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As representative underactuated and nonlinear systems, tower crane involves the multi-direction movement of the payload and even shows a more complex double pendulum in many actual situations, which makes the control problem more complicated. Most anti-swing controllers are mainly based on the linear design of tower crane dynamics at present and are insensitive to the position far from the equilibrium point. The time-varying cable length and double-pendulum effect are not taken into account simultaneously. Aiming at the problem of anti-swing control, a dynamic model of time-varying cable length tower crane with double-pendulum effect is established and an adaptive control method is proposed, which used the adaptive mutation strategy to update the mutation factor in real-time, and the parameters of the controller are tuned by an improved differential evolutionary algorithm. The simulations and experiments are carried out to verify the better optimization ability and faster convergence speed of the improved evolutionary algorithm in the process of parameter tuning and the effectiveness and superiority of the proposed control method are verified by comparing it with PID (proportion integration differentiation) and LQR (linear quadratic regulator) controllers.

Determining how to stimulate public employees’ voice behaviors has become a critical issue in both theory and practice. This article draws on the theories of participative management, leadership, role theory, and social identity theory and proposes a moderated mediation model to explore the mechanism by which participative leadership shapes public employees’ voice behaviors. To test this study’s hypotheses, we conduct a three-wave investigation of 739 public tax agency employees in the Yangtze River Delta area of China. The results show that participative leadership significantly predicts employees’ voice behaviors by enhancing their organizational identification. Furthermore, power distance moderates the relationship between participative leadership and organizational identification. These findings advance our understanding of how to motivate employees’ voice behaviors from the perspective of participative leadership in public organizations.

•Industrial carbide slag is suitable as skeleton material for SSPCM fabrication.•Sample CC6 with mass fraction 50% of carbide slag reached the optimal performance.•Carbide slag has chemical compatibility with sodium nitrate.•Sample CC6 achieved a TES density of 447 KJ/kg in the range of 100–400 °C.•Sample CC6 remains excellent thermal stability after the 3700 heating/cooling cycles.

Although multiple axon guidance cues have been discovered in recent years, little is known about the mechanism by which the spatiotemporal expression patterns of the axon guidance cues are regulated in vertebrates. We report that a homeobox gene Irx4 is expressed in a pattern similar to that of Slit1 in the chicken retina. Overexpression of Irx4 led to specific downregulation of Slit1 expression, whereas inhibition of Irx4 activity by a dominant negative mutant led to induction of Slit1 expression, indicating that Irx4 is a crucial regulator of Slit1 expression in the retina. In addition, by examining axonal behavior in the retinas with overexpression of Irx4 and using several in vivo assays to test the effect of Slit1, we found that Slit1 acts positively to guide the retinal axons inside the optic fiber layer (OFL). We further show that the regulation of Slit1 expression by Irx4 is important for providing intermediate targets for retinal axons during their growth within the retina.

Abstract Regional stream sediment surveys at a 1:200,000 scale reveal positive and negative regional multi‐element geochemical anomalies over medium to large copper‐polymetallic orefields of different genetic types in China. Regional geochemical anomalies of orefield refer to those geochemical anomalies that are related to metallogenesis of an orefield in a certain area. The anomaly area is typically 10 to 100 km2. The regional multi‐element anomalies related to mineralization can be divided into three groups, that is, the ore‐element anomaly association, indicator element anomaly association, and metallogenic environmental element anomaly association. Their common spatial distributions over ore deposits or orefields possess unique structures.

To study the dynamic changes of CT perfusion parameters during the first 12 h in the embolic cerebral ischemia models. Local cerebral ischemia model were established in 7 New Zealand white rabbits. All CT scans were performed with a GE Lightspeed 16 multislice CT. Following the baseline scan, further CT perfusion scans were performed at the same locations 20 min, 1–6 h and 8, 10 and 12 h after the embolus delivery. Maps of all parameters were obtained by CT perfusion software at each time point. The brains, taken 12 h after the scan, were sliced corresponding to the positions of the CT slices and stained by 2,3,5-triphenyltetrazolium chloride (TTC). On the basis of the TTC results, the ischemic sides were divided into 3 regions: core, penumbra and the relatively normal region. The changes of all parameters were then divided into 3 stages. In the first two hours (the first stage), the CBV dropped more remarkably in the core than in the penumbra but rose slightly in the relatively normal region while the CBF decreased and MTT, TTP extended in all regions to varying degrees. In the 2nd–5th h (the second stage), all the parameters fluctuated slightly around a certain level. In the 5th–12th h (the third stage), the CBV and CBF dropped, and MTT and TTP were prolonged or shortened slightly in the core and penumbra though much notably in the former while the CBV, CBF rose and MTT, TTP were shortened remarkably in the relatively normal region. We experimentally demonstrated that the location and extent of cerebral ischemia could be accurately assessed by CT perfusion imaging. The pathophysiology of the ischemia could be reflected by the CT perfusion to varying degrees.