• 천문학회보
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• 제45권1호
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• pp.42.2-42.2
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• 2020

We report on multi-wavelength observations of AA Ori, a Young Stellar Object in Orion-A star-forming region. AA Ori is known to have a pre-transitional disk based on infrared observations including Spitzer/IRS data. We construct its broadband spectral energy distribution (SED) by not only taking data in the optical and IR region but also including Herschel/PACS, JCMT/SCUBA, and SMA observational data. We use the Monte Carlo radiative transfer code (RADMC-3D) to reconstruct the SED with a viscous accretion disk model initialized by a radially continuous disk and finally having an inner and outer dusty disk separated by a dust-depleted radial gap. By comparing the model SEDs with different configurations of disk parameters, we discuss the limits to find a single solution of model parameters to fit the data. We suggest that some models with a modified inner disk surface density gradient and some degree of dust depletion in the inner disk can explain the AA Ori's SED, from which we infer that the inner disk of AA Ori has evolved. We present that model configurations of a pre-transitional disk with a large gap extended to 60-80 AU in a settled dusty disk of a few hundred AU size with a high inclination angle (~60°) also create model SEDs close to the observed one. To distinguish whether the disk has a just-opened narrow gap or a large gap, with an altered surface density of the inner disk extended to 10 AU, we suggest a further investigation of AA Ori with high angular resolution observations.

• 토지주택연구
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• 제12권4호
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• pp.119-125
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• 2021

본 연구에서는 그리드를 이용한 철근콘크리트 휨부재의 연성보강 효과를 실험결과로 제시했다. 실험변수로는 비보강 철근콘크리트 휨부재(ORI), 바닥면 보강 철근콘크리트 휨부재(REB), 바닥 및 측면 보강 철근콘크리트 휨부재(REBS)가 있다. 실험은 4절점 휨 실험으로 수행되었다. 실험 결과, 보강을 통해 최대 휨강도가 17~20% 증가하였고, 측면 보강을 통해 휨 파괴 유도를 통한 연성보강 효과를 확인하였다. 또한, 연성지수를 계산하여 REB와 REBS의 연성지수가 ORI 대비 각각 2배, 3배 증가하였음을 확인하였다.

• BMB Reports
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• 제34권4호
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• pp.322-328
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• 2001

Excision and amplification of pre-determined, large genomic segments (taken directly from the genome of a natural host, which provides an alternative to conventional cloning in foreign vectors and hosts) was explored in human cells. In this approach, we devised a procedure for excising a large segment of human genomic DNA, the iNOS gene, by using the Cre/loxP system of bacteriophage P1 and amplifying the excised circles with the EBNA-1/oriP system of the Epstein-Barr virus. Two loxP sequences, each of which serves as a recognition site for recombinase Cre, were integrated unidirectionally into the 5'-UTR and 3'-UTR regions of the iNOS gene, together with an oriP sequence for conditional replication. The traps-acting genes cre and EBNA-1, which were under the control of a tetracycline responsive $P_{hcmv^*-1}$ promoter, were also inserted into the 5'-UTR and 3'-UTR regions of the iNOS gene, respectively, by homologous recombination. The strain carrying the inserted elements was stably maintained until the excision and amplification functions were triggered by the induction of cre and EBNA-1. Upon induction by doxycycline, Cre excised the iNOS gene that was flanked by two ZoxP sites and circularized it. The circularized iNOS gene was then amplified by the EBNA-1/oriP-system. With this procedure, approximately a 45.8-kb iNOS genomic fragment of human chromosome 17 was excised and successfully amplified in human cells. Our procedure can be used effectively for the sequencing of unclonable genes, the functional analysis of unknown genes, and gene therapy.

• 천문학회보
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• 제40권2호
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• pp.36.1-36.1
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• 2015

We present $5-14{\mu}m$ Infrared Spectrograph spectra of 14 T Tauri stars which show Polycyclic Aromatic Hydrocarbon (PAH) features and reside in 0.7 pc from ${\Theta}_1$ Ori C. The spectral types of nine out of 11 stars have spectral type information, with types ranging from K7-M5. These stars do not supply strong enough UV photons to excite PAH emission in their disks. Therefore, we consider the detection of PAH emission in disks around low mass stars illuminated by an external source of UV photons, namely, from Trapezium OB association, including ${\Theta}_1$ Ori C. The morphological features of PAH emission from most disks around K-M type host stars are unique, not belonging to any known classes of PAH features. We found that the PAH emission strengths decrease as the projected distance of the objects from ${\Theta}_1$ Ori C increase. We suggest future far-IR and submm/mm observations for better understanding of the characteristics and distribution of PAHs in these disks.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2003년도 한국우주과학회보 제12권2호
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• pp.24-24
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• 2003

We present preliminary results about the quasi-simultaneous near-infrared light curves of the long-period eclipsing polar V1309 Ori in the J, H, K', and K bands with almost complete orbital phase coverage using the CFHT-IR camera. The optical light curve in the V and R bands, obtained by 1.8m Telescope at BOAO, will be also presented. The shape and the amplitude of the orbital light curve change significantly from optical to near-infrared wavelengths.

• Journal of Microbiology
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• 제33권3호
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• pp.191-195
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• 1995

IciA protein has been shown as an inhibitor for the initiation of E. coli chromosomal DNA replication at oriC. IciA protein binds the AT-rich region in oriC and then blocks the initiation of chromosomal DNA replication. Two binding sites for IciA protein were identified in dnaA gene, encoding the initiator for the E. coli chromosomal replication, promoter region by gel-shift assay and DNase I footprinting, One, named as IciA site I, is located upstream of the dnaA promoter 1P. The other, named as IciA site II, is located downstream of the dnaA promoter 2P. The sequence comparison of the regions protected from the DNase I cleavage did not result in a clear consensus sequence for the binding of IciA protein, suggesting that IciA protein may be a member of multimeric complex dsDNA binding proteins. This study provided information about the binding mode of IciA protein. Even though the IciA site II and IciA binding site in oriC seem to be composed of two IciA binding units, one binding unit is likely enough to cause the binding of IciA protein to the IciA site I. The binding of IciA protein to the dna4 promoter implies that IciA protein may involve not only the control of the initiation of chromosomal DNA replication but also the control of the dna4 gene expression.

• 한국식품위생안전성학회지
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• 제38권6호
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• pp.442-448
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• 2023

본 연구는 황칠나무(Dendropanax morbiferus, DM)의 잎과 뿌리 추출물을 함유한 발효음료인 콤부차를 제조하고, 소재의 항산화 및 세포내 활성을 분석하였다. 홍차만으로 발효한 콤부차와 발효 과정에서 DM 잎이나 뿌리 추출물을 첨가한 홍차를 사용하여 발효한 콤부차의 pH 변화, 전체 산도, 라디칼 소거능을 비교하였다. 또한 RAW 264.7 세포주를 활용하여 DM의 잎이나 뿌리 추출물을 함유한 콤부차가 세포 내 산화질소(NO) 생성 및 염증 관련 사이토카인 함량에 미치는 영향을 평가하였다. DM 잎(BTKE-DML)과 뿌리(BTK-E-DMR)의 에탄올 추출물을 함유한 콤부차는 홍차만으로 제조한 콤부차(BTK-Ori)보다 발효 시작 3일 후 더 높은 라디칼 소거능을 나타내었다. RAW264.7 세포주를 이용한 in vitro 실험에서 세포독성을 고려하여 샘플을 8 mg/mL 콤부차로 처리한 결과, 지질다당류(LPS)로 유발된 NO 함량이 BTK-Ori 처리와 비교하였을 때 BTK-E-DML 및 BTK-E-DMR 처리에서 유의하게 감소하였다. 또한 LPS에 의해 자극되는 염증성 사이토카인인 인터루킨-6와 종양괴사인자-알파의 수준은 발효 15일 후 BTK-E-DML과 BTK-E-DMR을 처리한 세포에서 대조군에 비해 유의하게 감소하였다. 종합하면, 이러한 결과들은 DM의 잎 및 뿌리와 함께 발효된 콤부차는 항산화 활성이 증가되고, 세포 수준에서 염증 반응을 유의하게 조절할 수 있음을 입증하였다.

• TTA 저널
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• 통권146호
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• pp.82-84
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• 2013

• 오토저널
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• 제9권4호
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• pp.50-60
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• 1987

Combustion characteristics of opposed-jet-flames spouting out from dual prechambers of a divided combustion chamber were investigated by using high speed schilieren photography and chamber pressure measurement. Result shows that opposed-jet-flames are characterized by the parameter ( $A_{ori}$/ $V_{p}$) and there exists a certain critical value of ( $A_{ori}$/ $V_{p}$)c which distinguishes flame propagation patterns in the main chamber. Also higher chamber pressure and shorter total burning time can be derived by adopting this dual prechamber divided combustion chamber, which would lead a possibility of an appropriate combustion method of high load and low emissions.ons.ons.

• 천문학회보
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• 제38권1호
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• pp.54.2-54.2
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• 2013

FUors are believed in the outburst phase of the episodic accretion model with accretion mass rates enhanced by 2-3 orders of magnitude compared to the normal classical T-Tauri stars. We have been monitoring HBC 722, which was brightened by ~5 mag in the V band in 2010 and thus became a new FUor, with BOES. We also observed two other FUors, FU Ori and V1057 Cyg with BOES. V1057 Cyg has been monitored in the optical spectroscopy for decades since its outburst. We present the results of our 2-year monitoring observations of HBC 722 in comparison with FU Ori and V1057 Cyg.