Doppler coherence imaging of scrape-off-layer impurity flows in the HL-2A tokamak.

A new Doppler coherence imaging spectroscopy interferometer has been developed on the HL-2A tokamak for the scrape-off-layer impurity flow measurement. Its spatial resolution is estimated to be up to ∼0.8 mm in the horizontal direction and ∼9 mm in the vertical direction, with a field of view of ∼34°. Its typical temporal resolution is about 1 ms. This salient feature allows for time-resolved 2D measurements in short-time phenomena on HL-2A, such as edge localized modes. Group delay and interference fringe pattern were calibrated with a dedicated calibration system. The robustness of group delay calibration and the feasibility of the extrapolation model for fringe pattern calibration are demonstrated. In this paper, we report the details of the optical instruments, calibration, and the initial experimental results of this Doppler coherence imaging spectroscopy interferometer.

Experimental study of perturbative particle transport in the HL-2A tokamak.

Perturbative particle transport experiment has been performed in the HL-2A tokamak by using supersonic molecular beam injection (SMBI) as an external particle source. The spatiotemporal evolution of edge density perturbation is traced and the particle source and the flux-gradient relation are obtained experimentally. The flux-gradient relation is found to be far from the diffusive model and three different transport processes are revealed, including pinch-dominant process, diffusion-pinch process and intermittent decays.

[Application of bronchoalveolar lavage fluid in patients with pulmonary complications after allogeneic hematopoietic stem cell transplantation].

Objective: To evaluate the diagnostic value of bronchoalveolar lavage (BAL) for pulmonary complications in patients after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and its safety. Methods: Patients with pulmonary complications after allo-HSCT underwent BAL. Microbiological smears, culture, PCR of CMV-DNA, EBV-DNA and TB-DNA, macro genomes new generation sequencing (mNGS) techniques were performed to detect pathogens in BAL fluid (BALF) . Results: A total of 73 allo-HSCT patients with 86 times of pulmonary complications enrolled this prospective study. They underwent 132 times of BAL procedures. The clinical diagnoses of 88.4% cases were made based on BALF analysis. Of them, 67 cases (77.9%) had infectious pulmonary complications, including 29 cases (33.7%) of fungal infection, 18 cases (20.9%) of mixed infection, 11 cases (12.8%) of viral infection and 9 cases (10.5%) of bacterial infection. The other 9 cases (10.5%) of non-infectious pulmonary complications included 8 cases (9.3%) of idiopathic pneumonia syndrome (IPS) and 1 case (1.2%) of pulmonary infiltration of lymphoma. The diagnoses of the remaining 10 cases (11.6%) were not determined. The platelet counts of 33 patients were less than 50×10(9)/L before BAL. None of them developed severe bleeding complications during or after BAL. Transient fever occurred in 10 patients after BAL. Blood cultures showed staphylococcal bacteremia in them and anti-infection therapies were effective. No life-threatening complications occurred in all of the patients during or after BAL. Conclusion: BALF analysis was informative for the diagnosis of pulmonary complication and safe for patients with pulmonary complications after allo-HSCT.

Initial beam emission spectroscopy diagnostic system on HL-2A tokamak.

A beam emission spectroscopy system is being developed and deployed on the HL-2A tokamak to measure local low wavenumber (k ⊥ ρ i < 1) density fluctuations by measuring the Doppler-shifted emission from a 50 kV deuterium heating neutral beam. High spatial resolution (Δr ≤ 1 cm, Δz ≤ 1.5 cm) measurements are achieved with customized in-vacuum optics. High frequency, high-gain preamplifiers sample the light intensity at a Nyquist frequency of 1 MHz and achieve a high S/N ratio via high optical throughput, low-noise preamplifiers, and high quantum efficiency photodiodes. A first set of 16 detector channels [configured in an 8 (radial) × 2 (poloidal) array] has been installed and tested at HL-2A, covering the radial range r/a = 0.8-1.1. The frequency and wavenumber spectra have been measured under different plasma conditions. Initial measurements have demonstrated the capability of measuring edge plasma density fluctuation spectra and the poloidal flow velocity fields with a high S/N ratio.

Uptake and transformation of steroid estrogens as emerging contaminants influence plant development.

Steroid estrogens are emerging contaminants of concern due to their devastating effects on reproduction and development in animals and humans at very low concentrations. The increasing steroid estrogen in the environment all over the world contrasts very few studies for potential impacts on plant development as a result of estrogen uptake. This study evaluated the uptake, transformation and effects of estradiol (17ß-E2) and ethinyl estradiol (EE2) (0.1-1000 µg L-1) on lettuce. Uptake increased in leaves and roots in a dose-dependent manner, and roots were the major organ in which most of the estrogen was deposited. The transformation of estrogens to major metabolite and their further reverse biotransformation in lettuce tissue was identified. At low concentrations (0.1 and 50 µg L-1) estrogens resulted in enhanced photosynthetic pigments, root growth and shoot biomass. Application of higher concentrations of estrogens (10 mg L-1) significantly reduced total root growth and development. This was accompanied by increased levels of hydrogen peroxide (H2O2), and malondialdehyde (MDA), and activities of antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX). Taken together, these findings suggest that at low concentrations estrogens may biostimulate growth and primary metabolism of lettuce, while at elevated levels they have adverse effects.

[Treatment of 30 elderly patients with advanced myeloid neoplasm by allogeneic hematopoietic stem cell transplantation].

Objective: To evaluate the efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for elderly patients with advanced myeloid neoplasm. Methods: From September 2014 to September 2017, 30 consecutive hospitalized 50-plus-year-old myeloid neoplasm patients were retrospectively analyzed. At the time of transplantation, 6 patients reached complete remission and the others remained no remission after treatment. The donors were identical sibling (12), matched unrelated (6) and haploidentical family member (12), respectively. 18 patients received RIC while 12 patients received MAC conditioning regiments consisted of Busulfan, cytarabine, fludarabine or clarithromycin±TBI, respectively. Results: Five patients died early in the conditioning stage, 24 patients successfully engrafted. The median time of neutrophil engraftment was 14(10-18) d, whereas platelet engraftment was 15(10-19) d. Six cases (25%) experienced aGVHD grades Ⅱ, 8 cases (32%) cGVHD, including moderate to severe cGVHD in 2 cases (8%). Seven, 7 and 5 cases developed CMV viremia, pneumonia and herpeszoster, respectively after transplantation, but no patients died of infections. The median follow-up time of the patients was 7(0.5-38) months. Twenty-one patients were still alive. The estimated 2 years OS and LFS were 62.5% (95% CI 39.2%-85.8%) and 59.2% (95% CI 26.9%-91.5%), respectively. Univariate analysis showed that HCT-CI was the only factor influencing OS. Conclusion: Allogeneic hematopoietic stem cell transplantation could improve the survival of elderly patients with myeloid neoplasm.

[Effects of exposure to ambient particulate matter and polycyclic aromatic hydrocarbons on oxidative stress biomarkers in the patients with chronic obstructive pulmonary disease].

OBJECTIVE: To investigate the effects of exposure to ambient particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs) on systemic oxidative stress biomarkers in chronic obstructive pulmonary disease (COPD) patients. METHODS: A panel of forty-five diagnosed and stable COPD patients, whose residences were within 5 kilometers from Peking University Health Science Center (PKUHSC), were recruited and followed up twice between November 2014 and May 2015. The lung function index percentage of forced expiratory volume in 1 second (FEV1) to predicted value (FEV1%pred), was measured to reflect the severity of COPD patients. The systemic oxidative stress biomarkers malondialdehyde (MDA) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in their urine samples were measured using high performance liquid chromatography (HPLC) and enzyme-linked immunosorbent assay (ELISA), respectively. Concentrations of ambient air pollutants and levels of meteorological factors were measured continuously through the air pollution-monitoring station located in PKUHSC. PM2.5 samples, which were used for measuring the concentrations of PAHs, were collected by PM2.5 high volume air sampler. We constructed linear mixed-effects models, including single-pollutant model, 2-pollutant models and stratification analysis, to estimate the effects of air pollutants on urinary MDA and 8-OHdG after adjusting for confounding factors. RESULTS: In our COPD-patient panel, the associations between ultrafine particles (UFP) and PAHs and urinary MDA were statistically significant at lag2 (P<0.05). For an interquartile range (IQR) increase in UFP and PAHs, respective increases of 28% (95%CI: 4%-57%) and 36% (95%CI: 4%-77%) in urinary MDA were observed, and the effects became stronger after adjusting for the concentration of black carbon (BC). The COPD patients were divided into 2 groups stratified by FEV1%pred. Most air pollutants had stronger effects of systemic oxidative stress in the COPD patients of FEV1%pred≥50%. In this group, we observed that an IQR increase in UFP was associated with a 98% (95%CI: 38%-186%) increase in urinary MDA, and an IQR increase in BC, UFP and PAHs were associated with respective increases of 87% (95%CI: 32%-166%), 69% (95%CI: 24%-130%) and 156% (95%CI: 66%-294%) in urinary 8-OHdG. We didn't find significant associations between fine particulate matter (PM2.5) and urinary oxidative stress biomarkers. CONCLUSION: Our results suggested that exposure to air pollutants, especially UFP and PAHs, was responsible for exacerbation of systemic oxidative stress in COPD patients. Most air pollutants had stronger effects of systemic oxidative stress in mild to moderate COPD patients.

Facile preparation of S-doped magnetite hollow spheres for highly efficient sorption of uranium(vi).

Magnetite sorbents (MS) have been widely employed for water purification; however, adsorption capacity loss frequently occurs during the formation of magnetite sorbents. In this study, we report the preparation of S-doped magnetite hollow spheres (S-doped MHS) used for the removal of UO22+ with a large adsorption capacity of 450.0 mg U per g, higher than that of pure Fe3O4. Transmission electron microscopy (TEM), X-ray diffraction (XRD) and a vibrating sample magnetometer (VSM) were used to determine the effectiveness of the synthesis of S-doped MHS. The S-doped MHS was investigated for the adsorption of uranium(vi) from an aqueous solution. In addition, the adsorption process fits the Freundlich isotherm model and pseudo-second-order rate equation perfectly. The affinity and selectivity of S-doped MHS for uranium(vi) is significantly high. S-doped MHS can be easily separated using an external magnetic field. Moreover, S-doped MHS can be used for the adsorption of other heavy metal ions, which indicates their promising potential applications as adsorbents in aqueous solutions.

The supersonic molecular beam injector as a reliable tool for plasma fueling and physics experiment on HL-2A.

On HL-2A tokamak, supersonic molecular beam injection (SMBI) has been developed as a routine refueling method. The key components of the system are an electromagnetic valve and a conic nozzle. The valve and conic nozzle are assembled to compose the simplified Laval nozzle for generating the pulsed beam. The appurtenance of the system includes the cooling system serving the cooled SMBI generation and the in situ calibration component for quantitative injection. Compared with the conventional gas puffing, the SMBI features prompt response and larger fueling flux. These merits devote the SMBI a good fueling method, an excellent plasma density feedback control tool, and an edge localized mode mitigation resource.

Synchronization of Geodesic Acoustic Modes and Magnetic Fluctuations in Toroidal Plasmas.

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.

Observation of Double Impurity Critical Gradients for Electromagnetic Turbulence Excitation in Tokamak Plasmas.

The impact of impurity ions on a pedestal has been investigated in the HL-2A Tokamak, at the Southwestern Institute of Physics, Chengdu, China. Experimental results have clearly shown that during the H-mode phase, an electromagnetic turbulence was excited in the edge plasma region, where the impurity ions exhibited a peaked profile. It has been found that double impurity critical gradients are responsible for triggering the turbulence. Strong stiffness of the impurity profile has been observed during cyclic transitions between the I-phase and H-mode regime. The results suggest that the underlying physics of the self-regulated edge impurity profile offers the possibility for an active control of the pedestal dynamics via pedestal turbulence.

Development of the radial neutron camera system for the HL-2A tokamak.

A new radial neutron camera system has been developed and operated recently in the HL-2A tokamak to measure the spatial and time resolved 2.5 MeV D-D fusion neutron, enhancing the understanding of the energetic-ion physics. The camera mainly consists of a multichannel collimator, liquid-scintillation detectors, shielding systems, and a data acquisition system. Measurements of the D-D fusion neutrons using the camera have been successfully performed during the 2015 HL-2A experiment campaign. The measurements show that the distribution of the fusion neutrons in the HL-2A plasma has a peaked profile, suggesting that the neutral beam injection beam ions in the plasma have a peaked distribution. It also suggests that the neutrons are primarily produced from beam-target reactions in the plasma core region. The measurement results from the neutron camera are well consistent with the results of both a standard (235)U fission chamber and NUBEAM neutron calculations. In this paper, the new radial neutron camera system on HL-2A and the first experimental results are described.

[Airway oxidative stress and inflammation markers in chronic obstructive pulmonary diseases(COPD) patients are linked with exposure to traffic-related air pollution: a panel study].

OBJECTIVE: To investigate the effects of short-term exposure to traffic-related air pollution on airway oxidative stress and inflammation in chronic obstructive pulmonary diseases (COPD) patients. METHODS: A panel of forty-five diagnosed COPD patients were recruited and followed with repeated measurements of biomarkers reflecting airway oxidative stress and inflammation in exhaled breath condensate (EBC), including nitrate and nitrite, 8-isoprostane, interleukin-8 and acidity of EBC (pH), between 5(th) September in 2014 and 26(th) May in 2015. The associations between air pollution and biomarkers were analyzed with mixed-effects models, controlling for confounding covariates. RESULTS: The concentration of PM2.5, black carbon, NO2 and number concentration of particles with diameter less than 100 nm (PNC100), and particles in size ranges between 100 nm to 200 nm (PNC100-200) during the first follow-up were (156.5±117.7), (10.7±0.7), (165.9±66.0)µg/m(3) and 397 521±96 712, 79 421±44 090 per cubic meter, respectively; the concentration were (67.9±29.6), (3.4±1.3), (126.1±10.9) µg/m(3) and (295 682±39 430), (24 693±12 369) per cubic meter, respectively during the second follow-up. The differences were of significance, with t value being 3.10, 4.42, 2.61, 4.02, 5.12, respectively and P value being 0.005,<0.001, 0.016, <0.001 and <0.001, respectively. In our COPD-patient panel, per interquartile range (IQR) increase in PNC100-200, we observed an increase of 65% (95% CI: 8%-152%) in nitrate and nitrite in EBC reflecting airway oxidative stress. For an IQR increase in PM2.5, black carbon and PNC100-200, respective increases of 0.17 ng/ml (95% CI: 0.02-0.33), 0.12 ng/ml (95% CI: 0.01-0.24) and 0.13 ng/ml (95% CI:0.02-0.24) in interleukin-8 in EBC reflecting airway inflammation were also observed. An IQR increase in ozone was also associated with a 0.24 (95%CI: 0.05-0.42) decrease in pH of EBC reflecting increased airway inflammation. No significant association observed between air pollution and 8-isoprostane in EBC in COPD patients. CONCLUSION: Our results suggested that short-term exposure to traffic-related air pollution was responsible for exacerbation of airway oxidative stress and inflammation in COPD patients.

HAMI 3379, a CysLT2R antagonist, dose- and time-dependently attenuates brain injury and inhibits microglial inflammation after focal cerebral ischemia in rats.

Cysteinyl leukotrienes (CysLTs) induce inflammatory responses by activating their receptors, CysLT1R and CysLT2R. We have reported that CysLT2R is involved in neuronal injury, astrocytosis, and microgliosis, and that intracerebroventricular (i.c.v.) injection of the selective CysLT2R antagonist HAMI 3379 protects against acute brain injury after focal cerebral ischemia in rats. In the present study, we clarified features of the protective effect of intraperitoneally-injected HAMI 3379 in rats. We found that HAMI 3379 attenuated the acute brain injury 24 h after middle cerebral artery occlusion (MCAO) with effective doses of 0.1-0.4 mg/kg and a therapeutic window of ∼1h. It attenuated the neurological deficits, and reduced infarct volume, brain edema, and neuronal loss and degeneration 24 and 72h after MCAO. RNA interference with i.c.v. injection of CysLT2R short hairpin RNA (shRNA) attenuated the acute injury as well. Also, HAMI 3379 inhibited release of the cytokines IL-1ß, interferon-γ (IFN-γ), and tumor necrosis factor-α (TNF-α) into the serum and cerebrospinal fluid 24h after MCAO. Moreover, HAMI 3379 ameliorated the microglial activation and neutrophil accumulation in the ischemic regions, but did not affect astrocyte proliferation 72h after MCAO. In comparison, the CysLT1R antagonist pranlukast did not affect microglial activation and IFN-γ release, but inhibited astrocyte proliferation and reduced serum IL-4. Thus, we conclude that HAMI 3379 has a protective effect on acute and subacute ischemic brain injury, and attenuates microglia-related inflammation. CysLT2R antagonist(s) alone or in combination with CysLT1R antagonists may be a novel class of therapeutic agents in the treatment of ischemic stroke.

Serum CYFRA21-1 as an effective tumor biomarker for patients with nasopharyngeal carcinoma.

UNLABELLED: We investigated if the serum cytokeratin 19 fragment 21.1 (CYFRA21-1) level was elevated in nasopharyngeal carcinoma (NPC) and can function as a biomarker for detection and monitoring of NPC. Three hundred and one study subjects were divided into two groups: the NPC group (n=126) and healthy control group (n=175). Serum CYFRA21-1 levels were measured before and after treatment using a chemiluminescent immunoassay, and its association with tumor stage and the clinical objective responses were analyzed. Receiver operating characteristic (ROC) curve analysis was performed to discriminate patients with NPC from the healthy controls. The pretreatment serum CYFRA21-1 level was significantly elevated in patients with NPC compared with the healthy controls (5.07±1.98 ng/ml vs 2.36±1.21 ng/ml, p<0.001), and it declined significantly after the entire treatment (2.14±0.72 ng/ml, p<0.001). The serum CYFRA21-1 level of patients with a classification of T3-4 was significantly higher than that of those with class T1-2 (5.64±2.23 ng/ml vs 4.62±1.64 ng/ml, p=0.006), and that of patients with clinical stage III-IV was higher than clinical stage I-II (5.31±2.02 vs 4.04±1.37 ng/ml, p=0.003). The AUC, sensitivity and specificity of elevated serum CYFRA21-1 in patients with NPC was 0.91, 0.83 and 0.89 respectively. In conclusion, the serum CYFRA21-1 level could be a reliable and effective biomarker for the detection and monitoring of NPC tumor progression. KEYWORDS: nasopharyngeal carcinoma, CYFRA21-1, tumor biomarker, receiver operating characteristic curve.

Development of the scintillator-based probe for fast-ion losses in the HL-2A tokamak.

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.

Development of frequency modulated continuous wave reflectometer for electron density profile measurement on the HL-2A tokamak.

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.

Effects of alfalfa meal on the intestinal microbial diversity and immunity of growing ducks.

This study was conducted to investigate the effects of alfalfa meal diets on the intestinal microbial diversity and immunity of growing egg-type ducks. A total of 128 healthy 7-week-old female egg-type Shaoxing ducks were selected and randomly assigned into four dietary treatments: 0%, 3%, 6% and 9% alfalfa meal for 8 weeks. Each treatment consisted of four replicates of eight ducks each. Polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) was used to characterize the microbiota. The results showed that the DGGE fingerprints of the V6-V8 fragments of the 16S rRNA from the caeca and faeces of ducks fed 3%, 6% and 9% alfalfa meal had significantly higher microbiota species richness than those fed 0% alfalfa meal (p < 0.05). The Shannon-Weiner index of the microbiota from the caeca and faeces of ducks fed 3%, 6% and 9% alfalfa meal was significantly higher than those fed 0% alfalfa meal (p < 0.05). Molecular analysis of the caecal and faecal DNA extracts showed that the alfalfa meal diet promotes the intestinal microbial diversity, as indicated by their higher species richness and Shannon-Weiner index. However, the groups did not significantly differ in terms of average daily gain, feed intake and gain-to-feed ratio (p > 0.05), and the 3-9% alfalfa meal did not affect the growth performance of the growing egg-type ducks. The proliferation of T and B lymphocytes was significantly greater (p < 0.05) in the groups supplemented with 3%, 6% and 9% of alfalfa meal than the unsupplemented control group, and alfalfa meal promoted the lymphocytes proliferation of the growing egg-type ducks. Dietary alfalfa meal supplementation increases intestinal microbial community diversity and improves of the immune response growing egg-type ducks.