• Journal of Microbiology and Biotechnology
• /
• 제11권2호
• /
• pp.222-228
• /
• 2001

Vibrio metschnikovii strain RH530 is a non-pathogenic, industrially-important alkaline protease producer which has been isolated from wastewater. In this paper, we report on the transformation of this strain by using the method of electroporation. A field strength of $7.5\;kVcm^{-1}$ and $25\;{\mu}F$, and using a 0.2-cm cuvette, appeared to be the optimal conditions for electroporation of the cells with the recombinant pSBCm plasmid carrying the vapK alkaline protease gene and the ColE1 replicon. Cells were subjected to osmotic shock in order to remove extracelluar DNase, and adding 200 mM of sucrose to electroporation buffer cells showed an increased transformation efficiency. Maximum efficiency of transformation was obtained at an early exponential growth phase. Using all of the conditions mentioned above, we routinely obtained a transformation efficiency of more than $10^4{({\mu}g\;plasmid\;DNA)}^{-1}$. The stability of the plasmid pSBCm in V. metschnikovii RH530 was 25% after 18h of growth (27 generations) in the medium without antibiotic selection. The insertion of the par locus to the pSBCm increased the stability of the plasmid up to 42% without selective pressure. The increase in plasmid stability was accompanied by the increase in the productivity of alkaline protease in the recombinant V. metschnikovii strain RH530. Determining optimal conditions for the transformation of the industrially-important, nonpathogenic Vibrio strain, and the improvement of plasmid stability by introducing the par locus into the high copy number plasmid vector, will allow the development of procedures involved in the genetic manipulation of this strain, particularly for its use in the production of industrial enzymes such as alkaline protease.

• Journal of Microbiology and Biotechnology
• /
• 제1권4호
• /
• pp.274-280
• /
• 1991

Effects of IPTG induction on cell growth and production of ${\beta}$-galactosidase-preS2 fusion protein (${\beta}$gal-preS2) were studied in a defined medium using a recombinant Escherichia coli JM109/pCMHB30. IPTG was added (0.2 mM) to induce the cloned-gene expression in the early-, mid-, and late-log growth phases. The most serious decreases in growth rate and plasmid stability were observed for the induction in the early-log growth phase. The expression level of ${\beta}$gal-preS2 attained by the induction in the mid-log phase was about 0.51 mg fusion protein/mg total cellular protein, which was 2- and 5-fold improvement over the levels obtained with the inductions in the early- and late-log phases. Formation of acidic byproducts including acetate and pyruvate showed different profiles during the fermentation period for each cases of induction; pyruvate was the major byproduct for the induction in the early-log phase while acetate production became more significant for the cases of inductions in the mid- and late-log phases.

• 대한용접접합학회:학술대회논문집
• /
• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
• /
• pp.217-221
• /
• 2002

In the coarse grain HAZ adjacent to the fusion line, most of the TiN particles in conventional Ti added steel are dissolved and austenite grain growth is easily occupied during welding process. To avoid this difficulty, thermal stability of TiN particle is improved by increasing the nitrogen content in steel. In this study, the effect of high nitrogen TiN particle on preventing austenite grain growth in HAZ was investigated. Increased thermal stability of TiN particle is helpful for preventing the austenite grain growth by pinning effect. High nitrogen TiN particle in simulated HAZ were not dissolved even at high temperature such as 1400 C and prevented the austenite grain growth in simulated HAZ. Owing to small austenite grain size in HAZ the width of coarse grain HAZ in high nitrogen TiN steel was decreased to 1/10 of conventional TiN steel. Even high heat input welding, the microstructure of coarse grain HAZ consisted of fine polygonal ferrite and pearlite and toughness of coarse grain HAZ was significantly improved.

• 유통과학연구
• /
• 제17권12호
• /
• pp.23-32
• /
• 2019

Purpose As consumer awareness grows, the importance of CSR becomes even more important for long-term growth. In response to this current trend, the purpose of this study is to analyze the effect of CSR activities on business performance for logistics companies. Research design, data, and methodology - Between CSR activities and growth, there was a generally positive(+) relationships between activities such as donation and volunteerism and the growth of the enterprise. In terms of the relationship between environmental factors and growth, negative results were expressed. In case of profitability, improved welfare for workers has had a positive impact on corporate profitability. Results - With respect to stability, a high proportion of equity capital is not considered to be more active in SCR activities. Significant negative results were given between the minimum factors for entry, transportation, and noise generation factors and the ratio of liabilities, which are representative friction factors in the community. Conclusions - With respect to stability, a high proportion of equity capital is not considered to be more active in SCR activities. Significant negative results were given between the minimum factors for entry, transportation, and noise generation factors and the ratio of liabilities, which are representative friction factors in the community.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2017년도 9th Asian Crop Science Association conference
• /
• pp.221-221
• /
• 2017

This experiment was performed to analyze variation of growth traits of soybean to determine the information of less sensitive traits under different environmental conditions. Sowing was carried out on June 2 each year and the experimental plot was laid out in three replicates by randomized complete block design with thirty soybean varieties which consisted of 19 cultivars for beancurd and soypaste, 8 cultivars for soy-sprout including 1 landrace, and 3 cultivars for cooking with rice including 1 landrace during the period 2014-2015. The weather conditions during the experimental period were quite different with extremely low precipitation and longer sunshine duration in 2015 than 2014. The variation of characteristics related to growth period such as days of growth, days of maturity, days of flowering and the 100-seed weight was less in spite of different environmental conditions. While the variation of the number of pods per plant was high. Considering growth and seed characteristics like the number of pods per plant, the number of seeds per pod and 100-seed weight which are linked directly to the yield, cultivars such as Shingi, Daewonkong, Danbaegkong, and Daepung for beancurd and soypaste, Pungwon, Haepum and Shingang for soy-sprout and Seoritae for cooking with rice were more stable and could be expected to have high yield in Suwon, the south-central part of South Korea. These results could be useful for the selection of breeding resources to develop cultivars with high stability under changeable weather condition.

• Asian-Australasian Journal of Animal Sciences
• /
• 제14권10호
• /
• pp.1444-1449
• /
• 2001

Two feeding trials were conducted to determine the effect of inclusion levels or deletion of vitamin-trace mineral (VM) premixes on growth performance and pork quality in finishing pigs. In exp. 1, a total of ninety-six crossbred pigs $(Landrace\;{\times}\;Yorkshire\;{\times}\;Duroc,\;85.09{\pm}3.12kg)$ were used for a 4-week feeding triaL Treatments were premix supplementation at the level of 50% (Control), 100%, 150%, and 200% of NRC (1998) requirements for vitamins and trace minerals. In exp. 2, a total of one hundred and eight crossbred pigs $(Landrace\;{\times}\;Yorkshire\;{\times}\;Duroc,\;84.76{\pm}0.58kg)$ were used for a 4-week feeding trial. Treatments were premix supplementation at the level of 0% (Control), 200% VM, and 200% vitamin E and Se listed in NRC (1998) requirements. Average daily gain (ADG) and feed/gain (F/G) were the highest at 150% VM addition level (quadratic, p<0.05) among treatments. Dressing percentage and backfat thickness in pigs were not affected by different addition levels of VM premixes. Pork stability in terms of TBARS was linearly (p<0.05) improved as dietary VM premix was increased (exp. 1). ADG, F/G and pork stability (TBARS) were also reduced (p<0.05) when VM premixes were deleted. However, supplementation of vitamin E and Se improved (p<0.05) ADG and pork stability when pigs were fed diets without VM premixes (exp. 2). In conclusion, deleting dietary VM premixes gave negative effects on growth performance and pork quality for the last 4 weeks of finishing period.

• 유기물자원화
• /
• 제10권3호
• /
• pp.85-91
• /
• 2002

이 연구는 농 축 수산업으로부터 발생되는 유기성 폐기물의 재활용을 모색하여 농업적 활용방안 가능성을 조사하기 위하여 고속발효 퇴비비활를 통한 퇴비를 공시 재료로하여 그에 대한 안정성 평가와 작물에 대한 생육조사를 진단 하였다. G.I 실험에서는 상추는 모두 발아되지 않았으나 무 종자는 내엽성을 갖아 부분적으로 발아가 되었다. Shince와 TM-1이 각각 61%, 55%의 발아율을 보였고, 전체적으로 뿌리의 생장은 없었다. 퇴비의 안정성 및 비효평가는 TM-1을 제외한 모든 처리구에서, 초기에는 다소 생육이 좋았으나 생육시기가 지날수록 결과는 반대적으로 감소하였다. 따라서 퇴비의 안정성 및 비효평가는, 상추의 초기 생육은 1.5ton/10a 처리가 적당하다고 판단되며, 후기의 단계에서는 3ton/10a가 적절하다 생각된다. 그러나 지속적인 실험과 작물별 특성실험을 통하여 보다 검토가 요구된다.

• Journal of Mechanical Science and Technology
• /
• 제20권9호
• /
• pp.1428-1435
• /
• 2006

A slightly curved crack with an eigenstrain is considered. Solutions for a slightly curved crack in a linear isotropic material under asymptotic loading as well as for a slightly curved crack in a linear isotropic material with a concentrated force are obtained from perturbation analyses, which are accurate to the first order of the parameter representing the non-straightness. Stress intensity factors for a slightly curved crack with an eigenstrain are obtained from the perturbation solutions by using a body force analogy. Particular attention is given to the crack path stability under mode I loading. A new parameter of crack path stability is proposed for a crack with an eigenstrain. The path stability of a crack with steady state growth in a transforming material and a ferroelectric material is examined.

• 폴리머
• /
• 제39권1호
• /
• pp.1-5
• /
• 2015

The effects of zeolite on the thermal stability of poly(vinyl chloride) (PVC) were investigated by the static thermal stability test, pyrolysis experiment and ultraviolet spectrum. The results showed that the porous zeolite could absorb hydrogen chloride (HCl), which suppressed the catalysis of HCl on thermal degradation of PVC, thus improved the thermal stability of PVC. The oxidizing acid which was loaded on zeolite had oxidated on the double bond that formed during the dehydrochlorination of PVC. This process could prohibit the growth of the conjugated polyene and improved the color of PVC. Hence, zeolite might be possible to come up with a high performance thermal stabilizer.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2010년도 추계 학술발표회
• /
• pp.782-789
• /
• 2010

Landslides cause enormous economic losses and casualties. Korea has mountainous regions and heavy slopes in most parts of the land and has consistently built new roads and large-scale housing complexes according to its industrial and urban growth. As a result, the damage from landslides becomes greater every year. In this study, performed a GIS-based landslide hazard analysis by SINMAP(Stability Index MAPping) model in Gyeonggi Icheon area coupling with geomorphological and geological data. SINMAP model has its theoretical basis in the infinite plane slope stability model with wetness obtained from a topographically based steady state model of hydrology. To Gyeonggi Icheon area landslides hazards evaluated, these SINMAP model were analysed results while simultaneously referring to the stability index map, where lines distinguish the zones categorized into the different stability classes and a table giving summary statistics.