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Error-free mitosis depends on accurate chromosome attachment to spindle microtubules, powered congression of those chromosomes, their segregation in anaphase, and assembly of a spindle midzone at mitotic exit. The centromere-associated kinesin motor CENP-E, whose binding partner is BubR1, has been implicated in congression of misaligned chromosomes and the transition from lateral kinetochore-microtubule association to end-on capture. Although previously proposed to be a pseudokinase, here we report the structure of the kinase domain of Drosophila melanogaster BubR1, revealing its folding into a conformation predicted to be catalytically active. BubR1 is shown to be a bona fide kinase whose phosphorylation of CENP-E switches it from a laterally attached microtubule motor to a plus-end microtubule tip tracker. Computational modeling is used to identify bubristatin as a selective BubR1 kinase antagonist that targets the αN1 helix of N-terminal extension and αC helix of the BubR1 kinase domain. Inhibition of CENP-E phosphorylation is shown to prevent proper microtubule capture at kinetochores and, surprisingly, proper assembly of the central spindle at mitotic exit. Thus, BubR1-mediated CENP-E phosphorylation produces a temporal switch that enables transition from lateral to end-on microtubule capture and organization of microtubules into stable midzone arrays.

Gas-assisted coaxial electrospinning (GACES) is a simple and general method for the mass preparation of coaxial nanofiber membranes, which has great industrial potential. However, in the manufacturing process, due to the bending instability of the jet in the electric field and the pulling effect of the gas flow field, the deposition uniformity of the fiber is still a big problem. Through finite element simulation analysis of the flow field in the manufacturing process and the construction of the jet mechanics model after adding the flow field, the influence mechanism of coaxial auxiliary flow on the fiber deposition area and its uniformity was successfully revealed in this research. Finally, the deposition area and thickness uniformity of coaxial fibers are increased by 3 times (the deposition area: 19.63 cm2 → 78.50 cm2) and 2.34 times (the standard variance: 3 μm2 → 10 μm2) by gas-assisted coaxial electrospinning. At the same time, the coaxial auxiliary gas flow also reduces the coaxial fiber diameter by 36.9% (the average fiber diameter: 241 nm ± 5 nm → 152 nm ± 23 nm) and the distribution range by 66% (the standard variance: 1.5 × 102 nm2 → 51 nm2). This research provides a reliable idea and experimental basis for homogeneous preparation of coaxial nanofiber membranes. [ABSTRACT FROM AUTHOR]

Serpentine microstructures offer excellent physical properties, making them highly promising in applications in stretchable electronics and tissue engineering. However, existing fabrication methods, such as electrospinning and lithography, face significant challenges in producing microscale serpentine structures that are cost-effective, efficient, and controllable. These methods often struggle with achieving precise control over fiber morphology and scalability. In this study, we developed a near-field direct writing (NFDW) technique incorporating piezoelectric micromotion to enable the precise fabrication of serpentine micro-/nanofibers by incorporating micromotion control with macroscopic movement. Modifying the fiber structure allowed for adjustments to the mechanical properties, including tunable extensibility and distinct characteristics. Through the control of the frequency and amplitude of the piezoelectric signal, the printing errors were reduced to below 9.48% in the cycle length direction and 6.33% in the peak height direction. A predictive model for the geometrical extensibility of serpentine structures was derived from Legendre's incomplete elliptic integral of the second kind and incorporated an error correction factor, which significantly reduced the calculation errors in predicting geometric elongation, by 95.85%. The relationship between microstructure bending and biomimetic non-linear mechanical behavior was explored through tensile testing. By controlling the input electrical signals, highly ordered serpentine microstructures were successfully fabricated, demonstrating potential for use in biomimetic mechanical scaffolds. [ABSTRACT FROM AUTHOR]

Due to the impact of natural disasters and public security incidents, the industrial chain is broken, and the economy has declined, especially in western resource-based cities of China where enterprises have closed down, the unemployed have increased sharply, and social contradictions have become prominent. Therefore, the resilience of the industrial structure is an urgent problem to solve in the academic circle and sustainable development. This paper identifies the spatio-temporal evolution characteristics of the resilience of the resource-based cities' industrial structure in western China from 2006 to 2021 to provide a reference for the improvement of their industrial structure resilience. [ABSTRACT FROM AUTHOR]

Multi‐needle electrospinning is a simple and general method for mass preparation of nanofiber membrane, which has great industrial potential. However, the bending instability produced in the electrospinning process makes that the deposition uniformity of the nanofiber is still a big concern, resulting in non‐uniform nanofiber membrane, which seriously affects the application of electrospun membrane in environmental filtration, new energy and medical fields. In order to improve the uniformity of nanofiber deposition in multi‐needle electrospinning, an auxiliary flow field system (AFF) is proposed, which can effectively improve the uniformity of nanofiber deposition. After image processing, the uniformity of nanofiber deposition is quantified with the index of grey distribution, and the effectiveness of this method is verified. Combined with the multi‐physical field analysis, the influence mechanism of cross‐wind field on the uniformity of fibre deposition was revealed. By optimizing the experimental parameters, the non‐uniformity of nanofiber deposition was reduced by 49.19%. Based on multi‐needle electrospinning technology, a reliable idea (AFF) and experimental basis are provided for the uniform preparation of nanofiber membrane. [ABSTRACT FROM AUTHOR]

The establishment of green finance reform and innovation (GFRI) pilot zone is an important measure of the Chinese government to urge enterprises to develop green transformation. This paper explores the impact of pilot policies in the GFRI pilot zone on corporate environmental investment. Based on 819 A-share listed enterprises from 2010 to 2020, our staggered difference-in-differences (staggered DID) estimation documents revealed that enterprises in the GFRI pilot zone significantly increased the corporate environmental investment efficiency but reduced the scale of corporate environmental investment.This conclusion remained robust after Propensity Scores Matching difference-in-differences (PSM-DID), replacing dependent variables, and shortening the time window. We contend that the increased research and development (R&D) expenditure and technological innovation are the potential mechanisms at work. Heterogeneity analysis showed that the establishment of GFRI improved the environmental investment efficiency of polluting enterprises but had no effect on green enterprises.Meanwhile, the effect of GFRI exhibited heterogeneity in the type of enterprise ownership. This paper evaluates the implementation effect of GFRI from the perspective of corporate environmental investment, and provides theoretical support and an empirical basis for green finance policy to serve China's green economy. [ABSTRACT FROM AUTHOR]