• Korean Journal of Plant Tissue Culture
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• v.22 no.5
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• pp.299-306
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• 1995

The objective of this study is to establish an efficient celll culture system for somatic embryogenesis in Ostericum koreanum and Angelica purpuraefolia. The highest frequency of embryogenic callus on immature seeds of O. konanum and A, purpuraefolia. was obtained when seeds were cultured on MS medium containing 0.1 mg/L 2,4-D and 0.1 mg/L BA. However somatic embryos were formed directly from the edge of cotyledon and hypocotyl of plant which regenerated on medium supplemented with 0.1-3.0 mg/L NAA. Immature seed explane cultured at 25$\pm$2$^{\circ}C$ after 10 days treatment at 5$^{\circ}C$ produced embryogenic callus and somatic embryos, and these differentiated into whole plane. Addition of glutamine and coconut milk to media did not enhance the frequency of somatic embryogenesis in immature seed cultures of A. purpuraefolia. However in immature seed culture of O. koreanum, the frequency of somatic embryogenesis were increased on media supplemented with glutamine and 10% coconut milk. Especially addition of glutamine to the medium substituted effect of NH$_4$N0$_3$ in constast to coconut milk. The highest frequency of conversion somatic embryos into plantlet was 89.1% on MS basal medium Embryogenic calli were grown vigorously when maintained on medium with 0.01 mg/L 2,4-D and 0.01 mg/L BA.

• Applied Biological Chemistry
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• v.38 no.3
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• pp.278-282
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• 1995

The effect of Schizandrae fructus extract on the physiological properties of Saccharomyces cerevisiae was investigated. S. cerevisiae was inoculated into glucose broth, added with Schizandrae fructus extract, 0, 0.01, 0.1, 0.5 and 1%(w/v), respectively. And a 96 hours incubation was followed to investigate the changes in the growth, alcohol production, alcohol dehydrogenase and pyruvate decarboxylase activities of S. cerevisiae. The growth of S. cerevisiae was more pronounced in the broth containing 0.1 and 0.OlfS Schizandrae fructus extract than in the control. The growth was, however, inhibited in the broth containing 0.5 and 1% of the extract. The content of alcohol produced by S. cerevisiae also showed very similiar results with those of the yeast growth by addition of Schizandrae fructus extract. Alcohol dehydrogenase activities of S. cerevisiae cultured in broth treated with the extract of 0.1% and 0.01% increased by 25% and 18% than those in control group. Pyruvate decarboxylase activities in 0.1% and 0.01% treatments increased to 1.32 and 1.26 times. The activities in 0.5% and 1% treatments, however, decreased by 30% and 44%.

• Proceedings of the IEEK Conference
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• 2000.09a
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• pp.55-58
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• 2000

본 논문에서는 제한된 통신 채널의 대역에서 주파수 효율이 높은 OFDM 시스템을 위한 반송파 주파수 동기 알고리즘을 제안한다. OFDM 시스템에서의 반송파 주파수 옵셋은 부반송파 간격의 정수배와 소수배로 나누어진다 소수배 주파수 옵셋이 ± 0.5 근처의 값을 가질 경우에는 정확한 정수배 주파수 옵셋 추정이 어렵고 반송파 동기 PLL이 소수배 주파수 옵셋을 추적하는데 많은 시간이 소요된다. 제안한 알고리즘은 정수배 주파수 옵셋을 제거하기 위해 2개의 심볼 만을 이용하고 다중경로 패널에서도 정확한 정수배 주파수 옵셋의 추정이 가능하다 또한, 소수배 주파수 옵셋이 ± 0.5 근처의 값을 가질 경우 적은 계산량으로 주파수 옵셋을 ± 0.1 이내로 보상할 수 있다.

• Korean Journal of Animal Reproduction
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• v.23 no.1
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• pp.75-84
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• 1999

This study assessed development in vitro of pronuclear(PN) stage embryos cryopreserved by the method of either vitrification or slow freezing, by using of different cryoprotectants, and equilibration and cooling rate, in rabbit. Ethyleneglycol- ficoll- sucrose(EFS) or ethyleneglycol- polyvinylpyrrolidone - galactose- (EPG-I) for vitrification, and EPG- II for slow freezing as cryoprotectant were used. The pronuclear embryos were exposed to EFS for 0 to 5 min and diluted with D-PBS and/or pre-dilution with 0.5 M sucrose. To examine the viability of frozen-thawed embryos, PN embryos were co-cultured with bovine oviductal epitherial cell(BOEC) for 5 days to hatching blastocyst stage in 39 $^{\circ}C$ 5% $CO_2$incubator. The results obtained were as follows: The dilution with 0.5 M sucrose and D-PBS after the exposure to EFS for 1.0 min resulted in no significant(P＜0.05) decrease in the development of PN embryos to hatching blastocyst(72.0%), compared with controls. The development of PN embryos cryopreserved to hatching blastocyst was not significantly (P＜0.05) different between EFS for 1.0 min(72.0%), EPG-I for 1.0 min(72.0%) and EPG-II for 30 min(66. 7%). The post-thaw development of PN embryos to hatching blastocyst was similarly very low as 6.1% and 11.5% in vitrification with EFS and slow freezing with EPG-II, respectively. The incidence of post-thaw zona-crack in PN embryos cryopreserved by slow freezing with plunging to liquid nitrogen at －35$^{\circ}C$ was signicantly(P＜0.05) higher(25.0%), compared with －85$^{\circ}C$ (1.9%). These results indicated that the rabbit PN embryos could be cryopreserved with either vitrification or slow freezing procedure, and frozen PN embryos could be successfully developed in vitro to haching blastocyst. but the post-thaw development of cryopreserved PN embryos was still very low under the present conditions.

• Radiation Oncology Journal
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• v.18 no.2
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• pp.120-126
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• 2000

Purpose : Tumor hypoxia can be overcome with hypoxic cytotoxin. In mouse tumor, tirapazamine's efficacy of the potentiating radiation effect was tested by the tumor oxygenation status combined with hype facti on ated rad iotherapy .:The control and hypoxic mouse tumors we established by inoculation of RIF-1 tumor cells into the normal or previously irradiated back and thigh of C3H mice. When the tumors reached a proper size, both the control and hypoxic tumors were given hypefractionated treatments (8fractions/4 days) with saline (0.02 ml/g), tirapazamin (0.08 mM/0.02 ml/kg), irradiation (2.5 Gy), irradiation combined with tirapazamine given 30 minutes prior to each irradiation. The response was evaluated by the growth delay assay by measuring tumor size from day 0 (12 hrs prior to the first fractionation) to the day when the volume had 4-fold increase or cross sectional area had 2-fold increase. Results : Overall growth pattern showed that tirapazamine Potentiated radiation effect in back and thigh tumors grew in the normal and preirradiated tumor bed. With growth delay assay using reference point of initial tumor volume or cross sectional area, tirapazamine potentiated radiation effect 1.9 times for the control and 2.4 times for the hypoxic tumors in back, and 1.85 times for the control and 1.6 times for the hypoxic tumors. With reference of 4-fold increase of the initial volume or 2-fold increase of the cross sectional area, tirapazamine potentiated radiation effect 1.48 times for the control and 2.02 times for the hypxic tumors in back, and 1.85 times for the control and 1.6 times for the hypoxic tumors. Conclusions : Present result indicated that radiation response of hypoxic tumors was potentiated by tirapazamine in the back or thigh tumors grew in the control or preirradiated tumor bed, and potentiation of the hypoxic tumors was eDual to or greater than that of the control tumors in the back or thigh.

• Korean Journal of Agricultural Science
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• v.22 no.1
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• pp.62-68
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• 1995

This study was carried out to examine splitting, developmental capacity and rapid freezing of blastomeres separated from 2-, 4-, 8-cell and morula from porcine embryos. The results obtained in this study were summerized as follows : 1. The successful splitting rate by pronase was 85.7% in 2-cell embryos(average splitting rate, 68.0%), and by manipulator was 76.6% and 74.3% in 2- and 4-cell embryos. 2. The developmental capacity rates of splitted embryos by the pronase treatment were 24.1%, 20.4%. 25.5% and 26.6% in 2-, 4-, 8-cell and morula, and by manipulator were 36.4%, 39.5%, 36.1% and 41.9%, respectively. 3. The successful results of in vitro culture after frozen-thawed of splitted embryos were 16.1%(glycerol) in 2-cell, 16.7%(DMSO) in 4-cell and 27.6%(ethyleneglycol) in morula, respectively.

• Korean journal of applied entomology
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• v.33 no.3
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• pp.166-172
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• 1994

This study was conducted to investigate the resistance development and cross-res~stance of house fly (Musco dornestica L.) selected with chlorpyrifos, dichlorvos and permethrin for 11 generations to various p u p s of insectiodes. The resistance ratio (RR) of the chlorpyrifos-selected (Q), the d~chlorvos- selected (&) a d the permethrin-selected (R,) stmlns were 42 0. 38 and 187 tlrnes in female. and 42.0, 4 1 and 16.4 time; in male from the susceptible strain, respectively. The Rc strain showed highest cross-resistance to permethlin among the insectic~des tested: RR=7.5 and 9.6 tunes in female and male, respectively, whereas negatively correlated cross-resistance to propoxur was observed. High cross-res~atance to chlorpyrifos were produced for female (RR= 13.3) and male (RR=15.9) of Rd strain, and female (RR=8.7) and male (RR= 9 7) of R, strain. respectively

• Journal of Dairy Science and Biotechnology
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• v.35 no.4
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• pp.244-248
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• 2017

The effects of ultrasonic (1.2~1.7 kJ/g TS) pretreatment on the solubilization of dairy and livestock sludge were separately evaluated to investigate the possibility of recycling dairy sludge as a potential source of organic carbon. Compared to other industrial wastewater and sewage sludge, dairy sludge has higher organic matter content and no toxic materials. The solubilization rates of dairy and livestock sludge, at a specific energy input of 1.7 kJ/g TS, were 14.5% and 10.6%, respectively. After the 90-minute ultrasonic treatment, the soluble COD (chemical oxygen demand) increased about 7.1 times that of the initial SCOD, at an increase rate of $0.022m^{-1}$. In comparison, the increase in soluble nitrogen, which was ~3.4 times that of the initial soluble nitrogen concentration, was much smaller than the increase in SCOD; thus, the C/N ratio increased from 4.0 to 8.7.

• Journal of dental hygiene science
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• v.12 no.2
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• pp.93-102
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• 2012

The purpose of this study was to evaluate the effectiveness of oral health care including some of dental caries activity test on dental clinics of regular visiting on primary school children. The dental surveys and initial caries control and some of dental caries activity test (Alban's, Lactobacillius, S'mutans, un-stimulation saliva test)were performed by trained dental hygienists with dentist from on 6 to 13 years old patients of S dental hospital in Gwangju Metropolitan Cities. The sample size of 39 children (18 in oral health care group, 21 in control group ) and accepted to their parents. The results of caries activity test score(Alban's and Lactobacillius test)were reduced 1.4 to 1.6 times in oral health care group(OHCG). Oral Hygiene Simplified Index of OHCG was reduced 1.6 times during six months and 1 year. DMFT index of OHCG was reduced 1.4 times more than Control Group(CG) after 1 year. DT index of OHCG was reduced 12 times more than Control Group(CG) after 1 year. Dental health capacity of the first perment molar of OHCG was reduced 1.02 times more than CG after 1 year. From the above results, long life related incremental oral health care system has reinforced to primary school children in dental clinic with oral health professional teams.

• Current Research on Agriculture and Life Sciences
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• v.7
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• pp.83-97
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• 1989

This study was carried out to obtain basic information necessary for aggregation and in-vitro culture of mouse embryos by treating phytohemagglutinin-p (PHA-P). The 4-, 8-cell and morula embryos were obtained from female mice of albino BALE/C, CBA and C57BL strains, those were injected 5 i.u pregenant mare serum gonadotrophin and 5 i.u human chorionic gonadotrophin to superovulation. The zona pellucidia was removed by placing the embryos in Acidic Tyrode solution containing 1.0% protease or/and 5 ug/ml PHA-P. The pairs of zona free embryos were subjected to aggregation by glassneedle in BMOC-3 containing 5 ug/ml PHA-P. The aggregation embryos were cultured in Brinster's mouse ova culture-3(BMOC-3) medium under the gas phase of 5% $CO_2$ in air $37^{\circ}C$ for 13 to 50 hours. The results obtained in this study are summarised as follows : 1. When 4-, 8-cell and morula embryos were zona-freed in acidic Tyrode solution containing 1.0% protease or/and 5 ug/ml PHA-P, and cultured in vitro to blastocysts, the 4- and 8-cell embryos showed slightly less development rates than the morula one did, and solution of 5 ug/ml PHA-P brought some higher development rate than negative control. 2. As 2, 5 or 10 ug/ml PHA-P was added to the solution to aggregate 4-, 8-cell or morula embryos, 2 ug/ml solution represented slightly lower aggregation rate than the higher levels solutions, and 4- and 8-cell embryos showed higher rates than morula one did (P<.05). 3. In respect to the development rates of aggregated embryos to morula no significant difference was found among PHA-P levels and between 4-and 8-cell embryos. With respect to those of aggregated embryos to blastocysts the different levels of PHA-P showed similar results, however, the 4- and 8-cell embryos represented higher rates than the morula one did (P<.05). 4. The mean time necessary for development of aggregated 4-, 8-cell and morula embryos to blastocysts were 38.5-40, 26-27 and 19-20hrs. Respectively in solution for aggregation. 5. The aggregation rates of embryos were 34-94%, when treated protease or/and PHA-P. Supplementation of 5 ug/ml PHA-P to the solution for aggregation showed a trend demonstrating higher aggregation rate compared to negative control, although no significance was found. However, 4- and 8-cell embryos represented significantly higher aggregation rates than the morula one did (P<.05). 6. The development rates of 4- and 8-cell embryos to morula were 52.7-84.7 and 73.8-87.2%, respectively, showing no significant difference between two cell stages. However, the aggregation rates of embryos treated with solution containing PHA-P were higher than negative control (P<.05). 7. The development rates of 4- and 8-cell and morula embryos to blastocysts were 41.7-77.7 78.7-83.0 and 0-19.2%, respectively. The rates of 4-cell embryos treated with PHA-P were significant higher than the negative control (P<.05). The 8-cell and morula embryos also showed more rates when treated PHA-P.