• Title/Summary/Keyword: Activity Coefficient

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fMRI of Visual and Motor Stimuli : Difference of Total Activation Depends on Stimulation Paradigm (시각과 운동의 뇌기능영상 : 자극에 따른 총활성화의 차이)

  • 정순철;송인찬;장기현;유병기;문치웅;조장희
    • Investigative Magnetic Resonance Imaging
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    • v.3 no.1
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    • pp.41-46
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    • 1999
  • Purpose : To investigate the difference of total activation in visual area, motor area, and cerebellum according to the stimulation paradigm. Materials and Methods : Functional MR imaging was performed in 5 healthy volunteers with visual and motor activity using EPI technique. LED and Checker-Board stimulation were performed for visual activity. Thumb motion and Finger Tapping were performed for motor and cerebellum activity. Stimulus timing was 60sec. off, 120sec. on, 60sec. off. Data processing was carried out by using the cross-correlation method for each pixel. Each pixel was then selected and assumed activated if the correlation coefficient was equal or larger than a threshold value. Time course data was obtained by calculating the total activation which was defined as the number of activated pixel x averaged pixel intensity. Results : In the case of visual activity with LED stimulation, we found increased total activity of more than 100% compared with Checker-Board stimulation. In the case of motor area and cerebellum with Finger tapping stimulation, we found increased total activity of more than 10% and 150%, respectively compared with Thumb motion stimulation.

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The Effect of Gender on the Gastric Alcohol Dehydrogenase (GADH) Activity in Normal Sprague-Dawley Rats (Sprague-Dawley계 정상 흰쥐에서 위점막 알코올 탈수소효소 활성에 대한 성별의 영향)

  • 성기철;강주섭;이창호;고현철;신인철;강석한;전용철;엄애선
    • Biomolecules & Therapeutics
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    • v.8 no.1
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    • pp.38-43
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    • 2000
  • Several studies have shown that the stomach has sufficient alcohol dehydrogenase (ADH) activity to metabolize some amount of orally administered alcohol and the sex-related differences in the first-pass metabolism of alcohol might be associated with differences in the activity of gastric ADH(GADH). The aim of this study was to asses the sex-related differences in GADH in 48 male and 48 female Sprague-Dawley rats aged 1, 4, 10, 15, 20, and 30 weeks which each aged group had same sex ratio. The GADH activity was determined spectrophotometrically at 37$^{\circ}C$. The formation of NADH was monitored at 340nm for 10 minutes in the 1 ml of reaction mixture (0.5 M of Tris-HCl, pH 7.2 + 1.5 M of ethanol + 2.8 mM of NAD + 30 $\mu$l gastric mucosal supernatant). The GADH activity (nM of NADH/min/mg of cytosolic protein) was calculated using molecular extinction coefficient of 6.22 $\textrm{cm}^2$/$\mu$M for NADH. The GADH activities were 2.94$\pm$0.82 (n=48) in female rats and 3.34$\pm$2.17 (n=48) in male rats and had not significant difference between sex. However, the GADH activities were significantly (p<0.01) higher in female (1.91$\pm$0.59 and 3.30$\pm$0.49) than in male (0.68$\pm$0.43 and 1.92$\pm$0.81) of 1 and 4 weeks rats. However, it was significantly (p<0.05) higher in male (6.48$\pm$1.81, 3.65$\pm$1.04 and 5.13$\pm$1.30) than in female (4.23$\pm$1.23, 2.18$\pm$0.77 and 2.56$\pm$0.93) of 10, 20 and 30 weeks rats, respectively. Therefore, the results suggested that sex-related differences of the GADH activities in same aged rats were existed by age.

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Modeling and Measurements of the Activity Coefficients and Solubilities of Amino Acids in the L-valine/electrolyte and L-proline/electrolyte Aqueous Solutions (L-Valine/전해질 및 L-Proline/전해질 수용액에서 아미노산의 활동도계수와 용해도의 측정 및 모델링)

  • Lee, Bong-Seop;Kim, Ki-Chang
    • Korean Chemical Engineering Research
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    • v.50 no.1
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    • pp.93-105
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    • 2012
  • Activity coefficients and solubilities of L-Valine and L-Proline in aqueous solutions containing each of four electrolytes such as NaCl, KCl, $NaNO_3$ and $KNO_3$ were measured at 298.15 K. The measurements of activity coefficients were carried out in the electrochemical cell coupled with two ion-selective electrodes (cation and anion), and the solubilities were measured by the gravimetric analysis of saturated solutions in equilibrium with the solid phase of amino acid. The measured activity coefficients of electrolytes and amino acids were correlated with the theoretical thermodynamic model presented in the previous work [Korean Chem. Eng. Res. 48(4), 519(2010)]. It was found that the activity coefficients of amino acids and electrolytes described based on the our previous model were well agreeable with experimental data. Also the experimental solubility data of L-Valine and L-Proline were successfully correlated with the thermodynamic relation mentioned in the previous work.

Topical Formulation and Antimicrobial Activity of Ketonic Fraction from Leptospermum scoparium (Leptospermum scoparium의 케톤체 분획물을 함유한 외용제제의 항균력)

  • Kim, Eun-Hee;Hwang, Sung-Joo;Park, Song-Hee;Park, Seung-Youg;Rhee, Gye-Ju
    • Journal of Pharmaceutical Investigation
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    • v.30 no.3
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    • pp.151-158
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    • 2000
  • Gel and cream containing 5% and 10% ketonic fraction (KF) of Leptospermum scoparium, respectively were formulated. Antimicrobial activity, stability, anti-inflammatory effect, rheological properties, drug release and acute toxicity for these topical efficacy were evaluated. Gel and cream containing neomycin or gentamycin in combination with KF has potent antimicrobial activity. Gel and cream were physically stable and did not show any creaming for 6 months storage. Gel showed plastic flow with yield value and cream showed pseudoplastic flow with hysteresis loop. The gel and cream containing KF showed higher viscosity than control or commercial one. The viscosity increased as the concentration of KF increased. Both 10% gel and cream showed a significant decrease in swelling when applied to the carrageenan- injected paw, suggesting local antiinflammatory activity. Particularly, 10% gel preparation showed similar antiinflammatory activity when compared with commercially available drugs. Percent of drug released and diffusion coefficient were in the order of 5% gel, 10% gel, 5% cream, and 10% cream, respectively. There were no significant changes of body weight in rats percutaneously administered with 10% cream and gel when compared with control. There were no induced acute toxicity when 10% cream or gel was applied to rats. Leptospermum scoparium could be practicaly used in topical preparations.

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Assessment of Physical Activity Level of Korean Farmers to Establish Estimated Energy Requirements during Busy Farming Season (농번기 농업인의 에너지필요추정량 설정을 위한 활동량 및 신체활동수준 평가)

  • Kim, Eun-Kyung;Lee, Sun-Hee;Ko, Su-Young;Yeon, Seo-Eun;Choe, Jeong-Sook
    • Korean Journal of Community Nutrition
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    • v.16 no.6
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    • pp.751-761
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    • 2011
  • The purpose of this study was to assess the physical activity level of Korean farmers to establish their estimated energy requirements during busy farming season. 113 farmers (mean age $51.9{\pm}7.2$ years, male 42, female 71) who own farmland area above 300 pyung participated in measurement of body weight and height and interviewing of one-day activity diaries. There was no significant difference in age, BMI between male and female. Obesity prevalence according to BMI among male and female farmers was 40.5% and 50.7% respectively. The farmers spent about 7 hours in sleeping and spent about 4 hours 35 minutes working on the farm and spent about 15 hours 30 minutes (64.6% of 24 hours) in "very light activities" and spent about 3 hours 31 minutes (14.7%) in "light activities". Physical activity level (PAL, activity coefficient) of male farmers was 2.63 which was significantly higher than that (2.19) of female farmers (p < 0.05). Estimated energy requirements (EER) for farmers who were different in age and gender were suggested. For example, the estimated energy requirements for male and female farmers were 3058 kcal/day and 2279 kcal/day, respectively. The results of this study suggest that estimated energy requirements (EER) of farmers should be differentiated according to seasonal workload and energy balance of farmers should be evaluated to prevent obesity.

Comparison of Riboflavin Status between Traditional Farming Women and Commercial Farming Women in Korea

  • Lim, Hwa-Jae;Yoon, Jin-Sook
    • Korean Journal of Community Nutrition
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    • v.2 no.5
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    • pp.701-710
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    • 1997
  • this study was undertaken to compare the riboflavin status of rural women with different physical activity intensity and to determine factors influencing biochemical fiboflavin status. The study was carried out over three different farming seasons : planting (June), harvest(October) and interim(February) in two rural regions of Korea. One was a traditional farming region, the other a commercial farming region with heavier work intensity. Twenty women in the traditional region and eighteen women in the commercial region were involved. The intensity of physical activity was determined by a daily activity record. Body composition was assessed by bioelectrical impedence. Dietary riboflavin intake was measured by the food frequency method. Riboflavin biochemical status was assessed by erythrocyte glutathione reductase activity coefficient (EGR AC) and ruinary riboflavin excretion. The results from the EGR AC and urinary riboflavin excretion during the period showed the overall riboflavin status of the commercial farming women was significantly worse than that of the traditional farming women(EGR AC p<0.0001, urinary riboflavin excretion p<0.05). The traditional farming group had about 40% with risk of riboflavin deficiency, whereas the commercial farming group had about 70%. Overall mean nutrient intake was not significantly different between the two groups, however, overall mean percent lean body mass representing long term physical activity was significantly higher in the commercial farming group ( <0.005). It appears that the biochemical riboflavin status of traditional farming women was significantly influenced by riboflavin intake and crude nitrogen balance while the biochemical riboflavin status of the commercial farming women was significantly influenced by riboflavin intake and percent of lean body mass over the three seasons. (Korean J Community Nutrition 2(5) : 701∼710, 1997)

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Impediment in Activity of Daily Living and Social Support for Rural Elderly Farmers Undergoing Nerve Block due to Low Back Pain (만성요통으로 신경차단술을 받은 농촌 노인들의 사회적 지지와 일상생활 활동장애에 관한 연구)

  • Choi, In Young;Hwang, Moon Sook
    • Research in Community and Public Health Nursing
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    • v.30 no.2
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    • pp.206-216
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    • 2019
  • Purpose: This study is to investigate the low back pain, social support, impediment in daily living activities and to identify factors affecting impediment in elderly farmer' daily living activities. Methods: The participants were 128 elderly farmers who had received nerve block. Data were collected using a structured questionnaire from February to March, 2018. They were analyzed using t-test, ANOVA, pearson's correlation coefficient, and linear multiple regression. Results: The score of low back pain was $6.27{\pm}1.69$ (10 points), that of social support $2.92{\pm}0.76$ (1~5 points), and that of impediment in activity of daily living $2.01{\pm}0.82$ (0~5 points). Factors affecting impediment in activity of daily living were found to include age (p=.017), daily hours of farm work (p<.001), fear for the nerve block (p<.001), low back pain (p<.001), and social support (p<.001); the explanatory power of these variables was 58.8%. Conclusion: This study has found the controllable factors affecting impediment in activity of daily living among the rural elderly engaging in farm work include low back pain, social support, and daily farming hours. Therefore, to reduce impediment in activity of daily living among them, it is necessary to develop nursing interventions that can improve impediment in activity of daily living through reduction of daily farming hours using local resources. It is also desirable to improve their health status by reducing low back pain, and develop and apply social supports with health education programs that fit the local resources and the needs of the rural elderly.

Estimating excess post-exercise oxygen consumption using multiple linear regression in healthy Korean adults: a pilot study

  • Jung, Won-Sang;Park, Hun-Young;Kim, Sung-Woo;Kim, Jisu;Hwang, Hyejung;Lim, Kiwon
    • Korean Journal of Exercise Nutrition
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    • v.25 no.1
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    • pp.35-41
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    • 2021
  • [Purpose] This pilot study aimed to develop a regression model to estimate the excess post-exercise oxygen consumption (EPOC) of Korean adults using various easy-to-measure dependent variables. [Methods] The EPOC and dependent variables for its estimation (e.g., sex, age, height, weight, body mass index, fat-free mass [FFM], fat mass, % body fat, and heart rate_sum [HR_sum]) were measured in 75 healthy adults (31 males, 44 females). Statistical analysis was performed to develop an EPOC estimation regression model using the stepwise regression method. [Results] We confirmed that FFM and HR_sum were important variables in the EPOC regression models of various exercise types. The explanatory power and standard errors of estimates (SEE) for EPOC of each exercise type were as follows: the continuous exercise (CEx) regression model was 86.3% (R2) and 85.9% (adjusted R2), and the mean SEE was 11.73 kcal, interval exercise (IEx) regression model was 83.1% (R2) and 82.6% (adjusted R2), while the mean SEE was 13.68 kcal, and the accumulation of short-duration exercise (AEx) regression models was 91.3% (R2) and 91.0% (adjusted R2), while the mean SEE was 27.71 kcal. There was no significant difference between the measured EPOC using a metabolic gas analyzer and the predicted EPOC for each exercise type. [Conclusion] This pilot study developed a regression model to estimate EPOC in healthy Korean adults. The regression model was as follows: CEx = -37.128 + 1.003 × (FFM) + 0.016 × (HR_sum), IEx = -49.265 + 1.442 × (FFM) + 0.013 × (HR_sum), and AEx = -100.942 + 2.209 × (FFM) + 0.020 × (HR_sum).

Precise Control of Nutrient Solution and Analysis of Ionic Contribution to EC Reading (양액의 정밀 제어 및 이온의 EC 기여도 분석)

  • Son, Jung-Eek
    • Horticultural Science & Technology
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    • v.16 no.3
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    • pp.352-354
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    • 1998
  • A soilless culture system with the precise control of nutrient solution was developed and the time changes of ionic contribution to EC reading was analyzed. The measuring device designed was able to wash electrodes cleanly and to measure the pH and EC of nutrient solution stably in the box. The nutrient supply system using metering device was also able to control the EC and pH within ${\pm}0.05mS/cm$ and ${\pm}0.05$, respectively. Under the EC control, activity coefficients of all ions decreased with time as ionic concentrations of $SO_4$, Mg and Ca increased due to the selective nutrient absorption by plants. Time changes of ionic contribution to EC reading could be calculated using equivalent ionic conductivities and activity coefficients obtained by numerical analysis.

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Application of Zero-Inflated Poisson Distribution to Utilize Government Quality Assurance Activity Data (정부 품질보증활동 데이터 활용을 위한 Zero-Inflated 포아송 분포 적용)

  • Kim, JH;Lee, CW
    • Journal of Korean Society for Quality Management
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    • v.46 no.3
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    • pp.509-522
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    • 2018
  • Purpose: The purpose of this study was to propose more accurate mathematical model which can represent result of government quality assurance activity, especially corrective action and flaw. Methods: The collected data during government quality assurance activity was represented through histogram. To find out which distributions (Poisson distribution, Zero-Inflated Poisson distribution) could represent the histogram better, this study applied Pearson's correlation coefficient. Results: The result of this study is as follows; Histogram of corrective action during past 3 years and Zero-Inflated Poisson distribution had strong relationship that their correlation coefficients was over 0.94. Flaw data could not re-parameterize to Zero-Inflated Poisson distribution because its frequency of flaw occurrence was too small. However, histogram of flaw data during past 3 years and Poisson distribution showed strong relationship that their correlation coefficients was 0.99. Conclusion: Zero-Inflated Poisson distribution represented better than Poisson distribution to demonstrate corrective action histogram. However, in the case of flaw data histogram, Poisson distribution was more accurate than Zero-Inflated Poisson distribution.