• Korean Journal of Veterinary Research
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• v.46 no.3
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• pp.215-224
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• 2006

In order to search the availability of the lectin extracted from Korean mistletoe(Viscum album coloratum) as an adjuvant for the avian vaccines, attempts were made to determine toxicity of the lectin in chicks and its immunostimulating activity on the inactivated vaccines against Newcastle disease virus(NDV). For the determination of toxicity, the lectin was injected into the thigh muscle of SPF chicks(Charles River) of 1-week-old and observed hematologically and pathologically. For the determination of immunostimulating effects, lectin-adjuvanted, inactivated NDV vaccines were injected into the thigh muscle of SPF chicks in the same age group. Sera of the chicks were examined for the hemagglutination-inhibition(HI) antibodies induced, their HI titers and reaction to the NDV antigens. The data were further compared with those from aluminum hydroxide [$Al(OH)_3$]-adjuvanted vaccines and vaccines without adjuvant, and the results are as follows. There were no significant changes observed in the values of RBC, WBC, Hb, PCV, MCV, MCH, MCHC, AST, ALT, BUN, creatinine and total proteins in the chicks administered with lectin of 1.1, 2.2 and $22.2{\mu}g/kg$ body weight, which means the lectin has no effects on blood values and functions of liver and kidney. In histopathologic observation, no lesions were observed in the brain, heart, liver, lung, spleen, kidney, thymus and bursa of Fabricius of the chicks administered with lectin of 1.1, 2.2 and $22.2{\mu}g/kg$ body weight. There were inflammatory lesions, such as congestion, hemorrhage, edema, infiltration of macrophages and coagulation necrosis observed in the thigh muscle of chicks administered with lectin of $22.2{\mu}g/kg$ body weight, whereas no changes were observed in 1.1 and $22.2{\mu}g/kg$ lectin administered chicks. In chicks immunized with lectin($4.4{\mu}g/kg$ of body weight)-adjuvanted B1, LaSota and Ulster 2C vaccines, HI titers in reciprocal values for $log_2$ were 1.8-2.2 at 1 week after vaccination, which was similar with those of 1.5-2.9 by $Al(OH)_3$-adjuvanted vaccines. The HI titers by the lectin-adjuvanted vaccines reached to 3.9-5.3 at 4 weeks, whereas those by the $Al(OH)_3$-adjuvanted vaccines were more high as 7.3-9.3. Meanwhile, the immunostimulating effects of the lectin were recognized while compared to the HI titers with 2.4-3.7 in chicks immunized with vaccines without adjuvants at 4 weeks after vaccination. The chicks immunized with lectin-adjuvanted vaccines were enough to resist challenges by Kyojeongwon strain, a very virulent NDV at 4 weeks after vaccination as well as chicks immunized with $Al(OH)_3$-adjuvanted vaccines. The HI titers by the lectin-adjuvanted vaccines reached to high level as 8.7-10.3 as those with 8.2-9.6 by the $Al(OH)_3$-adjuvanted vaccines at 6 weeks after vaccination, which may be the booster effects by the challenge virus. Antibodies specific to the HN and F antigens of NDV were observed in the sera of both chicks immunized with lectin-adjuvanted vaccines and $Al(OH)_3$-adjuvanted vaccines.

• Journal of Life Science
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• v.25 no.2
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• pp.121-129
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• 2015

Alginates are found in marine brown seaweeds and in extracellular biofilms secreted by some bacteria. Previously, we reported an oligoalginate lyase from Sphingomonas sp. MJ-3 (MJ3-Oal) that had an exolytic activity and protein sequence homology with endolytic polymannuronate (polyM) lyase in the N-terminal region. In this study, the MJ3-Oal was tested for both exolytic and endolytic activity by homology modeling using the crystal structure of Alg17c from Saccharophagus degradans 2-40T. The tyrosine residue at the $426^{th}$ position, which possibly formed a hydrogen bond with the substrate, was mutated to phenylalanine. The FPLC profiles showed that MJ3-Oal degraded alginate quickly to monomers as a final product through the oligmers, whereas the Tyr426Phe mutant showed only exolytic alginate lyase activity. $^1H$-NMR spectra also showed that MJ3-Oal degraded the endoglycosidic bond of polyM and polyMG (polymannuronate-guluronate) blocks. These results indicate that oligoalginate lyase from Sphingomonas sp. MJ-3 probably catalyzes the degradation of both exo- and endo-glycosidic bonds of alginate.

• Korean journal of applied entomology
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• v.13 no.1 s.18
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• pp.41-45
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• 1974

A total of 230 apparently healthy looking potato stocks and 80 potato stocks with symptoms of virus infection were collected from various seed potato farms in Korea and the incidence of potato virus X (PVX), potato virus S (PVS), potato virus M (PVM) and potato virus Y (PVY) was determined by serological microprecipitin tests. Results obtained are as follows. 1. Serological microprecipitin test retreated the presence of PVX, PVS, PVM and PVY in a number of potato stocks grown for the production of seed potatoes in Korea. 2. The occurrence of potato virus M is reported here for the first time in Korea with experimental evidence. 3. Practically $100\%$ (290 stocks, of the apparently healthy looking potato stocks were demonstrated to be infected with both PVX and PVS. The infection percentages of potato stocks with combination of PVX, PVS, PVM and PVY were as follows. PVX+PVS+PVM:$10.3\%$, PVX+PVS+PVY:$4.5\%$, PVX+PVS+PVM+PVY:$1.03\%$ 4. Irish Cobbler and Shimabara, which are the two major potato varieties in Korea, appear to be symptomless carriers of PVX and PVS. However, when these varieties were infected additionally with PVY, usually severe symptoms resulted. 5. Serological microprecipitin technique appears to be highly suitable for early, quick and reliable diagnosis of PVX, PVS PVM and PVY. It is particularly suited for large scale testing of seed potato stocks for the presence of viruses mentioned above.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.3
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• pp.201-209
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• 2015

The deformed degree of car body varies largely with the collision part from side collision of car-to-car. In case of deformation of car body caused by collision, the movement is different as speed energy changes to strain energy. Generally, in the analysis of traffic accident, the movement of car after the collision is analyzed by law of conservation of motion and the error of energy absorption rate along the deformation of car body can be calibrated by inputting coefficient of restitution, but it is current situation that coefficient of restitution applied by referring to the research results of forward collision and backward collision because the research results of side collision is rare. Vehicle model of finite element method applied by structure of car body and materials of each component was analyzed by explicit finite element method, and coefficient of restitution and collision detection time along contact part of side collision was drawn by analyzing the results. Analysis result acquired through the law of conservation momentum by applying finally-computed coefficient of restitution and crash detection time compared to collision result of actual vehicle. As a result, the reliability of analysis was higher than the existing analysis method were acquired when applying the drawn initial input value that used finite element method analysis model.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.643-653
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• 2013

Recently, there are an increasing number of studies on the method of wrapping the outer wall of granular piles with geosynthetic fibers such as geotextile or geogrid that has a certain level of tensile strength as an alternative method for the ground improvement techniques. In this study, triaxial compression tests are performed on the sand and clay specimen encased with various textiles to evaluate the reinforcing effect with regard to the tensile strength of the textile. Furthermore, triaxial compression tests are performed on the clay specimen inserted by sand only and sand encased with geosynthetics to compare behavioral differences between the conventional sand compaction pile and geosynthetic encased sand pile with regard to the replacement ratio, ${\alpha}_s$ and the tensile strength of the geosynthetics. Based on the experimental results, the strength enhancement due to the textile is affected by the longitudinal tensile strength rather than the transverse one of the applied textile. The effect of the confinement by the textile encasement results in the large increase of the cohesions. The overall behaviors, such as shear strength, pore pressure parameter at failure and stress ratio, of the geosynthetic encased sand pile is quite different from those of the conventional sand compaction pile.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.26 no.5
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• pp.385-392
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• 2013

The finite element method has become the most widely used method of structural analysis and recently, the method has often been applied to complex dynamic and nonlinear structural analyses problems. Even for these complex problems, where the responses are hard to predict, finite element analyses yield reliable results if appropriate element types and meshes are used. However, the dynamic and nonlinear behaviors of a structure often include large deformations in various portions of the structure and if the same mesh is used throughout the analysis, some elements may deform to shapes beyond the reliable limits; thus dynamically adapting finite element meshes are needed in order for the finite element analyses to be accurate. In addition, to satisfy the users requirement of quick real run time of finite element programs, the algorithms must be computationally efficient. This paper presents an adaptive finite element mesh generation scheme for dynamic analyses of structures that may adapt at each time step. Representative strain values are used for error estimates and combinations of the h-method(node movement) and the r-method(element division) are used for mesh refinements. A coefficient that depends on the shape of an element is used to limit overly distorted elements. A simple frame example shows the accuracy and computational efficiency of the scheme. The aim of the study is to outline the adaptive scheme and to demonstrate the potential use in general finite element analyses of dynamic and nonlinear structural problems commonly encountered.

• Journal of Life Science
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• v.17 no.10
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• pp.1400-1405
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• 2007

The effect of supplementation with docosahexaenoic acid into n-3 fatty acid deficient diet on improvement of loaming related brain function was investigated. On the second day after conception, Sprague Dawley strain dams were subjected to a diet containing either n-3 fatty acid deficient (Def) or n-3 fatty acid deficient + docosahexaenoic acid (Def+DHA). After weaning, male pups were fed on the same diet of their respective dams until adulthood. Motor activity and Morris water maze tests were measured at 10 weeks old. In motor activity test, there were no statistically significant differences in moving time and moving distance between the Def and Def+DHA diet groups. The n-3 fatty acid deficient with DHA (Def+DHA) group exhibited a shorter escape latency, swimming time and swimming distance (P<0.05) compared to the n-3 fatty acid deficient group (Def) but there was no difference in resting time and swimming speed between the experimental diet groups. In memory retention trial, the number of crossing of the platform position (region A) was significantly greater than those of other regions for the Def+DHA group. However, the Def group swam randomly without preference for the provisions platform location, indicating poorer memory retention. From those results, supplementation with DHA into the n-3 fatty acid deficient diet improved the spatial loaming ability in rats as assessed by Morris water maze test.

• Journal of Life Science
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• v.19 no.7
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• pp.917-922
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• 2009

The effect of adding docosahexaenoic acid into an n-3 fatty acid adequate diet on the improvement of learning related brain function was investigated. On the second day after conception, Sprague Dawley strain dams were subjected to a diet containing either n-3 fatty acid adequate (Adq, 3.4% linolenic acid) or n-3 fatty acid adequate+docosahexaenoic acid (Adq+DHA, 3.31%linolenic acid plus 9.65% DHA). After weaning, male pups were fed on the same diet of their respective dams until adulthood. Motor activity and Morris water maze tests were measured at 10 weeks. In the motor activity test, there were no statistically significant differences in moving time and moving distance between the Adq and Adq+DHA diet groups. The n-3 fatty acid adequate with DHA (Adq+DHA) group tended to show a shorter escape latency, swimming time and swimming distance compared to the n-3 fatty acid adequate group (Adq), but the differences were not statistically significant. There was no difference in resting time, but the Adq+DHA group showed a higher swimming speed compared to the Adq group. In memory retention trials, the numbers of crossing of the platform position (region A), in which the hidden platform was placed, were significantly greater than those of other regions for both Adq and Adq+DHA groups. Based on these results, adding DHA into the n-3 fatty acid adequate diet from gestation to adulthood tended to induce better spatial learning performance in Sprague Dawley rats as assessed by the Morris water maze test, although the difference was not significant.

• Journal of muscle and joint health
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• v.4 no.2
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• pp.221-237
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• 1997

In an attempt to measure effects of the Programmed Resistance Exercise on the daily performance of patients with rheumatoid arthritis, a quasi-experiment ; non-synchronised control group pre-post-test, was carried out for 8 weeks : from June 3 to November 29, 1996. 25 for the experimental group and 26 for the control group were conveniently sampled among registered out-patients on rheumatoid arthritis clinic of Anam Hospital, Korea University Medical Center. The programmed experimental resistance exercises were carried out by the experimental group five times a week for eight weeks. Before and after experiments, level of functional task performance, functional disability, joint mobility, ESR, CRP, self-efficacy and family support were measured and statistically analysed. The results of the analysis of the effects on the Programmed Resistance Exercise are as follows : 1. A statistically significant post-test effects on functional task performance were revealed : 1) the experimental group climbed up and down the 10 steps of the stairs significantly faster than the control group(P=0.0001). 2) the experimental group walked 100 m significantly faster than the control group (P=0.0000). 3) After the experiment, the experimental group could sit down and get up from chairs with no armrest as low as 30cm, 40cm, 50cm on their on, with no assistance as opposed to the control group who could not sit down and get up from such low chairs (P=0.0084). 4) the experimental group lifted 0-15 kg object up to their own heights with no specific strain than the control group (P=0.0000). 2. A significant reduction in the functional disabilities was revealed in the experimental group(P=0.0017). 3. A notable incresement of the joint mobility was revealed in the experimental group. 4. A decrease in the ESR in both the experimental and the control groups was noticed, however, the difference was not statistically significant (P=0.9546). 5. The CRP of both the experimental and control groups decreased with no significant difference (P=0.6022). 6. The self-efficacy increased significantly in the experimental group(P=0.0042), however, no significant effect of self-efficacy on the actual practice of the program was noticed. 7. The family support revealed to be significantly higher in the experimental group (P=0.0013), however, the effect of the family support on actual practice of the program revealed not significant. Judging from the results of these experiments, the resistance exercise program not only improves the functional capacity of rheumatoid arthritis, but also diminishes their functional disabilities and has a great influence on increasing their joint mobility, self-efficacy, and family support. Concluding, in promoting the daily performance of rheumatoid arthritis, the resistance exercise program would be an appropriate nursing intervention.

• Korean Journal of Microbiology
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• v.45 no.4
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• pp.377-384
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• 2009

Among 27 Bacillus sp. isolated from Meju, a traditional Korean soybean fermented food, a strain MJ-226 was selected due to its strong fibrinolytic activity, and it was identified to be Bacillus subtilis MJ-226 according to morphological and biochemical characterization and sugar utilization. The fibrinolytic enzyme of B. subtilis MJ-226 was maximally produced by cultivating in the Tryptic Soy Broth (TSB) for 24~26 h at $37^{\circ}C$, and the enzymes activity was promoted with adding glucose, fructose, peptone or yeast extract to TSB. The fibrinolytic enzyme was stable at the range of pH from 6.0 to 8.0, and between 35 and $40^{\circ}C$. Also, when the crude enzyme was exposed to various metal ions and chemical inhibitors for 12 h, the enzyme stability was maintained by $MnSO_4$, $CaCl_2$, KCl, and NaCl. However, the stability was destroyed by treatment with $CuSO_4$, $MgSO_4$, $ZnSO_4$, $FeSO_4$, and $BaCl_2$, and the enzyme was unstable in the presence of chemical inhibitors such as iodoacetic acid, leupeptin, phenylmethanesulphonyl fluoride (PMSF), sodium dodecyl sulfate (SDS), thiourea, trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid (CDTA) and ethylenediaminetetraacetic acid (EDTA).