• Journal of Nutrition and Health
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• v.14 no.4
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• pp.209-219
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• 1981

To evaluate long-term metabolic response of free-living Korean subjects consuming local sources adequately or slightly below habitual intake. Subjects, six male medical students aged 23-25 years were free-living, but consumed diets in the metabolic unit. They were healthy as determined from medical laborarory tests. They belong to the Korean middle-class. Temperature of outdoor during study were ranged between -2 to $26^{\circ}C$, whereas the indoor were $18-22^{\circ}C$. Animal protein ranged between 25-30% of total calorie. The three meals and a vitamin supplement to meet recommendation were given daily. Three 50day periods following the design were used to test the protein-energy adequacy of the diet. Urinary nitrogen excretion was measured daily. Fecal samples were pooled for the last 5 days of each week. Nitrogen balance was computed using 5mg N/Kg skin and miscellaneous losses. Body weight was measured daily. The study was covered on 126 metabolic observations weekly. Body weight changes were relatively stable with the energy intake of 37-44Kca1/kg, and N-balances were also relatively stable, but it was influenced by physical and or mental stress somehow. It could be assumed that the mean protein and energy requirement were $190{\pm}10mg$ N/Kg with $41{\pm}2$ Kcal/kg, and the mean digestibility of protein was 81% on these subjects with the experimental conditions. The protein requirement, however, could be cut down somewhat with some limited increaing of energy intake under parameters of N-balance and maintaining body weight. It was also observed a tendency of the requirement were getting smaller with the increase of body size.

• Journal of the East Asian Society of Dietary Life
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• v.4 no.3
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• pp.21-30
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• 1994

The relationship between bone mineral density and the environmental factors were investigated from the view point of preventing osteoporosis in Korean pubescent girls. The effects of calcium, nutrient intake, physical activity on total bone mineral density, lumbar spine and femoral bone mineral density and total bone mineral content were evaluated 33 healthy pubescent girls aged 14∼16y. A convenient method was used to assess nutritional and energy intake and calcium index was used together. Calcium intake in childhood was estimated by asking whether subjects usually drank milk as children. Eating habits data and history of menstruation were obtained by questionnaire and interview. Average energy expenditure was calculated. Bone mineral density and content were measured by dual energy x-ray absorptiometry using a Lunar DPX＋Scanner (Lunar, Madison, WI). The lumbar spine(L2∼L4) and three sites in the proximal femur (femoral neck, trochanteric region, and Ward's triangle)were measured. Height and weight were measured, and the body mass index(BMI) was derived from the formula : BMI=kg/㎡ Statistical analysis was performed by simple correlation using the SAS package. The mean calcium intake (736mg) was below the RDA of 800mg/d. Twelve percent of the total subjects did not drink milk at all because they did not like the taste. Skipping meals, low calcium intake and low energy intake were significantly correlated with the low BMD. Also the data indicate that girls who reported drinking milk with every meal during childhood had significantly higher bone densities than girls who reported drinking milk less frequently. The results suggest that milk consumption in childhood appears to be needed not only for growth and development, but possibly also to assure an optimal peak of bone mass and thus greater latitude for the maintenance or skeletal integrity in the face of bone losses. There was a highly significant correlation between the total BMD and overall level of physical activity. Body weight was a better predictor of total BMD than was and other factor. Simple mechanical loading may explain why body weight, but total BMC was positively relatd to height. Conclusively, increasing calcium intake and physical activity in the pubescent girls could influence BMD.

• International Journal of Precision Engineering and Manufacturing
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• v.9 no.1
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• pp.39-46
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• 2008

The end plates of fuel cell assemblies are used to fasten the inner stacks, reduce the contact pressure, and provide a seal between Membrane-Electrode Assemblies (MEAs). They therefore require sufficient mechanical strength to withstand the tightening pressure, light weight to obtain high energy densities, and stable chemical/electrochemical properties, as well as provide electrical insulation. The design criteria for end plates can be divided into three parts: the material, connecting method, and shape. In the past, end plates were made from metals such as aluminum, titanium, and stainless steel alloys, but due to corrosion problems, thermal losses, and their excessive weight, alternative materials such as plastics have been considered. Composite materials consisting of combinations of two or more materials have also been proposed for end plates to enhance their mechanical strength. Tie-rods have been traditionally used to connect end plates, but since the number of connecting parts has increased, resulting in assembly difficulties, new types of connectors have been contemplated. Ideas such as adding reinforcement or flat plates, or using bands or boxes to replace tie-rods have been proposed. Typical end plates are rectangular or cylindrical solid plates. To minimize the weight and provide a uniform pressure distribution, new concepts such as ribbed-, bomb-, or bow-shaped plates have been considered. Even though end plates were not an issue in fuel cell system designs in the past, they now provide a great challenge for designers. Changes in the materials, connecting methods, and shapes of an end plate allow us to achieve lighter, stronger end plates, resulting in more efficient fuel cell systems.

• Toxicological Research
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• v.29 no.1
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• pp.27-34
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• 2013

This study was conducted to investigate the potential embryo-fetal toxicity and toxicokinetics of the antimalarial agent artesunate (ARTS) in Sprague-Dawley rats. Pregnant rats were administered ARTS daily from gestational day 6~15 via oral gavage, at test doses of 0, 2, 4, or 8 mg/kg (22 females per group). The fetuses were examined for external, visceral, and skeletal abnormalities on gestational day 20. With regard to the dams, there were no deaths, treatment-related clinical signs, changes in body weight, or food intake in any of the treatment groups. There were no treatment-related gross findings at necropsy in any treatment group. In the 8 mg/kg group, there was a decrease in gravid uterine weight and in the weight of female fetuses. There was also an increase in fetal deaths (primarily late resorptions) and an increase in post-implantation losses (37%) at 8 mg/kg. An increase in the incidence of visceral and skeletal variations at 4 and 8 mg/kg was observed. These defects included minor changes in the appearance of the kidney and thymus, as well as absent ribs or thoracic vertebrae. Toxicokinetics were assessed in a parallel study, using 4 mated females per group. Using liquid chromatography-mass spectrometry (LC-MS) analysis, the concentration of ARTS and its metabolite dihydroartemisinin (DHA) were quantified in plasma from rats on gestational days 5, 6, 10, and 15. Amniotic fluid was assayed for ARTS and DHA on gestational day 15. There was evidence of rapid conversion of ARTS to the metabolite DHA in maternal plasma, since ARTS could not be consistently detected in plasma at the three doses tested. ARTS and DHA were not detected in amniotic fluid at gestational day 15, indicating limited placental transfer of the two agents. The embryo-fetal no-observable-adverse-effect level (NOAEL) of the test item was considered to be 8 mg/kg/day for dams, and 2 mg/kg/day for embryo-fetal development.

• Korean Journal of Veterinary Research
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• v.36 no.1
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• pp.209-219
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• 1996

This study examined the effect of alcohol(AL) and/or paraquat(PQ) on serum TSH, thyroid hormones and enzyme activities, and the protective effect of selenium(SE) againse alcohol and/or paraquat-induced thyroid toxicity in guinea pigs. The experomental group consisted of control, 15% alcohol(AL), 4ppm sodium selentite(SE), 200ppm paraquat(PQ), AL+PQ, AL+SE, PQ+SE and AL+PQ+SE mixed in drinking water-fed guinea pigs for 4 weeks. The morphological changes of thyroid gland were studies on paraffin-embedded sections stained with H-E stain. Body weight losses, high serum concentration in TSH and cholesterol, and low values on triiodothyronine($T_3$), thyrozine($T_4$), free $T_4$ and alkaline phosophatase(ALP) were produced in the groups fed AL and/or PQ. We also noted that AL+PQ-fed group was marked increase in serum TSH. In AL or AL+PQ-fed groups when cpmpared to control group had increased the ratio of thyroid weight to body weight(ratio Twt/Bwt), whereas the ratio Twt/Bwt was decresed in SE or PQ-fed groups. However, the serum TSH, $T_3$,$T_4$ free $T_4$ and cholesterol values, and the ratio Twt/Bwt were reversed in groups given the combination of SE, compared with AL and/or Pq-fed groups, also ALP values were reversed in groups given the combination of SE, compared with AL or AL+PQ-fed groups. In microscope, morphological changes showed a remarkable between the AL or PQ-fed group and controls. In AL+PQ+SE-fed guinca pig, follicular colloid is high density in thyroid follicle and increased in connective tissue around the thyroid cells, and thyroidal epithelia were composed of cuboidal or columnar epithelium. The indicated that the morphological changes of thyroid were direct action in the thyroid cell. The results of this study confirmed that the toxic effect of AL or PQ on thyroid occur independently of changes in liver function, and that SE confers marked protection against AL or PQ-induced thyroid toxicity.

• Korean Journal of Community Nutrition
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• v.11 no.6
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• pp.785-792
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• 2006

The purpose of this study was to investigate the nutritional status before and after gastrectomy of gastric cancer patients in Jeonbuk Province. The subjects were 136 patients with gastrectomy of gastric cancer. We assessed the nutritional status before and after an operation by general characteristics (age, clinicopathological stage, type of operation, method of reconstruction), anthropometric characteristics (height, weight, skeletal muscle mass, body fat mass, body mass index (BMI), percent body fat, arm muscle circumference AMC, arm circumference AC) and biochemical characteristics (hemoglobin Hb, hematocrit Hct, mein corpuscular volume MCV, mean corpuscular hemoglobin MCH, total lymphocyte count TLC, serum albumin, serum transferrin). Mean ages were 60.0 yrs in males and 58.8 yrs in females. Age, clinicopathological stage, types of operation and reconstruction methods were not significantly different between males and females. Weight, skeletal muscle mass, body fat mass, BMI, percent body fat, AMC and AC significantly deteriorated by gastrectomy. There were severe weight losses in males and females after gastrectomy. Hemoglobin, Hct, MCV, MCH, TLC, albumin and transferrin significantly deteriorated by gastrectomy. After gastrectomy, subjects who were assessed as malnounrished in Hb and Hct were increased in male and those who were assessed as malnounrished in Hb were increased in females. These results suggest that a nutrition intervention, specially for energy, protein and iron, is necessary to improve the nutritional status of gastric cancer patients with gastrectomy.

• Structural Engineering and Mechanics
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• v.70 no.2
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• pp.169-178
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• 2019

The replacement of damaged components is an important task for long-span bridges. Conventional strategy for component replacement is to close the bridge to traffic, so that the influence of the surrounding environment is reduced to a minimum extent. However, complete traffic interruption would bring substantial economic losses and negative social influence nowadays. This paper investigates traffic control technologies without interruption for component replacement of long-span bridges. A numerical procedure of traffic control technologies is proposed incorporating traffic microsimulation and site-specific data, which is then implemented through a case study of cable replacement of a long-span cable-stayed bridge. Results indicate traffic load effects on the bridge are lower than the design values under current low daily traffic volume, and therefore cable replacement could be conducted without traffic control. However, considering a possible medium or high level of daily traffic volume, traffic load effects of girder bending moment and cable force nearest to the replaced cable become larger than the design level. This indicates a potential risk of failure, and traffic control should be implemented. Parametric studies show that speed control does not decrease but increase the load effects, and flow control using lane closure is not effectual. However, weight control and gap control are very effective to mitigate traffic load effects, and it is recommended to employ a weight control with gross vehicle weight no more than 65 t or/and a gap control with minimum vehicle gap no less than 40 m for the cable replacement of the case bridge.

• Journal of The Korean Society of Agricultural Engineers
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• v.63 no.3
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• pp.13-26
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• 2021

Recent drought events in the South Korea and the magnitude of drought losses indicate the continuing vulnerability of the agricultural drought. Various studies have been performed on drought hazard assessment at the regional scales, but until recently, drought management has been response oriented with little attention to mitigation and preparedness. A vulnerability assessment is introduced in order to preemptively respond to agricultural drought and to predict the occurrence of drought. This paper presents a method for spatial, Geographic Information Systems-based assessment of agricultural drought vulnerability in South Korea. It was hypothesized that the key 14 items that define agricultural drought vulnerability were meteorological, agricultural reservoir, social, and adaptability factors. Also, this study is to analyze agricultural drought vulnerability by comparing vulnerability assessment according to weighting method. The weight of the evaluation elements is expressed through the Analytic Hierarchy Process (AHP), which includes subjective elements such as surveys, and the Entropy method using attribute information of the evaluation items. The agricultural drought vulnerability map was created through development of a numerical weighting scheme to evaluate the drought potential of the classes within each factor. This vulnerability assessment is calculated the vulnerability index based on the weight, and analyze the vulnerable map from 2015 to 2019. The identification of agricultural drought vulnerability is an essential step in addressing the issue of drought vulnerability in the South Korea and can lead to mitigation-oriented drought management and supports government policymaking.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.11
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• pp.1632-1638
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• 2016

A study was conducted to compare the endogenous basal losses of phosphorus (EBLP) in pigs fed diets containing gelatin (GEL) or spray-dried porcine plasma (SDPP) as protein sources and to determine the standardized total tract digestibility (STTD) of phosphorus (P) in SDPP. The trial was carried out at the Federal University of Santa Maria, Brazil. Twelve castrated pigs with an initial body weight of 55 kg were individually allotted in metabolic crates during two 12-day periods, each with 7 days of adaptation and 5 days of total fecal collection. The beginning and the end of the collecting periods were determined according to the marker-to-marker approach, using ferric oxide as an indigestible marker. Pigs were submitted to four semi-purified diets, one being a P-free diet with 30% of GEL as the protein source and three were diets with 10%, 20%, and 30% inclusion of SDPP respectively. Data were subjected to analysis of variance and the model included the effects of period, animal and treatments; the results of the three diets with increased levels of SDPP were subjected to linear regression analysis. The intercept of the relation of between ingested P and absorbed P represented the EBLP, while the slope indicated the STTD of P in SDPP. The EBLP means obtained by P-free diet and regression method were compared with the Student t test. The EBLP were 128.95 mg/kg dry matter intake (DMI) and 153.63 mg/kg DMI (standard error = 77.0; p<0.06) using the P-free diet with GEL as the protein source and the regression method, obtained with diets containing increased levels of SDPP, respectively. The apparent digestibility of P was 87.9%, 94.2%, and 92.9% for the treatments containing 10%, 20%, and 30% inclusion of SDPP, respectively. The estimated STTD of P obtained with the linear regression was 97.4%. When the EBLP estimated by the P-free diet was used to corrected the apparent digestibility of P in diets containing SDPP, the STTD of P in SDPP was 96.9%, 98.8%, and 95.9% for 10%, 20%, and 30% SDPP, respectively. Therefore, it can be concluded that SDPP can replace GEL to estimate the endogenous losses of P. In addition, the STTD of P in SDPP estimated with the P-free diet was 97.2% and it was 97.4% by the regression method, utilizing SDPP.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.5
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• pp.62-71
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• 2003

This study was carried out to develop the bio-chemical pulping method to enhance the energy saving and decrease the capital cost through the soda pulping under atmospheric pressure ($100^{\circ}C$). Nonwood substrates, rice straw, were pretreated by white-rot fungi, Pleurotus cornucopiae. Several basic pieces of data that can be applied in soda pulping were acquired. The results of this study were as follows. Under the conditions without any nutrients or with glucose, N and glucose + N, the weight losses of rice straws inoculated by Pleurotus cornucopiae were 12.1∼32.6 %, 12.0∼26.3 %, 13.0∼25.4 % and 15.3∼24.7 % for 5, 10, 15, 20, 25 and 30 days incubation periods respectively. The more the fungal incubation was extended, the more the weight losses were gained. The yield of untreated rice straw was 54.8 % after pulping. When any nutrients was not added or glucose, N and glucose ＋ N were added for the pretreatment, the total yields were ranged to 57.3∼42.9 %, 51.0∼43.3 %, 51.7∼43.9 % and 52.1∼46.1 % for 5 different incubation periods respectively. The yields were gradually decreased based on the extending of the incubation periods. The physical properties of the rice straw soda pulp without fungal treatment, the density, breaking length, burst index, tear index and folding endurance were 0.24g/㎤, 2.32 Km, 0.91 kPaㆍ$m^2$/g, 46.7 mNㆍ$m^2$/g and 21 times, respectively. In the case of pretreatment without any nutrients or with glucose, N and glucose + N as nutrients, the density was 0.24g/㎤, the breaking length was 3.30∼6.46 Km, the burst index was 1.36∼3.01 kPaㆍ$m^2$/g, the tear index was 33.0∼57.0 mNㆍ$m^2$/g and the folding endurance was 14∼381 times at most incubating periods, when pulping was done. The physical properties were increased as the incubation duration was extended. Especially, when N and glucose ＋ N were added, the physical properties showed superior results during each incubation period.