• Food Science and Preservation
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• v.21 no.2
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• pp.239-245
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• 2014

This study was performed to provide fundamental information regarding the quality change of buckwheat soksungjang (BWS) during its storage. BWS was divided into three different containers (pot, plastic, and glass) and was stored at three different temperatures (5, 15, and $25^{\circ}C$), and the changes in pH, acidity, amino-type nitrogen, total bacterial count, and chromaticity were examined during the storage period. The pH (0 day, pH 4.37) and acidity (0 day, 2.93% acidity) of the samples, except at the 15 and $25^{\circ}C$ pots, did not show any significant change during storage, but 98 days after storage, the pH values of the 15 and $25^{\circ}C$ pots were pH 5.6 and 7.4, and their acidity values were 1.85 and 0.71%, respectively. At 98 days, the amino-type nitrogen of the $25^{\circ}C$ plastic sample had slightly increased to $0.75{\pm}0.01%$, and that of the $25^{\circ}C$ pot had drastically risen to $0.92{\pm}0.01%$. It was also shown that little change in the total bacterial count was found during the experiment period in every sample. The chromaticity results confirmed that the L (lightness), a (redness), and b (yellowness) values of the $25^{\circ}C$ pot sample showed relatively large changes during storage compared to the other samples. These results suggest that the desirable storage temperature of BWS is in the range of $5-15^{\circ}C$, and that a glass container is the most suitable container for BWS as it can reduce the quality alteration during storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.3
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• pp.291-306
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• 1984

The possibility of formation of carcinogenic N-nitrosamines such as nitrosodimethylamine(NDMA), nitrosodiethylamine (NDEA) and nitrosopyrolidine (NPYR) during the fermentation of Kimchi was investigated. Three different types of Kimchi, formulated with chinese cabbage, red pepper powder and garlic, with or without one of both fermented shrimp and anchovy juice, were cured for 75 days at $5^{\circ}C$. The changes in contents of nitrates, nitrites, pH, ascorbic acid, secondary amines, trimethyl-aminoxide (TMAO), trimethylamine (TMA) and NDMA were analyzed periodically during the fermentation. TMAO, TMA. DMA, nitrate, nitrite and ascorbic acid were analyzed by colorimetric methods, and NDMA, NPYR and NDEA were determined by the method of GLC-TEA. Although the total secondary amines markedly increased, no significant changes in the levels of TMAO and TMA were observed during the fermentation Kimchi added with fermented shrimp or anchovy juice. The predominating component of secondary amines was confirmed to be dimethylamine by means of nitrosating technique coupled with gas chromatography. No appreciable increase in the level of nitrites was appeared although nitrate level in the Kimchi apparently decreased. Non detectable or trace level of nitrosamine formation was detected whereas the nitrates fairly decreased during the fermentation of Kimchi. This could be explained by the fact that the lack of nitrites was resulted in the system due to rapid consumption of nitrites formed from nitrates by the reactions with ascorbic acid and amino acids which have been known as inhibitors of nitrosation reaction.

• The Korean Journal of Mycology
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• v.1 no.1
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• pp.3-11
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• 1973

Four species of nematodes attacking mushroom beds were found in samples taken from 35 mushroom farms throughout Korea. These were Rhabditis sp., Aphelenchoides sp., Ditylenchus sp. and Aphelenchus sp. ,Rhabditis sp. was found from compost and casing from all mushroom farms and the frequencies of Aphelenchoides sp. was 31.4% in the both compost and casing. Both Ditylenchus sp. and Aphelenchus sp. showed 2.7% of frequencies in the compost, none in casing. Temperature and moisture content of compost affected pathogenicity of Aphelenchoides sp. on mushroom mycelia grown in compost. The higher temperature and moisture content the sooner the damage became apparent, and the more rapid was subsequent destruction of mycelia. There was no mycelial destruction at the lowest temperature of $10^{\circ}C$. Rhabditis sp. completely disintegrated mycelia grown in the compost, in the early stage, the numbers of Rhabditis sp. rose gradually and then increased suddenly to reach a peak but soon declined. At first, the pH of Rhabditis-infested spawned compost declined but then rose gradually as mycelia was disintegrated by nematodes. The trend in pH of infested unspawned compost was similar to those of uninfested, unspawned compost. Cultures inoculated with surface-disinfected dead Rhabditis sp. and with tap water used in the nematode extraction procedures showed no mycelial injury associated microorganisms containing within or outside the nematodes even though added by artificial wounding of the mycelia. Cultures artificially wounded showed no injury away from the wounds without the presence of living Rhabditis sp., such wounded mycelia slowly regenerated. On the other hand, artificial wounding accelerated the breakdown of mycelia in the presence of living Rhabditis sp.

• Journal of Korea Society of Industrial Information Systems
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• v.12 no.5
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• pp.1-13
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• 2007

In this research, we found out that bridging nodes have great effect on the robustness of protein-protein interaction networks. Until now, many researchers have focused on node's degree as node's essentiality. Hub nodes in the scale-free network are very essential in the network robustness. Some researchers have tried to relate node's essentiality with node's betweenness centrality. These approaches with betweenness centrality are reasonable but there is a positive relation between node's degree and betweenness centrality value. So, there are no differences between two approaches. We first define a bridging node as the node with low connectivity and high betweenness value, we then verify that such a bridging node is a primary factor in the network robustness. For a biological network database from Internet, we demonstrate that the removal of bridging nodes defragment an entire network severally and the importance of the bridging nodes in the network robustness.

• Korean Journal of Food Science and Technology
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• v.10 no.1
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• pp.73-77
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• 1978

This experiment was made to select the optimum thickness of the polyethylene (P.E) film for Cheongdo Bansi and Sagoksi in the P.E film storage kept at $0^{\circ}C$. The experimental plots were divided into 4 plots by film thickness (0.04, 0.06, 0.08 and 0.10mm) and those were subdivided into 3 plots by fruits number (3, 10 and 50 persimmons) in each film bags. We investigated five experimental items; the change of loss of weight, firmness, titratable acidity, sugar contents and soluble tannin contents. 1. In the changes of loss of weight, the plot of packing in 0.04mm P.E. film bag with 50 persimmons were more retarded than other plots in Cheongdo Bansi, and packing in 0.08mm with 10 persimmons, 0.04 mm with 50 persimmons were more retarded than other plots in Sagoksi. 2. In the change of softening, the plot of packing in 0.04 mm with 50 persimmons were more retarded than other plots in Cheongdo Bansi and Sagkai. 3. In the changes of titratable acidity, the plot of packing in 0.04 mm with 50 persimmons were more slightly decreased than other plots in Cheongdo Bansu also in Sagoksi, packing in 0.06 mm with 10 persimmons were the same results. 4. In the changes of soluble tannin contents, the plots of packing in 0.06 mm with 10 persimmons, 0.04 mm with 50 perimmons were more ratarded in Chenongdo Bansi, also in Sagoksi, packing in 0.04 mm with 10 persimmons 50 persimmons were the same results. 5. In the changes of soluble tannin contents, the plots of packing in 0.04mm with 3 and 10 persimmons were more slowly decreased than other plots in Cheongdo Bansi and Sagoksi, on. the other hand, pcaking in 0.04mm with 50 persimmins in Cheongdo Bansi and Sagoksi, had not astringent taste at 120 days in storage. Judging through the upper results, the most desirable storage conditions for Cheongdo Bansi and Sagoksi were to pack in P.E film bag of 0.04mm with 50 persimmons.

• Journal of the Korean Institute of Landscape Architecture
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• v.14 no.2
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• pp.7-16
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• 1986

This study was carried out to investigate the effects of such erosion control measures as sowing, planting and small earth structures on the soil and vegetation. In order to study the changes in soil and vegetation, 36 plots were surveyed from 1981 to 1982 in the large erosion control area which is restored last 20 years. The factors which were measured included vegetation coverage, tree growth, number of species, soil depth, soil consistancy, and Chemical properties of soil. The results were as follows; 1) Maximum coverage of the overstory and understory was attained 7 years after the initiation of erosion control. So the overstory need to be tended and pruned. 2) Diversity of species increased until age 6 after which it began to decrease. 3) In order of tree growth, black locust was the fastest, followed by siberian alder and pitch pine. The initial growth of black locust, though the best among the 3 tree stop., decreased rapidly year by year. At the same time, siberian alder and pitch pine grew well until 12 and 6 years after the initiation of erosion control respectively. 4) Fifty percent of the initially planted trees died within 8 yeard. The mortality of siberian alder occurred until the 20th year while the mortality of pitch pine stopped after 10 years. Thereafter 500 trees per hectare were maintained. 5) The soil depth in A and B horision increased by 2cm annually during 20 years. The soil consistency also decreased rapidly until 7th year. The physical soil properties of the rehabilitated areas were improved after the 14th year. 6) The soil pH tend to decrease from 5.3 during the first year to 5.1 during the twentieth year. 7) The organic matter and nitrogen content in the soil were increased by fertilization but after 20 years these nutrients are still deficient for normal tree growth. 8) The phosphorous content in the soil was high in the first year but the longer the period after the initiation of erosion control the lese the content of phosphorous. 9) The biomass of black locust was the highest and increased continuously. The biomass of siberian alder on the contrary decreased from the 15th year because the number of trees in this place was very low. The total biomass in the twentieth year after erosion control initiation was 105.7 ton per hectare.

• Restorative Dentistry and Endodontics
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• v.36 no.4
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• pp.290-299
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• 2011

Objectives: The usage of fluoride varnish for a moderate to low caries-risk group has not been well validated. This study aimed to evaluate the preventive and therapeutic efficacies of fluoride varnish on the initiated root caries. Materials and Methods: Ten premolars were sectioned into quarters, further divided into two windows, one of which was painted with Fluor Protector (1,000 ppm fluoride, Ivoclar Vivadent). An initial lesion with a well-preserved surface layer was produced by pH cycling. Scanned line analysis using energy dispersive spectrometry determined the weight percentages of Ca and P in the demineralized layer. Scanning Electron microscopy and confocal laser scanning microscopy (CLSM) evaluated the varnish-applied root surfaces. Results: The mean lesion depth (SD) was 12.3 (2.6) ${\mu}m$ (single cycling) and 19.6 (3.8) ${\mu}m$ (double cycling). Double cycling extended the lesion depth, but induced no more mineral loss than single cycling (p < 0.05). The mean weight percentages of Ca and P between groups with and without varnish were not significantly different (p < 0.05). A CLSM showed varnish remained within 15 ${\mu}m$ of the surface layer. Conclusions: When a mild acid challenge initiated root tissue demineralization, the application of low-concentration fluoride varnish did not influence the lesion depth or the mineral composition of the subsurface lesion.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.2
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• pp.119-125
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• 2010

This study was carried out to compare the physicochemical characteristics of Korean traditional wine fermented from proso millet and nuruk at different mixing rate. The alcohol contents of the fermented wine ranged from 12.36 to 13.21%. Two kinds of nuruk, SH and BS nuruks were used. The brix degrees of proso millet wine fermented by SH and BS nuruks were 21.6 and 22.4 $^{\circ}Bx$, respectively. The pH, total acidity, and turbidity the wines fermented by SH and BS nuruks were 3.74 and 3.40, 1.40 and 1.51%, and 0.441 and 0.149, respectively. With increasing the addition amount of proso millet, brix degree, pH, turbidity L-value decreased, and total acidity and avalue increased. Total color difference (${\Delta}Eab$) parameter of the wine fermented by SH nuruk were 4.33, 6.63 and 26.13, and by BS nuruk were 4.08, 5.29 and 10.59 in 30, 70 and 100% addition rates of proso millet. With increasing the addition amount of proso millet, glucose content decreased. The organic acids such as lactic acid and acetic acid were predominantly detected in the fermented wine. Finally, based on sensory evaluations, the wine fermented by SH nuruk showed the best overall quality at 30% addition rate of proso millet.

• Journal of Animal Science and Technology
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• v.49 no.4
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• pp.491-500
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• 2007

Two experiments were used to determine the effects of environment-friendly diets on growth performance, fecal excretion, nitrogen excretion and emission gases in manure for growing pigs. In experiment 1, ninety six crossed pigs(Landrace×Yorkshire×Duroc) were allocated into four treatments. Treatments were AME(adequate ME diet, 3,265 kcal/kg), LME(lower ME diet, 3,100 kcal/kg), LME 0.05(lower ME diet+α- galactosidase & β-mannanase 0.05%) and LME 0.10(lower ME diet+α-galactosidase & β-mannanase 0.10%). Pigs fed AME diet had lower ADFI(Average Daily Feed Intake) than pigs fed other diets(p<0.05). DM(Dry Matter) digestibility in pigs fed AME and LME 0.10 diets had greater than pigs fed LME diet(p<0.05). Energy digestibility is higher in pigs fed AME and LME 0.10 diets than other treatments(p<0.05). In experiment 2, twenty four crossbred pigs(33.71 kg average BW) were used in a 14-d metabolism experiment. The pigs were housed in individual cages equipped with plastic bed flooring. Treatments were CP(Crude protein) 18% without Bacillus sp., CP 18% diet+Bacillus sp. 0.05%, CP 14% without Bacillus sp. and CP 14% diet+Bacillus sp. 0.05%. Nitrogen intake was higher for CP 18% diets than CP 14% diets(p<0.05). DM, N(Nitrogen) and energy digestibility were affected by probiotics(p<0.05). With the high CP in diets, Energy and N digestibility, urine N percent, urine N excretion and total N excretion were increased significantly compared to low CP in diets(p<0.05). Among the treatments, DM and N digestibilities, feces N excretion, N absorption were decreased significantly(p<0.05), however, feces excretion, feces N, urine N percent, urine N excretion and total N excretion were increased significantly(p<0.05) when pigs fed without probiotics diets compare to pigs fed with probiotics diets. DM and N digestibility, feces excretion, feces N excretion, urine N percent, urine N excretion, total N excretion, N absorption and N adsorption ratio were CP×probiotic interactions in p<0.05. Ammonia(p<0.01) and H2S(p<0.05) in manure were lower in CP 14% diets than CP 18% diets. Also, ammonia and H2S in manure were CP×probiotic interactions in p<0.05. In conclusion, low energy and reduction of CP dietary added enzyme and probiotics improved nutrient digestibility and reduced odors emission in manure for growing pigs.

• Applied Biological Chemistry
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• v.7
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• pp.21-27
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• 1966

This experiment was performed to investigate the effect of the frequency of meals on the metatolism and the body composition of rats when equal amount of purified diet was ingested. Thirty approximately days old rats weighing 290 g and thirty-two about 40 days old rats weighing 180 g were employed for the period of 34 days. Rats fed ad libitum (10 to 15 meals per day) and two-meal per day were pair-fed and equal amount of diet was fed to each rat in pair. The experimental results obtained are summarized as follows: 1. Frequency of meal did not exert any effect on the body weight gain. However, rats fed two-meal per· day gained significantly (p <0.005) more fat and energy than ad libitum group. The rate of gain of protein in ad libitum group was higher than that of two-meal group. No difference was observed for the mineral deposition of rat body. 2. From the preperation of rat liver it was found that the activity of glucose-6-phosphate dehydrogenase was much higher for the rats fed two-meals per day than those fed ad libitum. Therefore, it is suggested that the metabolic pathway of carbohydrate for two-meal group has been shifted from glycolysis to Hexose Monophosphate Shunt and produced more NADPH which would be the essential cofactor of fatty acids synthesis. 3. The rate of excretion of urinary nitrogen for two-meal group was significantly (p<0.005) higher than that of ad libitum group. It is apparent that considerable amount of over-loaded amino acids by feeding two-big-meal daily· could not be used for the protein biosynthesis all at once and excreted following deamination through urine. The residual carbon chain could be served as a precursor of fatty acids synthesis. 4. The heat production rate of rats fed two-meal group was significantly (p<0.005) lower than that of ad libitum group. It seems possible that the activity of thyroid gland (and consequently BMR) can be depressed by the frequency of meal.