• Fisheries and Aquatic Sciences
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• v.18 no.1
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• pp.73-80
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• 2015

To examine the interrelationship between transgenic insertion patterns and transgene expression profiles in established transgenic fish lines, four stable transgenic marine medaka Oryzias dancena germlines harboring ${\beta}$-actin regulator-driven RFP reporter constructs were selected. The established transgenic strains were characterized with regard to their transgenic genotypes (insertion pattern, concatemer formation, and transgene copy number based on genomic Southern blot hybridization and qPCR assay) and expression characteristics at the mRNA (qRT-PCR), protein (western blot), and phenotypic (fluorescent appearance) levels. From comparative examinations, it was found that transgenic expression at both the transcription and translation levels could be significantly downregulated in transgenic strains, potentially through methylation-mediated transgene silencing that was particularly associated with the formation of a long tail-to-head tandem concatemer in the chromosomal integration site(s). When this occurred, an inverse relationship between the transgene copy number and fluorescence intensity was observed in the resultant transgenic fish. However, with the other transgenic genotype, transgenic individuals with an identical Southern blot hybridization pattern, containing a tandem concatemer(s), had very different expression levels (highly robust vs. low expression strengths), which was possibly related to the differential epigenetic modifications and/or degrees of methylation. The concatemer-dependent downregulation of transgene activity could be induced in transgenic fish, but the overall pattern was strain-specific. Our data suggest that neither a low (or single) transgene copy number nor tandem transgene concatemerization is indicative of strong or silenced transgene expression in transgenic fish carrying a ubiquitous transgene. Hence, a sufficient number of transgenic lineages, with different genotypes, should be considered to ensure the establishment of the best-performance transgenic line(s) for practical applications.

• Biomolecules & Therapeutics
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• v.3 no.2
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• pp.122-131
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• 1995

Five human cancer cell lines (HeLa S3, Hep 3B, KATO III, Hs 683, HeLa MR) and one human normal cell line (WI-38) were examined cell viability, northern blot analysis, western blot analysis, and in situ hybridization for the expression $O_{6}$ -methylguanine-DNAmethyltransferase (MGMT), which can repair $O_{6}$ -methylguanine produced in DNA by alkylating agents. In cell viability test, the lethal sensitivities of each strain against anti-tumor drug N,N-bis(2-chloroethyl)- N-nitrosourea (BCNU) were counted, and both BCNU treated and untreated cell extracts were examined for their MGMT inducibility by RNA dot blot analysis. Cell lines did not show MGMT induction by BCNU pretreatment. Tlle MGMT activity was assayed by measuring the $^3$H radioactivity transferred from the substrate DNA containing [methyl-$^3$H)-O$_{6}$ -methylguanine to acceptor molecules in the cell extracts. Extracts from the majority of tumor strains and normal cells contained substantial MGMT activity of varying degree, while the known Mer$^{[-10]}$ cell (lacked or severely depleted in MGMT activity) Hela MR, and Hs 683 (proved to be Mer$^{[-10]}$ ) were much more sensitive to BCNU than the rest of tumor strains, as measured by cell viability test. Overall results above, KATO III showed the highest expression level of MGMT among the strains examined. Furthermore, with all the tumor and normal strains tested, a good correlation was observed between MGMT expression and cellular resistance to BCNU. The varying levels of expression of MGMT in human cancer cells found in this study should provide a molecular basis for MGMT expression among tumor strains from different tissue origin, the information of antitumor agents selection for chemotherapy of cancers.

• The Journal of the Acoustical Society of Korea
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• v.15 no.5
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• pp.99-106
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• 1996

The noise of a compressor is a major contributor to overall noise radiated from the refrigerator. The major source of the noise is radiated by the vibration of the compressor shell. In this study, to identify the dynamic characteristics of compressor shell, a compressor shell is divided into several components and these are analyzed with a commercial FEM(Finite Element Method) package such as MSC/NASTRAN. Using substructure synthesis method, the dynamic characteristics of the total system is identified. The coherence of each component to the total system is computed by using strain and kinetic energy. To increase the frequency of the first resonance mode which is most effective mode to the noise of the compressor shell, the improving strategy of dynamic characteristics is suggested by changing mass and stiffness of the coherence component to the first mode.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.283-283
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• 2017

The objective of the present study is to analyze the lactic acid bacteria (LAB) effects on rye silage fermentation at different stages. Different stages (Booting, Heading, Flowering, and Late flowering stage) of rye were collected from the National livestock farm, National Institute of Animal Science, South Korea. Rye sample was inculcated with lactic acid bacteria and incubated at the anaerobic condition for three months. The nutrient profile such as crude protein (CP), Acid detergent fibre, Neutral detergent fibre and total digestibility nutrients were increased in both control and LAB inculcated samples at all the stages of rye forage. The pH of rye silage was reduced at both stages by LAB inoculation as compared with control. The lactate content was increased in all stages of rye sample by LAB. The acetate concentration and butyrate was reduced in LAB inoculated rye sample. However, acetate concentration was slightly high in LAB inculcated rye at heading and late flowering stage. The LAB population was greater in LAB inoculated rye sample as compared with control sample. However, the massive population was noted in booting stage of rye than the other stages. It indicates the inoculated LAB is the main reason for increasing fermentation quality in the sample through pH reduction by lactate production. Overall results suggest that the isolated lactic acid bacterium is the potent strain that could be suitable for rye forage fermentation at different stages.

• Journal of Korean Society of Steel Construction
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• v.13 no.1
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• pp.1-8
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• 2001

The purpose of this study is to examine the utility of concretefilled steel tubular column to H-beam connections with tubular stiffener. As a preliminary step. a tensile experiment was undertaken to scrutinize characteristics of the structural behavior that take place between beam flanges and column with tubular stiffener. A total of 4 types of experimental settings were developed as tabular stiffeners are made up 9, 18, and 27 mm of thickness and 50 and 80 mm of height respetively Along with the overall load subsequently the degree of displacement and strain were recorded. Based on the yield line theory results of this of this study were evaluated and further critically reviewed the applicability of the strength formula. This study found that collapse mechanism was emerged on the beam flange as reinforcing tabular stiffeners Complementary studies of this sort, including numerical analyses should be undertaken in order to develope specific design critera.

• Food Science of Animal Resources
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• v.30 no.5
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• pp.730-738
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• 2010

We developed predictive growth models for Staphylococcus aureus and Bacillus cereus on various food matrices consisting primarily of ready-to-eat (RTE) foods. A cocktail of three S. aureus strains, producing enterotoxins A, C, and D, or a B. cereus strain, were inoculated on sliced bread, cooked rice, boiled Chinese noodles, boiled bean sprouts, tofu, baked fish, smoked chicken, and baked hamburger patties at an initial concentration of 3 log CFU/g and stored at 8, 10, 13, 17, 24, and $30^{\circ}C$. Growth kinetic parameters were determined by the Gompertz equation. The square-root and Davey models were used to determine specific growth rate and lag time values, respectively, as a function of temperature. Model performance was evaluated based on bias and accuracy factors. S. aureus and B. cereus growth were most delayed on sliced bread. Overall, S. aureus growth was significantly (p<0.05) more rapid on animal protein foods than carbohydrate-based foods and vegetable protein foods. The fastest growth of S. aureus was observed on smoked chicken. B. cereus growth was not observed at 8 and $10^{\circ}C$. B. cereus growth was significantly (p<0.05) more rapid on vegetable protein foods than on carbohydrate-based foods. The secondary models developed in this study showed suitable performance for predicting the growth of S. aureus and B. cereus on various food matrices consisting of RTE foods.

• Journal of the Korea Concrete Institute
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• v.25 no.5
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• pp.529-537
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• 2013

The aim of the current study is to develop a nonlinear isoparametric layered frame finite element (FE) analysis of FRP strengthened reinforced concrete (RC) beam or column members by a force-based FE formulation. In sections, concrete is modeled in the triaxial stress-strain relationship state and the FRP sheet is modeled as layered composite materials in two-dimension. The element stiffness matrix derived by the force-based FE has the force-interpolation functions without assuming the displacement shape functions. A lateral load test of RC column strengthened by GFRP sheets was analyzed by the developed force-based FE model. From comparative studies of the experimental and analysis results, it was shown to compare with the stiffness FE method that the force-based FE analysis could give more accurate predictions in the overall lateral load-deflection response as well as in nonlinear deformations and damages in the column plastic hinge region.

• Journal of the Korean Geotechnical Society
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• v.20 no.7
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• pp.45-55
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• 2004

In the past it has been often observed that the shear stresses at failure are much smaller than the shear strength obtained from traditional laboratory tests and conventional analysis technique is inadequate in stiff soil, such as cemented sand. Many researchers have brought attention to the fact that the presence of flaws i.e. fissures, cracks, joints have a great effect on the strength and overall stress-strain behavior of such materials. They have thought that fracture mechanics may appropriately be adopted as a good tool for analysis of these materials. However, the use of fracture mechanics concept especially for cemented sands is faced with difficulties in obtaining relevant parameters, because fracture parameters and predictions are highly dependent on the material constituents and the size of specimens as well as the size of particles. This paper addresses the effects of sizes which include specimen and aggregate on fracture properties of cemented sand. The results of laboratory tests show that the sizes of specimens and particle have a great effect on the fracture properties such as nominal strength of cemented sand.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.4
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• pp.550-556
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• 2009

This study was designed to evaluate the effects of dietary prebiotic (mannan oligosaccharide = MOS) and probiotic (Saccharomyces cerevisiae = SC) in finishing turkey diets on carcass, cut yield, meat composition and colour. A total of 72 ten-weeksold Big6 male turkey poults were used in the trial. There were eight replicate floor pens per floor with three birds in each. The experiment lasted up to 20 wks of age. The trial was set up as a completely randomized design with 3 dietary treatments. The treatments were: i) negative control (C, no additive); ii) MOS 1 g per kg of diet and iii) SC 1 g per kg of diet (strain SC47, $300{\times}10^{10}$ CFU/kg). Body weight (BW) and feed intake were determined for each of the two week intervals. Twenty-four birds were slaughtered and eviscerated to determine carcass, carcass parts and internal organ weights at 20 wks of age. Meat colour and pH levels were measured 24 h after slaughter. The dietary treatments did not affect BW and average daily gain during the trial (p>0.05). The average daily feed intake and feed conversion ratio of turkey toms fed with MOS were higher than those of control and SC groups during the overall period (p<0.05). The dietary treatments did not affect carcass yield, breast meat, thigh, wing, liver, heart, empty gizzard, intestine, and abdominal fat pad proportions and meat pH, composition and pigmentation (p>0.05). These results suggest that the addition of MOS and SC is not likely to produce any performance or carcass characteristics in finishing turkeys at 10 to 20 wks of age.

• Advances in Computational Design
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• v.3 no.3
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• pp.233-267
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• 2018

Conventional seismic design of concentrically braced frame (CBF) structures suggests that the gusset plate connecting a steel brace to beams and/or columns should be designed as non-dissipative in earthquakes, while the steel brace members should be designed as dissipative elements. These design intentions lead to thicker and larger gusset plates in design on one hand and a potentially under-rated contribution of gusset plates in design, on the other hand. In contrast, research has shown that compact and thinner gusset plates designed in accordance with the elliptical clearance method rather than the conventional standard linear clearance method can enhance system ductility and energy dissipation capacity in concentrically braced steel frames. In order to assess the two design methods, six cyclic push-over tests on full scale models of concentric braced steel frame structures were conducted. Furthermore, a 3D finite element (FE) shell model, incorporating state-of-the-art tools and techniques in numerical simulation, was developed that successfully replicates the response of gusset plate and bracing members under fully reversed cyclic axial loading. Direct measurements from strain gauges applied to the physical models were used primarily to validate FE models, while comparisons of hysteresis load-displacement loops from physical and numerical models were used to highlight the overall performance of the FE models. The study shows the two design methods attain structural response as per the design intentions; however, the elliptical clearance method has a superiority over the standard linear method as a fact of improving detailing of the gusset plates, enhancing resisting capacity and improving deformability of a CBF structure. Considerations were proposed for improvement of guidelines for detailing gusset plates and bracing members in CBF structures.