Epidemiology, Characteristics, and Prognostic Factors of Primary Atypical Teratoid/Rhabdoid Tumors in the Spinal Canal: A Systematic Review

Zhibin Li,Yubo Wang,Liyan Zhao,Yunqian Li 대한척추신경외과학회 2024 Neurospine Vol.21 No.1

Primary atypical teratoid/rhabdoid tumors (AT/RTs) in the spinal canal are rare central nervous system (CNS) neoplasms that are challenging to diagnose and treat. To date, there has been no standard treatment regimen for these challenging malignant tumors. Thus, we conducted this research to explore potential prognostic factors and feasible treatment modalities for improving the prognosis of these tumors. Articles were retrieved from the PubMed, MEDLINE, and Embase databases, using the keywords “atypical teratoid/rhabdoid tumor,” “rhabdoid tumor,” “spine,” “spinal,” “spinal neoplasm”, and “spinal cord neoplasm.” All eligible cases demonstrated SMARCB1-deficient expression validated by pathological examination. We collected and analyzed data related to clinical presentation, radiological features, pathological characteristics, treatment modalities and prognosis via Kaplan-Meier and Cox regression analyses. Thirty-six articles comprising 58 spinal AT/RT patients were included in the study. The median progression-free survival (PFS) and overall survival (OS) were 18 and 22 months, respectively. Kaplan-Meier analysis demonstrated significant survival improvements for OS in the nonmetastasis, male, radiotherapy and intrathecal chemotherapy groups as well as for PFS in the chemotherapy and radiotherapy groups. Multivariate analysis revealed that chemotherapy and radiotherapy were prognostic factors for improved PFS, and that intrathecal chemotherapy reduced the risk of mortality. Spinal AT/RTs are uncommon malignant entities with a dismal survival rate. Although our review is limited by variability between cases, there is some evidence revealing potential risk factors and the importance of systematic chemotherapy, intrathecal chemotherapy and radiotherapy in spinal AT/RT treatment modalities.

Combinatorial patterns of histone acetylations and methylations in the human genome

Wang, Zhibin,Zang, Chongzhi,Rosenfeld, Jeffrey A,Schones, Dustin E,Barski, Artem,Cuddapah, Suresh,Cui, Kairong,Roh, Tae-Young,Peng, Weiqun,Zhang, Michael Q,Zhao, Keji Nature Publishing Group 2008 Nature genetics Vol.40 No.7

Histones are characterized by numerous posttranslational modifications that influence gene transcription. However, because of the lack of global distribution data in higher eukaryotic systems, the extent to which gene-specific combinatorial patterns of histone modifications exist remains to be determined. Here, we report the patterns derived from the analysis of 39 histone modifications in human CD4<SUP>+</SUP> T cells. Our data indicate that a large number of patterns are associated with promoters and enhancers. In particular, we identify a common modification module consisting of 17 modifications detected at 3,286 promoters. These modifications tend to colocalize in the genome and correlate with each other at an individual nucleosome level. Genes associated with this module tend to have higher expression, and addition of more modifications to this module is associated with further increased expression. Our data suggest that these histone modifications may act cooperatively to prepare chromatin for transcriptional activation.

Analysis of Switching Clamped Oscillations of SiC MOSFETs

Ke, Junji,Zhao, Zhibin,Xie, Zongkui,Wei, Changjun,Cui, Xiang The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.3

SiC MOSFETs have been used to improve system efficiency in high frequency converters due to their extremely high switching speed. However, this can result in undesirable parasitic oscillations in practical systems. In this paper, models of the key components are introduced first. Then, theoretical formulas are derived to calculate the switching oscillation frequencies after full turn-on and turn-off in clamped inductive circuits. Analysis indicates that the turn-on oscillation frequency depends on the power loop parasitic inductance and parasitic capacitances of the freewheeling diode and load inductor. On the other hand, the turn-off oscillation frequency is found to be determined by the output parasitic capacitance of the SiC MOSFET and power loop parasitic inductance. Moreover, the shifting regularity of the turn-off maximum peak voltage with a varying switching speed is investigated on the basis of time domain simulation. The distortion of the turn-on current is theoretically analyzed. Finally, experimental results verifying the above calculations and analyses are presented.

Analysis of Switching Clamped Oscillations of SiC MOSFETs

Junji Ke,Zhibin Zhao,Zongkui Xie,Changjun Wei,Xiang Cui 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.3

SiC MOSFETs have been used to improve system efficiency in high frequency converters due to their extremely high switching speed. However, this can result in undesirable parasitic oscillations in practical systems. In this paper, models of the key components are introduced first. Then, theoretical formulas are derived to calculate the switching oscillation frequencies after full turn-on and turn-off in clamped inductive circuits. Analysis indicates that the turn-on oscillation frequency depends on the power loop parasitic inductance and parasitic capacitances of the freewheeling diode and load inductor. On the other hand, the turn-off oscillation frequency is found to be determined by the output parasitic capacitance of the SiC MOSFET and power loop parasitic inductance. Moreover, the shifting regularity of the turn-off maximum peak voltage with a varying switching speed is investigated on the basis of time domain simulation. The distortion of the turn-on current is theoretically analyzed. Finally, experimental results verifying the above calculations and analyses are presented.

Influence of Device Parameters Spread on Current Distribution of Paralleled Silicon Carbide MOSFETs

Junji Ke,Zhibin Zhao,Peng Sun,Huazhen Huang,James Abuogo,Xiang Cui 전력전자학회 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.4

This paper systematically investigates the influence of device parameters spread on the current distribution of paralleledsilicon carbide (SiC) MOSFETs. First, a variation coefficient is introduced and used as the evaluating norm for the parametersspread. Then a sample of 30 SiC MOSFET devices from the same batch of a well-known company is selected and tested underthe same conditions as those on datasheet. It is found that there is big difference among parameters spread. Furthermore,comprehensive theoretical and simulation analyses are carried out to study the sensitivity of the current imbalance to variationsof the device parameters. Based on the concept of the control variable method, the influence of each device parameter on thesteady-state and transient current distributions of paralleled SiC MOSFETs are verified separately by experiments. Finally, somescreening suggestions of devices or chips before parallel-connection are provided in terms of different applications and differentdriver configurations.

Shear Behavior of Single Cast-in Anchors in Plastic Hinge Zones

Derek Petersen,Zhibin Lin,Jian Zhao 한국콘크리트학회 2018 International Journal of Concrete Structures and M Vol.12 No.3

This paper presents two shear tests of 3/4-in. diameter cast-in anchors embedded in the plastic hinge zone of reinforced concrete columns. Design codes, such as ACI 318-14, require special reinforcement for concrete anchors in concrete that could be substantially damaged during an earthquake. The test anchors in this study were equipped with the anchor reinforcement recommended and verified in the literature. The column specimens were subjected to quasi-static cyclic loading before the test anchors were loaded in shear. Steel fracture was achieved in both test anchors despite cracks and concrete spalling occurred to the concrete within the plastic hinge zones. Meanwhile, the measured anchor capacities were smaller than the code-specified capacity, especially for the anchors subjected to cyclic shear. Concrete cover spalling was found critical to the observed capacity reduction, which caused combined bending and shear action in the anchor bolts. Measures should be developed to mitigate such adverse impact. In addition, further studies are needed for post-installed anchors before practical applications.

Influence of Device Parameters Spread on Current Distribution of Paralleled Silicon Carbide MOSFETs

Ke, Junji,Zhao, Zhibin,Sun, Peng,Huang, Huazhen,Abuogo, James,Cui, Xiang The Korean Institute of Power Electronics 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.4

This paper systematically investigates the influence of device parameters spread on the current distribution of paralleled silicon carbide (SiC) MOSFETs. First, a variation coefficient is introduced and used as the evaluating norm for the parameters spread. Then a sample of 30 SiC MOSFET devices from the same batch of a well-known company is selected and tested under the same conditions as those on datasheet. It is found that there is big difference among parameters spread. Furthermore, comprehensive theoretical and simulation analyses are carried out to study the sensitivity of the current imbalance to variations of the device parameters. Based on the concept of the control variable method, the influence of each device parameter on the steady-state and transient current distributions of paralleled SiC MOSFETs are verified separately by experiments. Finally, some screening suggestions of devices or chips before parallel-connection are provided in terms of different applications and different driver configurations.

Fatigue study on additional cutout between U shaped rib and floorbeam in orthotropic bridge deck

Xiaochen Ju,Zhibin Zeng,Xinxin Zhao,Xiaoguang Liu 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.28 No.3

The field around additional cutout of the floor beam web in orthotropic bridge deck was subjected to high stress concentration, especially the weld toe between floor beam and U shaped rib and the free edge of the additional cutout. Based on different considerations, different geometrical parameters of additional cutout were proposed in European, American and Japanese specifications, and there remained remarkable differences among them. In this study, considering influence of out-ofplane deformation of floor beam web and U shaped rib, parameter analysis for additional cutout under typical load cases was performed by fine finite element method. The influence of additional cutout shape and height to the stress distribution around the additional cutout were investigated and analyzed. Meanwhile, the static and fatigue test on this structure details was carried out. The stress distribution was consistent with the finite element analysis results. The fatigue property for additional cutout height of 95mm was slightly better than that of 61.5 mm.

Resonant Frequency Estimation of Reradiation Interference at MF from Power Transmission Lines Based on Generalized Resonance Theory

Bo, Tang,Bin, Chen,Zhibin, Zhao,Zheng, Xiao,Shuang, Wang The Korean Institute of Electrical Engineers 2015 Journal of Electrical Engineering & Technology Vol.10 No.3

The resonant mechanism of reradiation interference (RRI) over 1.7MHz from power transmission lines cannot be obtained from IEEE standards, which are based on researches of field intensity. Hence, the resonance is ignored in National Standards of protecting distance between UHV power lines and radio stations in China, which would result in an excessive redundancy of protecting distance. Therefore, based on the generalized resonance theory, we proposed the idea of applying model-based parameter estimation (MBPE) to estimate the generalized resonance frequency of electrically large scattering objects. We also deduced equation expressions of the generalized resonance frequency and its quality factor Q in a lossy open electromagnetic system, i.e. an antenna-transmission line system in this paper. Taking the frequency band studied by IEEE and the frequency band over 1.7 MHz as object, we established three models of the RRI from transmission lines, namely the simplified line model, the tower line model considering cross arms and the line-surface mixed model. With the models, we calculated the scattering field of sampling points with equal intervals using method of moments, and then inferred expressions of Padé rational function. After calculating the zero-pole points of the Padé rational function, we eventually got the estimation of the RRI’s generalized resonant frequency. Our case studies indicate that the proposed estimation method is effective for predicting the generalized resonant frequency of RRI in medium frequency (MF, 0.3~3 MHz) band over 1.7 MHz, which expands the frequency band studied by IEEE.

Understanding the friction behavior of sulfur-terminated diamond-like carbon films under high vacuum by first-principles calculations

Renhui Zhang,Juan Zhao,Yingchang Yang,Wei Shi,Zhibin Lu,Junjun Wang 한국물리학회 2018 Current Applied Physics Vol.18 No.3

Generally, the repulsive force was a key factor account for superlow friction of H or F doped diamond-like carbon (DLC) films under high vacuum. As we known, H or F doped DLC usually exhibited superlow friction under high vacuum. However, the superlow friction of S doped DLC under high vacuum was not found so far. This phenomenon was desirable to be well investigated. In this work, S-terminated diamond interfaces also exhibited strong repulsive force, however, the estimated friction coefficient was variable for S-terminated diamond interfaces. The lowest and largest friction coefficient was about 0.003 and 0.4 respectively, which indicated that the superlow friction of S doped DLC could achieve in theory. In order to well probe the unusual friction behavior of S doped DLC under high vacuum, using first-principles method, the repulsive interaction between sliding surfaces was well investigated in order to understand the unusual friction behavior of S doped DLC films.