• 대한수의학회지
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• 제32권4호
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• pp.663-669
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• 1992

This experiment was carried out to find out the best condition for the parthenogenetic activation of mouse eggs by treating ethanol and hyaluronidase. For the parthenogenetic activation of eggs with ethanol, cumulus cell enclosed or denuded eggs were treated with 7% ethanol in D-PBS for 5, 7 or 9 minutes. For the activation of eggs with hyaluronidase, the eggs with cumulus masses were released into D-PBS with 100 unit hyaluronidase and treated for 10, 12 or 13 minutes. All of the treated eggs were incubated in BMOC-3 solution for 5 hours at $37^{\circ}C$ at an atmosphere of 5% $CO_2$ in air. The types of parthenogenetic eggs were morphologically classified into haploid, diploid, immediate cleavage eggs under an inverted microscope. The results obtained in this experiment were summarized as follows ; 1. High activation rate(99%) had been achieved by treating the eggs with 7% ethanol for 7 minutes. 2. With 100 IU hyaluronidase, high activation rate (94%) had been achieved by treating for 12 minutes. 3. The most frequent type of parthenogenetic eggs activated with ethanol or hyaluronidase was haploid (p<0.05). 4. The eggs collected from 18 to 22 hours post HCG injection showed higher activation rate than the eggs collected at 16 hours post HCG injection. 5. No significant difference (p>0.05) in activation rate was shown in strain of mouse and in presence of cumulus cells.

• 대한수의학회지
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• 제37권3호
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• pp.639-645
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• 1997

The objectives of the present study were improvements in the efficiency of developmental rates to morula and blastocyst stages to produce a large number of genetically identical nuclear transplanted embryos. The oocytes collected from slaughterhouse ovaries were matured 24h in TCM199+10% FBS and exposed to $39^{\circ}C$ or room temperature to allow cytoplasmic maturation and gain activation competence. Donor embryos were treated for 12h with $10{\mu}g/ml$ nocodazole or $0.05{\mu}g/ml$ demicolcine to synchronize the cell cycle stage at 26h after the onset of culture. The blastomeres and recipient oocytes were fused by electrofusion. The cloned embryos were then cultured in various conditions to allow further development. In the treatment of oocyte activation and cell cycle regulation of donor nuclei, the room temperature exposure and nocodazole treatment group had significant effect on the developmental rates to morula/blastocyst(21.7% vs 12.1~16.7%), but had no significant effect on the fusion rates between donor blastomeres and recipient oocytes. The developmental rates of bovine nuclear transplanted embryos appeared to be higher significantly in mTALP medium under 5% $O_2$ condition and in TCM199 with bovine oviduct epithelial cell under 20% $O_2$ condition(22.2%) than other groups. In embryo transfer of nuclear transplanted embryos, there were no significant differences in calving rates between the use of excellent and good grade donor embryos.

• 한국수소및신에너지학회논문집
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• 제9권3호
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• pp.127-133
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• 1998

각각 다른 기판온도에서 진공 증착법으로 제작된 Pd 박막들의(두께 ) 수소 흡수-방출 동역학을 실험하였다. 상, 온도영역에서 수소기체를 흡수-방출 시키면서 정방향과 역방향 활성화에너지를 구하고 반응엔탈피를 구하였다. 기판의 온도가 상온인 시료는 정반응 활성화에너지가 kcal/mol H이고 역방향은 kcal/mol H 반응엔탈피는 -2kcal/mol H였다. 기판의 온도가 인 시료는 정방향 활성화에너지 kcal/mol H 이고 역방향 활성화에너지 kcal/mol H였다. 기판의 온도가 상온인 시료의 구조적 치밀성, 온도변화에 따른 비저항 값의 변화율 등을 측정해 보았을 때 기판의 온도가 상온인 시료에 비하여 더 안정된 상태였지만 활성화 에너지의 오차값이 크게 얻어졌다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제25권4호
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• pp.77-86
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• 2020

Persulfate-based advanced oxidation processes (AOPs) can oxidize various organic pollutants. In this study, persulfate/Fe(II) system was utilized in phenol removal, and the effect of various organic and inorganic chelators on Fe(II)-medicated persulfate activation was investigated. The feasibility of persulfate/Fe(II)/chelator in cleanup of phenol-contaminated sediment was confirmed through toxicity assessment. In persulfate/Fe(II) conditions, the rate and extent of phenol removal increased in proportion to persulfate concentration. In chelator injection condition, the rate of phenol removal was inversely proportional to chelator concentration when it was injected above optimum ratio. Thiosulfate showed greater chelation tendency with persulfate than citrate and interfered with persulfate access to Fe(II), making the latter a more suitable chelator for enhancing persulfate activation. In contaminated clay sediment condition, 100% phenol removal was obtained within an hour without chelator, with the removal rate increased up to four times as compared to the rate with chelator addition. A clay sediment toxicity assessment at persulfate:Fe(II):phenol 20:10:1 ratio indicated 71.3% toxicity reduction with 100% phenol removal efficiency. Therefore, persulfate/Fe(II) system demonstrated its potential utility in toxicity reduction and cleanup of organic contaminants in sediments.

• 대한의생명과학회지
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• 제15권2호
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• pp.153-160
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• 2009

Photodynamic therapy(PDT) is a treatment utilizing the generation of singlet oxygen and other reactive oxygen species(ROS), which selectively accumulate in target cells. The aim of present work is to investigate the photodynamic therapy mechanism of 9-HpbD-a-mediated PDT in HeLa cell lines. We studied the general reactive oxygen species(G-ROS) activation after 9-HpbD-a PDT using fluorescence stain with $H_2DCF-DA$. G-ROS activation observed after 9-HpbD-a PDT and higher activation condition was 1 hour after PDT at 0.5 ${\mu}g/ml$ 9-HpbD-a concentration. Sodium azide and reduced glutathione(the singlet oxygen quencher) could protect HeLa cells from cell death induced by 9-HpbD-a PDT. But D-mannitol(the hydroxyl radical scavenger) could not protect cell death. Singlet oxygen played a decisive role in 9-HpbD-a PDT induced HeLa cell death. Type II reaction was the main type of ROS formation at 9-HpbD-a PDT.

• 한국수소및신에너지학회논문집
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• 제20권4호
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• pp.283-290
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• 2009

This study focuses on the performance characteristics of polymer electrolyte membrane fuel cell (PEMFC) using the AC impedance technique. The experiment was carried out to investigate the optimal operating conditions of PEMFC such as cell temperature, flow rate, humidified temperature and back-pressure. The fuel cell performance was analyzed by DC electronic-loader with constant voltage mode and expressed by voltage-current density. Additionally, AC impedance was measured to analysis of ohmic and activation loss and expressed by Nyquist plot. The results showed that the cell performance increased with increase of cell temperature, air flow rate, humidified temperature and backpressure. Also, the activation loss decreased as the increase of cell temperature, air flow rate, humidified temperature and backpressure.

• 가정과삶의질연구
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• 제30권2호
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• pp.173-187
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• 2012

This qualitative case study focused on the activation plan of flexible work arrangements. We selected eight workers from a foreign affiliated firm that has various flexible work arrangements for in-depth interview and focus group interview. The workers were categorized into two groups; those who have experiences with flexible working and those who have needs for flexible working. We analyzed their condition of work-family life and experiences with flexible working. Through the focus group interview, we can find out the needs and suggestions about activation plans of flexible work arrangements.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2009년 춘계학술발표대회 논문집
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• pp.268-272
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• 2009

The program of public facilities are essential of resident life, and these programs affect quality of life and community activation. The purpose of this study is to analyze the present condition of the program of public facilities and residents' need of program in Yanglim-Dong, Gwangju. In this study, Field survey and questionnaire survey are used for data collection. The results of this study are showed as follows: First, most of the public facilities' programs are composed of educational and welfare program and program for teenager, young people and middle-age. Second, most of the residents prefer to program for culture and sport. Third, most of the residents want to join in one or two every weeks and the time zone of p.m..

• 한국재료학회:학술대회논문집
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• 한국재료학회 2010년도 춘계학술발표대회
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• pp.56.1-56.1
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• 2010

A novel electrochemical potentiostatic method has been examined in order to enhance the hole concentration of p-type GaN thin films using KOH and HCl electrolyte. The hole concentration was increased more than 2 times by the electric voltge apply with the mobility of $10{\sim}12cm^2/V.s$. At optimum condition of 3V apply, hole concentration was enhanced more than reference sample from $1.7{\times}10^{-17}cm^{-3}$ to $4.1{\times}10^{-17}cm^{-3}$. Application of this activation method to blue-LED fabrication improved optical output from 18.4mW to 20.6mW, that is ~12% increase. SIMS analysis indicates that nearly 70% of hydrogen atoms could be removed by this method.

• Biomolecules & Therapeutics
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• 제16권1호
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• pp.1-8
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• 2008

Mitochondria are important sensor of apoptosis. $H_2O_2-induced$ cell death rate was enhanced by serum deprivation. In this study, we investigated whether serum deprivation using 0.5 or 3 % FBS induces apoptotic cell death through mitochondrial enzyme activation as compared to 10 % FBS. Apoptotic cell death was observed by chromosome condensation and the increase of sub-G0/G1 population. Serum deprivation reduced cell growth rate, which was confirmed by the decrease of S-phase population in cell cycle. Serum deprivation significantly increased caspase-9 activity and cytochrome c release from mitochondria into cytosol. Serum deprivation-induced mitochondrial changes were also indicated by the increase of ROS production and the activation of mitochondrial enzyme, succinate dehydrogenase. Mitochondrial enzyme activity increased by serum deprivation was reduced by the treatment with rotenone, mitochondrial electron transport inhibitor. In conclusion, serum deprivation induced mitochondrial apoptotic cell death through the elevation of mitochondrial changes such as ROS production, cytochrome c release and caspase-9 activation. It suggests that drug sensitivity could be enhanced by the increase of mitochondrial enzyme activity in serum-deprived condition.