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1.
Rev Sci Instrum ; 89(6): 063507, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29960573

RESUMEN

Analysis of fast-ion D-alpha (FIDA) data on National Spherical Torus Experiment-Upgrade (NSTX-U) shows that the cold Dα line contaminates the FIDA baseline. The scattered light is comparable to the FIDA emission. A scattering correction is required to extract the FIDA signal. Two methods that relate the scattered light contamination to the intensity of the cold Dα line are employed. One method uses laboratory measurements with a calibration lamp; the other method uses data acquired during plasma operation and singular value decomposition analysis. After correction, both the FIDA spectra and spatial profile are in better agreement with theoretical predictions.

2.
Zhonghua Xin Xue Guan Bing Za Zhi ; 46(5): 359-363, 2018 May 24.
Artículo en Chino | MEDLINE | ID: mdl-29804437

RESUMEN

Objective: To explore the relationship between coronary tortuosity and coronary microvascular disease (CMVD). Methods: Patients with typical angina symptoms and without serious coronary artery stenosis by coronary angiography were enrolled from June 2014 to December 2016, and CMVD was diagnosed by single photon emission tomography (SPECT). According to the SPECT results, patients were divided to the CMVD group and non-CMVD group. The baseline clinical characteristics, results of coronary angiography were compared between the two groups. The logistic analysis was used to analyze the relationship between coronary tortuosity and CMVD. Result: A total of 117 cases were enrolled, with 69 cases in the CMVD group and 48 cases in the non-CMVD group. No differences were found in gender distribution, age, hypertension, lipid abnormality, hyperuricemia and uses of statins between the two groups (all P>0.05). Incidence of diabetes (78.26%(54/69) vs. 35.42% (17/48) , P<0.05), hs-CRP ((4.29±2.15)mmol/L vs. (2.63±1.20)mmol/L, P<0.001), LDL-C ((2.98±0.96)mmol/L vs. (2.52±0.83)mmol/L, P=0.008) and homocysteine ((13.7±5.61)mmol/L vs. (11.5±4.38)mmol/L, P=0.025) levels were higher in the CMVD group than in the non-CMVD group. The data derived from echocardiographic examination were similar between the two groups. The Corrected TIMI frame counts were higher in the CMVD group than in non-CMVD group (LAD: 31.56±4.92 vs. 27.31±3.75, LCX: 29.47±4.18 vs. 26.62±3.19, RCA: 29.09±5.05 vs. 26.24±3.28, all P<0.001). The incidences of coronary atherosclerosis (76.81% (53/69) vs. 27.08% (13/48) , P<0.001) and coronary tortuosity ( (60.87% (42/69) vs. 33.33% (16/48) , P=0.035) were also higher in the CMVD group than in non-CMVD group. Logistic analysis found that coronary tortuosity (OR=6.111, 95%CI 2.707-13.794, P<0.001), diabetes (OR=6.565, 95%CI 2.883-14.948, P<0.001) and coronary atherosclerosis (OR=8.918, 95%CI 3.822-20.808, P<0.001) were independent risk factors of CMVD. Conclusion: Coronary tortuosity, diabetes and coronary atherosclerosis are related to CMVD in this patient cohort.


Asunto(s)
Angiografía Coronaria , Enfermedad de la Arteria Coronaria , Enfermedad de la Arteria Coronaria/fisiopatología , Estenosis Coronaria , Ecocardiografía , Humanos , Tomografía Computarizada de Emisión de Fotón Único
3.
Rev Sci Instrum ; 87(11): 11D803, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27910528

RESUMEN

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.

4.
Cell Death Differ ; 23(5): 787-800, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26494466

RESUMEN

Testicular phagocytosis by Sertoli cells (SCs) plays an essential role in the efficient clearance of apoptotic spermatogenic cells under both physiological and pathological conditions. However, the molecular mechanism underlying this unique process is poorly understood. Herein, we report for the first time that α-taxilin protein (TXLNA), a binding partner of the syntaxin family that functions as a central player in the intracellular vesicle traffic, was dominantly expressed in SCs. Induction of apoptosis in murine meiotic spermatocytes and haploid spermatids by busulfan treatment stimulated a significant increase of TXLNA in SCs at day (d) 14 and d 24 after busulfan treatment, respectively. Consistently, TXLNA expression was steadily upregulated when SCs were co-cultured with apoptotic germ cells (GCs). Moreover, using siRNA treatment, we found that ablation of endogenous TXLNA significantly impaired the phagocytotic capacity of SCs and thereby resulted in defective spermiogenesis and reduced fertility during the late recovery after testicular heat stress. Mechanistically, upregulation of TXLNA expression by apoptotic GCs was associated with the stabilization of ATP-binding cassette transporter 1 (ABCA1), a transporter-mediated lipid efflux from SCs and influencing male fertility. TXLNA acted as an upstream suppressor of ABCA1 ubiquitination and thus promoted ABCA1 stability and accumulation following GC apoptosis. We further provide in vitro evidence that epidermal growth factor receptor (EGFR)-mediated phosphorylation regulated ABCA1 ubiquitination and was enhanced by TXLNA deficiency during testicular phagocytosis. Taken together, the TXLNA/ABCA1 cascade may serve as an important feedback mechanism to modulate the magnitude of subsequent phagocytotic process of SCs in response to testicular injury.


Asunto(s)
Transportador 1 de Casete de Unión a ATP/metabolismo , Interleucinas/metabolismo , Fagocitos/metabolismo , Fagocitosis , Células de Sertoli/citología , Células de Sertoli/metabolismo , Células 3T3 , Animales , Línea Celular , Femenino , Células HeLa , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Unión Proteica , Proteínas de Transporte Vesicular
5.
Phys Rev Lett ; 107(1): 015001, 2011 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-21797547

RESUMEN

A stability analysis for the resistive wall mode is studied in the presence of trapped energetic particles (EPs). When the EPs' beta exceeds a critical value, a fishbonelike bursting mode (FLM) with an external kink eigenstructure can exist. This offers the first analytic interpretation of the experimental observations [Phys. Rev. Lett. 103, 045001 (2009)]. The mode-particle resonances for the FLM and the q=1 fishbone occur in different regimes of the precession frequency of EPs. In certain ranges of the plasma rotation speed and the EPs' beta, a mode conversion can occur between the resistive wall mode and FLM.

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