• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.3
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• pp.190-198
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• 2006

Radiation use efficiency (RUE), the amount of biomass produced per unit intercepted photosynthetically active radiation (PAR), constitutes a main part of crop growth simulation models. The objective of the present study was to evaluate the variation of RUE of rice plants under various nitrogen nutritive conditions. from 1998 to 2000, shoot dry weight (DW), intercepted PAR of rice canopies, and nitrogen nutritive status were measured in various nitrogen fertilization regimes using japonica and Tongil-type varieties. These data were used for estimating the average RUEs before heading and the relationship between RUE and the nitrogen nutritive status. The canopy extinction coefficient (K) increased with the growth of rice until maximum tillering stage and maintained constant at about 0.4 from maximum tillering to heading stage, rapidly increasing again after heading stage. The DW growth revealed significant linear correlation with the cumulative PAR interception of the canopy, enabling the estimation of the average RUE before heading with the slopes of the regression lines. Average RUE tended to increase with the increased level of nitrogen fertilization. RUE increased approaching maximum as the nitrogen nutrition index (NNI) calculated by the ratio of actual shoot N concentration to the critical N concentration for the maximum growth at any growth stage and the specific leaf nitrogen $(SLN;\;g/m^2\;leaf\;area)$ increased. This relationship between RUE (g/MJ of PAR) and N nutritive status was expressed well by the following exponential functions: $$RUE=3.13\{1-exp(-4.33NNNI+1.26)\}$$ $$RUE=3.17\{1-exp(-1.33SLN+0.04)\}$$ The above equations explained, respectively, about 80% and 75% of the average RUE variation due to varying nitrogen nutritive status of rice plants. However, these equations would have some limitations if incorporated as a component model to simulate the rice growth as they are based on relationships averaged over the entire growth period before heading.

• Journal of Animal Science and Technology
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• v.53 no.5
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• pp.481-487
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• 2011

Rearing density is a major factor in welfare production and health of broiler chicks. An experiment was conducted to investigate the effect of rearing density on the behavioral characteristics of Korean native chicks. In the study, 20, 30, and 40 chicks per pen (3.17 $m^2$) were used in each treatment and randomly allotted to 6.3 bird/$m^2$, 9.5 bird/$m^2$, and 12.6 bird/$m^2$ density, respectively. The broilers' behavior was recorded for 12 hours continuously during 1 to 8 weeks of age. The time budgets (standing, sitting, and walking) and frequencies of certain behaviors (drinking, feeding, preening, scratching, dust bathing, flapping, aggressive pecking, and pecking) in the broilers were checked during the day. The behavioral characteristics in the early period (1 to 4 weeks) were compared to the later period (5 to 8 weeks) to know the changes in each behavior as the chicks matured. It was observed that 40 chicks per pen showed significant decrease in feed intake and body weight. Corticosterone hormone was higher in the order of 12.6 bird/$m^2$ > 9.5 bird/$m^2$ > 6.3 bird/$m^2$ (p<0.05). The behaviors of standing and sitting were the highest in groups of 30 and 40 respectively. The walking behavior was gradually decreased as rearing density increased. The frequencies of the other behaviors also decreased in a high density treatment; especially for feeding, drinking, preening, and pecking. These tendencies widened the gaps of behaviors as time passed. It was concluded that a group of 20 chicks (6.3 bird/$m^2$) was the proper rearing density among these three treatments. Broilers in the lower rearing density showed more activity than that with higher density and therefore this environment may lead to better welfare condition.

• Applied Biological Chemistry
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• v.37 no.2
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• pp.65-71
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• 1994

Chungkook-Jang was produced by fermenting Bacillus licheniformis CN-115. The changes of chemical composition, enzyme activity, and amino acids during the fermentation were investigated. The proximate composition was shown irregular fluctuation phenomenon during the fermentation, but only the moisture tended some reducing during the fermentation just after steaming. The content of amino nitrogen was increased radically after the 36 hours of fermentation and became the highest level at 18.072 mg/g at the 60 hours of it. In accordance with the fermentation of Chungkook-Jang, pH got to the 8.39 at 60 hours with increasing, protease activity was increased according to the fermentation and acid and neutral protease activity was reduced after being reached at the highest activity at 48 hours. The most suitable pH was 6.5 and temperature was $35^{\circ}C$ for dissolution-activated of protein in the process of fermentation of Chungkook-Jang. The content of water soluble protein and the content of salt soluble protein were increased at continuously according to the fermentation time of Chungkook-Jang the largest quantity. The molecular weight of water soluble protein of Chungkook-Jang fermented for 48 hours was about 19,000. The amino acids of water soluble protein just after steaming were totally 16 kinds and proline was amino acid and them was in series by glutamic acid and serine in that ordered. The amino acids salt soluble protein, just after steaming were totally 16 kinds and was the largest quantity phenylalanine, glutamic acid and aspartic acid and aspartic acid in that order.

• Journal of Animal Environmental Science
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• v.17 no.2
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• pp.115-122
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• 2011

This study was conducted to investigate the changes in growth performance, blood hormone levels and immunity of weaning pigs by the installation of warm curtain for keeping warmth in pigpen. A total of sixty-four piglets was weaned at 21 d of age with an average body weight of 5.8 kg. Each thirty-two piglets were allocated into the pens with (TRT) or without warm curtain (CONT). Daily gain and feed intake were increased by 17% and 9% in TRT from 2nd week to 4th week compared with CONT, respectively. The occurrence of diarrhea was decreased by 62% in TRT from initial to 2nd week compared with CONT. There were no significant differences in blood hormone levels and immunity of weaning pigs between treatments. In conclusion, the installation of warm curtain, which supported high temperature in pigpen, was considered to be effective in improving growth performance and reducing diarrhea occurrence of weaning pigs.

• Journal of Nutrition and Health
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• v.41 no.2
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• pp.147-155
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• 2008

Medical nutrition therapy (MNT) is considered a keystone of medical treatment of chronic diseases. However, only few studies have evaluated medical and economical outcome of MNT. The study was performed on the patient with type 2 diabetes mellitus to evaluate the effect of clinical and cost-effective outcomes of MNT. Subjects from two general hospitals were randomly assigned to two different groups; One receiving basic nutritional education (BE) (n = 35), and the other receiving intensive nutritional education (IE) (n = 32) for a 6-month clinical trial. The group which received BE had a single visit with a dietitian, while the other group which received IE had an initial visit with a dietitian addition to two visits during the first 4 weeks of the study periods. Anthropometric parameters, blood components, and dietary intake were measures at the beginning of study period and after 6 month. Cost-effective analysis included direct labor costs, educational materials and medication cost difference during 6 months. After 6 month, subjects from IE group showed significant reduction of body weight (p <0.05) and systolic blood pressure (p <0.05), whereas BE group did not show any significant changes. Result from biochemical indices showed glycated hemoglobin concentration was significantly reduced by 0.7% (p <0.05) only in the IE group. The ratio of energy intake to prescribed energy intake decreased significantly in both groups (p <0.05). Mean time taken for a dietitian to educate the subject was 67.9 ${\pm}$ 9.3 min/person for BE group, while 96.4 ${\pm}$ 12.2 min/person for IE group. Mean number of educational materials was 1.9 ${\pm}$ 0.7/person for BE group and 2.5 ${\pm}$ 0.7/person for IE group. Change in glycated hemoglobin level along the 6 month period of study can be achieved with an investment of \88,510/% by implementing BE and \53,691/% by implementing IE. Considering the net cost-effect of blood glucose control and HbA Ic, IE which provides MNT by dietitian had a cost efficiency advantage than that of BE. According to this study, MNT provided by dietitian had a significant improvements in medical and clinical outcomes compared to that of BE intervention. Therefore, MNT protocol should be performed by systemic intensive nutrition care by dietitian in clinical setting to achieve good therapeutic results of DM with lower cost.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.203-213
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• 2017

This study investigated the changes in yields, antioxidant compounds, and antioxidant activities among 11 adzuki bean cultivars cultivated in a paddy field with somewhat poorly drained soil. The adzuki bean cultivars were cultivated in the paddy field from 2015 to 2016 in Milyang, Gyeongsangnam, Korea. Average soil moisture content was 16.5% in 2015 and 31.0% in 2016 at the experimental site during adzuki bean cultivation. As the soil moisture content increased, most of the adzuki bean cultivars showed deceases in stem height, first setting pod node, number of pods, 100 seed weight, and yield. Chungju-pat produced the greatest yields among the 11 cultivars in 2015 and 2016, whereas Hongeon had the smallest yields. Adzuki bean yields after paddy field cultivation was lower for all cultivars than for adzuki bean yields from the same cultivars after upland field cultivation. Chungju-pat and Chilbo-pat showed the smallest decreases in yields after paddy field cultivation, whereas Hongeon and Kumsil showed the greatest yield reductions. There were no significant differences in proximate composition. Some mineral components ($P_2O_5$, Ca, and Mg) were statistically different across cultivars. Chungju-pat had the highest Ca and Mg contents, but antioxidant components (polyphenol and flavonoids) and antioxidant activities (ABTS and DPPH) were highest in Saegil and lowest in Jungbu-pat. PCA and clustering analyses, based on the growth, yield, and antioxidant component measurements, performed to identify which variables contributed the most to separating adzuki bean cultivars or to grouping cultivars with similar characteristics. These analyses showed that the antioxidant components and antioxidant activities had the most influence on grouping cultivars together. Among the 11 cultivars, Saegil was statistically different from the other cultivars, but the other 10 cultivars were not significantly different under paddy field cultivation. Soil moisture content affected adzuki bean yield and antioxidant component contents. An increase in soil moisture led to a decrease in yield, but an increase in antioxidant components. These results provide information that will improve the selection of an appropriate adzuki bean cultivar for use in paddy fields.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.2
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• pp.124-133
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• 2017

This experiment was conducted to evaluate the effects of high temperature on the stem, leaf and grain of barley during the ripening period and to provide information for the development of high-temperature cultivation techniques and adaptive varieties. We used an artificial climate control facility, to provide a temperature $3^{\circ}C$ higher than the normal average temperature during the ripening stage. Although the maximum rate of starch synthesis was increased at high temperature by approximately 11%, the starch content was decreased, because the period of starch synthesis ended 4 days earlier. As in the case of starch synthesis, the expression of genes related to starch synthesis was increased at the early ripening stage in the high temperature treatment, however, the duration of expression tended to decrease rapidly. Furthermore, the partitioning rate of assimilation products in the panicle increased to a greater extent in the high temperature treatment than in the control. In contrast, for the stem and leaf, the partitioning rate of assimilation products decreased more rapidly in the high temperature treatment than in the control. On the basis of these results, it can be considered that the translocation rate of assimilation products increased to a greater extent in the high temperature treatment than in the control at the early ripening stage. These results indicate that the decrease in grain weight at high temperature during the ripening stage is attributable to an increase in the speed of starch synthesis at high temperature, but the increase in ripening speed does not compensate for the shortening of the ripening period. Finally to develop varieties and cultivation techniques suited to high temperature, we need to focus on physiological characteristics related to the duration of starch synthesis.

• Journal of Food Hygiene and Safety
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• v.28 no.4
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• pp.360-366
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• 2013

The objective of this study is to investigate the effect of multivitamin on macrophage activity in Raw 264.7 cell and repeated oral dose toxicity in Sprague-Dawely rat of multivitamin. Raw 264.7 cells were treated with 50 and $100{\mu}g/mL$ multivitamin for 24 h. To measure the activity of macrophages, NO and TNF-${\alpha}$ assays were performed in Raw 264.7 cells. Treatment with 50 and $100{\mu}g/mL$ multivitamin for 24 h significantly increased production of NO and TNF-${\alpha}$ compared with control groups, indicating activation of macrophages. The female rats were treated with multivitamin of control group, low group (0.24 g/kg), medium group (1 g/kg) and high group (2 g/kg) intragastrically for 4 weeks, respectively. We examined the body weight, the feed intake, the clinical signs and serum biochemical analysis. We also observed the histopathological changes of liver, ovary, brain, adrenal gland, spleen, kidney, heart and lung in rats. No significant differences in body weights, feed intake, biochemical analysis and histopathological observations between control and multivitamin treatment group were found. In conclusion, multivitamin is physiologically safe and improve macrophage activity.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.3
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• pp.254-260
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• 2015

Changes of the growth, quality and physiological response of Chinese cabbage cv 'Chunkwang' in response to five different temperature treatments based on climate change scenario were investigated during the growing season. The treatments consisted of normal year temperature $-2.0^{\circ}C$ (I), normal year temperature (II; Control group), normal year temperature $+2.0^{\circ}C$ (III), normal year temperature $+4.0^{\circ}C$ (IV), and normal year temperature $+6.0^{\circ}C$ (V). Regarding fresh weight, number of leaves, and leaf area were high in group IV, and V before the head formation stage, but it has decreased during the later growth period. Rate of frangibleness sympton was the highest in group V as 85.7%, and it was decreased in group IV (64.3%), group III (28.6%), group II (14.3%), and group I (7.1%). Regarding photosynthetic rate, group III, IV, and V showed relatively high photosynthetic rate at 20 DAP but it was reduced dramatically during the later growth period. Transpiration and stomatal conductance showed the similar trend with the photosynthetic rate. When comparing the chlorophyll fluorescence reaction of each treatment group at 50 DAP, Fv/Fm in group I was highest as 8.04 among all treatment groups and the lowest in group IV as 7.15.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.659-667
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• 2000

Quality attributes of fresh-cut green onion(Allium fistulosum L.) as affected by rinsing and packaging were investigated in terms of flesh weight, color, viable cell counts, sensory properties during storage at $10^{\circ}C$. Fresh green onions were trimmed, cut, and rinsed with cold water(approximately $5^{\circ}C$) as well as chlorine solution(100 mg/L) and then packaged in low density polyethylene film pouches of $63\;{\mu}m$ thickness. Rinsing treatments with cold water or chlorine solution did not significantly influence changes in microbial populations but sensory characteristics, resulting in cut green onions of better visual quality as compared to the control without rinsing. Fresh-cut green onions were also rinsed with cold water and packaged in sealed bags of low density polyethylene films with different thickness(22, 36, $63\;{\mu}m$), and stored at $10^{\circ}C$ for 18 days. Thickness of polyethylene film was a significant factor for microorganisms populations and sensory attributes. Mesophilic aerobic bacterial count after 13 days for the control, packed in punched film bags, was $3.07{\times}10^6}$ CFU/g, while those for samples in hermetically sealed bags ranged only $1.74{\sim}2.02{\times}10^5}$ CFU/g. Gas composition within the sealed packages changed from normal air to about $1.3{\sim}5.4%\;O_2$ and $4.0{\sim}8.0%\;CO_2$ after 13 days of storage. Particularly, the visual sensory quality of cut green onion samples was retained better in polyethylene film bags of $63\;{\mu}m$ thickness(gas transmission rate: 600 $O_2\;mL/day{\cdot}m^2{\cdot}atm;\;2,500\;CO_2\;mL/day{\cdot}m^2{\cdot}atm$) than in the others.