CHARACTERIZING THE TIME-FREQUENCY PROPERTIES OF THE 4 Hz QUASI-PERIODIC OSCILLATION AROUND THE BLACK HOLE X-ray BINARY XTE J1550-564

SU, YI-HAO,CHOU, YI,HU, CHIN-PING,YANG, TING-CHANG,HSIEH, HUNG-EN,CHUANG, PO-SHENG,LIN, CHING-PING,LIAO, NAI-HUI The Korean Astronomical Society 2015 天文學論叢 Vol.30 No.2

We present the results from analysis of the Hilbert-Huang transform (HHT) for the 4 Hz quasi-periodic oscillations (QPO) around the black hole X-ray binary XTE J1550-564. The resultant Hilbert spectra demonstrate that the QPO is composed of a series of intermittent signals appearing occasionally. From the analysis of the HHT, we further found the distribution of the lifetimes for the intermittent oscillations and the distribution for the time intervals with no significant signal (the break time). The mean lifetime is 1.45 s and 90% of the oscillation segments have lifetimes less than 3.1 s whereas the mean break time is 0.42 s and 90% of break times are less than 0.73 s. We conclude that the intermittent feature of the QPO could be explained by the Lense-Thirring precession model and rules out interpretations of continual frequency modulation.

An Application of Hilbert-Huang Transform on the Non-Stationary Astronomical Time Series: The Superorbital Modulation of SMC X-1

Chin-Ping Hu,Yi Chou,Ming-Chya Wu,Ting-Chang Yang,Yi-Hao Su 한국우주과학회 2013 Journal of Astronomy and Space Sciences Vol.30 No.2

We present the Hilbert-Huang transform (HHT) analysis on the quasi-periodic modulation of SMC X-1. SMC X-1, consisting of a neutron star and a massive companion, exhibits superorbital modulation with a period varying between ~40 d and ~65 d. We applied the HHT on the light curve observed by the All-Sky Monitor onboard Rossi X-ray Timing Explorer (RXTE) to obtain the instantaneous frequency of the superorbital modulation of SMC X-1. The resultant Hilbert spectrum is consistent with the dynamic power spectrum while it shows more detailed information in both the time and frequency domains. According to the instantaneous frequency, we found a correlation between the superorbital period and the modulation amplitude. Combining the spectral observation made by the Proportional Counter Array onboard RXTE and the superorbital phase derived in the HHT, we performed a superorbital phase-resolved spectral analysis of SMC X-1. An analysis of the spectral parameters versus the orbital phase for different superorbital states revealed that the diversity of nH has an orbital dependence. Furthermore,we obtained the variation in the eclipse profiles by folding the All Sky Monitor light curve with orbital period for different superorbital states. A dip feature, similar to the pre-eclipse dip of Her X-1, can be observed only in the superorbital ascending and descending states, while the width is anti-correlated with the X-ray flux.

Absence of EZH2 Gene Mutation in Chronic Myeloid Leukemia Patients in Blast Crisis

Chen, Hao-Yue,Yao, Hong,Wu, Ling-Yu,Liu, Can-Jun,Zhu, Jian-Qin,Liu, Chun-Hua,Wang, Wei,Dong, Sha-Sha,Ping, Na-Na,Chen, Su-Ning,Sun, Miao Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.5

APPLICATIONS OF THE HILBERT-HUANG TRANSFORM ON THE NON-STATIONARY ASTRONOMICAL TIME SERIES

HU, CHIN-PING,CHOU, YI,YANG, TING-CHANG,SU, YI-HAO,HSIEH, HUNG-EN,LIN, CHING-PING,CHUANG, PO-SHENG,LIAO, NAI-HUI The Korean Astronomical Society 2015 天文學論叢 Vol.30 No.2

The development of time-frequency analysis techniques allow astronomers to successfully deal with the non-stationary time series that originate from unstable physical mechanisms. We applied a recently developed time-frequency analysis method, the Hilbert-Huang transform (HHT), to two non-stationary phenomena: the superorbital modulation in the high-mass X-ray binary SMC X-1 and the quasi-periodic oscillation (QPO) of the AGN RE J1034+396. From the analysis of SMC X-1, we obtained a Hilbert spectrum that shows more detailed information in both the time and frequency domains. Then, a phase-resolved analysis of both the spectra and the orbital profiles was presented. From the spectral analysis, we noticed that the iron line production is dominated by different regions of this binary system in different superorbital phases. Furthermore, a pre-eclipse dip lying at orbital phase ~0:6-0:85 was discovered during the superorbital transition state. We further applied the HHT to analyze the QPO of RE J1034+396. From the Hilbert spectrum and the O-C analysis results, we suggest that it is better to divide the evolution of the QPO into three epochs according to their different periodicities. The correlations between the QPO periods and corresponding fluxes were also different in these three epochs. The change in periodicity and the relationships could be interpreted as the change in oscillation mode based on the diskoseismology model.

ON THE COMPLEX VARIABILITY OF THE SUPERORBITAL MODULATION PERIOD OF LMC X-4

HU, CHIN-PING,LIN, CHING-PING,CHOU, YI,YANG, TING-CHANG,SU, YI-HAO,HSIEH, HUNG-EN,CHUANG, PO-SHENG,LIAO, NAI-HUI The Korean Astronomical Society 2015 天文學論叢 Vol.30 No.2

LMC X-4 is an eclipsing high-mass X-ray binary exhibiting a superorbital modulation with a period of ~ 30:5 days. We present a detailed study of the variations of the superorbital modulation period with a time baseline of ~ 18 years. The period determined in the light curve collected by the Monitor of All-sky X-ray Image (MAXI) significantly deviates from that observed by the All Sky Monitor (ASM) onboard the Rossi X-ray Timing Explorer (RXTE). Using the data collected by RXTE/ASM, MAXI, and the Burst Alert Telescope (BAT) onboard Swift, we found a significant period derivative, $\dot{P}=(2.08{\pm}0.12){\times}10^{-5}$. Furthermore, the O{C residual shows complex short-term variations indicating that the superorbital modulation of LMC X-4 exhibits complicated unstable behaviors. In addition, we used archive data collected by the Proportional Counter Array (PCA) on RXTE to estimate the orbital and spin parameters. The detected pulse frequencies obtained in small time segments were fitted with a circular orbital Doppler shift model. In addition to orbital parameters and spin frequency for each observation, we found a spin frequency derivative of $\dot{v}=(6.482{\pm}0.011){\times}10^{-13}Hz{\cdot}s^{-1}$. More precise orbital and spin parameters will be evaluated by the pulse arrival time delay technique in the future.

An Application of Hilbert-Huang Transform on the Non-Stationary Astronomical Time Series: The Superorbital Modulation of SMC X-1

Hu, Chin-Ping,Chou, Yi,Wu, Ming-Chya,Yang, Ting-Chang,Su, Yi-Hao 한국우주과학회 2013 Journal of Astronomy and Space Sciences Vol.30 No.2

We present the Hilbert-Huang transform (HHT) analysis on the quasi-periodic modulation of SMC X-1. SMC X-1, consistingof a neutron star and a massive companion, exhibits superorbital modulation with a period varying between ~40 d and ~65 d.We applied the HHT on the light curve observed by the All-Sky Monitor onboard Rossi X-ray Timing Explorer (RXTE) to obtainthe instantaneous frequency of the superorbital modulation of SMC X-1. The resultant Hilbert spectrum is consistent with thedynamic power spectrum while it shows more detailed information in both the time and frequency domains. According to theinstantaneous frequency, we found a correlation between the superorbital period and the modulation amplitude. Combiningthe spectral observation made by the Proportional Counter Array onboard RXTE and the superorbital phase derived in theHHT, we performed a superorbital phase-resolved spectral analysis of SMC X-1. An analysis of the spectral parameters versusthe orbital phase for different superorbital states revealed that the diversity of nH has an orbital dependence. Furthermore,we obtained the variation in the eclipse profiles by folding the All Sky Monitor light curve with orbital period for differentsuperorbital states. A dip feature, similar to the pre-eclipse dip of Her X-1, can be observed only in the superorbital ascendingand descending states, while the width is anti-correlated with the X-ray flux.

Clinicopathologic Characteristics and Prognoses for Multicentric Occurrence and Intrahepatic Metastasis in Synchronous Multinodular Hepatocellular Carcinoma Patients

Li, Shi-Lai,Su, Ming,Peng, Tao,Xiao, Kai-Yin,Shang, Li-Ming,Xu, Bang-Hao,Su, Zhi-Xiong,Ye, Xin-Ping,Peng, Ning,Qin, Quan-Lin,Chen, De-Feng,Chen, Jie,Li, Le-Qun Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.1

Background: Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, and the outcomes for patients are still poor. It is important to determine the original type of synchronous multinodular HCC for preoperative assessment and the choice of treatment therapy as well as for the prediction of prognosis after treatment. Aims: To analyze clinicopathologic characteristics and prognoses in patients with multicentric occurrence (MO) and intrahepatic metastasis (IM) of synchronous multinodular hepatocellular carcinoma (HCC). Methods: The study group comprised 42 multinodular HCC patients with a total of 112 nodules. The control group comprised 20 HCC patients with 16 single nodular HCC cases and 4 HCC cases with a portal vein tumor emboli. The mitochondrial DNA (mtDNA) D-loop region was sequenced, and the patients of the study group were categorized as MO or IM based on the sequence variations. Univariate and multivariate analyses were used to determine the important clinicopathologic characteristics in the two groups. Results: In the study group, 20 cases were categorized as MO, and 22 as IM, whereas all 20 cases in the control group were characterized as IM. Several factors significantly differed between the IM and MO patients, including hepatitis B e antigen (HBeAg), cumulative tumor size, tumor nodule location, cirrhosis, portal vein and/or microvascular tumor embolus and the histological grade of the primary nodule. Multivariate analysis further demonstrated that cirrhosis and portal vein and/or microvascular tumor thrombus were independent factors differentiating between IM and MO patients. The tumor-free survival time of the MO subjects was significantly longer than that of the IM subjects ($25.7{\pm}4.8$ months vs. $8.9{\pm}3.1$ months, p=0.017). Similarly, the overall survival time of the MO subjects was longer ($31.6{\pm}5.3$ months vs. $15.4{\pm}3.4$ months, p=0.024). The multivariate analysis further demonstrated that the original type (p=0.035) and Child-Pugh grade (p<0.001) were independent predictors of tumor-free survival time. Cirrhosis (p=0.011), original type (p=0.034) and Child-Pugh grade (p<0.001) were independent predictors of overall survival time. Conclusions: HBeAg, cumulative tumor size, tumor nodule location, cirrhosis, portal vein and/or microvascular tumor embolus and histological grade of the primary nodule are important factors for differentiating IM and MO. MO HCC patients might have a favorable outcome compared with IM patients.

Endovascular Treatment for Iliac Vein Compression Syndrome: a Comparison between the Presence and Absence of Secondary Thrombosis

Wen-Sheng Lou,Jian-Ping Gu,Xu He,Liang Chen,Hao-Bo Su,Guo-Ping Chen,Jing-Hua Song,Tao Wang 대한영상의학회 2009 Korean Journal of Radiology Vol.10 No.2

Objective: To evaluate the value of early identification and endovascular treatment of iliac vein compression syndrome (IVCS), with or without deep vein thrombosis (DVT). Materials and Methods: Three groups of patients, IVCS without DVT (group 1, n = 39), IVCS with fresh thrombosis (group 2, n = 52) and IVCS with non-fresh thrombosis (group 3, n = 34) were detected by Doppler ultrasonography, magnetic resonance venography, computed tomography or venography. The fresh venous thrombosis were treated by aspiration and thrombectomy, whereas the iliac vein compression per se were treated with a self-expandable stent. In cases with fresh thrombus, the inferior vena cava filter was inserted before the thrombosis suction, mechanical thrombus ablation, percutaneous transluminal angioplasty, stenting or transcatheter thrombolysis. Results: Stenting was performed in 111 patients (38 of 39 group 1 patients and 73 of 86 group 2 or 3 patients). The stenting was tried in one of group 1 and in three of group 2 or 3 patients only to fail. The initial patency rates were 95% (group 1), 89% (group 2) and 65% (group 3), respectively and were significantly different (p = 0.001). Further, the six month patency rates were 93% (group 1), 83% (group 2) and 50% (group 3), respectively, and were similarly significantly different (p = 0.001). Both the initial and six month patency rates in the IVCS patients (without thrombosis or with fresh thrombosis), were significantly greater than the patency rates of IVCS patients with non-fresh thrombosis. Conclusion: From the cases examined, the study suggests that endovascular treatment of IVCS, with or without thrombosis, is effective. Objective: To evaluate the value of early identification and endovascular treatment of iliac vein compression syndrome (IVCS), with or without deep vein thrombosis (DVT). Materials and Methods: Three groups of patients, IVCS without DVT (group 1, n = 39), IVCS with fresh thrombosis (group 2, n = 52) and IVCS with non-fresh thrombosis (group 3, n = 34) were detected by Doppler ultrasonography, magnetic resonance venography, computed tomography or venography. The fresh venous thrombosis were treated by aspiration and thrombectomy, whereas the iliac vein compression per se were treated with a self-expandable stent. In cases with fresh thrombus, the inferior vena cava filter was inserted before the thrombosis suction, mechanical thrombus ablation, percutaneous transluminal angioplasty, stenting or transcatheter thrombolysis. Results: Stenting was performed in 111 patients (38 of 39 group 1 patients and 73 of 86 group 2 or 3 patients). The stenting was tried in one of group 1 and in three of group 2 or 3 patients only to fail. The initial patency rates were 95% (group 1), 89% (group 2) and 65% (group 3), respectively and were significantly different (p = 0.001). Further, the six month patency rates were 93% (group 1), 83% (group 2) and 50% (group 3), respectively, and were similarly significantly different (p = 0.001). Both the initial and six month patency rates in the IVCS patients (without thrombosis or with fresh thrombosis), were significantly greater than the patency rates of IVCS patients with non-fresh thrombosis. Conclusion: From the cases examined, the study suggests that endovascular treatment of IVCS, with or without thrombosis, is effective.

Initial Factors Influencing Duration of Hospital Stay in Adult Patients With Peritonsillar Abscess

Yu-Hsi Liu,Hsing-Hao Su,Yi-Wen Tsai,Yu-Yi Hou,Kuo-Ping Chang,Chao-Chuan Chi,Ming-Yee Lin,Pi-Hsiung Wu 대한이비인후과학회 2017 Clinical and Experimental Otorhinolaryngology Vol.10 No.1

Objectives. To review cases of peritonsillar abscess and investigate the initial clinical factors that may influence the duration of hospitalization. To determine the predictive factors of prolonged hospital stay in adult patients with peritonsillar abscess. Methods. Subjects were adults hospitalized with peritonsillar abscess. We retrospectively reviewed 377 medical records from 1990 to 2013 in a tertiary medical center in southern Taiwan. The association between clinical characteristics and the length of hospital stay was analyzed with independent t-test, univariate linear regression and multiple linear regression analysis. Results. The mean duration of hospitalization was 6.2±6.0 days. With univariate linear regression, a prolonged hospital stay was associated with several variables, including female gender, older ages, nonsmoking status, diabetes mellitus, hypertension, band forms in white blood cell (WBC) counts, and lower hemoglobin levels. With multiple linear regression analysis, four independent predictors of hospital stay were noted: years of age (P<0.001), history of diabetes mellitus (P<0.001), ratio of band form WBC (P<0.001), and hemoglobin levels (P<0.001). Conclusion. In adult patients with peritonsillar abscess, older ages, history of diabetes mellitus, band forms in WBC counts and lower hemoglobin levels were independent predictors of longer hospitalization.

THE ORBITAL EPHEMERIS OF THE PARTIAL ECLIPSING X-ray BINARY X1822-371

HSIEH, HUNG-EN,CHOU, YI,HU, CHIN-PING,YANG, TING-CHANG,SU, YI-HAO,LIN, CHING-PING,CHUANG, PO-SHENG,LIAO, NAI-HUI The Korean Astronomical Society 2015 天文學論叢 Vol.30 No.2

X1822-371 is a low mass X-ray binary with an accretion disk corona exhibiting partial eclipses and pulsations in the X-ray band. We update its orbital ephemeris by combining new RXTE observations and historical records, with a total time span of 34 years. There were 11 RXTE observations in 2011 but the eclipsing profile can be seen in only 4 of them. The eclipsing center times were obtained by fitting the profile with the same model as previous studies. Combined with the eclipsing center times reported by Iaria et al. (2011), the O-C analysis was processed. A quadratic model was applied to fit the O-C results and produced a mean orbital period derivative of $\dot{P}_{orb}=1.339(25){\times}10^{-10}s/s$, which is slightly smaller than previous records. In addition to the orbital modulation from the orbital profile, we also present our preliminary results for measuring the orbital parameters using the orbital Doppler effect from the pulsation of the neutron star in X1822-371. The updated orbital parameters from eclipsing profiles will be further compared with the ones from pulsar timing.