473 results on '"Zhu, YB"'
Search Results
2. Phase-space dependent critical gradient behavior of fast-ion transport due to Alfvén eigenmodes
- Author
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Collins, CS, Heidbrink, WW, Podestà, M, White, RB, Kramer, GJ, Pace, DC, Petty, CC, Stagner, L, Van Zeeland, MA, and Zhu, YB
- Subjects
energetic particles ,fast-ion transport ,Alfven eigenmodes ,critical gradient ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Fluids & Plasmas - Abstract
Experiments in the DIII-D tokamak show that many overlapping small-amplitude Alfvén eigenmodes (AEs) cause fast-ion transport to sharply increase above a critical threshold in beam power, leading to fast-ion density profile resilience and reduced fusion performance. The threshold is above the AE linear stability limit and varies between diagnostics that are sensitive to different parts of fast-ion phase-space. Comparison with theoretical analysis using the nova and orbit codes shows that, for the neutral particle diagnostic, the threshold corresponds to the onset of stochastic particle orbits due to wave-particle resonances with AEs in the measured region of phase space. The bulk fast-ion distribution and instability behavior was manipulated through variations in beam deposition geometry, and no significant differences in the onset threshold outside of measurement uncertainties were found, in agreement with the theoretical stochastic threshold analysis. Simulations using the 'kick model' produce beam ion density gradients consistent with the empirically measured radial critical gradient and highlight the importance of including the energy and pitch dependence of the fast-ion distribution function in critical gradient models. The addition of electron cyclotron heating changes the types of AEs present in the experiment, comparatively increasing the measured fast-ion density and radial gradient. These studies provide the basis for understanding how to avoid AE transport that can undesirably redistribute current and cause fast-ion losses, and the measurements are being used to validate AE-induced transport models that use the critical gradient paradigm, giving greater confidence when applied to ITER.
- Published
- 2017
3. Fast-ion transport by Alfvén eigenmodes above a critical gradient threshold
- Author
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Heidbrink, WW, Collins, CS, Podestà, M, Kramer, GJ, Pace, DC, Petty, CC, Stagner, L, Van Zeeland, MA, White, RB, and Zhu, YB
- Subjects
Astronomical and Space Sciences ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Classical Physics ,Fluids & Plasmas - Abstract
Experiments on the DIII-D tokamak have identified how multiple simultaneous Alfvén eigenmodes (AEs) lead to overlapping wave-particle resonances and stochastic fast-ion transport in fusion grade plasmas [C. S. Collins et al., Phys. Rev. Lett. 116, 095001 (2016)]. The behavior results in a sudden increase in fast-ion transport at a threshold that is well above the linear stability threshold for Alfvén instability. A novel beam modulation technique [W. W. Heidbrink et al., Nucl. Fusion 56, 112011 (2016)], in conjunction with an array of fast-ion diagnostics, probes the transport by measuring the fast-ion flux in different phase-space volumes. Well above the threshold, simulations that utilize the measured mode amplitudes and structures predict a hollow fast-ion profile that resembles the profile measured by fast-ion Dα spectroscopy; the modelling also successfully reproduces the temporal response of neutral-particle signals to beam modulation. The use of different modulated sources probes the details of phase-space transport by populating different regions in phase space and by altering the amplitude of the AEs. Both effects modulate the phase-space flows.
- Published
- 2017
4. Control of power, torque, and instability drive using in-shot variable neutral beam energy in tokamaks
- Author
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Pace, DC, Collins, CS, Crowley, B, Grierson, BA, Heidbrink, WW, Pawley, C, Rauch, J, Scoville, JT, Van Zeeland, MA, and Zhu, YB
- Subjects
Affordable and Clean Energy ,neutral beam ,tokamak ,Alfven wave ,plasma control ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Fluids & Plasmas - Abstract
A first-ever demonstration of controlling power and torque injection through time evolution of neutral beam energy has been achieved in recent experiments at the DIII-D tokamak (Luxon 2002 Nucl. Fusion 42 614). Pre-programmed waveforms for the neutral beam energy produce power and torque inputs that can be separately and continuously controlled. Previously, these inputs were tailored using on/off modulation of neutral beams resulting in large perturbations (e.g. power swings of over 1 MW). The new method includes, importantly for experiments, the ability to maintain a fixed injected power while varying the torque. In another case, different beam energy waveforms (in the same plasma conditions) produce significant changes in the observed spectrum of beam ion-driven instabilities. Measurements of beam ion loss show that one energy waveform results in the complete avoidance of coherent losses due to Alfvénic instabilities. This new method of neutral beam operation is intended for further application in a variety of DIII-D experiments including those concerned with high-performance steady state scenarios, fast particle effects, and transport in the low torque regime. Developing this capability would provide similar benefits and improved plasma control for other magnetic confinement fusion facilities.
- Published
- 2017
5. Control of power, torque, and instability drive using in-shot variable neutral beam energy in tokamaks
- Author
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Diii-D Team, T, Pace, DC, Collins, CS, Crowley, B, Grierson, BA, Heidbrink, WW, Pawley, C, Rauch, J, Scoville, JT, Van Zeeland, MA, and Zhu, YB
- Subjects
neutral beam ,tokamak ,Alfven wave ,plasma control ,Fluids & Plasmas ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics - Abstract
A first-ever demonstration of controlling power and torque injection through time evolution of neutral beam energy has been achieved in recent experiments at the DIII-D tokamak (Luxon 2002 Nucl. Fusion 42 614). Pre-programmed waveforms for the neutral beam energy produce power and torque inputs that can be separately and continuously controlled. Previously, these inputs were tailored using on/off modulation of neutral beams resulting in large perturbations (e.g. power swings of over 1 MW). The new method includes, importantly for experiments, the ability to maintain a fixed injected power while varying the torque. In another case, different beam energy waveforms (in the same plasma conditions) produce significant changes in the observed spectrum of beam ion-driven instabilities. Measurements of beam ion loss show that one energy waveform results in the complete avoidance of coherent losses due to Alfvénic instabilities. This new method of neutral beam operation is intended for further application in a variety of DIII-D experiments including those concerned with high-performance steady state scenarios, fast particle effects, and transport in the low torque regime. Developing this capability would provide similar benefits and improved plasma control for other magnetic confinement fusion facilities.
- Published
- 2017
6. Fast-ion Dα spectrum diagnostic in the EAST
- Author
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Hou, YM, Wu, CR, Huang, J, Heidbrink, WW, von Hellermann, MG, Xu, Z, Jin, Z, Chang, JF, Zhu, YB, Gao, W, Chen, YJ, Lyu, B, Hu, RJ, Zhang, PF, Zhang, L, Wu, ZW, Yu, Y, and Ye, MY
- Subjects
Nuclear and Plasma Physics ,Synchrotrons and Accelerators ,Physical Sciences ,EAST Team ,Chemical Sciences ,Engineering ,Applied Physics ,Chemical sciences ,Physical sciences - Abstract
In toroidal magnetic fusion devices, fast-ion D-alpha diagnostic (FIDA) is a powerful method to study the fast-ion feature. The fast-ion characteristics can be inferred from the Doppler shifted spectrum of Dα light according to charge exchange recombination process between fast ions and probe beam. Since conceptual design presented in the last HTPD conference, significant progress has been made to apply FIDA systems on the Experimental Advanced Superconducting Tokamak (EAST). Both co-current and counter-current neutral beam injectors are available, and each can deliver 2-4 MW beam power with 50-80 keV beam energy. Presently, two sets of high throughput spectrometer systems have been installed on EAST, allowing to capture passing and trapped fast-ion characteristics simultaneously, using Kaiser HoloSpec transmission grating spectrometer and Bunkoukeiki FLP-200 volume phase holographic spectrometer coupled with Princeton Instruments ProEM 1024B eXcelon and Andor DU-888 iXon3 1024 CCD camera, respectively. This paper will present the details of the hardware descriptions and experimental spectrum.
- Published
- 2016
7. Validation of fast-ion D-alpha spectrum measurements during EAST neutral-beam heated plasmas
- Author
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Huang, J, Heidbrink, WW, von Hellermann, MG, Stagner, L, Wu, CR, Hou, YM, Chang, JF, Ding, SY, Chen, YJ, Zhu, YB, Jin, Z, Xu, Z, Gao, W, Wang, JF, Lyu, B, Zang, Q, Zhong, GQ, Hu, L, and Wan, B
- Subjects
Nuclear and Plasma Physics ,Information and Computing Sciences ,Applied Computing ,Physical Sciences ,EAST team ,Chemical Sciences ,Engineering ,Applied Physics ,Chemical sciences ,Physical sciences - Abstract
To investigate the fast ion behavior, a fast ion D-alpha (FIDA) diagnostic system has been installed on EAST. Fast ion features can be inferred from the Doppler shifted spectrum of Balmer-alpha light from energetic hydrogenic atoms. This paper will focus on the validation of FIDA measurements performed using MHD-quiescent discharges in 2015 campaign. Two codes have been applied to calculate the Dα spectrum: one is a Monte Carlo code, Fortran 90 version FIDASIM, and the other is an analytical code, Simulation of Spectra (SOS). The predicted SOS fast-ion spectrum agrees well with the measurement; however, the level of fast-ion part from FIDASIM is lower. The discrepancy is possibly due to the difference between FIDASIM and SOS velocity distribution function. The details will be presented in the paper to primarily address comparisons of predicted and observed spectrum shapes/amplitudes.
- Published
- 2016
8. Compact and multi-view solid state neutral particle analyzer arrays on National Spherical Torus Experiment-Upgrade
- Author
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Liu, D, Heidbrink, WW, Tritz, K, Fredrickson, ED, Hao, GZ, and Zhu, YB
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Nuclear and Plasma Physics ,Physical Sciences ,Chemical Sciences ,Engineering ,Applied Physics ,Chemical sciences ,Physical sciences - Abstract
A compact and multi-view solid state neutral particle analyzer (SSNPA) diagnostic based on silicon photodiode arrays has been successfully tested on the National Spherical Torus Experiment-Upgrade. The SSNPA diagnostic provides spatially, temporally, and pitch-angle resolved measurements of fast-ion distribution by detecting fast neutral flux resulting from the charge exchange (CX) reactions. The system consists of three 16-channel subsystems: t-SSNPA viewing the plasma mid-radius and neutral beam (NB) line #2 tangentially, r-SSNPA viewing the plasma core and NB line #1 radially, and p-SSNPA with no intersection with any NB lines. Due to the setup geometry, the active CX signals of t-SSNPA and r-SSNPA are mainly sensitive to passing and trapped particles, respectively. In addition, both t-SSNPA and r-SSNPA utilize three vertically stacked arrays with different filter thicknesses to obtain coarse energy information. The experimental data show that all channels are operational. The signal to noise ratio is typically larger than 10, and the main noise is x-ray induced signal. The active and passive CX signals are clearly observed on t-SSNPA and r-SSNPA during NB modulation. The SSNPA data also indicate significant losses of passing particles during sawteeth, while trapped particles are weakly affected. Fluctuations up to 120 kHz have been observed on SSNPA, and they are strongly correlated with magnetohydrodynamics instabilities.
- Published
- 2016
9. Interpretation of fast-ion signals during beam modulation experiments
- Author
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Heidbrink, WW, Collins, CS, Stagner, L, Zhu, YB, Petty, CC, and Van Zeeland, MA
- Subjects
fast-ions ,transport analysis ,phase-space transport ,perturbative experiments ,Alfven eigenmode instabilities ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Fluids & Plasmas - Abstract
Fast-ion signals produced by a modulated neutral beam are used to infer fast-ion transport. The measured quantity is the divergence of perturbed fast-ion flux from the phase-pace volume measured by the diagnostic, δ ⌈Since velocity-space transport often contributes to this divergence, the phase-space sensitivity of the diagnostic (or weight function) plays a crucial role in the interpretation of the signal. The source and sink make major contributions to the signal but their effects are accurately modelled by calculations that employ an exponential decay term for the sink. Recommendations for optimal design of a fast-ion transport experiment are given, illustrated by results from DIII-D measurements of fast-ion transport by Alfvn eigenmodes. The signal-to-noise ratio of the diagnostic, systematic uncertainties in the modeling of the source and sink, and the non-linearity of the perturbation all contribute to the error in δ ⌈.
- Published
- 2016
10. First results from solid state neutral particle analyzer on experimental advanced superconducting tokamak.
- Author
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Zhang, JZ, Zhu, YB, Zhao, JL, Wan, BN, Li, JG, and Heidbrink, WW
- Subjects
Applied Physics ,Engineering ,Physical Sciences ,Chemical Sciences - Abstract
Full function integrated, compact solid state neutral particle analyzers (ssNPA) based on absolute extreme ultraviolet silicon photodiode have been successfully implemented on the experimental advanced superconducting tokamak to measure energetic particle. The ssNPA system has been operated in advanced current mode with fast temporal and spatial resolution capabilities, with both active and passive charge exchange measurements. It is found that the ssNPA flux signals are increased substantially with neutral beam injection (NBI). The horizontal active array responds to modulated NBI beam promptly, while weaker change is presented on passive array. Compared to near-perpendicular beam, near-tangential beam brings more passive ssNPA flux and a broader profile, while no clear difference is observed on active ssNPA flux and its profile. Significantly enhanced intensities on some ssNPA channels have been observed during ion cyclotron resonant heating.
- Published
- 2016
11. Observation of Critical-Gradient Behavior in Alfvén-Eigenmode-Induced Fast-Ion Transport
- Author
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Collins, CS, Heidbrink, WW, Austin, ME, Kramer, GJ, Pace, DC, Petty, CC, Stagner, L, Van Zeeland, MA, White, RB, and Zhu, YB
- Subjects
DIII-D team ,Mathematical Sciences ,Physical Sciences ,Engineering ,General Physics - Abstract
Experiments in the DIII-D tokamak show that fast-ion transport suddenly becomes stiff above a critical threshold in the presence of many overlapping small-amplitude Alfvén eigenmodes (AEs). The threshold is phase-space dependent and occurs when particle orbits become stochastic due to resonances with AEs. Above threshold, equilibrium fast-ion density profiles are unchanged despite increased drive, and intermittent fast-ion losses are observed. Fast-ion Dα spectroscopy indicates radially localized transport of the copassing population at radii that correspond to the location of midcore AEs. The observation of stiff fast-ion transport suggests that reduced models can be used to effectively predict alpha profiles, beam ion profiles, and losses to aid in the design of optimized scenarios for future burning plasma devices.
- Published
- 2016
12. Development of an integrated energetic neutral particle measurement system on experimental advanced full superconducting tokamaka)
- Author
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Zhu, YB, Zhang, JZ, Qi, MZ, Xia, SB, Liu, D, Heidbrink, WW, Wan, BN, and Li, JG
- Subjects
Nuclear and Plasma Physics ,Synchrotrons and Accelerators ,Physical Sciences ,Chemical Sciences ,Engineering ,Applied Physics ,Chemical sciences ,Physical sciences - Abstract
Full function integrated, compact silicon photodiode based solid state neutral particle analyzers (ssNPA) have been developed for energetic particle (EP) relevant studies on the Experimental Advanced Superconducting Tokamak (EAST). The ssNPAs will be mostly operated in advanced current mode with a few channels to be operated in conventional pulse-counting mode, aiming to simultaneously achieve individually proved ultra-fast temporal, spatial, and spectral resolution capabilities. The design details together with considerations on EAST specific engineering realities and physics requirements are presented. The system, including a group of single detectors on two vertical ports and two 16-channel arrays on a horizontal port, can provide both active and passive charge exchange measurements. ssNPA detectors, with variable thickness of ultra thin tungsten dominated foils directly deposited on the front surface, are specially fabricated and utilized to achieve about 22 keV energy resolution for deuterium particle detection.
- Published
- 2014
13. Design of solid state neutral particle analyzer array for National Spherical Torus Experiment-Upgradea)
- Author
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Liu, D, Heidbrink, WW, Tritz, K, Zhu, YB, Roquemore, AL, and Medley, SS
- Subjects
Physical Sciences ,Chemical Sciences ,Engineering ,Applied Physics - Abstract
A new compact, multi-channel Solid State Neutral Particle Analyzer (SSNPA) diagnostic based on silicon photodiode array has been designed and is being fabricated for the National Spherical Torus Experiment-Upgrade (NSTX-U). The SSNPA system utilizes a set of vertically stacked photodiode arrays in current mode viewing the same plasma region with different filter thickness to obtain fast temporal resolution (∼120 kHz bandwidth) and coarse energy information in three bands of >25 keV, >45 keV, and >65 keV. The SSNPA system consists of 15 radial sightlines that intersect existing on-axis neutral beams at major radii between 90 and 130 cm, 15 tangential sightlines that intersect new off-axis neutral beams at major radii between 120 and 145 cm. These two subsystems aim at separating the response of passing and trapped fast ions. In addition, one photodiode array whose viewing area does not intersect any neutral beams is used to monitor passive signals produced by fast ions that charge exchange with background neutrals.
- Published
- 2014
14. Energetic ion transport by microturbulence is insignificant in tokamaksa)
- Author
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Pace, DC, Austin, ME, Bass, EM, Budny, RV, Heidbrink, WW, Hillesheim, JC, Holcomb, CT, Gorelenkova, M, Grierson, BA, McCune, DC, McKee, GR, Muscatello, CM, Park, JM, Petty, CC, Rhodes, TL, Staebler, GM, Suzuki, T, Van Zeeland, MA, Waltz, RE, Wang, G, White, AE, Yan, Z, Yuan, X, and Zhu, YB
- Subjects
Astronomical and Space Sciences ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Classical Physics ,Fluids & Plasmas - Abstract
Energetic ion transport due to microturbulence is investigated in magnetohydrodynamic-quiescent plasmas by way of neutral beam injection in the DIII-D tokamak [J. L. Luxon, Nucl. Fusion 42, 614 (2002)]. A range of on-axis and off-axis beam injection scenarios are employed to vary relevant parameters such as the character of the background microturbulence and the value of E b / T e, where Eb is the energetic ion energy and Te the electron temperature. In all cases, it is found that any transport enhancement due to microturbulence is too small to observe experimentally. These transport effects are modeled using numerical and analytic expectations that calculate the energetic ion diffusivity due to microturbulence. It is determined that energetic ion transport due to coherent fluctuations (e.g., Alfvén eigenmodes) is a considerably larger effect and should therefore be considered more important for ITER. © 2013 AIP Publishing LLC.
- Published
- 2013
15. Compact solid-state neutral particle analyzer in current mode.
- Author
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Zhu, YB, Bortolon, A, Heidbrink, WW, Celle, SL, and Roquemore, AL
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Applied Physics ,Engineering ,Physical Sciences ,Chemical Sciences - Abstract
Solid state neutral particle analyzer (ssNPA) arrays are operated in current mode on the DIII-D tokamak and the National Spherical Torus Experiment (NSTX). Compared with conventional pulse-counting NPAs, current-mode operation sacrifices energy resolution to obtain economical, high-bandwidth, pitch-angle resolved measurements. With the success from a new three-channel near-vertical-view current mode ssNPA on DIII-D, the apertures on an existing array on NSTX were expanded to increase the particle influx. The sightlines of both arrays intersect heating beams, enabling both active and passive charge exchange measurements. The spatial resolution at beam intersection is typically 5 cm on both devices. Directly deposited ultra-thin foils on the detector surface block stray photons below the energy of 1 keV and also set low energy threshold about 25 keV for deuterium particle detection. Oscillations in neutral flux produced by high frequency magnetohydrodynamics (MHD) instabilities are readily detected.
- Published
- 2012
16. Initial measurements of the DIII-D off-axis neutral beams
- Author
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Heidbrink, WW, Van Zeeland, MA, Grierson, BA, Muscatello, CM, Park, JM, Petty, CC, Prater, R, and Zhu, YB
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Fluids & Plasmas ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics - Abstract
Two of the eight neutral-beam sources on the DIII-D tokamak were modified to allow injection below the midplane. To validate off-axis beam performance, the various beams are injected sequentially into low-power plasmas that are optimized for accurate neutron, neutral-particle, fast-ion D-alpha and fast-ion pressure measurements. As expected, the fast-ion profile is broader with off-axis injection than with on-axis injection. The driven toroidal rotation also broadens with off-axis injection and the central fast-ion density is several times smaller. The number of trapped ions in the core depends sensitively on the pitch of the magnetic field lines. Comparisons with classical predictions agree with the measurements for some diagnostics but are discrepant for others. © 2012 IAEA, Vienna.
- Published
- 2012
17. Characterization of off-axis fishbones
- Author
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Heidbrink, WW, Austin, ME, Fisher, RK, García-Muñoz, M, Matsunaga, G, McKee, GR, Moyer, RA, Muscatello, CM, Okabayashi, M, Pace, DC, Shinohara, K, Solomon, WM, Strait, EJ, Van Zeeland, MA, and Zhu, YB
- Subjects
Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Other Physical Sciences ,Fluids & Plasmas - Abstract
Repetitive bursting instabilities with strong frequency chirping occur in high-beta, beam-heated plasmas with safety factor q > 1 in the DIII-D tokamak. Although the mode structures differ, in many ways, the off-axis fishbones are similar to the q = 1 fishbones first observed on the Poloidal Divertor Experiment (PDX). The modes are driven by energetic trapped ions at the fast-ion precession frequency. During a burst, the frequency changes most rapidly as the mode reaches its maximum amplitude. Larger amplitude bursts have larger growth rates and frequency chirps. Unlike PDX fishbones, the decay phase is highly variable and is usually shorter than the growth phase. Also, the waveform is highly distorted by higher harmonics during the latter portion of a burst. The radial mode structure alters its shape during the burst. Like PDX fishbones, the modes expel trapped ions in a 'beacon' with a definite phase relationship relative to the mode. Seven types of loss detectors measure the beacon. The losses scale linearly with mode amplitude. The neutron rate changes most rapidly at maximum mode amplitude but, depending on the loss diagnostic, the losses often peak a few cycles later. The non-ambipolar fast-ion losses cause a sudden change in toroidal rotation frequency across the entire plasma. In addition to an overall drop, the neutron signal oscillates in response to the wave. Unlike the beacon of lost particles, which maintains a fixed phase relative to the mode, the phase of the neutron oscillations steadily increases throughout the burst, with the greatest phase slippage occurring in the highly nonlinear phase near maximum mode amplitude. © 2011 IOP Publishing Ltd.
- Published
- 2011
18. Measurements and modeling of Alfvén eigenmode induced fast ion transport and loss in DIII-D and ASDEX Upgradea)
- Author
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Van Zeeland, MA, Heidbrink, WW, Fisher, RK, Muñoz, M García, Kramer, GJ, Pace, DC, White, RB, Aekaeslompolo, S, Austin, ME, Boom, JE, Classen, IGJ, da Graça, S, Geiger, B, Gorelenkova, M, Gorelenkov, NN, Hyatt, AW, Luhmann, N, Maraschek, M, McKee, GR, Moyer, RA, Muscatello, CM, Nazikian, R, Park, H, Sharapov, S, Suttrop, W, Tardini, G, Tobias, BJ, and Zhu, YB
- Subjects
Astronomical and Space Sciences ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Classical Physics ,Fluids & Plasmas - Abstract
Neutral beam injection into reversed magnetic shear DIII-D and ASDEX Upgrade plasmas produces a variety of Alfvénic activity including toroidicity-induced Alfvén eigenmodes and reversed shear Alfvén eigenmodes (RSAEs). These modes are studied during the discharge current ramp phase when incomplete current penetration results in a high central safety factor and increased drive due to multiple higher order resonances. Scans of injected 80 keV neutral beam power on DIII-D showed a transition from classical to AE dominated fast ion transport and, as previously found, discharges with strong AE activity exhibit a deficit in neutron emission relative to classical predictions. By keeping beam power constant and delaying injection during the current ramp, AE activity was reduced or eliminated and a significant improvement in fast ion confinement observed. Similarly, experiments in ASDEX Upgrade using early 60 keV neutral beam injection drove multiple unstable RSAEs. Periods of strong RSAE activity are accompanied by a large (peak δS n/Sn ≈ 60%) neutron deficit. Losses of beam ions modulated at AE frequencies were observed using large bandwidth energy and pitch resolving fast ion loss scintillator detectors and clearly identify their role in the process. Modeling of DIII-D loss measurements using guiding center following codes to track particles in the presence of ideal magnetohydrodynamic (MHD) calculated AE structures (validated by comparison to experiment) is able to reproduce the dominant energy, pitch, and temporal evolution of these losses. While loss of both co and counter current fast ions occurs, simulations show that the dominant loss mechanism observed is the mode induced transition of counter-passing fast ions to lost trapped orbits. Modeling also reproduces a coherent signature of AE induced losses and it was found that these coherent losses scale proportionally with the amplitude; an additional incoherent contribution scales quadratically with the mode amplitude. © 2011 American Institute of Physics.
- Published
- 2011
19. Off-axis fishbone-like instability and excitation of resistive wall modes in JT-60U and DIII-Da)
- Author
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Okabayashi, M, Matsunaga, G, deGrassie, JS, Heidbrink, WW, In, Y, Liu, YQ, Reimerdes, H, Solomon, WM, Strait, EJ, Takechi, M, Asakura, N, Budny, RV, Jackson, GL, Hanson, JM, La Haye, RJ, Lanctot, MJ, Manickam, J, Shinohara, K, and Zhu, YB
- Subjects
Astronomical and Space Sciences ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Classical Physics ,Fluids & Plasmas - Abstract
An energetic-particle (EP)-driven off-axis-fishbone-like mode (OFM) often triggers a resistive wall mode (RWM) in JT-60U and DIII-D devices, preventing long-duration high-βN discharges. In these experiments, the EPs are energetic ions (70-85 keV) injected by neutral beams to produce high-pressure plasmas. EP-driven bursting events reduce the EP density and the plasma rotation simultaneously. These changes are significant in high-βN low-rotation plasmas, where the RWM stability is predicted to be strongly influenced by the EP precession drift resonance and by the plasma rotation near the q = 2 surface (kinetic effects). Analysis of these effects on stability with a self-consistent perturbation to the mode structure using the MARS-K code showed that the impact of EP losses and rotation drop is sufficient to destabilize the RWM in low-rotation plasmas, when the plasma rotation normalized by Alfvén frequency is only a few tenths of a percent near the q = 2 surface. The OFM characteristics are very similar in JT-60U and DIII-D, including nonlinear mode evolution. The modes grow initially like a classical fishbone, and then the mode structure becomes strongly distorted. The dynamic response of the OFM to an applied n = 1 external field indicates that the mode retains its external kink character. These comparative studies suggest that an energetic particle-driven off-axis-fishbone-like mode is a new EP-driven branch of the external kink mode in wall-stabilized plasmas, analogous to the relationship of the classical fishbone branch to the internal kink mode. © 2011 American Institute of Physics.
- Published
- 2011
20. Transport of energetic ions due to sawteeth, Alfvén eigenmodes and microturbulence
- Author
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Pace, DC, Fisher, RK, García-Muñoz, M, Heidbrink, WW, McKee, GR, Murakami, M, Muscatello, CM, Nazikian, R, Park, JM, Petty, CC, Rhodes, TL, Staebler, GM, Van Zeeland, MA, Waltz, RE, White, RB, Yu, JH, Zhang, W, and Zhu, YB
- Subjects
Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Fluids & Plasmas - Abstract
Utilizing an array of new diagnostics and simulation/modelling techniques, recent DIII-D experiments have elucidated a variety of energetic ion transport behaviour in the presence of instabilities ranging from large-scale sawteeth to fine spatial scale microturbulence. Important new insights include sawteeth, such as those of the ITER baseline scenario, causing major redistribution of the energetic ion population; high levels of transport induced by low-amplitude Alfvén eigenmodes can be caused by the integrated effect of a large number of simultaneous modes; and microturbulence can contribute to the removal of alpha ash while having little effect on fusion alphas. This paper provides an overview of recent and upcoming results from the DIII-D Energetic Particles research programme. © 2011 IAEA, Vienna.
- Published
- 2011
21. Measurements of beam ion losses on DIII-D due to MHD instabilities
- Author
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Fisher, RK, Pace, DC, García-Muñoz, M, Boivin, RL, Fredrickson, ED, Heidbrink, WW, Muscatello, CM, Nazikian, R, Petty, CC, Van Zeeland, MA, and Zhu, YB
- Abstract
A new scintillator-based fast ion loss detector (FILD) has been installed on DIII-D with the time response (>100 kHz) needed to study energetic ion losses induced by Alfvén eigenmodes (AEs) and other MHD instabilities. Based on the design used on ASDEX Upgrade, the diagnostic measures the pitch angle and gyroradius of ion losses based on the position of the ions striking the 2D scintillator. For fast time response measurements, a beam splitter and fiberoptics couple a portion of the scintillator light to a photomultiplier. Initial results showing first orbit losses and energetic ion loss due to MHD instabilities are discussed.
- Published
- 2010
22. Scintillator-based diagnostic for fast ion loss measurements on DIII-Da)
- Author
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Fisher, RK, Pace, DC, García-Muñoz, M, Heidbrink, WW, Muscatello, CM, Van Zeeland, MA, and Zhu, YB
- Subjects
Physical Sciences ,Chemical Sciences ,Engineering ,Applied Physics - Abstract
A new scintillator-based fast ion loss detector has been installed on DIII-D with the time response (>100 kHz) needed to study energetic ion losses induced by Alfvén eigenmodes and other MHD instabilities. Based on the design used on ASDEX Upgrade, the diagnostic measures the pitch angle and gyroradius of ion losses based on the position of the ions striking the two-dimensional scintillator. For fast time response measurements, a beam splitter and fiberoptics couple a portion of the scintillator light to a photomultiplier. Reverse orbit following techniques trace the lost ions to their possible origin within the plasma. Initial DIII-D results showing prompt losses and energetic ion loss due to MHD instabilities are discussed.
- Published
- 2010
23. Modeling the response of a fast ion loss detector using orbit tracing techniques in a neutral beam prompt-loss study on the DIII-D tokamaka)
- Author
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Pace, DC, Fisher, RK, García-Muñoz, M, Darrow, DS, Heidbrink, WW, Muscatello, CM, Nazikian, R, Van Zeeland, MA, and Zhu, YB
- Subjects
Nuclear and Plasma Physics ,Physical Sciences ,Chemical Sciences ,Engineering ,Applied Physics ,Chemical sciences ,Physical sciences - Abstract
A numerical model describing the expected measurements of neutral beam prompt-losses by a newly commissioned fast ion loss detector (FILD) in DIII-D is presented. This model incorporates the well understood neutral beam deposition profiles from all eight DIII-D beamlines to construct a prompt-loss source distribution. The full range of detectable ion orbit phase space available to the FILD is used to calculate ion trajectories that overlap with neutral beam injection footprints. Weight functions are applied to account for the level of overlap between these detectable orbits and the spatial and velocity (pitch) properties of ionized beam neutrals. An experimental comparison is performed by firing each neutral beam individually in the presence of a ramping plasma current. Fast ion losses determined from the model are in agreement with measured losses.
- Published
- 2010
24. Phenomenology of energetic-ion loss from the DIII-D tokamak
- Author
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Zhu, YB, Heidbrink, WW, and Pickering, LD
- Subjects
Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Fluids & Plasmas - Abstract
Thin-foil Faraday collectors mounted near the midplane measure energetic-ion loss signals from the DIII-D tokamak. Modulation of the neutral beam sources shows that, under appropriate conditions, prompt losses from every beam line are observed. Prompt losses are usually larger when the plasma current or toroidal field is low. Enhanced losses occur during ion cyclotron heating. Instabilities that produce strong field perturbations at the edge also produce enhanced losses. © 2010 IAEA, Vienna Printed in the UK & the USA.
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- 2010
25. Fast ion loss diagnostics on DIII-D
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Fisher, RK, Boivin, RL, Garcia-Munoz, M, Heidbrink, WW, Pace, DC, Van Zeeland, MA, and Zhu, YB
- Abstract
New fluctuation and fast ion diagnostics on DIII-D have resulted in the first experimental measurements of the spatial structure of Alfvén eigenmodes (AEs) and their impact on the radial profile of confined beam ions. This paper describes fast ion loss diagnostics designed to help understand how AE's and other instabilities perturb the fast ion orbits and degrade their confinement.
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- 2009
26. Motion estimation techniques for digital TV: a review and a new contribution
- Author
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Fisher, RK, Van Zeeland, MA, Pace, DC, Heidbrink, WW, Muscatello, CM, Zhu, YB, and García-Muñoz, M
- Subjects
Artificial Intelligence and Image Processing ,Biomedical Engineering ,Electrical and Electronic Engineering - Abstract
A new scintillator-based fast ion loss detector has been installed on DIII-D with the time response (>100 kHz) needed to study energetic ion losses induced by Alfvén eigenmodes and other MHD instabilities. Based on the design used on ASDEX Upgrade, the diagnostic measures the pitch angle and gyroradius of ion losses based on the position of the ions striking the two-dimensional scintillator. For fast time response measurements, a beam splitter and fiberoptics couple a portion of the scintillator light to a photomultiplier. Reverse orbit following techniques trace the lost ions to their possible origin within the plasma. Initial DIII-D results showing prompt losses and energetic ion loss due to MHD instabilities are discussed. © 2010 American Institute of Physics. [doi:10.1063/1.3490020] © 1995 IEEE
- Published
- 1995
27. Pharmacokinetics and bioavailability study of two ondansetron oral soluble film formulations in fasting healthy male Chinese volunteers
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Zhu YB, Zhang Q, Zou JJ, Wan M, Zhao Z, and Zhu JR
- Subjects
Therapeutics. Pharmacology ,RM1-950 - Abstract
Yubing Zhu,1 Qian Zhang,1 Jianjun Zou,2 Meng Wan,1 Zheng Zhao,1 Junrong Zhu1 1Department of Pharmacy, 2Laboratory of Clinical Pharmacology, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China Background: Ondansetron oral soluble film is designed to be applied on top of the tongue without requiring water to aid dissolution or swallowing, which is especially fitting for nausea and vomiting patients.Purpose: This study was conducted to compare the bioavailability of two 8 mg ondansetron oral soluble film formulations.Patients and methods: This randomized, open-label, two-period crossover study was performed under fasting conditions. A total of ten eligible subjects were randomly assigned at a 1:1 ratio to receive a single 8 mg dose of the test and reference ondansetron oral soluble film formulations, followed by a 1-week washout period and administration of the alternate formulation. The concentrations of ondansetron were assayed using an liquid chromatograph-mass spectrometer/mass spectrometer (LC-MS/MS) method. For analysis of pharmacokinetic properties, including the peak concentration of Tmax (Cmax), AUC from time 0 (baseline) to t hours (AUC0–t), and AUC from baseline to infinity (AUC0–∞), blood samples were obtained at intervals over the 24-hour period after studying drug administration. Tolerability was assessed by monitoring vital signs and laboratory tests (hematology, blood biochemistry, hepatic function, and urinalysis) and by questioning subjects about adverse events.Results: The mean (standard derivation [SD]) relative bioavailability was 96.5 (23.7%). The 90% confidence intervals (CIs) for the log-transformed ratios of Cmax and AUC0–t were 84.71%–103.28% and 91.38%–108.60%, respectively (P>0.05). Similar results were found for the data without log-transformation. No statistically significant differences were found based on analysis of variance. No significant adverse events occurred or were reported during the study.Conclusion: As the 90% CIs based on the differences between the test and reference formulation were within the 80%–125% range for both the Cmax and AUC0–t, we concluded that the two formulations were bioequivalent with respect to the rate or the extent of absorption. Both formulations are well tolerated. Keywords: ondansetron, oral soluble film, LC-MS/MS, bioequivalence
- Published
- 2015
28. Unidirectional and Selective Proton Transport in Artificial Heterostructured Nanochannels with Nano-to-Subnano Confined Water Clusters
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Li, X, Zhang, H, Yu, H, Xia, J, Zhu, YB, Wu, HA, Hou, J, Lu, J, Ou, R, Easton, CD, Selomulya, C ; https://orcid.org/0000-0001-5506-0308, Hill, MR, Jiang, L, Wang, H, Li, X, Zhang, H, Yu, H, Xia, J, Zhu, YB, Wu, HA, Hou, J, Lu, J, Ou, R, Easton, CD, Selomulya, C ; https://orcid.org/0000-0001-5506-0308, Hill, MR, Jiang, L, and Wang, H
- Abstract
The construction of biological proton channel analogues has attracted substantial interest owing to their wide potential in separation of ions, sensing, and energy conversion. Here, metal–organic framework (MOF)/polymer heterogeneous nanochannels are presented, in which water molecules are confined to disordered clusters in the nanometer-sized polymer regions and to ordered chains with unique molecular configurations in the 1D sub-1-nm porous MOF regions, to realize unidirectional, fast, and selective proton transport properties, analogous to natural proton channels. Given the nano-to-subnano confined water junctions, experimental proton conductivities in the polymer-to-MOF direction of the channels are much higher than those in the opposite direction, showing a high rectification up to 500 and one to two orders of magnitude enhancement compared to the conductivity of proton transport in bulk water. The channels also show a good proton selectivity over other cations. Theoretical simulations further reveal that the preferential and fast proton conduction in the nano-to-subnano channel direction is attributed to extremely low energy barriers for proton transport from disordered to ordered water clusters. This study opens a novel approach to regulate ion permeability and selectivity of artificial ion channels.
- Published
- 2020
29. Diagnostic values of microRNA-31 in peripheral blood mononuclear cells for pediatric pulmonary tuberculosis in Chinese patients
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Jianqing Xu, Wei Zhang, Jian Wang, Han Yf, and Zhu Yb
- Subjects
Male ,medicine.medical_specialty ,Adolescent ,Gastroenterology ,Peripheral blood mononuclear cell ,Pulmonary tuberculosis ,Internal medicine ,microRNA ,Genetics ,medicine ,Humans ,Child ,Tuberculosis, Pulmonary ,Molecular Biology ,business.industry ,Age Factors ,Infant, Newborn ,NF-kappa B ,Infant ,Diagnostic marker ,General Medicine ,Prognosis ,MicroRNAs ,ROC Curve ,Case-Control Studies ,Child, Preschool ,Immunology ,Normal children ,Leukocytes, Mononuclear ,Cytokines ,Female ,Tumor necrosis factor alpha ,business ,Biomarkers - Abstract
We investigated the diagnostic values of microRNA-31 in peripheral blood mononuclear cells (PBMCs) for pediatric pulmonary tuberculosis in Chinese patients. Sixty-five children with TB were selected for this study, which was conducted at the Department of Infectious Diseases People's Hospital of Laiwu City between December 2013 and December 2014. Sixty healthy children, selected in parallel, served as the control group. Real-time PCR was used to detect miR-31 expression in PBMCs. Serum levels of IL-6, TNF-α, NF-κB, and IFN-γ was detected by ELISA. ROC curve was employed to evaluate the diagnostic value of miR-31 in pediatric TB. Results show that expression of miRNA-31 in pediatric TB patients was significantly lower than that in normal children (0.48 ± 0.15 vs 1.23 ± 0.36, P < 0.05). By contrast, serum levels of the innate immune response cytokines, IL-6, TNF-α, NF-κB, and IFN-γ, were significantly higher in pediatric TB patients compared with normal children (P < 0.05). Furthermore, miRNA-31 expression was negatively correlated with serum levels of IL-6 (t = 69.91, P < 0.001), TNF-α (t = 10.96, P < 0.001), NF-κB (t = 39.94, P < 0.001), and IFN -γ (t = 37.94, P < 0.001). The cut-off threshold of miR-31 for pediatric TB diagnosis is 0.835 with a sensitivity of 98.5% and a specificity of 86.7%. Therefore, miR-31 has the potential to be a diagnostic marker in pediatric TB patients.
- Published
- 2015
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30. Fast ion D-alpha measurements using a bandpass-filtered system on EAST.
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Zhang, J, Huang, J, Chang, JF, Wu, CR, Heidbrink, WW, Salewski, M, Madsen, B, Zhu, YB, von Hellermann, MG, Gao, W, Xu, Z, Wan, B, Zhang, J, Huang, J, Chang, JF, Wu, CR, Heidbrink, WW, Salewski, M, Madsen, B, Zhu, YB, von Hellermann, MG, Gao, W, Xu, Z, and Wan, B
- Abstract
Based on the charge exchange reaction between fast ions and a neutral beam, fast ion features can be inferred from the spectrum of Doppler-shifted Balmer-alpha light from energetic hydrogenic atoms. In order to study the interaction between instabilities and fast-ion transport, recently we extended the fast ion D-alpha (FIDA) measurements by using a combination of a bandpass filter and a photomultiplier tube (PMT) (f-FIDA). A bandpass filter selects the desired spectral band from 651 nm to 654 nm before detection by the PMT. Preliminary data from the EAST tokamak show that the active signals have been detected from reneutralized beam ions along the vertical and tangential viewing geometries. The details will be presented in this paper to primarily address the specifications and performance of f-FIDA hardware components and preliminary FIDA measurements.
- Published
- 2018
31. Fast-ion Dαspectrum diagnostic in the EAST
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Hou, YM, Wu, CR, Huang, J, Heidbrink, WW, Von Hellermann, MG, Xu, Z, Jin, Z, Chang, JF, Zhu, YB, Gao, W, Chen, YJ, Lyu, B, Hu, RJ, Zhang, PF, Zhang, L, Wu, ZW, Yu, Y, and Ye, MY
- Abstract
© 2016 Author(s). In toroidal magnetic fusion devices, fast-ion D-alpha diagnostic (FIDA) is a powerful method to study the fast-ion feature. The fast-ion characteristics can be inferred from the Doppler shifted spectrum of Dαlight according to charge exchange recombination process between fast ions and probe beam. Since conceptual design presented in the last HTPD conference, significant progress has been made to apply FIDA systems on the Experimental Advanced Superconducting Tokamak (EAST). Both co-current and counter-current neutral beam injectors are available, and each can deliver 2-4 MW beam power with 50-80 keV beam energy. Presently, two sets of high throughput spectrometer systems have been installed on EAST, allowing to capture passing and trapped fast-ion characteristics simultaneously, using Kaiser HoloSpec transmission grating spectrometer and Bunkoukeiki FLP-200 volume phase holographic spectrometer coupled with Princeton Instruments ProEM 1024B eXcelon and Andor DU-888 iXon3 1024 CCD camera, respectively. This paper will present the details of the hardware descriptions and experimental spectrum.
- Published
- 2016
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32. Splicing mutation of a gene within the Duchenne muscular dystrophy family
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Shi-chao Wei, Luo Jw, Zheng Xy, Hu D, Zhu Yb, and Gan Jh
- Subjects
musculoskeletal diseases ,0301 basic medicine ,Proband ,Male ,congenital, hereditary, and neonatal diseases and abnormalities ,Heterozygote ,Duchenne muscular dystrophy ,RNA Splicing ,Biology ,Dystrophin ,03 medical and health sciences ,symbols.namesake ,Exon ,Genetics ,medicine ,Missense mutation ,Humans ,Child ,Molecular Biology ,Sanger sequencing ,Point mutation ,Intron ,General Medicine ,Exons ,medicine.disease ,Introns ,Pedigree ,Muscular Dystrophy, Duchenne ,030104 developmental biology ,RNA splicing ,Mutation ,symbols ,Female - Abstract
The aim of this study was to identify the mutation site and phenotype of the Duchenne muscular dystrophy (DMD) gene in a DMD family. The DMD gene is by far the largest known gene in humans. Up to 34% of the point mutations reported to date affect splice sites of the DMD gene. However, no hotspot mutation has been reported. Capture sequencing of second-generation exons was used to investigate the DMD gene in a proband. Sanger sequencing was performed for mutation scanning in eight family members. Scale-invariant feature transform and PolyPhen were applied to predict the functional impact of protein mutations. A hemizygous splicing mutation IVS44ds +1G-A (c.6438 +1G>A) that induces abnormal splicing variants during late transcription and produces abnormal proteins was located in intron 44. Four missense mutations (p.Arg2937Gln, p.Asp882Gly, p.Lys2366Gln, and p.Arg1745His) that are known multiple-polymorphic sites were found in the coding region of the DMD gene. A heterozygous c.6438+1G>A mutation was detected on the X chromosome of the proband's mother and maternal grandmother.
- Published
- 2016
33. This title is unavailable for guests, please login to see more information.
- Author
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Hou, YM, Hou, YM, Wu, CR, Huang, J, Heidbrink, WW, von Hellermann, MG, Xu, Z, Jin, Z, Chang, JF, Zhu, YB, Gao, W, Chen, YJ, Lyu, B, Hu, RJ, Zhang, PF, Zhang, L, Wu, ZW, Yu, Y, Ye, MY, Hou, YM, Hou, YM, Wu, CR, Huang, J, Heidbrink, WW, von Hellermann, MG, Xu, Z, Jin, Z, Chang, JF, Zhu, YB, Gao, W, Chen, YJ, Lyu, B, Hu, RJ, Zhang, PF, Zhang, L, Wu, ZW, Yu, Y, and Ye, MY
- Published
- 2016
34. Scintillator-based diagnostic for fast ion loss measurements on DIII-Da)
- Author
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Fisher, RK, Van Zeeland, MA, Pace, DC, Heidbrink, WW, Muscatello, CM, Zhu, YB, and García-Muñoz, M
- Subjects
Physics::Instrumentation and Detectors ,Physics::Plasma Physics - Abstract
A new scintillator-based fast ion loss detector has been installed on DIII-D with the time response (>100 kHz) needed to study energetic ion losses induced by Alfvén eigenmodes and other MHD instabilities. Based on the design used on ASDEX Upgrade, the diagnostic measures the pitch angle and gyroradius of ion losses based on the position of the ions striking the two-dimensional scintillator. For fast time response measurements, a beam splitter and fiberoptics couple a portion of the scintillator light to a photomultiplier. Reverse orbit following techniques trace the lost ions to their possible origin within the plasma. Initial DIII-D results showing prompt losses and energetic ion loss due to MHD instabilities are discussed. © 2010 American Institute of Physics. [doi:10.1063/1.3490020] © 1995 IEEE
- Published
- 1995
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35. Development of a patient-reported outcome scale for stable chronic obstructive pulmonary disease and its clinical applicability
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Zhu, YB, primary
- Published
- 2011
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36. Logistic regression analysis on relationships between traditional Chinese medicine constitutional types and overweight or obesity
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Zhu, YB, primary
- Published
- 2010
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37. Relationships between constitutional types of traditional Chinese
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Zhu, YB, primary
- Published
- 2010
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38. Induced expression of B7-H4 on the surface of lung cancer cell by the tumor-associated macrophages: A potential mechanism of immune escape.
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Chen C, Qu QX, Shen Y, Mu CY, Zhu YB, Zhang XG, and Huang JA
- Published
- 2012
39. Towards automatical tumor segmentation in radiomics: a comparative analysis of various methods and radiologists for both region extraction and downstream diagnosis.
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Yu Y, Li GF, Tan WX, Qu XY, Zhang T, Hou XY, Zhu YB, Ma ZY, Yang L, Gao Y, Yu M, Yue C, Zhou Z, Yang Y, Yan LF, and Cui GB
- Subjects
- Humans, Diagnosis, Differential, Tomography, X-Ray Computed methods, Artificial Intelligence, Female, Radiologists, Radiographic Image Interpretation, Computer-Assisted methods, Male, Radiomics, Lung Neoplasms diagnostic imaging, Lung Neoplasms pathology
- Abstract
Objective: By discussing the difference, stability and classification ability of tumor contour extracted by artificial intelligence and doctors, can a more stable method of tumor contour extraction be obtained?, Methods: We propose a novel framework for the automatic segmentation of lung tumor contours and the differential diagnosis of downstream tasks. This framework integrates four key modules: tumor segmentation, extraction of radiomic features, feature selection, and the development of diagnostic models for clinical applications. Using this framework, we conducted a study involving a cohort of 1,429 patients suspected of lung cancer. Four automatic segmentation methods (RNN, UNET, WFCM, and SNAKE) were evaluated against manual segmentation performed by three radiologists with varying levels of expertise. We further studied the consistency of radiomic features extracted from these methods and evaluates their diagnostic performance across three downstream tasks: benign vs. malignant classification, lung adenocarcinoma infiltration, and lung nodule density classification., Results: The Dice coefficient of RNN is the highest among the four automatic segmentation methods (0.803 > 0.751, 0.576, 0.560), and all P < 0.05. In the consistency comparison of the seven contour-extracted radiomic features, that the features extracted by RNN and S1 (the senior radiologist) showed the highest similarity which was higher than the other automatic segmentation methods and doctors with low seniority. In all three downstream tasks, the radiomic features extracted from RNN segmentation contours showed the highest diagnostic discrimination. In the classification of benign and malignant nodules, the RNN method performed slightly better than the S1 method, with an AUC of 0.840 ± 0.01 and 0.824 ± 0.015, respectively, and significantly better than the other five methods. Similarly, the RNN method had an AUC value of 0.946 in lung adenocarcinoma infiltration, and a kappa value of 0.729 in lung nodule density classification, both of which were better than the other six methods., Conclusions: Our findings suggest that AI-driven tumor segmentation methods can enhance clinical decision-making by providing reliable and reproducible results, ultimately emphasizing the auxiliary role of automated tumor contouring in clinical practice. The findings will have important implications for the application of radiomics in clinical practice., Competing Interests: Declarations. Ethics approval and consent to participate: All the procedures were implemented based on the principles of the Declaration of Helsinki. Ethical approval was obtained from the Ethics Committee of Tangdu Hospital (No. K202108-18). Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)
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- 2025
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40. Reconstruction of a microbial TNT deep degradation system and its mechanism for reshaping microecology.
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Yang X, Zhu YB, Zhao SP, and Xi HL
- Abstract
This study is the first to use synthetic biological omics technology to analyze the molecular mechanism underlying deep degradation of TNT, to construct an artificial transformation system to create engineered Escherichia coli bacteria, and to use Bacillus subtilis as an expression host to explore the mechanism driving the reshaping of the deep degradation platform on microecology. Nitroreductase family protein, 2-oxoacid:acceptor oxidoreductase, NADPH-cytochrome P450 reductase, monooxygenase, ring-cleaving dioxygenase, and RraA family protein significantly participated in the reduction-hydroxylation-ring opening cleavage of TNT, achieving deep transformation of TNT to produce pyruvic acid and other products that entered the cellular metabolic cycle. The key toxic metabolic pathways of TNT, 2,4-diamino-6-nitrotoluene, 2,4,6-triaminotoluene, and 2,4,6-trihydroxytoluene are pantothenate and CoA biosynthesis. The engineered bacteria that impart TNT deep degradation ability regulate and optimize lipid, sugar, and amino acid metabolism to withstand stress. Engineered B. subtilis bacteria occupy ecological niches after repairing TNT-contaminated soil and water bodies while simultaneously recruiting a variety of microorganisms to reshape and positively regulate microecology. Key drivers for reshaping and optimization of microecological functions include ABC transporters and C/N/P/S functional cycles, together with a significant concomitant upregulation of the metabolic cycle of basic carbohydrates, nucleotides, and amino acids in the microecology., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)
- Published
- 2025
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41. Eleutherococcus senticosus Alleviates Aristolochic-Acid-Induced Acute Kidney Damage by Inhibiting the NLRP3/IL-1β Signaling Pathway in Mice.
- Author
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Zhang JH, Gao MZ, Chen Q, Chen T, Ruan DD, Wu M, Huang FM, Luo JW, Zhu YB, and Chen L
- Abstract
Eleutherococcus senticosus (ES) exerts various pharmacological effects, including renoprotection in a rat model of renal ischemia-reperfusion injury. However, the mechanisms of these effects remain unclear. Therefore, we investigated the effects and mechanisms of ES on aristolochic acid (AA)-induced acute kidney injury in mice. The experimental mice were divided into the control group, the model group (AA-induced acute kidney injury model), the model + ES group ( Eleutherococcus senticosus boiled-free granules treated by gavage for two weeks), the model + fasudil group (fasudil administered intraperitoneally for three days), and the model + ES + fasudil group. After AA intervention in normal mice, the expression of ASC and NLRP3 and the levels of IL-1 β , IL-18, and TNF- α were significantly elevated in mouse renal tissues (P < 0.05). However, AA-induced renal dysfunction was ameliorated by both ES and fasudil, which was confirmed by the decrease in serum creatinine and blood urea nitrogen levels, as well as by renal histopathological abnormalities such as renal tubule dilation and tubular formation. In addition, the inflammatory response of AA-induced renal inflammation was inhibited by both ES and fasudil, and the expression of ASC and NLRP3 and the levels of IL-1 β , IL-18, and TNF- α were significantly higher in mouse renal tissues after the treatment of either ES or fasudil (P < 0.05). ES may be a potential treatment agent for aristolochic-acid-triggered nephropathy, with inhibition of the NLRP3/IL-1 β as one plausible underlying mechanism., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)
- Published
- 2025
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42. scImmOmics: a manually curated resource of single-cell multi-omics immune data.
- Author
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Li YY, Zhou LW, Qian FC, Fang QL, Yu ZM, Cui T, Dong FJ, Cai FH, Yu TT, Li LD, Wang QY, Zhu YB, Tang HF, Hu BY, and Li CQ
- Subjects
- Humans, Animals, Immune System metabolism, Databases, Genetic, Mice, Sequence Analysis, RNA, Genomics methods, Software, Multiomics, Single-Cell Analysis methods
- Abstract
Single-cell sequencing technology has enabled the discovery and characterization of subpopulations of immune cells with unique functions, which is critical for revealing immune responses under healthy or disease conditions. Efforts have been made to collect and curate single-cell RNA sequencing (scRNA-seq) data, yet an immune-specific single-cell multi-omics atlas with harmonized metadata is still lacking. Here, we present scImmOmics (https://bio.liclab.net/scImmOmics/home), a manually curated single-cell multi-omics immune database constructed based on high-quality immune cells with known immune cell labels. Currently, scImmOmics documents >2.9 million cell-type labeled immune cells derived from seven single-cell sequencing technologies, involving 131 immune cell types, 47 tissues and 4 species. To ensure data consistency, we standardized the nomenclature of immune cell types and presented them in a hierarchical tree structure to clearly describe the lineage relationships within the immune system. scImmOmics also provides comprehensive immune regulatory information, including T-cell/B-cell receptor sequencing clonotype information, cell-specific regulatory information (e.g. gene/chromatin accessibility/protein/transcription factor states within known cell types, cell-to-cell communication and co-expression networks) and immune cell responses to cytokines. Collectively, scImmOmics is a comprehensive and valuable platform for unraveling the heterogeneity and diversity of immune cells and elucidating the specific regulatory mechanisms at the single-cell level., (© The Author(s) 2024. Published by Oxford University Press on behalf of Nucleic Acids Research.)
- Published
- 2025
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43. Sarcopenic obesity is significantly associated with poorer overall survival after liver transplantation: a systematic review and meta-analysis.
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Huang HB, Zhu YB, and Yu DX
- Abstract
Background: Sarcopenia has been shown to worsen survival after liver transplantation. However, it remains unclear whether coexisting sarcopenia and obesity, so-called sarcopenic obesity (SO), may also synergistically increase their adverse effects. This meta-analysis aimed to evaluate whether pre-transplant SO independently predicts survival in this population., Methods: We conducted this study according to the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. The PubMed, Embase, Web of Science, Wanfang, CNKI, and Cochrane databases were searched up to 15 October 2023, for studies with any study design evaluating the relationship between SO and post-transplant survival in patients undergoing liver transplantation. We used ROBINS-E to assess the study quality. The primary outcome was all-cause mortality at any length of follow-up. We calculated pooled odds risks (ORs) or hazard risks (HRs) with 95% confidence intervals (CIs). Heterogeneity was quantified with I
2 statistics. Subgroup analyses and publication bias evaluations were also conducted., Results: We included nine cohort studies with 2,416 patients. These studies were moderate to high quality. Pre-liver transplant patients commonly experience SO, with a mean prevalence as high as 34%. Overall, patients with SO exhibited a significantly higher overall mortality than patients without SO, as demonstrated by pooled studies using both univariate analysis [HR = 1.76, 95%C 1.33-2.33, p < 0.0001] and multivariate analysis (HR = 2.33, 95%CI 1.34-4.04, p = 0.003). Similar results were also found when comparing patients with or without SO at 1, 3, and 5 years of follow-up (OR = 1.86, 95%CI 1.22-2.83; OR = 1.83, 95%CI: 1.27-2.64; and OR = 1.54, 95% CI 1.02-2.34, respectively). In addition, subgroup analysis based on studies that reported HRs of both sarcopenia and SO indicated both had independent negative effects on post-transplant survival., Conclusion: Our meta-analysis showed that SO occurs frequently in liver transplant patients. SO is associated with an increased risk of mortality in such patient populations., Systematic Review Registration: https://doi.org/10.37766/inplasy2024.2.0069 [inplasy2024.2.0069]., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Huang, Zhu and Yu.)- Published
- 2024
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44. Functional Carbon Springs Enabled Dynamic Tunable Microwave Absorption and Thermal Insulation.
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Wang ZY, Li ZC, Li B, Shi AF, Zhang L, Zhu YB, Ye F, and Yu SH
- Abstract
Electromagnetic (EM) wave pollution and thermal damage pose serious hazards to delicate instruments. Functional aerogels offer a promising solution by mitigating EM interference and isolating heat. However, most of these materials struggle to balance thermal protection with microwave absorption (MA) efficiency due to a previously unidentified conflict between the optimizing strategies of the two properties. Herein, this study reports a solution involving the design of a carbon-based aerogel called functional carbon spring (FCS). Its unique long-range lamellar multi-arch microstructure enables tunable MA performance and excellent thermal insulation capability. Adjusting compression strain from 0% to 50%, the adjustable effective absorption bandwidth (EAB) spans up to 13.4 GHz, covering 84% of the measured frequency spectrum. Notably, at 75% strain, the EAB drops to 0 GHz, demonstrating a novel "on-off" switchability for MA performance. Its ultralow vertical thermal conductivity (12.7 mW m
-1 K-1 ) and unique anisotropic heat transfer mechanism endow FCS with superior thermal protection effectiveness. Numerical simulations demonstrate that FCS outperforms common honeycomb structures and isotropic porous aerogels in thermal management. Furthermore, an "electromagnetic-thermal" dual-protection material database is established, which intuitively demonstrates the superiority of the solution. This work contributes to the advancement of multifunctional MA materials with significant potential for practical applications., (© 2024 Wiley‐VCH GmbH.)- Published
- 2024
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45. Simultaneously Strengthening and Toughening All-Natural Structural Materials via 3D Nanofiber Network Interfacial Design.
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Yang HB, Zhao X, Wang Q, Ruan YH, Liu ZX, Yue X, Zhu YB, Wu HA, Guan QF, and Yu SH
- Abstract
Constructing structural materials from sustainable raw materials is considered an efficient way to reduce the potential threat posed by plastics. Nevertheless, challenges remain regarding combining excellent mechanical and thermal properties, especially the balance of strength and toughness. Here, we report a 3D nanofiber network interfacial design strategy to strengthen and toughen all-natural structural materials simultaneously. The introduced protonated chitosan at the interface between the surface oxidized 3D nanonetwork of bacterial cellulose forms the interfacial interlocking structure of nanonetworks, achieving a robust physical connection and providing enough physical contact sites for chemical crosslinking. The obtained sustainable structural material successfully integrates excellent mechanical and thermal properties on the nanoscale of cellulose nanofibers, such as light weight, high strength, and superior thermal expansion coefficient. The relationship between structural design and comprehensive mechanical property improvement is analyzed in detail, providing a universal perspective to design sustainable high-performance structural materials from nanoscale building blocks., (© 2024 Wiley-VCH GmbH.)
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- 2024
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46. Low-dose trimethoprim-sulfamethoxazole treatment for Pneumocystis pneumonia: a systematic review and meta-analysis.
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Huang HB, Zhu YB, and Yu DX
- Abstract
Background: The recommended standard treatment for Pneumocystis jirovecii pneumonia (PJP) is high-dose trimethoprim-sulfamethoxazole (TMP-SMX) (15-20 mg/kg/d TMP). However, the standard regimen may cause a high incidence of dose-related adverse events (AEs). Therefore, we aimed to conduct a systematic review and meta-analysis to evaluate the efficacy and safety of low-dose TMP-SMX regimens (<15 mg/kg/d of TMP) compared with the standard regimen in patients with PJP., Methods: We searched PubMed, Embase, and the Cochrane database for relevant articles from inception to 10 March 2024. Studies were included if they focused on PJP patients receiving a low-dose TMP-SMX regimen compared with a standard regimen. The primary outcome was mortality. We assessed study quality and performed subgroup analysis and sensitivity analysis to explore potential heterogeneity among the included studies., Results: Seven studies were included. Overall, the low-dose regimen significantly reduced the risk of mortality (odds ratio [OR] = 0.49; 95% CI, 0.30-0.80; I
2 = 16%; P = 004). This finding was confirmed in further sensitivity and subgroup analyses. The low-dose regimen also significantly reduced total AEs (OR = 0.43; 95% CI, 0.29-0.62; I2 = 0%; P < 0.0001), and improved the incidence of most specific AEs (ORs ranged from 0.13 to 0.89). In addition, the low-dose regimen had significantly more patients completing the initial regimen ( P = 0.002), fewer patients requiring dose reductions ( P = 0.04), and almost significantly fewer patients requiring a switch to a second-line regimen ( P = 0.06)., Conclusion: The limited available evidence suggests that a low-dose TMP-SMX regimen significantly reduced mortality and total AEs in PJP patients. Thus, it is one of the potentially promising therapies to PJP and more high-quality and multi-center randomized trials should be conducted in the future., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Huang, Zhu and Yu.)- Published
- 2024
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47. Reassessment of palliative surgery in conversion therapy of previously unresectable hepatocellular carcinoma: Two case reports and review of literature.
- Author
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Zhu YB, Qin JY, Zhang TT, Zhang WJ, and Ling Q
- Abstract
Background: Most patients with hepatocellular carcinoma (HCC) have lost the opportunity for direct surgery at the time of diagnosis. Transarterial chemoembolization (TACE) combined with immune checkpoint inhibitors or tyrosine kinase inhibitors (TKI) can partially transform some unresectable HCC and improve the prognosis effectively. However, based on the promising prospects of combined targeted and immunotherapy for the effective treatment of HCC, the positive role of palliative surgery in the conversion treatment of advanced HCC urgently needs further intensive re-assessment., Case Summary: In this study, we describe two successful cases of "conversion therapy for unresectable HCC" achieved mainly by palliative surgery combined with TACE plus immunotherapy and TKIs. A 48-year-old patient with newly diagnosed HCC, presenting with a 6-cm mass in the segment VII/VIII of the right liver with multiple intrahepatic metastases, could not undergo one-stage radical surgical resection. He underwent palliative surgery with radiofrequency of metastatic lesions and the palliative resection of the primary mass, and received subsequent TACE treatments twice in the early postoperative period (2 weeks and 6 weeks), in addition to targeted and immune combination therapy with sintilimab injection and oral lenvatinib. No evidence of recurrence was observed during the 11-month follow-up period after surgery. The other patient was a 47-year-old patient with massive HCC (18 cm × 15 cm × 4.5 cm) in the left liver with severe cirrhosis. The left portal branch was occluded and a tumor thrombus formed, and the tumor partly involved the middle hepatic vein. The patient underwent palliative surgery of left hemihepatectomy (including resection of the middle hepatic vein) for HCC, followed by three TACE procedures and oral TKIs 2 weeks after surgery. Six months later, the re-examination via computed tomography revealed no tumour activity in the remaining right liver, while magnetic resonance imaging revealed slight local tumor enhancement in the caudate lobe of the liver considered, TACE was performed once again, and during the next follow-up of 10 months did not reveal new intrahepatic lesions or distant metastases., Conclusion: These cases demonstrate that the addition of palliative surgery to conversion therapy in a selected population with a high tumor burden could benefit patients with initially unresectable HCC., Competing Interests: Conflict-of-interest statement: All authors stated that there was no potential conflict of interest., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)
- Published
- 2024
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48. Mechanically Stable and Damage Resistant Freestanding Ultrathin Silver Nanowire Films with Closely Packed Crossed-Lamellar Structure.
- Author
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Zhang SC, Gao HL, Zhang L, Zhu YB, Wu YD, Liu JW, Mao LB, Feng M, Dong L, Pan Z, Meng XS, Lu Y, and Yu SH
- Abstract
One-dimensional (1D) functional nanowires are widely used as nanoscale building blocks for assembling advanced nanodevices due to their unique functionalities. However, previous research has mainly focused on nanowire functionality, while neglecting the structural stability and damage resistance of nanowire assemblies, which are critical for the long-term operation of nanodevices. Biomaterials achieve excellent mechanical stability and damage resistance through sophisticated structural design. Here, we successfully prepared a mechanically stabilized monolamella silver nanowire (Ag NW) film, based on a facile bubble-mediated assembly and nondestructive transfer strategy with the assistance of a porous mixed cellulose ester substrate, inspired by the hierarchical structure of biomaterial. Owing to the closely packed arrangement of Ag NWs combined with their weak interfaces, the monolamellar Ag NW film can be transferred to arbitrary substrates without damage. Furthermore, freestanding multilamellar Ag NW films with impressive damage resistance can be obtained from the monolamellar Ag NW film, through the introduction of bioinspired closely packed crossed-lamellar (CPCL) structure. This CPCL structure maximizes intra- and interlamellar interactions among Ag NWs ensuring efficient stress transfer and uniform electron transport, resulting in excellent mechanical durability and stable electrical properties of the multilamellar Ag NW films., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Co-published by University of Science and Technology of China and American Chemical Society.)
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- 2024
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49. Key genomes, transcriptomes, proteins, and metabolic factors involved in the detoxification/tolerance of TNT and its intermediates by bacteria in anaerobic/aerobic environments.
- Author
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Yang X, Yin ML, Zhu YB, Zhao SP, and Xi HL
- Subjects
- Anaerobiosis, Genome, Bacterial, Aerobiosis, Bacteria metabolism, Bacteria genetics, Transcriptome, Biodegradation, Environmental, Trinitrotoluene metabolism, Bacterial Proteins genetics, Bacterial Proteins metabolism
- Abstract
Novel microbial strains capable of efficient degradation of TNT and typical intermediates (2-ADNT and 4-ADNT) in aerobic/anaerobic environment were screened and isolated from ammunition-contaminated sites. The key genomes, transcriptomes, proteins, and metabolic factors for microbial detoxification/tolerance to pollutants in anaerobic and aerobic environments were analyzed for the first time. The bacterial genome, which is rich in metabolism and environmental information-processing functional genes, provides transcriptional and translational-related proteins for detoxifying/tolerating pollutants. At the transcriptional level, bacteria significantly expressed genes related to inositol phosphate metabolism for regulating membrane transport, maintaining the cytoskeleton, and signal transduction. At the protein level, genes involved in antioxidation, fat metabolism, sugar synthesis/degradation, and pyruvate metabolism were significantly expressed. At the metabolic level, riboflavin metabolism, which regulates membrane integrity, protects against oxidative stress, and maintains the sugar-protein-fat balance, showed significant responses. Bacteria simultaneously regulate amino acid metabolism, carbohydrate metabolism, and N/P/S cycles to maintain homeostatic cellular energy supplies. The key pathway for pollutant degradation in bacteria is nitrotoluene degradation. The molecular mechanism of bacterial tolerance to pollutants involves the regulation of oxidative phosphorylation and basic cycle pathways to maintain gene transcription, protein translation, and metabolic cycles., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
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50. The value of computed tomography angiography for evaluation of left atrial enlargement in patients with persistent atrial fibrillation.
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Lin FF, Chen Q, Wu QY, Li SJ, Zhu YB, Tang Y, Xue YJ, Luo JW, Li ZA, and Chen HY
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- Humans, Female, Male, Middle Aged, Aged, Reproducibility of Results, Atrial Function, Left, Atrial Remodeling, Retrospective Studies, Cardiomegaly diagnostic imaging, Multidetector Computed Tomography, Pulmonary Veins diagnostic imaging, Pulmonary Veins physiopathology, Atrial Fibrillation diagnostic imaging, Atrial Fibrillation diagnosis, Atrial Fibrillation physiopathology, Computed Tomography Angiography, Heart Atria diagnostic imaging, Heart Atria physiopathology, Predictive Value of Tests
- Abstract
Background: The post-processing technology of CTA offers significant advantages in evaluating left atrial enlargement (LAE) in patients with persistent atrial fibrillation (PAF). This study aims to identify parameters for rapidly and accurately diagnosing LAE in patients with PAF using CT cross-sections., Methods: Left atrial pulmonary venous (PV) CT was performed to 300 PAF patients with dual-source CT, and left atrial volume (LAV), left atrial anteroposterior diameter (LAD1), left atrial transverse diameter (LAD2), and left atrial area (LAA) were measured in the ventricular end systolic (ES) and middle diastolic (MD). LA index (LAI) = LA parameter/body surface area (BSA). Left atrial volume index (LAVI
ES ) > 77.7 ml/m2 was used as the reference standard for the LAE diagnosis., Results: 227 patients were enrolled in the group, 101 (44.5%) of whom had LAE. LAVES and LAVMD (r = 0.983), LAVIES and LAVIMD (r = 0.984), LAAES and LAVIES (r = 0.817), LAAMD and LAVIES (r = 0.814) had strong positive correlations. The area under curve (AUC) showed that all measured parameters were suitable for diagnosing LAE, and the diagnostic efficacy was compared as follows: LAA/LAAI> LAD> the relative value index of LAD, LAD2> LAD1. LAA and LAAI demonstrated comparable diagnostic efficacy, with LAA being more readily available than LAAI., Conclusions: The axial LAA measured by CTA can be served as a parameter for the rapid and accurate diagnosis of LAE in patients with PAF., (© 2024. The Author(s).)- Published
- 2024
- Full Text
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