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[Objective] The Jinsha River Basin is an important ecological area in the southwestern mountainous gorge region. Predicting and assessing climate and future runoff changes in the Jinsha River Basin under the background of global warming is of great significance for soil and water conservation, flood control, disaster reduction, and water resource planning at the basin scale. [Methods] This study simulates the hydrological processes of the Jinsha River Basin using the VIC model and downscales data from 20 climate models and the Multi-Model Ensemble Average (MMEA) under two emission scenarios (SSP2-4.5, SSP5-8.5) from the CMIP6 global climate models to predict runoff trends from 2015 to 2100. [Results] (1) The historical runoff simulation indicates that the Nash efficiency coefficient between the simulated and observed values exceeds 0.6, and the absolute value of BIAS is controlled within 0.15, demonstrating that the VIC model is suitable for simulating the hydrological process in the Jinsha River Basin. (2) The hydrological process components simulated by the VIC model show that precipitation increases from the upstream to the downstream regions, evapotranspiration is higher in the middle and lower reaches, and the multi-year average values of surface runoff and base flow increase from the upstream to the downstream regions with significant differences, further validating the model's applicability. (3) A comparison of single-model and MMEA simulation results using the EEMD-based (Ensemble Empirical Mode Decomposition) statistical downscaling method reveals that the MMEA matches the observed data the best. Under future SSP2-4.5 and SSP5-8.5 scenarios, the simulation results indicate that hydrological elements change more significantly under the high-radiation and high-emission scenarios (SSP5-8.5), with a particularly noticeable increase in evapotranspiration. [Conclusion] The runoff simulations show that the annual average runoff remains relatively unchanged under the SSP2-4.5 scenario, while it shows a slightly increasing trend under the SSP5-8.5 scenario. Future monthly runoff simulations indicate that most months under the SSP5-8.5 scenario have higher runoff compared to the SSP2-4.5 scenario.

Single-nucleotide variants account for about half of known pathogenic genetic variants in human. Genome editing strategies by reversing pathogenic point mutations with minimum side effects have great therapeutic potential and are now being actively pursued. The emerge of precise and efficient genome editing strategies such as base editing and prime editing provide powerful tools for nucleotide conversion without inducing double-stranded DNA breaks (DSBs), which have shown great potential for curing genetic disorders. A diverse toolkit of base editors has been developed to improve the editing efficiency and accuracy in different context of application. Here, we summarized the evolving of base editors (BEs), their limitations and future perspective of base editing-based therapeutic strategies.

In response to the demand for high-power, long-pulse-width 532 nm lasers in the medical and industrial processing fields, this paper explains how the laser cavity of a high-power Nd:YAG 532 nm laser can be extended while maintaining the laser's q-parameter by using a 4f optical system. The results show that at a repetition rate of 10 kHz, the extended cavity achieved a maximum average power of 112 W. Compared with the short cavity, the power was not significantly reduced. The pulse width was extended from 56 ns to 85 ns, and its broadening ratio reached 46.5%. The laser maintained good beam quality during high-power operation. [ABSTRACT FROM AUTHOR]

Ecological water quantity is the key to ensuring the stability and health of a river ecosystem.However,the traditional ecological flow has poor applicability when it is used to characterize the ecological water quantity of a river in a plain river network area because of the reciprocating flow of water.Therefore,studying methods of characterizing the ecological water quantity of rivers in a plain river network area has important practical significance.After analyzing the characteristics of rivers in a plain river network area,this paper proposes using ecological water level to characterize the ecological water quantity of the rivers in the plain river network area.Taking the Tongyu River as an example,it calculates the ecological water level of the Funing (Tong) section by the wetted perimeter method and the biological space method.The obtained minimum ecological water level of the Funing (Tong) section of the Tongyu River is 0.20 m.The comparison with the requirements of the relevant guiding documents shows that characterizing the ecological water quantity of rivers in a plain river network area by ecological water level is reasonable and that the calculation results are reliable.The research results can provide a new method and idea for the determination and management of the ecological water quantity of rivers in a plain river network area.

Chemically reduced graphene (C- r GO) nanosheets were first prepared from graphene oxide (GO), and then the polypropylene (PP) composites synergistically reinforced–toughened by styrene–butadiene rubber (SBR), and C- r GO nanosheets were fabricated via melt blending. The mechanical properties of PP can be considerably improved by synergistically filling with C- r GO nanosheets and SBR, especially for the notched Izod impact strength (IS). The results from the X-ray diffraction, polarizing optical micrographs, scanning electron microscope, differential scanning calorimetric, dynamic mechanical analysis, and thermogravimetric analysis measurements reveal that: (1) the β -phase crystal structure of the PP is formed when the C- r GO and SBR are synergistically filled with PP and its formation plays a role for the enhancement of the impact strength for PP/SBR/C- r GO composites; (2) the dispersion of the C- r GO and SBR in the PP/SBR/C- r GO composites is homogeneous, indicating that synergistic incorporating method decreases the aggregation of nanosheets and thus increases the sites for dissipation of shock for impact energy in the PP/SBR/C- r GO composites; and (3) the thermal analysis shows high thermal stability for the PP/SBR/C- r GO composites. [ABSTRACT FROM AUTHOR]

A novel PVDF dielectric nanocomposite was achieved by controlling phase morphology and incorporating conductive fillers simultaneously, and the mechanical, thermal, dielectric properties of the resultant dielectric nanocomposites were investigated. Mechanical analysis showed that incorporation of modified MWCNTs (MWCNTs‐COOH) in the PVDF nanocomposites resulted in significant improvements on the tensile strength (Ts) and elasticity modulus (Em). When the filler content was 12 wt%, the Ts of MWCNTs‐COOH/PVDF could reach 64.6 MPa. XRD test showed that the addition of MWCNTs‐COOH and MWCNTs promoted the formation of β‐phase of PVDF. DMA analysis showed that the glass‐transition temperature of the PVDF nanocomposites slightly increases on loading of original MWCNTs and this effect was more pronounced on loading MWCNTs‐COOH. The dielectric property analysis showed that the original MWCNTs were more likely to form local conductive networks in the PVDF matrix, promoting the electron displacement polarization, and improving the dielectric constant. When the contents of MWCNTs was 12 wt%, the percolation threshold was obtained and the dielectric constant (ε′) reached 286, which was 36 times of pure PVDF. Our work provides a simple way to fabricate polymer blends with excellent dielectric performances, good mechanical properties as well as good processing capability but low cost. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48463. [ABSTRACT FROM AUTHOR]