• 천문학회지
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• 제56권1호
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• pp.35-40
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• 2023

We have been conducting a exoplanet search survey using Bohyunsan Observatory Echelle Spectrograph (BOES) for the last 18 years. We present the detection of exoplanet candidate in orbit around HD 18438 from high-precision radial velocity (RV) mesurements. The target was already reported in 2018 (Bang et al. 2018). They conclude that the RV variations with a period of 719 days are likely to be caused by the pulsations because the Lomb-Scargle periodogram of HIPPARCOS photometric and H_α EW variations for HD 18438 show peaks with periods close to that of RV variations and there were no correlations between bisectors and RV measurements. However, the data were not sufficient to reach a firm conclusion. We obtained more RV data for four years. The longer time baseline yields a more accurate determination with a revised period of 803 ± 5 days and the planetary origin of RV variations with a minimum planetary companion mass of 21 ± 1 M_Jup. Our current estimate of the stellar parameters for HD 18438 makes it currently the largest star with a planetary companion.

• Korean Circulation Journal
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• 제54권4호
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• pp.203-217
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• 2024

Background and Objective: The effects of radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) on right ventricular (RV) function are not well known. Methods: Patients who underwent RFCA for AF and underwent pre- and post-procedural echocardiography were enrolled consecutively. Fractional area change (FAC), RV free-wall longitudinal strain (RVFWSL), and RV 4-chamber strain including the ventricular septum (RV4CSL) were measured. Changes in FAC, RVFWSL, and RV4CSL before and after RFCA were compared among paroxysmal AF (PAF), persistent AF (PeAF), and long-standing persistent AF (LSPeAF) groups. Results: A total of 164 participants (74 PAF, 47 PeAF, and 43 LSPeAF; age, 60.8 ± 9.8 years; men, 74.4%) was enrolled. The patients with PeAF and LSPeAF had worse RV4CSL (p<0.001) and RVFWSL (p<0.001) than those with PAF and reference values. Improvements in RVFWSL and RV4CSL after RFCA were significant in the PeAF group compared with the PAF and LSPeAF groups (ΔRV4CSL, 8.4% [5.1, 11.6] in PeAF vs. 1.0% [-1.0, 4.1] in PAF, 1.9% [-0.2, 4.4] in LSPeAF, p<0.001; ΔRVFWSL, 9.0% [6.9, 11.5] in PeAF vs. 0.9% [-1.4, 4.9] in PAF, 1.0% [-1.0, 3.6] in LSPeAF, p<0.001). In patients without recurrence, improvements in RVFWSL and RV4CSL after RFCA were significant in the PeAF group compared to the LSPeAF group. Conclusions: RV systolic function is more impaired in patients with PeAF and LSPeAF than in those with PAF. RV systolic function is more improved after RFCA in patients with PeAF than in those with PAF or LSPeAF.

• Clinical and Experimental Pediatrics
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• 제60권9호
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• pp.296-301
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• 2017

Purpose: The aim of this study was to evaluate whether infants with rhinovirus (RV) infection-induced wheezing and those with respiratory syncytial virus (RSV) infection-induced wheezing have different cytokine profiles in the acute stage. Methods: Of the infants with lower respiratory tract infection (LRTI) between September 2011 and May 2012, 88 were confirmed using reverse transcription polymerase chain reaction and hospitalized. Systemic interferon-gamma ($IFN-{\gamma}$), interleukin (IL)-2, IL-12, IL-4, IL-5, IL-13, and Treg-type cytokine (IL-10) responses were examined with multiplex assay using acute phase serum samples. Results: Of the 88 patients, 38 had an RV infection (RV group) and 50 had an RSV infection (RSV group). In the RV group, the $IFN-{\gamma}$ and IL-10 concentrations were higher in the patients with than in the patients without wheezing (P=0.022 and P=0.007, respectively). In the RSV group, the differences in $IFN-{\gamma}$ and IL-10 concentrations did not reach statistical significance between the patients with and the patients without wheezing (P=0.105 and P=0.965, respectively). The $IFN-{\gamma}$ and IL-10 concentrations were not significantly different between the RV group with wheezing and the RSV group with wheezing (P=0.155 and P=0.801, respectively), in contrast to the significant difference between the RV group without wheezing and the RSV group without wheezing (P=0.019 and P=0.035, respectively). Conclusion: In comparison with RSV-induced LRTI, RV-induced LRTI combined with wheezing showed similar $IFN-{\gamma}$ and IL-10 levels, which may have an important regulatory function.

• Journal of Microbiology and Biotechnology
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• 제28권3호
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• pp.391-396
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• 2018

It is well known that Korean red ginseng has various biological activities. However, there is little knowledge about the antiviral activity of Korean red ginseng and its ginsenosides. In this study, we addressed whether oral administration of ginsenoside-Rb2 and -Rg3 is able to protect against rotavirus (RV) infection. The protective effect of ginsenosides against RV infection was examined using an in vivo experiment model in which newborn mice (10-day-old) were inoculated perorally (p.o.) with $1.5{\times}10^6$ plaque-forming units/mouse of RV strain SA11. When various dosages of ginsenoside-Rb2 (25-250 mg/kg) were administered 3days, 2 days, or 1 day before virus challenge, treatment with this ginsenoside at the dosage of 75 mg/kg 3days before virus infection most effectively reduced RV-induced diarrhea. In addition, consecutive administration of ginsenoside-Rb2 (75 mg/kg) at 3 days, 2 days, and 1 day before virus infection was more effective than single administration on day -3. The consecutive administration of ginsenoside-Rb2 also reduced virus titers in the bowels of RV-infected mice. In an experiment to compare the protective activity between ginsenoside-Rb2 and its two hydrolytic products (20(S)- and 20(R)-ginsenoside-Rg3), 20(S)-ginsenoside-Rg3, but not 20(R)-ginsenoside-Rg3, prevented RV infection. These results suggest that ginsenoside-Rb2 and its hydrolytic product, 20(S)-ginsenoside-Rg3, are promising candidates as an antiviral agent to protect against RV infection.

• 한국전자파학회논문지
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• 제25권10호
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• pp.1062-1068
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• 2014

본 논문에서는 두 개의 순차적인 inverse synthetic aperture radar(ISAR) 영상들을 활용하여 표적의 회전 속도(Rotation Velocity: RV) 추정을 통한 수직 거리 스케일링(cross-range scaling: CRS)을 수행한다. 순차적으로 형성된 두 개의 ISAR 영상들에 각각 scale invariant feature transform(SIFT)를 적용함으로써 관측각도의 변화에 강인한 산란원(scatterer)들을 추출한다. 추출된 산란원과 각 영상 내 표적의 회전 중심(Rotation Center: RC) 사이의 거리가 같다는 점을 이용하여 비용함수(cost function)를 설정한 후, 전역 탐색 기법(exhaustive search method)과 결합된 particle swarm optimization(PSO)의 최적화를 통해 표적의 RV를 RC 정보 없이 추정한다. 시뮬레이션에서는 시나리오 기반으로 기동하는 표적에 대한 ISAR 영상 형성 후, 제안된 기법을 통해 RC의 정보 없이 RV를 추정함으로써 ISAR 영상의 CRS가 성공적으로 수행됨을 보여준다.

• Korean Journal of Radiology
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• 제21권4호
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• pp.450-461
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• 2020

Objective: We performed a meta-analysis to evaluate the agreement of cardiac computed tomography (CT) with cardiac magnetic resonance imaging (CMRI) in the assessment of right ventricle (RV) volume and functional parameters. Materials and Methods: PubMed, EMBASE, and Cochrane library were systematically searched for studies that compared CT with CMRI as the reference standard for measurement of the following RV parameters: end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), or ejection fraction (EF). Meta-analytic methods were utilized to determine the pooled weighted bias, limits of agreement (LOA), and correlation coefficient (r) between CT and CMRI. Heterogeneity was also assessed. Subgroup analyses were performed based on the probable factors affecting measurement of RV volume: CT contrast protocol, number of CT slices, CT reconstruction interval, CT volumetry, and segmentation methods. Results: A total of 766 patients from 20 studies were included. Pooled bias and LOA were 3.1 mL (-5.7 to 11.8 mL), 3.6 mL (-4.0 to 11.2 mL), -0.4 mL (5.7 to 5.0 mL), and -1.8% (-5.7 to 2.2%) for EDV, ESV, SV, and EF, respectively. Pooled correlation coefficients were very strong for the RV parameters (r = 0.87-0.93). Heterogeneity was observed in the studies (I² > 50%, p < 0.1). In the subgroup analysis, an RV-dedicated contrast protocol, ≥ 64 CT slices, CT volumetry with the Simpson's method, and inclusion of the papillary muscle and trabeculation had a lower pooled bias and narrower LOA. Conclusion: Cardiac CT accurately measures RV volume and function, with an acceptable range of bias and LOA and strong correlation with CMRI findings. The RV-dedicated CT contrast protocol, ≥ 64 CT slices, and use of the same CT volumetry method as CMRI can improve agreement with CMRI.

• Pediatric Infection and Vaccine
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• 제26권2호
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• pp.99-111
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• 2019

목적: 호흡기세포융합바이러스(RSV)와 라이노바이러스(hRV)는 소아의 호흡기 바이러스감염의 가장 흔한 원인이다. 본 연구는 RSV 혹은 hRV 감염으로 입원하는 소아의 역학, 임상적 특성, 혈액 검사 결과를 분석하고, 각 바이러스 단독 감염과 동시 감염 간의 임상적 특성 및 혈액 검사 결과를 비교하고자 하였다. 방법: 2014년 10월부터 2017년 4월까지 매년 10월부터 4월 사이에 원주세브란스기독병원 소아청소년과에 호흡기 증상으로 입원한 만 5세 미만의 환아 중, 비강인두도말 검체로 다중 역전사 실시간 중합효소연쇄반응 검사를 시행하여 RSV 혹은 hRV가 검출된 사례를 대상으로 의무기록을 후향적으로 분석하였다. 결과: 강원 지역 소아 호흡기 환자의 multiplex RT-PCR 바이러스 검출 패턴 상, RSV는 늦가을부터 초봄 사이, hRV는 연중 고르게 분포하였다. RSV 혹은 hRV가 검출된 총 384례 중 RSV는 258례(R group), hRV는 99례(H group)에서 단독으로 검출되었고, RSV와 hRV의 동시 검출은 27례에서 있었다(RH group). R군의 연령 중앙값은 6개월이었으며, 248례(96.1%)가 하기도 감염이었다. 산소치료는 14례(5.4%)에서 있었다. 12개월 미만의 영아가 반수 이상을 차지하였고(63.2%) 호흡곤란, 산소치료가 많았다. H군의 연령 중앙값은 16개월이었으며, 56례(56.6%)가 하기도 감염이었다. 산소치료는 4례(4.0%), 기계 호흡은 1례(1.0%)에서 시행하였다. 영아(40.4%)는 12개월 이상 환자보다 재원기간이 길었다(5 vs. 4 days, P<0.05). RH군의 경우 24례(88.9%)가 하기도 감염이었고, 산소치료는 2례(7.4%)에서 있었다. RH군은 R군 및 H군과 비교하여 재원기간, 산소치료 및 기계 호흡의 비율에 차이가 없어, 동시 감염과 단독 감염의 유의한 중증도 차이는 없는 것으로 나타났다. 결론: RSV는 hRV보다 더 어린 연령에서 잘 이환되고 하기도 감염의 비율이 높았다. 동시 감염된 환자의 임상증상은 RSV 감염의 특성이 보다 반영되었고, 단독 감염에 비해 중증도에 차이는 없었다.

• 한국식품영양학회지
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• 제30권6호
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• pp.1348-1358
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• 2017

To enhance the physiological activity of the Rhynchosia volubilis (RV), R. volubilis (RVHE-A) and R. volubilis-added herbal powder (RVHE-B) were fermented with a solid state culture of Hericium erinaceum mycelia (HE). The total isoflavone contents of the non-fermented RV-A ($489.9{\mu}g/g$) and RV-B ($571.1{\mu}g/g$) were remarkably increased in fermented RVHE-A ($1,836.4{\mu}g/g$) and RVHE-B ($1,276.7{\mu}g/g$). In particular, aglycone isoflavones such as daidzein and genistein were significantly higher in the RVHE-A than any other sample. When hot-water (HW) and EtOH extracts (E) were fractionated from the RV and RVHE, both extracts from the RVHE-A were higher than those from the RV-A in total polyphenol and flavonoid contents. However, the RVHE-B-HW showed a lower polyphenol and flavonoid content level than did RV-B-HW. RVHE-A-HW and -E also had more potent ABTS radical scavenging activity than any extract from the non-fermented RV and other ferments (RVHE-B). In the meanwhile, RVHE-A-HW potently stimulated the production of macrophage activation-related cytokines such as $TNF-{\alpha}$, IL-6 and IL-12 ($841.7{\pm}71.3pg/mL$, $3.9{\pm}0.1ng/mL$, $179.3{\pm}30.2pg/mL$) from peritoneal macrophage more than RV-A-HW ($92.5{\pm}1.5pg/mL$, $0.1{\pm}0.0ng/mL$, $37.4{\pm}5.4pg/mL$) as well as RVHE-B-HW ($557.0{\pm}21.3pg/mL$, $1.8{\pm}0.0ng/mL$, $90.0{\pm}10.0pg/mL$). However, all the EtOH extracts did not show significant activity. In addition, the RVHE-A-HW showed a significantly higher intestinal immune system modulating activity through Peyer's patch and GM-CSF production than did any other extract from RV and RVHE-B. In conclusion, these results suggest that the fermented R. volubilis with H. erinaceum mycelia possesses a possible use as an industrial application as functional food or material.

• 천문학회지
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• 제51권1호
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• pp.17-25
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• 2018

Detecting exoplanets around giant stars sheds light on the later-stage evolution of planetary systems. We observed the M giant HD 18438 and the K giant HD 158996 as part of a Search for Exoplanets around Northern circumpolar Stars (SENS) and obtained 38 and 24 spectra from 2010 to 2017 using the high-resolution Bohyunsan Observatory Echelle Spectrograph (BOES) at the 1.8m telescope of Bohyunsan Optical Astronomy Observatory in Korea. We obtained precise RV measurements from the spectra and found long-period radial velocity (RV) variations with period 719.0 days for HD 18438 and 820.2 days for HD 158996. We checked the chromospheric activities using Ca $\text\tiny{II}$ H and $H{\alpha}$ lines, HIPPARCOS photometry and line bisectors to identify the origin of the observed RV variations. In the case of HD 18438, we conclude that the observed RV variations with period 719.0 days are likely to be caused by the pulsations because the periods of HIPPARCOS photometric and $H{\alpha}$ EW variations for HD 18438 are similar to that of RV variations in Lomb-Scargle periodogram, and there are no correlations between bisectors and RV measurements. In the case of HD 158996, on the other hand, we did not find any similarity in the respective periodograms nor any correlation between RV variations and line bisector variations. In addition, the probability that the real rotational period can be as longer than the RV period for HD 158996 is only about 4.3%. Thus we conclude that observed RV variations with a period of 820.2 days of HD 158996 are caused by a planetary companion, which has the minimum mass of 14.0 $M_{Jup}$, the semi-major axis of 2.1 AU, and eccentricity of 0.13 assuming the stellar mass of $1.8 M_{\odot}$. HD 158996 is so far one of the brightest and largest stars to harbor an exoplanet candidate.

• Korean Journal of Radiology
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• 제20권6호
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• pp.956-966
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• 2019

Objective: To characterize the changes in right ventricular (RV) volume, volume load, and function measured with cardiac computed tomography (CT) over the entire time course of tetralogy of Fallot (TOF). Materials and Methods: In 374 patients with TOF, the ventricular volume, ventricular function, and RV volume load were measured with cardiac CT preoperatively (stage 1), after palliative operation (stage 2), after total surgical repair (stage 3), or after pulmonary valve replacement (PVR) (stage 4). The CT-measured variables were compared among the four stages. After total surgical repair, the postoperative duration (POD) and the CT-measured variables were correlated with each other. In addition, the demographic and CT-measured variables in the early postoperative groups were compared with those in the late postoperative and the preoperative group. Results: Significantly different CT-based measures were found between stages 1 and 3 (indexed RV end-diastolic volume [EDV], 63.6 ± 15.2 mL/m² vs. 147.0 ± 38.5 mL/m² and indexed stroke volume (SV) difference, 7.7 ± 10.3 mL/m² vs. 32.2 ± 16.4 mL/m²; p < 0.001), and between stages 2 and 3 (indexed RV EDV, 72.4 ± 19.7 mL/m² vs. 147.0 ± 38.5 mL/m² and indexed SV difference, 5.7 ± 13.1 mL/m² vs. 32.2 ± 16.4 mL/m²; p < 0.001). After PVR, the effect of RV volume load (i.e., indexed SV difference) was reduced from 32.2 mL/m² to 1.7 mL/m². Positive (0.2 to 0.8) or negative (-0.2 to -0.4) correlations were found among the CT-based measures except between the RV ejection fraction (EF) and the RV volume load parameters. With increasing POD, an early rapid increase was followed by a slow increase and a plateau in the indexed ventricular volumes and the RV volume load parameters. Compared with the preoperative data, larger ventricular volumes and lower EFs were observed in the early postoperative period. Conclusion: Cardiac CT can be used to characterize RV volume, volume load, and function over the entire time course of TOF.