• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.184-184
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• 1999

반도체소자의 고집적, 미세화에 따라 MOSFET 소자에서의 고농도, 미세접합이 요구되고 있다. 이러한 고농도, 미세접합을 형성하기 위하여 기존의 저에너지 이온주입법을 대체 또는 병행할 목적으로 플라즈마 이온주입방법이 활발히 연구되고 있다. 본 연구에서는 플라즈마 이온주입방법을 이용하여 (100) 실리콘 기판에 보론을 주입후 열처리하여 형성된 p+층의 도펀트의 활성화와 이온주입으로 인한 실리콘 기판의 손상을 고찰하였다. 본 실험에서 (100)실리콘 기판에 도핑할 소스 가스로 BF3을 주입하고, D.C. pulse 플라즈마 도핑시스템을 사용하여 플라즈마 내의 보론이온을 웨이퍼 홀더에 -1~-5kV의 인가된 음전압에 의해 가속시키어 실리콘 웨이퍼에 주입하였다. 주입에너지 -1kV, -3kV, -5kV와 1$\times$1015, 3$\times$1515의 dose로 주입된 실리콘 기판을 급속가열방식(RTP)을 사용하여 $600^{\circ}C$~110$0^{\circ}C$의 온도구간에서 10초와 30초로 열처리하여 도펀트의 활성화와 미세접합을 형성한 후 SIMS, four-point probe, Hall 측정, 그리고 FT-IR을 이용하여 플라즈마 이온주입된 도펀트의 거동과 활성화율을 관찰하였고 FT-IR과 TEM의 분석을 통하여 이온주입으로 인한 실리콘 기판의 손상을 고찰하였다. SIMS, four-point probe, Hall 측정, 그리고 FT-IR의 분석으로 열처리 온도의 증가에 따라 도펀트의 활성화율이 증가하였고, 이온주입 에너지와 dose 그리고 열처리 시간의 증가에 따라서 주입된 도펀트의 활성화는 증가하였다. 그리고 주입에너지와 dose 그리고 열처리 시간의 증가에 따라서 주입된 도펀트의 활성화는 증가하였다. 그리고 주입에너지와 dose를 증가시키면 접합깊이가 증가함을 관찰하였다. 이온주입으로 인한 기판손상의 분석을 광학적 방법인 FT-IR과 미세구조를 분석할 수 있는 TEM을 이용하여 분석하였다. 이온주입으로 인한 dislocation이나 EOR(End Of Range)과 같은 extended defect가 없었고, 이온주입으로 인한 비정질층도 없는 p+층을 얻을수 있었다.

• Korean Chemical Engineering Research
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• v.53 no.4
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• pp.472-477
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• 2015

This study presents modified microfluidic picoinjector combined Faraday moat with silver nanoparticle electrode to increase electrical efficiency and fabrication yield. We perform simple dropping procedure of silver nanoparticles near the picoinjection channel, which solve complicate fabrication process of electrode deposition onto the microfluidic picoinjector. Based on this approach, the microfluidic picoinjector can be reliably operated at 180 V while conventional Faraday moat usually have performed above 260 V. Thus, we can reduce the operation voltage and increase safety. Furthermore, the microfluidic picoinjector is able to precisely control injection volume from 7.5 pL to 27.5 pL. We believe that the microfluidic picoinjector will be useful platform for microchemical reaction, biological assay, drug screening, cell culture device, and toxicology.

• Journal of Embryo Transfer
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• v.16 no.2
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• pp.73-78
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• 2001

This study was carried out to investigated developmental ability of IVM/IVF derived hanwoo embryos after DNA microinjection. Microinjected hanwoo embryos were cultured fur 7 days. The cleavage rates of DNA injected embrys(36.3%) was significantly lower than those of non-injected embryos(67.4%; p<0.05). The percentage of injected embryos reaching to the morulae and blastocyst was significantly lower than those of non-injected embryos(p<0.05). When injected embryo were cultured contaning L-ascorbic acid and $\alpha$-tocopherol for 168 hrs, the morulae and blastocyst rates were significantly higher than control(p<0.05). These results suggested that the addition of L-ascorbic acid and $\alpha$-tocopherol can enhanced development to the morulae and blastocyst of microinjected embryos and improved culture condition increased the transgenic hanwoo embryos.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.2
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• pp.193-201
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• 1999

In this study we determined fertilization processes and developmental ability of porcine oocytes following injection of round spermatid in the presence of artificial activation. Electrical stimulation at 3 h before spermatid injection significantly increased the incidence of normal fertilization as compared to those following injection without stimulation or with stimulation immediately after injection. The incidences of two pronuclear formation and apposition were not different in oocytes between following intracytoplasmic spermatid and spermatid nucleus injection. Indirect immunocytochemistry and laser scanning confocal microscopy study revealed that micro tubules were organized from the oocyte cortex following round spermatid injection, and this seemed to move both male and female pronuclei into the oocyte center. Paternal mitochondria which are introduced with spermatid have been observed up to 4-cell. Our study indicated that either round spermatid or it's nucleus can be used to produce viable bovine embryos by injection into unfertilized oocytes.

• The Korean Journal of Zoology
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• v.33 no.3
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• pp.365-372
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• 1990

For the effort to produce transgenic amphibians, a plasmid DNA sequence (cytoplasmic actin promoter-linked bacterial $\beta$-galactosidase gene) was microinjected into fertilized Xenopus eggs. It appeared that the injection of 20 nl solution containing 1-2 ng of DNA was not toxic, but over 4 ng was toxic to embryonic development. The translational product of $\beta$-gal gene ($\beta$-galactosidase) had enzyme activity in all three germ layers of the embryo. Expression of the injected $\beta$-gal genes was first detected at mid-gastrula stage, and the activity persisted up to stage 43 (feeding tadpole) with decreased level of retention. However, the level of the expression was various among the injected individuals as well as each experiment. That is, $\beta$-galactosidase activities did not appear in all cells, instead a localized distribution pattern. Although other possibilities could not be omitted, this mosaic distribution of gene expression seemed to arise from unequal partition of the injected DNA into each blastomere during early cleavage.

• Reproductive and Developmental Biology
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• v.29 no.3
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• pp.181-186
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• 2005

This experiment was conducted to investigate effects of the two different in vitro production systems, serumcontaining system (IVM, IVF and IVC; TCM199, TALP and CR1aa) and serum-free system (IVM, IVF and IVC; IVMD101, IVMD100 and IVMD101), on the development of in vitro fertilized or DNA-microiniected embryos. We also examined the effect of DNA dosage and its expression pattern in embryos. The DNA used for microinjection was a green fluorescence protein gene. The development rates to $\geq$ 2cell, 8cell and blastocyst stage were significantly higher in vitro fertilized embryos than those in DNA-microinjected embryos. The development rate to the 8-cell stage was significantly higher in serum-free system than in serum-containing system (p<0.05; $3.3\%\;vs.\;15.5\%\;and\;21.4\%$, respectively). The development rates to the blastocyst stage of in vitro fertilzed or DNA-microinjected embryos between two different culture system ($2.7\%\;vs.\;2.3\%\;and\;23.0\%\;vs.\;23.6\%$, respectively) were not different. The development rates of embryos injected 2 ng/uL DNA was higher. than those of embryos injected 4 or 8 ng/uL DNA. The GFP expression rate of 1-cell embryos was significantly higher than that of 2-cell and 4-cell embryos, whereas the rates were not different between 4-cell and blastocyst-stage embryos.

• Clinical and Experimental Reproductive Medicine
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• v.24 no.3
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• pp.301-309
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• 1997

The objective of this study was to determine the microtubule assembly and chromatin configuration during the first cell cycle in bovine oocytes following injection of spermatozoon, sperm head and tail. The microtubule and chromatin configuration was imaged with fluorescent labeled monoclonal ${\alpha}$-tubulin antibody and propidium iodide under laser scanning confocal microscope. Microtubule and chromatin dynamics in bovine oocytes following intracytoplasmic sperm injection (ICSI) were not different from those observed during in vitro fertilization (IVF). Following ICSI, the microtubular aster was observed around sperm midpiece. During pronuclear formation, the sperm aster was enlarged and seen around male and female pronuclei. At mitotic metaphase, the microtubular spindle assemble astral poles and chromosomes were aligned on the spindle equator. At mitosis, asters were concentrated to each spindle pole and they filled the cytoplasm. After injection of the isolated sperm head, the microtubular aster was not seen around sperm head in any cases (0/18). Instead, microtubules were organized from the cytoplasm, which filled the whole cytoplasm during pronuclear apposition. These microtubules seem to move male and female pronuclei. These results suggest that isolated sperm head can develop into normal pronucleus in mature bovine oocytes, and competent to participate syngamy with the ootid chromatin. The functional microtubules following isolated sperm head injection in bovine oocytes appeared to be organized solely from maternal stores.

• Korean Journal of Animal Reproduction
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• v.22 no.2
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• pp.195-202
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• 1998

We demonstrated, for the first time, pronuclear formation and apposition in porcine ooc-ytes following intracytoplasmic injection of porcine, human, bovine and mouse spermatozoon. Microtubule organization and chromatin configuration were investigated in these oocytes during pronuclear apposition. Following intracytoplasmic injection of porcine spermatozoon, the microtubular aster was organized from the neck of spermatozoon, and filled the whole cytoplasm. This male derived microtubules appear to move both pronuclei to the center of oocytes. In contrast, following injection of spermatozoa from different species such as human, bovine and mouse, microtubules were organized from the cortex of the oocytes and concentrated to the pronuclei, which seems to move both male and female pronuclei to the center of oocyte. This organization is similar to what has been shown in the parthenogenetically activated por-cine oocytes. These results suggested that the porcine, human, bovine and mouse sperm chromatin can be formed pronucleus and apposited in the center of oocytes in the absence of male derived microtubule when they were injected into porcine oocytes.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2004.11a
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• pp.19-20
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• 2004

본 연구는 1세포기 닭 수정란에서 외래 표지유전자(EGFP)와 리포좀(liposome)을 사용하여 외래유전자의 핵 전이의 효율성을 검증하고자 하였다. 실험은 리포좀과 혼합된 표지유전자와 naked 유전자 두 그룹으로 나누고, 유전자 미세 주입방법을 이용하여 배반엽 단계(stage X)와 1세포기 수정란의 세포질에 미세 주입하고 지속적으로 배양하면서 GFP의 발현 양상들을 관찰하였다. 실험결과, 배반엽 단계와 1세포기 수정란 모두에서 리포좀과 외래 유전자의 혼합물을 미세 주입한 경우 일주일 정도 지속적으로 GFP가 발현되었으나, 외래 유전자만을 주입한 경우 GFP의 발현이 관찰되지 않았다. 본 연구결과는 리포좀이 효율적으로 외래 유전자를 닭 수정란의 핵으로 이동시킴을 보여주고 있다.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.58-58
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• 2001

본 연구는 섬유소 분해효소 유전자 Cel D(Cellulase Digestion)가 도입된 형질전환 돼지 생산을 통하여 섬유소 함유 사료의 이용 효율을 증대시키고, 나아가 장기이식동물 및 고가의 의료용 단백질 생산가축을 개발하기 위한 원천기술 확보에 있다. 섬유소분해 유전자의 크로닝 및 조직 특이적 발현벡터를 개발하기 위하여, 우선 소의 위중 제4위 내의 미생물로부터 전체 유전자를 분리하였고, 이렇게 작성된 DNA library에서 섬유소분해 관련 유전자인 약 2.0 kb의 Cel D유전자를 크로닝하였으며, 췌장 특이적 발현 프로모터(rat elastase I: 약 200bp)를 크로닝한 후, 미세주입용 형질전환 재조합 벡터를 구축하기 위하여 rElastase I 프로모터 하류에 섬유소 분해 유전자(Cel D)를 연결하여 약 3.0 kb 크기의 재조합 벡터를 준비하였으며, 재조합 유전자를 1세포기 수정란 전핵내에 미세주입 하기 위해 Sal I과 BglII를 이용 유전자 단편을 만들었다. 구축된 유전자를 미세주입하기 위한 수정란을 회수하기위해 총68두의 돼지를 4-5두씩 분리사육하면서 발정동기화 및 과배란 유기를 위해 PG600, Altrenogest, FSH, hCG를 투여하였으며 hCG투여후 약54시간에 외과적 방법에 의해 총 1,359개의 수정란을 회수하였고, 이중 미세주입가능한 1세포기 수정란은 1,296개로 두당 평균 15.9개 였다. 1,296개의 1세포기 수정란 중에서 재조합 유전자(rE I-CelD)가 미세주입된 660개의 수정란을 32두의 수란돈에 외과적 방법에 의해 이식하였으며, 이식되어진 모돈 13두가 분만하여 40.6%의 임신율을 나타내었다. 이렇게 분만된 13두에서 총 65두(암:33두, 수:32두)의 자돈이 생산되었으며, 형질전환 여부를 판명하기 위해 자돈의 꼬리조직으로 부터 genomic DNA를 추출하고 PCR 검정을 실시하였다. PCR 검정 결과, 섬유소 분해 유전자가 도입된 자돈은 5두 이었으며, 그 결과를 Table에 나타내었다.(Table Omitted) Table 1 에서와 같이 섬유소 분해효소유전자가 형질전환된 자돈은 65마리 중 5마리로 7.69%의 형질전환율을 나타내었으며, 5마리의 자돈중 2두(암:1두, 수:1두)는 분만 후 즉시 폐사되었으며 2두(암:1두, 수:1두)는 86일령 그리고 14일령에 폐사하여 현재 1두(암)가 생존하여 섬유소 분해 사양 실험 중에 있다.