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As a friendly tool, the soft gripper can be used directly for grasping vulnerable objects in underwater environments. These tasks are generally performed by teleoperation based on the visual feedback, rather than the soft actuators' sensing information. However, vision sensors' function may be restricted in some complex underwater environments with poor visibility and narrow spaces. This will greatly reduce the efficiency of the underwater operations. Therefore, soft actuators strongly require an organism‐like perception system to sense environmental stimuli and can be applied to complex underwater environments. To address the problem, a multidirectional external perception soft actuator based on two flexible optical waveguide sensors is developed and machine learning methods are utilized to build its perceptual model herein. The experimental results indicate that the soft actuator can recognize 12 contact positions based on the sensing model, and the identifying accuracy is up to 99.82%. Additionally, according to the contact location feedback, teleoperation can be more efficiently completed in unknown underwater environments. [ABSTRACT FROM AUTHOR]

Primary spinal cord astrocytoma (SCA) is a rare disease. Knowledge about the molecular profiles of SCAs mostly comes from intracranial glioma; the pattern of genetic alterations of SCAs is not well understood. Herein, we describe genome‐sequencing analyses of primary SCAs, aiming to characterize the mutational landscape of primary SCAs. We utilized whole exome sequencing (WES) to analyze somatic nucleotide variants (SNVs) and copy number variants (CNVs) among 51 primary SCAs. Driver genes were searched using four algorithms. GISTIC2 was used to detect significant CNVs. Additionally, recurrently mutated pathways were also summarized. A total of 12 driver genes were identified. Of those, H3F3A (47.1%), TP53 (29.4%), NF1 (19.6%), ATRX (17.6%), and PPM1D (17.6%) were the most frequently mutated genes. Furthermore, three novel driver genes seldom reported in glioma were identified: HNRNPC, SYNE1, and RBM10. Several germline mutations, including three variants (SLC16A8 rs2235573, LMF1 rs3751667, FAM20C rs774848096) that were associated with risk of brain glioma, were frequently observed in SCAs. Moreover, 12q14.1 (13.7%) encompassing the oncogene CDK4 was recurrently amplified and negatively affected patient prognosis. Besides frequently mutated RTK/RAS pathway and PI3K pathway, the cell cycle pathway controlling the phosphorylation of retinoblastoma protein (RB) was mutated in 39.2% of patients. Overall, a considerable degree of the somatic mutation landscape is shared between SCAs and brainstem glioma. Our work provides a key insight into the molecular profiling of primary SCAs, which might represent candidate drug targets and complement the molecular atlas of glioma. © 2023 The Pathological Society of Great Britain and Ireland. [ABSTRACT FROM AUTHOR]

Complexation between a viologen radical cation (V.+) and cyclobis(paraquat‐p‐phenylene) diradical dication (CBPQT2(.+)) has been investigated and utilized extensively in the construction of mechanically interlocked molecules (MIMs) and artificial molecular machines (AMMs). The selective recognition of a pair of V.+ using radical‐pairing interactions, however, remains a formidable challenge. Herein, we report the efficient encapsulation of two methyl viologen radical cations (MV.+) in a size‐matched bisradical dicationic host — namely, cyclobis(paraquat‐2,6‐naphthalene)2(.+), i.e. CBPQN2(.+). Central to this dual recognition process was the choice of 2,6‐bismethylenenaphthalene linkers for incorporation into the bisradical dicationic host. They provide the space between the two bipyridinium radical cations in CBPQN2(.+) suitable for binding two MV.+ with relatively short (3.05–3.25 Å) radical‐pairing distances. The size‐matched bisradical dicationic host was found to exhibit highly selective and cooperative association with the two MV.+ in MeCN at room temperature. The formation of the tetrakisradical tetracationic inclusion complex — namely, [(MV)2⊂CBPQN]4(.+) – in MeCN was confirmed by VT 1H NMR, as well as by EPR spectroscopy. The solid‐state superstructure of [(MV)2⊂CBPQN]4(.+) reveals an uneven distribution of the binding distances (3.05, 3.24, 3.05 Å) between the three different V.+, suggesting that localization of the radical‐pairing interactions has a strong influence on the packing of the two MV.+ inside the bisradical dicationic host. Our findings constitute a rare example of binding two radical guests with high affinity and cooperativity using host‐guest radical‐pairing interactions. Moreover, they open up possibilities of harnessing the tetrakisradical tetracationic inclusion complex as a new, orthogonal and redox‐switchable recognition motif for the construction of MIMs and AMMs. [ABSTRACT FROM AUTHOR]

Bi2O2X and Bi2OX2 (X = S, Se, and Te) have shown potential for thermoelectric, optoelectronic, etc. applications. The ground‐state structures of Bi2O2X have been determined experimentally (in space group I4/mmm). However, for Bi2OX2, only Bi2OS2 has been synthesized in the experiment (in space group P4/nmm). In previous theoretical studies, the crystal structures of Bi2OSe2 and Bi2OTe2 are assumed the same as that of Bi2OS2. Whether they can be experimentally synthesized remains an open question. Here, a swarm intelligence‐based structural prediction is employed in combination with first‐principles calculations to predict the crystal structures of Bi2OSe2. Three thermodynamically stable low‐energy phases (P21/m, P4/nmm, and P21/m′) are identified. Importantly, the newly reported P21/m phase, instead of the previously assumed P4/mmm phase, has the lowest energy. The P21/m‐Bi2OSe2 shows marginal stability with respect to decomposition into binary compounds Bi2O3 and Bi2Se3. The predicted phases of Bi2OSe2 have bandgaps of 0.67–1.19 eV and comparable small electron and hole carrier effective mass (less than 0.65 m0). The different phase stability between Bi2OSe2 and Bi2OS2 are explained in terms of different Bi─S and Bi─Se covalent bonding characters. Our work provides theoretical guidance for discovering new phases of Bi2OSe2 and an in‐depth understanding of the structure‐property relationship of Bi─O─S/Se system. [ABSTRACT FROM AUTHOR]

Summary: This article studies the static output feedback (SOF) secure control issue for cyber‐physical systems against replay attacks. The fundamental purpose focuses on how to stabilize the closed‐loop system regardless of whether the replay attacks occur. First, a detection scheme is presented that can find the behavior of the adversary and recognize which sensor suffers from the attacks. Then, the SOF controller is designed and the adverse influence induced by the replay attacks can be eliminated through the detection information. Thereafter, a sufficient condition has been established which guarantees the closed‐loop system is stable and satisfies a prescribed H∞ performance. Finally, simulation results verify the effectiveness and superiority of the presented design and detection scheme. [ABSTRACT FROM AUTHOR]

Summary: In this article, an adaptive fuzzy output feedback control method is presented for nonlinear time‐delay systems with time‐varying full state constraints and input saturation. To overcome the problem of time‐varying constraints, the integral barrier Lyapunov functions (IBLFs) integrating with dynamic surface control (DSC) are applied for the first time to keep the state from violating constraints. The effects of unknown time delays can be removed by using designed Lyapunov‐Krasovskii functions (LKFs). An auxiliary design system is introduced to solve the problem of input saturation. The unknown nonlinear functions are approximated by the fuzzy logic systems (FLS), and the unmeasured states are estimated by a designed fuzzy observer. The novel controller can guarantee that all signals remain semiglobally uniformly ultimately bounded and satisfactory tracking performance is achieved. Finally, two simulation examples illustrate the effectiveness of the presented control methods. [ABSTRACT FROM AUTHOR]

Abstract: Recently, research on nonfullerene acceptors in organic solar cells has gradually become a hot topic due to such superior characteristics of light absorption and energy‐level‐convenient manipulation, multiformity of the photoactive material structures, as well as the extensive area in production compared to the fullerene derivatives. However, the nonfullerene acceptors evolved slowly before 2012 and, as a matter of fact, the power conversion efficiency values could only bear 2.0%. Strikingly, nonfullerene acceptors have developed at a fast pace since 2013, with the best device performance of 13.1% now. In this review, recent research progress on nonfullerene acceptors, including small molecules and polymers, are sorted and summarized on the basis of the different characteristics. [ABSTRACT FROM AUTHOR]

Abstract: High crystallinity and compactness of the active layer is essential for metal‐halide perovskite solar cells. Here, a simple pseudohalide‐induced film retreatment technology is developed as the passivation for preformed perovskite film. It is found that the retreatment process yields a controllable decomposition‐to‐recrystallization evolution of the perovskite film. Corresponding, it remarkably enlarges the grain size of the film in all directions, as well as improving the crystallinity and hindering the trap density. Meanwhile, owing to an intermediate catalytic effect of the pseudohalide compound (NH4SCN), no crystal orientation changing and no impurity introduction in the modified film. By integrating the modified perovskite film into the planar heterojunction solar cells, a champion power conversion efficiency of 19.44% with a stabilized output efficiency of 19.02% under 1 sun illumination is obtained, exhibiting a negligible current density–voltage hysteresis. Moreover, such a facile and low‐temperature film retreatment approach guarantees the application in flexible devices, showing a best power conversion efficiency of 17.04%. [ABSTRACT FROM AUTHOR]

This study considers the distributed fault‐tolerant consensus problem for uncertain multi‐agent systems using adaptive protocol. A more general time‐varying actuator fault model is given, which includes loss of effectiveness, stuck, bias and outage fault. A new distributed adaptive control scheme is developed to compensate the effect of fault, multiple delayed state perturbations, mismatched parameter uncertainties and external disturbances on leader–follower multi‐agent systems. Based on the local state information of neighbouring agents, the adaptive updating protocol gains are adjusted online, which remove the assumption that the upper bounds of unknown uncertainty, delayed state perturbation and external disturbances should be known. Moreover, the consensus errors of leader–follower systems can asymptotically converge to zero. Finally, a simulation example is given to show the effectiveness of the theoretical analysis. [ABSTRACT FROM AUTHOR]

SUMMARY This paper addresses the design problem of fault-tolerant H ∞ controller for linear systems with state quantization. By combining linear matrix inequality technique and indirect adaptive method, a new method is proposed to design a fault-tolerant controller against actuator faults via quantized state feedback. The controller gains are updating according to the online estimation of eventual faults, which are dependent on the quantized state signals. Meanwhile, the proposed designs conditions with variable gains can be proved to be less conservative than those of the traditional controller with fixed gains. A numerical example is presented to illustrate the effectiveness of the proposed method. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Solution-processable polymers consisting of perylene diimide (PDI) acceptor moieties alternating with dithienothiophene (DTT), N-dodecyl-dithienopyrrole (DTP), or oligomers of these donor groups have been synthesized. We have, in addition to varying the donor, varied the N,N′ substituents of the PDIs. The thermal, optical, electrochemical, and charge-transport properties of the polymers have been investigated. The polymers show broad absorption extending from 300 to 1000 nm with optical band gaps as low as 1.2 eV; the band gap decreases with increasing the conjugation length of donor block, or by replacement of DTT by DTP. The electron affinities of the polymers, estimated from electrochemical data, range from −3.87 to −4.01 eV and are slightly affected by the specific choice of donor moiety, while the estimated ionization potentials (−5.31 to −5.92 eV) are more sensitive to the choice of donor. Bottom-gate top-contact organic field-effect transistors based on the polymers generally exhibit n-channel behavior with electron mobilities as high as 1.7 × 10-2 cm2/V/s and on/off ratios as high as 106; one PDI-DTP polymer is an ambipolar transport material with electron mobility of 4 × 10-4 cm2/V/s and hole mobility of 4 × 10-5 cm2/V/s in air. There is considerable variation in the charge transport properties of the polymers with the chemical structures. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 [ABSTRACT FROM AUTHOR]

A new solution-processable acceptor-acceptor conjugated copolymer ( P1) based on perylene diimide (PDI) incorporating planar electron-deficient fluorenone was synthesized by palladium(0)-catalyzed Suzuki coupling reaction. Relative to the donor-acceptor conjugated copolymer ( P2) of PDI and dithienothiophene, polymer P1 exhibits 0.1 eV down shift of lowest unoccupied molecular orbital (LUMO) level, 70 nm blue shift of low-energy absorption band, and 0.36 eV increase of optical band gap. Polymer P1 in top-contact bottom-gate organic field-effect transistors exhibits a saturation electron mobility of 0.01 cm2/(V s) in air, while P2 does not function in the same device in air. The better air stability of P1 is attributed to a more dense packing of the polymer chains excluding oxygen or water and lower LUMO level of P1. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 [ABSTRACT FROM AUTHOR]

Binding stoichiometry, host-guest systems, molecular recognition, radical-pairing interactions Keywords: binding stoichiometry; host-guest systems; molecular recognition; radical-pairing interactions EN binding stoichiometry host-guest systems molecular recognition radical-pairing interactions 25583 25583 1 11/17/21 20211122 NES 211122 B Selective recognition b of two stacked viologen radical cations in solution using a size-matched radical host is reported by J. Fraser Stoddart and co-workers in their Research Article on page 25454. By employing 2,6-bismethylenenaphthalene as the linker, the bisradical dicationic host is able to accommodate two methyl viologen radical cation guests with strong and cooperative binding. [Extracted from the article]

Keywords: binding stoichiometry; host-guest systems; molecular recognition; radical-pairing interactions EN binding stoichiometry host-guest systems molecular recognition radical-pairing interactions 25787 25787 1 11/17/21 20211122 NES 211122 B Die selektive Erkennung b von zwei gestapelten Viologen-Radikalkationen in Lösung unter Verwendung eines größenangepassten radikalischen Wirts wird von J. Fraser Stoddart et al. in der Zuschrift auf S. 25658 beschrieben. Binding stoichiometry, host-guest systems, molecular recognition, radical-pairing interactions Durch die Verwendung von 2,6-Bismethylennaphthalin als Linker ist der bisradikalische dikationische Wirt in der Lage, zwei Methylviologen-Radikalkationen als Gäste mit starker und kooperativer Bindung aufzunehmen. [Extracted from the article]

To eliminate the toxic Pb2+ cation in hybrid halide perovskites, M′3+ cations of Bi/Sb‐based layered halide perovskites are being increasingly investigated for optoelectronic applications. However, such M′3+ trivalent cations constrain the face‐sharing bioctahedral or the bi‐layered perovskites required to meet the charge neutrality condition. This usually gives rise to oversized indirect bandgaps and inferior carrier transport. Recent experiment suggested a mixed‐cation tri‐layered halide perovskite can be obtained by sandwiching a [Cu2+X6]4− layer between Sb3+ perovskite bilayers along the polar [111] planes with cation ordering. A material design of mixed‐cation <111>‐oriented tri‐layered Pb‐free halide perovskite A4MM′2X12 is studied by a computational screening of various combinations of M2+ cations (e.g., Zn2+, Sn2+) and M′3+ cations (e.g., Bi3+, Sb3+). The thermodynamic stability of the candidate materials is systemically evaluated with respect to potential decomposition pathways and a series of stable compounds is synthesized. These results further indicate the chemical trend of electronic structure and how octahedral tilting coupling with charge ordering affects electronic properties. A protocol for engineering A4MM′2X12 perovskites with optimized structures and electronic properties by exploiting octahedral tilting coupling with charge ordering in the polar <111> layered perovskites is established. [ABSTRACT FROM AUTHOR]