• Journal of Magnetics
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• v.5 no.1
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• pp.1-3
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• 2000

We have theoretically investigated changes in reflection coefficients induced by misfit strain located near the interface between an iron-yttrium garnet magnetic film and a nonmagnetic gadolinium-gallium garnet substrate in a transverse magneto-optical configuration.

• Transactions of Materials Processing
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• v.23 no.2
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• pp.82-87
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• 2014

The plastic strain ratio is one of the factors that affect the deep drawability of Al alloy sheet. The deep drawability of Al alloy sheet is limited because of its low plastic strain ratio. Therefore an increase in the plastic strain ratio to improve the deep drawability of Al alloy sheet is needed. The current study investigated the increase of the plastic strain ratio and the change in texture of AA5083 Al alloy sheet after a 2 step asymmetric rolling with heat treatments. The average plastic strain ratio of initial AA5083 Al alloy sheets was 0.83. After the first asymmetric rolling step of 88% deformation and subsequent heat treatment at $320^{\circ}C$ for 10 minutes the value was still 0.83. After the second asymmetric rolling of 14% reduction and subsequent heat treatment at $330^{\circ}C$ for 10 minutes the plastic strain ratio rose to 1.01. The average plastic strain ratio after the 2 step asymmetric rolling and heat treatment is 1.2 times higher than that of initial AA5083 Al alloy sheet. This result is related to the development of ND/<111> texture component after the second asymmetric rolling and heat treatment.

• Journal of the Korean Geotechnical Society
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• v.40 no.3
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• pp.65-75
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• 2024

This study investigates liquefaction-induced settlement through strain-controlled tests using a cyclic direct simple shear device on clean sand specimens. By focusing on the accumulated shear strain, soil density, sample preparation method, and cyclic waveshape, this study attempts to enhance the understanding of soil behavior under seismic loading and its further deformation. Results from tests conducted on remolded samples reveal insights into excess pore water pressure development and post-liquefaction volumetric strain behavior, with denser samples exhibiting lower volumetric strains than looser samples. Similarly, the correlation between the frequency and amplitude variations of the wave and volumetric strain highlights the importance of wave characteristics in soil response, with shear strain amplitude changes, varying the volumetric strain response after reconsolidation. In addition, samples prepared under moist conditions exhibit less volumetric strain than dry-reconstituted samples. Overall, the findings of this study are expected to contribute to predictive models to evaluate liquefaction-induced settlement.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.71-77
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• 2008

Microstructural changes may arise due to the particle vanishing, fluid diffusion, heating, etc. This study focuses on the changes in small-strain shear stiffness in k0 loading produced by local straining in particular system made of sand-salt mixtures. Local strains were induced by dissolution of salt particles. Experiments were carried out in a conventional oedometer cell equipped with bender elements. Axial displacement and shear wave signals are recorded at each loading stage and during saturation process. Experimental data showed that microstructural changes due to particle vanishing were clearly captured by using shear wave measurement. Saturation of sand-salt mixture at a larger axial stress did not always create a more condense soil at the end of loading stage. Sand-salt mixture is useful for laboratory test on controlled artificial specimen.

• Mycobiology
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• v.42 no.4
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• pp.353-360
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• 2014

Makgeolli is a traditional Korean alcoholic beverage. The flavor of makgeolli is primarily determined by metabolic products such as free sugars, amino acids, organic acids, and aromatic compounds, which are produced during the fermentation of raw materials by molds and yeasts present in nuruk, a Korean fermentation starter. In this study, makgeolli was brewed using the wild yeast strain Saccharomyces cerevisiae Y98-5, and temporal changes in the metabolites during fermentation were analyzed by ultra-high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry. The resultant data were analyzed by partial least squares-discriminant analysis (PLS-DA). Various metabolites, including amino acids, organic acids, sugar alcohols, small peptides, and nucleosides, were obviously altered by increasing the fermentation period. Changes in these metabolites allowed us to distinguish among makgeolli samples with different fermentation periods (1, 2, 3, 6, 7, and 8 days) on a PLS-DA score plot. In the makgeolli brewed in this study, the amounts of tyrosine ($463.13{\mu}g/mL$) and leucine ($362.77{\mu}g/mL$) were high. Therefore, our results indicate that monitoring the changes in metabolites during makgeolli fermentation might be important for brewing makgeolli with good nutritional quality.

• Food Science of Animal Resources
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• v.35 no.2
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• pp.171-178
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• 2015

This study aimed to investigate the effects of Lactobacillus plantarum FH185 on the reduction of adipocyte size and gut microbial changes in mice with diet-induced obesity. The strain was found to have a lipase inhibitory activity of 70.09±2.04% and inhibited adipocyte differentiation of 3T3-L1 cells (18.63±0.98%) at a concentration of 100 µg/mL. To examine the effect of the strain supplementation on gut microbial changes in mice with diet-induced obesity, male C57BL/6J mice were fed on four different diets (i.e., A, normal diet (ND); B, high-fat diet (HFD); C, HFD with ABT-3 (10⁹ CFU/day); and D, HFD with L. plantarum FH185 (10⁹ CFU/day)) for 6 wk. According to the results of fecal pyrosequencing, the ratio of Firmicutes to Bacteroidetes in groups C and D was lower than in the control groups at the phylum level. At the family level, Lactobacillaceae in groups C and D was observed to dominate, while Lachnospiraceae in groups A and B was observed to dominate. At the genus level, Lactobacillus in groups C and D was comparatively higher than in groups A and B. To examine the effects of strain supplementation on the reduction of adipocyte size, the left and right epididymal fat pads were quickly isolated after the animals were sacrificed, and the adipocyte sizes were measured. In groups A, C and D, the percentage of 2,000 m² of adipocyte was higher than in the other size of adipocyte, while the percentage of over 5,000 m² of adipocyte was highest in group B. The mean adipocyte size of group D was significantly larger than that of group A, but smaller than that of group B.

• Tunnel and Underground Space
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• v.13 no.4
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• pp.321-329
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• 2003

The change of strain-dependent hydraulic conductivity around mined panels due to subsidence is examined where normal and shear strains, modulus reduction ratio and joint spacing are major factors controlling the changes of hydraulic conductivity. Modulus reduction ratio and joint spacing are defined through RMR and RQD, respectively. Utilizing these two empirical parameters, changes of hydraulic conductivity values of a full gamut of rock mass conditions are determined. The change of hydraulic conductivity is not apparent in the near surface area and more significant change takes place in the area around mined panels. A zone of strong influence from the subsidence extends to a height of approximately 20m above mined panels. The shear strain does also play the role of increasing a hydraulic conductivity around mined panels. As RMR of rock mass decreases, a hydraulic conductivity is found to be increased and this means that subsidence in a poor rock with low RMR has a great effect on a hydraulic conductivity field.

• Journal of Microbiology and Biotechnology
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• v.27 no.7
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• pp.1345-1358
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• 2017

The impact of overproduction of a heterologous protein on the metabolic system of host Lactococcus lactis was investigated. The protein expression profiles of L. lactis IL1403 containing two near-identical plasmids that expressed high- and low-level of the green fluorescent protein (GFP) were examined via shotgun proteomics. Analysis of the two strains via high-throughput LC-MS/MS proteomics identified the expression of 294 proteins. The relative amount of each protein in the proteome of both strains was determined by label-free quantification using the spectral counting method. Although expression level of most proteins were similar, several significant alterations in metabolic network were identified in the high GFP-producing strain. These changes include alterations in the pyruvate fermentation pathway, oxidative pentose phosphate pathway, and de novo synthesis pathway for pyrimidine RNA. Expression of enzymes for the synthesis of dTDP-rhamnose and N-acetylglucosamine from glucose was suppressed in the high GFP strain. In addition, enzymes involved in the amino acid synthesis or interconversion pathway were downregulated. The most noticeable changes in the high GFP-producing strain were a 3.4-fold increase in the expression of stress response and chaperone proteins and increase of caseinolytic peptidase family proteins. Characterization of these host expression changes witnessed during overexpression of GFP was might suggested the metabolic requirements and networks that may limit protein expression, and will aid in the future development of lactococcal hosts to produce more heterologous protein.

• Journal of Microbiology and Biotechnology
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• v.7 no.5
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• pp.287-292
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• 1997

The role of glyoxylate bypass in lysine production by Corynebacterium glutamicum ssp. lactofermentum ATCC21799 was analyzed by using cloned aceA and aceB genes which encode enzymes catalyzing the bypass. Introduction of a plasmid carrying aceA and aceB to the strain increased enzyme activities of the bypass to approximately 5 fold on acetate minimal medium. The strain with amplified glyoxylate bypass excreted 25% more lysine to the growth medium than the parental strain, apparently due to the increased availability of intracellular oxaloacetate. The final cell yield was lower in the strain with amplified glyoxylate bypass. These changes were specific to the lysine-producing C. glutamicum ssp. lactofermentum ATCC21799, since the lysine-nonproducing wild type Corynebacterium glutamicum strain grew faster and achieved higher cell yield when the glyoxylate bypass was amplified. These findings suggest that the lysine producing C. glutamicum ssp. lactofermentum ATCC21799 has the ability to efficiently channel oxaloacetate, the TCA cycle intermediate, to the lysine biosynthesis pathway whereas lysine-nonproducing strains do not. Our results show that amplification of the glyoxylate bypass efficiently increases the intracellular oxaloacetate in lysine producing Corynebacterium species and thus results in increased lysine production.

• Journal of the Korea Concrete Institute
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• v.15 no.5
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• pp.747-758
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• 2003

The moment-curvature envelope describes the changes in the flexural capacity with deformation during a nonlinear analysis. Therefore, the moment-curvature analysis for reinforced concrete columns, indicating the available flexural strength and ductility, can be conducted providing the stress-strain relation for the concrete and steel are known. The moments and curvatures associated with increasing flexural deformations of the column may be computed for various column axial loads by incrementing the curvature and satisfying the requirements of strain compatibility and equilibrium of forces. Clearly it is important to have accurate information concerning the complete stress-strain curve of confined high-strength concrete in order to conduct reliable moment-curvature analysis that assesses the ductility available from high-strength concrete columns. However, it is not easy to explicitly characterize the mechanical behavior of confined high-strength concrete because of various parameter values, such as the confinement type of rectilinear ties, the compressive strength of concrete, the volumetric ratic and strength of rectangular ties. So a stress-strain model is developed which can simulate complete inelastic moment-curvature relations of high-strength concrete columns.