In the seismic design of building structural members, due to the complexity of the placement of PC steels in prestressed concrete members, it is necessary to review and define the definition of member damage in comparison with reinforced concrete members.In this study, the results of past experiments compared with the calculation results by ‘section Analysis Method’, with the aim of reviewing the precision of calculation results when member damage evaluation is performed using the section analysis method. Furthermore, it is also compared with the calculation results by the ‘split Element Method’.In addition, parametric studies were carried out, and the influence of the difference between the amount of PC steels and reinforced bar on the residual strain was examined.

We developed single nucleotide polymorphism (SNP) markers and are establishing diagnostic systems to distinguish disease resistance- and susceptible-strains of honey bees using the SNPs. For development of SNP markers, whole genome was sequenced each from 20 individuals of “disease resistance-strain” and “susceptible-strain” of Apis mellifera ligustica using the Illumina HiSeq 2000 sequencer. Approximately, 344 and 294 million sequence reads were mapped to the honeybee reference assembly (Amel_4.5) for each strain, respectively. Among the total 2,246,428 SNPs yielded, 33 were found to be fixed between the two strains with all homozygosity. Sixteen of them were casually amplified and sequenced from randomly selected each 10 individual of honey bees from each strain and presented strain specific SNPs. These ten SNPs were used to diagnose the two strains either by original size difference, caused by indel-accompanying SNP, typical PCR-RFLP, or AS PCR.

Ryanodine receptors (RyRs) regulate the contractions of insect muscles by altering intracellular Ca2+ concentration and are the targets of chlorantraniliprole. Here we established two resistant strains of Drosophila melanogaster, which were treated with low or high concentrations of chlorantraniliprole, and their resistance levels were determined on the basis of contact and ingestion toxicities. Compared with the wild type, the two resistant strains did not show any significant differences in contact toxicity. However, they showed significantly increased resistance ratios in ingestion toxicity than that by the wild type. The resistant strains had altered expression levels of RyRs and more enhanced Acetylcholinesterase and Glutathione-S-transferase activities than that by the non-selected strain. These results suggested that the resistance development of chlorantraniliprole in the two strains might be mediated by the activation of detoxification pathways in D. melanogaster.

PURPOSES: This study is primarily focused on evaluating the effects of the non-linear stress-strain behavior of RAP concrete on structural response characteristics as is applicable to concrete pavement. METHODS : A 3D FE model was developed by incorporating the actual stress-strain behavior of RAP concrete obtained via flexural strength testing as a material property model to evaluate the effects of the non-linear stress-strain behavior to failure on the maximum stresses in the concrete slab and potential performance prediction results. In addition, a typical linear elastic model was employed to analyze the structural responses for comparison purposes. The analytical results from the FE model incorporating the actual stress-strain behavior of RAP concrete were compared to the corresponding results from the linear elastic FE model. RESULTS : The results indicate that the linear elastic model tends to yield higher predicted maximum stresses in the concrete as compared to those obtained via the actual stress-strain model. Consequently, these higher predicted stresses lead to a difference in potential performance of the concrete pavement containing RAP. CONCLUSIONS : Analysis of the concrete pavement containing RAP demonstrated that an appropriate analytical model using the actual stress-strain characteristics should be employed to calculate the structural responses of RAP concrete pavement instead of simply assuming the concrete to be a linear elastic material.

This paper is concerned with a test method that can be used to investigate the parameters of the Johnson-Cook constitutive model. These parameters are essential for accurately analyzing material behavior under impact loading conditions in numerical simulation. Ti-6Al-4V alloy (HCP crytal structure) was used as a specimen for the experiments. In the 10−3-103/ s strain rate range, three types of experimental methods (convention, compression and tension) were employed to compare the differences using MTS-810, SHPB and SHTB. Finite element analysis results when applying these parameters were displayed along with the experiment results.

Due to a lack of the hoop action of lateral reinforcements the effective confining force in rectangular sections reduces compared to circular ones. Therefore, the stress-strain model obtained from the experimental data with circular sections overestimates the lateral confinement effect in rectangular sections, which evaluates seismic safety margin of overall structural system excessively. In this study experiments with laterally-confined square sections have been performed and the characteristic values composing stress-strain model have been analyzed. With introduction of section coefficients, in addition, the new unified stress-strain model applicable to square sections as well as circular ones has been proposed.

In order to avoid collapse of bridges in earthquakes bridge piers are generally designed to attain sufficient ductility. This full-ductility design method has merits for securing the seismic safety readily against strong earthquakes but, it has weakness of high cost design because of excessive safety margin. Recently, in many countries with high seismic technologies, the seismic design concept tends to shift from the collapse prevention design to the performance-based one which requires different performance (damage) levels according to the structural importance. In order to establish this performance-based design method the displacement ductility of confined concrete members should be evaluated quantitatively. And the stress-strain model of confined concrete is indispensible in evaluating displacement ductility. In this study, 6 test groups with different lateral reinforcement ratios were prepared. 10 same specimens with circular section for each group were tested to obtain more reliable test results. The characteristic values necessary for composing the stress-strain model were obtained from experiments. Based on these characteristic values the new stress-strain model modifying the Hoshikuma's one has been proposed.

One of the issues currently facing nuclear power plants is how to store spent nuclear waste materials which are contaminated with radionuclides such as 134Cs, 135Cs, and 137Cs. Bioremediation processes may offer a potent method of cleaning up radioactive cesium. However, there have only been limited reports on Cs+ tolerant bacteria. In this study, we report the isolation and identification of Cs+ tolerant bacteria in environmental soil and sediment. The resistant Cs+ isolates were screened from enrichment cultures in R2A medium supplemented with 100 mM CsCl for 72 h, followed by microbial community analysis based on sequencing analysis from 16S rRNA gene clone libraries (NCBI’s BlastN). The dominant Bacillus anthracis Roh-1 and B. cereus Roh-2 were successfully isolated from the cesium enrichment culture. Importantly, B. cereus Roh- 2 is resistant to 30% more Cs+ than is B. anthracis Roh-1 when treated with 50 mM CsCl. Growth experiments clearly demonstrated that the isolate had a higher tolerance to Cs+. In addition, we investigated the adsorption of 0.2 mg L-1 Cs+ using B. anthracis Roh-1. The maximum Cs+ biosorption capacity of B. anthracis Roh-1 was 2.01 mg g-1 at pH 10. Thus, we show that Cs+ tolerant bacterial isolates could be used for bioremediation of contaminated environments.

기능성 발효유로 알려진 케피어로부터 박테리오신 생산 유산균주(CJNU 2008)를 선발하였다. CJNU 2008 균주는 16S rRNA 유전자 염기서열 분석을 통해 Enterococcus faecium으로 동정되어 E. faecium CJNU 2008로 명명하였다. E. faecium CJNU 2008균주의 배양액 및 부분정제 농축액은 Listeria monocytogenes와 Staphylococcus aureus와 같은 병원성 세균을 포함하여 몇몇 균주들에 대해서 항균활성을 나타내었다. E. faecium CJNU 2008 균주의 박테리오신 생산을 위한 배양 최적조건은 MRS broth, 30℃ 및 pH 7.0으로 확인되었다.

Cordyceps species are important mushrooms traditionally used for heaths and vitality. C. sinensis has been widely used as a medicinal mushroom and C. militaris is popular for its substitute. C. militaris can be cultivated artificially and new strains has been improved by crossing single spore strains. As a bipolar heterothallic fungus C. militaris has two strains of compatible mating types and they can be differentiated by crossing, fruiting body formation ability and the production of perithecia. However this process is very laborious and time consuming to carry out. In this study, molecular markers were designed and used for the detection of two opposite mating types. Two mating types were assayed using two sets of primers specific for C. militaris, which were amplified a 191-bp fragment for MAT1-2 and 233-bp fragment for MAT1-1. After crossing of two compatible mating types F1 hybrids resulted in well-developed perithecial fruiting bodies and their crossings were confirmed by the multiplex PCR assays for the rapid and specific detection of both MAT1-1 and MAT1-2. This results may serve as a efficient process in the breeding program for artificial cultivation and industrial-scale production of C. militaris.

The present study deals with the effects of micro-alloying elements such as Ni, V, and Ti on the recrystallization behavior of carbon steels at different strain rates. Eight steel specimens were fabricated by varying the chemical composition and reheating temperature; then, a high-temperature compressive deformation test was conducted in order to investigate the relationship of the microstructure and the recrystallization behavior. The specimens containing micro-alloying elements had smaller prior austenite grain sizes than those of the other specimens, presumably due to the pinning effect of the formation of carbonitrides and AlN precipitates at the austenite grain boundaries. The high-temperature compressive deformation test results indicate that dynamic recrystallization behavior was suppressed in the specimens with micro-alloying elements, particularly at increased strain rate, because of the pinning effect of precipitates, grain boundary dragging and lattice misfit effects of solute atoms, although the strength increased with increasing strain rate.

In the present study, the tensile properties and dynamic strain aging of an Fe-24.5Mn-4Cr-0.45C alloy were investigated in terms of strain rate. During tensile testing at room temperature, all the stress-strain curves exhibited serrated plastic flows related to dynamic strain aging, regardless of the strain rate. Serration appeared right after yield stress at lower strain rates, while it was hardly observed at high strain rates. On the other hand, strain-rate sensitivity, indicating a general relationship between flow stress and strain rate at constant strain and temperature, changed from positive to negative as the strain increased. The negative strain-rate sensitivity can be explained by the Portevin Le Chatelier effect, which is associated with dynamic strain aging and is dependent on the strain rate because it is very likely that the dynamic strain aging phenomenon in high-manganese steels is involved in the interaction between moving dislocations and point-defect complexes.

Dextran is a generic term for a bacterial exopolysaccharide synthesized from sucrose and composed of chains of D-glucose units connected by α-1,6-linkages by using dextransucrases. Dextran could be used as vicosifying, stabilizing, emulsifying, gelling, bulking, dietary fiber, prebiotics, and water holding agents. We isolated new strain capable of producing dextran from Korean traditional kimchi and identified as Leuconostoc sp. strain JYY4. Batch fermentation was conducted in bioreactor with a working volume of 3 L. The media was MMY and 15% (w/v) sucrose. Mineral medium consisted of 3.0 g KH2PO4, 0.01 g FeSO4, H2O, 0.01 g MnSO4, 4H2O, 0.2 g MgSO4 7H2O, 0.01 g NaCl, 0.05 g CaCl2 per 1 liter deionized water. The pH of media was initially adjusted to 6.0. The inoculation rate was 1.0% (v/v) of the working volume. Temperature was maintained at 28oC. The agitation rate was 100 rpm. The production pattern of dextran was associated with the cell growth. After 24 hr dextran reached its highest concentration of 59.4 g/L. The sucrose was consumed completely after 40 hr. Growth reached stationery phase when sucrose became limiting, regardless of the presence of fructose or mannitol. When the specific growth rate was 0.54 hr-1, utilization averaged 5.8 g/L-hr. The yield and productivity of dextran were 80% and 2.0 g/L-hr, respectively. Dextrans produced by were separated to two different size by an alcohol fraction method. The size of high molecular weight dextran (45% alcohol, v/v), less soluble dextran, was between MW 500,000 and 2,000,000. Soluble dextran (55% alcohol, v/v) was between 70,000 and 150,000. The molecular weight average of total dextran (70% alcohol, v/v) was between 150,000 to 500,000. The enzymatic hydrolyzates of total dextran of ATCC 13146 showed branched dextrans by Penicillium dextranase contained of glucose, isomaltose, isomaltotriose, and isomaltooligosaccharides greater than DP4 (degree of polymerization) that had branch points. Compounds greater than DP4 were branched isomaltooligosaacharides. Hydrolysates by the Lipomyces dextranase produced the same composition of oligosaccharides as those by Penicillin dextranase.

KO mice provide an excellent tool to determine roles of specific genes in biomedical filed. Traditionally, knockout mice were generated by homologous recombination in embryonic stem cells. Recently, engineered nucleases, such as zinc finger nuclease, transcription activator-like effector nuclease and clustered regularly interspaced short palindromic repeats (CRISPR), were used to produce knockout mice. This new technology is useful because of high efficiency and ability to generate biallelic mutation in founder mice. Until now, most of knockout mice produced using engineered nucleases were C57BL/6 strain. In the present study we used CRISPR-Cas9 system to generate knockout mice in FVB strain. We designed and synthesized single guide RNA (sgRNA) of CRISPR system for targeting gene, Abtb2. Mouse zygote were obtained from superovulated FVB female mice at 8-10 weeks of age. The sgRNA was injected into pronuclear of the mouse zygote with recombinant Cas9 protein. The microinjected zygotes were cultured for an additional day and only cleaved embryos were selected. The selected embryos were surgically transferred to oviduct of surrogate mother and offsprings were obtained. Genomic DNA were isolated from the offsprings and the target sequence was amplified using PCR. In T7E1 assay, 46.7% among the offsprings were founded as mutants. The PCR products were purified and sequences were analyzed. Most of the mutations were founded as deletion of few sequences at the target site, however, not identical among the each offspring. In conclusion, we found that CRISPR system is very efficient to generate knockout mice in FVB strain.

Bi0.5Na0.5TiO3 (BNT) based ceramics are considered potential lead-free alternatives for Pb(Zr,Ti)O3(PZT) based ceramics in various applications such as sensors, actuators and transducers. However, BNT-based ceramics have lower electromechanical performance as compared with PZT based ceramics. Therefore, in this work, lead-free bulk 0.99[(Bi0.5Na0.5)0.935Ba0.065](1-x)LaxTiO3-0.01SrZO3 (BNBTLax-SZ, with x = 0, 0.01, 0.02) ceramics were synthesized by a conventional solid state reaction The crystal structure, dielectric response, degree of diffuseness and electric-field-induced strain properties were investigated as a function of different La concentrations. All samples were crystallized into a single phase perovskite structure. The temperature dependent dielectric response of La-modified BNBT-SZ ceramics showed lower dielectric response and improved field-induced strain response. The field induced strain increased from 0.17% for pure BNBT-SZ to 0.38 % for 1 mol.% La-modified BNBT-SZ ceramics at an applied electric field of 6 kV/mm. These results show that Lamodified BNBT-SZ ceramic system is expected to be a new candidate material for lead-free electronic devices.

피부의 피부 노화, 질환, 훼손은 내부적인 요인으로서 활성산소라는 사실이 밝혀진 이래로 합 성 항산화제를 대체할 수 있는 천연물 항산화제에 대하여 많은 연구가 진행 중이다. 이들 중에 지실은 오래전부터 만성적인 염증, 알리지 완화, 황산화 기능을 하는 것으로 알려져 왔다. 미생물을 이용한 발 효는 조직에 결합 되어 있는 생리활성 물질의 유리로 생체이용율(bioavailability) 훨씬 높아지는 것으로 알려 졌다. 따라서 본 연구는 지실 열수 추출물을 기질로 GRAS 알려진 균주를 이용하여 발효를 수행하 고 발효가 항산화 능력에 미치는 영향에 대하여 알아보고자하였다. 지실 열수 추출물은 항산화 기능을 가지고 있는 hesperidine, naringine, luteoilin, imperatorin등의 플라보노이드 및 furocoumarin등이 동정 이 되었고 함유량은 hesperidine naringine, imperatorin, luteolin 순이었다. 열수 추출물을 기질로 하여 분리된 Leuconostocs sp. strain JYK로 발효를 수행한 결과 지실 열수 추출물을 사용한 경우에는 71.2±4.58 (mg/g)의 총 페놀 함량이 있는 것으로 측정이 되었고 반면에 발효 추출물에는 89.2±13.47 (mg/g)으로 약 25.3% 증가된 것으로 나타났다. 총 플라보노이드 화합물은 지실 열수 추출물에는 25.1±4.12 (mg/g)의 총 플라보노이드 함량이 있는 것으로 측정이 되었고 반면에 발효 추출물에는 31.0±4.06 (mg/g)으로 약 23.5% 증가된 것으로 나타났다. DPPH 소거능은 지실 열수 추출물에는 70.9% 반면에 발효 추출물은 86.2% 측정이 되었다. 총 항산화 능력은 18.7% 발효추출은 26.6%로 발 효를 통하여 약 40% 증가하였다. 따라서 미생물 발효를 통하여 천연물에 포함이 되어있는 기능성 물질 에 대한 생체 이용률을 높인다면 산화적 스트레스에 의한 피부 노화 완화 및 개선 작용으로 기능성 화 장품 및 식품의 소재로 활용 가치를 높여 줄 것으로 기대를 한다.

A new commercial strain “Mongdol” of oyster mushroom was developed by hyphal anastomosis. It was improvedwith hybridization between monokaryotic strain derived from Pleurotus ostreatus ASI 0627 and dikaryotic strain derived from P.ostreatus ASI 2929. The optimum temperature of mycelial growth and fruiting body development were 25~30oC and 12~18oC,respectively. When two different media including PDA (potato dextrose agar medium) and MCM (mushroom complete medium)were compared, the mycelial growth of this mushroom was faster in MCM than in PDA. Similar result was observed with thecontrol strain P. ostreatus ASI 2504. Analysis of the genetic characteristics of the new cultivar “Mongdol” showed a different DNAprofile as that of the control strain ASI 2504, when RAPD (Random Amplified Polymorphic DNA) primer URP3 and URP6 wereused. Fruiting body production per bottle was about 106 g using demonstration farms. The color of pileus was blackish gray andthe stipe was long. Therefore, we expect that this new strain “Mongdol” will satisfy the consumer’s demand for high qualitymushrooms.

In-situ neutron diffraction has been employed to examine the effect of strain path on lattice strain evolution during monotonic and cyclic tension in an extruded Mg-8.5wt.%Al alloy. In the cyclic tension test, the maximum applied stress increased with cycle number. Lattice strain data were acquired for three grain orientations, characterized by the plane normal to the stress axis. The lattice strain in the hard {10.0} orientation, which is unfavorably oriented for both basal slip and {10.2} extension twinning, evolved linearly throughout both tests during loading and unloading. The {00.2} orientation exhibited significant relaxation associated with {10.2} extension twinning. Coupled with a linear lattice strain unloading behavior, this relaxation led to increasingly compressive residual strains in the {00.2} orientation with increasing cycle number. The {10.1} orientation is favorably oriented for basal slip, and thus showed a soft grain behavior. Microyielding occurred in the monotonic tension test and in all cycles of the cyclic test at an applied stress of ~50 MPa, indicating that strain hardening in this orientation was not completely stable from one cycle to the next. The lattice strain unloading behavior was linear in the {10.1} orientation, leading to a compressive residual strain after every cycle, which, however, did not increase systematically from one cycle to the next as in the {00.2} orientation.