• Korean Journal of Environmental Biology
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• v.23 no.2 s.58
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• pp.135-140
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• 2005

In order to construct an artificial cultivation of Nostoc flagelliforme on solid medium, we attempted to assess the viability of approaches, which utilized either BG-11 agar or sand medium using both sterile and non-sterile algal segments. In the trial in which the BG -11 agar medium was inoculated with the non-sterile algal segments, the algae exhibited the rapid growth in the initial 4 days of cultivation. However, after 4 days of cultivation, the growth rate of the algae slowed, and the algal growth was completely stopped by 7 days of cultivation. When the BG -11 medium was inoculated with the sterile algal segments, the algae exhibited the rapid growth for a longer period of 8 days, reaching a length of 24.9 mm. The growth rate during this period was measured to be $24.5\%$. After the 8 days of cultivation, the algal growth rate began to slow and had almost stopped by the 13 days of cultivation. On the other hand, when the sterile algal segments were inoculated onto a sand plate, the algal segments decomposed, reaching total decomposition after 11 days of cultivation. By way of contrast, the desiccation treatment samples continued to grow for 14 days of cultivation. After 14 days of cultivation, the algae achieved a length of 26.1 mm, with a growth rate of $30.6\%$. Our results indicate that periodic desiccation may constitute an effective strategy for the prevention of algal decomposition.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.476-482
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• 2001

This experiment was conducted to evaluate the effect of slow-release fertilizer application on quality elevation of onion (Allium cepa L.) in southwestern sea. The slow-release fertilizers used were NIAST (National Institute of Agricultural Science and Technology) I, II, CDU (Crotonylidene Diurea), UF (Urea-Formaldehydes), and IBDU (Isobutylidene Diurea) 30, 50. Growth of the onion plant treated with slow-release fertilizer showed better than the control. However, a rate of infected plant to downy mildew was low as compared with control. Chlorophyll and total nitrogen contents were high in control, whereas firmness, soluble solid content, number and thickness of scaly leaves were high in slow-release fertilizer plot. In early maturing onion, total marketable bulb yield was higher in slow-release fertilizer plot than all other fertilizer treatments. Total marketable bulb yield in late maturing onion treated with slow-release fertilizer was slightly decreased. Decaying loss and the rate of sprouting during storage period decreased in slow-release fertilizer application. In summary, application of slow-release fertilizer increased marketable yield, storability after harvest and also reduced labor needs for top dressing.

• Journal of Animal Science and Technology
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• v.47 no.3
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• pp.439-446
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• 2005

This study was conducted to elucidate the influence of recombinant bovine somatotropin (rBST) on the plasma IGF-I profiles in deer stags. Slow release rBST (250mg each) preparations were injected subcutaneously during the antler's non-growing period and growing period. It was observed that significant increases in the plasma IGF-I concentrations were occurred right after injections of the rBST irrespective of antler's non-growing period or growing period. When the rBST preparations were injected two times with one week interval during the antler's non-growing period, the mean level of IGF-I was found to be 2,920.7ng I mL, indicating that the IGF-I concentration increased up to 8.4-folds compared with a control. After two weeks from second shot, however, the IGF-I levels decreased to the level of the control. Similar results were also obtained with both a Sika and a Red deer during the antler's growing period. Increases in the IGF-I level of up to 5.6-folds with the Sika deer and 4.3-folds with the Red deer were found. Based on the present study, it is likely that the rBST may be used as a possible candidate for an antler's growth stimulating agent.

• Journal of Korean Society of Forest Science
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• v.109 no.1
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• pp.62-71
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• 2020

With the aim of restoring slow-moving landslide areas, this study collected fundamental data from tree-ring analysis of curved trees in these areas. We collected both upper and lower stem disks to measure the azimuth angles of six trees with growth curvature caused by tension cracks. Additionally, we analyzed various factors in the slow moving landslide area. The geological strata and main constitutive rocks in the study area were anorthosite-formed in the Precambrian period; moreover, there were no intrusive rocks, other geological strata, geological folds, or faults. The talus with weathered rocks was distributed in the upper zone of the slow-moving landslide area. According to annual-ring analysis of curved trees and terrain analysis by satellite imagery, slow-moving landslide occurred from the top to the bottom end of the slope between 1999 and 2011. There was a significant relationship (P < 0.01) between the azimuth angle of cracks caused by the slow-moving landslide and the angle of the curved trees. These results suggest that the occurrence of slow-moving landslides could be confirmed through analysis of annual-rings of curved trees, underground water levels, and terrain (by satellite imagery).

• Journal of the East Asian Society of Dietary Life
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• v.15 no.4
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• pp.419-430
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• 2005

In this study, to prove the effect of soybeans's electron donating ability and its addition on eel gouem, storage and sensory characteristics were examined. During the storage period, pH values of all gouem samples were decreased with initial increase except the control. BSB $3\%$ sample had the lowest pH value and YSB $10\%$ sample was the highest 6.71 in pH value at first storage day. The electron donating ability of soybeans were increased with the amount of addition. The electron donating ability of SBSB 20g sample was the highest, which was 2 ${\~}$ 3 times higher than that of YSB sample. L values of all the gouem samples had a tendency to decrease according to the storage period and amount of addition. All samples' a values were increased throughout the storage period, while b values decreased except the control and GNG sample. TBA and VBN values of all the samples were up and down throughout the storage period SBSB $10\%$ sample had the lowest in TBA value. The electron donating ability of all soybean samples and TBA value of eel gouem samples showed a negative correlation. Total plate count of bacteria was increased rapidly for initial storage period, but all samples showed a tendency of slow growth after the 8th day of storage. During all storage days, SBSB, BSB samples had a similar tendency of low total plate count growth. GNG $10\%$ sample showed the lowest in total plate count of bacteria at sixteenth day of storage. Sensory scores of all samples decreased with storage. For all the items of the sensory evaluation, SBSB $5\%$ sample got the highest score among all eel gouem samples. GNGSB sample showed the lowest in TBA value and total plate count of bacteria. And in the sensory evaluation, GNGSB sample got the highest scores for several items.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.1 no.1
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• pp.31-43
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• 1968

1. Shell height frequencies of the fresh-water cockle, Corbicula elatior, sampled in the period of 1960 to 1963, are analyzed to assess the age composition and average growth pattern. Cumulative frequencies in a sample are traced on a probability scale, and the points of inflection on a probability graph are assumed to dissect age groups. 2. Seasonal growth of Corbicula elatior in the Naktong River ill as follows: Young cockles settle down on river-bed by June and grow rapidly during the summer season, reaching 14mm in shell height by October. From October to April the growth is very slow. The rapid growth in the second year starts around in May. 3. Survival rate per year for Corbicula elatior in the Naktong River is estimated to be $5\~10\%$ by age composition.

• The korean journal of orthodontics
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• v.10 no.1
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• pp.37-43
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• 1980

This study was undertaken to assess the effects of demethylchlortetracycline on bone growth of mandibular symphyseal region in rats. Demethylchlortetracycline at 30mg/kg body weight, respectively, were daily administered by mouth to the sewen female rats from 10th day of pregnancy to 13th day. Thirty six new-born rats from these experimental animals were used for histological examination at 1, 5, 10, 15, 20, 25 and 30 days. All these new-born rats were killed by an overdose of ether. Mandibular bodies were removed and fixed in $10\%$ neutral formalin,. Carney and aceton. Specimens were embedded, sectioned and stained with H-E, Van Gieson, PAS and prepared for alkaline phosphatase. The results were as follows; 1. Until erupting of incisors, hyaline cartilage was located in relatively large symphyseal space, but bone trabeculae of ossifying area at incisal side were arranged irregularly in experimental group. 2. During this period, PAS reaction was moderately positive, but alkaline phosphatase reaction was slightly positive. 3. By erupting or incisors, symphyseal space appeared narrower like control group, but alkaline phosphatase reaction tended to slow down. 4. By erupting of molars, symphyseal space appeared muck narrower, and cartilane plate was reduced and aealed off like control group. Alkaline phosphatase reaction tended to slow down severely.

• Journal of Applied Biological Chemistry
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• v.48 no.1
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• pp.11-15
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• 2005

Salinity of soils in greenhouse has been increased by massive application of fertilizers. Nitrogen fertilizer was most popular, and thus nitrate became the majority of soil salinity. Accumulation of nitrate led to deleterious effects on the growth and development of crops and vegetables. Microbial strains able to utilize nitrate and thus remove excess nitrate from farm land soils were isolated from 15 different soils of greenhouses and plastic film houses. Four strains able to grow in medium containing 50 mM $KNO_3$ were isolated, among which only E0461 showed high capacity of nitrate uptake. Nitrate uptake by E0461 was dependent on culture medium and was increased by addition of tryptone and peptone. Although E0461 was able to grow without tryptone and peptone, growth was slow, and no nitrate uptake was observed. Nitrate appeared to facilitate E0461 growth in the presence of tryptone and peptone. Through kinetic analysis, nitrate uptake was measured at various concentrations of nitrate, and half-life was calculated. Nitrate concentration decreased with increasing incubation period, and plot between half-lives and initial concentrations of nitrate fitted to single exponential function. These results suggest one major factor plays an important role in microbial nitrate uptake.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.1
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• pp.54-64
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• 1995

The effects of swirl on early flame development and late combustion characteristic were investigated using a high speed single-shot visualized 51 engine. LDV measurements were performed to get better understanding of the flow field in this combustion chamber. Spark plugs were located at half radius (R/2) and central location of bore. High speed schlieren photographs at 20,000 frames/sec were taken to visualize the detailed formation and development of the flame kernel with cylinder pressure measurements. This study showed that high swirl gave favorable effects on combustion-related performances in terms of the maximum cylinder pressure and flame growth rate regardless of spark position. However, at R/2 ignition the low swirl shown desirable effects at low engine speed gave worse performances as engine speed increased than without swirl. There were distinct signs of slow-down in flame growth during the period when the flame front expanded from 2.5mm in radius until it reached 5.0mm apparently due to the presence of ground electrode. There seemed to be heat transfer effect on the flame expansion speed which was evidenced in high swirl case by the slowdown of the late flame front presumably caused by relatively large heat loss from burned gas to wall compared with low- or no-swirl cases.

• Weed & Turfgrass Science
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• v.4 no.4
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• pp.383-389
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• 2015

The use of zoysiagrass (Zoysia japonica Steud.) in the transition zone is limited because of a lack of cold hardiness although zoysiagrass has many advantages compared to other warm-season and cool-season grasses. Late-fall N fertilization is often applied for darker green color of turfgrass in early spring and more extensive root growth without rapid top growth. The objective of the study was to evaluate the effects of late fall N application and turf cover for zoysiagrass spring green-up. Clear polyvinyl chloride (PVC) film was used for turf cover. The amount of N applied were 5 and $10g\;N\;m^{-2}$ for the low and high N rate treatments, respectively. Covered zoysiagrass had greater turfgrass color and quality in early spring than non-covered zoysiagrass. The high N rate had 0.6 to 2.3 greater turfgrass quality than the low N rate on 7 of 9 rating dates. Slow-release N as late fall fertilization is more effective for turfgrass color and quality than fast-release N in spring. Turf cover could reduce the period of yellow zoysiagrass, and the earlier time of spring green-up could be advanced by increasing turfgrass quality and growth of zoysiagrass.