• Korean Journal of Crystallography
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• v.5 no.1
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• pp.39-50
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• 1994

Diamond thin films were deposited on silicon, molybdebum, titanum and tugsten substrates, and were chlwntnizen using scanning electron microscopy, X-ray diffraction analysis and Raman spectroscopy. From the result of experiment in various deposition periods, it was found that found that were nucleated and grown on interlayed carbide layers, which were formed on refractory metal substrates at the initial stage of.

• The Korean Journal of Zoology
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• v.33 no.1
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• pp.1-5
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• 1990

The comparative karyological analysis of the Korean treefrogs, Hyla japonica and Hyla suweonensis, were performed by C-banding method. Heteromorphic sex chromosomes, female heterogamety, has been identified in the 3rd chromosomes of H. suweonensis H. suweonensis seem to have sex chromosomes which are Zz/ZW type. The Z chromosomes contain large amount of constitutive heterochromatin, but little heterochromatin is located in the W chromosomes. This is in contrast to all previously known amphibian and most other vertebrate's W or Y chromosomes, except Gastrotheca oui'ern and G. walken (Schmid et al., 1988).

• Clinical and Experimental Pediatrics
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• v.52 no.5
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• pp.603-606
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• 2009

The Pierre Robin sequence (PRS) is the nonrandom association of micrognathia, cleft palate, and glossoptosis, leading to respiratory and feeding difficulties that appear neurogenic rather than mechanical in causation. Genetic determinants are thought to underlie this functional and morphological entity, based on the existence of Mendelian syndromes with PRS. Here, we demonstrate the association of PRS with trisomy 8p due to duplication of a segment as the karyotype 46,XX,dup(8)(p21.3p23.1) and confirm the additional materials as chromosome 8 via whole chromosome paint probes. Our observation supports the hypothesis regarding a genetic basis for nonsyndromic PRS, strengthens the possible genetic association with isolated cleft palate, and provides a candidate PRS locus in chromosomal region 8(p21.3p23.1).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.1 no.1
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• pp.27-32
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• 2000

Porous glass ceramics composed of $Ag_2-Li_2O-CaO-TiO_2-P_2O_5$-CaO with 0.05-1.5 mole CuO were prepared by melting and 2 step heat treatment for nucleation at $610^{\circ}C$ and crystallization at $840^{\circ}C$. $\beta$-$Ca_3(PO_4)_2$crystal phase was selectively leached out in 1N-HC1 solution for 3 days, leaving $AgTi_2(PO_4)_3$and $LiTi_2(PO_4)_3$crystal phases. Antibacterial effects and characterizations of the porous glass ceramics were investigated. Staphylococcus aureus and Salmonella typhi bacteroa were used in this study. It was found that the resultant porous glass ceramics show excellent bacteriostatic properties.

• Journal of Convergence for Information Technology
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• v.8 no.5
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• pp.95-100
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• 2018

The metal oxide/graphene nanocomposites are promising functional materials for high capacitive electrode material of secondary batteries, and high sensitive material of high performance gas sensors. In this study, vanadium dioxide($VO_2$) nanostructrures were grown on CVD graphene which was synthesized on Cu foil by thermal CVD, and exfoliated graphene which was exfoliated from highly oriented pyrolytic graphite(HOPG) using a vapor transport method. As results, $VO_2$ nanostructures on CVD graphene were grown preferential growth on abundant functional groups of graphene grain boundaries. The functional groups are served to nucleation site of $VO_2$ nanostructures. On the other hand, 2D & 3D $VO_2$ nanostructures were grown on exfoliated graphene due to uniformly distributed functional groups on exfoliated graphene surface. The characteristics of morphology controlled growth of $VO_2$/graphene nanocomposites would be applied to fabrication process for high capacitive electrode materials of secondary batteries, and high sensitive materials of gas sensors.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.156-156
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• 1999

자성박막에 존재하는 자기구역의 형상 및 동력학은, 자성박막의 학문적 연구와 응용기술 개발의 핵심을 제공하는 매우 중요한 분야의 하나로서, 최근 크게 관심이 고조되고 있다. 본 연구에서는 차세대 광자기 재질로 각광받고 있는 Co/Pd 다층박막에서의 자기구역 형상 및 자기구역 동력학을 연구하였다. 전자빔 진공증착 시스템을 사용하여, Co 층의 두께와 Pd층의 두께, 그리고 전체 층수가 변화하는 일련의 Co/Pd 다층박막 시료를 제작하였다. 제작된 모든 시료가 명목두께에 대하여 4%의 정밀도로 제작되었음을 확인하였고, 제작된 시료의 자기 및 광자기 성질은 자기이력곡선 등을 측정하였다. 또한 고성능 광자기 Kerr 현미경 시스템을 이용하여 자성박막에 존재하는 자기구역의 형상 및 자기구역 동력학을 관찰하였다. 이 장비는 1,000배의 배율에서 0.3$\mu\textrm{m}$의 공간분해능을 가지며 실시간 자기구역 영상을 CCD 카메라를 통해 컴퓨터에 저장함으로써, 자지구역 거동현상을 관찰할 수 있다. 자성다층박막에 존재하는 자기구역의 형상을 이론적으로 예측하기 위하여, 다층박막 구조에서의 정자기 에너지를 일반적으로 계산할 수 있는 이론을 유도하였다. 이 이론을 통해 다층박막의 자성층의 두께가 두꺼워짐에 따라, 자기구역의 형상이 단일 자기구역 형상에서 줄무늬 자기구역 형상으로 천이함을 예측할 수 있었고, 이러한 지구구역 천이현상을 Co-Pd 다층박막의 자화역전현상을 연구하였고, 새로운 자구동력학 정량분석기술을 개발하여 Co/Pd 다층박막에 적용함으로써 자화역전의 자구벽 이동속도와 핵형성 확률을 각각 정량적으로 구하였다. 이러한 관찰 및 분석기술을 통하여, Co/Pd 다층박막의 층구조에 따라 대조적인 자화역전현상이 존재함을 관찰하였다. 이러한 대조적인 자화역전현상을 결정짓는 요인을 연구하기 위해서 나노자성학이온을 이용한 자화역전현상을 결정짓는 요인을 연구하기 위해서 나노자성학이온을 이용한 자화역전모델을 개발하였으며, 이를 통하여 자성박막의 거시적 자기성질에 의해 이러한 대조적인 자화역전모델을 개발하였으며, 이를 통하여 자성박막의 거시적 자기성지에 의해 이러한 대조적인 자화역전현상이 결정될 수 있음을 설명하였다. 또한, 미시적 자기이력곡선 측정을 통하여 자성박막구조에 따른 국소적인 구조불균일성을 관찰하였고, 이러한 구조불균일성 또한 대조적인 자화역전현상을 결정하는 큰 요인임을 논의하였다.

• Journal of Genetic Medicine
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• v.5 no.1
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• pp.47-54
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• 2008

Purpose : Fluorescence in situ hybridization (FISH) on uncultured amniotic fluid cells offers the opportunity for rapid screening of aneuploidies and has become an integral part of the current practice in many clinical cytogenetics laboratories. Here, we retrospectively analyzed the results of interphase FISH in 943 amniotic fluid samples and assessed the efficiency of FISH for rapid detection of aneuploidies. Methods : Interphase FISH for chromosome 13, 18, and 21 was performed in 943 consecutive amniotic fluid samples for rapid diagnosis of aneuploidies referred from 2004 to 2006. Karyotypes from standard cytogenetic analysis were compared to the FISH results. Results : A total of 45 chromosomal rearrangements (4.8%) were found after conventional cytogenetic analysis of the 943 amniotic fluid. After exclusion of known familiar chromosomal rearrangements and inversions (2.1%, 20/943), 2.7% (25/943) were found to have chromosomal abnormalities. Of this group, 0.7% (6/943) were chromosomal abnormalities not detectable by FISH and 2.0% (19/943) were numerical abnormalities detectable by FISH. All 14 cases of Down syndrome (Classic type, 13 cases; Robertsonian type, 1 case) and 5 cases of trisomy 18 were diagnosed and detected by FISH and there were no false-positive or -negative results (specificity and sensitivity=100%). Conclusion : The present study demonstrates that FISH can provide a rapid and sensitive clinical method for prenatal identification of chromosome aneuploidies. However, careful genetic counseling is essential to explain the limitations of FISH, including the inability to detect all chromosomal abnormalities and the possibilities of uninformative or false-negative results in some cases.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.64-64
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• 1999

다결정 실리콘-게르마늄(poly-SiGe)은 태양전지 및 TFT-LCD와 같은 소자 응용에 있어서 중요하게 연구되고 있는 물질이다. 우리는 수소화된 비정질 실리콘-게르마늄 (a-Si1-xGex:H) 박막을 증착시키고 고상결정화시키며 XRD(x-ray diffraction) 및 ESR (electron spin resonance) 측정을 수행하였다. PECVD 증착가스는 SiH4과 GeH4가스를 사용하였고 Ge의 성분비는 x=0.0, 0.1, 0.5 정도로 조절되었다. 기판은 Corning 1737 glass를 사용하였고, 기판 온도는 20$0^{\circ}C$ 이었다. 증착압력과 r.f. 전력은 각각 0.6Torr와 3W이었다. 증착된 SiGe 박막은 고상결정화를 위해 $600^{\circ}C$ N2 분위기에서 가열되고, 그에 따른 XRD 및 ESR spectrum의 변화를 관찰하였다. ESR 측정은 X-band 그리고 상온에서 행해졌다. 먼저 XRD 측정으로부터 박막의 고상결정화 정도를 알 수 있었고, 고상결정화 과정이 초기 핵형성 단계와 결정화 단계, 그리고 더 이상 결정화가 일어나지 않는 완료 단계로 구분될 수 있음을 보여주었다. X값이 증가함에 따라 결정화 시간은 훨씬 단축되었다. ESR로 측정된 스핀 밀도는 a-Si1-xGex:H 박막이 처음 가열됨에 따라 전체적으로 크게 증가했다가, 결정화가 일어나면서 다시 감소하여 나중에는 거의 변화가 없었다. ESR 신호의 초기 증가는 수소 이탈에 의한 dangling bond의 증가에 기인하며, 다음 단계의 감소 및 안정 상태는 결정화에 따른 결정경계 영역의 감소와 결함들의 안정성에 기인하는 것으로 생각된다. 그러나 흥미로운 것은 Si1-xGex 합금의 경우 가열시간이 증가됨에 따라 Si-db(Si-dangling bond)와 Ge-db에 의한 신호가 서로 분리되어 나타났으며, 이 Si-db 스핀 밀도와 Ge-db 스핀밀도의 변화정도는 x값에 크게 의존함을 보여준 것이다. 즉 순수한 a-Si:H의 경우 Si-db 의 스핀밀도의 증가시간은 4시간 정도였고, 그리고 다시 감소하였으며, x=0.1 인 박막에서 Si-db와 Ge-db의 변화 시간은 순수 S-db 변화의 경우와 거의 유사하였다. 그러나 x=0.5 샘플에서는 Si-db의 변화가 빨라져서 0.1 시간 안에 증가되었고, Ge-db의 변화는 더 빠르게 수 분 동안에 증가 된후 다시 감소하였다. 이것은 수소의 Si에 대한 친화력 뿐 만아니라 Si-H과 Ge-H 결합에너지가 주위 원자들의 구성에 크게 영향받을 수 있는 가능성을 제시해준다.

• Journal of Embryo Transfer
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• v.20 no.3
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• pp.201-206
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• 2005

This study was conducted to investigate the effects of oocyte activation after ICSI and of capacitation of insemination sperm before ICSI in Swine. There was no significant difference on cleavage rate and blastocyst developmental rate treated with ethanol, cycloheximide, or ethanol and cycloheximide jointly between treatment and control groups. However, significantly difference was found on cleavage rate and blastocyst developmental rate treated with caffeine and Ca-ionophore on capacitation of insemination sperm before ICSI (p<0.05). There was no significant difference on pronuclear formation rate and total oocyte activation rate treated with oocyte activation after ICSI between treatment and control groups, but was significant difference on pronuclear formation rate and total oocyte activation rate treated with capacitation treat of sperm (p<0.05).

• Applied Chemistry for Engineering
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• v.18 no.1
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• pp.94-97
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• 2007

Carbon nanotubes and nanowires were prepared by methane pyrolysis over Pd(5)/SPK catalyst by changing oxygen molar ratio in a fixed bed flow reactor under atmospheric condition and also analyzed by SEM and TEM. When the $CH_4/O_2$ molar ratio was 1, carbons were not almost deposited on the catalyst bed support, but when it was 2, carbons were deposited as much as plugging reactor. TEM and SEM images for the deposited carbons showed a number of single-walled carbon nanotubes and carbon nanowires. The growth mechanism of carbon nanotubes produced on the catalyst surface was the tip growth mode. It should be played an important role in carbon nanotubes and nanowires produced on the catalyst bed support to formate the carbon growth velocity vectors and nuclei of ring structure of carbon nanowires. SPK carrier was $N_2$ isotherm of IV type with mesopores, and excellent in the thermal stability.