• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.1
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• pp.123-132
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• 2021

Radiological impact analyses were carried out for a near-surface radioactive waste repository at Gyeongju in South Korea. The RESRAD-ONSITE code was applied for the estimation of maximum exposure doses by considering various exposure pathways based on a land area of 2,500 ㎡ with a 0.15 m thick contamination zone. Typical influencing input parameters such as shield depth, shield materials' density, and shield erosion rate were examined for a sensitivity analysis. Then both residential farmer and industrial worker scenarios were used for the estimation of maximum exposure doses depending on exposure duration. The radiation dose evaluation results showed that 60Co, 137Cs, and 63Ni were major contributors to the total exposure dose compared with other radionuclides. Furthermore, the total exposure dose from ingestion (plant, meat, and milk) of the contaminated plants was more significant than those assessed for inhalation, with maximum values of 5.5×10-4 mSv·yr-1 for the plant ingestion. Thus the results of this study can be applied for determining near-surface radioactive waste repository conditions and providing quantitative analysis methods using RESRAD-ONSITE code for the safety assessment of disposing radioactive materials including decommissioning wastes to protect human health and the environment.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.9
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• pp.1341-1350
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• 2009

Dietary lipids are rapidly hydrolysed and biohydrogenated in the rumen resulting in meat and milk characterised by a high content of saturated fatty acids and low polyunsaturated fatty acids (PUFA), which contributes to increases in the risk of diseases including cardiovascular disease and cancer. There has been considerable interest in altering the fatty acid composition of ruminant products with the overall aim of improving the long-term health of consumers. Metabolism of dietary lipids in the rumen (lipolysis and biohydrogenation) is a major critical control point in determining the fatty acid composition of ruminant lipids. Our understanding of the pathways involved and metabolically important intermediates has advanced considerably in recent years. Advances in molecular microbial technology based on 16S rRNA genes have helped to further advance our knowledge of the key organisms responsible for ruminal lipid transformation. Attention has focused on ruminal biohydrogenation of lipids in forages, plant oils and oilseeds, fish oil, marine algae and fat supplements as important dietary strategies which impact on fatty acid composition of ruminant lipids. Forages, such as grass and legumes, are rich in omega-3 PUFA and are a useful natural strategy in improving nutritional value of ruminant products. Specifically this review targets two key areas in relation to forages: i) what is the fate of the lipid-rich plant chloroplast in the rumen and ii) the role of the enzyme polyphenol oxidase in red clover as a natural plant-based protection mechanism of dietary lipids in the rumen. The review also addresses major pathways and micro-organisms involved in lipolysis and biohydrogenation.

• Journal of Animal Science and Technology
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• v.44 no.2
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• pp.251-260
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• 2002

The corn (Zea mays L) planting date in a double-cropping system is delayed until mid-May due to delayed rye harvest on May. This experiment was conducted to determine the optimum harvesting time for high yield and the best quality of silage corn at late planting date after harvesting winter rye. Corns were planted on 21 May and harvested at eight different maturity stage at Seoul National University Experimental Livestock Farm, Suwon in 1997. Maturities were B (blister; 16 days after silking), M (milk; 20 days), LM (late milk; 24 days), SD (soft dough; 28 days), ED (early dent; 33 days), FD (full dent; 38 days), LD (late dent; 44 days) and PM (physiological maturity; 53 days) stages. The percentage of whole plant dry matter (DM) showed optimum range for silage making (29.0 to 38.5%) when corn plant was harvested at between ED and LD stages. Maximum whole plant DM (14,831 kg/ha) and total digestible nutrients (TDN) yields (10,675 kg/ha) reached at full dent stage. The percentage of whole plant acid detergent fiber (ADF) was decreased from 35.4 to 22.1%, and that of neutral detergent fiber (NDF) was also decreased from 63.8 to 46.0% as harvest stage progressed. These changes in chemical compositions were associated with changes in plant part composition. A progressive increase in total ear, and the decrease in stover portion in the plant were observed with advance in harvest stage. Calculated on net energy for lactation (NEL) and TDN values based on ADF percentage of stover plant decreased by ED stage and then increased by PM stage. But NEL and TDN values of ear and whole plant increased as harvest stage progressed. While in vitro dry matter digestibility of stover was decreased from 61.1 to 49.7%, whole plant was increased from 58.3 to 65.7% as maturity advanced (P$<$0.05). The results of this study indicate that corn can be harvested for silage at full (1/2 milkline) and late dent (2/3 milkline) stages for maximum yield and optimum quality at late planting. And days after silking at late planting was 38 and 44 days.

• The Korean Journal of Food And Nutrition
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• v.27 no.3
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• pp.484-494
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• 2014

The purpose of this study was to evaluate dietary intake according to the risk of coronary heart disease (less than 10% = low-risk group; 10~20% = middle-risk group) based on Framingham risk score (FRS), on 122 male adult subjects. The body weight and body mass index were not significantly different between the groups, while height of the low-risk group was shown to be significantly high compared to that of the middle-risk group. The daily energy intake was shown to be significantly high in the low-risk group with 1,910.88 kcal, compared to 1,606.63 kcal of the middle-risk group. As a result of analyzing nutrient intake per 1,000 kcal of energy, while the low-risk group had significantly high intake of animal protein, fat, and animal fat compared to the middle-risk group, the intake of plant protein, carbohydrate, and plant iron was found to be significantly low. The daily food intake was shown to be significantly high in the low-risk group (1,445.16 g), compared to the middle-risk group (1,075.12 g). The low-risk group was found to have significantly high intake of sugars, eggs, and beverages compared to the middle-risk group, while mushrooms intake was significantly high in the middle-risk group. Dietary variety score (DVS) was significantly high in the low-risk group with 26.42, compared to 22.66 of the middle-risk group. Dietary diversity score (DDS) was indicated to be significantly high in the low-risk group with 3.70, compared to 3.27 of the middle-risk group. The low-risk group was indicated to have significantly high score in DDS of dairy products and fruit group, compared to the middle-risk group. In the correlation between diversity index of food intake (DVS and DDS) and FRS, DDS was shown to have significantly negatively correlation with FRS after adjusting for confounding factors. To sum up these results, the adult males with low-risk of coronary heart disease had more various consumptions of fruits and milk, compared to the subjects with the middle-risk. The proportion of consuming major food groups such as cereals, meat group, milk, fruits, and vegetables more than a fixed quantity was indicated to be high. Accordingly, dietary habit for intake of various food seems to be necessary, to prevent coronary heart disease.

• Korean Journal of Community Nutrition
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• v.6 no.4
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• pp.668-677
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• 2001

This study conducted to assess the effectiveness of nutrition education program for elderly females with various diseases. Forty subjects(hypertension ; 20, diabetes ; 12, hyperlipidemia ; 8) out of 56 completed the 7 weeks nutrition education program. The nutrition education program was based for healthy food habits and dietary guidelines for each specific disease. It also included practicing individualized menu planning and exercising program. Energy, calcium, iron, vitamin A and ash intakes significantly increased in the hypertension group. total sodium intake did not decrease, however sodium intake per kcal decreased significantly(p〈0.05). Elderly with diabetes did not show any changes in dietary intakes. Dietary protein, plant fat, ash, and sodium intakes were significantly elevated(p〈0.05), but cholesterol intakes significantly decreased(p〈0.05) in the hyperlipidemic group. Elderly with hypertension agreed strongly with changes of food habits such as increasing milk intake, and decreasing Kimchi, soup, pickles and salty food, and table salt intakes after nutrition education. Diabetic elderly showed significantly improved food habit scores in decreasing white rice intake, sugar intake and increasing sea-weed consumption, vegetable consumption and exercise. Hyperlipidemic elderly did not show much improvement in food habit scores except in biochemical indices. However, mean serum glucose and atherogenic index decreased in the diabetic and hyperlipidemic groups after education, respectively.

• Applied Biological Chemistry
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• v.27
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• pp.56-67
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• 1984

As in many other country, the use of organic matter in Korea has long history. Farmers understand the value of organic matter as the source of plant nutrient and soil improving agent in general. Since 50 years ago, the sources of organic matter in paddy soils were compost, rice and barly straw, green manure, animal waste, fish and beancake, etc.. Application of green manures such as vetch and chinese milk vetch showed no significant effect on the yield of brown rice in paddy soil. On the other hand, the effects of compost and rice straw showed more significant on the yield of brown rice in paddy soil. Application of rice straw in rice cultivation is commonly made at different times between harvest, early spring and several weeks before transplanting. Considering the suitable paddy soil for application of rice straw under well to moderately well drained soil, the yield was pronounced more than poorly drained soil. Based on laboratory and field experimants, application of rice straw promoted the decrease of oxidation-reduction potential in well to moderately well drained soil. This results to be enhanced the release of some mineral nutrients,. such as potassium, calcium, silicon, and increase of availability of soil phosphorus. In the field experiments, results obtained from nitrogen fraction on the immobilization-mineralization of the tracer nitrogen applied in paddy soil,the amount and index of organic nitrogen incoporated in soil was more pronounced in rice straw application than control. Rice straw and its transformation products incoporated in the soil, provided the inflow of energy necessary to maintain heterotrophic microbes activities. Rice straw and its transformation products, especially soluble carbohydrate, enhanced the population of free-living heterotrophic $N_2$ - fixing microbes. Moreover, rice straw and its transformation products in paddy soil, enhanced the activities of soil enzymes such as dehydrogenase and urease.

• Journal of Korean Society on Water Environment
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• v.36 no.6
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• pp.500-507
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• 2020

This study examined the wastewater at a livestock farm, and found that the dairy wastewater from the milking parlor had a lower concentration than the piggery wastewater, and that it was produced at a rate under 1.3 ㎥/day in a single farmhouse. The amount of dairy wastewater was determined based on the performance of the milking machine, the maintenance method of the milking parlor, and the amount of milk production allocated for each farmhouse, not by the area. The results confirmed that both dairy wastewater treatment processes, specifically those using Hanged Bio-Compactor (HBC) and Sequencing Batch Reactor (SBR), can fully satisfy the water quality standards of discharge. The dairy wastewater has a lower amount and concentration than piggery wastewater, meaning it is less valuable as liquid fertilizer, but it can be easily degraded using the conventional activated sludge process in a public sewage treatment plant. Therefore, discharging the dairy wastewater after individual treatment was expected to be a more reasonable method than consigning it to the centralized wastewater treatment plant. The effluent after the SBR process showed a lower degree of color than the HBC effluent, which was attributed to biological adsorption. In the case of the milking parlor in the livestock farm, the concentrations of the effluents obtained after HBC and SBR treatments both satisfied water quality standards for the discharge of public livestock wastewater treatment plants at 99% confidence intervals, and the concentrations of total nitrogen and phosphorous in untreated wastewater were even lower than the water quality standards of discharge. Therefore, we need to discuss strengthening the water quality standards to reduce environmental pollution.

• Nutrition Research and Practice
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• v.17 no.1
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• pp.48-61
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• 2023

BACKGROUND/OBJECTIVES: Magnesium is an essential nutrient for human health. However, inadequate intake is commonly reported worldwide. Along with reduced consumption of vegetables and fruits and increased consumption of refined or processed foods, inadequate magnesium intake is increasingly reported as a serious problem. This study aimed to assess magnesium intake, its dietary sources, and the adequacy of magnesium intake in Korean populations. SUBJECTS/METHODS: Data was obtained from the Korea National Health and Nutrition Examination Survey 2016-2019 and included individuals aged ≥1 yr who had participated in a nutrition survey (n=28,418). Dietary intake was assessed by 24-h recall, and dietary magnesium intake was estimated using a newly established magnesium database. Diet adequacy was evaluated by comparing dietary intake with the estimated average requirement (EAR) suggested in the Korean Dietary Reference Intakes 2020. RESULTS: The mean dietary magnesium intake of Koreans aged ≥1 yr was 300.4 mg/d, which was equivalent to 119.8% of the EAR. The prevalence of individuals whose magnesium intake met the EAR was 56.8%. Inadequate intake was observed more in females, adolescents and young adults aged 12-29 yrs, elders aged ≥65 yrs, and individuals with low income. About four-fifths of the daily magnesium came from plant-based foods, and the major food groups contributing to magnesium intake were grains (28.3%), vegetables (17.6%), and meats (8.4%). The top 5 individual foods that contributed to magnesium intake were rice, Baechu (Korean cabbage) kimchi, tofu, pork, and milk. However, the contribution of plant foods and individual contributing food items differed slightly by sex and age groups. CONCLUSIONS: This study found that the mean dietary magnesium intake among Koreans was above the recommended intake, whereas nearly one in 2 Koreans had inadequate magnesium intake. To better understand the status of magnesium intake, further research is required, which includes the intake of dietary supplements.

• Korean Journal of Environmental Agriculture
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• v.42 no.3
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• pp.220-230
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• 2023

Imidacloprid is a neonicotinoid insecticide widely used for insect control in a variety of crops. The evaluation of imidacloprid total residues in animal feeds derived from crop by-products is required to ensure the safety of livestock products. We performed simultaneous LC/MS/MS analyses of imidacloprid and its metabolites in five different livestock products including beef, pork, chicken, milk and egg from domestic markets. The methods for sample preparation and instrumental analysis were established by modifying QuEChERS method to meet the Codex guidelines. The methods generated 0.0035 mg/kg of the limit of determination (LOD), 0.01 mg/kg of the limit of quantitation (LOQ) and standard calibration linearity with >0.983 of the coefficients of determination (R²). The methods exhibited the recovery values of imidacloprid and its metabolites ranging from 65.66 to 119.27% without any interference between matrices. Imidacloprid total residues in the livestock products were found as values lower than the LOQ and maximum residue limits (MRLs). This study suggests that the methods are successfully applicable for the safety evaluation of imidacloprid total residues in livestock products from domestic markets.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.137-146
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• 2018

The purpose of this study was to derive and analyze the hub facilities that occupy major positions in the vehicle movement networks of livestock facilities. For this purpose, this study used the KAHIS data provided by Animal and Plant Quarantine Agency. The hub facilities were derived from the degree centrality & betweenness centrality. The analysis results are summarized as follows. First, in a livestock facility's vehicle movement network, there are a small number of hub facilities with very high centrality indicator values compared to other facilities. Second, the hub facilities based on the degree centrality are the feed factory, the milk collecting center, slaughterhouse, slaughterhouse for chicken, and livestock markets. Third, the hub facilities based on the betweenness centrality are the livestock markets, the feed factory, and slaughterhouse. Fourth, hub facilities based on the degree centrality are concentrated in a particular area, but the hub facilities based on betweenness centrality are distributed relatively evenly.