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DNA compaction is required for the condensation and resolution of chromosomes during mitosis, but the relative contribution of individual chromatin factors to this process is poorly understood. We developed a physiological, cell-free system using high-speed Xenopus egg extracts and optical tweezers to investigate real-time mitotic chromatin fiber formation and force-induced disassembly on single DNA molecules. Compared to interphase extract, which compacted DNA by ~60%, metaphase extract reduced DNA length by over 90%, reflecting differences in whole-chromosome morphology under these two conditions. Depletion of the core histone chaperone ASF1, which inhibits nucleosome assembly, decreased the final degree of metaphase fiber compaction by 29%, while depletion of linker histone H1 had a greater effect, reducing total compaction by 40%. Compared to controls, both depletions reduced the rate of compaction, led to more short periods of decompaction, and increased the speed of force-induced fiber disassembly. In contrast, depletion of condensin from metaphase extract strongly inhibited fiber assembly, resulting in transient compaction events that were rapidly reversed under high force. Altogether, these findings support a speculative model in which condensin plays the predominant role in mitotic DNA compaction, while core and linker histones act to reduce slippage during loop extrusion and modulate the degree of DNA compaction.

Organic electrode materials have exhibited good electrochemical performance in batteries, but their voltages and rate capabilities still require improvement to meet the increasing demand for batteries with high energy and power density. Herein, we design and synthesize a branched dihydrophenazine-based polymer (p-TPPZ) as a cathode material for dual-ion batteries (DIBs) through delicate molecular design. Compared with the linear dihydrophenazine-based polymer (p-DPPZ, with a theoretical capacity of 209 mAh g–1), p-TPPZ possessed a higher theoretical capacity of 233 mAh g–1 and lower highest occupied molecular orbital energy levels, which resulted in a high actual capacity (169.3 mAh g–1 at 0.5 C), an average discharge voltage of 3.65 V (vs. Li+/Li) and a high energy density (618.2 Wh kg–1, based on the cathode materials). The branched structure of p-TPPZ led to a larger specific surface area than that of p-DPPZ, which was beneficial for the electrolyte infiltration and fast ionic transport, contributing to the high power density. Due to the fast reaction kinetics, even at a power density of 23, 725 W kg–1 (40 C), the energy density still reached 474.5 Wh kg–1. We also made a detailed investigation of the p-TPPZ cathode's charge storage mechanism. This work will stimulate the further molecular design to develop organic batteries with both high energy and power density.

In this article, an adaptive repetitive learning control (ARLC) scheme is proposed for permanent magnet synchronous motor (PMSM) servo systems with bounded nonparametric uncertainties, which are divided into two separated parts. The periodically nonparametric part is involved in an unknown desired control input, and a fully saturated repetitive learning law with a continuous switching function is developed to ensure that the estimate of the unknown desired control input is continuous and confined with a prespecified region. The nonperiodically nonparametric part is transformed into the parametric form and compensated by designing the adaptive updating laws, such that a prior knowledge on the bounds of uncertainties is not required in the controller design. With the proposed ARLC scheme, a high steady-state tracking accuracy is guaranteed, and comparative experiments are provided to demonstrate the effectiveness and superiority of the proposed method.

Two-dimensional (2D) silicate materials have become one of the promising candidates for constructing composite polymer electrolytes due to their advantages of low cost, high stability, good mechanical property, high ionic conductivity and potential to inhibit the growth of lithium dendrites. However, the application of 2D silicate materials in composite polymer electrolytes (CPEs) is still at the infancy stage and facing a lot of challenges. In this minireview, we summarize the structures and properties of 2D silicate materials that have been applied in CPEs, the processing methods of composite electrolytes based on 2D silicates, and the recent process of 2D silicate materials in CPEs. We hope this review could present a general overview of the 2D silicates for CPEs and promote the further study for potential applications.

In spectrum sharing systems based on spectrum trading, user locations are vital for the efficiency of dynamic channel reuse. However, both primary users (PUs) and secondary users (SUs) undertake the risk of location information leakage: a malicious PU may illegally collect SUs’ location information to manipulate market decisions; a malicious SU would threat a PU’s operational privacy by inferring the PU’s location through seemingly inoffensive queries. To protect both PUs’ and SUs’ location information in spectrum trading, a bilateral privacy preservation framework is introduced in this paper. A game-theoretic approach based on the Stackelberg model is proposed to achieve the tradeoff between the privacy-preserving level and user utility. With the proposed approach, both PUs and SUs can maximize their utilities while maintaining their location privacy to desired levels. Simulation results demonstrate that the proposed approach can effectively enhance user utility gain and strengthen user privacy guarantee by flexibly adjusting their privacy levels in practice.

This article concerns studies on finite-time systems (FTSs), which are expected for high-level system synthesis. An FTS usually obeys an attracting law (AL), under which the dynamics of the FTS is governed. This article probes into the analysis of finite-duration convergence of the power-rate ALs, and especially on the estimation for the bound of their settling time functions, without selecting the transition state to be one. It is shown that the settling time is a function of the initial state, and the value of the function varies with the initial state. The existence of the upper bound of the function assures that the duration over which the settling time varies is finite with respect to the initial state. The estimate depends on the transition state, revealing that the bound on the settling time cannot be determined by a certain value, as different transition states are chosen. The optimal transition state in certain sense is acquired in this article, and the comparison is made between the existing estimation and the optimal one. Furthermore, we concern ourselves with the two-phase AL (TPAL) also without fixing the transition state, for which we are able to give an accurate bound of its settling time function. To illustrate the usefulness of the TPAL, we present a finite-duration learning control approach which utilizes the merits of the exiting control methods in coping with both time-varying parametric and nonparametric uncertainties.

The oxidation of π-d-conjugated coordination polymers (CCPs) accompanied with anion insertion has the merits of increasing the capacity and elevating the discharge voltages. However, previous reports on this mechanism either required more investigations or showed low capacity and poor cyclablity. Herein, triphenylene-catecholate-based two-dimensional CCPs are constructed by employing inactive transition-metal ions (Zn2+ ) as nodes, forming Zn-HHTP. Substantial characterizations and theoretical calculations indicate the successive storage of cations and anions by redox reactions of only ligands, leading to a high reversible capacity of ≈150 mAh g-1 at 100 mA g-1 and a remarkable capacity retention of 90 % after 1000 cycles. On the contrary, as a control experiment, the analogous CCPs (Cu-HHTP) with Cu2+ nodes, where both ligands and metal ions undergo redox reactions, accompanied by the storage of only Na+ cations, show a much poorer cyclability. These results highlight the importance of redox reactions of only ligands for long-term cycle life and the insight into the storage mechanisms deepens our understanding on CCPs for the further design of CCPs with high performance.

Herein, a heterostructure of MoS2/CdS/TiO2 nanotube arrays is constructed by successive ionic layer adsorption/reaction of CdS and dipping-assembly of MoS2 on the vertically oriented TiO2 nanotubes prepared by anodization method. The heterostructure is extensively investigated in terms of the composition, morphology, structural, and optical properties. It is observed that the co-modification of TiO2 nanotube arrays with CdS and MoS2 significantly enhances the visible light response and boosts the facile photo-generated electrons’ transfer and charge separation efficiencies. Therefore, the prepared heterostructure photo-anode exhibits significantly enhanced photoelectrochemical properties including photocurrent, open circuit potential, and photo-conversion efficiencies compared with that of pure TiO2 nanotube arrays and CdS/TiO2 nanotube systems. Interestingly, it is found that the MoS2 coatings on the surface of CdS/TiO2 nanotube arrays greatly enhance their photoelectrochemical stability. The presented work demonstrates that MoS2/CdS/TiO2 nanotube heterostructures are a promising material for improved photoelectrochemical properties. A heterostructure of MoS2/CdS/TiO2 nanotube arrays was constructed by successive ionic layer adsorption/reaction of CdS and dipping-assembly of MoS2 on the vertically oriented TiO2 nanotube arrays, and their improved photoelectrochemical properties were demonstrated