• Journal of Korean Society of Forest Science
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• v.83 no.3
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• pp.372-379
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• 1994

Timber harvesting impacts on soil microbial populations and respiration rates were examined in naturally regenerating trembling aspen(Populus tremuloides Michx.) stands on two contrasting soils, an Omega loamy sand (sandy mixed, frigid Typic Udipsamment) and an Ontonagon clay loam (very fine, mixed Glossic Eutroboralf). Five timber harvesting disturbances were simulated during winter of 1990 and spring of 1991, including commercial whole-tree harvesting(CWH), winter logging trail+CWH, logging slash removal+CWH(LSR), forest floor removal+LSR(FFR), and spring compaction+FFR. Regardless of soil types, total soil respiration rates of each stand decreased slightly or remained the same after harvesting while microbial population increased progressively during the first two years following harvesting. Microbial populations increased more rapidly and constantly at the sandy site than at the clayey site, which may indicate that the soil physical and chemical conditions changed more drastically for microbial activity following timber harvesting at the sandy site than at the clayey site. However, two kinds of treatment applications-three levels of organic matter removal and two levels of compaction-did not result in significant differences in microbial population or total soil respiration rate at each site during the first two post-harvest years. Total soil respiration of the aspen stands, sum of root respiration and microbial respiration, was a poor index for the microbial activity in this study because aspen kept an active root system for the successive root-sprouts even after harvesting, which resulted in a large portion of root respiration in total respiration.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7656-7666
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• 2015

The purpose of this study was to explore the determinants of subjective happiness among Korean adolescents and to supply basic data for enhancing to subjective happiness among Korean adolescents. This study used the 2014 Korean Youth Health Risk Behavior On-lin Survey data. It conducted a secondary data analysis of 72,060 cases. It conducted frequency analysis, t-test, ANOVA and multiple regression analysis by SPSS 18.0. Although various independent variables influenced on emotional support(t=44.335, p<,001), gender(t=27.730, p<.001), grade(t=25.347, p<.001), economic status(t=-25.345, p<.001), living arrangement(t=-6.158, p<.001), school record(t=-7.512, p<.001), father's educational status(t=-2.378, p<.001), subjective health status(t=46.062, p<.001), depression(t=-23.837, p<.001), sleep(t=19.871, p<.001), level of stress(t=-78.685, p<.001), alcohol(t=-13.481, p<.001) and drug use(t=-2.671, p<.01), smoking(t=-11.988, p<.001), breakfast(t=4.443, p<.001), activity(t=4.757, p<.001) were key factors of subjective happiness among Korean adolescents. The findings of this study were as follow: male middle students, who had emotional support, higher economic status, school record and father's educational level, living with family showed higher levels of subjective happiness. It also having good subjective health status, not depressed, more sufficient sleep, lower stress, no experience of drinking, smoking and drugs, more physical activity and having breakfast showed higher levels of subjective happiness.

• 한국노년학
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• v.39 no.4
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• pp.977-996
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• 2019

The current study aimed to examine the gender differences in trajectories of nine successful aging indicators (chronic disease, depression, activities of daily living, instrumental activities of daily living, mini mental state examination, social activity, personal contact, health satisfaction, and general life satisfaction) with age, controlling the effect of education. The data were from the Korean Longitudinal Study of Aging, which had been conducted biennially from 2006 to 2016. The sample included 822 men and 1,236 women who responded to all of the panel surveys and were 65 years old or above in 2006. Multilevel modeling analyses showed that older men had fewer chronic diseases; lower levels of depression; higher levels of activities of daily living, cognitive function, and social activity; and better perceived health satisfaction and general life satisfaction at age 65 years compared to women. However, both men and women showed increase in the number of chronic diseases and depression level, and decrease in physical, cognitive, and social functions with age. In addition, perceived health and life satisfaction also decreased after the age of 65. The trajectories of most of the indicators were non-linear, and markedly increased or decreased around mid-70s. Study limitations and implications were further discussed.

• Journal of Community Nutrition
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• v.5 no.1
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• pp.21-28
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• 2003

A study was conducted to investigate the anthropometric indices, fat distribution, eating habits and levels of daily physical activity based on the body mass index (BMI ; kg/㎡) of 180 female college students. This stady was based on survey 2001 using a questionnaire. The results are as follow ; The mean age, height, weight and BMI were 20.41 ${\pm}$ 1.82 years, 161.86 ${\pm}$ 4.51cm, 53.49 ${\pm}$ 7.02kg, and 20.43 ${\pm}$ 2.65kg/㎡, respectively. The group with BMI of under 20 (the lean group) comprised 48.9% : the group with BMI of 20 to 25 (the normal group) comprised 44.4% and the group with BMI of over 25 (the obese group) comprised 6.7% of the subjects. Even though the lean and the normal groups were determined according to BMI. 12.5% of the lean group and 31.3% of the normal group had more than 25% body fat. Of the students, 11.5% of the lean group, 25.0% of the normal group and 58.3% of the obese group had of more than 0.8 waist/Hip Ratio (WHR). The medical problems suffered by the subjects were constipation (24.4%), gastroenteritis (20.6%), anemia(15.0%) and edema(13.3%), which was a result of their eating habits. Out of all the subjects, 27.2% ingested their meals irregularly, 74.4% skipped breakfast, and 92.4% of the lean group, 89.2% of the normal group and 81.8% of the obese group ingested snacks on a daily basis. Their favorite types of snacks were cookies breads and cakes (33.7%), spicy sliced rice cakes pork sausage and boiled fish cakes (18.5%), fruits (15.2%), juices and sodas (13.5%) and hamburgers and pizzas (3.9%). Their consumption of high calorie and processed foods was high, Of the subjects, 38.9% ate out daily. 45.1% had tried weight loss. Those with large upper bodies comprised 11.5%, large intermediate bodies 18.5% and large lower bodies 69.0%. Most of the students were dissatisfied with their body snaps. Of the subjects, 95.1% exercised irregularly. Daily physical activity tended to increase significantly with an increase in BMI : the lean group's average energy consumption was 1509.40㎉ the normal group's was 1792.21㎉ and the obese group's was 2334.63㎉, which were below the recommended value. This study suggests that the maintenance of an ideal weight, the improvement of eating habits and adequate exercise are needed for female college students to improve their health and nutritional status. (J Community Nutrition 5(1) 21∼28, 2003)

• Nutrition Research and Practice
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• v.7 no.3
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• pp.224-232
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• 2013

The objective of this study is to identify the dietary patterns associated with the risk of hypertensions among Korean adults using data from the Korean National Health and Nutrition Examination Survey (KNHANES, 2008-2010). This study analyzes data from 11,883 subjects who participated in the health and nutrition survey, aging from 20 to 64 years. We performed factor analysis based on the weekly mean intake frequencies of 36 food groups to identify major dietary patterns. We identified three major dietary patterns in both sexes, namely "traditional", "western" and "dairy and carbohydrate" patterns. Participants in the highest quartile of western pattern scores had significantly higher blood pressure, serum total cholesterol, and triglyceride levels than those in the lowest quartile. Although not statistically significant, a trend (P for trend = 0.0732) toward a positive association between the western dietary pattern and hypertension risk was observed after adjustments for age, sex, education, income, body mass index (BMI), smoking, physical activity, and energy intake. The dairy and carbohydrate pattern was inversely related with BMI and blood pressures and positively associated with serum high-density lipoprotein (HDL)-cholesterol. After adjusting the age, sex, education, income, BMI, smoking, physical activity and energy intake, the dairy and carbohydrate pattern showed inverse associations with hypertension prevalence (OR = 0.64, 95% CI = 0.55-0.75; P for trend < 0.0001). Intakes of fiber, sodium, and antioxidant vitamins were significantly higher in the top quartile for the traditional pattern than in the lowest quartile for the traditional pattern (P for trend < 0.0001). Intakes of fiber (P for trend < 0.0001), calcium (P for trend < 0.0001), retinol (P for trend = 0.0164), vitamin $B_1$ (P for trend = 0.001), vitamin $B_2$ (P for trend < 0.0001), niacin (P for trend = 0.0025), and vitamin C (P for trend < 0.0001) were significantly increased across quartiles for the dairy and carbohydrate pattern whereas sodium (P for trend < 0.0001) intake was decreased for this pattern. In conclusion, the dairy and carbohydrate pattern may be associated with a reduced risk of hypertension whereas the western pattern may be associated with an increased risk of hypertension among Korean adults.

• Biomedical Science Letters
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• v.13 no.1
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• pp.25-32
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• 2007

The purpose of this study was to investigate the effect of the high voltage pulsed Current (HVPC) stimulation on the healing rate and the proliferative activity of keratinocytes and IGF-I mRNA expression of an incisional wound in rat skin. Twenty male Sprague-Dawley rats ($265{\sim}290g$) were randomly divided into HVPC (n=10) and control group (n=10). Rats received 10 mm length of full-thickness incision wound on the back under the anesthesia. The HVPC group received electrical stimulation with a Current intensity of 50 V at 100 pps for a duration of 30 minutes, while the control group was given the same treatment without electricity for a week. Polarity was negative in first three days and positive thereafter. The wound length was measured and evaluated as percentage. The mean number of nucleolar organizer regions (NORs) per nucleus and level of IGF-I mRNA expression were calculated. The mean percent of wound closure were $51.17{\pm}17.76%$ and $80.71{\pm}11.91%$, respectively, in the sham treated control and HVPC stimulated groups (t=-4.308, P<0.001). The mean NOR number per nucleus of the keratinocytes in the control and HVPC group were $1.85{\pm}0.20$ and $2.70{\pm}0.23$, respectively (t=8.638, P<0.001). The IGF-I mRNA level were $0.76{\pm}0.44$ and $1.32{\pm}0.41$, respectively, in the control and HVPC stimulated wounds (t=2.906, P<0.01). There was a positive correlation between the mean NOR number per nucleus and IGF-l mRNA level with a Pearson product moment correlation coefficient of 0.72 (P<0.05). These findings suggest that the HVPC may activate the rRNA of the basal keratinocytes and upregulate the IGF-I mRNA levels by alteration of the electrical environment, and it may increase proliferative activity of the keratinocytes in the skin wound of the rat.

• Food Science and Preservation
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• v.16 no.4
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• pp.525-533
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• 2009

To explore cattail pollen powder as a functional food ingredient, we analyzed the general components of pollen powder, tested changes in the physical properties of dough containing the powder, and investigated the process ability of powder-containing dough in bread making by adding 3%, 6%, or 9% by weight of pollen powder to wheat flour. Cattail pollen powder consisted of (all w/w) 12.7-13.2% water, 15.7-17.8% crude protein, 1.3% crude fat, 7.5-7.7% free sugar, 14.7-18.6% crude fiber, 3.4-4.9% pollen, and 49.7-55.9% soluble nitrogen-free extract (NFE). Analysis of the physical properties of dough mixed with pollen powder showed that as more pollen powder was added, the absorption rate increased, but dough stability decreased. With increasing levels of cattail pollen powder, the falling number decreased, and amylase activity increased. Fermentability was highest in dough made with 3% by weight of pollen powder, and the bread product made from such dough had the greatest volume. As more cattail pollen powder was added, the moisture activity in dough tended to decrease to a greater extent than seen in control dough, and this tendency increased with time. We found that longer storage periods were associated with greater hardness and springiness, which indicated degradation in product quality. Therefore, it is suggested that bread products containing cattail pollen powder should be consumed within 3 days of preparation. In a taste survey, bread baked with 3% (w/w) cattail pollen powder scored highest in all questionnaire items.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.48 no.2
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• pp.127-137
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• 2011

We have developed a wearable device that can convert sensor data into real-time step counts and activity levels. Sensor data on gait were acquired using a triaxial accelerometer. A test was performed according to a test protocol for different walking speeds, e.g., slow walking, walking, fast walking, slow running, running, and fast running. Each test was carried out for 36 min on a treadmill with the participant wearing a portable gas analyzer (K4B2), an Actical device, and the device developed in this study. The signal vector magnitude (SVM) was used to process the X, Y, and Z values output by the triaxial accelerometer into one representative value. In addition, for accurate step-count detection, we used three algorithms: an heuristic algorithm (HA), the adaptive threshold algorithm (ATA), and the adaptive locking period algorithm (ALPA). A regression equation estimating the energy expenditure (EE) was derived by using data from the accelerometer and information on the participants. The recognition rate of our algorithm was 97.34%, and the performance of the activity conversion algorithm was better than that of the Actical device by 1.61%.

• Journal of Nutrition and Health
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• v.38 no.5
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• pp.352-363
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• 2005

The previous extensive in vitro studies on the antioxidative activities of a number of Korean grains, vegetables, seaweeds and mushrooms, and the various combinations of these food source exhibited a wide range of antioxidative activities, and four food mixtures composed of 5 kinds of foods (5A, 5B, 5C and 5D) were designed from 16 selective foods showing. high antioxidant effect, in vitro, to find the good combinations for the meal planning. Mixture 5B or 5C contained very high levels of total flavonoid and polyphenol, and ethanol extract from 5A, 5B or 5C showed very strong inhibitory effects against in vitro $Fe^{2+}-induced$ lipid peroxidation and ethanol extract from 5B or 5C showed remarkable DPPH radical scavenging effect and lipid peroxide-protein conjugation inhibition effect. And in vivo study was also carried out with two mixtures (5B, 5C). Powders (P5B, P5C) or ethanol extracts (E5B, E5C) of these mixtures were supplemented to Sprague-Dawley rats fed on high fat $(15\%)-high$ cholesterol $(1\%)$ semipurified diet for 5 weeks. The total antioxidant power in serum was significantly higher in P5B, P5C, E5B and E5C groups than in high fat control group, and $ascorbate-Fe^{2+}-induced$ TBARS was significantly lowered by E5B supplementation in rat liver. In liver tissue, Cu, Zn-SOD activity was significantly higher in P5B and E5B groups than in high fat control group, while catalase or GSH-peroxidase (GPx) activity was not changed by any supplementations. In kidney, Cu, Zn­SOD activity was significantly higher in P5B group than in high fat control group, while GPx activity was not changed by any supplementations. Taken together, mixture 5B and 5C showed very strong antioxidative effects both in vitro and in vivo. Therefore, the ingredient Korean foods of 5B and 5C could be recommended to take a lot together for prevention from age-related chronic diseases.

• Applied Biological Chemistry
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• v.43 no.4
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• pp.236-240
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• 2000

Correlations between mitochondrial respiration, glycolysis activity and overall growth activity of rice (Oryza sativa: cv. Dasan) seedlings during low temperature exposure were studied in order to provide insights into the underlying mechanism for the primary phase of chilling injury in plants. Among cellular membranes involved in energy metabolism, only the mitochondrial inner membrane showed not only physical phase transition at ca. $13^{\circ}C$, as monitored by ESR spin label, but also functional phase transition at the same temperature, as assessed by cytochrome c oxidase activity. The main regulatory enzyme of glycolysis, phosphofructokinase, in situ did not suffer phase transition of its activity at least in the $4{\sim}27^{\circ}C$ range. Low temperature caused a significant accumulation of glucose 6-phosphate (G6P) and fructose 6-phosphate (F6P), which disappeared almost completely on rewarming of the seedlings. Temperature profiles of the steady state levels of G6P and F6P revealed the inflection point appearing at around phase transition temperature of the mitochondrial membrane. The results conform to our previous proposition on the mechanism for the early stage events of chilling injury that the accumulation of glycolytic metabolites in cells due to metabolic imbalance at low temperature gives rise to an excess supply of electrons during rewarming period, which, in turn, results in overproduction of active oxygen in mitochondria.