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Highlights: [•] CAS improves cognitive function in non-diabetic patients. [•] CAS causes a decline in S-100B level in non-diabetic patient. [•] The improvement of cognitive function is correlated with the decrement of S-100B. [ABSTRACT FROM AUTHOR]

Abstract: We present a new Aleksandrov–Bakelman–Pucci maximum principle for -Laplacian operator. Our proof is based on the solution of an obstacle problem. [Copyright &y& Elsevier]

Abstract: We consider the minimum problem for the functional in three dimensional space, where is a constant. We will establish a Liouville type theorem for this variational problem: if is a nonnegative and nonzero global minimizer, then for some point and some unit vector . [Copyright &y& Elsevier]

Abstract: We present a more general form of the mountain pass lemma. It asserts that a functional which satisfies the Palais–Smale condition admits a critical value when the connectedness of certain level sets changes. We also give an improved form of a theorem given in [A. Bahri, H. Berestycki, A perturbation method in critical point theory and applications, Trans. Amer. Math. Soc. 267 (1) (1981) 1–32], which characterizes the existence of the critical value by means of contractibility properties of the level sets. [Copyright &y& Elsevier]

In this paper, using the existence and comparison conclusion for the time-periodic quasimonotone nondecreasing systems given by Pao C.V. and iterative method, we investigate the time-periodic Lotka–Volterra cooperating model and present some existence, uniqueness and nonexistence results. We also use similar methods to treat the corresponding stationary system to give parallel results. [Copyright &y& Elsevier]

• Elucidated m6A RNA modification in cerebral I/R injury. • Downregulated FTO expression leads to increased m6A RNA modification. • FTO overexpression reverses increased total m6A RNA modification. • It exerts a protective effect against cerebral I/R injury. This study aimed to elucidate the mechanism for alteration of m6A RNA modification in cerebral ischemia/reperfusion(I/R) injury and identify novel therapeutic targets. A rat cerebral I/R injury model was established by middle cerebral artery occlusion (MCAO) followed by reperfusion. Changes in m6A RNA modification were evaluated by colorimetric quantification. The expression of the m6A methyltransferases METTL3, METTL14, and WTAP, and the demethylases FTO and ALKBH5 were determined using qPCR and western blot analyses. FTO was overexpressed in brain tissues via intracerebroventricular injection of adenoviruses encoding FTO. The protective effect of FTO on m6A RNA modification and cerebral I/R injury was assessed. MeRIP assays were used to detect the impact of FTO overexpression on m6A modification of pri-miR-155; qPCR analysis was used to identify its maturation. Finally, the role of miR-155 overexpression in the protective effects of FTO on cerebral I/R injury was examined. m6A levels of total RNA were increased, and m6A methyltransferase FTO expression was decreased in post-I/R injury cerebral tissues. FTO overexpression reversed the increase in m6A RNA modification and attenuated cerebral I/R injury. Furthermore, FTO overexpression increased the m6A modification of pri-miR-155 and enhanced its maturation to form miR-155. Notably, miR-155 overexpression blunted FTO's protective effect against cerebral I/R injury. We propose that downregulation of FTO expression contributes to increased m6A RNA modification in cerebral I/R injury. FTO overexpression reverses increased total m6A RNA modification and exerts a protective effect against cerebral I/R injury via downregulating m6A modification of pri-miR-155 to inhibit its maturation process. [ABSTRACT FROM AUTHOR]

The carbon nanotube (CNT) cold cathode can provide a high current and current density for microwave devices, which normally work under pulse mode. In this work, we studied the electron emission characteristics and strucutre stability of a CNT cold cathode in millisecond pulse mode. Peak current and average current are both key parameters for the performance of cold cathode. Increasing the duty ratio proved an effective way to increase the average current and average power of the cold cathode. The pulsing field emission characteristics of CNT cold cathode was optimized by modulating the pulse width, pulse interval time, and duty ratio. The average current in millisecond pulse mode was three orders of magnitude greater than that when using microsecond pulses. The average current also linearly increased with the duty ratio. The morphology of CNT films after pulsing and DC field emission was investigated to reveal the stability and the vacuum breakdown mechanism. The thermal equilibrium of the CNT was analyzed to reveal its underlying mechanism. This work provides a practical strategy for the application of CNT cold cathodes in high-power microwave devices. • Carbon nanotube cold cathode has excellent pulsing field emission characteristics in millisecond domain. • Increasing the duty ratio is an effective way to increase the average current and average power of the cold cathode. • CNT cold cathode driven by millisecond pulse voltage has larger average field emission current and better structure stability. • The structure of CNT film keeps safe when working in high current in pulse-operation mode. • The pulse-operation mode in field emisison helps the thermal equilibrium of the CNT. [ABSTRACT FROM AUTHOR]