• Journal of Adhesion and Interface
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• v.5 no.2
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• pp.14-26
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• 2004

For reliable determination of mechanical characteristics of adhesively bonded joints used e.g. as input data for computer-aided design of complex components, the thick-adherend tensile-shear test according to ISO 11003-2 is the most important material testing method. Although the total displacement of the joint is measured across the polymer layer directly in the overlap zone in order to minimize the influence of the stepped adherends, the substrate deformation must be taken into account within the framework of the evaluation of the shear modulus and the maximum shear strain, at least when high-strength adhesives are applied. In the standard ISO 11003-2 version of 1993, it was prescribed to perform the substrate deformation correction by means of testing a one-piece reference specimen. The authors, however, pointed to the excessive demands on the measuring accuracy of the extensometers connected with this technique in industrial practice and alternatively proposed a numerical deformation analysis of a dummy specimen. This idea of a mathematical correction was included in the revised ISO 11003-2 version of 2001 but in the simplified form of an analytical method based on Hooke's law of elasticity for small strains. In the present work, it is shown that both calculation techniques yield considerably discordant results. As experimental assessment would require high-precision distance determination (e.g. laser extensometer), finite element analyses of the deformation behavior of the bonded joint are performed in order to estimate the accuracy of the obtained substrate deformation corrections. These simulations reveal that the numerical correction technique based on the finite element deformation modeling of the reference specimen leads to considerably more realistic results.

• Structural Engineering and Mechanics
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• v.39 no.1
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• pp.125-145
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• 2011

Pushover analysis has gained significant popularity as an analytical tool for realistic determination of the inelastic behaviour of RC structures. Though significant work has been done to evaluate the demands realistically, the evaluation of capacity and realistic failure modes has taken a back seat. In order to throw light on the inelastic behaviour and capacity evaluation for the RC framed structures, a 3D Reinforced concrete frame structure was tested under monotonically increasing lateral pushover loads, in a parabolic pattern, till failure. The structure consisted of three storeys and had 2 bays along the two orthogonal directions. The structure was gradually pushed in small increments of load and the corresponding displacements were monitored continuously, leading to a pushover curve for the structure as a result of the test along with other relevant information such as strains on reinforcement bars at critical locations, failure modes etc. The major failure modes were observed as flexural failure of beams and columns, torsional failure of transverse beams and joint shear failure. The analysis of the structure was by considering all these failure modes. In order to have a comparison, the analysis was performed as three different cases. In one case, only the flexural hinges were modelled for critical locations in beams and columns; in second the torsional hinges for transverse beams were included in the analysis and in the third case, joint shear hinges were also included in the analysis. It is shown that modelling and capturing all the failure modes is practically possible and such an analysis can provide the realistic insight into the behaviour of the structure.

• Korean Journal of Microbiology
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• v.40 no.1
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• pp.7-11
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• 2004

eIF5B is a translation initiation factor that delivers Met-$tRNA^{Met}$ to AUG start codon and subsequently joins the small and large ribosomes. In order to study the function of eIF5B encoded by FUN12, we constructed FUN12 which lacked 5' end of its sequence. We found that this construct lacking almost all of its promoter in pRS plasmid partially complemented slow growth phenotype of fun12 deletion strain. Interestingly, this construct expressed N-terminally truncated eIF5B and its expression level was about 5% of that of wild type eIF5B. Low amount of the eIF5B expressed additionally in fun12 deletion strain played a direct role as a limiting factor for its growth. This limiting factor eIF5B in those strains also modulates activities of overall translation in vitro.

• Korean Journal of Microbiology
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• v.25 no.4
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• pp.282-289
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• 1987

The characteristics of the plasmid pKU10 isolated from Pseudomonas putida KU816 were investigated and its restriction map was constructed. The pKU10 plasmid was a small R plasmid carrying genes for resistance to ampicillin, tetracyclin, and chloramphenicol, and cured by treatment with mitomycin C. The molecular size of pKU10 was estimated to be 9.4Kb. Pseudomonas strains and E. coli cells could be transformed for antibiotic resistance characters specified by pKU10 plasmid DNA. By incompatibility test with other plasmids, pKU10 is grouped into IncP-1. EcoRI, XhoI, SalI, BglII, and SmaI cleaved pKU10 once, while PstI cleaved at two sites, and HindIII cleaved at six sites. The restriction map was constructed by partial and complete digestion of the purified plasmid DNA with single, double, or triple restriction enzymes. Thus, pKU10 is expected to be used for a cloning vector in Pseudomonas cells.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1266-1270
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• 2000

Quality properties of soy bean pastes made with Aspergillus oryzae and 5 Bacillus strains isolated from traditional soy bean pastes were examined. The pH decreased gradually and contents of amino-type nitrogen increased during fermentation. There were small differences in moisture and crude-protein contents, whereas big difference was observed in reducing sugar, isoflavones and organic acid contents. Isoflavones in the samples made with Bacillus licheniformis F2358 and Bacillus subtilis F2362 were high. Samples made with Bacillus licheniformis F2382 had high contents of organic acid and good score for taste and overall acceptability in sensory evaluation.

• Nano
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• v.13 no.11
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• pp.1850126.1-1850126.10
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• 2018

Flexible strain sensors, as the core member of the family of smart electronic devices, along with reasonable sensing range and sensitivity plus low cost, have rose a huge consumer market and also immense interests in fundamental studies and technological applications, especially in the field of biomimetic robots movement detection and human health condition monitoring. In this paper, we propose a new flexible strain sensor based on thick CVD graphene film and its low-cost fabrication strategy by using the commercial adhesive tape as flexible substrate. The tensile tests in a strain range of ~30% were implemented, and a gage factor of 30 was achieved under high strain condition. The optical microscopic observation with different strains showed the evolution of cracks in graphene film. Together with commonly used platelet overlap theory and percolation network theory for sensor resistance modeling, we established an overlap destructive resistance model to analyze the sensing mechanism of our devices, which fitted the experimental data very well. The finding of difference of fitting parameters in small and large strain ranges revealed the multiple stage feature of graphene crack evolution. The resistance fallback phenomenon due to the viscoelasticity of flexible substrate was analyzed. Our flexible strain sensor with low cost and simple fabrication process exhibits great potential for commercial applications.

• Journal of Microbiology and Biotechnology
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• v.29 no.2
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• pp.274-282
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• 2019

Mercury-resistant ($Hg^R$) bacteria were isolated from heavy metal polluted wastewater and soil collected near to tanneries of district Kasur, Pakistan. Bacterial isolates AZ-1, AZ-2 and AZ-3 showed resistance up to $40{\mu}g/ml$ against mercuric chloride ($HgCl_2$). 16S rDNA ribotyping and phylogenetic analysis were performed for the characterization of selected isolates as Bacillus sp. AZ-1 (KT270477), Bacillus cereus AZ-2 (KT270478) and Bacillus cereus AZ-3 (KT270479). Phylogenetic relationship on the basis of merA nucleotide sequence confirmed 51-100% homology with the corresponding region of the merA gene of already reported mercury-resistant Gram-positive bacteria. The merE gene involved in the transportation of elemental mercury ($Hg^0$) via cell membrane was cloned for the first time into pHLV vector and transformed in overexpressed C43(DE3) E. coli cells. The recombinant plasmid (pHLMerE) was expressed and the native MerE protein was obtained after thrombin cleavage by size exclusion chromatography (SEC). The purification of fusion/recombinant and native protein MerE by Ni-NTA column, dialysis and fast protein liquid chromatography (FPLC/SEC) involved unfolding/refolding techniques. A small-scale reservoir of wastewater containing $30{\mu}g/ml$ of $HgCl_2$ was designed to check the detoxification ability of selected strains. It resulted in 83% detoxification of mercury by B. cereus AZ-2 and B. cereus AZ-3, and 76% detoxification by Bacillus sp. AZ-1 respectively (p < 0.05).

• Korean Journal of Agricultural Science
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• v.48 no.1
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• pp.21-31
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• 2021

Yeast strains are capable of hydrolyzing non-digestible saccharides, such as melibiose, raffinose, and stachyose, found in soy meal components. This study revealed the biochemical properties of fermented soybean meal during 72 hours with kefir. Starchyose and raffinose, non-digestible components, were almost digested in kefir 150 mL + soybean meal 500 g + water 70 mL and galactose was produced. Proteolysis of the soybean meal produced most of the small molecule peptides in kefir 150 mL + soybean meal 500 g + water 70 mL. The production of the vitamin B group and C were the highest in kefir 250 mL + soybean meal 500 g. The yeast number of the fermented soybean meal was 7.0 × 10⁶ CFU·mL^-1 which was the highest in kefir 250 mL + soybean meal 500 g. The lactic acid bacteria of the fermented soybean meal was the highest at 3.5 × 10⁹ CFU·mL^-1 in kefir 70 mL + soybean meal 500 g. The antioxidant effect was the highest at 57% in kefir 250 mL + soybean meal 500 g. Expression of inflammation-related cytokine (interleukin [IL]-1β, tumor necrosis factor [TNF]-α, and interleukin [IL]-6) was significantly inhibited in fermented soybean meals with different treatments. These results suggest that fermented soybean meal by kefir has an antiinflammatory and anti-oxidation activity and could be utilized in feed manufacturing, and inhydrolyzing non-digestible soy meal components.

• The Plant Pathology Journal
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• v.38 no.6
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• pp.679-684
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• 2022

Rice blast is one of the most destructive diseases of rice worldwide, and the causative agent is the filamentous ascomycete Magnaporthe oryzae. With the successful cloning of more and more avirulence genes from M. oryzae, the direct extraction of M. oryzae genomic DNA from infected rice tissue would be useful alternative for rapid monitoring of changes of avirulence genes without isolation and cultivation of the pathogen. In this study, a fast, low-cost and reliable method for DNA preparation of M. oryzae from a small piece of infected single rice leaf or neck lesion was established. This single step method only required 10 min for DNA preparation and conventional chemical reagents commonly found in the laboratory. The AvrPik and AvrPi9 genes were successfully amplified with the prepared DNA. The expected DNA fragments from 570 bp to 1,139 bp could be amplified even three months after DNA preparation. This method was also suitable for DNA preparation from M. oryzae strains stored on the filter paper. All together these results indicate that the DNA preparation method established in this study is reliable, and could meet the basic needs for polymerase chain reaction-based analysis of M. oryzae.

• Journal of Animal Science and Technology
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• v.64 no.2
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• pp.343-352
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• 2022

Pig slaughterhouses harbor high humidity because of the necessary cleaning that takes place simultaneously with slaughter, which facilitates the existence of mold. Due to the enclosed space, there are several limitations to the control of mold growth with respect to cleaning, ventilation, and drying. In this study, the prevalence of fungi was investigated in four pig slaughterhouses in Korea. Four fungi (Aspergillus niger, Penicillium commune, Penicillium oxalicum, and Cladosporium cladosporioides) were detected with the highest frequency. These four strains were subjected to various treatments to reduce their growth. The fungi were inoculated onto stainless steel (SS) chips and treated with ultraviolet (UV)-C irradiation and hot water. Individual treatments with UV-C (15, 30, 90, 150, 300, and 600 mJ/cm²), and hot water (60, 65, 70, and 83℃) were performed to sanitize the SS chips. Simultaneous cleaning with 60℃ hot water and more than 150 mJ/cm² of UV-C reduced the fungal incidence by > 6.5 Log from 6.6-7.0 Log CFU/cm² (initial count). Our results demonstrate that a combined treatment of UV-C and hot water is the most economical and convenient way to prevent microbiological contamination of small tools (such as knives and sharpeners) and steel surfaces in slaughterhouses.