1
|
Wang LY, Liu ZY, Yin JJ, Yan LW, Wang PP, Shi YS, Zhang Y, Zhao HM. [Analysis of the common respiratory viruses in children with acute respiratory infection in a hospital in Lanzhou City from 2021 to 2022]. Zhonghua Yu Fang Yi Xue Za Zhi 2023; 57:1635-1639. [PMID: 37859383 DOI: 10.3760/cma.j.cn112150-20230518-00391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 10/21/2023]
Abstract
To explore the situation of 8 common respiratory pathogens in children with acute respiratory infection (ARI) from 2021 to 2022.The retrospective study selected 8 710 ARI patients from September 2021 to August 2022 in the Maternal and Child Health Hospital of Gansu Province as the study object, patients aged 0 to 17 years old, including 5 048 male children and 3 662 female children. Indirect immunofluorescence was used to detect 8 common respiratory pathogens, including influenza virus A (FluA), influenza virus B (FluB), parainfluenza virus (PIV), respiratory syncytial virus (RSV), adenovirus (ADV), Mycoplasma pneumoniae (MP), Chlamydia pneumoniae (CP), and Coxsackie virus group B (CoxB) IgM antibodies. χ2 test was used to analyze the results. The results showed that 1 497 of 8 710 children with ARI were positive, with a positive rate of 17.19%. The detection rate of MP among 8 common respiratory pathogens was 11.34%, accounting for 66.0%, followed by FluB, CoxB, PIV, RSV, ADV, FluA and CP, accounting for 13.83%, 9.55%, 6.01%, 2.61%, 1.47%, 0.40% and 0.13%, respectively. Respiratory tract viruses (FluA, FluB, RSV, ADV, PIV, CoxB) accounted for 33.86%.There were significant differences in the detection rates of PIV, ADV and MP among children of different genders (χ2=6.814, 5.154 and 17.784, P<0.05). The detection rate of school-age children (6-17 years old) was the highest, accounting for 33.27% (184/553). The detection rates of 8 common respiratory pathogens in patients with ARI were higher in spring and winter and lower in summer and autumn. To sum up, from 2021 to 2022, MP and FluB infection were dominant in ARI patients in our hospital. The peak period of 8 common respiratory pathogens was in spring and winter. The physical examination rate of 8 common respiratory pathogens in ARI patients aged 6-17 years old was the highest.
Collapse
Affiliation(s)
- L Y Wang
- Department of Clinical Laboratory, Gansu Provincial Maternal and Child Health Care Hospital, Lanzhou 730050, China
| | - Z Y Liu
- Department of Clinical Laboratory, Gansu Provincial Maternal and Child Health Care Hospital, Lanzhou 730050, China
| | - J J Yin
- Department of Clinical Laboratory, Gansu Provincial Maternal and Child Health Care Hospital, Lanzhou 730050, China
| | - L W Yan
- Department of Clinical Laboratory, Gansu Provincial Maternal and Child Health Care Hospital, Lanzhou 730050, China
| | - P P Wang
- Department of Clinical Laboratory, Gansu Provincial Maternal and Child Health Care Hospital, Lanzhou 730050, China
| | - Y S Shi
- Department of Clinical Laboratory, Gansu Provincial Maternal and Child Health Care Hospital, Lanzhou 730050, China
| | - Y Zhang
- Department of Clinical Laboratory, Gansu Provincial Maternal and Child Health Care Hospital, Lanzhou 730050, China
| | - H M Zhao
- Department of Clinical Laboratory, Gansu Provincial Maternal and Child Health Care Hospital, Lanzhou 730050, China
| |
Collapse
|
2
|
Zhao P, Zhang C, Dong XM, Yan LW, Mi LY, Li YJ, Kang JC, Wang J. [Mechanism of Proliferation and Apoptosis of Acute Promyelocytic Leukemia Cell Line NB4 Induced by TPA]. Zhongguo Shi Yan Xue Ye Xue Za Zhi 2023; 31:1296-1302. [PMID: 37846675 DOI: 10.19746/j.cnki.issn.1009-2137.2023.05.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 10/18/2023]
Abstract
OBJECTIVE To investigate the effect of phorbol-12-myristate-13-ace-tate (TPA) on the proliferation and apoptosis of acute promyelocytic leukemia cell line NB4 and its molecular mechanism. METHODS The effect of different concentrations of TPA on the proliferation of NB4 cells at different time points was detected by CCK-8 assay. The morphological changes of NB4 cells were observed by Wright-Giemsa staining. The cell cycle and apoptosis of NB4 cells after TPA treatment were detected by flow cytometry. The mRNA expressions of NB4 cells after TPA treatment were analyzed by high-throughput microarray analysis and real-time quantitative PCR. Western blot was used to detect the protein expression of CDKN1A, CDKN1B, CCND1, MYC, Bax, Bcl-2, c-Caspase 3, c-Caspase 9, PIK3R6, AKT and p-AKT. RESULTS Compared with the control group, TPA could inhibit the proliferation of NB4 cells, induce the cells to become mature granulocyte-monocyte differentiation, and also induce cell G1 phase arrest and apoptosis. Differentially expressed mRNAs were significantly enriched in PI3K/AKT pathway. TPA treatment could increase the mRNA levels of CCND1, CCNA1, and CDKN1A, while decrease the mRNA level of MYC. It could also up-regulate the protein levels of CDKN1A, CDKN1B, CCND1, Bax, c-Caspase 3, c-Caspase 9, and PIK3R6, while down-regulate MYC, Bcl-2, and p-AKT in NB4 cells. CONCLUSION TPA induces NB4 cell cycle arrest in G1 phase and promotes its apoptosis by regulating PIK3/AKT signaling pathway.
Collapse
Affiliation(s)
- Pan Zhao
- School of Public Health, Gansu University of Chinese Medicine, Lanzhou 730000, Gansu Province, China
- Clinical Laboratory Center of Gansu Provincial Maternity and Child Care Hospital, Lanzhou 730050, Gansu Province, China
| | - Chong Zhang
- Clinical Laboratory Center of Gansu Provincial Maternity and Child Care Hospital, Lanzhou 730050, Gansu Province, China
| | - Xue-Mei Dong
- Clinical Laboratory Center of Gansu Provincial Maternity and Child Care Hospital, Lanzhou 730050, Gansu Province, China
| | - Lu-Wei Yan
- Clinical Laboratory Center of Gansu Provincial Maternity and Child Care Hospital, Lanzhou 730050, Gansu Province, China
- The First Clinical Medical College of Lanzhou University, Lanzhou 730000, Gansu Province, China
| | - Le-Yuan Mi
- Clinical Laboratory Center of Gansu Provincial Maternity and Child Care Hospital, Lanzhou 730050, Gansu Province, China; The First Clinical Medical College of Lanzhou University, Lanzhou 730000, Gansu Province, China
| | - Ya-Jiao Li
- Clinical Laboratory Center of Gansu Provincial Maternity and Child Care Hospital, Lanzhou 730050, Gansu Province, China
| | - Jia-Chao Kang
- School of Public Health, Gansu University of Chinese Medicine, Lanzhou 730000, Gansu Province, China
| | - Jing Wang
- School of Public Health, Gansu University of Chinese Medicine, Lanzhou 730000, Gansu Province, China E-mail:
| |
Collapse
|
3
|
Yan LW, Yin JJ, Hu XY, Wang LY, Dong XM, Sun ZP, Zhang C, Jin FL. Diagnostic Value of Serum Amyloid A and C-Reactive Protein in Children with Mycoplasma pneumoniae Infection. Clin Lab 2023; 69. [PMID: 36912318 DOI: 10.7754/clin.lab.2023.221116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2023]
|
4
|
Liu L, He XF, Yu DL, Shi ZB, Lu J, Xia F, Zheng DL, Zhang N, He XX, Wei YL, Zang LG, Yang ZC, Yan LW, Liu Y, Yang QW. Visible wide-angle view imaging system for the first plasma on the HL-2M tokamak. Appl Opt 2021; 60:3211-3216. [PMID: 33983221 DOI: 10.1364/ao.418903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 03/11/2021] [Indexed: 06/12/2023]
Abstract
The wide-angle view imaging system, in terms of a tangential view diagnostic with field of view (FOV) of 56.8° and a downward-looking diagnostic from the top of the machine with FOV of 94.7°, has been newly constructed for the first plasma of the HL-2M tokamak achieved in December 2020. Its mission in this stage is to monitor the plasma evolution during its startup, sustainment, and disruption in the visible spectral range as well as the plasma-wall interaction. For the latter ultrawide view diagnostic, nearly three-quarters of the divertor region and half the area of the inner wall are in the view range. Both the diagnostics are characterized by a similar optical structure, i.e., the light emission from the plasma is collected by a front-end lens and transferred through an imaging fiber bundle to the camera. This optical structure is suitable for application in the complex tokamak environment mainly because the fiber bundle is flexible. Photos of glow discharges are acquired prior to the first plasma for testing the FOVs in the vacuum vessel. The spatial resolution is ∼4mm for the tangential view diagnostic and ∼10mm for the downward-looking diagnostic. The temporal resolutions, ranging from 90 to 360 Hz by changing the region of interest or binning acquisition mode of the color camera, are applied to record the plasma evolutions and/or dust creation events during the first plasma campaign.
Collapse
|
5
|
Yu JB, Zhang HJ, Yan LW, Chang F, Jia ZW, Yang XR. [microRNA-16-5p targeted tetraspanin 15 gene to inhibit the proliferation, migration and invasion of osteosarcoma cell through phospoinositide 3-kinase/protein kinase B signaling pathway]. Zhonghua Yi Xue Za Zhi 2020; 100:1668-1675. [PMID: 32486604 DOI: 10.3760/cma.j.cn112137-20191101-02376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To study the effects of miR-16-5p on proliferation, migration and invasion of osteosarcoma cells and its mechanism. Methods: Quantitative polymerase chain reaction (qPCR) and Western blotting were used to detect the mRNA and protein expression of miR-16-5p and TSPAN15 in human normal osteoblasts hFOB 1.19 and osteosarcoma cells MG63, Saos2 and HOS. The miR-16-5p or si-TSPAN15 was transfected into MG63 cells to observe its role in cell proliferation, migration and invasion. Cell proliferation was measured with MTT assay, cell migration and invasion were examined by Transwell, and the protein expression of CyclinD1, matrix metalloproteinase 2 (MMP-2), MMP-9, tetraspanin 15 (TSPAN15), phospha-tidylinositol3-kinase(p-PI3K) and phospha-protein kinase B(p-AKT) were determined by using Western blotting. The starbase website prediction combined with dual luciferase gene reporter assay was performed to analyze the targeting relationship between miR-16-5p and TSPAN15. miR-16-5p and pcDNA-TSPAN1 were co-transfected to assess the effect of high expression of TSPAN15 on overexpression of miR-16-5p-induced proliferation, migration and invasion of MG63 cells. Data comparison between the two groups was performed by using t test. Results: Compared with hFOB 1.19 cells (1.00±0.12), the expression of miR-16-5p was significantly decreased in MG63, Saos2 and HOS cells (0.32±0.05, 0.40±0.04, 0.45±0.06, respectively)(F=156.204, P<0.05), and TSPAN15 mRNA and protein levels were greatly increased (F=71.718, 110.350, both P<0.05). Overexpression of miR-16-5p obviously reduced the expression of CyclinD1, MMP-2, MMP-9 protein, cell viability, cell migration and invasion (F=150.136,117.228, 154.971, 89.479, 98.373, 130.880, all P<0.05) in MG63 cells. Knockdown of TSPAN15 greatly reduced CyclinD1, MMP-2, MMP-9 protein levels, cell survival rate, cell migration, and invasion number (F=93.206, 107.030, 109.326, 115.625, 146.113, 139.300, all P<0.05). Overexpression of miR-16-5p markedly decreased the expression of p-PI3K and p-AKT protein in MG63 cells (F=156.755, 181.419, both P<0.05). miR-16-5p targeted to regulate the expression of TSPAN15. High expression of TSPAN15 partially reversed the inhibitory effect of miR-16-5p on TSPAN15, CyclinD1, MMP-2, MMP-9, p-PI3K, p-AKT protein expression, cell viability, cell migration number and invasion number in MG63 cells. Conclusion: miR-16-5p inhibits the proliferation, migration and invasion of osteosarcoma cells by targeting the TSPAN15 gene and regulating the PI3K/AKT signaling pathway.
Collapse
Affiliation(s)
- J B Yu
- Orthopedics Departmentof Shanxi Provincial People's Hospital, Taiyuan 030012, China
| | - H J Zhang
- Department of Nursing Surgery of Shanxi Health Vocational College, Taiyuan 030607, China
| | - L W Yan
- Orthopedics Department of Xinzhou People's Hospital, Xinzhou 034000, China
| | - F Chang
- Orthopedics Departmentof Shanxi Provincial People's Hospital, Taiyuan 030012, China
| | - Z W Jia
- Orthopedics Departmentof Shanxi Provincial People's Hospital, Taiyuan 030012, China
| | - X R Yang
- Department of Physiology, Shanxi Medical University, Taiyuan 030604, China
| |
Collapse
|
6
|
He XX, Yu DL, Yan LW, Liu L, Chen WJ, Wei YL, He XF, Ma Q, Shi ZB, Liu Y, Yang QW, Xu M, Duan XR. Fast charge exchange recombination spectroscopy on HuanLiu-2A tokamak. Rev Sci Instrum 2020; 91:053504. [PMID: 32486744 DOI: 10.1063/1.5143454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Accepted: 04/30/2020] [Indexed: 06/11/2023]
Abstract
A Fast Charge eXchange Recombination Spectroscopy (CXRS) diagnostic with eight radial channels has been implemented on a HuanLiu-2A (HL-2A) tokamak with a time resolution of up to 10 kHz monitoring helium II spectra or 1 kHz monitoring carbon VI spectra. The crucial aspects of the fast CXRS are to improve the spectral intensity and the acquisition frequency. The spectral intensity has been greatly enhanced by customized fiber bundles. The main boost in optimizing the acquisition frequency is achieved by binning more pixel rows of the charge coupled device (CCD) representing one radial channel and by reducing the effective image area of the CCD. Consequently, the sawtooth oscillations of ion temperature and rotation velocity are continuously observed for the first time in the HL-2A tokamak.
Collapse
Affiliation(s)
- X X He
- Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041, China
| | - D L Yu
- Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041, China
| | - L W Yan
- Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041, China
| | - L Liu
- Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041, China
| | - W J Chen
- Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041, China
| | - Y L Wei
- Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041, China
| | - X F He
- Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041, China
| | - Q Ma
- College of Physics and Optoelectronics Technology, Baoji University of Arts and Sciences, Baoji, Shanxi 721016, China
| | - Z B Shi
- Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041, China
| | - Yi Liu
- Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041, China
| | - Q W Yang
- Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041, China
| | - M Xu
- Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041, China
| | - X R Duan
- Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041, China
| |
Collapse
|
7
|
Chen WJ, Yu DL, Yan LW, Yuan BS, He XX, Liu L, Wei YL, Wang J, Shi ZB, Liu Y, Yang QW. Note: Real-time wavelength matching system designed for the motional Stark effect polarimeter on HL-2A tokamak. Rev Sci Instrum 2018; 89:126103. [PMID: 30599558 DOI: 10.1063/1.5049613] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 11/12/2018] [Indexed: 06/09/2023]
Abstract
A 7-channel motional Stark effect diagnostic based on dual photo-elastic modulators is installed and operated routinely for rather low beam energy and magnetic field on the HL-2A tokamak, with a spatial resolution of ∼3 cm and a temporal resolution of 10 ms. The instrument observes the σ component of the full energy Dα from the first or the fourth ion source of a neutral beam injector. However, the change in beam energy during a discharge causes variation of the Doppler shift with the maximum of 1 Å, which leads to the polarization fraction drop from 30%-40% to 10% and then makes the signal-to-noise ratio of the system become very poor. Therefore, a real-time wavelength matching system is designed to promote polarization fraction. The beam emission spectra are filtered by using a monochrometer in real time. And a narrowband filter is tilted by using an absolutely calibrated rotator through beam energy in order to make sure that the deviation of wavelength matching is less than 0.1 Å.
Collapse
Affiliation(s)
- W J Chen
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - D L Yu
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - L W Yan
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - B S Yuan
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - X X He
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - L Liu
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - Y L Wei
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - J Wang
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - Z B Shi
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - Y Liu
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - Q W Yang
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| |
Collapse
|
8
|
Zhao KJ, Nagashima Y, Diamond PH, Dong JQ, Itoh K, Itoh SI, Yan LW, Cheng J, Fujisawa A, Inagaki S, Kosuga Y, Sasaki M, Wang ZX, Wei L, Huang ZH, Yu DL, Hong WY, Li Q, Ji XQ, Song XM, Huang Y, Liu Y, Yang QW, Ding XT, Duan XR. Synchronization of Geodesic Acoustic Modes and Magnetic Fluctuations in Toroidal Plasmas. Phys Rev Lett 2016; 117:145002. [PMID: 27740841 DOI: 10.1103/physrevlett.117.145002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Indexed: 06/06/2023]
Abstract
The synchronization of geodesic acoustic modes (GAMs) and magnetic fluctuations is identified in the edge plasmas of the HL-2A tokamak. Mesoscale electric fluctuations (MSEFs) having components of a dominant GAM, and m/n=6/2 potential fluctuations are found at the same frequency as that of the magnetic fluctuations of m/n=6/2 (m and n are poloidal and toroidal mode numbers, respectively). The temporal evolutions of the MSEFs and the magnetic fluctuations clearly show the frequency entrainment and the phase lock between the GAM and the m/n=6/2 magnetic fluctuations. The results indicate that GAMs and magnetic fluctuations can transfer energy through nonlinear synchronization. Such nonlinear synchronization may also contribute to low-frequency zonal flow formation, reduction of turbulence level, and thus confinement regime transitions.
Collapse
Affiliation(s)
- K J Zhao
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - Y Nagashima
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Kasuga koen 6-1, 816-8580, Japan
| | - P H Diamond
- Center for Momentum Transport and Flow Organization, University of California at San Diego, California, San Diego 92093, USA
| | - J Q Dong
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
- Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027, China
| | - K Itoh
- National Institute for Fusion Science, Toki 509-5292, Japan
| | - S-I Itoh
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Kasuga koen 6-1, 816-8580, Japan
| | - L W Yan
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - J Cheng
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - A Fujisawa
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Kasuga koen 6-1, 816-8580, Japan
| | - S Inagaki
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Kasuga koen 6-1, 816-8580, Japan
| | - Y Kosuga
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Kasuga koen 6-1, 816-8580, Japan
| | - M Sasaki
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Kasuga koen 6-1, 816-8580, Japan
| | - Z X Wang
- School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024, China
| | - L Wei
- School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024, China
| | - Z H Huang
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - D L Yu
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - W Y Hong
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - Q Li
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - X Q Ji
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - X M Song
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - Y Huang
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - Yi Liu
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - Q W Yang
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - X T Ding
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - X R Duan
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| |
Collapse
|
9
|
Yu DL, Wei YL, Liu L, Cao JY, Ma Q, Chen WJ, Liu Y, Yan LW, Yang QW, Duan XR. Progress of neutral-beam-aided diagnostics on the HL-2A tokamak. Rev Sci Instrum 2014; 85:11E402. [PMID: 25430309 DOI: 10.1063/1.4886419] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A 32/64-channel Charge eXchange Recombination Spectroscopy (CXRS) and a 7-channel motional Stark effect (MSE) polarimeter have been developed on the HL-2A tokamak. To extract the maximum time resolution of the system, the incidence fibers of the spectrometer are pitch-controlled; and the double-slit fiber bundle can increase the spatial channels with one charge-coupled device detector. The ion temperature and plasma rotation with time and spatial resolutions up to 5 ms and 1 cm are obtained. Sawtooth oscillation, transition from intermediate phase (I phase) to high confinement mode (H mode) can be clearly observed by the CXRS. The spectrometer can be utilized as the main component of the MSE polarimeter, which can effectively overcome the weak Stark effect. The pitch angles of magnetic field are obtained for 7 spatial points covering 24 cm along major radius with time resolution of 40 ms.
Collapse
Affiliation(s)
- D L Yu
- Southwestern Institute of Physics, Chengdu 610041, China
| | - Y L Wei
- Southwestern Institute of Physics, Chengdu 610041, China
| | - L Liu
- Southwestern Institute of Physics, Chengdu 610041, China
| | - J Y Cao
- Southwestern Institute of Physics, Chengdu 610041, China
| | - Q Ma
- Southwestern Institute of Physics, Chengdu 610041, China
| | - W J Chen
- Southwestern Institute of Physics, Chengdu 610041, China
| | - Y Liu
- Southwestern Institute of Physics, Chengdu 610041, China
| | - L W Yan
- Southwestern Institute of Physics, Chengdu 610041, China
| | - Q W Yang
- Southwestern Institute of Physics, Chengdu 610041, China
| | - X R Duan
- Southwestern Institute of Physics, Chengdu 610041, China
| |
Collapse
|
10
|
Wei YL, Yu DL, Liu L, Ida K, von Hellermann M, Cao JY, Sun AP, Ma Q, Chen WJ, Liu Y, Yan LW, Yang QW, Duan XR, Liu Y. High spatial and temporal resolution charge exchange recombination spectroscopy on the HL-2A tokamak. Rev Sci Instrum 2014; 85:103503. [PMID: 25362389 DOI: 10.1063/1.4897186] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A 32/64-channel charge exchange recombination spectroscopy (CXRS) diagnostic system is developed on the HL-2A tokamak (R = 1.65 m, a = 0.4 m), monitoring plasma ion temperature and toroidal rotation velocity simultaneously. A high throughput spectrometer (F/2.8) and a pitch-controlled fiber bundle enable the temporal resolution of the system up to 400 Hz. The observation geometry and an optimized optic system enable the highest radial resolution up to ∼1 cm at the plasma edge. The CXRS system monitors the carbon line emission (C VI, n = 8-7, 529.06 nm) whose Doppler broadening and Doppler shift provide ion temperature and plasma rotation velocity during the neutral beam injection. The composite CX spectral data are analyzed by the atomic data and analysis structure charge exchange spectroscopy fitting (ADAS CXSFIT) code. First experimental results are shown for the case of HL-2A plasmas with sawtooth oscillations, electron cyclotron resonance heating, and edge transport barrier during the high-confinement mode (H-mode).
Collapse
Affiliation(s)
- Y L Wei
- Southwestern Institute of Physics, Chengdu 610041, China
| | - D L Yu
- Southwestern Institute of Physics, Chengdu 610041, China
| | - L Liu
- Southwestern Institute of Physics, Chengdu 610041, China
| | - K Ida
- National Institute for Fusion Science, Toki 509-5292, Japan
| | - M von Hellermann
- ITER Diagnostic Team, IO, Route de Vinon sur Verdon, 13115 St Paul lez Durance, France
| | - J Y Cao
- Southwestern Institute of Physics, Chengdu 610041, China
| | - A P Sun
- Southwestern Institute of Physics, Chengdu 610041, China
| | - Q Ma
- Southwestern Institute of Physics, Chengdu 610041, China
| | - W J Chen
- Southwestern Institute of Physics, Chengdu 610041, China
| | - Yi Liu
- Southwestern Institute of Physics, Chengdu 610041, China
| | - L W Yan
- Southwestern Institute of Physics, Chengdu 610041, China
| | - Q W Yang
- Southwestern Institute of Physics, Chengdu 610041, China
| | - X R Duan
- Southwestern Institute of Physics, Chengdu 610041, China
| | - Yong Liu
- Southwestern Institute of Physics, Chengdu 610041, China
| |
Collapse
|
11
|
Yu DL, Wei YL, Xia F, Cao JY, Chen CY, Liu L, Chen WJ, Ji XQ, Liu Y, Yan LW, Yang QW, Duan XR. The motional Stark effect polarimeter in the HL-2A tokamak. Rev Sci Instrum 2014; 85:053508. [PMID: 24880370 DOI: 10.1063/1.4875257] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A 7-channel motional Stark effect polarimeter based on four polarizers and a spectrometer has been developed in the HL-2A tokamak, which is the first time successful utilizing this kind of polarimeter on a tokamak. The accuracy of the angle can reach ±0.25° in the calibration experiments. Pilot experiments of measuring the magnetic pitch angle have been successfully carried out in the weak motional Stark effect plasma discharge with toroidal magnetic field of ~1.3 T and beam energy of ~25 keV/amu. The pitch angles of magnetic field are obtained for 7 spatial points covering 24 cm along major radius with time resolution of 40 ms; the profiles of safety factor are obtained by combining with the Equilibrium and Reconstruction Fitting Code. The core value of safety factor (q) is less than 1 during the sawtooth oscillation and the position of q = 1 surface is well consistent with the results measured by soft X-ray array.
Collapse
Affiliation(s)
- D L Yu
- Southwestern Institute of Physics, Chengdu, Sichuan 610041, China
| | - Y L Wei
- Southwestern Institute of Physics, Chengdu, Sichuan 610041, China
| | - F Xia
- Southwestern Institute of Physics, Chengdu, Sichuan 610041, China
| | - J Y Cao
- Southwestern Institute of Physics, Chengdu, Sichuan 610041, China
| | - C Y Chen
- Southwestern Institute of Physics, Chengdu, Sichuan 610041, China
| | - L Liu
- Southwestern Institute of Physics, Chengdu, Sichuan 610041, China
| | - W J Chen
- Southwestern Institute of Physics, Chengdu, Sichuan 610041, China
| | - X Q Ji
- Southwestern Institute of Physics, Chengdu, Sichuan 610041, China
| | - Y Liu
- Southwestern Institute of Physics, Chengdu, Sichuan 610041, China
| | - L W Yan
- Southwestern Institute of Physics, Chengdu, Sichuan 610041, China
| | - Q W Yang
- Southwestern Institute of Physics, Chengdu, Sichuan 610041, China
| | - X R Duan
- Southwestern Institute of Physics, Chengdu, Sichuan 610041, China
| |
Collapse
|
12
|
Zhang YP, Liu Y, Luo XB, Isobe M, Yuan GL, Liu YQ, Hua Y, Song XY, Yang JW, Li X, Chen W, Li Y, Yan LW, Song XM, Yang QW, Duan XR. Development of the scintillator-based probe for fast-ion losses in the HL-2A tokamak. Rev Sci Instrum 2014; 85:053502. [PMID: 24880364 DOI: 10.1063/1.4872385] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A new scintillator-based lost fast-ion probe (SLIP) has been developed and operated in the HL-2A tokamak [L. W. Yan, X. R. Duan, X. T. Ding, J. Q. Dong, Q. W. Yang, Yi Liu, X. L. Zou, D. Q. Liu, W. M. Xuan, L. Y. Chen, J. Rao, X. M. Song, Y. Huang, W. C. Mao, Q. M. Wang, Q. Li, Z. Cao, B. Li, J. Y. Cao, G. J. Lei, J. H. Zhang, X. D. Li, W. Chen, J. Chen, C. H. Cui, Z. Y. Cui, Z. C. Deng, Y. B. Dong, B. B. Feng, Q. D. Gao, X. Y. Han, W. Y. Hong, M. Huang, X. Q. Ji, Z. H. Kang, D. F. Kong, T. Lan, G. S. Li, H. J. Li, Qing Li, W. Li, Y. G. Li, A. D. Liu, Z. T. Liu, C. W. Luo, X. H. Mao, Y. D. Pan, J. F. Peng, Z. B. Shi, S. D. Song, X. Y. Song, H. J. Sun, A. K. Wang, M. X. Wang, Y. Q. Wang, W. W. Xiao, Y. F. Xie, L. H. Yao, D. L. Yu, B. S. Yuan, K. J. Zhao, G. W. Zhong, J. Zhou, J. C. Yan, C. X. Yu, C. H. Pan, Y. Liu, and the HL-2A Team, Nucl. Fusion 51, 094016 (2011)] to measure the losses of neutral beam ions. The design of the probe is based on the concept of the α-particle detectors on Tokamak Fusion Test Reactor (TFTR) using scintillator plates. The probe is capable of traveling across an equatorial plane port and sweeping the aperture angle rotationally with respect to the axis of the probe shaft by two step motors, in order to optimize the radial position and the collimator angle. The energy and the pitch angle of the lost fast ions can be simultaneously measured if the two-dimensional image of scintillation light intensity due to the impact of the lost fast ions is detected. Measurements of the fast-ion losses using the probe have been performed during HL-2A neutral beam injection discharges. The clear experimental evidence of enhanced losses of beam ions during disruptions has been obtained by means of the SLIP system. A detailed description of the probe system and the first experimental results are reported.
Collapse
Affiliation(s)
- Y P Zhang
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - Yi Liu
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - X B Luo
- Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610041, China
| | - M Isobe
- National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5259, Japan
| | - G L Yuan
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - Y Q Liu
- Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610041, China
| | - Y Hua
- Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610041, China
| | - X Y Song
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - J W Yang
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - X Li
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - W Chen
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - Y Li
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - L W Yan
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - X M Song
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - Q W Yang
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - X R Duan
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| |
Collapse
|
13
|
Zhong WL, Shi ZB, Huang XL, Liu ZT, Chen W, Jiang M, Li J, Cui ZY, Song XM, Chen LY, Zou XL, Ding XT, Liu Y, Yan LW, Yang QW, Duan XR. Development of frequency modulated continuous wave reflectometer for electron density profile measurement on the HL-2A tokamak. Rev Sci Instrum 2014; 85:013507. [PMID: 24517765 DOI: 10.1063/1.4861918] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The frequency modulated continuous wave reflectometer was developed for the first time on the HL-2A tokamak. The system utilizes a voltage controlled oscillator and an active multiplier for broadband coverage and detects as heterodyne mode. Three reflectometers have been installed and operated in extraordinary mode polarization on HL-2A to measure density profiles at low field side, covering the Q-band (33-50 GHz), V-band (50-75 GHz), and W-band (75-110 GHz). For density profile reconstruction from the phase shift of the probing wave, a corrected phase unwrapping method is introduced in this article. The effectiveness of the method is demonstrated. The density profile behavior of a fast plasma event is presented and it demonstrates the capability of the reflectometer. These diagnostics will be contributed to the routine density profile measurements and the plasma physics study on HL-2A.
Collapse
Affiliation(s)
- W L Zhong
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - Z B Shi
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - X L Huang
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - Z T Liu
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - W Chen
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - M Jiang
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - J Li
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - Z Y Cui
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - X M Song
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - L Y Chen
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - X L Zou
- CEA, IRFM, F-13108 Saint-Paul-lez-Durance, France
| | - X T Ding
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - Yi Liu
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - L W Yan
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - Q W Yang
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| | - X R Duan
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, China
| |
Collapse
|
14
|
Cheng J, Dong JQ, Itoh K, Yan LW, Xu M, Zhao KJ, Hong WY, Huang ZH, Ji XQ, Zhong WL, Yu DL, Itoh SI, Nie L, Kong DF, Lan T, Liu AD, Zou XL, Yang QW, Ding XT, Duan XR, Liu Y. Dynamics of low-intermediate-high-confinement transitions in toroidal plasmas. Phys Rev Lett 2013; 110:265002. [PMID: 23848884 DOI: 10.1103/physrevlett.110.265002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Indexed: 06/02/2023]
Abstract
The dynamic features of the low-intermediate-high-(L-I-H) confinement transitions on HL-2A tokamak are presented. Here we report the discovery of two types of limit cycles (dubbed type-Y and type-J), which show opposite temporal ordering between the radial electric field and turbulence intensity. In type-Y, which appears first after an L-I transition, the turbulence grows first, followed by the localized electric field. In contrast, the electric field leads type-J. The turbulence-induced zonal flow and pressure-gradient-induced drift play essential roles in the two types of limit cycles, respectively. The condition of transition between types-Y and -J is studied in terms of the normalized radial electric field. An I-H transition is demonstrated to occur only from type-J.
Collapse
Affiliation(s)
- J Cheng
- Southwestern Institute of Physics, Chengdu 610041, People's Republic of China
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Xu M, Tynan GR, Diamond PH, Manz P, Holland C, Fedorczak N, Thakur SC, Yu JH, Zhao KJ, Dong JQ, Cheng J, Hong WY, Yan LW, Yang QW, Song XM, Huang Y, Cai LZ, Zhong WL, Shi ZB, Ding XT, Duan XR, Liu Y. Frequency-resolved nonlinear turbulent energy transfer into zonal flows in strongly heated L-mode plasmas in the HL-2A tokamak. Phys Rev Lett 2012; 108:245001. [PMID: 23004280 DOI: 10.1103/physrevlett.108.245001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Indexed: 06/01/2023]
Abstract
The absolute rate of nonlinear energy transfer among broadband turbulence, low-frequency zonal flows (ZFs) and geodesic acoustic modes (GAMs) was measured for the first time in fusion-grade plasmas using two independent methods across a range of heating powers. The results show that turbulent kinetic energy from intermediate frequencies (20-80 kHz) was transferred into ZFs and GAMs, as well as into fluctuations at higher frequencies (>80 kHz). As the heating power was increased, the energy transfer from turbulence into GAMs and the GAM amplitudes increased, peaked and then decreased, while the energy transfer into the ZFs and the ZFs themselves increased monotonically with heating power. Thus there exists a competition between ZFs and GAMs for the transfer of turbulent energy, and the transfer into ZFs becomes dominant as the heating power is increased. The poloidal-radial Reynolds stress and the mean radial electric field profiles were also measured at different heating powers and found to be consistent with the energy transfer measurement. The results suggest that ZFs play an important role in the low-to-high (L-H) plasma confinement transition.
Collapse
Affiliation(s)
- M Xu
- Center for Momentum Transport and Flow Organization, University of California at San Diego, California 92093, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Zhong WL, Shi ZB, Zou XL, Ding XT, Huang XL, Dong YB, Liu ZT, Xiao WW, Ji XQ, Cui ZY, Liu Y, Yan LW, Yang QW, Duan XR. Time-frequency analysis for microwave reflectometry data processing in the HL-2A tokamak. Rev Sci Instrum 2011; 82:103508. [PMID: 22047295 DOI: 10.1063/1.3657157] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The Choi-Williams distribution (CWD) technique is introduced as a time-frequency tool for processing data measured from the new developed homodyne and the fixed frequency reflectometry in the HL-2A tokamak. The comparison between spectrogram and CWD for the simulated signal is presented. It indicates that the CWD can greatly improve the representation of the time-frequency content of the multi-components signal. Its effectiveness is demonstrated through two applications in HL-2A, which are the extraction of beat frequencies from the frequency modulated-continuous wave reflectometry (FM-CW) and the characterizing of the fluctuations. The density profile inversed from the group delay of the FM-CW and the density fluctuations deduced from the fixed-frequency reflectometry would be more reliable and accurate by using the CWD technique.
Collapse
Affiliation(s)
- W L Zhong
- Southwestern Institute of Physics, Chengdu 610041, People's Republic of China.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Xiao WW, Zou XL, Ding XT, Yao LH, Feng BB, Song XM, Song SD, Zhou Y, Liu ZT, Yuan BS, Sun HJ, Ji XQ, Gao YD, Li YG, Yan LW, Yang QW, Liu Y, Dong JQ, Duan XR, Liu Y, Pan CH. Observation of a spontaneous particle-transport barrier in the HL-2A tokamak. Phys Rev Lett 2010; 104:215001. [PMID: 20867107 DOI: 10.1103/physrevlett.104.215001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2008] [Indexed: 05/29/2023]
Abstract
Using the profile analysis, the density perturbation transport analysis, and the Doppler reflectometry measurement, for the first time a spontaneous and steady-state particle-transport barrier has been evidenced in the Ohmic plasmas in the HL-2A tokamak with no externally applied momentum or particle input except the gas puffing. A threshold in density has been found for the observation of the barrier. The particle diffusivity is well-like, and the convection is found to be inward outside the well and outward inside the well. The formation of the barrier coincides with the transition between the trapped electron mode and the ion temperature gradient driven mode.
Collapse
Affiliation(s)
- W W Xiao
- Southwestern Institute of Physics, P.O. Box 432, Chengdu, China
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Xiao WW, Zou XL, Ding XT, Dong JQ, Yao LH, Song SD, Liu ZT, Gao YD, Feng BB, Song XM, Yang QW, Yan LW, Liu Y, Duan XR, Pan CH, Liu Y. A method of particle transport study using supersonic molecular beam injection and microwave reflectometry on HL-2A tokamak. Rev Sci Instrum 2010; 81:013506. [PMID: 20113099 DOI: 10.1063/1.3274201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A method of the particle transport study using supersonic molecular beam injection (SMBI) and microwave reflectometry is reported in this paper. Experimental results confirm that pulsed SMBI is a good perturbation source with deeper penetration and better localization than the standard gas puffing. The local density modulation is induced using the pulsed SMBI and the perturbation density is measured by the microwave reflectometry. Using Fourier transform analysis for the local density perturbation, radial profiles of the amplitude and phase of the density modulation can be obtained. The experimental results in HL-2A show that the particle injected by SMBI is located at about r/a=0.65-0.75. The position of the main particle source can be determined through three aspects: the minimum of the phase of the first harmonic of the Fourier transform of the modulated density measured by microwave reflectometry; the H(a) intensity profile and the local density increase ratio. The maximum of the amplitude of the first harmonic shifts often inward relative to the particle source location, which indicates clearly there is an inward particle pinch in this area. Good agreement has been found between the experimental results and the simulation using analytical transport model. The particle diffusivity D and the particle convection velocity V have been obtained by doing this simulation. The sensitivity in the transport coefficients of the amplitude and the phase of the density modulation has been discussed.
Collapse
Affiliation(s)
- W W Xiao
- Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041, People's Republic of China.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Liu AD, Lan T, Yu CX, Zhao HL, Yan LW, Hong WY, Dong JQ, Zhao KJ, Qian J, Cheng J, Duan XR, Liu Y. Characterizations of low-frequency zonal flow in the edge plasma of the HL-2A tokamak. Phys Rev Lett 2009; 103:095002. [PMID: 19792802 DOI: 10.1103/physrevlett.103.095002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2009] [Indexed: 05/28/2023]
Abstract
A low-frequency (<4 kHz), poloidally and toroidally symmetrical potential structure that peaks near zero frequency is observed in the edge plasma of the HL-2A tokamak. The axisymmetry structure exhibits a radial coherence length less than 1 cm. These characteristics are consistent with the theoretically predicted low-frequency zonal flows (LFZF). The radial wave-number frequency spectra of the LFZF show that the LFZF packets propagate both outwards and inwards. The geodesic acoustic mode (GAM) is found to coexist with the LFZF, and the LFZF is found to modulate the GAM and ambient turbulence with in-phase and antiphase relations, respectively, through an envelope analysis.
Collapse
Affiliation(s)
- A D Liu
- CAS Key Laboratory of Basic Plasma Physics, and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Zhao KJ, Lan T, Dong JQ, Yan LW, Hong WY, Yu CX, Liu AD, Qian J, Cheng J, Yu DL, Yang QW, Ding XT, Liu Y, Pan CH. Toroidal symmetry of the geodesic acoustic mode zonal flow in a tokamak plasma. Phys Rev Lett 2006; 96:255004. [PMID: 16907314 DOI: 10.1103/physrevlett.96.255004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2006] [Revised: 04/28/2006] [Indexed: 05/11/2023]
Abstract
The toroidal symmetry of the geodesic acoustic mode (GAM) zonal flows is identified with toroidally distributed three step Langmuir probes at the edge of the HuanLiuqi-2A (commonly referred to as HL-2A) tokamak plasmas for the first time. High coherence of both the GAM and the ambient turbulence for the toroidally displaced measurements along a magnetic field line is observed, in contrast with the high coherence of the GAM but low coherence of the ambient turbulence when the toroidally displaced measurements are not along the same field line. The radial and poloidal features of the flows are also simultaneously determined. The nonlinear three wave coupling between the high frequency turbulent fluctuations and the flows is demonstrated to be a plausible formation mechanism of the flows.
Collapse
Affiliation(s)
- K J Zhao
- Southwestern Institute of Physics, P.O. Box 432, Chengdu, China
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Muñoz N, Wahrendorf J, Bang LJ, Crespi M, Thurnham DI, Day NE, Ji ZH, Grassi A, Yan LW, Lin LG. No effect of riboflavine, retinol, and zinc on prevalence of precancerous lesions of oesophagus. Randomised double-blind intervention study in high-risk population of China. Lancet 1985; 2:111-4. [PMID: 2862315 DOI: 10.1016/s0140-6736(85)90223-5] [Citation(s) in RCA: 88] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
A randomised double-blind intervention trial was carried out in Huixian, Henan Province, People's Republic of China, to determine whether combined treatment with retinol, riboflavine, and zinc could lower the prevalence of precancerous lesions of the oesophagus. 610 subjects in the age group 35-64 were randomised to receive once a week the active treatment (15 mg [50 000 IU] retinol, 200 mg riboflavine, and 50 mg zinc) or placebo. Both at entry to the study and at the end of the treatment, 13.5 months later, the subjects were examined, with an emphasis on signs of vitamin A and riboflavine deficiences, and riboflavine, retinol, beta-carotene, and zinc levels were measured. Compliance was excellent. The final examination, on 567 (93%) subjects, included oesophagoscopy and at least two biopsies. The intervention did not affect the prevalence of oesophageal lesions: after one year, the prevalence of oesophagitis with or without atrophy or dysplasia was 45.3% in the placebo group and 48.9% in the vitamin/zinc treated group.
Collapse
|