• Mycobiology
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• v.34 no.3
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• pp.131-137
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• 2006

In vitro fruiting bodies were produced from ten different isolates of Condyceps militaris EFCC C-5736, EFCC C-5941, EFCC C-5976, EFCC C-6040, EFCC C-6849, EFCC C-7268, EFCC C-7342, EFCC C-7992, EFCC C-8027 and EFCC C-8549. Single ascospores were isolated from in vitro grown fruiting bodies and used for fruiting body production in brown rice medium by both intra-strain crossing and out-crossing. Length and dry wt. of stromata grown in vitro were measured. Strains producing highest dry wt. of stromata were selected. Both intra-strain crossings and inter-strain crossings of single ascospore strains were found to produce profuse fruiting bodies of C. militaris.

• Earthquakes and Structures
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• v.7 no.5
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• pp.647-665
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• 2014

Squat reinforced concrete walls require enough shear strength in order to promote flexural yielding, which creates the need for designers of an accurate method for strength prediction. In many cases, especially for existing buildings, strength estimates might be insufficient when more accurate analyses are needed, such as pushover analysis. In this case, estimates of load versus displacement are required for building modeling. A model is developed that predicts the shear load versus shear deformation of squat reinforced concrete walls by means of a panel formulation. In order to provide a simple, design-oriented tool, the formulation considers the wall as a single element, which presents an average strain and stress field for the entire wall. Simple material constitutive laws for concrete and steel are used. The developed models can be divided into two categories: (i) rotating-angle and (ii) fixed-angle models. In the first case, the principal stress/strain direction rotates for each drift increment. This situation is addressed by prescribing the average normal strain of the panel. The formation of a crack, which can be interpreted as a fixed principal strain direction is imposed on the second formulation via calibration of the principal stress/strain direction obtained from the rotating-angle model at a cracking stage. Two alternatives are selected for the cracking point: fcr and 0.5fcr (post-peak). In terms of shear capacity, the model results are compared with an experimental database indicating that the fixed-angle models yield good results. The overall response (load-displacement) is also reasonable well predicted for specimens with diagonal compression failure.

• Elastomers and Composites
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• v.39 no.1
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• pp.23-35
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• 2004

In this work, effects of hyper-elastic rubber material properties on the indentation load-deflection curve and subindenter deformation are first examined via finite element (FE) analyses. An optimal data acquisition spot is selected, which features maximum strain energy density and negligible frictional effect. We then contrive two normalized functions, which map an indentation load vs. deflection curve into a strain energy density vs. first invariant curve. From the strain energy density vs. first invariant curve, we can extract the rubber material properties. This new spherical indentation approach produces the rubber material properties in a manner more effective than the common uniaxial tensile/compression tests. The indentation approach successfully measures the rubber material properties and the corresponding nominal stress-strain curve.

• Magazine of the Korea Concrete Institute
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• v.8 no.2
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• pp.119-127
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• 1996

Objection of this study is to present the three-dimensional material nonlinear analysis of reinforced concrete. A concrete is idealized with three-dimensional 16-node solid element including triaxial nonlinear stress-strain behavior, cracking, crushing and strain softening: a steel with three-dimensional 3 node truss element including elastic-plastic behavior with strain hardening. The cracked shear retention factor is introduced to estimate the effective shear modulus con sidering aggregate interlock after c:racking and a modified newton method is used to obtain a nu merical solution. Numerical results in a gauss point is displayed graphically. Numerical examples of Krahl's reinforced concrete beam and Hedgreds shell are selected to compare with the experimental and numerical results.

• Journal of Microbiology and Biotechnology
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• v.16 no.4
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• pp.531-537
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• 2006

Lactic acid-producing bacteria (LABs) are known to have various beneficial properties for health. However, they are generally considered to have an adverse effect on teeth, since they produce acid. Nonetheless, milk and cheese containing specific LAB strains were recently found to have an inhibitory effect on dental caries in children, with an inhibitory activity towards the growth of Streptococcus mutans suggested as the responsible mechanism. Accordingly, the current study selected a probiotic candidate for oral health and studied its inhibitory mechanism against dental caries. Twenty-two LAB species belonging to eleven genuses were screened for promoting bone nodule formation using direct microscopic examination. Only one isolate, Weissella kimchii strain PL9001, increased the bone nodule formation significantly. The addition of W. kimchii strain PL9001 to bone cells prepared from mouse calvaria increased the bone nodule formation, calcium accumulation, and activity of alkaline phosphatase (the osteoblastic marker). Moreover, W. kimchii strain PL9001 inhibited the invasion of Streptococcus mutans into bone cells, and an organic extract of the culture supernatant of W. kimchii strain PL9001 inhibited the growth of Strep. mutans. Therefore, the results suggest that W. kimchii strain PL9001 can be used as a preventive measure against dental caries. This is the first time that a LAB has been shown to promote bone nodule formation and prevent the invasion of Strep. mutans into bone cells.

• Korean Journal of Veterinary Service
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• v.32 no.1
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• pp.33-41
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• 2009

In order to develop probiotic strain for pigs, Lactobacillus spp. (527 isolates), Streptococcus spp. (95 isolates) and Bifidobacterium spp. (25 isolates) were isolated from the feces of 35 pigs. These isolates were tested through in vitro experiment such as acid tolerance at pH 2.0 (Lactobacillus spp. and Streptococcus spp.) or pH 3.0 (Bifidobacterium spp.), bile tolerance in MRS broth containing 0.3% (w/v) Oxgall, heat resistance at $70^{\circ}C$ and $80^{\circ}C$ for 5 min, antibiotic resistance, antimicrobial activity against pathogenic bacteria and Caco-2 cell adherence assay. Finally ten most superior strain (5 Lactobacillus spp. strain, 3 Bifidobacterium spp. strain and 2 Streptococcus spp. strain) were selected as potential candidate for probiotic use in pig industry. It could be used as an alternative to antibiotics in feed additives.

• Geomechanics and Engineering
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• v.29 no.4
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• pp.451-461
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• 2022

The roadways surrounded by rock and coal will lose their stability or even collapse under rock burst. Rock burst mainly involves an evolution of dynamic loading which behaves quite differently from static or quasi-static loading. To compare the dynamic response of coal and rocks with different static strengths, three different rocks and bituminous coal were selected for testing at three different dynamic loadings. It's found that the dynamic compression strength of rocks and bituminous coal is much greater than the static compression strength. The dynamic compression strength and dynamic increase factor of the rocks both increase linearly with the increase of the strain rate, while those of the bituminous coal are irregular due to the characteristics of multi-fracture and heterogeneity. Moreover, the absorbed energy of the rocks and bituminous coal both increase linearly with an increase in the strain rate. And the ratio of absorbed energy to the total energy of bituminous coal is greater than that of rocks. With the increase of dynamic loading, the failure degree of the sample increases, with the increase of the static compressive strength, the damage degree also increases. The static compassion strength of the bituminous coal is lower than that of rocks, so the number of small-scale fragments was the largest after bituminous coal rupture.

• Transactions of Materials Processing
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• v.32 no.1
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• pp.20-27
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• 2023

In this study, the deformation of materials was measured using the video and tracking API of OpenCV. Circular markers attached to the material were selected the region of interests (ROIs). The position of the marker was measured from the area center of the circular marker. The position and displacement of the center point was measured along the image frames. For the verification, tensile tests were conducted. In the tensile test, four circular markers were attached along the longitudinal and transverse directions. The strain was calculated using the distance between markers both in the longitudinal and transverse direction. As a result, the stress-strain curve obtained using machine vision is compared to the stress-strain curve obtained from the DIC results. RMSE values of the strain from the machine vision and DIC were less than 0.005. In addition, as a measurement example, a bending angle and springback measurement according to bending deformation, and a moving position measurement of a punch, a blank holder, and a die by time change were performed. Using the proposed method, the deformation and displacement of the materials were measured precisely and easily.

• Food Science and Preservation
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• v.17 no.2
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• pp.174-181
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• 2010

The yeast strains used for fermentation are known to influence the qualities of wine. We investigated the effects of fermentation using different yeast strains on the properties of wine produced from 'Hayward' kiwifruit (Actinidia deliciosa). The physicochemical characteristics of wine produced using various yeast strains for fermentation were also analyzed. Saccharomyces cerevisiae Gervin No.5 strain (GVN), S. bayanus Lavin strain EC1118 (EC1118), and S. cerevisiae Red star Davis No. 796 (No.796) are commercial dry yeast strains selected for optimization of fermentation. Although the soluble solid contents of samples fermented by all three yeast strains decreased by a similar extent, the levels of alcohol production differed, particularly during the first week of fermentation. Use of the GVN strain resulted in the highest alcohol concentration (13.8%, v/v), whereas fermentation with No.796 and EC1118 strains yielded alcohol contents of 13.0% and 12.5% (both v/v), respectively. Upon sensory evaluation, GVN-fermented wine had a strong taste and bitterness, with high acid and alcohol contents. Wine fermented using No.796 had a chemical profile similar to that of GVN-fermented product, but the taste remained sweet, consistent with the lower alcohol content. EC1118-fermented wine was soft and sweet in taste, high in flavor, and had a low alcohol content. Total phenolic levels and antioxidant activities in wine fermented by EC1118 were significantly higher than in wines prepared using No.796 or GVN. When previously described characteristics were additionally considered, EC1118 was selected as an optimum strain for further study. In conclusion, fermentation of kiwifruit using different yeast strains yielded wines with distinct characteristics. The yeast strain EC1118 had the most desirable properties, and is considered suitable for kiwifruit fermentation. Valuable attributes of wine fermented by this yeast include overall sensory acceptance, an appropriate level of total phenolics, and good antioxidant activity.

• Applied Biological Chemistry
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• v.16 no.2
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• pp.78-84
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• 1973

The strains of 297 yeasts were isolated in TakJoo mashes of 12 breweries not using the cultivated yeast and then brewing test with each yeast were carried out. The strains of 7 yeasts that have high fermentative ability among the isolated strains were selected and identified. The results obtained were as follows: 1) In the brewing test with the isolated yeasts of each brewery, average alcohol percentage of each mash had a little differences as $13.20{\sim}15.20$ percentage. 2) In fermentative lest, the isolated yeasts from the first stage mash and from the second stage mash showed t little differences in the average alcohol percentage of mash. 3) The fermentative test using the isolated yeasts based on TTC stain had at little differences. 4) Among 7 strains selected, strains: Dm-1, Dm-2, Y-1, and T-1 appeared TTC pink yeast; strsins:C-1, C-2 and Gs-1 appeared TTC red one. 5) It was identified that strains: Dm-1, Y-1, C-1, C-2 and T-1 were Sac. cerevisae; the strain Gs-1 were Sac. pretoriencis; strain D-2 were Sac. rouxii.