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175 results on '"Yu, D. J."'

1. Ninety percent circular polarization detected in a repeating fast radio burst

Author

Jiang, J. C., Xu, J. W., Niu, J. R., Lee, K. J., Zhu, W. W., Zhang, B., Qu, Y., Xu, H., Zhou, D. J., Cao, S. S., Wang, W. Y., Wang, B. J., Cao, S., Zhang, Y. K., Zhang, C. F., Gan, H. Q., Han, J. L., Hao, L. F., Huang, Y. X., Jiang, P., Li, D. Z., Li, H., Li, Y., Li, Z. X., Luo, R., Men, Y. P., Qian, L., Sun, J. H., Wang, L., Xu, Y. H., Xu, R. X., Yang, Y. P., Yao, R., Yue, Y. L., Yu, D. J., Yuan, J. P., and Zhu, Y.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Fast radio bursts (FRBs) are extra-galactic sources with unknown physical mechanisms. They emit millisecond-duration radio pulses with isotropic equivalent energy of $10^{36}\sim10^{41}$ ergs. This corresponds to a brightness temperature of FRB emission typically reaching the level of $10^{36}$ K, but can be as high as above $10^{40}$ K for sub-microsecond timescale structures, suggesting the presence of underlying coherent relativistic radiation mechanisms. polarization carries the key information to understand the physical origin of FRBs, with linear polarization usually tracing the geometric configuration of magnetic fields and circular polarization probing both intrinsic radiation mechanisms and propagation effects. Here we show that the repeating sources FRB 20201124A emits $90.9\pm 1.1\%$ circularly polarized radio pulses. Such a high degree of circular polarization was unexpected in theory and unprecedented in observation in the case of FRBs, since such a high degree of circular polarization was only common among Solar or Jovian radio activities, attributed to the sub-relativistic electrons. We note that there is no obvious correlation between the degree of circular polarization and burst fluence. Besides the high degree of circular polarization, we also detected rapid swing and orthogonal jump in the position angle of linear polarization. The detection of the high degree circular polarization in FRB 20201124A, together with its linear polarization properties that show orthogonal modes, place strong constraints on FRB physical mechanisms, calling for an interplay between magnetospheric radiation and propagation effects in shaping the observed FRB radiation., Comment: 19 pages, 9 figures, 1 table, accepted for publication in National Science Review

Published
2024

3. Dissipative Instability of Magnetohydrodynamic Sausage Waves in a Compressional Cylindrical Plasma: Effect of Flow Shear and Viscosity Shear

Author

Yu, D. J.

Subjects
Astrophysics - Solar and Stellar Astrophysics, Physics - Plasma Physics, Physics - Space Physics
Abstract

The shear flow influences the stability of magnetohydrodynamic (MHD) waves. In the presence of a dissipation mechanism, flow shear may induce a MHD wave instability below the threshold of the Kelvin-Helmholtz instability (KHI), which is called dissipative instability (DI). This phenomenon is also called negative energy wave instability (NEWI) because it is closely related to the backward wave which has negative wave energy. Considering viscosity as a dissipation mechanism, we derive an analytical dispersion relation for the slow sausage modes in a straight cylinder with a discontinuous boundary. It is assumed that the steady flow is inside and dynamic and bulk viscosities are outside the circular flux tube under photospheric condition. When the two viscosities are weak, it is found that for the slow surface mode, the growth rate is proportional to the axial wavenumber and flow shear, consistent with in the incompressible limit. For a slow body mode, the growth rate has a peak at certain axial wavenumber and its order of magnitude is similar to surface mode. The linear relationship between the growth rate and the dynamic viscosity established in the incompressible limit develops nonlinearly when the flow shear and/or the two viscosities are sufficiently strong., Comment: 11 pages, 10 figures

Published
2023
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5. Effects of background periodic flow on MHD fast wave propagation to a coronal loop

Author

Yu, D. J.

Subjects
Astrophysics - Solar and Stellar Astrophysics, Physics - Fluid Dynamics, Physics - Plasma Physics
Abstract

We investigate the propagation of MHD fast waves into a cylindrical coronal loop through an inhomogeneous stationary flow region. The background flow is assumed to have a small, spatially periodic structure in addition to a constant speed. We focus on the absorption of the wave energy in Alfv\'{e}n resonance, comparing with the constant flow case. A new flow (absorption) regime is induced by the periodic flow structure which enhances the absorption for the antiparallel flow and inverse absorption (overreflection) for the parallel flow with respect to the axial wave vector, depending on the transitional layer and flow profiles. A giant overreflection and anomalous absorption behavior arise for some flow configurations. In the other flow regimes, its effect on the absorption is shown to be weak., Comment: 10 pages, 7 figures

Published
2022
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6. A fast radio burst source at a complex magnetised site in a barred galaxy

Author

Xu, H., Niu, J. R., Chen, P., Lee, K. J., Zhu, W. W., Dong, S., Zhang, B., Jiang, J. C., Wang, B. J., Xu, J. W., Zhang, C. F., Fu, H., Filippenko, A. V., Peng, E. W., Zhou, D. J., Zhang, Y. K., Wang, P., Feng, Y., Li, Y., Brink, T. G., Li, D. Z., Lu, W., Yang, Y. P., Caballero, R. N., Cai, C., Chen, M. Z., Dai, Z. G., Djorgovski, S. G., Esamdin, A., Gan, H. Q., Guhathakurta, P., Han, J. L., Hao, L. F., Huang, Y. X., Jiang, P., Li, C. K., Li, D., Li, H., Li, X. Q., Li, Z. X., Liu, Z. Y., Luo, R., Men, Y. P., Niu, C. H., Peng, W. X., Qian, L., Song, L. M., Stern, D., Stockton, A., Sun, J. H., Wang, F. Y., Wang, M., Wang, N., Wang, W. Y., Wu, X. F., Xiao, S., Xiong, S. L., Xu, Y. H., Xu, R. X., Yang, J., Yang, X., Yao, R., Yi, Q. B., Yue, Y. L., Yu, D. J., Yu, W. F., Yuan, J. P., Zhang, B. B., Zhang, S. B., Zhang, S. N., Zhao, Y., Zheng, W. K., Zhu, Y., and Zou, J. H.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Fast radio bursts (FRBs) are highly dispersed millisecond-duration radio bursts. Recent observations of a Galactic FRB suggest that at least some FRBs originate from magnetars, but the origin of cosmological FRBs is still not settled. Here we report the detection of 1863 bursts in 82 hr over 54 days from the repeating source FRB~20201124A. These observations show irregular short-time variation of the Faraday rotation measure (RM), which probes the density-weighted line-of-sight magnetic field strength, of individual bursts during the first 36 days, followed by a constant RM. We detected circular polarisation in more than half of the burst sample, including one burst reaching a high fractional circular polarisation of 75%. Oscillations in fractional linear and circular polarisations as well as polarisation angle as a function of wavelength were detected. All of these features provide evidence for a complicated, dynamically evolving, magnetised immediate environment within about an astronomical unit (au; Earth-Sun distance) of the source. Our optical observations of its Milky-Way-sized, metal-rich host galaxy reveal a barred spiral, with the FRB source residing in a low stellar density, interarm region at an intermediate galactocentric distance. This environment is inconsistent with a young magnetar engine formed during an extreme explosion of a massive star that resulted in a long gamma-ray burst or superluminous supernova., Comment: 28 pages, 10 figures, updated to match the published version

Published
2021
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7. The FAST Galactic Plane Pulsar Snapshot survey: I. Project design and pulsar discoveries

Author

Han, J. L., Wang, Chen, Wang, P. F., Wang, Tao, Zhou, D. J., Sun, Jing-Hai, Yan, Yi, Su, Wei-Qi, Jing, Wei-Cong, Chen, Xue, Gao, X. Y., Hou, Li-Gang, Xu, Jun, Lee, K. J., Wang, Na, Jiang, Peng, Xu, Ren-Xin, Yan, Jun, Gan, Heng-Qian, Guan, Xin, Huang, Wen-Jun, Jiang, Jin-Chen, Li, Hui, Men, Yun-Peng, Sun, Chun, Wang, Bo-Jun, Wang, H. G., Wang, Shuang-Qiang, Xie, Jin-Tao, Xu, Heng, Yao, Rui, You, Xiao-Peng, Yu, D. J., Yuan, Jian-Ping, Yuen, Rai, Zhang, Chun-Feng, and Zhu, Yan

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Condensed Matter - Other Condensed Matter
Abstract

Discovery of pulsars is one of the main goals for large radio telescopes. The Five-hundred-meter Aperture Spherical radio Telescope (FAST), that incorporates an L-band 19-beam receiver with a system temperature of about 20~K, is the most sensitive radio telescope utilized for discovering pulsars. We designed the {\it snapshot} observation mode for a FAST key science project, the Galactic Plane Pulsar Snapshot (GPPS) survey, in which every four nearby pointings can observe {\it a cover} of a sky patch of 0.1575 square degrees through beam-switching of the L-band 19-beam receiver. The integration time for each pointing is 300 seconds so that the GPPS observations for a cover can be made in 21 minutes. The goal of the GPPS survey is to discover pulsars within the Galactic latitude of $\pm10^{\circ}$ from the Galactic plane, and the highest priority is given to the inner Galaxy within $\pm5^{\circ}$. Up to now, the GPPS survey has discovered 201 pulsars, including currently the faintest pulsars which cannot be detected by other telescopes, pulsars with extremely high dispersion measures (DMs) which challenge the currently widely used models for the Galactic electron density distribution, pulsars coincident with supernova remnants, 40 millisecond pulsars, 16 binary pulsars, some nulling and mode-changing pulsars and rotating radio transients (RRATs). The follow-up observations for confirmation of new pulsars have polarization-signals recorded for polarization profiles of the pulsars. Re-detection of previously known pulsars in the survey data also leads to significant improvements in parameters for 64 pulsars. The GPPS survey discoveries are published and will be updated at http://zmtt.bao.ac.cn/GPPS/ ., Comment: 38 pages, 22 figures. See http://www.raa-journal.org/docs/Supp/2021Newsonline.pdf for News and Views

Published
2021
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8. Diverse polarization angle swings from a repeating fast radio burst source

Author

Luo, R., Wang, B. J., Men, Y. P., Zhang, C. F., Jiang, J. C., Xu, H., Wang, W. Y., Lee, K. J., Han, J. L., Zhang, B., Caballero, R. N., Chen, M. Z., Chen, X. L., Gan, H. Q., Guo, Y. J., Hao, L. F., Huang, Y. X., Jiang, P., Li, H., Li, J., Li, Z. X., Luo, J. T., Pan, J., Pei, X., Qian, L., Sun, J. H., Wang, M., Wang, N., Wen, Z. G., Xu, R. X., Xu, Y. H., Yan, J., Yan, W. M., Yu, D. J., Yuan, J. P., Zhang, S. B., and Zhu, Y.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown origin. Two possible mechanisms that could generate extremely coherent emission from FRBs invoke neutron star magnetospheres or relativistic shocks far from the central energy source. Detailed polarization observations may help us to understand the emission mechanism. However, the available FRB polarization data have been perplexing, because they show a host of polarimetric properties, including either a constant polarization angle during each burst for some repeaters or variable polarization angles in some other apparently one-off events. Here we report observations of 15 bursts from FRB 180301 and find various polarization angle swings in seven of them. The diversity of the polarization angle features of these bursts is consistent with a magnetospheric origin of the radio emission, and disfavours the radiation models invoking relativistic shocks., Comment: Published online in Nature on 29 Oct, 2020

Published
2020
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9. Excitation of negative energy surface magnetohydrodynamic waves in an incompressible cylindrical plasma

Author

Yu, D. J. and Nakariakov, V. M.

Subjects
Astrophysics - Solar and Stellar Astrophysics, Physics - Plasma Physics
Abstract

Negative energy wave phenomena may appear in shear flows in the presence of a wave decay mechanism and external energy supply. We study the appearance of negative energy surface waves in a plasma cylinder in the incompressible limit. The cylinder is surrounded by an axial magnetic field and by a plasma of different density. Considering flow inside and viscosity outside the flux tube, we derive dispersion relations, and obtain analytical solutions for the phase speed and growth rate (increment) of the waves. It is found that the critical speed shear for the occurrence of the dissipative instability associated with negative energy waves (NEWs) and the threshold of Kelvin--Helmholtz instability (KHI) depend on the axial wavelength. The critical shear for the appearance of sausage NEW is lowest for the longest axial wavelengths, while for kink waves the minimum value of the critical shear is reached for the axial wavelength comparable to the diameter of the cylinder. The range between the critical speed of the dissipative instability and the KHI threshold is shown to depend on the difference of the Alfv\'{e}n speeds inside and outside of the cylinder. For all axial wavenumbers, NEW appears for the shear flow speeds lower than the KHI threshold. It is easier to excite NEW in an underdense cylinder than in an overdense one. The negative energy surface waves can be effectively generated for azimuthal number $m=0$ with a large axial wave number and for higher modes ($m>0$) with a small axial wave number., Comment: 11 pages, 8 figures, accepted in ApJ

Published
2020
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10. A fast radio burst source at a complex magnetized site in a barred galaxy

Author

Xu, H., Niu, J. R., Chen, P., Lee, K. J., Zhu, W. W., Dong, S., Zhang, B., Jiang, J. C., Wang, B. J., Xu, J. W., Zhang, C. F., Fu, H., Filippenko, A. V., Peng, E. W., Zhou, D. J., Zhang, Y. K., Wang, P., Feng, Y., Li, Y., Brink, T. G., Li, D. Z., Lu, W., Yang, Y. P., Caballero, R. N., Cai, C., Chen, M. Z., Dai, Z. G., Djorgovski, S. G., Esamdin, A., Gan, H. Q., Guhathakurta, P., Han, J. L., Hao, L. F., Huang, Y. X., Jiang, P., Li, C. K., Li, D., Li, H., Li, X. Q., Li, Z. X., Liu, Z. Y., Luo, R., Men, Y. P., Niu, C. H., Peng, W. X., Qian, L., Song, L. M., Stern, D., Stockton, A., Sun, J. H., Wang, F. Y., Wang, M., Wang, N., Wang, W. Y., Wu, X. F., Xiao, S., Xiong, S. L., Xu, Y. H., Xu, R. X., Yang, J., Yang, X., Yao, R., Yi, Q. B., Yue, Y. L., Yu, D. J., Yu, W. F., Yuan, J. P., Zhang, B. B., Zhang, S. B., Zhang, S. N., Zhao, Y., Zheng, W. K., Zhu, Y., and Zou, J. H.

Published
2022
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11. Fully Gapped s-wave-like Superconducting State and Electronic Structures in the Ir0.95Pd0.05Te2 Single Crystals with Strong Spin-orbital Coupling

Author

Yu, D. J., Yang, F., Miao, Lin, Han, C. Q., Yao, Meng-Yu, Zhu, Fengfeng, Song, Y. R., Zhang, K. F., Ge, J. F., Yao, X., Zou, Z. Q., Li, Z. J., Gao, B., Guan, D. D., Liu, Canhua, Gao, C. L., Qian, Dong, and Jia, Jin-feng

Subjects
Condensed Matter - Superconductivity
Abstract

Due to the large spin-orbital coupling in the layered 5d-transition metal chalcogenides compound, the occurrence of superconductivity in Ir2-xPdxTe2 offers a good chance to search for possible topological superconducting states in this system. We did comprehensive studies on the superconducting properties and electronic structures of single crystalline Ir0.95Pd0.05Te2 samples. The superconducting gap size, critical fields and coherence length along different directions were experimentally determined. Macroscopic bulk measurements and microscopic low temperature scanning tunneling spectroscopy results suggest that Ir0.95Pd0.05Te2 possesses a BCS-like s-wave state. No sign of zero bias conductance peak were found in the vortex core at 0.4K.

Published
2014
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12. Author Correction: A fast radio burst source at a complex magnetized site in a barred galaxy

Author

Xu, H., Niu, J. R., Chen, P., Lee, K. J., Zhu, W. W., Dong, S., Zhang, B., Jiang, J. C., Wang, B. J., Xu, J. W., Zhang, C. F., Fu, H., Filippenko, A. V., Peng, E. W., Zhou, D. J., Zhang, Y. K., Wang, P., Feng, Y., Li, Y., Brink, T. G., Li, D. Z., Lu, W., Yang, Y. P., Caballero, R. N., Cai, C., Chen, M. Z., Dai, Z. G., Djorgovski, S. G., Esamdin, A., Gan, H. Q., Guhathakurta, P., Han, J. L., Hao, L. F., Huang, Y. X., Jiang, P., Li, C. K., Li, D., Li, H., Li, X. Q., Li, Z. X., Liu, Z. Y., Luo, R., Men, Y. P., Niu, C. H., Peng, W. X., Qian, L., Song, L. M., Stern, D., Stockton, A., Sun, J. H., Wang, F. Y., Wang, M., Wang, N., Wang, W. Y., Wu, X. F., Xiao, S., Xiong, S. L., Xu, Y. H., Xu, R. X., Yang, J., Yang, X., Yao, R., Yi, Q. B., Yue, Y. L., Yu, D. J., Yu, W. F., Yuan, J. P., Zhang, B. B., Zhang, S. B., Zhang, S. N., Zhao, Y., Zheng, W. K., Zhu, Y., and Zou, J. H.

Published
2022
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13. YBCO-buffered NdBCO film with higher thermal stability in seeding REBCO Growth

Author

Xu, H. H., Chen, Y. Y., Cheng, L., Yan, S. B., Yu, D. J., and Yao, X.

Subjects
Condensed Matter - Superconductivity, 82d55
Abstract

In this work, we report a strengthened superheating effect caused by a buffering YBa2Cu3Oy (Y123 or YBCO) layer in the Nd1+xBa2-xCu3O7-y (Nd123 or NdBCO) thin film with MgO substrate (i.e., NdBCO/YBCO/MgO thin film). In the cold-seeding melt-textured (MT) growth, the NdBCO/YBCO/MgO film presented an even higher superheating level, about 20 {\deg}C higher than that of non-buffered NdBCO film (i.e., NdBCO/MgO film). Using this NdBCO/YBCO/MgO film as seeds and undergoing a maximum processing temperature (Tmax) up to 1120 {\deg}C, we succeeded in growing various RE1+xBa2-xCu3O7-y (REBCO, RE=rare elements) bulk superconductors, including Gd1+xBa2-xCu3O7-y (GdBCO), Sm1+xBa2-xCu3O7-y (SmBCO) and NdBCO that have high peritectic temperatures (Tp). The pole figure (X-Ray \phi-scan) measurement reveals that the NdBCO/YBCO/MgO film has better in-plane alignment than the NdBCO/MgO film, indicating that the induced intermediate layer improves the crystallinity of the NdBCO film, which could be the main origin of the enhanced thermal stability. In short, possessing higher thermal stability and enduring a higher Tmax in the MT process, the NdBCO/YBCO/MgO film is beneficial to the growth of bulk superconductors in two aspects: (1) broad application for high-Tp REBCO materials; (2) effective suppression against heterogeneous nucleation, which is of great assistance in growing large and high-performance REBCO crystals., Comment: 9 pages, 4 figures

Published
2011
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15. Learning a Self-organizing Map Model on a Riemannian Manifold

Author

Yu, D. J., Hancock, E. R., Smith, W. A. P., Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Nierstrasz, Oscar, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Sudan, Madhu, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Vardi, Moshe Y., Series editor, Weikum, Gerhard, Series editor, Hancock, Edwin R., editor, Martin, Ralph R., editor, and Sabin, Malcolm A., editor

Published
2009
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16. On capturing human agency and methodological interdisciplinarity in socio-hydrology research

Author

Yu, D. J. Haeffner, M. Jeong, H. Pande, S. Dame, J. Di Baldassarre, G. Garcia-Santos, G. Hermans, L. Muneepeerakul, R. Nardi, F. Sanderson, M. R. Tian, F. Wei, Y. Wessels, J. Sivapalan, M. and Yu, D. J. Haeffner, M. Jeong, H. Pande, S. Dame, J. Di Baldassarre, G. Garcia-Santos, G. Hermans, L. Muneepeerakul, R. Nardi, F. Sanderson, M. R. Tian, F. Wei, Y. Wessels, J. Sivapalan, M.

Abstract

Socio-hydrology has expanded and been effective in exposing the hydrological community to ideas and approaches from other scientific disciplines, and social sciences in particular. Yet it still has much to explore regarding how to capture human agency and how to combine different methods and disciplinary views from both the hydrological and the social sciences to develop knowledge. A useful starting ground is noting that the complexity of human–water relations is due to interactions not only across spatial and temporal scales but also across different organizational levels of social systems. This calls for consideration of another analytical scale, the human organizational scale, and interdisciplinarity in study methods. Based on the papers published in this journal’s Special Issue Advancing Socio-hydrology over 2019–2022, this paper illuminates how the understanding of coupled human–water systems can be strengthened by capturing the multi-level nature of human decision making and by applying an interdisciplinary multi-method approach.

Published
2022
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18. The FAST Galactic Plane Pulsar Snapshot survey: I. Project design and pulsar discoveries ⋆

Author

Han, J. L., primary, Wang, Chen, additional, Wang, P. F., additional, Wang, Tao, additional, Zhou, D. J., additional, Sun, Jing-Hai, additional, Yan, Yi, additional, Su, Wei-Qi, additional, Jing, Wei-Cong, additional, Chen, Xue, additional, Gao, X. Y., additional, Hou, Li-Gang, additional, Xu, Jun, additional, Lee, K. J., additional, Wang, Na, additional, Jiang, Peng, additional, Xu, Ren-Xin, additional, Yan, Jun, additional, Gan, Heng-Qian, additional, Guan, Xin, additional, Huang, Wen-Jun, additional, Jiang, Jin-Chen, additional, Li, Hui, additional, Men, Yun-Peng, additional, Sun, Chun, additional, Wang, Bo-Jun, additional, Wang, H. G., additional, Wang, Shuang-Qiang, additional, Xie, Jin-Tao, additional, Xu, Heng, additional, Yao, Rui, additional, You, Xiao-Peng, additional, Yu, D. J., additional, Yuan, Jian-Ping, additional, Yuen, Rai, additional, Zhang, Chun-Feng, additional, and Zhu, Yan, additional

Published
2021
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24. Diverse polarization angle swings from a repeating fast radio burst source

Author

Luo, R., primary, Wang, B. J., additional, Men, Y. P., additional, Zhang, C. F., additional, Jiang, J. C., additional, Xu, H., additional, Wang, W. Y., additional, Lee, K. J., additional, Han, J. L., additional, Zhang, B., additional, Caballero, R. N., additional, Chen, M. Z., additional, Chen, X. L., additional, Gan, H. Q., additional, Guo, Y. J., additional, Hao, L. F., additional, Huang, Y. X., additional, Jiang, P., additional, Li, H., additional, Li, J., additional, Li, Z. X., additional, Luo, J. T., additional, Pan, J., additional, Pei, X., additional, Qian, L., additional, Sun, J. H., additional, Wang, M., additional, Wang, N., additional, Wen, Z. G., additional, Xu, R. X., additional, Xu, Y. H., additional, Yan, J., additional, Yan, W. M., additional, Yu, D. J., additional, Yuan, J. P., additional, Zhang, S. B., additional, and Zhu, Y., additional

Published
2020
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26. Universal scaling behavior of resonant absorption

Author

Yu, D. J. and Van Doorsselaere, T.

Subjects
REFLECTION, FOS: Physical sciences, Type (model theory), 01 natural sciences, 010305 fluids & plasmas, Physics, Fluids & Plasmas, 0103 physical sciences, Ideal (ring theory), 010306 general physics, Absorption (electromagnetic radiation), Scaling, Solar and Stellar Astrophysics (astro-ph.SR), Physics, Science & Technology, ANALYTIC EXPRESSIONS, PLASMA, Mode (statistics), LOCALIZATION, Coronal loop, Condensed Matter Physics, Wave equation, LANGMUIR, Physics - Plasma Physics, Plasma Physics (physics.plasm-ph), Astrophysics - Solar and Stellar Astrophysics, Quantum electrodynamics, Physical Sciences, LINEAR-MODE CONVERSION, ALFVEN WAVES, Magnetohydrodynamics, INVARIANT-IMBEDDING APPROACH, ELECTROMAGNETIC-WAVES
Abstract

Mode conversion and resonant absorption are crucial mechanisms for wave transport and absorption. Scaling behavior of mode conversion or resonant absorption is well-known for electromagnetic and MHD waves in planar geometry. Our recent study showed that such a scaling behavior of resonant absorption could also exist for coronal loop oscillations with cylindrical geometry, but it was only tested for one density profile. Here we generalise our previous study on the scaling behavior of resonant absorption by considering multiple density profiles. Applying an invariant imbedding method to the ideal MHD wave equations, we show that the scaling behavior also exists for these density models. We thus generalise our earlier results and show that such a universal scaling exists in cylindrical geometry, too. Given these results and the earlier results in planar geometry, we formulate a hypothesis that a universal scaling behavior exists regardless of the type of mode conversion or resonant absorption., 6 pages, 4 figures

Published
2019

29. Two-layer batch-process of YBa2Cu3Ox bulk superconductors induced by NdBa2Cu3Ox film-seeds.

Author

Yu, D. J., Cheng, L., Peng, B. N., Chen, Y. Y., Xu, H. H., Li, H., Yao, X., and Ikuta, H.

Subjects
*MAGNESIUM oxide, *THIN film research, *DISSOLUTION (Chemistry), *DIFFUSION, *THERMAL stability
Abstract

Applying a cost-effective process with a simple one-side-heating furnace, two layers of YBa2Cu3Ox (YBCO) bulks were successfully grown in one batch by using NdBa2Cu3Ox (NdBCO) thin-film-seeds deposited on MgO substrates. Due to the large temperature difference between the two layers, the seed-induced growth began at the bottom layer much later than that at the top layer. Remarkably, NdBCO films on the bottom layer samples survived a long time (over 15 h) above the growth temperature and effectively induced the YBCO growth. The significant thermal stability of the films, i.e., the tolerance for a long holding time on the surface of the molten pellet, is supposed to relate to a competition between the dissolution/diffusion of film materials into the liquid and NdBCO grain coarsening/Nd-YBCO crystallization. [ABSTRACT FROM AUTHOR]

Published
2013
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30. Correlations of UGT1A1 gene polymorphisms with onset and prognosis of non-small cell lung cancer.

Author

HAN, Z.-F., LIN, S.-T., ZHONG, M., and YU, D.-J.

Abstract

OBJECTIVE: The aim of this study was to investigate the correlations of UDP glucuronosyltransferase family 1 member A1 (UGT1A1) gene polymorphisms with the onset and prognosis of non-small cell lung cancer. PATIENTS AND METHODS: A total of 400 patients with non-small cell lung cancer (disease group) and healthy controls (control group) in our hospital were selected as research subjects. Genomic DNA was extracted from the peripheral blood. UGT1A1 gene polymorphisms rs8330, rs4148323 and rs35003977 were detected after Polymerase Chain Reaction (PCR) amplification. RT-qPCR was performed to measure the expression level of UGT1A1. The survival of patients was analyzed combined with their prognosis. Moreover, the expression of UGT1A1 gene in lung cancer patients from The Cancer Genome Atlas (TCGA) database was analyzed by bioinformatics, and the prognosis was analyzed. RESULTS: According to the expression level of UGT1A1 gene from TCGA and GTEx databases, UGT1A1 gene was highly expressed in lung cancer tissues but lowly expressed in normal lung tissues, and the difference was statistically significant (p<0.05). Combined with the expression level of UGT1A1 and the prognostic information of lung cancer patients from TCGA database, patients with higher expression level of UGT1A1 gene exhibited significantly better prognosis than those with lower level (p=0.0013), suggesting that UGT1A1 gene is an anti-oncogene. There were statistically differences in allele distribution of UGT1A1 gene polymorphism rs8330 between the disease group and control group (p=0.003), and the frequency of allele G was higher in disease group. Moreover, the distribution of genotypes of UGT1A1 gene polymorphisms rs8330 (p=0.006) and rs4148323 (p=0.003) in the disease group was significantly different from that in the control group, and the frequencies of GG genotype of polymorphisms rs8330 and rs4148323 were higher in the disease group. Statistically significant differences in the distribution of recessive models of UGT1A1 gene polymorphism rs8330 were observed between the disease group and control group (p=0.047), and the disease group exhibited a lower frequency of recessive model GC + CC than control group. There were evident differences in the distribution of haplotype GGT of UGT1A1 gene polymorphisms rs8330, rs4148323 and rs35003977 between the disease group and control group (p=0.004), and the frequencies of haplotype GGT were higher in the disease group than those in the control group. UGT1A1 gene polymorphism rs8330 was remarkably associated with gene expression (p<0.05). Meanwhile, the expression of UGT1A1 gene in patients carrying genotype CC declined notably compared with that in patients carrying genotypes GG and GC (p<0.05). Furthermore, the polymorphism rs8330 had a significant correlation with the survival of patients in disease group (p=0.0001), and patients with genotype CC had the worst prognosis. CONCLUSIONS: UGT1A1 gene polymorphisms are prominently correlated with the onset and prognosis of non-small cell lung cancer. [ABSTRACT FROM AUTHOR]

Published
2020

31. Linc00703 suppresses non-small cell lung cancer progression by modulating CyclinD1/CDK4 expression.

Author

SUN, H.-B., HAN, X.-L., ZHONG, M., and YU, D.-J.

Abstract

OBJECTIVE: The aim of this study was to detect the expression of linc00703 in non-small cell lung cancer (NSCLC), and to explore the biological function and potential molecular mechanism of linc00703 in NSCLC using in vitro experiments. PATIENTS AND METHODS: The carcinoma tissues and para-carcinoma tissues were collected from 32 patients diagnosed with NSCLC, from which the RNA was extracted. The relative expression of linc00703 in NSCLC tissues was detected via quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The NSCLC cells and normal human bronchial epithelial cells were selected, in which the relative expression of linc00703 was determined via qRT-PCR. Next, the linc00703 overexpression plasmids were designed and synthesized, and then transiently transfected into NSCLC cells. After 48 h, the overexpression efficiency was detected. Finally, the changes in cell proliferation, apoptosis, cycle distribution and expressions of downstream molecular markers were determined using cell counting kit-8 (CCK8) assay, colony formation assay, flow cytometry and Western blotting, respectively, after overexpression of linc00703 in NSCLC cells. RESULTS: The results of qRT-PCR revealed that the expression of linc00703 was down-regulated by 5.14 times on average in 29 out of 32 cases of NSCLC tissues, and it was also down-regulated in NSCLC cells. Besides, it was found through CCK-8 assay, colony formation assay and flow cytometry that after overexpression of linc00703 in NSCLC cells, the cell proliferation was inhibited, the apoptosis was enhanced, and the cell cycle was arrested in G1/ G0 phase. Furthermore, the results of Western blotting showed that after overexpression of linc00703, the protein expressions of cyclinD1 and cyclin-dependent kinase 4 (CDK4) declined, while those of cyclinE1 and CDK2 did not change. CONCLUSIONS: The expression of linc00703 is down-regulated in NSCLC, and it suppresses the occurrence and development of NSCLC via mediating the expression of cyclinD1/CDK4. [ABSTRACT FROM AUTHOR]

Published
2020

32. MicroRNA-597 inhibits NSCLC progression through negatively regulating CDK2 expression.

Author

YU, D.-J., LI, Y.-H., and ZHONG, M.

Abstract

OBJECTIVE: Previous studies have shown that microRNA-597 serves as a tumor suppressor gene. However, the role of microRNA-597 in non-small cell lung cancer (NSCLC) has not been fully elucidated. Therefore, the aim of this study was to investigate the expression of microRNA- 597 in NSCLC, and to further explore the possible underlying mechanism. PATIENTS AND METHODS: Real-time quantitative polymerase chain reaction (qPCR) was performed to examine microRNA-597 level in tumor tissues and para-cancerous normal tissues collected from 50 patients with NSCLC. The interplay between microRNA-597 expression and clinical indicators, as well as prognosis of NSCLC patients, was analyzed. Meanwhile, qPCR was used to verify microRNA-59 level in NSCLC cell lines. Subsequently, microRNA- 597 overexpression and knockdown models were constructed using lentivirus in NSCLC cell lines (including H1299 and PC-9). The impacts of microRNA-597 on the biological functions of NSCLC cells were evaluated using cell counting kit-8 (CCK-8), colony formation, and 5-Ethynyl-2'-deoxyuridine (EdU) assay, respectively. Finally, luciferase reporter gene assay and recovery experiment were performed to investigate the underlying molecular mechanism. RESULTS: QPCR results indicated that microRNA- 597 level in NSCLC tissues was remarkably lower than that of adjacent normal tissues, and the difference was statistically significant (p<0.05). Compared with patients with high expression of microRNA-597, patients with low expression of microRNA-597 exhibited significantly higher incidence of pathological stage and lower overall survival rate (p<0.05). Similarly, compared with NC group, the proliferation ability of NSCLC cells was remarkably weakened in microRNA-597 overexpression group (p<0.05). However, the opposite results were observed in microRNA-597 inhibitor group (p<0.05). CDK2 expression was found remarkably elevated in NSCLC cell lines as well as in tissue samples CDK2 expression. Meanwhile, CDK2 expression was negatively correlated with microRNA- 597 expression. Luciferase reporter gene assay demonstrated that overexpression of CDK2 could significantly attenuate the luciferase activity of wild-type microRNA-597 vector without attenuating that of mutant vector CDK2 expression. This further suggested that microRNA-597 could target bind to CDK2. Furthermore, cell recovery experiment revealed that CDK2 could reverse the impact of microRNA-597 on the malignant progression of NSCLC. CONCLUSIONS: MicroRNA-597 expression was significantly down-regulated in NSCLC tissues, as well as cell lines. Meanwhile, microRNA- 597 expression was associated with the pathological staging and poor prognosis of patients with NSCLC. In addition, microRNA-597 might suppress the malignant progression of NSCLC through the regulation of CDK2. [ABSTRACT FROM AUTHOR]

Published
2020

34. Recycling failed bulk YBCO superconductors using the NdBCO/YBCO/MgO film-seeded top-seeded melt growth method.

Author

Xu, H. H., Cheng, L., Yan, S. B., Yu, D. J., Guo, L. S., and Yao, X.

Subjects
MICROSTRUCTURE, SUPERCONDUCTORS, OXYGENATION (Chemistry), RARE earth metals, ENGINEERING
Abstract

REBa2Cu3Oy (RE123 or REBCO, RE = rare earth elements) bulk high-temperature superconductors have a potential perspective for large-scale engineering applications. However, the cost of REBCO bulk production is rather high, considering high failure rates, expensive RE materials, and Pt or Ag addition. Using the cold-seeding in the top-seeded melt growth, a simple and feasible process, we succeeded in recycling the failed REBCO (RE = Y) bulks. The distinctive feature of this recycling process is the use of YBCO-buffered NdBCO films as seeds, which have high thermal stability and can endure a maximum processing temperature (Tmax) up to 1120 °C to enable full decomposition of solid REBCO. Three typical microstructures were recognized in the failed samples attributed to the inherent differences in the non-optimized growth heating profiles. Preferential recycling procedures were chosen according to the difficulty of the failed-samples decomposition, which has a certain connection with the microstructures of the failed bulks. Finally, after oxygenation, the recycled bulks demonstrate good superconducting properties. [ABSTRACT FROM AUTHOR]

Published
2012
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36. Long noncoding RNA CASC15 is upregulated in non-small cell lung cancer and facilitates cell proliferation and metastasis via targeting miR-130b-3p.

Author

YU, D.-J., ZHONG, M., and WANG, W.-L.

Abstract

OBJECTIVE: Recent researches have discovered a class of long noncoding RNAs (lncRNAs), which are dysregulated in various tumors and linked to carcinogenesis. This study aims to uncover the molecular functions of lncRNA CASC15 in non-small cell lung cancer (NSCLC) tumorigenesis. PATIENTS AND METHODS: Real Time-quantitative Polymerase Chain Reaction (RT-qPCR) was performed to detect CASC15 expression in 55 NSCLC samples and four NSCLC cell lines. Besides, the function of CASC15 was detected through proliferation assay, transwell assay, and wound healing assay in NSCLC cells. Furthermore, the interaction between CASC15 and miR-130b-3p in NSCLC was studied by performing dual-luciferase reporter assay. In addition, tumor formation and metastasis assay were performed in vivo. RESULTS: CASC15 expression was remarkably upregulated in NSCLC samples compared with that in adjacent samples. Cell proliferation, invasion, and migration in NSCLC were inhibited via knockdown of CASC15 in vitro. Moreover, RT-qPCR results revealed that miR-130b-3p was upregulated via knockdown of CASC15 in vitro. In addition, miR-130b-3p was a direct target of CASC15 in NSCLC. Tumor formation and metastasis were inhibited after CASC15 was knockdown in vivo. CONCLUSIONS: Our study indicates that CASC15 could promote metastasis and proliferation of NSCLC through sponging miR-130b-3p in vitro and in vivo, which may offer a new therapeutic intervention for NSCLC patients. [ABSTRACT FROM AUTHOR]

Published
2019

37. LncRNA HAGLROS accelerates the progression of lung carcinoma via sponging microRNA-152.

Author

WANG, W. L., YU, D. J., and ZHONG, M.

Abstract

OBJECTIVE: The aim of this study was to analyze the expression profiling of long non-coding RNA (lncRNA) HAGLROS and microRNA-152 in lung carcinoma (LCa), and to explore their regulatory effects on the malignant progression of LCa. PATIENTS AND METHODS: The expression of HAGLROS in 44 paired LCa tissues and matched adjacent tissues was determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The correlation between HAGLROS expression and clinical indexes of LCa patients was analyzed. Furthermore, HAGLROS expression in LCa cell lines was detected as well. The HAGLROS over-expression and knockdown models were established in A549 and SPC-A1 cells by transfection of pcDNA-HAGLROS and anti-HAGLROS, respectively. The biological influences of HAGLROS on LCa cells were evaluated through a series of functional experiments. Furthermore, the potential relationship between HAGLROS and microRNA-152 was analyzed. RESULTS: HAGLROS was highly expressed in LCa tissues compared with adjacent normal tissues. LCa patients with a higher expression of HAGLROS presented significantly worse tumor stage, a higher rate of lymphatic metastasis, and a lower survival. The knockdown of HAGLROS significantly attenuated the proliferative and migratory abilities of LCa cells. Meanwhile, HAGLROS over-expression obtained the opposite results. MicroRNA-152 was negatively correlated with HAGLROS in LCa. Rescue experiments showed that the knockdown of microRNA-152 reversed the regulatory effects of HAGLROS on proliferative and migratory abilities of LCa cells. CONCLUSIONS: HAGLROS expression is correlated with tumor stage and lymphatic metastasis of LCa patients. Furthermore, HAGLROS accelerates proliferation and migration of LCa cells by regulating microRNA-152. [ABSTRACT FROM AUTHOR]

Published
2019

38. Long non-coding RNA OR3A4 is associated with poor prognosis of human non-small cell lung cancer and regulates cell proliferation via up-regulating SOX4.

Author

ZHONG, M., WANG, W. L., and YU, D. J.

Abstract

OBJECTIVE: Recent studies have uncovered that long noncoding RNAs (lncRNAs) play a crucial role in the progression of malignant tumors. Non-small cell lung cancer (NSCLC) is a common type of fatal cancer worldwide. The aim of this study was to identify the specific function of lncRNA OR3A4 in the progression of NSCLC, and to explore the possible underlying mechanism. PATIENTS AND METHODS: LncRNA OR3A4 expression in 52-paired NSCLC tissues and adjacent normal tissues was detected by quantitative real-time polymerase chain reaction (qRTPCR). Cell proliferation assay and cell apoptosis assay were used to investigate the function of OR3A4 in NSCLC. Furthermore, the underlying mechanism was explored by qRT-PCR and Western blot assay. RESULTS: OR3A4 expression was remarkably upregulated in NSCLC tissues when compared with adjacent normal tissues. The overall survival of NSCLC patients in high OR3A4 expression group was significantly worse than those in low OR3A4 expression group. After the silence of OR3A4, the proliferation of NSCLC cells was significantly inhibited. Besides, the apoptosis of NSCLC cells was remarkably promoted after the silence of OR3A4. Meanwhile, knockdown of OR3A4 significantly down-regulated the mRNA and protein levels of SOX4 in NSCLC cells. Furthermore, the expression of SOX4 was found upregulated in both NSCLC tissues and cells. CONCLUSIONS: These above results suggested that OR3A4 could promote cell proliferation and suppress cell apoptosis in NSCLC through up-regulating SOX4. Our findings demonstrated that OR3A4 might serve as a new therapeutic intervention for NSCLC patients. [ABSTRACT FROM AUTHOR]

Published
2019

39. LncRNA FBXL19-AS1 promotes proliferation and metastasis via regulating epithelial-mesenchymal transition in non-small cell lung cancer.

Author

YU, D.-J., LI, Y.-H., and ZHONG, M.

Abstract

OBJECTIVE: To detect the relative expression of long non-coding ribonucleic acid (lncRNA) F-box and leucine-rich repeat protein 19-antisense RNA 1 (FBXL19-AS1) in tissues and cells of non-small-cell lung cancer (NSCLC), and investigate the mechanism of lncRNA FBXL19-AS1 in promoting NSCLC cell proliferation and metastasis by regulating epithelial-mesenchymal transition (EMT) via in vitro experiments. PATIENTS AND METHODS: The relative expression of lncRNA FBXL19-AS1 in NSCLC tissues and cells was detected via quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The colony formation assay was performed to study the impact of interference with lncRNA FBXL19-AS1 expression on NSCLC cell proliferation. The flow cytometry was applied to determine the influence of si-FBXL19-AS1 on the cycle distribution of NSCLC cells. After the interference with lncRNA FBXL19-AS1 expression, the transwell assay was utilized to measure the changes in the migratory and invasive abilities of NSCLC cells, while the expression changes in EMT-related molecular markers was detected via Western blotting. RESULTS: The results of qRT-PCR showed that the expression of lncRNA FBXL19-AS1 in NSCLC tissues and cells was up-regulated. According to the results of the colony formation assay, the proliferative capacity of NSCLC cells was decreased after the interference with lncRNA FBXL19-AS1 expression. In flow cytometry, it was indicated that the cell cycle was arrested at the G0/G1 phase in the experimental group compared with that in the control group. The transwell assay results showed that the migratory and invasive abilities of NSCLC cells were weakened after the interference with lncRNA FBXL19-AS1 expression. The results of the Western blotting assay revealed that the expressions of EMT-related molecular markers (E-cadherin, N-cadherin, etc.) were changed. CONCLUSIONS: The expression of lncRNA FBXL19-AS1 in NSCLC tissues and cells is up-regulated, and the highly expressed lncRNA FBXL19-AS1 can promote NSCLC cell proliferation and metastasis by regulating the EMT. [ABSTRACT FROM AUTHOR]

Published
2019

42. MiR-1269a acts as an onco-miRNA in non-small cell lung cancer via down-regulating SOX6.

Author

JIN, R.-H., YU, D.-J., and ZHONG, M.

Abstract

OBJECTIVE: Lung cancer, especially non-small cell lung cancer (NSCLC), remains one of the leading death-causing malignant tumors worldwide. MicroRNAs (miRNAs) have been identified to participate in the development and progression of NSCLC. However, the role of miR-1269a in NSCLC still needs to be elucidated. The objective of this study was to investigate the function of miR-1269a in NSCLC and its underlying mechanism. PATIENTS AND METHODS: Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) was utilized to measure the expression level of miR-1269a in NSCLC tissues and cell lines. After transfection with miR-1269a mimics or inhibitors, the expression level of miR-1269a in NSCLC was up-or down-regulated. Cell Counting Kit-8 (CCK-8) assay and colony formation assay were used to measure cell proliferation ability. Flow cytometry assay was applied to verify the cell cycle distributions of established cell lines. The potential target of miR-1269a was determined by using dual-luciferase and Western blot assays. RESULTS: miR-1269a was significantly over-expressed in NSCLC tissues than that in adjacent normal tissues. The expression of miR-1269a was also up-regulated in NSCLC-derived cell lines. Up-regulation of miR-1269a improved the abilities of cell proliferation, colony formation, and induced cell cycle transition. Meanwhile, down-regulation of miR-1269a decreased the capacities of cell proliferation, colony formation, and arrested the cell cycle. It was further implicated that SOX6 was verified as a target of miR-1269a in NSCLC and over-expressed SOX6 could rescue the effect of miR-1269a up-regulation. CONCLUSIONS: Our study demonstrated that miR-1299a could function as an onco-miRNA in NSCLC and promote NSCLC growth via down-regulating the expression of SOX6. [ABSTRACT FROM AUTHOR]

Published
2018

43. The effects of recombinant human growth hormone (rHGH) on survival of slender narrow pedicle flap and expressions of vascular endothelial growth factor (VEGF) and classification determinant 34 (CD34).

Author

SUN, W., YU, W. -Y., YU, D. -J., ZHAO, T. -L., WU, L. -J., and HAN, W. -Y.

Abstract

OBJECTIVE: To explore the effects of recombinant human growth hormone (rHGH) on the survival of the mouse slender narrow pedicle flap and the expressions of vascular endothelial growth factor (VEGF) and classification determinant 34 (CD34). MATERIALS AND METHODS: A total of 20 BALB/c mice were randomly divided into the experimental group (n=10) and control group (n=10). The flaps were transplanted for mice in two groups respectively. 6 h after the operation, the mice in the experimental group were administrated with rHGH via local subcutaneous injection, while the mice in the control group were injected with the same amount of normal saline. The laser Doppler was used to measure the subflap blood flow rates before the operation, and 3 days, 7 days and 14 days after the operation, respectively; the flap necrosis and survival areas of mice in two groups were measured respectively, and the survival rate of the flap was calculated 14 days after the operation. Afterwards, the flaps of mice in two groups were exfoliated and the shape and structure of flap tissues were tested by the hematoxylin-eosin (HE) staining. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blot were used to test the levels of mRNA and protein of VEGF and CD34 in the flap tissues. RESULTS: The flaps of mice in the control group mainly exhibited the black or grayish- black and lost the elasticity with the hard texture, while those in the experimental group were ruddy in color with favorable elasticity. The survival rate of flaps of mice in the experimental group was significantly higher than that in the control group (83.61 ± 12.56% vs. 46.25 ± 9.70%) and the necrosis area of flaps of mice in the experimental group was significantly smaller than that in the control group (1.32 ± 0.16 vs. 4.13 ± 0.35, p < 0.05). There were no statistical differences in the blood flow rates of mouse flap both before the operation and three days after the operation between two groups (p > 0.05), while the blood flow rates of mouse flap both 7 days and 3 days after the operation in the experimental group were higher than those in the control group (p > 0.05). Compared with those in the control group, the levels of VEGF and CD34 were significantly increased, but the levels of the inflammatory factors of the interleukin-6 (IL- 6) and tumor necrosis factor-α (TNF-α) were significantly decreased (p < 0.05). CONCLUSIONS: rHGH plays an active role in the survival of the flap through promoting the angiogenesis and inhibiting inflammatory reaction. [ABSTRACT FROM AUTHOR]

Published
2018

44. Adipose-derived stem cells improve neovascularization in ischemic flaps in diabetic mellitus through HIF-1α/VEGF pathway.

Author

YU, W.-Y., SUN, W., YU, D.-J., ZHAO, T.-L., WU, L.-J., and ZHUANG, H.-R.

Abstract

OBJECTIVE: To investigate the improvement effect of adipose-derived stem cells on neovascularization in an ischemic flap in diabetes mellitus (DM), and to explore the mechanism of hypoxia-inducible factor 1α (HIF-1α)/vascular endothelial growth factor (VEGF) pathway. MATERIALS AND METHODS: A total of 60 male Sprague-Dawley (SD) rats were divided into control group, model group, and adipose-derived stem cells (ADSCs) group. The survival rate of the flap and the number of new blood vessels were measured. The content of VEGF was determined by enzyme-linked immunosorbent assay (ELISA) kit. Then, the expressions of HIF-1α and VEGF in each group were measured by immunohistochemistry. Reverse transcriptase polymerase chain reaction (RT-PCR) method and Western blotting assay were used to detect the mRNA and protein expression of HIF-1α and VEGF in each group. RESULTS: Compared with control group, the flap survival rate of model group was decreased significantly, and the number of new blood vessels was also decreased significantly. Compared with model group, the flap survival rate of ADSCs group was increased significantly, and the number of new blood vessels was also increased significantly. The results of ELISA showed that compared with control group, the level of VEGF in model group was lower than that in model group, and the level of VEGF in the ADSC group was significantly higher than that in the model group. IHC results showed that both HIF-1α and VEGF proteins were decreased significantly in model group, whereas the expression of HIF-1α and VEGF in the ADSCs group was increased significantly. The results of RTPCR and the Western blotting showed the mRNA and protein expressions in model group were all decreased, while those in ADSCs group were significantly increased (p < 0.05). CONCLUSIONS: ADSCs can improve the neovascularization of diabetic ischemic skin by regulating the HIF-1α/VEGF pathway. [ABSTRACT FROM AUTHOR]

Published
2018

47. Influences of cisatracurium besylate and vecuronium bromide on muscle relaxant effects and electromyography of tracheal intubation under general anesthesia.

Author

YU, D.-J. and GAO, H.-Y.

Abstract

OBJECTIVE: To observe the influences of atracurium besylate and vecuronium bromide on muscle relaxant effects and electromyography of patients with tracheal intubation under general anesthesia in thyroid surgery. PATIENTS AND METHODS: 120 patients treated with thyroid surgery were randomly divided into group A and group V. Patients in group A were administered with cisatracurium besylate combined with propofol and fentanyl for induction of tracheal intubation under general anesthesia. Patients in group V were administered with 0.10 mg/kg vecuronium bromide combined with propofol and fentanyl for induction of tracheal intubation under general anesthesia. Then, the amplitude in electromyography was observed 30-70 min after I.V. muscle relaxant medicine to record the time for patients to reach 0% TW convulsion in abductor pollicis muscle and to observe the muscle relaxant effects. RESULTS: There was no statistical difference in the time to reach 0% TW in two groups (p>0.05). After 30 min of injection of muscle relaxants, EMG positive rate and TW value in group A were significantly higher than those in group V (p<0.05). After 50-70 min of injection of muscle relaxants, EMG positive rate of patients in two groups was up to 100%, and EMG amplitude in group A was significantly higher than a that in group V (p< 0.05). The time of taking muscle relaxant effects in group A was significantly faster than that in group V (p<0.05), while the recovery time of autonomous respiration and the time of autonomous body activity in group A were slightly lower than those in group V (p>0.05). There was no statistical difference in the time of eye-opening of both groups (p>0.05) . MAP and HR of patients in both groups showed no statistical diffence before and after injection (p>0.05). CONCLUSIONS: Average EMG amplitude and the positive rate of effective EMG amplitude of cisatracurium besylate are all higher than those of vecuronium bromide. With faster effects and shorter action time, cisatracurium besylate is more suitable in thyroid surgery IONM (intraoperative neurophysiological monitoring). [ABSTRACT FROM AUTHOR]

Published
2017

49. Fully gappeds-wave-like superconducting state and electronic structure in Ir0.95Pd0.05Te2single crystals with strong spin-orbital coupling

Author

Yu, D. J., primary, Yang, F., additional, Miao, Lin, additional, Han, C. Q., additional, Yao, Meng-Yu, additional, Zhu, Fengfeng, additional, Song, Y. R., additional, Zhang, K. F., additional, Ge, J. F., additional, Yao, X., additional, Zou, Z. Q., additional, Li, Z. J., additional, Gao, B. F., additional, Liu, Canhua, additional, Guan, D. D., additional, Gao, C. L., additional, Qian, Dong, additional, and Jia, Jin-feng, additional

Published
2014
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