• Title/Summary/Keyword: f-stable

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Molecular Cloning and Expression of a Novel Protease-resistant GH-36 $\alpha$-Galactosidase from Rhizopus sp. F78 ACCC 30795

  • Yanan, Cao;Wang, Yaru;Luo, Huiying;Shi, Pengjun;Meng, Kun;Zhou, Zhigang;Zhang, Zhifang;Yao, Bin
    • Journal of Microbiology and Biotechnology
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    • v.19 no.11
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    • pp.1295-1300
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    • 2009
  • A 2,172-bp full-length gene (aga-F78), encoding a protease-resistant $\alpha$-galactosidase, was cloned from Rhizopus sp. F78 and expressed in Escherichia coli. The deduced amino acid sequence shared highest identity (45.0%) with an $\alpha$-galactosidase of glycoside hydrolase family 36 from Absidia corymbifera. After one-step purification with a Ni-NTA chelating column, the recombinant Aga-F78 migrated as a single band of ~82 and ~210 kDa on SDS-PAGE and nondenaturing gradient PAGE, respectively, indicating that the native structure of the recombinant Aga-F78 was a trimer. Exhibiting the similar properties as the authentic protein, purified recombinant Aga-F78 was optimally active at $50^{\circ}C$ and pH 4.8, highly pH stable over the pH range 5.0-10.0, more resistant to some cations and proteases, and had wide substrate specificity (pNPG, melidiose, raffinose, and stachyose). The recombinant enzyme also showed good hydrolytic ability to soybean meal, releasing galactose of $415.58\;{\mu}g/g$ soybean meal. When combined with trypsin, the enzyme retained over 90% degradability to soybean meal. These favorable properties make Aga-F78 a potential candidate for applications in the food and feed industries.

Study on Roughage Degradation and Adhesion of Rumen Fibrolytic Bacteria by Real-Time PCR (Real-Time PCR 기법을 이용한 반추위 섬유소분해 박테리아의 부착과 조사료 분해에 관한 연구)

  • Sung, Ha Guyn
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.34 no.1
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    • pp.60-67
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    • 2014
  • The comparisons between cellulolytic bacteria adhesion on rice straw and fiber digestion in time course during rumen fermentation were studied in situ. The adhesions of cellulolytic bacteria, F. succinogenes. R. albus and R. flavefaciens, were measured by RT-PCR. When the rice straws were incubated at 0. 2, 4, 8, 12 and 24 hours of the in situ rumen, straw was degraded with increasing speed during the incubation and showed the highest disappearance increasing rate (DM g/h) from 8 to 12 hour. The adhesions of F. succinogenes, R. flavefaciens and R. albus were achieved above 80% in 1 hour of in situ rumen fermentation and then keep adhesive population up after the time of fermentation. When the in situ samples were collected at 0, 5, 10, 30 and 60 min to detect the early stages of adhesion on the rice straws ingested into rumen, the numberous adhesive colony of F. succinogenes, R. flavefaciens and R. albus were detected in 5 min. In case of rice straw treated with 0, 2, 4 and 8% NaOH, all of three cellulolytic bacteria showed the increasing trends of adhesion with increasing DM disappearance of rice straw by higher concentration of NaOH at 12 hour of in situ. However, there were showed respectively difference at 24 hour. The present results gave certain evidence that adhesion of cellulolytic bacteria is definitely achieved in early stage of roughage ingestion into rumen, their colony develop the stable communities on roughage in process of rumen fermentation and then fiber degradation is accelerated.

Study on the Effect of Bloodletting on Back-Shu Points and Sabonghyeul with Ryodoraku (양도락을 이용한 사봉혈과 배수혈의 사혈요법 효과 연구)

  • Koo, Jin Suk
    • Journal of Convergence for Information Technology
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    • v.11 no.9
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    • pp.173-181
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    • 2021
  • The purpose of this study is to prove the existence of the meridians by analyzing the effect of bloodletting cupping on Back-Shu Points and venesection on sabonghyeul, which are treatments for gastrointestinal and circulatory diseases with Ryodoraku. We selected the charts of 30 patients who received the treatment such as bloodletting cupping on Back-Shu Points and venesection on sabonghyeul for gastrointestinal and circulatory diseases. First, the Ryodoraku test was conducted in a stable state. After taking a rest on the bed, he performed a venesection on sabonghyeul. And bloodletting cupping on Back-Shu Points was performed with prone position. After all the procedures were completed, Ryodoraku test was performed again. And the result was compared with previous test status. By bloodletting cupping on Back-Shu Points and venesection on sabonghyeul, the deviation between the current value of the right F5 (gallbladder)· H4 (small intestine)· H6 (large intestine) (p<.05, p<.05, p<.001), left H5 (triple energizer) (p<.05) and the average current of 24 source points was significantly decreased. The difference between the left and right currents at the site of F3 (kidney) showed a significant increase (p<.005). It can be proved the existence of meridians that Bloodletting cupping on Back-Shu Points and venesection on sabonghyeul showed significant changes in the F5 (gallbladder), H4 (small intestine), H6 (large intestine), F3 (kidney), H5 (triple energizer) in digestive and circulatory symptoms by Ryodoraku test.

New Thermostable Chitosanase from Bacillus sp.: Purification and Characterization

  • Yoon, Ho-Geun;Ha, Sang-Chul;Lim, Young-Hee;Cho, Hong-Yon
    • Journal of Microbiology and Biotechnology
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    • v.8 no.5
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    • pp.449-454
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    • 1998
  • A thennostable chitosanase was purified from Bacillus sp. KFB-C108, by fractionation of 30 to 70% saturation with ammonium sulfate, DEAE-Toyopearl chromatography, Butyl-Toyopearl chromatography, and TSK-Gel HW-55F gel filtration. The purified enzyme showed a single band on sodium dodecyl sulfate polyacrylamide gel electrophoresis, and the molecular weight was estimated to be 48 kDa. The enzyme degraded soluble chitosan and colloidal chitosan, but did not degrade glycol chitosan, chitin, and the other compounds investigated. There was no effect on the chitosanase activity by treatment with chelating agents, alkylating agents, and various metals investigated, and only cobalt ions inhibited the activity. Optimum temperature and pH were $55^{\circ}C$ and 6.5, respectively. The enzyme was stable after heat treatment at $80^{\circ}C$ for 10 min or $70^{\circ}C$ for 30 min and fairly stable in several organic solvents as well. Chitosan was hydrolyzed to $(GlcN)_4$as a major product by incubation with the enzyme.

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Buffering effects of shock loads in sequencing batch reactor (SBR에서 충격부하에 따른 완충효과)

  • Ji, Dae-Hyun;Lee, Kwang-Ho;Lee, Jae-Kune
    • Journal of Korean Society of Water and Wastewater
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    • v.22 no.5
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    • pp.581-587
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    • 2008
  • In this study, we investigated the buffering effect with different COD, $NH_4{^+}-N$ and TP shock loads on the performance of lab-scale Sequencing Batch Reactor(SBR) using synthetic wastewater. This study was operated under the following conditions : HRT, 12 hrs : MLSS, 2,000 mg/L : F/M ratio, $0.2kgCOD/kgMLSS{\cdot}d$ : SRT, 20days, and was increased by a factor, COD : ranging from 200-2000 mg/L, $NH_4{^+}-N$ : ranging from 30-300 mg/L, T-P : ranging from 5-50 mg/L in the reactor. As results, COD removal rate at different shock loads was decreased until 42.1%(stable state : 95%) and concentration with effluent was higher than 695 mg/L(at Run 6). In case of $NH_4{^+}-N$ removal rate was decreased until 35.8% from 97.0% and also T-P removal rate was decreased until 5.0%. Effluent concentrations of COD, $NH_4{^+}-N$ and T-P were rapidly increased according to shock loads and needed 3, 4 and 6 additional cycle times for recovering the stable condition.

Stabilization of Thermo Electromotive Force of Power Type Shunt Resistor for Mass Storage Secondary Battery Management System (대용량 이차전지 관리 시스템용 전력형 션트저항의 열기전력 안정화)

  • Kim, Eun Min;Lee, Sunwoo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.30 no.6
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    • pp.376-380
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    • 2017
  • In this paper, we prepared a metal alloy resistor with stable thermal electro motive force (thermal EMF) as well as a low temperature coefficient of resistance (TCR) by adjusting the manganese proportion from 3 to 12 wt% in the Cu-Mn-Ni alloy. Composition of the fabricated metal alloy was investigated using energy dispersive X-ray (EDX) analysis. The TCR of each sample was measured as 44.56, 40.54, 35.60, and 31.56 ppm for Cu-3Mn-2Ni, Cu-5Mn-2Ni, Cu-10Mn-2Ni, and Cu-12Mn-2Ni, respectively. All the resistor samples were available for the F grade (${\pm}1%$ of the allowable error of resistance) high-precision resistor. All the samples satisfied the baseline of high thermal EMF (under 3 mV at $60^{\circ}C$); however, Cu-3Mn-2Ni and Cu-5Mn-2Ni satisfied the baseline of low thermal EMF (under 0.3 mV at $25^{\circ}C$). We were thus able to design and fabricate the metal alloy resistor of Cu-3Mn-2Ni and Cu-5Mn-2Ni to have low TCR and stable thermal EMF at the same time.

The Null Distribution of the Likelihood Ratio Test for a Mixture of Two Gammas

  • Min, Dae-Hee
    • Journal of the Korean Data and Information Science Society
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    • v.9 no.2
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    • pp.289-298
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    • 1998
  • We investigate the distribution of likelihood ratio test(LRT) of null hypothesis a sample is from single gamma with unknown shape and scale against the alternative hypothesis a sample is from a mixture of two gammas, each with unknown scale and unknown (but equal) scale. To obtain stable maximum likelihood estimates(MLE) of a mixture of two gamma distributions, the EM(Dempster, Laird, and Robin(1977))and Modified Newton(Jensen and Johansen(1991)) algorithms were implemented. Based on EM, we made a simple structure likelihood equation for each parameter and could obtain stable solution by Modified Newton Algorithms. Simulation study was conducted to investigate the distribution of LRT for sample size n = 25, 50, 75, 100, 50, 200, 300, 400, 500 with 2500 replications. To determine the small sample distribution of LRT, I considered the model of a gamma distribution with shape parameter equal to 1 + f(n) and scale parameter equal to 2. The simulation results indicate that the null distribution is essentially invariant to the value of the shape parameter. Modeling of the null distribution indicates that it is well approximated by a gamma distribution with shape parameter equal to the quantity $0.927+1.18/\sqrt{n}$ and scale parameter equal to 2.16.

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The Effect of Intake Swirl Ratios on Combustion Performance in a Heavy-Duty LPG Engine (대형 LPG 엔진의 흡입 스월비에 따른 연소성능에 관한 연구)

  • 한병주;김창업;강건용;이창식
    • Transactions of the Korean Society of Automotive Engineers
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    • v.9 no.5
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    • pp.46-53
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    • 2001
  • To optimize the intake flow condition in the heavy-duty LPG SI engine, five different swirl ratios of intake port were investigated experimentally by oil spot method, LDV and single cylinder engine test. The flow characteristics near the piston surface were observed by oil spot method and magnitudes of swirl flow were measured quantatively by LDV method in the steady flow rig. The engine performances of various swirl flow were also tested with the heavy-duty LPG SI single cylinder engine. In the results, high swirl ratio, above $R_s$=2.3, was not suitable to develope a stable flame kernel and to produce high engine performance. Especially it was more serious under lean burn conditions, since turbulence intensity was smaller than bulk flow though those are increased together. These results were also confirmed by LDV measurement and oil spot method. On the contrary, low swirl ratio($R_s$=1.3) is not good to propagate a flame since the turbulence intensity and bulk flow are vanished during compression stroke and low swirl ratio has too weak initial energy for stable combustion. Therefore, the of optimized swirl ratio f3r the heavy-duty LPG engine in this work was found around $R_s$=2.0.

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Estimation of Lateral Dispersion Parameter using Observed Wind Direction Fluctuation in Chunchon (풍향변동량 측정에 의한 춘천지역의 연기 수평확산폭 산출)

  • 이종범;김정식;김용국;조창래
    • Journal of Korean Society for Atmospheric Environment
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    • v.12 no.2
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    • pp.141-149
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    • 1996
  • Lateral dispersion parameter(.sigma.$_{y}$) which is an important factor in atmospheric dispersion can be estimated byusing wind direction fluctuation(.sigma.$_{\theta}$). In this paper, we studied the characteristics of the .sigma.$_{\theta}$ in the Chunchon basin and calculated the .sig- ma.$_{y}$ by using the .sigma.$_{\theta}$. We could find some characteristics of the .sigma.$_{\theta}$ which showed small value, when the atmospheric condition was in weak unstable (C class) and neutral (D class). Moreover, when the atmospheric stability was neutral, there was no difference of .sigma.$_{\theta}$ with wind speed. On the other hand, .sigma.$_{\theta}$ showed large values at the strong unstable (A class) and strong stable (F class) condition with low wind speed. In this case, the .sigma.$_{\theta}$ increased as long as averaging time due to the long-period wind direction fluctuation by the terrain effect. In the result of calculation of .sigma.$_{y}$, it was smaller than that of pasquill-Gifford curve. Especially, when the atmospheric condition was in a neutral and stable, .sigma.$_{y}$ showed small increment as the downwind distance increased.creased.

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Active shape change of an SMA hybrid composite plate

  • Daghia, Federica;Inman, Daniel J.;Ubertini, Francesco;Viola, Erasmo
    • Smart Structures and Systems
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    • v.6 no.2
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    • pp.91-100
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    • 2010
  • An experimental study was carried out to investigate the shape control of plates via embedded shape memory alloy (SMA) wires. An extensive body of literature proposes the use of SMA wires to actively modify the shape or stiffness of a structure; in most cases, however, the study focuses on modeling and little experimental data is available. In this work, a simple proof of concept specimen was built by attaching four prestrained SMA wires to one side of a carbon fiber laminate plate strip. The specimen was clamped at one end and tested in an environmental chamber, measuring the tip displacement and the SMA temperature. At heating, actuation of the SMA wires bends the plate; at cooling deformation is partially recovered. The specimen was actuated a few times between two fixed temperatures $T_c$ and $T_h$, whereas in the last actuation a temperature $T_f$ > $T_h$ was reached. Contrary to most model predictions, in the first actuation the transformation temperatures are significantly higher than in the following cycles, which are stable. Moreover, if the temperature $T_h$ is exceeded, two separate actuations occur during heating: the first follows the path of the stable cycles; the second, starting at $T_h$, is similar to the first cycle. An interpretation of the phenomenon is given using some differential scanning calorimeter (DSC) measurements. The observed behavior emphasizes the need to build a more comprehensive constitutive model able to include these effects.