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Ischemic stroke (IS) is a central nervous system neurological disorder ascribed to an acute focal trauma, with high mortality and disability, leading to a heavy burden on family and society. Autophagy is a self-digesting process by which damaged organelles and useless proteins are recycled to maintain cellular homeostasis, and plays a pivotal role in the process of IS. Non-coding RNAs (ncRNAs), mainly contains microRNA, long non-coding RNA and circular RNA, have been extensively investigated on regulation of autophagy in human diseases. Recent studies have implied that ncRNAs-regulating autophagy participates in pathophysiological process of IS, including cell apoptosis, inflammation, oxidative stress, blood-brain barrier damage and glial activation, which indicates that regulating autophagy by ncRNAs may be beneficial for IS treatment. This review summarizes the role of autophagy in IS, as well as focuses on the role of ncRNAs-mediated autophagy in IS, for the development of potential therapeutic strategies in this disease.

Water management is a critical issue to be solved efficiently for an air-breathing direct methanol fuel cell (DMFC). The cell performance decreases sharply once the water flooding occurs. In this paper, a novel strategy of water removal is proposed by incorporating a functional self-made expanded metal mesh, which can be used as the cathode flow field in a DMFC. Experiments show that water can be directly discharged in the form of water film or water line from the water outlet to the bottom underneath the expanded mesh. The water management can be further improved by using absorbent cottons, suitable feed rates and an upright texture direction of the metal mesh. Results also show that only a few mesh openings are blocked by water when the tested device tilts from 60° to 120°. In a real DMFC, the expanded mesh displays an excellent ability in water removal compared to the traditional perforated flow fields. The cathode water only gathers at the bottom and covers very few mesh openings. This new method helps efficiently avoid the issue of water flooding at the cathode using the expanded mesh.

Correlation coefficient is usually used to measure the correlation degree between two time signals. However, its performance will drop or even fail if the signals are noised. Based on the time-frequency phase spectrum (TFPS) provided by normal time-frequency transform (NTFT), similarity coefficient is proposed to measure the similarity between two non-narrow-band time signals, even if the signals are noised. The basic idea of the similarity coefficient is to translate the interest part of signal f1(t)'s TFPS along the time axis to couple with signal f2(t)'s TFPS. Such coupling would generate a maximum if f1(t)and f2(t) are really similar to each other in time-frequency structure. The maximum, if normalized, is called similarity coefficient. The location of the maximum indicates the time delay between f1(t) and f2(t). Numerical results show that the similarity coefficient is better than the correlation coefficient in measuring the correlation degree between two noised signals. Precision and accuracy of the time delay estimation (TDE) based on the similarity analysis are much better than those based on cross-correlation (CC) method and generalized CC (GCC) method under low SNR., Comment: 14 pages and 8 figures

Surface-pattern engineering, as a key strategy to fabricate high-performance Nafion membranes for fuel cells, plays an important role in surface functionalization of the membrane, optimization of the three-phase boundary, water management, proton transport, etc. Considerable efforts have been dedicated to developing advanced-patterned Nafion membranes with single-scale (nanoscale or microscale) and multiscale-patterned structures which are believed to improve the performance of membrane electrode assemblies (MEAs) for fuel cells. In this review, the recent progress in surface-patterned Nafion membranes (SPNMs) equipped with single-scale-patterned structures (including nanostructured and microstructured Nafion membranes) is firstly highlighted. The structural features and construction methods of SPNMs are discussed in detail. The effects of single-scale SPNMs on the construction and performance of fuel cells are also analyzed. Followed is an overview of the recent advances in fabricating multiscale SPNMs based on different strategies with a specific introduction on the membrane related effects on fuel cells. Finally, the future development direction and certain perspectives on the current issues of SPNMs are presented.

Management of the produced carbon dioxide (CO2) is important to improve the performance of a liquid-feed direct methanol fuel cell (DMFC). This work investigates the CO2 bubble behaviors and the two-phase flow characteristics, using a single sinusoidal corrugated channel as the anode flow field. The magnitude and gradient of the fluid velocity in this channel is higher than the traditional straight pattern, as proven by tracking CO2 bubbles. The use of high magnitude and gradient of velocity enhances CO2 emission and fuel delivery, as well as increases the pressure drop. The vortices in the disturbance structure of the corrugated channel help uniformly deliver the reactants and separate bubbles away from the channel wall. Using excessive values of amplitude A and angular frequency W in the corrugated channel causes serious bubble deformation and extra energy consumption. The effect of disturbance structure is negligible with small values of these two parameters. The cell with a corrugated channel shows a higher performance at different feed rates and concentrations of the methanol fuel. The optimal value of A and W are respectively 0.1and 5. The visualization tests demonstrate that the appearance of CO2 bubbles in the corrugated channel is consistent with the simulation results.

Determined direct evaporative cooling with Lanzhou subway summer air-conditioning outdoor calculated dry bulb and wet bulb temperature of 28.2 °C and 18.1 °C respectively. In turn, by simulating the entry conditions, tested the stainless steel packing, the aluminum foil packing, the plant fiber packing, the glass fiber packing and polymer filler packing 5different packing types at the different thickness, different face velocity and different combination of water spray density of direct evaporative cooling efficiency and resistance, ultimately determined to use the stainless steel packing. Tested the stainless steel packing small prototype, preliminarily determine the best thickness is 450 mm; the best face velocity is 3 m/s; the

Classical correlation reflects linear relation between two signals completely in frequency domain, while wavelet correlation, introducing scale parameter to the classical one, is studied to realize similarity degree analysis both in time domain and frequency domain. So the latter is superior to analyzing correlation between two non-stationary geodetic signals. Wavelet correlation can detect similarity degree at different frequencies and delays and give expression to delay information while the correlation obtains maximum at a certain frequency. In order to determine the scales in which feature information lies, wavelet spectrum, combining wavelet transform and Fourier spectrum analysis, is used to explore feature information at different scales. It can be seen cycle information— cycles of a month, a season, half of a year, and a year—hidden in signals from stations in Shandong through wavelet spectrum analysi. Then linear relation between signals from two stations at three directions, North, East and Up, is analyzed by wavelet correlation respectively.