under positive pressure using nitrogen(373-L1 EM). 373-L1 EM inhibited the growth of HeLa, Hep G 2, KHOS-Np, A43l and MCF-7 cells. 3T3-L1 EM was purified with FPLC, DEAE-ion exchange chromatography and phenyl-sepharose chromatography. The major protein of 373-L1 EM has a molecular weight of 66,000-68,000 in SDS-PAGE analysis. The results suggest that the inhibitory activity of 373-L1 EM appears to be due to some protein(m.w.66,000-68,000) secreted by 373-L1 cells.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.1
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• pp.260-264
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• 2004

The effects of bioactive fractions from Brachyglottis monroi on biological activity were investigated. this bioactive subfraction 6-5 is the most cytotoxic to P388 murine leukaemia cell lines. A comparison of IC/sub 50/ values of these subfraction in cancer cell lines showed that their susceptibility to these subfractions decreased in the following order; Fr. 6-5 > Fr. 6-3 > Fr. 6-6 > Fr. 6-1 > Fr. 6-2 > Fr. 6-4 by the MTT method. Silica gel flash column chromatography concentrated the cytotoxic activity in subfraction 6-5 which eluted with 30% and 40% ethyl acetate : hexane gave a major bioactive (51 mg, P388 IC/sub 50/ 8,286 ng/mL at 7.5 ㎍/disc).

• Environmental Analysis Health and Toxicology
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• v.8 no.3_4
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• pp.7-12
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• 1993

An Actinomycete strain isolated from Mt. Dea-Dun had a strong antifungal activity. The culture brith produced by isolated strain showed only antifungal activity against fungi with the exception of yeast and bacteria. It was heat stable, dissolved in ehtylacetate. The concentrated antifungal agent showed cytotoxicity against HEP-2 and HeLa as tumor cell line, and showed weak cytotoxicity against VERO 36 as normal cell line. Morphological and physiological characteristics were tested with isolated strain. The spore color of isolated strain was gray. It had a short chain and produced brown colored lytic substance in yeast extract-malt agar. The cell wall of isolated strain was composed of meso-DAP, and we suggested it as genus Actinomadura. In the existing of chemical inhibitor, isolated strain grew on the condition of 0.0001% crystal violet, 0.1% phenol, 0.01% sodium azide and 10% sodium chloride. Carbon utilization of isolated strain was shown that glucose, sucrose, manitol and sodium citrate were well utilized.

• Journal of Ceramic Processing Research
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• v.19 no.6
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• pp.492-498
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• 2018

In this study, a sea shell was converted into bioceramic phases at three different sintering temperatures ($450^{\circ}C$, $850^{\circ}C$, $1000^{\circ}C$). Among the obtained bioceramic phases, a valuable ${\beta}-TCP$ was produced via mechanochemical conversion method from sea snail Turritella terebra at $1000^{\circ}C$ sintering temperature. For this reason, only the bioceramic sintered at $1000^{\circ}C$ was concentrated on and FT-IR, SEM/EDX, BET, XRD, ICP-OES analyses were carried out for the complete characterization of ${\beta}-TCP$ phase. Biodegradation test in Tris-buffer solution, bioactivity tests in simulated body fluid (SBF) and cell studies were conducted. Bioactivity test results were promising and high rate of cell viability was observed in MTT assay after 24 hours and 7 days incubation. Results demonstrated that the produced ${\beta}-TCP$ bioceramic is qualified for further consideration and experimentation with its features of pore size and ability to support bone tissue growth and cell proliferation. This study suggests an easy, economic method of nanobioceramic production.