• Korean Journal of Community Nutrition
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• v.18 no.1
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• pp.45-54
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• 2013

This study was conducted to investigate the physical activity pattern, activity coefficient, basal metabolic rate and energy expenditure of female university students. One-day activity diaries were collected from 95 female university students in Seoul. Body composition was measured by Inbody 720. Subjects spent 7 hr 8min on sleeping, 6 hr 31min on studying, 2 hr 50min on physiological activity, 2 hr 3min on leisure, 2 hr 2min on walking and jogging, 1 hr 58 min on commuting and 22min on house chores. The activity coefficient of these subjects was 1.58. The comparison of body composition of subjects according to PAL showed that body weight, body fat mass, arm circumference and arm muscle circumference of physically active group were significantly higher than those of the sedentary group. BMR calculated by Harris-Benedict (H-B) formula and DRI formula and BMR measured by Inbody 720 was 1375 kcal, 1306 kcal and 1209 kcal, respectively. Total energy expenditure (TEE) examined by one-day activity diaries and calculated by H-B formula and estimated energy requirement (EER) formula in DRI was 2102.1 kcal, 2184.4 kcal, and 2164.5 kcal, respectively. The Pearson correlation coefficient between TEE examined by one-day activity diaries and H-B TEE was 0.795 (p < 0.001) while that between TEE examined and DRI EER was 0.604 (p < 0.001). Overall data indicated that female university students seemed to be less active. Therefore it is recommended that universities develop good exercise programs for their students. Further studies are needed to generate more meaningful results with a larger sample size and using machine attached to the body, which are able to detect physical activity more accurately.

• Journal of Microbiology and Biotechnology
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• v.26 no.8
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• pp.1452-1456
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• 2016

Overexpression of the genes encoding phosphoeneolpyruvate carboxykinase (pckA) and NAD-dependent malic enzyme (maeA) facilitates higher intracellular ATP and NAD(P)H concentrations, respectively, under aerobic conditions in Escherichia coli. To verify a hypothesis that higher intracellular energy reserves might contribute to H₂ fermentation, wild-type E. coli strains overexpressing pckA and maeA were cultured under anaerobic conditions in a glucose minimal medium. Overexpression of pckA and maeA enabled E. coli to produce 3-times and 4-times greater H₂ (193 and 284 nmol, respectively) than the wild type (66 nmol H₂). The pckA and maeA genes were further overexpressed in a hydrogenase-3-enhanced E. coli strain. The hydrogenase-3-enhanced strain (W3110+fhlA) produced 322 nmol H₂, whereas the ATP-enhanced strain (W3110+fhlA+pckA) produced 50% increased H₂ (443 nmol). Total H₂ in the NAD(P)H-enhanced strain (W3110+fhlA+maeA) was similar to that in the control strain at 319 nmol H₂. Possible explanations for the contribution of the increased cellular energy reserves to the enhanced hydrogen fermentation observed are discussed based on the viewpoint of metabolic engineering strategy.

• Physical Therapy Rehabilitation Science
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• v.11 no.4
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• pp.478-487
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• 2022

Objective: This study was conducted to analyze the effect of wearable complex muscle support system on energy efficiency during walking in elderly. Design: Cross sectional study Methods: Twenty healthy elderly participated in this study. All subjects performed a 6 minuteswalk test(6MWT) and stair climbing test in dual, slack and no suit conditions. In each condition, oxygen consumption(VO₂), metabolic equivalents(METs), energy expenditure measures(EEm), physiological cost index(PCI), walking velocity and heartrate were measured. Through repeated measured ANOVA, it was investigated whether there was a statistically significant difference in the measurement results between the three conditions. Results: In over-ground walking, VO₂, METs and EEm showed significant differences between no suit and slack conditions(p<0.05). In stair climbing, VO₂ showed significant difference between slack and dual conditions(p<0.05). Also, METs and EEm showed significant differences between no suit and slack, and between slack and dual conditions(p<0.05). Conclusions: Wearing the wearable complex muscle support system for elderly does not have much benefit in energy metabolism efficiency in over-ground, but there is a benefit in stair walking.

• Journal of Nutrition and Health
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• v.29 no.8
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• pp.899-907
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• 1996

This study was conducted to examine how Korean women mange energy metabolism during lactation. Eighteen women recruited were healthy, had normal pregnancies and were required to breast-feed their babies exclusively for at least 12wks. During the study period, all subjects were visited and interviewed five times : 3d, 9d, 4wk, 8wk, and 12wk lactation. Body composition variables were analyzed by a bioelectrical impedance method, energy intakes were assessed by using the inventory-weighing method, energy expenditure were determined by recording daily activities, and milk energy output was investigated from the amount of milk production and the gross energy content of milk. The subjects consumed less energy than current recommended allowance all over the study period, but compatible with fairly adequate lactational performance. They responded the additional energy stress of lactation by enhancing metabolic efficiency, increasing energy intakes, reduction physical activities and mobilizing body reserves. Another finding in this study was that the reduction in body fat-free mass may be the one way that women meet the energy demands of lactation like the reduction in body fat mass. The results from this study suggest that current recommended additional energy need during lactation, 2.09MJ/d(500kcal/d), is too high for healthy Korean women. Our data also indicate that the changes of body composition and energy balance at earlier postpartum are extremely different from those at later periods.

• Korean Journal of Clinical Laboratory Science
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• v.47 no.4
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• pp.324-331
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• 2015

Thyroid hormones are essential for cellular energy homeostasis and regulation by interacting with the sympathetic nervous system. This study was conducted to investigate the relationship between thyroid hormone and risk factors of metabolic syndrome for medical checkups of male patients. The study subjects were 12,250 males between 20~80 years old who visited the hospital for a health check-up at one General Hospital in Gyeonggi-do during the period of January 2011 to December 2013. According to the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI), the metabolic syndrome criteria is defined as the presence of 3 or more risk factors. FT4 was lower in the metabolic syndrome group than in the normal group (p<0.001). The level of FT4 decreased as the levels of abdominal obesity (p=0.001), hypertriglyceridemia (p<0.001), blood pressure (p=0.005) and blood glucose (p=0.005) increased. The TSH level increased hypertriglyceridemia (p=0.047). FT4 had an influence on the waist circumference and triglyceride (p<0.001). HbA1c, insulin, HOMA-IR, hs-CRP were higher in the lowest quartile than in the highest quartile (p<0.001). FT4 had effects on the waist circumference and triglyceride, but TSH had no effect on metabolic syndrome risk factors. The metabolic syndrome was lower in the highest quartile of FT4 than in its lowest quartile.

• Nutrition Research and Practice
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• v.8 no.2
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• pp.177-182
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• 2014

BACKGROUND/OBJECTIVES: Irisin, a newly identified hormone, is associated with energy homeostasis. We investigated whether aged garlic extract (AGE) and exercise training intervention could improve body weight, insulin sensitivity, skeletal muscle fibronectin domain containing protein 5 (FNDC-5) levels, and plasma irisin in high-fat diet (HFD). MATERIALS/METHODS: Male Sprague Dawley rats were fed a ND (normal diet, n=5) or HFD (n=28) for 6 weeks. After 6 weeks, all rats were divided into 5 groups for the next 4 weeks: ND, (normal diet, n=5), HFD (high-fat diet, n=7), HFDA (high-fat diet + aged garlic extract, n=7), HFDE (high-fat diet + exercise, n=7), and HFDEA (high-fat diet + exercise + aged garlic extract, n=7). Exercise groups performed treadmill exercises for 15-60 min, 5 days/week, and AGE groups received AGE (2.86 g/kg, orally injected) for 4 weeks. RESULTS: Significant decreases in body weight were observed in the ND, HFDE, and HFDEA groups, as compared with the HFD group. Neither intervention affected the masses of the gastrocnemius muscle or liver. There were no significant differences in glucose levels across the groups. The homeostatic model assessments of insulin resistance were significantly higher in the HFD group, as compared with the ND, HFDA, HFDE, and HFDEA groups. However, skeletal muscle FNDC-5 levels and plasma irisin concentrations were unaffected by AGE or exercise in obese rats. AGE supplementation and exercise training did not affect skeletal muscle FNDC-5 or plasma irisin, which are associated with insulin sensitivity in obese rats. CONCLUSION: Our results suggest that the protection against HFD-induced increases in body fat/weight and insulin resistance that are provided by AGE supplementation and exercise training may not be mediated by the regulation of FNDC-5 or irisin.

• Journal of Nutrition and Health
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• v.26 no.4
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• pp.390-404
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• 1993

The purpose of this paper is to determine the percentage of body fat by measurement of skin-fold thickness of the triceps and the subscapular area to investigate the relationship between the daily energy intake and expenditure among obese women and nonobese women based on the percentage of body fat and age. This survey included 422 females in Cheju. 1) The age distribution of the 422 females surveyed was : 26.8% were in their 20's, 20.6% in their 30's, 21.3% in their 40's, 19.0% in their 50's and 12.3% were above 60 years of age. The 422 females consisted consisted of 78% housewives, 12.8% college student and 9.2% single working women. 2) The average height and weight of the surveyed women were respecitively 159.0$\pm$4.2cm and 56.0$\pm$7.2kg, the percentage of body fat of the surveyed women was 24.8$\pm$9.8%, and the BMI of those surveyed was 22.7$\pm$2.7. If higher than 30% body fat was defined as being obese, 15.6% of the surveyed women were assessed to be obese. 3) Total daily food consumption and energy intake of the group of women aged 60 and older was significantly small. Food consumption and nutrient intake of obese women was greater than that of the nonobese group, but not significant. Carbohydrate intake of the obese group in their 40's was significantly higher than the nonobese group. Total food consumption, energy and carbohydrate intake of the obese group in their 50's was significantly higher than the nonobese group. Vegetable intake of the obese group in their 60's and older was significantly higher than the nonobese group. 4) The total time of physiological activity of women aged 60 and older was significantly higher than for the other age groups and the total work time was significantly lower. The total work time of women in their 20's was not lower than the other groups. Considering the low energy expenditure of physical activity for women in their 20's, they appeared to have light activity. However, there was not a significant difference in the physical activity time among middle aged women groups(from 30 to 50). The entire energy expenditure of the obese group was greater than the nonobese group. However, the energy expenditure per body weight in the obese group was significantly less than that of the nonobese group in terms of the basal metabolic rate in consideration of the fat free mass. 5) There was a positive correlation between the percentage of body fat and the factors of age, sleeping time, total time of physiological activity, housework time, time spent watching TV, energy expenditure, energy intake, carbohydrate and cereal consumption. On the other hand, the percentage of body fat was negatively correlated with energy expenditure per body weight based on the basal metabolic rate in consideration of the free mass.

• Plant Biotechnology Reports
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• v.5 no.3
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• pp.197-215
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• 2011

Plant tissue culture and molecular biology techniques are powerful tools of biotechnology that can complement conventional breeding, expedite crop improvement and meet the demand for availability of uniform clones in large numbers. Jatropha curcas Linn., a non-edible, eco-friendly, non-toxic, biodegradable fuel-producing plant has attracted worldwide attention as an alternate sustainable energy source for the future. This review presents a consolidated account of biotechnological interventions made in J. curcas over the decades and focuses on contemporary information and trends of future research.

• International Journal of Precision Engineering and Manufacturing
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• v.9 no.2
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• pp.23-27
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• 2008

As a biofuel source, direct photosynthetic/metabolic biofuel cells (DPBFC) use cyanobacteria whose photosynthesis and metabolization reactions can convert light energy to electricity, In our previous work, we fabricated a prototype micro-DPBFC that could generate a peak current density of $36{\mu}A/cm^{2}$ and a maximum power density of $270nW/cm^{2}$. In this study, we improve on the previous results by using carbon micro electromechanical systems (C-MEMS), formed from the pyrolysis of patterned photoresist, to fabricate carbon electrodes of an arbitrary shape and controlled porosity to increase the surface area. With these new C-MEMS electrodes, the maximum power density of the micro-DPBFC was $516nW/cm^{2}$, a performance twice as good as the results of our previous work.

• Journal of Marine Bioscience and Biotechnology
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• v.6 no.1
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• pp.8-16
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• 2014

Macroalgae has been strongly touted as an alternative biomass for biofuel production due to its higher photosynthetic efficiency, carbon fixation rate, and growth rate compared to conventional cellulosic plants. However, its unique carbohydrate composition and structure limits the utilization efficiency by conventional microorganisms, resulting in reduced growth rates and lower productivity. Nevertheless, recent studies have shown that it is possible to enable microorganisms to utilize various sugars from seaweeds and to produce some energy chemicals such as methane, ethanol, etc. This paper introduces the basic information on macroalgae and the overall conversion process from harvest to production of biofuels. Especially, we will review the successful efforts on microbial engineering through metabolic engineering and synthetic biology to utilize carbon sources from red and brown seaweed.