• Journal of electromagnetic engineering and science
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• 제8권3호
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• pp.134-137
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• 2008

This paper proposes a novel quadrature VCO(QVCO) based on direct back-gate second harmonic coupling. The QVCO directly couples the current sources of the conventional LC VCOs through the back-gate instead of front-gate to generate quadrature signals. By the second harmonic injection locking, the two LC VCOs can generate quadrature signals without using on-chip transformer, or stability problem that is inherent in the direct front-gate second harmonic coupling. The proposed QVCO is implemented in $0.18{\mu}m$ CMOS technology operating at 2 GHz with 5.0 mA core current consumption from 1.8 V power supply. The measured phase noise of the proposed QVCO is - 63 dBc/Hz at 10 kHz offset, -95 dBc/Hz at 100 kHz offset, and -116 dBc/Hz at 1 MHz offset from the 2 GHz output frequency, respectively. The calculated figure of merit(FOM) is about -174 dBc/Hz at 1 MHz offset. The measured image band rejection is 46 dB which corresponds to the phase error of $0.6^{\circ}$.

• 한국육종학회지
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• 제40권3호
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• pp.243-249
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• 2008

In the previous study, 141 $BC_3F_2$ lines from a cross between the Oryza sativa cv. Milyang 23 and O. glaberrima were used to identify favorable wild QTL alleles for yield component traits. In this study, we carried out QTL analysis of four grain morphology as well as four yield component traits using 141 $BC_3F_5$ lines from the same cross and compared QTLs detected in two different generations. The mean number of O. glaberrima segments in the 141 $BC_3F_5$ lines ranged from 1 to 13 with 2.69 and 5.71 of the average means of homozygous and heterozygous segments, respectively. There was a three-fold difference in the number of QTLs detected for four traits commonly evaluated in two generations (seven QTLs in the $BC_3F_5$ vs 21 in the $BC_3F_2$ population). The percentages of the phenotypic variance explained by QTLs in the BC3F5 population were similar to or less than those in the $BC_3F_2$ population. This is probably due to the difference in the genetic composition of two populations and the environmental effects. The locations of the QTLs commonly detected in both generations were in good agreement except for one QTL for spikelets per panicle. The yield QTL, yd3 was colocalized with the spikelets per panicle, spp3. Yield increase at this locus is due to the increase in spikelets per panicle, because both traits were associated with increase in spikelets per panicle and yield due to the presence of an O. glaberrima allele. Clusters of QTLs for grain morphology traits were observed in two chromosome regions. One cluster harboring five QTLs near SSR markers RM106 and RM263 was detected on chromosome 2. This population would serve as a foundation for development of the introgression line population from a cross between Milyang 23 and O. glaberrima.

• 농업과학연구
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• 제41권1호
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• pp.1-7
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• 2014

Ratooning ability is one of the major different traits from perennial to cultivated rice and annual type. We developed a set of 126 introgression lines derived from a cross between Hwayeong and W1944 (O. rufipogon) to gain an insight into the genetic factors underlying differences between common wild rice and cultivated rice. One IL, CR6 among the 126 ILs of $BC_3F_4$ showed a significant difference in rationing ability compared with Hwayeong. To further characterize the rationing ability, CR6 was selected and crossed to Hwayeong to produce three secondary populations, $BC_4F_2$, $BC_4F_3$ and $BC_5F_2$. In the Hwayeong background, the W1944 allele was associated with an increase in rationing ability. QTL analysis showed that the qRAT5 for rationing ability was linked to RM194 ($R^2$=6.6%, 19.6%, and 44.5% in the $BC_4F_2$, $BC_5F_2$, and $BC_5F_3$, respectively). The putative qRAT5 was also tightly linked to QTLs for spikelets per panicle and grain weight indicating that this region harbors a QTL cluster related to domestication. To our knowledge, this is the first report to map the major QTL for ratooning ability in rice. The SSR markers linked to qRAT5 would be useful in marker-assisted selection for breeding lines with enhanced ratooning ability.

• Genomics & Informatics
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• 제20권4호
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• pp.42.1-42.11
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• 2022

Breast cancer (BC) is a significant threat to female health, with both modifiable and non-modifiable risk factors. It is essential to monitor patients regularly and to raise population awareness. Increasing research also suggests that E-selectin (SELE) may increase tumor angiogenesis and the development of cancer. This study investigated SELE single-nucleotide polymorphisms (SNPs) in the following positions: rs5367T/C, rs5368C/T, rs5362T/G, and rs5362T/C. Using polymerase chain reaction, significant differences in allele and genotype frequencies were found between BC patients and controls. Position rs5368 was associated with an increased risk of BC for the CT and TT genotypes, with odds ratios (ORs) of 16.3 and 6.90 (Fisher probability = 0.0001, p = 0.005). Women with the T allele had a 19.3-fold higher incidence of BC, while allele C may be a protective allele against BC (OR, 0.05). Heterozygous genotypes at rs5367, rs5362, and rs5362 were significantly more common in BC patients, with ORs of 5.70, 4.50, and 3.80, respectively. These SNPs may be associated with the risk of BC, because the frequency of mutant alleles was significantly higher in patients (OR: 4.26, 3.83, and 4.30, respectively) than in controls (OR: 0.23, 0.30, and 0.20, respectively). These SNPs may be considered a common genotype in the Iraqi population, with the wild-type allele having a protective fraction and the mutant allele having an environmental fraction. The results also revealed a 2-fold increase in gene expression in BC patients compared to controls, with a significant effect (p = 0.017). This study's findings confirm the importance of SELE polymorphisms in cancer risk prediction.

• 한국정보통신학회논문지
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• 제14권3호
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• pp.541-546
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• 2010

LTCC(low temperature co-fired ceramic) 공정의 다층기판을 이용하여 push-push 유전체 공진 발전기를 설계 및 제작하였다. 중심주파수 8GHz를 갖는 직렬 궤환형의 단일 유전체 공진 발진기를 설계하고 이를 이용하여 중심주파수 16GHz인 push-push 유전체 공진 발진기를 설계하였다. 발전기의 회로 크기에 큰 영향을 미치는 바이어스 회로를 LTCC 다층구조의 중간층에 배치함으로써 일반적인 단층기판을 이용한 경우에 비해 발진기 회로의 크기를 크게 줄 일 수 있었다. 제작된 push-push 유전체 공진 발진기의 측정결과 기본 주파수 및 3차 고조파 억압특성은 각각 15dBc 및 25dBc 이상의 특성을 나타내었으며 발진기의 위상잡음 특성은 -102dBc/Hz@100KHz 및 -128dBc/Hz@1MHz의 특성을 각각 나타내었다.

• 미생물학회지
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• 제49권3호
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• pp.262-269
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• 2013

본 연구진은 청국장에서 수종의 미생물을 분리하였으며, 이중 소화 효소능이 뛰어난 균주를 선별하였으며, 유전학적 분석결과를 통해 본 균주가 Bacillus 속 균주임을 확인하고 Bacillus subtilis BC-P1이라 명명하였다. Bacillus subtilis BC-P1을 starter로 사용하여 청국장을 제조하였으며, protease, xylanase, chitinase activity, 혈전 분해능, 영양성분 분석 및 아미노산 분석을 통하여 B. subtilis BC-P1를 starter로 활용한 청국장 제품의 개선 가능성을 타진하였다. Bacillus subtilis BC-P1를 starter로 제조한 청국장은 기존 제품에 비해 우수한 소화효소 생성능을 보였으며, 특히 혈전분해효소 생성능이 우수함을 확인하였고, 대조군에 비해 증가된 환원당 및 총 아미노산 함량을 확인 할 수 있었다. 따라서 본 균주를 starter로 하여 청국장을 제조할 경우 기능성분, 생리활성의 증가, 품질 향상을 기대할 수 있을 것으로 판단되며, 향후 대규모 생산시 균주, 제조 조건에 관한 연구가 필요할 것으로 사료된다.

• 한국대기환경학회지
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• 제31권5호
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• pp.472-481
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• 2015

Black carbon (BC) aerosols were monitored at the KIST site ($37.603^{\circ}N$, $127.046^{\circ}E$) and Cheonan-KOREATECH site ($36.766^{\circ}N$, $127.281^{\circ}E$) during the pre KORea-US Air Quality Study (KORUS-AQ) campaign using a couple of Muliti Angle Absorption Photometers (MAAP). BC mass concentrations were presented as $2.14{\pm}1.06{\mu}g/m^3$ and $0.94{\pm}0.60{\mu}g/m^3$ at KIST site (Seoul) and KOREATECH site (Cheonan), respectively. BC mass concentrations measured at KIST and KOREATECH sites from 22:00 on May 22 to 12:00 on May 23, 2015 showed 80% and 72% higher than average BC mass concentrations measured during campaign period, respectively. It indicates both sites could be influenced by a remote source. Similar patterns of BC concentrations between two sites from 20:00 to 24:00 on June 6, 2015 implies that the BC could be transported into both sites and then be stagnant inside the Korean Peninsula. Diurnal variation of BC in weekdays and weekends were also presented for the KIST and KOREATECH sites. Morning rush hour peak was observed at KIST site located in metropolitan area though no distinct morning rush hour peak was not observed at KOREATECH site located in a suburban area. This study revealed transport pathways of BC near the Korean Peninsula using back-trajectory analysis of BC measured both in a metropolitan area and in a suburban area.

• 한국인터넷방송통신학회논문지
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• 제16권6호
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• pp.231-237
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• 2016

본 논문에서는 스위치드 본드와이어 인덕터 뱅크를 사용하여, 넓은 주파수 튜닝범위를 갖는 다중대역 저잡음 CMOS 전압제어발진기가 제안되었다. 본드와이어 인덕터와 CMOS 스위치의 결합으로 주파수 튜닝범위는 증가하고, 위상잡음은 개선되었다. 제안된 다중대역 CMOS 전압제어발진기는 2.3GHz부터 6.3GHz까지의 주파수에 대해 동작하며, 위상잡음은 1MHz 오프셋 주파수에 대해, 각각 -136dBc/Hz와 -122dBc/Hz를 나타내었다. 스위치드 본드와이어 인덕터 뱅크는 각 주파수 대역에서 높은 Quality factor(Q)를 나타내어, 위상잡음과 전력소모량 사이의 trade-off를 더욱 원활하게 해 준다. 제안된 전압제어발진기는 TSMC 0.18um CMOS공정을 사용하여 설계되었고, 7.2mW의 전력을 사용하며, 6GHz 발진주파수에 대해 1MHz 오프셋 주파수에서 -189.3dBC/Hz의 성능지수(FOM)를 나타내었다.

• Journal of Microbiology and Biotechnology
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• 제16권7호
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• pp.1090-1096
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• 2006

O-Methylation is a common modification reaction found in nature, and is mediated by an O-methyltransferase (OMT). OMTs have been mainly studied in plants, whereas only a few OMTs have been studied in microbes. When searching the Bacillus cereus genome, four putative small molecular OMTs were identified, among which BcOMT-1 was cloned and expressed in E. coli as a his-tag fusion protein. The whole cell expressing BcOMT-1 was used to methylate several flavonoids. Eriodictyol, luteolin, quercetin, and taxifolin, all of which contain 3' and 4' hydroxyl groups, served as methyl group acceptors for BcOMT-1, whereas naringenin, apigenin, 3,3'-dihydroxyflavone, and 3,4'-dihydroxyflavone did not function as substrates. Analysis of the reaction products using HPLC showed two different peaks, and NMR revealed that the methylation position was at the hydroxyl group of either carbon 3' or 4'. Therefore, this showed that BcOMT-1 used flavonoids containing ortho hydroxyl groups and transferred a methyl group to either of two hydroxyl groups.

• 대한전자공학회논문지TC
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• 제44권7호통권361호
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• pp.7-11
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• 2007

본 논문에서는 다중밴드 직접 변환 수신기를 위한 Octa-Phase 전압 제어 발진기를 제안하였다. Octa-Phase 신호와 저 위상잡음을 얻기 위해 4개의 LC VCO를 직렬 커플링 트랜지스터를 이용해 연결하였다. 멀티 밴드 특성을 얻기 위해 밴드 튜닝 회로가 제안되었다. MOS 스위치가 켜짐/꺼짐에 따라서 주파수 범위는 변화한다. 2개의 veractor를 사용해 VCO의 발진 주파수의 공정상의 오차를 최소화하였다. 본 논문에서는 0.18 um CMOS 공정을 이용해 발진기를 설계하였다. 측정 결과 1.8V 공급전압에 12mA의 전류를 소모하였고, $885MHz^{\sim}1342MHz$ 사이의 범위에서 동작하여 3개의 표준(CDMA 20001x, WCDMA, WiBro)에서의 sub-harmonic 혼합기를 구동시킬 수 있는 동작 범위를 만족시킨다. 측정된 위상잡음은 각각 CDMA 2000 1x 대역에서는 -105dBc@100kHz, WCDMA 대역에서는 -115dBc@1MHz, WiBro 대역에서는 -130dBc@10MHz으로 나타났다.