• Korean Journal of Agricultural Science
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• v.37 no.2
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• pp.199-207
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• 2010

This research was conducted to determine the influence of physiological and chemical properties of root substrates on the growth of the daughter plants of 'Maehyang' strawberry produced by bag culture. The daughter plants produced by stock plants during bag culture were individually separated and grown in 10-cm diameter plastic pots containing six different formulations of root substrates: a) 50% peatmoss plus 50% vermiculite (5:5 by volume, A), b) 70% peatmoss plus 30% perlite (7:3, B), c) 70% coir dust plus 30% perlite (7:3, C), d) mixture of 35% coir dust, 35% peatmoss, and 30% perlite (3.5:3.5:3.0, D), e) mixture of 20% rice hull, 70% coir dust, and 10% perlite (2:7:1, E), and f) 30% rice hull plus 70% coir dust (30:70, F). The container capacity and air filled porosity of the growing medium varied greatly among the six substrate formulations evaluated. The substrates E and F had less container capacity and higher air-holding spaces than the rest of the formulations. Therefore, these two formulations (E and F) may cause a problem in water management during the production of healthy daughter plants. The substrate formulations A, B, and D retained higher nitrogen (N) concentrations than other formulations containing coir dust or rice hull. The substrate formulations E and F which contained rice hull had lower N, phosphorus (P), and potassium(K) concentrations than other substrate formulations containing coir. The quality of the daughter plants grown in all six different substrate formulations was good with the crown diameters at around 10 mm. Fresh weights of the daughter plants grown in substrate formulations A, C, and D were higher than those obtained from B, E, and F. Dry weights of the daughter plants showed a similar trend. The daughter plants having high fresh and dry weights and increased crown diameter are in demand by the industry. For this reason, the substrate formulations A, C and D can readily be used as potting mixes during the production of 'Maehyang' strawberry transplants utilizing the bag culture system.

• The Korean Journal of Ecology
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• v.23 no.5
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• pp.397-406
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• 2000

In order to clarify the ecophysiological characteristics of Chenopodiaceae which widely distribute on saline and arid habitats, we collected 10 chenopodiaceous plant species, examined their inorganic and organic solute patterns, and confirmed several common physiological characteristics. In spite of high soil Ca/sup 2＋/ contents, chenopodiaceous plants had a little water-soluble Ca within cells, but contained high contents of acid-soluble Ca particularly as a result of Ca-oxalate formation. These plant species also showed accumulation of inorganic ions such as K/sup ＋/, NO₃/sup －/ and Cl/sup －/, and Na/sup ＋/especially in saline habitats instead of K/sup ＋/ Meanwhile, with respect to nitrogen metabolism they retained high N contents in leaves, but showed very low amino acid contents. Additionally, they contained very little proline known to act as a cytoplasmic osmolyte. To ascertain whether this physiological characteristics in the field also can be found under controlled conditions, 7 chenopodiaceous plants (Atriplex gmelini, Corispermum stauntonii, Salicornia herbacea, Suaeda aspayagoides, Suaeda japonica, Chenopodium album var. centrorubrum, C. serotinum) were selected and cultivated under salt treatments. As well as field-grown plants, selected plant species showed similar solute pattern in growth experiment. In summary, the family of Chenopodiaceae represents the following physiological properties; high storage capacity for inorganic ions (especially alkali cations, nitrate and chloride), oxalate synthesis to maintain lower soluble Ca contents within cytoplasm, and low contents of amino acids. In addition to some characteristics mentioned above, the physiological plasticities of Chenopodiaceae which can properly regulate their ion and solute pattern according to soil conditions may enable its representative to grow in dry sand dune and salt marsh habitats.

• Korean Journal of Food Science and Technology
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• v.8 no.1
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• pp.19-32
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• 1976

The laboratory Mejus as well as home-made Meju and improved Meju received from Korea were ripened in the brine for up to 8 months and the changes is the chemical composition during the process were determined and the differences between the types of Meju were compared. On the basis of the amino acid pattern, the changes in the protein quality of soybean during the process was evaluated. No significant changes in the general chemical composition of Meju were noticed during the ripening for 8 months. However, the nitrogen solubility of Meju increased for $13{\sim}29%$ to $66{\sim}78%$ during 8 month ripening of the Meju-brine mixture. The concentration of free amino-N to the total-N increased from $4{\sim}7%$ in Meju to $29{\sim}35%$ in the 8month ripened mixture. The concentration of amino-N to the total-N increased from $1{\sim}4%$ in Meju to $5{\sim}14%$ in the 8month ripened mixture and the changes varied with the type of Meju used. Remarkable changes in the amino acid pattern of soybean were occured during the ripening process. The concentration of methionine decreased to the half of original Meju during the first month of ripening. Arginine and histidine were destroyed rapidly by the ripening longer than 1 month. A considerable amount of ornithine was synthesized during the ripening. The amino acid pattern of Meju did change drastically during the ripening longer than 3 months and the changes varied with the type of Meju. The retention of the nutrients in soybean during 8 month ripening of the laboratory 3 month Meju in the brine was 49% for carbohydrates, 107% for crude fat, 93% for crude protein and 74% for the total amino acid. Histidine, arginine and methionine and 74% for the total amino acid. Histidine, arginine and methionine were the most damaged during the process, retaining only 25%, 27% and 49% of the contents in raw soybean, respectively, whereas lysine retained 79%. By the separation of the 8 month ripened mixture, approximately 60% of crude protein, all of crude fat and 80% of carbohydrates in the mixture were retained in soypaste. Soypaste contained higher concentrations of amino acids per 16gN compared to soysauce, except for lysine. The most limiting amino acid of the protein was the S-containing amino acids in all cases studied, whereas the second limiting amino acid varied from valine in soybean to threonine in most of Mejus and the brine mixtures, lysine in most of soypastes and tryptophan in some of soysauces. According to the protein quality evaluation made by the reference of the FAO provisional pattern of amino acid, the chemical score of raw soybean was 82, which was reduced to 77 by cooking and further reduced to $71{\sim}74$ by Meju fermentation. At the eighth month of ripening the chemical score of the Meju-brine mixtures were reduced to $51{\sim}66. After the separation, the chemical score of soypaste ranged from 60 to 71, whereas that of soysauce varied from 45 to 57. Generally, the products made from improved Meju recorded the highest score, whereas those made from homemade Meju showed the poorest protein quality. The essential amino acid index(EAAI) of the samples was similar to the chemical score, but it appeared to fit the overall changes in the amino acid pattern during the process better than the chemical score.

• Korean Journal of Poultry Science
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• v.6 no.2
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• pp.83-90
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• 1979

In order to evaluate the effect of lipids on the utilization of the energy and Protein of the diet, the isocaloric and isoprotein diets added with mutton fat, tallow, and lecithin at the levels of two percent and five percent were prepared. The growth of chicken and the feed efficiency were observed on hatched chicken which were fed a commercial diet for the first week, with starters for the next four weeks, and with finisher diets for the last three weeks respectively during the eight weeks of the experiment. Growth rate, feed efficiency, and average body weight gain per day were similar among the chicken fed diets containing various lipids or at the levels of two percent and five percent. The metabolizable energy of the diets was found to be from 2.713kcal to 3.059kcal per gram, and the metabolizability of the gross energy was from 62 percent to 70 percent. Also the metabolizability of basal diet was higher as compared with the diets containing lipids. And the lower energy utilization was found in the broilers fed diets containing five percent lipids than those of two percent, showing not significant difference between them. Daily metabolizable energy of three week old birds ranged from 132kca1 to 168kcal which resulted in also a tendency of lower values in the five percent diets. And daily retained nitrogen of birds ranged from 0.631 gr to 0.738 gr, which showed an increasing tendency on the birds fed five percent mutton fat and tallow in comparison with those of two percent. But the lecithin brought about a reverse tendency. The digestibility of crude fats was found to be from 48 percent to 76 percent, but not significant difference among diets plus lipids or at the levels of two percent and five percent. The birds fed five percent mutton fat and tallow showed a tendency of lower digestibility as. compared with those fed two percent, but the similar results were found between two percent and five percent lecithin fed to the birds. Then, it was tentatively concluded that the effect of the mutton fat on the energy and protein utilization was similar to tallow but resulted different tendency with lecithin.

• Journal of Animal Science and Technology
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• v.53 no.2
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• pp.155-160
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• 2011

Present experiment was carried out to determine maintenance energy requirements for growing Hanwoo steers. Six Hanwoo steers (BW = $180.6{\pm}3.1$ kg) were used in two 3 ${\times}$ 3 latin square design with three different energy intake levels; TDN 1.70 kg (Low), 2.05 kg (Medium), 2.80 kg (High), respectively, based on the Korean Feeding Standards. Each period lasted 18 days including a 14-day adaptation and a 4-day measuring period. The steers were in the head hood chamber system (one cattle per chamber) during each measuring time to measure heat and methane production for 1 day. Dry matter intake was 2,058, 3,256 and 3,881 g/day for Low, Medium and High TDN, respectively. Increase in energy intake did not affect digestibilities of dry matter, crude protein, crude fiber, crude fat, NDF, ADF and nitrogen-free extract. Gross energy intake averaged 180.21, 292.74 and 337.15 kcal/$BW^{0.75}$ for Low, Medium and High TDN, respectively. Energy loss was 28.7% in feces and 2.1% in urine of gross energy intake. Further, energy loss from methane produced during rumen fermentation was 6~8.3%, while body heat loss averaged 34~60%. Intercept of regression equation between ME intake and retained energy indicated that the energy requirement was 109.84 kcal ME/$BW^{0.75}$.

• Ocean and Polar Research
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• v.32 no.3
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• pp.269-289
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• 2010

In Summer 2008, a multidisciplinary survey was conducted onboard R/V Haeyang 2000 to understand plankton response to the three distinct physico-chemical settings that developed in the Ulleung Basin of the East Sea. Baseline settings of hydrographic conditions included the presence of the thin (<20 m) Tsushima Surface Water (TSW) on top of the Tsushima Middle Water (TMW). It extends from the Korea Strait to $37^{\circ}N$ along the $130^{\circ}E$ and then turns offshore and encompasses the relatively saline (T>$26^{\circ}C$, S>33.7) Ulleung Warm Eddy surface water centered at $36.5^{\circ}N$ and $131^{\circ}E$. A relatively colder and saline water mass appeared off the southeastern coast of Korea. It was accompanied by higher nutrient and chlorophyll-a concentrations, suggesting a coastal upwelling. Most of the offshore surface waters support low phytoplankton biomass (0.3 mg chl-a $m^{-3}$). A much denser phytoplankton biomass (1-2.3 mg $m^{-3}$) accumulated at the subsurface layer between 20-50 m depth. The subsurface chlorophyll-a maximum (SCM) layer was closely related to the nutricline, suggesting an active growth of phytoplankton at depth. The SCM developed at shallow depth (20-30 m) near the coast and deepened offshore (50-60 m). A fucoxanthin/zeaxanthin ratio was high in coastal waters while it was low in offshore waters, which indicated that diatoms dominate coastal waters while cyanobacteria dominate offshore waters. The community structure and biomass of phytoplanktonare closely related to nitrogen availability. Zooplankton biomass was higher in the coastal region than in the offshore region while species richness showed an opposite trend. Zooplankton community structure retained a coastal/offshore contrast. These suggest that summer hydrography is a stable structure, lasting long enough to allow a hydrography-specific plankton community to evolve.

• Journal of Animal Science and Technology
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• v.46 no.2
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• pp.193-200
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• 2004

This experiment was carried out to determine energy requirements for maintenance of Hanwoo steers. Nine Hanwoo steers weighing 376.6$\pm$12.5kg were used in this experiment and fed rice straw(44%) and concentrate (56%) at three different energy levels; 0.8 times maintenance(0.8M), 1.2 times(1.2M) and 1.6 times(1.6M), respectively. Dry matter intake was 48.5, 65.9 and 86.5g/$BW^{0.75}$ for 0.8M, 1.2M and 1.6M, respectively. Increase in energy intake with the increased DM intake did not affect digestibilities of dry matter, organic matter, crude protein, crude fiber, crude fat and nitrogen-free extract. Gross energy intake averaged 190.8, 255.8 and 340.9kcal/BW0.75 for 0.8M, 1.2M and 1.6M, respectively. Energy loss was 41% feces and 0.6${\sim}$1.5% urine of gross energy intake. Further, energy loss from methane produced during rumen fermentation was 5${\sim}$9%, while body heat loss averaged 40${\sim}$60%. Intercept of the regression equation between ME intake and retained energy indicated that energy requirement for maintenance was 124.3kcal $ME/BW^{0.75}$.