• Korean Journal of Medicinal Crop Science
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• v.16 no.3
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• pp.195-198
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• 2008

Karyotypic analysis and FISH (fluorescence in situ hybridization) with 45S and 5S rRNA genes were carried out in Persicaria tinctoria H Gross. The somatic metaphase chromosomes were ranged from 2.25 ${\mu}m$ to 1.50 ${\mu}m$ in length. Chromosome number was 2n = 4x = 40 with the basic number of x = 10. The chromosome complement of the species consisted of 16 pairs of metacentrics (chromososomes 1,2,3,4,6,7,8,9, 10, 11, 12, 13, 15, 18, 19 and 20) and 4 pairs of submetacentrics (chromosome 5, 14, 16 and 17). The karyotype formula was K(2n) = 4x = 32 m + 8 sm. In FISH analysis, three pairs of 45S rRNA gene loci on the terminal region of submetacentrics (chromosomes 5, 16 and 17) and two pairs of 5S rRNA gene loci on the centromeric region of metacentrics (chromosomes 9 and 11) were detected, respectively.

• Parasites, Hosts and Diseases
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• v.25 no.2
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• pp.154-158
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• 1987

As a series of systematic classification of paramphistomes, the worms in the rumen and reticulum were collected on 214 Korean cattle slaughtered at Jeonju abattoir from January, 1986 to April, 1987 and were classified by means of morphology. Afterwards, the karyotype of Paramphistomum cervi(Zeder, 1790) was detected by means of modified air.drying method from germ cells of the worms. The results were summarized as follows: 1. In the chromosome number of 254 p. cervi, the haploid cell was n:9 and the diploid 2n=18. The meiotic divisions were observed frequently; 1,924 haploid and 32 diploid cells were reliable. Nine pairs of mitotic chromosomes were homologous in the metaphase stage, and the chromosomes were composed of five medium-sized metacentrics (m) , subtelocentrics(st) or submetacentrics(sm) and four small-siRed subtelocentrics(st) or submetacentrics(sm). Meiotic metaphase was composed of five medium and four small chromosomes in size. 2. As a series of C-banding method, C-band was showed in centromeric region from all of the haploid germ cells. Whereas chromosome No. 3 and 5 included heterochromatin on the tip region, chromosome No. 4 on the distal region and No. 6 proximal region. And chromosomes No. 2 and 8 showed a remarkable C-band distinguished from other chromosomes.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.7
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• pp.77-83
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• 2022

When carbon dioxide in a liquid becomes supersaturated, carbon dioxide gas bubbles are generated in the liquid, and they ascend to the surface as they develop further. At this time, the inner wall of the cup with carbon gas attached is known as the entrapped gas cavity (EGS); once an EGS is established, it does not disappear and will continuously create carbon bubbles. This bubbling phenomenon can be activated or suppressed by changing the properties of the solid surface in contact with the carbonated liquid. In this study, the foaming of carbonated liquid is promoted or suppressed by modifying the wettability of the surface. A micro/nano surface structure is formed on the surface of an aluminum cup to produce a superhydrophilic surface, and a superhydrophobic surface similar to a lotus leaf is synthesized via fluorination. Experiment results show that the amount of carbon dioxide bubble generated differs significantly in the first few seconds depending on the surface, and that the amount of gas generated after it enters the stabilization period is the same regardless of the wettability of the cup surface.

• Journal of Genetic Medicine
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• v.7 no.1
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• pp.82-86
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• 2010

Jumping translocations (JT) are chromosomal rearrangements involving one donor chromosome and several recipient chromosomes. While JTs are frequently observed as acquired chromosomal abnormalities in hematologic malignancies, constitutional JTs are only rarely reported. We report two cases of constitutional JT in chorionic villi derived from the products of conception. The karyotype of the first case was 46,XY,add(18)(p11.1)[61]/45,XY,der(18;21)(q10;q10)[32]/46,XY,-18,+mar[16]/46,XY,i(18)(q10)[9]/45,XY,der(15;18)(q10;q10)[6]/46,XY,+1,dic(1;18)(p22;p11.1)[2]/45,XY,der(13;18)(q10;q10)[1]/46,XY[32]. The donor was a chromosome 18. The recipient chromosomes were chromosomes 1, 13, 15, 18 and 21. In the second case, the karyotype was 46,XY,der(22)t(9;22)(q12;q13)[22]/46,XY,der(22)t(1;22)(q21;q13)[13]/46,XY,add(22)(q13)[5]/46 XY[23]. The donor was a chromosome 22 and recipients were chromosomes 1 and 9. Both cases were de novo. The breakpoints of chromosomes were mostly in centromeric regions, pericentromeric regions, or telomeric regions. Normal cell lines were observed in both cases. This report supports the prior findings that the unstable nature of JT, resulting in chromosomal imbalance, most likely contributed to these early miscarriages.

• Journal of Genetic Medicine
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• v.6 no.1
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• pp.62-66
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• 2009

Purpose: Chromosomal abnormalities of abortuses have been used to investigate common etiologies of spontaneous abortion, but the frequencies and types of spontaneous abortions have demonstrated considerable variation among different countries and races. Materials and Methods: A cytogenetic analysis of 75 abortuses was performed at GenDix, Inc. from January 2006 to December 2007. Results: The frequency of chromosome abnormalities in abortuses was 32.0% (24/75 cases). Among the chromosomal abnormalities, trisomy was present in 62.5% (15/24 cases) of cases and the most frequent trisomy was trisomy 21 with an occurrence rate of 26.6% (4/15 cases). The following was trisomy 22 (3/15 cases) and trisomy 20 (2/15 cases). The average maternal age for abnormal karyotypes was $34.3{\pm}3.3$. Conclusion: Cytogenetic analysis of abortus is important for diagnosis and genetic counseling of patients with spontaneous abortion.

• Journal of Genetic Medicine
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• v.7 no.2
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• pp.111-118
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• 2010

Chromosomal microarray analysis (CMA) enables the genome-wide detection of submicroscopic chromosomal imbalances with greater precision and accuracy. In most other countries, CMA is now a commonly used clinical diagnostic test, replacing conventional cytogenetics or targeted detection such as FISH or PCR-based methods. Recently, some consensus statements have proposed utilization of CMA as a first-line test in patients with multiple congenital anomalies not specific to a well-delineated genetic syndrome, developmental delay/intellectual disability, or autism spectrum disorders. CMA can be used as an adjunct to conventional cytogenetics to identify chromosomal abnormalities observed in G-banding analysis in constitutional or acquired cases, leading to a more accurate and comprehensive assessment of chromosomal aberrations. Although CMA has distinct advantages, there are several limitations, including its inability to detect balanced chromosomal rearrangements and low-level mosaicism, its interpretation of copy number variants of uncertain clinical significance, and significantly higher costs. For these reasons, CMA is not currently a replacement for conventional cytogenetics in prenatal diagnosis. In clinical applications of CMA, knowledge and experience based on genetics and cytogenetics are required for data analysis and interpretation, and appropriate follow-up with genetic counseling is recommended.

• Applied Chemistry for Engineering
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• v.34 no.2
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• pp.111-120
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• 2023

The nucleation mechanism was studied using a calcium ion selective electrode (Ca ISE) to observe the formation of CaCO₃, a representative mineral in the CO2 cycle, and to analyze the effect of the Mg/Ca-ratio and temperature on the formation of pre-nucleation cluster (PNC) and CaCO₃. As a result of the experiment, a small amount of crystal was formed. Energy dispersive X-ray spectroscopy (EDS) was used for surface element analysis, and a field emission scanning-electron microscope (FE-SEM) was used for the morphology analysis of synthesized carbonates. These results showed that various shapes of crystalline CaCO₃ (calcite, aragonite, etc.) were observed for each Mg/Ca ratio and temperature. In addition, the calibration plot obtained from Ca ISE showed information on the formation process of CaCO₃. Our results showed that as magnesium ions interfered with the binding of calcium and carbonate ions and delayed the aggregation between PNCs, the nucleation and formation of CaCO₃ were delayed. On the other hand, the temperature showed an opposite trend as compared to the effect of magnesium under our experimental conditions, indicating that temperature accelerated the formation of CaCO₃. Furthermore, the morphology of CaCO₃ clearly changed according to the Mg/Ca ratio and temperature, and it was confirmed that the two factors are very important for CaCO₃ formation in that they could affect the overall process.

• Korean Journal of Ichthyology
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• v.24 no.1
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• pp.1-10
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• 2012

Reciprocal hybrids between the mud loach ($Misgurnus$ $mizolepis$) and cyprinid loach ($M.$ $anguillicaudatus$) were produced by artificial fertilization. The chromosome number of mud loach was 2n=48, consisting of 12M+4SM+32A chromosomes. The cyprinid loach has 2n=50, consisting of 10M+4SM+36A chromosomes. The chromosome numbers of the diploid reciprocal hybrids were 2n=49, consisting of 11M+4SM+34A chromosomes. All the karyotypes documented in this study had the same arm number of 64. There was no evidence of chromosomal polymorphisms or sex-related heteromorphism. The cytogenetic traits of the hybrid genotypes were intermediate between those of the parent species. In all genotypes, the chromosomal NORs localized to the terminal short arms of the same metacentric chromosome pair. These results suggest that Robertsonian translocation occurred between metacentric chromosome 1 of mud loach and acrocentric chromosome of cyprinid loach.

• 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.

• 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.