• Title/Summary/Keyword: ${\beta}$ Value

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Comparison of Monoterpene Emission Rates from Conifers (침엽수로부터 발생되는 방향성 테르펜의 배출속도 비교 연구)

  • Kim Jo-Chun;Hong Ji-hyung;Gang Change-Hee;Sunwoo Young;Kim Ki-Joon;Lim Jun-Ho
    • Journal of Korean Society for Atmospheric Environment
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    • v.20 no.2
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    • pp.175-183
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    • 2004
  • In order to investigate the composition ratio and the emission rate of monoterpenes emitted from coniferous trees during summer, the enclosure chamber experiments were carried out for two tree species (Pinus densiflora and Pinus rigida). The major monoterpenes from the pine trees were $\alpha$-pinene, $\beta$-pinene, myrcene and $\beta$-phellandrene. There was no difference of the composition ratio between two sites for P. densiflora, but the difference was observed for P. rigida. Clearly, the ratio of $\beta$-pinene (26.1 %) for P. rigida was higher than that of $\beta$-phellandrene (12%) at the Gumsung mountain site, but the ratio of $\beta$-phellandrene (22.2%) was higher than that of $\beta$-pinene (9.9%) at the Chiri mountain site. Particularly, the composition ratio of $\beta$-phellandrene was higher than that of $\beta$-pinene for P. densiflora, and the opposite trend was found for P. rigida at the Gumsung mountain site. The characteristics of the composition ratio between two species were similar at the Chiri mountain site. As a result of the emission rate measurements, it was observed that both sites did not show any significant $\beta$ value (slope between emission rate and temperature) and ERs (Standard Emission rate at 3$0^{\circ}C$) difference. However, the $\beta$ value and ERs at the Chiri mountain site were slightly greater than those of Gumsung mountain site for both pine species. P. densiflora (1.703 and 1.971 $\mu\textrm{g}$C/gdw/hr) showed the higher monoterpene ERs than those of P. rigida (0.572 and 0.698 $\mu\textrm{g}$C/gdw/hr) at both sites.

$\beta$-Alanine Induced Down-Regulation of the Taurine Transporter Activity in the Human Colon Carcinoma Cell Line (HT-29) (인체 소장상피세포주 모델(HT-29)에서 $\beta$-알라닌이 타우린수송체 활성에 미치는 영향)

  • 박태선;윤미영;정한나;이해미
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.2
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    • pp.314-319
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    • 2001
  • In the present study, effects of $\beta$-alanine, a known taurine antagonist for its structural similarity, on the adaptive regulation and kinetic behavior of the taurine transporter were investigated in the HT-29, human colon carcinoma cell line. Pretreatment of the cell with $\beta$-alanine(10mM) for varying periods from 3 to 30 hrs significantly reduced the taurine uptake compared to the value for control cells. This decrease in the taurine transporter activity was dependent on the incubation time with $\beta$-alanine, and the maximal down-regulation of the transporter activity was observed in cells pretreated with $\beta$-alanine for 24 hrs (25% of the control value, p<0.01). The taurine transporter appears to bind exclusively with $\beta$-alanine in the HT-29 cells since the same concentration of $\alpha$-alanine added in the culture medium for 24 hrs did not influence the taurine uptake. Kinetic analyses of the taurine transporter activity was performed in the HT-29 cell line with varying taurine concentration (5~60$\mu$M) in the uptake medium. Active taurine uptake was significantly lower in $\beta$-alanine pretreated cells compared to the value for control cells in the range of taurine concentration used in the experiment (p<0.001). The cells pretreated with $\beta$-alanine showed a 50% lower maximal velocity (Vmax, 1.7$\pm$2.0 nmole.mg $protein^{-1}$.$30min^{-1}$), and a 99% higher Michaelis constant (Km, 40.3$\pm$7.6$\mu$M) than the control values (3.3$\pm$1.9 nmole.mg $protein^{-1}$.$30min^{-1}$, and 20.3$\pm$2.1$\mu$M, respectively). These results on kinetic data suggest that $\beta$-alanine induced down-regulation of the taurine transporter activity was associated with decreases in both maximal velocity and affinity of the transporter.

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Purification and Characteristics of ${\beta}$-Galactosidase from Strawberry (딸기 ${\beta}$-Galactosidase의 정제 및 생화학적 특성)

  • Lee, Kwang-Hee;Yoon, Kyung-Young;Kim, Kwang-Soo;Kim, Nam-Woo;Shin, Seung-Ryeul
    • Food Science and Preservation
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    • v.7 no.2
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    • pp.201-206
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    • 2000
  • ${\beta}$-Galactosidase was extracted and purified from strawberry. The purified ${\beta}$-Galactosidase from strawberry was investigated their physicochemical characteristics. ${\beta}$-Galactosidase was purified 25.74 fold from strawberry. The purification procedure include ammonium sulfate fraction, acetone powder treatment and gel and ion exchange chromatography. Yield of the enzyme purification was 18.11%. The purified enzyme has native molecular weight of 116,000 dalton. Vmax value and Km value of ${\beta}$-Galactosidase were 0.077 mM ONPG/ml/15mim and 1.75x10-2mM, respectively. The optimum temperature and pH of ${\beta}$-Galactosidase were 43$^{\circ}$C and pH 4.0, respectively. The ${\beta}$-Galactosidase activity was stable below 50$^{\circ}$C and at pH 4.0 to pH 6.0. Among the metal ions Ca and Mg were did not affect, whereas K, Cu and Zn show a little effect on the enzyme activity. The ${\beta}$-Galactosidase activities were inhibited by treatment with EDTA and SDS.

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Bayesian Inferences for Software Reliability Models Based on Beta-Mixture Mean Value Functions

  • Nam, Seung-Min;Kim, Ki-Woong;Cho, Sin-Sup;Yeo, In-Kwon
    • The Korean Journal of Applied Statistics
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    • v.21 no.5
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    • pp.835-843
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    • 2008
  • In this paper, we investigate a Bayesian inference for software reliability models based on mean value functions which take the form of the mixture of beta distribution functions. The posterior simulation via the Markov chain Monte Carlo approach is used to produce estimates of posterior properties. Its applicability is illustrated with two real data sets. We compute the predictive distribution and the marginal likelihood of various models to compare the performance of them. The model comparison results show that the model based on the beta-mixture performs better than other models.

Effects of Job Characteristics on Job Burnout and Engagement in School Foodservice Dietitians in Busan Area (부산지역 학교영양(교)사의 직무변인이 직무소진과 직무열의에 미치는 영향)

  • Lyu, Eun-Soon;Lee, Kyung-A
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.1
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    • pp.132-139
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    • 2017
  • The purpose of this study was to obtain data for contribution of job characteristics (workload, autonomy, reward, community, fairness, and value) to job burnout (emotional exhaustion, and cynicism), and job engagement (vigor, dedication, and absorption) in foodservice dietitians. Our survey was administered to 393 school foodservice dietitians in the Busan area on February 11, 2014. The mean scores of nutrition teachers were significantly higher for autonomy (P<0.01), reward (P<0.05), community (P<0.01), fairness (P<0.001), and value (P<0.001) than unlimited period contract dietitians. The mean scores of high school dietitians were significantly higher for emotional exhaustion (P<0.01) and cynicism (P<0.001) than elementary school dietitians and middle school dietitians. Workload (r=-0.609, P<0.001), reward (r=-0.417, P<0.001), and fairness (r=-0.394, P<0.01) correlated significantly with emotional exhaustion. Reward (r=-0.324) and value (r=-0.423) correlated significantly (P<0.01) with cynicism. Value correlated significantly (P<0.01) with vigor (r=0.493), dedication (r=0.480), and absorption (r=0.460). Workload (${\beta}=-0.521$, P<0.001) had the highest negative influence on emotional exhaustion, whereas value (${\beta}=-0.325$, P<0.001) had the highest negative influence on cynicism. Value had the highest positive influence on vigor (${\beta}=0.392$, P<0.001), dedication (${\beta}=0.443$, P<0.001), and absorption (${\beta}=0.444$, P<0.001). Based on the results of this study, school management should plan job characteristics strategies to reduce workload and increase value for school foodservice dietitians.

Kinetics and Mechanism of Pyridinolysis of Aryl Dithiocyclopentanecarboxylates in Acetonitrile

  • Oh, Hyuck-Keun
    • Bulletin of the Korean Chemical Society
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    • v.31 no.8
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    • pp.2357-2360
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    • 2010
  • Kinetic studies on the pyridinolysis of aryl dithiocyclopentanecarboxyaltes 2 were carried out at $60.0^{\circ}C$ in acetonitrile. In the aminolysis of 2, the $\beta_X$ values were 0.5 - 0.8 with anilines, and there was no breakpoint. However, in the pyridinolysis of 2, biphasic Bronsted plots were obtained, with a change in slope from a large value ($\beta_X{\cong}0.7$) to a small value ($\beta_X{\cong}0.4$) at $pK_{a}^0$ = 5.2. This was attributed to a change in the rate-limiting step from breakdown to the formation of a zwitterionic tetrahedral intermediate, $T^{\pm}$, in the reaction path, with an increase in the basicity of the pyridine nucleophile. An obvious change in the cross-interaction constant ${\rho}_{XZ}$ from a large positive ($\rho_{XZ}$ = +1.02) value to a small negative value (${\rho}_{XZ}$ = -0.17) supports the proposed mechanistic change.

The Prediction of Mastery-Approach Goal Orientation, Task Value, and Self-Regulated Learning Strategy on Academic Satisfaction and Achievement of Cyber Engineering University Students (사이버대학교 공학계열 학생들의 숙달접근목표지향성, 과제가치, 자기조절학습전략의 학업만족도와 학업성취도 예측력 규명)

  • Joo, Young-Ju;Chung, Ae-Kyung;Seol, Hyun-Nam;Yi, Sang-Hoi
    • 전자공학회논문지 IE
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    • v.49 no.2
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    • pp.65-74
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    • 2012
  • The purpose of this study is to verify the prediction of mastery-approach goal orientation, task value, and self-regulated learning strategy on academic satisfaction and achievement of cyber engineering university students. For this study, 219 engineering students of H cyber university who enrolled in the spring semester of 2011 was chosen and completed web surveys. A hypothetical model proposed included mastery-approach goal orientation, task value, and self-regulated learning strategy as predictors, and academic satisfaction and achievement as criteria variables. The results of this study through multiple regression analysis indicated that task value(${\beta}$=.401) and self-regulated learning strategy(${\beta}$=.401) predicted significantly on academic satisfaction. In addition, self-regulated learning strategy(${\beta}$=.301) and mastery-approach goal orientation(${\beta}$=.196) predicted significantly on academic achievement. The result of this study suggested that mastery-approach goal orientation, task value, and self-regulated learning strategy should be considered for improving academic satisfaction and achievement in cyber engineering education.

Performance Comparison of Exponential Effective SINR Mapping with Traditional Actual Value Interface for Different Transmission Schemes in OFDM Systems (OFDM 시스템에서 전송방법에 있어 Exponential Effective SINR Mapping 방법과 기존방법과의 성능비교)

  • Iqbal, Asif;Cho, Sung-Ho;Park, Jung-Min
    • Proceedings of the KIEE Conference
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    • 2008.04a
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    • pp.163-165
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    • 2008
  • In this paper we compare performance of exponential effective SINR mapping (EESM) with traditional actual value interface (AVI) approach for various modulation and coding schemes (MCS) in terms of coded bit error rate (BER) or block error rate (BLER) using different transmission schemes. This paper provides explanation and comparison of the two algorithms for single input single output (SISO), and single input multi-output (SIMO, 1X2) in OFDM systems. We calibrate the value of beta ($\beta$) in EESM using large number of channel realizations, here $\beta$ is a calibration constant. This paper also presents importance of beta value in EESM and how it improves the performance of OFDM wireless systems. We propose different modulation and coding schemes. Here we consider Standford university interim (SUI) channel models. Furthermore this paper also shows the detail observation of the two algorithms. Finally the conclusion review given for short summary.

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Protection of Minority Shareholder Investment in the Small and Medium-sized Enterprises

  • KANTHAPANIT, Chinnapat;KANTHAPANIT, Chutiya
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.8
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    • pp.451-459
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    • 2020
  • This study aims to examine the relationship of the four factors that increase the protection of minority shareholder investment. The factors are non-controlling shareholders, corporate governance, free cash flow, and shareholder wealth. The data for this study is obtained from the 2017 annual reports of 136 Thai public companies listed in the Market of Alternative Investment of Thailand (MAI). The analysis uses a multiple regression model to determine which factors encourage and which inhibit the protection of minority shareholder investment. The study tests four hypotheses. The results rejected H1 because non-controlling shareholders have negatively correlated with minority shareholder investment protection (beta -0.155 and p-value 0.050). The results accepted H2, H3 and H4 as follows. H2: corporate governance has positively correlated with minority shareholder investment protection (beta 0.17 and p-value 0.031). H3: free cash flow has positively correlated with minority shareholder investment protection (beta 0.214 and p-value 0.007). H4: shareholder wealth has positively correlated with minority shareholder investment protection (beta 0.318 and p-value 0.000). The major findings suggest strong minority shareholder investment protection was enhanced by increasing corporate governance, free cash flow and shareholder wealth. The protection of minority shareholder investment needs to reduce non-controlling shareholding pattern.

라드를 이용한 열처리 온도 변화에 따른 ${\beta}-carotene$의 산화 안정성에 대한 연구

  • Won, Hye-Gyeong;Jeong, Sang-Hui;Hwang, Mi-Ja;Kim, Jin-Hui;Lee, Ji-Yeong;Park, Nam-Yeong;Lee, Chi-Ho
    • Proceedings of the Korean Society for Food Science of Animal Resources Conference
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    • 2005.05a
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    • pp.358-362
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    • 2005
  • 0%, 0.0012%, 0.004%의 ${\beta}-carotene$을 lard를 첨가한후 $80^{\circ}C$, $130^{\circ}C$, $180^{\circ}C$의 온도처리로 2분간 열처리를 하고 $50^{\circ}C$에서 보관시키면서 각 기간별로 총 균수검사, 과산화물가(Peroxide Value), TBArs를 측정하여 비교하였다. 1) 미생물 총 균수 실험에서 ${\beta}-carotene$의 첨가량이 0%, 0.0012%, 0.004%로 증가함에 따라 균의 증식이 둔화되었다. 2) Peroxide Value의 측정 실험에 ${\beta}-carotene$의 첨가량이 0.004%일 때가 0%, 0.0012%에서 보다 항산화 능력이 더 높은 것으로 나타났다. 3) TBA가 측정실험에서 control과 Sample과의 비교에서 온도가 증가함에 따라 그 증가폭 커지므로 ${\beta}-carotene$의 항산화 능력이 있다는 것을 알 수 있다.

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