• Journal of Life Science
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• v.9 no.1
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• pp.14-16
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• 1999

Genetic variability was monitored by random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) in dicofol-susceptible (S), dicofol-resistant (R) and its reverse-selected (RS) strains of two-spotted spider mite, of Tetranychus urticae. Before the reverse-selection, RS strain, selected reversely from R strain, was 23-fold resistance ratio at {TEX}$LC_{50}${/TEX} to S strain. The resistance was started to in incline slowly to the resistance level of S strain after one year, and the resistance ratio was 4-fold in the 7 years after then. PCR-amplification of T. urticae DNA showed polymorphism in the amplifications with 12 primers in 100 kinds of arbitrary DNA sequences. RAPD amplification with primer OPR-12 (5`-ACAGGTGCGT-3`) showed amplified bands at 1,000 base pair in the S-and RS-strain, and at 350 base pair in R-strain. The results of polymorphism are genetic variabilities derived from development and selection of resistance in each strain. The peculiarly amplified fragments were guessed to participate in dicofol resistance. From the analysis of genetic similarity, it is inferred the gene composition of S-and RS-strain is much closer than that of R-strain.

• Geomechanics and Engineering
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• v.20 no.2
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• pp.121-129
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• 2020

In the design of geotechnical structures, engineers choose either peak or critical state friction angles. Unfortunately, this selection is based on engineer's preference for economy or safety and lacks the assessment of the expected level of deformation. To fill this gap in the design process, this study proposes a strain based empirical method. Proposed method is founded on the experimentally supported assumption that higher dilatancy angles result in more brittle soil response. Using numerous triaxial test data on ten different soils, an empirical design chart is developed that allows the estimation of shear strain at failure based on soil's peak dilatancy angle and mean grain diameter. Developed empirical chart is verified by conducting a small scale retaining wall physical model test. Finally, a design methodology is proposed that makes the selection of design friction angle in structured way possible based on the serviceability limits of the proposed structure.

• Mycobiology
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• v.40 no.2
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• pp.111-116
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• 2012

Ten strains of the entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana were evaluated to find the most effective strain for optimization studies. The first criterion tested for strain selection was the mortality (> 50%) of Spodoptera litura larvae after inoculation of the fungus for 4 days. Results on several bioassays revealed that B. bassiana BNBCRC showed the most virulence on mortality S. litura larvae (80% mortality). B. bassiana BNBCRC also showed the highest germination rate (72.22%). However, its conidia yield ($7.2{\times}10^8$ conidia/mL) was lower than those of B. bassiana B 14841 ($8.3{\times}10^8$ conidia/mL) and M. anisopliae M6 ($8.2{\times}10^8$ conidia/mL). The highest accumulative radial growth was obtained from the strain B14841 (37.10 mm/day) while the strain BNBCRC showed moderate radial growth (24.40 mm/day). M. anisopliae M6 possessed the highest protease activity (145.00 mU/mL) while M. anisopliae M8 possessed the highest chitinase activity (20.00 mU/mL) during 96~144 hr cultivation. Amongst these criteria, selection based on virulence and germination rate lead to the selection of B. bassiana BNBCRC. B. bassiana B14841 would be selected if based on growth rate while M. anisopliae M6 and M8 possessed the highest enzyme activities.

• Journal of Sericultural and Entomological Science
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• v.37 no.1
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• pp.27-32
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• 1995

Studies were carried out to report breeding procedure and characteristics of Fb, a strain of silkworm with abnormal food habit polyphagous. Selection was continued up to the 14th generation toward higher incidence of cabbage leaves feeding variants. In the autumn of 1992(7th generation), selected strain were subjected to severe selection by feeding them on artificial diet that did not contain mulberry leaf powder. The results were clearly positive and reached to higher than 95% of cabbage feeding in the 14th generation. This strain was first discovered by feeding cabbage leaves, but later they were observed to eat some kind of plants like lettuce, Chinese cabbage, radish, beet, apple, persimmon, pear, etc. As described above the procedure, cabbage feeding trait was clearly heritable. The strain responsible for this traits was named Fb.

• International Journal of Industrial Entomology and Biomaterials
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• v.10 no.2
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• pp.95-99
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• 2005

A breeding plan was carried out on four commercial strains of silkworm (Bombyx mori L.) 101, 102, 103 and 104 to improve some important traits. Genetic gain or response to selection $({\Delta}G)$, heritability of cocoon shell weight (CSW) and specific combining ability effects were estimated to determine the strains that can be improved. Strain 101 had lowest heritabitity, ${\Delta}G$ and viability. Strain 102 was acceptable in selection response but its viability was low. Therefore these two strains were not suitable for more selection. As a result, only lines 103 and 104 were chosen for further improvement. Intra population selection based on independent culling level method practiced from third to sixth generation for both productive and viability traits simultaneously. While CSW and CW had increasingly enhanced during primary generations, they went slightly up after third generation. According to negative genetic correlation, viability decreased during primary generations, but after third generation that paid attention to balanced development of both productive and viability traits, viability increased so that the pupation rate reached to $91\%$ in 103 and $97\%$ in 104 for last generation $(G_8)$.

• Microbiology and Biotechnology Letters
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• v.19 no.4
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• pp.343-347
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• 1991

An improved method for the selection of high tobramycin-producing mutants of Streptomyces tenebrarius ATCC 17920 was investigated. By the use of apramycin-containing media, low nebramycin-producing mutants were eliminated. Strain No. 23, resistant to apramycin and kanamycin B and sensitive to tobramycin, was isolated from soils, identified as Pseudomonas paucimobilis and used as a test organism for overlaying the mutants on agar plate. While inhibition zones were not shown when the parent strains were overlaid with soft agar containing the strain No. 23, clear zones were shown when high tobramycin-producing mutants were overlaid. Using this screening strategy, 58 mutants showing clear zones had been isolated. antibiotic activities of which were incresed to 3~8 fold compared to that of parent strain.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11a
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• pp.345.2-345
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• 2002

This paper focuses on the formulation and validation of an automatic strategy for the selection of the locations and directions of strain gauges to capture at best the modal response of a blade in a series of modes. These locations and directions are selected to render the strain measurements as robust as possible with respect to random mispositioning of the gauges and gauge failures. (omitted)

• Microbiology and Biotechnology Letters
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• v.32 no.4
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• pp.356-361
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• 2004

The ethionine resisconferring gene (ERCI) was constitutively expressed under the control of the alcohol dehydrogenase gene promoter (ADClp) and introduced into the chromosomes of an industrial polyploid strain of Saccharocerevisiae by using the 8-sequences of the Tyl retrotransposon as the recombination site. 8-Integrative cassette devoid of bacterial DNA sequences containing the ampicillin resistance gene was constructed that had the aureobasidin A resistance gene (AURl-C) as the selection marker and ERCl gene. The ERCl gene was also employed as the selection marker in the 8-integrative cassette lacking the A URl-C gene. Industrial Saccerevisiae transformed with these integrative cassettes exhibited strong resistance to DL-ethioncompared with nontransformants.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.22 no.4
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• pp.349-354
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• 2009

To rationally secure and maintain the safety and serviceability of a high-rise building, monitoring of structural responses of members is necessary. As such health monitoring of large-scale building structures has received growing attention by researchers in recent years. However, due to a very large number of members complexity of structural responses of a high-rise building structure, practical difficulties exist in selection of structural members to be sensored for assessment of structural safety of a structure. In this paper, a selection technique for active members for safety monitoring of a high-rise building based on displacement participation factor and strain energy density of a member is investigated.

• Mycobiology
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• v.38 no.3
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• pp.210-214
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• 2010

Selection of fungal strains with high virulence against the developmental stages of Bemisia tabaci was performed using internal transcribed spacer regions. The growth rate of hyphae was measured and bioassay of each developmental stage of B. tabaci was conducted for seven days. All of the fungal strains tested were identified as Lecanicillium spp., with strain 4078 showing the fastest mycelium growth rate (colony diameter, 16.3 $\pm$ 0.9 mm) among the strains. Compared to strain 4075, which showed the slowest growth rate, the growth rate of strain 4078 was increased almost 2-fold after seven days. Strains 4078 and Btab01 were most virulent against the egg and larva stages, respectively. The virulence of fungal strains against the adult stage was high, except for strains 41185 and 3387. Based on the growth rate of mycelium and level of virulence, strains 4078 and Btab01 were selected as the best fungal strains for application to B. tabaci, regardless of developmental stage.