• Asian-Australasian Journal of Animal Sciences
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• 제22권5호
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• pp.747-755
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• 2009

The feed resource for animals is a major cost determinant for profitability in livestock production enterprises, and thus any effort at improving the efficiency of feed use will help to reduce feed cost. Feed conversion ratio, expressed as feed inputs per unit output, is a traditional measure of efficiency that has significant phenotypic and genetic correlations with feed intake and growth traits. The use of ratio traits for genetic selection may cause problems associated with prediction of change in the component traits in future generations. Residual feed intake, a linear index, is a trait derived from the difference between actual feed intake and that predicted on the basis of the requirements for maintenance of body weight and production. Considerable genetic variation exists in residual feed intake for cattle and pigs, which should respond to selection. Phenotypic independence of phenotypic residual feed intake with body weight and weight gain can be obligatory. Genetic residual feed intake is genetically independent of its component traits (body weight and weight gain). Genetic correlations of residual feed intake with daily feed intake and feed conversion efficiency have been strong and positive in both cattle and pigs. Residual feed intake is favorably genetically correlated with eye muscle area and carcass weight in cattle and with eye muscle area and backfat in pigs. Selection to reduce residual feed intake (excessive intake of feed) will improve the efficiency of feed and most of the economically important carcass traits in cattle and pigs. Therefore, residual feed intake can be used to replace traditional feed conversion ratio as a selection criterion of feed efficiency in breeding programs. However, further studies are required on the variation of residual feed intake during different developmental stage of production.

• Nutrition Research and Practice
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• 제5권4호
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• pp.329-336
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• 2011

Obesity contributes to an increased risk for chronic diseases, including diabetes, cardiovascular diseases, and certain types of cancer. The prevalence of obesity has increased in Korea. We compared the clinical and dietary characteristics of obese adults (n = 30, 17 men and 13 women, mean age 29.9) to those with a normal weight (n = 15, 8 men and 7 women, mean age 26.5). We determined lipid profiles, fasting blood sugar (FBS), blood pressure, and serum free fatty acid (FFA). Dietary intake was estimated using a food frequency questionnaire (FFQ) and a 3-day dietary record. Exercise patterns and average alcohol intake were determined. The average body mass index was 28.3 kg/$m^2$ in the obese and 21.2 kg/$m^2$ in the normal weight groups. The obese group had significantly higher levels of total cholesterol, LDL cholesterol, and triglycerides, lower levels of HDL cholesterol, and higher blood pressures compared to the normal weight group. FBS was not significantly different between the two groups. The obese group had significantly more subjects with metabolic syndrome (26.7%) compared to the normal weight group (0%). Serum FFA levels tended to be higher in the obese (P = 0.087). No significant difference in caloric intake was observed between the two groups. No differences in carbohydrate, protein, or fat intake between two groups were observed from the FFQ. However, results from the 3-day dietary record showed that the percentage of energy from fat was significantly higher in the obese group. The frequency and amount of exercise did not differ between the two groups. Alcohol consumed per drinking episode was significantly higher in the obese group. These results confirm that excessive weight is associated with disturbances in lipid metabolism in these fairly young and otherwise healthy adults. Dietary factors, including higher fat intake and alcohol consumption, seem to be contributing to the obesity of these subjects.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제18권2호
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• pp.100-107
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• 2015

Purpose: We investigated the iron status of very low birth weight infants receiving multiple erythrocyte transfusions during hospitalization in the neonatal intensive care unit (NICU). Methods: We enrolled 46 very low birth weight infants who were admitted to the Kyungpook National University Hospital between January 2012 and December 2013. Serum ferritin was measured on their first day of life and weekly thereafter. We collected individual data of the frequency and volume of erythrocyte transfusion and the amount of iron intake. Results: A total of 38 (82.6%) of very low birth weight infants received a mean volume of $99.3{\pm}93.5mL$ of erythrocyte transfusions in NICU. The minimum and maximum serum ferritin levels during hospitalization were $146.2{\pm}114.9ng/mL$ and $456.7{\pm}361.9ng/mL$, respectively. The total volume of erythrocyte transfusion was not correlated to maximum serum ferritin concentrations after controlling for the amount of iron intake (r=0.012, p=0.945). Non-transfused infants took significantly higher iron intake compared to infants receiving ${\geq}100mL/kg$ erythrocyte transfusion (p<0.001). Minimum and maximum serum ferritin levels of non-transfused infants were higher than those of infants receiving <100 mL/kg erythrocyte transfusions (p=0.026 and p=0.022, respectively). Infants with morbidity including bronchopulmonary dysplasia or retinopathy of prematurity received a significantly higher volume of erythrocyte transfusions compared to infants without morbidity (p<0.001). Conclusion: Very low birth weight infants undergoing multiply erythrocyte transfusions had excessive iron stores and non-transfused infants also might had a risk of iron overload during hospitalization in the NICU.

• 대한지역사회영양학회지
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• 제23권5호
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• pp.431-443
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• 2018

Objectives: Normal weight obesity (NWO) is defined as excessive body fat in the context of a normal body mass index (BMI). This condition carries a greater risk of developing noncommunicable chronic disease and has been associated with early inflammation. This study was conducted to compare the anthropometric measurements, eating behaviors, and blood clinical indices among four groups: underweight, normal, normal weight obesity and obesity. Methods: The subjects included 215 female college students. A questionnaire was administered regarding general characteristics, dietary behaviors, food consumption frequency. Anthropometric measurements and blood clinical indices were also investigated. Results: The average BMI, body fat percentage, waist circumference, fat-free mass, and muscle mass were highest in the obesity group (p<0.05). Most subjects had tried to lose weight and perceived that their health was worse than before they became college students. The ratio of students in the NWO group who thought their health was very poor was significantly higher than in the other three groups (p<0.05). The obesity and NWO groups seemed to eat more and their eating speed was significantly faster than the other groups (p<0.001). The consumption frequency of caffeinated beverages was significantly higher in the NWO group than in the other three groups (p<0.01). WBC was significantly higher in the obesity group (p<0.05). Serum levels of TG and total cholesterol were also significantly higher in the obesity group (p<0.05). Serum GPT was significantly higher in the obesity group (p<0.05) while BUN level was highest in the NWO group (p<0.05). Conclusions: The obesity group showed the most health problems while the NWO group seemed relatively healthy. However, NWO can lead to problems such as metabolic syndrome and cardiovascular disease in later life if poor dietary habits are maintained. Therefore, education in appropriate eating habits is needed for these subjects.

• Animal Bioscience
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• 제34권1호
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• pp.102-108
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• 2021

Objective: The objective of this study was to investigate the influence of dietary lead (Pb) supplementation and feeding period on growth performance, organ weight, and Pb accumulation in pigs. Methods: In a 56-day feeding experiment, a total of 48 barrows with initial body weight 10.4±0.6 kg were allotted to 2 dietary treatments (0 and 200 mg/kg of supplemental Pb) in a completely randomized design with 6 replicates. Body weight and feed intake were recorded to calculate growth performance. At the end of each 14 day-period (on days 14, 28, 42, and 56), an animal was randomly selected from each pen and slaughtered to collect blood samples, hair samples, left 5th rib, heart, liver, kidneys, lungs, and longissimus dorsi muscle samples. Results: Average daily gain and average daily feed intake were reduced (p<0.05) by supplemental Pb during the day 42 to 56. Relative kidney weight to body weight was linearly increased with increasing feeding period in pigs fed the Pb-supplemented diet, but not in pigs fed the control diet (p<0.05). The Pb concentrations in hair, left 5th rib, kidneys, and lungs were linearly increased with longer feeding period in pigs fed the Pb-supplemented diet, but not in pigs fed the control diet (p<0.01). Conclusion: Dietary Pb supplementation caused growth retardation and Pb accumulation in most organs, particularly in hair, bone, and kidneys in a time-dependent manner.

• 대한지역사회영양학회지
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• 제12권6호
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• pp.724-741
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• 2007

This study was carried out to investigate the body weight controls and eating disorders of university students in Gunsan. The subject of the present study included 229 male students (53.8%) and 197 female students (46.2%), totalling 426 students from Kunsan University. The subjects consisted of 56 underweight (13.1%), 265 with normal weight (62.2%), and 105 overweight (24.6%). Especially, in females, 20.8% of them were underweight, which is 6.6% higher than males, showing a significant difference (p<0.001). Regarding body image, 21.8% of the males thought they were fat, while 40.6% of the females thought they were fat. Regarding the perceived body type, shown in the difference between their own size and the ideal size, males recorded 0.03, while females recorded 1.75, showing a major significant difference (p<0.001). Regarding body satisfaction, 33.2% of the males were unsatisfied, while 52.8% of the females were unsatisfied (p<0.001). The social expectations of the male subjects' sizes and weights recorded 2.04, while that of females recorded -2.51, showing that people's opinions expected the female subjects' bodies to be thinner (p<0.001). Additionally, the social expectation of the subjects' weight control recorded an average of 15.22 (13.92 for males, 16.73 for females), showing that the female subjects' felt that people's opinions wished them to lose their weight (p<0.001). Regarding the recognition on weight control, interested males were 49.4%, while interested females were 86.8%, showing the females superior rate (p<0.001). The beliefs in relation to weight control recorded an average of 62.01, with the score of females of 67.89 being significantly higher than that of males which was 56.96. The subjects showed a relatively positive response towards weight control (p<0.001). EAT-26 score was employed to determine the eating attitudes in relation to gender. Here, the final score of males was 15.46, which was significantly lower than that of females, which was 22.21 (p<0.001). Furthermore, regarding the score of eating attitudes in relation to obesity index, the eating disorder scale scores on the questions related to bulimia and diets to lose weight as weight increases were high. However, the eating disorder scale score on oral control, which actually controls food, was low. To control the expansion of excessive weight control attempts and their side effects, the recognition of the students' body types needs to be corrected, and nutrition education programs on eating habits and eating disorders to foster proper weight loss are deemed necessary.

• 한국지반공학회논문집
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• 제23권3호
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• pp.25-40
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• 2007

얕은 터널의 개착식 터널 라이닝에 발생하는 과잉토압은 라이닝의 변형과 손상을 유발하는 역학적 주요인자들 중의 하나이며(Kim, 2000), 과잉토압은 되메움토의 다짐불량, 자중에 의한 압밀, 강우의 침투에 의한 다짐, 차량에 의한 진동 등에 의해 발생할 수 있다(Komiya et al., 2000; Taylor et al., 1984; Yoo, 1997). 터널 라이닝에 발생하는 토압을 구하기 위한 많은 시험이 행해졌지만, 부등침하와 과잉토압을 줄일 수 있는 보강대책을 수립하기 위한 사례는 없다. 본 연구는 모래 지반에 $1.0D\sim1.5D$ 깊이에 개착식으로 시공하는 원형의 강성 터널에 작용하는 토압에 관한 것으로 진동다짐의 영향을 모형실험에서 충분히 반영하기 위하여 100Hz의 진동주파수를 사용하였다. 본 연구에서는 개착식 터널 라이링에 작용하는 부등침하와 과잉토압을 줄이기 위해서 지오텍스타일 매트를 설치하였다. 지오텍스타일 매트의 보강에 의한 부등침하와 토압의 감소효과를 확인하기 위해 실내모형실험을 수행하였다. 실내모형실험에서 토피, 매트 보강형태, 절취면의 거칠기 등을 달리하여 가장효과적인 방법을 구하였다. 절취면의 거칠기 달리하기 위해 사면에 사포#100, 사포#400과 acetate 부착하였습니다. 무보강과 매트 보강에 대한 모형실험을 실시하여 구한 토압을 비교하여 매트 보강효과를 살펴보았으며, 사진분석법(Park, 2003)을 이용하여 지반의 변형을 분석하였다.

• 한국수산과학회지
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• 제24권1호
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• pp.9-20
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• 1991

광양만에 분포하는 미고결 퇴적충의 물성특성을 Core 시료를 채취하여 분석하였다 퇴적상태의 특성을 지시하는 퇴적층의 공극율이 퇴적깊이에 따라 일정한 변화를 나타내지 않으며, 이는 자체하중에 의한 자연적 압밀이 매우 미세한 것을 나타내고 있다. 조석에 의한 해수면 변동이 퇴적층 거동에 미치는 영향을 수치해석적으로 분석한 결과, 퇴적층에 형성되는 공극수압이 이토층의 낮은 투수계수에 기인하여 해수면 변동에 따른 표층 수압변화보다 느리게 진행되고 있다. 따라서, 최소 해수면시점에 발생되는 공극수압이 해수압에 의한 역학적 응력보다 커서 퇴적층의 유효응력이 인장력으로 반전되며 일정깊이에서의 현장유효응력도 인장력상태(quick sand condition)인 것으로 나타난다. 이러한 현상은 퇴적물조직의 재구성이 내부적으로 발생될 수 있는 가능성을 제시해 주고 있다. 모래질이토층(sandy mud layer)이 이토층내에 존재할 경우에도 이토층과의 경계부분에서 인장력강태의 현장유효응력(quick sand condition)이 발생한다. 이는 퇴적물 재구성작용에 의해 모래질 입자가 표층에서 하부층으로 하강될 수 있는 역학적 이론근거를 제시해 주고 있으며, 본 연구결과에 의하면 모래질 입자들이 약 40cm 깊이에 하강될 때까지 quick sand condition이 형성된다.

• Journal of Nutrition and Health
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• 제40권4호
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• pp.385-394
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• 2007

The purpose of this study was to determine the zinc status of preschool children in Ulsan. The study was conducted in 95 children aged 3 to 6 years by investigating the anthropometric indices and assessing the biochemical analysis. The blood was analysed to assess serum zinc and alkaline phosphatase. And a questionnaire for dietary intakes using 24-hr recall method were performed by mothers of 95 subjects. The dietary intakes of children were analysed to determine the prevalence of inadequate and excessive intakes of zinc with Dietary Reference Intakes for Koreans (KDRIs). WHL (Weight-Length Index) and Kaup index were used to define obesity. The overall prevalence of overweight and obese subjects were 14.7% and 6.3% by WHL, were 15.8% and 13.7% by Kaup index. The mean intakes of zinc by children aged 3${\sim}$5y and 6y were 5.5 ${\pm}$ 1.4 mg/d (75.7% RDA) and 6.7 ${\pm}$ 2.0 mg/d, respectively, that was the level exceeding the estimated average requirement (EAR) and the recommended intake (RI) of Korean Dietary Reference Intakes. Less than 1.3% and 7.9% of children had usual zinc intakes below EAR and RI of KDRIs, respectively. The percentages of children with intakes exceeding the tolerable upper intake level (UL) were 2.6%. The zinc nutritional status by biological assay was found that mean serum zinc and alkaline phosphatase (ALP) of total subjects were 64.0 ${\pm}$ 8.4 ${\mu}$g/dl and 72.8 ${\pm}$ 14.9 U/L, there was not a significant difference between boys and girls. The range of serum zinc level was 45${\sim}$89 ${\mu}$g/dl and children with a low serum zinc concentration by several cut-off points were 18.9${\sim}$55.8%, especially. Serum zinc level was positively correlated to the intakes of calorie, calcium, fiber, iron, zinc, zinc/kg and height (p<0.001). Serum ALP was positively correlated height, weight and WLI. The zinc intake of children aiso showed a positive correlation with height and weight. These results indicate that there were significant correlations between the zinc status and growth of preschool children. Preschool children in Ulsan have dietary zinc intakes that exceed the new DRIs. The present level of intake does not seem to pose a health problem, but if zinc intakes with fortified foods and supplements were considered, the amount of zinc consumed by children may become excessive.

• 펄프종이기술
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• 제41권2호
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• pp.13-19
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• 2009

In order to produce high quality paper at the lowest cost in high speed, typically various polyelectrolytes as retention aids were used. Retention systems such as single polymer system, dual polymer system, and microparticle system were used. The objective of this study was to analyze the changes of retention, drainage, formation and fracture toughness depending on types of retention system, molecular weight of C-PAM and dosage sequences of agents. When single polymer system was applied, retention was increased with poor formation and drainage. When common microparticle system(C-PAM/bentonite) was used, high molecular weight PAM gave high retention and fast drainage, but poor formation. When the microparticle system with reverse dosage sequence(bentonite/C-PAM) was used, low molecular weight PAM gave high retention, fast drainage and good formation. When various retention agents were applied, fracture toughness was increased than that of blank. When using high molecular weight PAM and consequently causing excessive flocculation, fracture toughness was decreased.