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MicroRNAs (miRNAs) are a class of small, well-conserved noncoding RNAs that regulate gene expression post-transcriptionally. They have been demonstrated to regulate a lot of biological pathways and cellular functions. Many miRNAs are dynamically regulated during central nervous system (CNS) development and are spatially expressed in adult brain indicating their essential roles in neural development and function. In addition, accumulating evidence strongly suggests that dysfunction of miRNAs contributes to neurological diseases. These observations, together with their gene regulation property, implicated miRNAs to be the key regulators in the complex genetic network of the CNS. In this review, we first focus on the ways through which miRNAs exert the regulatory function and how miRNAs are regulated in the CNS. We then summarize recent findings that highlight the versatile roles of miRNAs in normal CNS physiology and their association with several types of neurological diseases. Subsequently we discuss the limitations of miRNAs research based on current studies as well as the potential therapeutic applications and challenges of miRNAs in neurological disorders. We endeavor to provide an updated description of the regulatory roles of miRNAs in normal CNS functions and pathogenesis of neurological diseases. [ABSTRACT FROM AUTHOR]

The dynamics of the confinement transition from L mode to H mode (LH) is investigated in detail theoretically via the extended three-wave coupling model describing the interaction of turbulence and zonal flow (ZF) for the first time. Thereinto, turbulence is divided into a positive-frequency (PF) wave and a negative-frequency (NF) one, and the gradient of pressure is added as the auxiliary energy for the system. The LH confinement transition is observed for a sufficiently high input energy. Moreover, it is found that the rotation direction of the limit cycle oscillation (LCO) of PF wave and pressure gradient is reversed during the transition. The mechanism is illustrated by exploring the wave phases. The results presented here provide a new insight into the analysis of the LH transition, which is helpful for the experiments on the fusion devices. [ABSTRACT FROM AUTHOR]

The morphology of the reproductive systems and the coupling mechanism between the male and the female genitalia during copulation in Dioryctria rubella Hampson are described. Differing from those in other genera of Phycitinae moths, the corpus bursae possesses a well-developed signum, and the seminal duct does not exhibit a bulla seminalis, instead arising from the ventral surface of the corpus bursae. The ultrastructural observation shows that the spines on the inner surface of the ductus bursae and the cervix bursa are complementary to that of cornuti on the outer surface of vesica in position and direction, which elucidates the matching mechanism between the ductus bursae and the vesica. The male possesses well-developed scale brushes, which consist of six pairs of overlapped structures. Finally, the morphological differences of scale brushes between D. rubella and other Dioryctria species and related genera, and their function during copulation are discussed. [ABSTRACT FROM AUTHOR]