• Korean Journal of Veterinary Research
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• v.9 no.1
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• pp.63-69
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• 1969

Various methods for the isolation of salmonellae were compared by examining mesenteric lymph nodes and faeces of 395 pigs at slaughter. The conclusions were as follows. (i) Tetrathionate broth was significantly superior to selenite broth for the examination of mesenteric lymph nodes. (ii) There was no significant difference between tetrathionate broth and selenite broth for the examination of faeces. The use of both tetrathionate broth and selenite broth as enrichment media for faeces produced far better results than the use of any single enrichment medium. (iii) Brilliant green agar was significantly superior to SS agar for the examination of mesenteric lymph nodes. (iv) There was no significant difference between brilliant green agar and SS agar when faeces were examined. The use of both media produced far better results than the use of either singly. (v) Brilliant green MacConkey broth was much inferior to tetrathionate broth as an enrichment broth. Direct culture of faeces on brilliant green MacConkey agar yielded less isolates than prior enrichment in tetrathionate or selenite broth. (vi) The optimum incubation period of enrichment was 24 hours for faeces and 48 hours for mesenteric lymph nodes when either tetrathionate broth or selenite broth was used as enrichment media.

• Preventive Nutrition and Food Science
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• v.14 no.2
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• pp.142-147
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• 2009

In this study, the selenium (Se) accumulations of soybean sprouts and mungbean sprouts treated with various concentrations of Se-solutions were evaluated, as part of a broader effort to produce Se-enriched variants of the plants. Four levels of sodium selenate ($Na_{2}SeO_{4}$)-dissolved solutions (i.e. 0, T0; 6, T1; 60, T2; and $600{\mu}g/mL$, T3) were prepared and sprayed onto the plants during cultivation. The effect of different spraying periods on Se accumulation was also assessed by watering plant groups once a day for periods of one, two, or three days. Se solution remaining on the surfaces of the plants was washed out by spraying with distilled water on the final day of cultivation. However, the increase of Se accumulation in the plants was found to depend on both Se-concentration and watering period, and the soybean sprouts were determined to accumulate Se more effectively than the mungbean sprouts. Additionally, with regard to Se accumulation in the plants, the period of application of Se solution was determined to be more important than the concentration of the Se solution applied. The averaged total levels of Se-enrichment in whole soybean sprouts at T0, T1, T2, and T3 were 0.26, 65.86, 179.62, and $525.12{\mu}g/dry$ matter (DM) g, respectively, and the relative equations relating Se enrichment in soybean sprouts (Y) against watering days (X) were Y=32.505X-36.17 (T1), Y=88.46X-92.04 (T2), and Y=251.11X-254.9(T3). The averaged total levels of Se-enrichment in the whole mungbean sprouts at T1, T2, and T3 group were 0.05, 3.64, and $101.43{\mu}g/DM$ g, respectively, and the relative equations relating Se enrichment (Y) to watering days (X) for mungbean sprouts were Y=1.67X-1.3467 at T1 and Y=48.035X-46.907 at T2. The results of this study suggest that soybean sprouts and mungbean sprouts enriched with bioavailable Se can be produced on a large scale by Se supplementation, allowing for the development of healthy functional foods such as Se-enriched mungbean sprout soups and salads, Se-enriched functional drink and food additives, and selenium tablets to promote health.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.6
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• pp.879-886
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• 2016

As is in all economic activities, the highest yield per unit area is the main goal in animal production, while addressing the temperamental needs of animals often is ignored. Animal welfare is not only an ethical fact; it also has an economic value. Spatial environmental enrichment contributes positively to animal welfare by addressing their behavioral and mental requirements. The present study was conducted to determine the effects of weaning and spatial environmental arrangements on behaviors of goat-kids. Experimental groups were arranged in structured and unstructured spatial environments. Roughage feeder, semi-automatic concentrate feeder, bunk, bridge, and wood block were placed in the structured environment. No equipment was placed in the unstructured environment and paddock sides were enclosed with an iron sheet to prevent bipedal stance and to provide environmental isolation. In the study 10 male and 10 female Turkish Saanen goat kids were used in each group. Spatial environmental arrangements did not have significant impacts on the growth performance of kids (p>0.05). All objects in the structured group were accepted by the kids. Average use ratios of roughage feeder, semi-automatic concentrate feeder, bunk, bridge and wood block were observed as 19.3%, 14.0%, 12.6%, 3.8%, and 0.7%, respectively. There were significant differences between before- and after-weaning in use of all objects except for underneath bridge ($p{\leq}0.05$). Concentrate feed consumption, locomotion, and resting behaviors in kids showed significant differences by structural group and growth period. Roughage consumption was similar between groups, while it differed by growth period ($p{\leq}0.05$). Interaction frequency was significantly higher in structured group (p = 0.0023). Playing behavior significantly differentiated based on the growth period rather than on groups ($p{\leq}0.05$). Playing behavior significantly decreased after weaning. Abnormal oral activity was significantly higher in the structured group before weaning ($p{\leq}0.05$). Despite there being no installations facilitating climbing and bipedal stance, the kids of the unstructured group were able to exhibit 1/3 as much bipedal stance behavior as the kids of the structured group through leaning over slippery paddock wall or over their groupmates. Bipedal stance behavior of unstructured group was similar before and after weaning, while bipedal stance behavior before weaning was about 2 times that of after weaning in structured group. It was concluded that unstructured environmental arrangement limited the behavior repertoire of the goat kids.

• Korean Journal of Medicinal Crop Science
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• v.8 no.1
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• pp.14-20
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• 2000

This experiment was conducted to investigate the effects of length of storage period under low temperature, $CO_2$ enrichment and addition of plant growth regulators in Murashige and Skoog medium on the plant regeneration of Korean ginseng (Panax ginseng C. A. Meyer). Seeds were treated for 60 and 80 days respectively under $5^{\circ}C$ environment. 2500ppm of $CO_2$ was enriched by ventilation. Three plant growth regulators added to the medium were Indolbutyric acid, Benzyladenin and Gibberellic acid (GA3). The result indicated that : The capacity of differentiation was higher in the aged cotyledons from the seeds treated for 80 days under low temperature condition than in those treated for 60 days. $CO_2$ enrichment had stimulating effects on the growth and development of shoot primordium significantly but less effects on the formation of adventitious buds. From one zygotic embryo hundreds of plantlets were differentiated. $CO_2$ enrichment had effects on the formation of both indirect somatic embryo and direct somatic embryo. Indirect somatic embryo showed little growth and differentiation, being undifferentiated vascular stele and epicotyl. Direct somatic embryos were formed on the epidermis of backside basal part of cotyledon. Those embryos developed to whole plant having latent bud.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.529-532
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• 2001

Korean food waste, one of the abundantly available but environmentally problematic organic wastes in Korea, was utilized as solid-substrate by fungal strain Aspergillus niger ATcC 6275 for the production of enzymemixture containing amylase, cellulase and xylanase. The enzyme mixture can be used as high value-added animal feed. Solid-state fermentation method yielded a 84-fold enhancement in xylanase activity compared with submerged fermentation method. The effect of incubation period, incubation temperature, pH of medium, moisture content, inoculum size and enrichment of the medium with nitrogen and carbon sources were observed for optimal production of these enzymes The optimal amylase activity of 33.10 U/g, cellulase activity of 24.41 U/g, xylanase activity of 328.84 U/g were obtained at 8 days incubation with 50%(w/w) soy bean flake, with incubation temperature of $25^{\circ}C$, pH of 6.38, optimal moisture content of 55% and with inoculum size of $3.8{\times}10^6$spore/g. Enzyme activities were enhanced when ImM $CaSO_4$, 2% Malt extract and 2% galactose were added as mineral, nitrogen and carbon enrichment respectively.

• Journal of The Korean Astronomical Society
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• v.15 no.2
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• pp.71-77
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• 1982

According to the star formation rate and metal enrichment rate given by the disk-halo model of Lee and Ann (1981), the two different forms of time-dependent initial mass function (IMF) and the present day mass function (PDMF) of nearby stars have been examined. It was shown that the constraint for the initial rapid metal enrichment requires the time-dependence of IMF at the very early phase ($t{\lesssim}5{\times}10^8$ yrs) of the solar neighborhood. The computed PDMF's show that the PDMF is nearly independent of any specific functional form of IMF as long as the latter includes a Gaussian distribution of log m. This result is due to the very small fractional mass $({\times}5%)$ of stars formed at the very early period during which the IMF is time-dependent. The computed PDMF suggests the presence of more numerous low mass stars than shown in Miller and Scalo's (1979) PDMF, supporting the possibility of the existence of low-velocity M dwarfs. According to the number distribution of stars with respect to [Fe/H], the mean age of these low mass star must be very old so as to yield the mean metal abundance $\bar{[Fe/H]}{\approx}-0.15$ for the stars in the solar neighborhood.

• Journal of Environmental Science International
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• v.19 no.7
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• pp.799-806
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• 2010

In an effort to characterize temporal and spatial variability of $PM_{10}$ and to quantitatively estimate contribution of sea salt aerosol to $PM_{10}$ mass in Busan area, twenty four-hour averaged concentration of $PM_{10}$ were measured in two distinct areas, Gwaebeopdong(inland) and Dongsamdong(seashore), Busan for summer and fall, 2007. It was found that sea salt accounted for 2.9% and 9.5% of $PM_{10}$ mass in Gwaebeopdong and Dongsamdong, respectively for the study period, indicating that contribution of sea salt to $PM_{10}$ mass and total ion concentration in seashore area were consistently higher by a factor of three compared to inland area. Temporal analysis suggested that sea salt contributions to $PM_{10}$ in Dongsamdong were higher in summer due to the southerly sea breeze while there was no significant fluctuation of sea salt contribution for the summer and fall months in Gwaebeopdong. Sea salt enrichment factors($EF_{sea}$) of $K^+$ $Ca^{2+}$ and ${SO_4}^{2-}$ (>10) indicated major contributions from anthropogenic sources and EFs of $Mg^{2+}$ and $Cl^-$ exhibited strong association with oceanic origins for both areas.

• Journal of the Korean institute of surface engineering
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• v.56 no.1
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• pp.84-93
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• 2023

The spent nuclear fuel is burned during the planned cycle in the plant and then generates elements such as actinide series, fission products, and plutonium with a long half-life. An 'interim storage' step is needed to manage the high radioactivity and heat emitted by nuclides until permanent-disposal. In the case of Korea, there is no space to dispose of high-level radioactive waste after use, so there is a need for a period of time using interim storage. Therefore, the intensity of neutrons and gamma-ray must be determined to ensure the integrity of spent nuclear fuel during interim storage. In particular, the most important thing in spent nuclear fuel is burnup evaluation, estimation of the source term of neutrons and gamma-ray is regarded as a reference measurement of the burnup evaluation. In this study, an analysis of spent nuclear fuel was conducted by setting up a virtual fuel burnup case based on CE16×16 fuel to check the total amount and spectrum of neutron, gamma radiation produced. The correlation between BU (burnup), IE (enrichment), and CT (cooling time) will be identified through spent nuclear fuel burnup calculation. In addition, the composition of nuclide inventory, actinide and fission products can be identified.

• Journal of Aquaculture
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• v.11 no.4
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• pp.437-447
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• 1998

In mass production of larval rockfish, Sebastes schlegeli, high mortality had been observed frequently. This may be the consequence of the low nutritional quality of the live feeds used. This experiment was designed to find out a suitable diet for the mass production of rockfish larvae. Three kinds of live feeds were tested ; plutei of sea urchin (Hemicentrotus pulcherrimus), L-type rotifers (Brachionus plicatiilis) and Artemia naupii. The latter two were enriched with ${\omega}$-yeast, Spirulina platensis and Super Selco before feeding to rockfish larvae. The sea urchin plutei caused to poor survival and growth rates for larval rockfish, and therefore, they were not seemed as proper feed for rockfish larvae. Enrichments of rotifers and Artemia nauplii with ${\omega}$-yeast, Spirulina platensis, or Super Selco improved survival and growth rate. But, rotifers enriched with Super Selco resulted in better rockfish larvae survival than those enriched with ${\omega}$-yeast. A sudden increase of mortality occurred around 11 days after birth. In this critical period, a shift feed such as Artemia nauplii had been supplemented with rotifers. After this critical transition period, the moratality gradually decreased by feeding Artemia nauplii enriched with PUFA. Feeding of mixed feed with rotifers and Artemia nauplii resulted in better larval survival and growth than those of each live food alone.

• Journal of Ecology and Environment
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• v.38 no.3
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• pp.293-305
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• 2015

In order to understand the mechanisms of conversion between different algal dominance, an experiment was performed in a greenhouse from 22 June to 10 July 2011. The experiment included a treatment group subjected to three instances of nutrient enrichment and a control with no nutrient enrichment. The initial water was dominated by Ankistrodesmus of Chlorophyta. The average water temperature at 08:30 h and 14:00 h during the experiment was $31.6^{\circ}C$ and $34.6^{\circ}C$, respectively. The results showed that the total nitrogen (TN), total phosphorus (TP), dissolved total nitrogen (DTN), dissolved total phosphorus (DTP), and soluble reactive phosphorus (SRP) concentrations in the treatment were significantly higher than in the control (P < 0.05). However, the TN/TP and DTN/DTP in the control was higher than in the treatment (P < 0.05). The dominant algae in the control did not change during the experiment, while the dominant algae in the treatment switched to Planktothrix of Cyanophyta on day 9. The chlorophyll a (Chl-a), wet weight of all algae, wet weight of Cyanophyta, and percentage of Cyanophyta in the control were all significantly lower than in the treatment (P < 0.05). Amounts of zooplankton, especially rotifers, were present at the end of the experimental period. The density of rotifers between the control and treatment was not significantly different (P > 0.05), while the copepod density in the treatment was higher than in the control (P < 0.05). We conclude that green algae dominance quickly switches to cyanobacteria dominance after nutrient enrichment in a greenhouse with elevated temperature.