• Korean Journal of Community Nutrition
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• v.5 no.4
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• pp.633-641
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• 2000

This study was conducted to measure the difference in the total antioxidant status(TAS) of overweight and normal weight adults, and to investigate the correlation between TAS and the nutrient intake. Anthropometric parameter, TAS, biochemical parameters and dietary intake were measured in the normal weight group(n=17, BMI 20-25, obesity index 90-110%, body fat 16-20%) and overweight group(n=13, BMI > 25, obesity index > 120%, body fat > 25%) among Korean young males. The TAS of the overweight group was significantly higher than that of the normal weight group(p < 0.01). Among biochemical parameters, the average uric acid concentration of the overweight group was significantly higher(p < 0.05) compared to that of the normal weight group indicating, the uric acid concentration reflects TAS. Usual dietary intake showed that the intakes of Ca and vitamin B$_2$, are below RDA. The average intake of vitamin C in the overweight group was significantly lower than that in the normal group(p < 0.05). There was no difference in the intake of carotene and vitamin E between groups. The diet quality of both groups was satisfactory. The result of the correlation analysis on TAS, the uric acid concentration, and the measured indexs are as follows : In the overweight group, TAS was negatively correlated with alchol drinking, and uric acid concentration was positively correlated with BMI, obesity index, and TAS. In conclusion, TAS was significantly higher in the overweight group than that of the normal group, although no association was found with nutrient intakes. Serum uric acid showed a positive relationship with TAS indicating, it is a possible determinant of the antioxidant capacity.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.6 no.4
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• pp.413-420
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• 1994

Dynamics of the river plume is a very complicated non-linear problem with the free boundary changing in time and space. Mixing with the ambient water through the boundary makes the problem more complicated. In this paper we reduced 3-dimensional problem into 1-dimensional one by using the integral analysis method. Basic equations have been integrated over the lateral and vertical variations. For these integrations we adopted the well-established assumption that the flow-axis component of plume velocity and the density difference of the plume with the ambient water have Gaussian distributions in directions which are perpendicular to the flow-axis of the plume. We also used the result of our previous study on the lateral spreading velocity of the plume derived under the same assumption. And entrainment was included as a mixing process. The resultant 1-dimensional equations were solved by Runge-Kutta numerical method. Consequently, comparatively easy method of numerical analysis is presented for the 3-dimensional river plume. The method can also be used for the analysis of the thermal plume of cooling water of power plants.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.2
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• pp.125-136
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• 1981

This experiment was conducted to study the influence of different cultivation periods on some morphological and agronomic characteristics of rice plant at Iri, the Honam plain, in 1979. Early maturing varieties showed little delay in heading with late transplanting, but intermediate and late maturing varieties showed more than 7 day delay in heading. The number of days required to reach heading was over 55 and 67 days after transplanting in early and intermediate-late maturing varieties, respectively. There was significantly postitive correlation between the length of vegetative stage and the grain yield. The mean temperature during ripening period was significantly correlated with the grain yield and the percentage of filled grains. The length, width, and thickness of leaf increased with earlier transplanting and the elongation degree between upper and lower leaves showed the same tendency. The productivity of dry matter and the translocation rate of photosynthate to spikelet decreased with late transplanting mainly due to low temperature. LAI was also influenced by transplanting date showing close correlation with yield. Early transplanting was desirable for assimilation and dry matter accumulation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.2
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• pp.167-173
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• 1981

Respiration of whole seeds and seed parts isolated from four soybean varieties Essex, Pickett, Wayne and Bonus as measured at $25^{\circ}C$ during germination. The average respiration rates of cotyledons were significantly higher than those of other parts. The values were 35.7, 28.0 and $23.9{\mu}hr^{-1}$ seed$^{-1}$ for cotyledons, embyros, and hila, respectively. Bonus showed a significantly lower respiration rate than the other varieties did. The interaction of variety x seed part was not significant source of variation for respiration. This suggests that seed part and variety independently contribute to soybean seed respiration during early imbibition. The effects of imbibition time and time x variety intereaction on whole seed respiration were significant, but the variety effect was not significant. The correlation coefficient between seed moisture content and respiration after 24 hours of imbibition was significant for Bonus, but not for the other varieties tested. This suggests that Bonus may require more water for respiration during imbibition than the other varieties. There as no significant correlation of whole seed respiration rate after 24 hours imbibition with seed weight or seedling length.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.2
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• pp.157-166
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• 1981

Laboratory experiements were conducted to evaluate water uptake and osmotic potential of soybean seeds associated with germinability. Bonus, Wayne, Essex and Pickett were selected for this study. Large and small seeds from the four varieties were included in water uptake measurements at $25^{\circ}C$ There were significant differences in water uptake during germination due to seed size and cultivars at optimum moisture condition, -6 and -15 bars soil moisture. As water stress increased, the water uptake of Pickett and Essex were superior to Bonus and Wayne, and small seeds were superior to large seeds. The seed moisture content at germination was 60.8% on a fresh weight basis under optimum moisture condition. The minimum moisture contents necessary for the germination were 50.2% at -6 bars and 50.9% at -15 bars. There were significant differences among varieties in seed osmotic potential during germination, although these differences depended on imbibition time. The average osmotic potential ranged from -32.0 bars after 4 hours imbibition to -11.2 bars at the beginning of germination. The correlation coefficient between seedling length and osmotic potential was not significant after any period of imbibition, suggesting that osmotic potential is not directly associated with seedling growth. However, osmotic potential is closely related to water uptake capacity of soybean seed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.1
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• pp.1-6
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• 2012

In this study, we conducted to identify predictive parameters affecting the head rice ratio for developing high quality rice cultivar adaptable to the early-transplanting cultivation. The recombinant inbred lines (RILs) population from a cross between the parents of Pungmi and Koshihikari was used for test materials. Variations were observed in most of the measurements, eg culm length (ranging from 51.0 cm to 97.0 cm), amylose content (14.0~20.1%), protein content (5.2~7.4%), pasting properties (peak viscosity, 227.2~309.8 RVU) and head rice ratio (67.7~96.7%). Significant correlations between head rice ratio versus culm length (0.443) and head rice ratio versus protein content (-0.458) were detected in RIL population. However, culm length was negatively related to lodging tolerance. In order to develop a commercially suitable cultivar, selection for short culm and high head rice ratio of rice grains with physiochemical properties such as protein content, amylase content and taste value should be considered. This results can be used to increase the efficiency of breeding program for developing a new early-maturing rice variety adaptable to early transplanting cultivation in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.4
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• pp.382-387
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• 2008

This study was conducted to determine the effect of rice bran on rice yield, grain quality and weeds control depending on applying times. The redox potential was severely reduced $4{\sim}7$ days after rice bran application but that of conventional practice was reduced 17 days after transplanting. During the decomposing of the rice bran in the water, the dissolved oxygen in the water was exhausted right away after rice bran application. The dry weight of weed increased as the rice bran application time was delayed that weed dry weights increased by 138% in applying before puddling (ABP), 219% in 5 DAT (days after transplanting), 300% in 7 DAT and 619% in 9 DAT compared to conventional practice. The rice yield reduced remarkably in rice bran treatments after transplanting compared to conventional practice and applying before puddling. In the rice quality, the head rice ratio in the rice bran treatment was higher than that in conventional practice, and its protein content decreased. The results confirm that the rice bran application make the rice palatability higher, but there was no difference in rice qualities depending on application times.

• Microbiology and Biotechnology Letters
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• v.40 no.1
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• pp.70-75
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• 2012

In Salmonella enterica, many genes encoded within Salmonella pathogenicity islands (SPI) 1 and 2 are required to cause a range of diseases in a variety of hosts. The SPI1-encoded regulator HilD activates both the SPI1 and 2 genes at different times during growth in Luria-Bertani (LB) media. In this study, the expression levels of hilD during growth in LB were investigated. The data suggest that hilD expression is induced in the early stationary phase and decreases in the late stationary phase, when sseA, an SPI2 gene, is maximally expressed. However, HilD could act as an activator of sseA expression in the late stationary phase despite being present at low levels. SseA expression was investigated in SPI1 regulator mutant strains, hilA, hilD and invF mutants. As expected, hilD mutation decreased sseA expression. However, we found that invF mutation caused a 1.5-fold increase in sseA expression in not only LB but also M9 minimal media, which is thought to resemble an intracellular environment. InvF overexpression restored sseA expression to wild-type levels in an invF mutant but did not cause an additional reduction in sseA expression. These results suggest that SPI1 controls SPI2 expression either positively or negatively.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.103-111
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• 2000

Ozonation and advanced oxidation($H_2O_2/O_3$) process were investigated under various experimental conditions to improve the efficiency of biological filter used for the treatment of recycled wastewater from aquaculture. Ammonia removal followed the first-order reaction whose reaction rate constant(k) was $2.0{\times}10^{-2}min^{-1}$ in ozonation. The ammonia removal rate increased according as the bicarbonate alkalinity is increased. About 46% $NH_3$ was oxidized by ozone at 200 mg/L as $CaCO_3$. When alkalinity existed in wastewater, ammonia removal rate by advanced oxidation was very low due to the inhibition effect of bicarbonate. However, when initial pH was adjusted to about 8.2 by 0.1 N KOH, ammonia removal rate was improved higher than that by ozonation. Especially. ammonia removal rate was the highest at $H_2O_2/O_3$ of 0.25 and about 90% of ammonia was removed in 30 min at this ratio as pH was maintained over 9. In the case of wastewater containing ammonia and organic constituents, ammonia removal efficiency by both ozonation and advanced oxidation decreased seriously because organic constituents consumed the oxidant faster than ammonia. In addition the optimal $H_2O_2/O_3$ ratio was changed. Like ammonia removal, DOC(dissolved organic carbon) increased for first 10 min and then decreased slowly because the particulate organic constituents were oxidized rapidly and then produce DOC. Even when the ammonia concentration by twice, oxidation of DOC was not retarded.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.10
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• pp.710-716
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• 2013

New and renewable energy sources have drawn attention because of climate change. Many studies have been carried out in waste-to-energy field. Fast pyrolysis of waste lignocelluosic biomass is one of the waste-to-energy technologies. Bubbling fluidized bed (BFB) reactor is widely used for fast pyrolysis of the biomass. In BFB pyrolyzer, bubble behavior influences on the chemical reaction. Accordingly, in the present study, hydrodynamic characteristics and fast pyrolysis reaction of waste lignocellulosic biomass occurring in a BFB pyrolyzer are scrutinized. The computational fluid dynamics (CFD) simulation of the fast pyrolysis reactor is carried out by using Eulerian-Granular approach. And two-stage semi-global kinetics is applied for modeling the fast pyrolysis reaction of waste lignocellulosic biomass. To summarize, generation and ascendant motion of bubbles in the bed affect particle behavior. Thus biomass particles are well mixed with hot sand and consequent rapid heat transfer occurs from sand to biomass particles. As a result, primary reaction is observed throughout the bed. And reaction rate of tar formation is the highest. Consequently, tar accounts for 66wt.% of the product gas. However, secondary reaction occurs mostly in the freeboard. Therefore, it is considered that bubble behavior and particle motions hardly influences on the secondary reaction.