• Weed & Turfgrass Science
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• v.4 no.1
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• pp.49-57
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• 2015

This research was initiated to analyze the periods of spring green-up and winter leaf discoloration of three ornamental grasses which have potential to be widely used with seed propagation. Two native grasses of Arundinella (Arundinella hirta var. ciliata Koidz), fountaingrass (Pennisetum alopecuroides (L.) Spreng), and switchgrass (Panicum virgatum L.) was tested. Spring green-up were evaluated after one year growth from seed propagation on April 1, 2009. Arundinella started with quick pick of spring green-up during $13^{th}$ to $20^{th}$ of May. Fountaingrass and switchgrass showed relatively slow picks of green-up during $20^{th}$ to $27^{th}$ of May. However, winter leaf discoloration started on swtichgrass and fountaingrass but Arundinella terminated relatively slowly. Swtichgrass showed the pick discoloration during $8^{th}$ to $15^{th}$ of October from the bottom to top parts of the plant. Fountaingrass showed the pick winter discoloration started from bottom to top parts during the $22^{nd}$ to $29^{th}$ of October. However, Arundinella showed relatively slow discoloration from upper to bottom parts during October $29^{th}$ to November $5^{th}$. Arundinella showed a relatively higher ornamental value with 125 days of the complete green period compared than fountaingrass and swtichgrass which maintained approximately 105 days of green period.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.4
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• pp.284-289
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• 1994

A nutrient solution culture experiment was conducted in the greenhouse of Suwon Campus, Kyung-Hee University from May 23 to July 11, 1994, to determine the effects of phosphorus application on seedling growth of Kwanganok and Hwengsungok cultivars of corn. Plants were harvested at weekly interval for seven weeks, at which time plant height, leaf area and dry matter yield of corn seedling were measured. The major results obtained are as follows. In without phosphorus pot, seedlings of Kwanganok and Hwengsungok cultivars have hardly been growing from planting to harvesting time. Plant height, leaf area and dry matter yield of both cultivars were increased more in the seedlings grown under complete treatment compared with the other phosphorus treatments. The total plant height, leaf area and dry matter yield during the whole period of Kwanganok and Hwengsungok cultivars were decreased in order of C>2P>3P>-P application pot. The crop growth rates of seedlings of both cultivars with in all treatments were slow until the 4th week after planting. Kwanganok with 2P and 3P treatment pot and C pot of Hwengsungok reached the maximum CGR at the 5th to 6th week after planting and showed declined CGR's thereafter, but Kwanganok C and Hwengsungok 2P treatment pots maintained a steady increase in CGR's until the end of the experiment period.

• 한국해양학회지
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• v.30 no.5
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• pp.403-412
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• 1995

The present study was performed to determine th growth and production of Mactra veneriformis on the Songdo tidal flat off Inchon. west coast of Korea. Monthly samples were collected from Marc 1989 to September 1990. The size distributions of shell length showed unimodal patterns from March to August 1989. The binodal pattern after September 1989 indicated a recruitment of young clams during this period. The density fluctuated irregularly, but showed a decreasing pattern over time on the whole. The density of the year class 1989 increased markedly after February 1990. The growth in shell length showed three phases during a year, a fast growth phase in spring, a slow growth phase in summer and autumn, and a lag phase in winter. The annual increment in shell length reduced with age. The flesh dry weight showed a peak in late spring just before the spawning period, and another peak in autumn. The length of annuli and the back-calculated flesh dry weight were used to describe the annual growth. The growth in shell length fitted to the von Bertalanffy model and the flesh dry weight to the Gompertz model. The absolute growth rate of the shell length reduced gradually with age. The year class 1985 had the highest L, and the yeat class 1986 the lowest L. The annual growth in weight showed a typical sigmoid curve. The growth rate was maximum at the age of 2 to 3. Year classes of 1984 and 1985 had higher values of W and higher absolute growth rates than those of 1986 and 1987. Maximum absolute growth rates of 1986 and 1987 year classes were recorded at younger ages than 1984 and 1985 year classes. The annual relative growth rates of length and weight decreased exponentially with age. Biomass in flesh dry weight increased till spring and thereafter decreased progressively. Maximum biomass was 134.6g m/SUP -2/ in August 1990. The biomass of 1989 yeat class occupied highest proportion in total biomass. Annual production in flesh dry weight from March 1989 to March 1990 was 67.9 g m/SUP -2/ year/SUP -1/. Cumulative production of 1989 year class was highest among all year classes, and that of year class 1984 was lowest. The production is high in spring and autumn, and very low in summer and winter.

• Journal of Animal Science and Technology
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• v.48 no.5
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• pp.663-670
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• 2006

The present study was performed to investigate the effect of plant type recombinant porcine somatotropin (pST) adminstration on growth performance and blood profile of finishing pigs. Forty-eight Landrace barrows weighing 78 kg were employed for six week growth trial. Twelve barrows were allocated into various rpST types ; the control (CONT), the 4:1 type rpST (TRT 1), the 1:1 type rpST (TRT 2); and the 4:1 type rpST group(TRT 3) respectively. CONT group were not planted rpST. TRT 1 group was treated with rpST once a week for 6 weeks. Each dose contained the rpST equivalent to 100mg from initial to two weeks and 125mg from three weeks to finial week. TRT 2 and TRT 3 groups were planted rpST four times contained the rpST equivalent to 100mg during trial period from initial to two weeks, and 125 mg from three weeks, to four weeks, respectively. All pigs were fed a commercial feed containing 0.9% lysine ad lib. Daily gain increased by 19.4% in TRT 1(p<0.05) compared to the CONT. rpST improved feed/gain by 13.4～28.9% in all treatment groups(p<0.05). Back fat thickness of the all rpST treated groups were 23.3～29.2% thinner than that of the CONT. These results indicated that the rpST stimulated growth performance in finishing pigs and plant type rpST could be used as a growth stimulant for finishing pigs.

• The Korean Journal of Malacology
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• v.17 no.1
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• pp.19-26
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• 2001

To study the growth of transplanted Pacific oysters, Crassostrea gigas, we sampled Korean and Japanese oysters attached in Chinhae Bay near Gaduk Island and in Seto inland sea in Japan, respectively, suspended in Pukman Bay. Water Temperature ranged from 11.2 to 27.8$^{\circ}C$ (mean 19.84 ${\pm}$ 5.47$^{\circ}C$) on the surface, and 11.1 to 23.6$^{\circ}C$ (mean 18.31 ${\pm}$ 4.18$^{\circ}C$) on the bottom. Salinity ranged from 31.45 to 34.57 (mean 33.10 ${\pm}$ 1.16) on the surface, and from 31.69 to 34.35 (mean 33.24 ${\pm}$ 1.06) on the bottom. salinity was the lowest in September and October, and the highest in December. Growth of oysters in shell height showed a significant difference after being suspended at the farm, reaching 70.3 ${\pm}$ 12.5 mm in the Korean oysters and 96.2 ${\pm}$ 14.6 mm in the Japanese oysters in December. While the Korean oysters showed relatively low growth rate and cessation of growth after sudden growth between June and July, the Japanese oysters showed continuous growth during the whole farming period, although stepwise growth was observed. It was not until September that meat weight showed a significant difference between the two. After September, there was a sudden increase in the Japanese oysters, reaching 7.5 ${\pm}$ 2.9 g in December, but growth of the Korean oysters showed slow growth rate during whole farming period, reaching 4.6 ${\pm}$ 1.9 g in December. here was an obvious decrease in the meat weight of Japanese oysters in December, which might be attributed to restriction of food. Condition factors rebounded in October in the Korean oysters and in September in the Japanese oysters, respectively, attaining 12.8 in the Korean oysters and 15.3 in the Japanese oysters at the end of investigation on December. Shell length-height regression equations were as follows: Korean oysters: S$\sub$h/=2.922S$\sub$t/,-4.8024 (r$^2$= 0.8541) Japanese oysters: S$\sub$t/=3.623S$\sub$h/,-5.1239 (r$^2$=0.7782) This showed the possibility of morphological transformation in the shell of the Korean oysters since shell height was longer than those reported by Bae et al. (1976) and Lee et al. (1992).

• The Korean Journal of Mycology
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• v.26 no.2 s.85
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• pp.187-193
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• 1998

The effects of medium, incubation temperature, incubation period, pH of medium and $CO_2$ ondition during mycelial growth were investigated to study the factors associated with the formation of oidia in Flammulina velutipes. Oidia formation was increased when mycelial growth was poor, while oidia formation was inhibited in optimum condition of mycelial growth. Mating type of oidia was investigated to examine the effect of oidia formation on dikaryotic strain. Di-mon matings between oidia strains and original dikaryotic strain were carried out. Monokaryotic strains derived from oidia showed only one genotype. Seventy percent among Dimon mating strains showed slow mycelial growth and low yield of fruit-body, but others showed similar or high mycelial growth and yields in comparision with original dikaryon strain. One strain from di-mon mating demonstrated some differences in isozyme band pattern.

• Korean Journal of Medicinal Crop Science
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• v.22 no.6
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• pp.423-428
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• 2014

This study was performed to identify optimal harvesting time of ginseng seeds and to examine the effect of $GA_3$ treatment for improvement of seed stratification rate. Ginseng seeds harvested from Land race, Chunpoong and Yunpoong cultivar in July 20 were tested for stratification rate. It was shown that stratification rates of land race, Yunpoong and Chunpoong cultivar were 94.1%, 93.1%, and 82.6%, respectively. Seeds of Chunpoong cultivar harvested 10-15 days later showed a comparable stratification rate to that of Land race, indicating that late harvest of Chunpoong seeds is beneficial for the increase of stratification rate. The higher stratification rate was found in mature seeds (92.3%) than immature seeds (37.8%), both of which were harvested in July 20. Stratification rate of mature seeds harvested in July 15 was 87.5%, demonstrating optimal harvesting time of ginseng seeds with higher stratification rate is after mid-July. An exponential growth of endosperms of ginseng seeds was observed from early June to mid-June and then slow growth was observed. There was no obvious growth of embryos from fertilization to mid-August. After the this time, embryos quickly grew until late October. Thus, appropriate stratification control is essential during the period (from early September to late October) in order to optimize embryo growth and development. While no increase of stratification rate was observed in seeds treated with 50 ppm of $GA_3$, significant increases were observed in seeds treated with 100 ppm of $GA_3$. At this concentration of $GA_3$, the stratification rate of Land race, Chunpoong and Yunpoong cultivar was 95.0%, 95.3%, and 96.5%, respectively.

• Journal of the korean academy of Pediatric Dentistry
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• v.25 no.2
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• pp.335-351
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• 1998

Salivary proteins which are produced in the saliary acinar cells have been known to be involved in the Calcium and phosphate metabolism. The acquired pellicle resulting from such metabolism is considered as a secondary defence membrane against tooth caries. In this respect, some proteins included in saliva probably play an important role in the prevention of demineralization in enamel. On the other hand, fluoride has long been known to prevent the demineralization of enamel by the inhibition of the growth of Streptococcus mutans(S. mutans) and by the chemical reaction with calcium and phosphate, Therefore, I have examined the roles of amylase and albumin in the demineralization of enamel and compared these preteins with fluoride in terms of anticariogenic effect. 1. The demineralization caused by S. mutans occurred slowly and progressively for the first 60 min, then the rate of demineralization was accelerated afterwards. 2. pH decreased continuously during the entire period of each experiment. 3. The demineralization was significantly inhibited by the preteatment of amylase and fluoride but albumin had little effect on it. 4. An addition of 0.1 mM lactic acid (final concentration 0.1 ${\mu}M$) caused a rapid increase in calcium concentration reaching a maximum within 10 min. 5. pH decreased rapidly by the addition of 0.1 mM lactic acid and reached a minimum within a few seconds followed by an increase in pH. pH reaced a plateu with 10 min. 6. Fluoride, amylase and albumin played little role in the 0.1 mM lactic acid-induced demineralization. 7. A slow infusion of 0.1 M lactic acid at a rate of 5 ${\mu}l/min$ caused a slower increase in calcium concentration compared with the bolus addition of lactic acid. 8. Fluoride had an inhibitory effect on the calcium release caused by slow infusion of lactic acid while amylase and albumin had no effect on it. These results suggest that fluoride inhibits demineralization by protecting the HA from the acid attack whereas amylase has a direct effect on S. mutans to prevent demineralization.

• Korean journal of food and cookery science
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• v.11 no.4
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• pp.379-385
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• 1995

The effect of low concentrations of ethanol (3-7％, v/v) in tryptic soy broth (TSB) as an antibacterial agent against Listeria monocytogenes was tested at -20, 5, 35, 45, 50 and 55$^{\circ}C$. Increasing concentrations of ethanol progressively inhibited initial growth of L. monocytogenes at 35$^{\circ}C$. Growth occured at 5％ ethanol, but only after a prolonged lag period. The number of viable cells of L. monocytogenes declined during incubation at 7％ ethanol. TSB containing 3-7％ ethanol was inoculated with 10$\^$5/-10$\^$6/ cells/$m\ell$ or L. monocytogenes and incubated at low temperatures (5$^{\circ}C$, -20$^{\circ}C$). In the presence of 3％ of ethanol at 5 or -20$^{\circ}C$, bacterial growth was inhibited more than 90％ of control cells. TSB containing 3-7％ ethanol was inoculated with 10$\^$6/-10$\^$7/ cells/$m\ell$ of L. monocytogenes and incubated at high temperatures (45$^{\circ}C$, 50$^{\circ}C$, 55$^{\circ}C$). Decrease in viability of the cells incubated at 45 or 50$^{\circ}C$ was slow and the survival of L. monocytogenes was not affected so much in the presence of 3％ of ethanol. The viability of L. monocytogenes was decreased with increasing concentration of ethanol and temperature. Decimal reduction times (D-values) based on tryptic soy agar plates at 55$^{\circ}C$ were 20.1, 12.6, 7.4 and 4.2 min in 0, 3, 5 and 7％ ethanol, respectively.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.2
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• pp.286-290
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• 2003

The fibroma is the most common benign soft-tissue tumor found in the oral cavity and most commonly occurrs in sites predisposed to irritation or trauma. Treatment is conservative surgical excision. Seldom does the lesion recur. A 14-year old girl was referred to the Department of Pediatric Dentistry for evaluation and management of a mass on the palate. The patient's parents reported the slow growth of this soft tissue lesion over a 6-month period. A history of trauma or irritable habits was denied. Clinical examination revealed an asymptomatic, soft, pedunculated elevation of mucosa, measuring 3cm in diameter. Excisional biopsy of the lesion supported a diagnosis of fibroma. There have been no signs of recurrence during follow up of 4 years after surgical intervention. The clinical picture, pathology and management of the case are described, and the differential diagnosis and treatment are discussed.