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Bismuth‐based materials show great potential in aqueous batteries. But it is difficult to design a bifunctional bismuth‐based material for zinc and ammonium ion batteries (ZIBs and AIBs). Herein, a electrospinning method followed by a selenization strategy is used to design Bi2Se3 nanodots embedded in porous carbon nanofibers. Experimental studies coupled with theoretical calculations prove that the designs of nanodot and Se vacancy improve the transfer and storage of Zn2+ and NH4+. Bi2Se3 nanodots are restricted to porous carbon nanofibers during cyclic test. An insertion‐type mechanism is revealed by ex situ characterizations. As a result, this well‐designed electrode (6 mg cm−2) offers high reversible capacities of 270 mA h g−1 in ZIBs and 192 mA h g−1 in AIBs at 0.05 A g−1 and long‐term cycle life (60% capacity retention at 10 A g−1 after 20 K cycles for ZIBs, 78% capacity retention at 2 A g−1 after 9 K cycles for AIBs). Remarkably, it still displays satisfactory performances even at an ultrahigh mass loading of 18 mg cm−2. Furthermore, Zn2+ and NH4+ full cells offer high reversible capacities of 120 and 90 mA h g−1 at 0.05 A g−1 respectively. This work provides a reference for designing a bifunctional electrode. [ABSTRACT FROM AUTHOR]

This paper proposes a novel second-order predictive disturbance observer for systems experiencing external disturbance with both input and output measurement delays. The proposed observer uses the delayed system state and its derivative information to predict and compensate for future disturbance in real time, despite the delayed control input. Compared with the past studies about second-order disturbance observer, this paper analyses the impact of the disturbance derivatives on the estimation accuracy. This observer is designed using the Lyapunov–Razumikhin theorem and its exponential stability is proven. Comparative analysis and simulations demonstrate its advantages over second-order disturbance observers that do not consider delays. [ABSTRACT FROM AUTHOR]

For input-delayed mechanical system with input amplitude constraints, the consensus control problem of multi-agent system (MAS) based on directed graph topology is studied. For scenarios where only some agents can receive the desired signal, an observer is proposed to enable each agent to observe the desired signal, with exponential convergence of the observation error being proven. In the controller design, the system's input integral in fed back to the controller to eliminate the effects of input delay. By combining the input integral method with the hyperbolic tangent function, the input amplitude in limited while addressing the input delay issue. The FMINCON function in used to optimize the control parameters. Finally, the Lyapunov method in utilized to prove the achievement of control objectives and the asymptotic stability of the closed-loop system. Simulation results demonstrate the effectiveness of the proposed observer and controller n achieving system consensus control. [ABSTRACT FROM AUTHOR]

A predictive disturbance-observer-based controller (DOBC) is proposed for a class of input time-delay mechanical systems with input constraints. A predictive disturbance observer is developed for external disturbance and proof for exponential convergence of estimation error is provided. In the controller design process, the input integral is fed back into the controller to eliminate the effect of input delay, and the input integral method and hyperbolic tangent function are firstly combined to solve the problem of input delay and limit the control input simultaneously. The optimisation function FMINCON of MATLAB is used to obtain control parameters. Control goal realisation and the exponential stability of the closed-loop system are proven via the Lyapunov direct method. Simulation results verify the effectiveness of the proposed controller. [ABSTRACT FROM AUTHOR]

A contact-force control and vibration suppression problem for a constrained one-link flexible manipulator with unknown control direction and time-varying actuator fault is discussed in this paper. The manipulator is described by a Partial Differential Equation model. The Nussbaum function is used to solve the unknown control direction and time-varying actuator fault problems. A Nussbaum function provides an adaptive boundary controller constructed to control the contact force to a target and simultaneously eliminate the vibration of the flexible manipulator. The Variable Separation Technique is used along with system boundary conditions to prove the necessary existence and uniqueness of the system solution more concisely than using the common C 0 -semigroup contractions method. Because force sensors are not necessary, the noise caused by a force sensor can be avoided. Numerical simulations verify the effectiveness of the proposed controller-based solution. [ABSTRACT FROM AUTHOR]

Simple Summary: Prophylactic interventions are critical for BRCA1/2 mutation carriers to reduce the risks of hereditary breast and ovarian cancer (HBOC). This systematic review and meta-analysis synthesizes data on the efficacy of various preventative strategies. The analysis incorporated 21 studies involving risk-reducing surgeries (RRS), chemoprevention, and screening. Findings indicate a substantial reduction in breast and ovarian cancer incidence and mortality among BRCA1/2 carriers following RRS, particularly mastectomy and oophorectomy, compared to chemoprevention. This study underscores the necessity of tailored interventions, especially considering the varied protective effects between BRCA1 and BRCA2 mutation carriers. This review aids in informing clinical decisions and underscores the importance of context-specific uptake rates in cost-effective evaluations. Background: Hereditary breast and ovarian cancers (HBOCs) pose significant health risks worldwide and are mitigated by prophylactic interventions. However, a meta-analysis of their efficacy and the impact of different genetic variants on their effectiveness is lacking. Methods: A systematic review and meta-analysis were conducted, adhering to Cochrane guidelines. The review encompassed studies that involved prophylactic interventions for healthy women with BRCA variants, focusing on cancer incidence and mortality outcomes. The Newcastle–Ottawa Scale was used for risk of bias assessment. We pooled the extracted outcomes using random effects models and conducted subgroup analyses stratified by intervention, variant, and cancer types. Results: A total of 21 studies met the inclusion criteria. The meta-analysis revealed that prophylactic interventions significantly reduced cancer risk and mortality. The subgroup analysis showed a greater protective effect for BRCA2 than BRCA1 variant carriers. Risk-reducing surgeries (RRS) were more effective than chemoprevention, with RRS notably reducing cancer risk by 56% compared to 39% for chemoprevention. Prophylactic oophorectomy significantly reduced HBOC risks, while the effect of prophylactic mastectomy and chemoprevention on mortality was less conclusive. Conclusions: Prophylactic interventions significantly reduce the risk of HBOC and associated mortality. This comprehensive analysis provides insights for future economic evaluations and clinical decision-making in HBOC interventions. [ABSTRACT FROM AUTHOR]

Digital holographic microscopy is an important measurement method for micro-nano structures. However, when the structured features are of high-slopes, the interference fringes can become too dense to be recognized. Due to the Nyquist's sampling limit, reliable wavefront restoration and phase unwrapping are not feasible. To address this problem, the interference fringes are proposed to be sparsified by tilting the reference wavefronts. A data fusion strategy including region extraction and tilt correction is developed for reconstructing the full-area surface topographies. Experimental results of high-slope elements demonstrate the validity and reliability of the proposed method. [ABSTRACT FROM AUTHOR]

Mn chalcogenide cathodes hold great promise for high-capacity applications in aqueous Zinc-ion batteries (AZIBs). However, they face critical challenges, including Mn dissolution and chalcogenide decomposition, which not only degrade performance but also raise environmental concerns. Although the incorporation of reduced graphene oxide (rGO) has shown potential in mitigating these issues, the underlying mechanisms remain unclear. Herein, we synthesize MnSe@rGO composites via a hydrothermal and annealing process, utilizing rGO as a conductive framework to stabilize MnSe nanoparticles and improve the structural integrity and reversibility of the electrode. The resulting composite cathode demonstrates enhanced specific capacity, prolonged cycle life, and robust cycling stability under high current densities. Ex-situ characterizations reveal that rGO effectively suppresses Mn dissolution and prevented Se loss during cycling, thereby maintaining the integrity of the cathode and minimizing corrosion of the Zn anode. Furthermore, first-principles calculations provide deep insights into the interactions at the atomic level, showing that Se-doped rGO exhibits strong adsorption affinity for both Mn 3+ and Se 2- , leading to increased structural stability and reduced side reactions. This study highlights the potential of rGO composites in addressing key challenges in Mn chalcogenide cathodes, paving the way for their practical application in environmentally friendly AZIBs., (© 2024 Wiley-VCH GmbH.)

Adaptive optics (AO) technology can correct wavefront distortion in coherent free space optical communication (FSOC), with wavefront sensors playing a vital role in this process. However, traditional wavefront sensors are large and expensive. Therefore, we propose using the inexpensive and easy-to-deploy flat optics angle-based wavefront sensor (FOA-WFS) to measure the wavefront aberration. It aims to meet the needs of various FSOC applications. We first establish the relationship between the energy ratio and the Zernike coefficient through theoretical studies and analyze the feasibility of applying the FOA-WFS to the FSOC. We then generate experimental datasets based on the relevant principles. Through numerical simulation, we verify that it can reconstruct wavefront aberration accurately and improve system performance. Finally, we analyze the mixing efficiency and bit error rate based on the collected aberration data by the experimental platform. The results indicate that the AO system based on the FOA-WFS can efficiently improve the performance of the FSOC. This study provides a novel wavefront aberration detection method for designing the AO systems in the FSOC.