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Cerebral ischemia is divided into local cerebral ischemia and diffuse cerebral ischemia. The etiology of localized cerebral ischemia includes middle cerebral artery embolism; Stenosis, occlusion, or thrombosis of extracranial internal carotid artery or vertebral artery; and Cerebral artery spasm. The causes of diffuse cerebral ischemia include cardiac arrest, hypotension, anemia, and hypoglycemia. However, the underlying mechanism is still unclear. In this study, we demonstrated that activator of transcription 3 (ATF3) is a hubgene in IS by bioinformatics analysis. The expression of ATF3 was increased in PC12 cells with oxygen-glucose deprivation/reoxygenation (OGD/R) treatment. ATF3 deficiency inhibited cell viability and induced cell apoptosis, whereas ATF3 overexpression showed the opposite role in cell viability and cell apoptosis. Moreover, Carvedilol as a compound targeting ATF3 also facilitated cell viability and reduced cell apoptosis. ATF3 deficiency retarded the increase in cell viability and inhibition of cell apoptosis in OGD/R-PC12 cells with Carvedilol treatment. Additionally, the decreased Bax and Cleaved Caspase-3 was released in in OGD/R-PC12 cells with Carvedilol and siATF3 treatment, while Bcl-2 expression was inhibited in in OGD/R-PC12 cells with Carvedilol and siATF3 treatment. In conclusion, Carvedilol may be a key compound targeting ATF3 in OGD/R-PC12 cells.

An arc discharge in water can generate extremely high voltage, which has great potential to be used in DC fault protection. The voltage characteristic is closely related to the arc behaviors. However, due to the complexity of the gas–liquid mixed environment, the arc shape is difficult to observe directly. In this letter, an observation device is specially designed and underwater arc motion with millisecond-scale duration is clearly photographed. The corresponding relationship between the arc behaviors and the varied voltage is revealed. Additionally, the random behaviors of underwater arc are controlled stably by applying an external transverse magnetic field. The enhanced cooling mechanism and the directional arc motion characteristics are discussed. We demonstrate that fast elongation of the arc column and continuous heat exchange between phase surfaces are the keys to realizing a rapid increase of underwater arc voltage.

Arc plasmas have been extensively studied, experimentally and by means of modeling, due to their wide range of applications. In this article, a calibration-free Boltzmann plot method was applied to measure the species composition and pressure in the arc plasmas based on the assumption of local thermodynamic equilibrium and only single ionization of atoms. Experiments were performed on the argon free-burning arcs at two different pressures. Firstly, several Ar I and Ar II spectral lines were utilized to draw the Boltzmann plot. Then, the plasma temperatures were obtained by three different methods, the Boltzmann plot method, two-line Saha–Boltzmann plot method, and the Fowler–Milne method. The species concentration was calculated using the intercepts with ordinate in the Boltzmann plot. Combined with the electron number density determined from the Stark broadening of Ar I 696.54 nm, arc pressures are calculated based on the equation of state. The measured species concentration and pressures are in good agreement with the theoretical results, indicating that the used method is reliable for further arc plasma applications.

Laser Thomson scattering and Rayleigh scattering methods were applied to investigate the dynamics of laser-induced plasmas in atmospheric air. Laser-induced plasma was generated by a 1064 nm, 200 mJ Nd: YAG laser. Another nanosecond Nd: YAG laser (532 nm, 50 mJ) was used as the probe laser. The temporally and spatially resolved electron number density and temperature distributions of the laser-induced plasma were determined from the Thomson scattering spectra. From 1 μs to 21 μs after plasma generation, the electron number density around the centre of the plasma decreased from 4.96 × 1023m‐3 to approximately 1.1 × 1021m‐3, while the electron temperature dropped from approximately 51,500 K to 6900 K. The plasma images and the measured distribution of the electron number density and temperature indicated the formation of a toroidal structure approximately 18 μs after plasma generation. The Rayleigh scattering results show that the Taylor-Sedov model cannot well describe the early evolution of the shockwave in radial directions.

Aim: In this study, we investigated the effect of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio on restenosis status in patients undergoing carotid angioplasty stenting (CAS). Methodology & results: Clinical imageology and receiver operating characteristic analysis were utilized to study the prognostic significance of NLRs/platelet-to-lymphocyte ratios and their correlation with survival. NLR of restenosis (+) patients was evidently increased after the CAS procedures, while the NLR of restenosis (-) patients before the CAS procedures being the lowest. Area under the curve of pre-CAS NLR or/and post-CAS NLR were all evidently higher than 50%. Also, restenosis incidence was the highest in patients with both high pre-CAS and high post-CAS values. Conclusion: Therefore, NLR can be utilized as an independent prognostic indicator to predict the incidence of restenosis after CAS procedures.

The pre-charged capacitor method, used in the active current injection circuit breaker in DC system, is an effective approach to realize the current injection. However, in practical applications, the performances of post-arc among different opening speed are still unknown, which have been an obstacle that blocks the design of MV DCCB. To solve this problem, high resolution measuring equipment was used to investigate the performances of vacuum circuit breaker in post-arc period. The experimental results show that the peak value of the post-arc current can be up to 6A and the post-arc current decays to zero within 10μs after current-zero. Besides, with the increase of opening speed, the fluctuation of post-arc charge increases continuously, while the average remains basically unchanged.

Carbon dioxide (CO2) is a promising alternative to sulfur hexafluoride for high-voltage circuit breaker applications. It is important to have a detailed understanding of CO2 arc properties. In this paper, radial temperature distribution of the free burning direct current arc in pure CO2 was investigated. Optical emission spectrometry was applied under different pressures (0.5 atm, 1 atm, and 1.5 atm) and at different axial positions (1 mm, 2 mm, 3 mm above the cathode). Assuming local thermodynamic equilibrium, the Fowler–Milne method was adopted for O I 715.67 nm and O I 777.19 nm in the periphery of the arc, and the single-line method was adopted for C II 657.81 nm near the center of the arc. Radial temperature profiles obtained by these two methods were combined at the position where normal temperature was assigned. The results indicate that near the center of the arc, higher pressure would lead to lower temperature; as the distance from the cathode to the position measured increases, the maximum temperature in the arc center would decrease. In addition, the temperature would decrease more sharply toward the periphery if the central temperature of the arc is higher.