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The van der Waals spin valve, usually consisting of two ferromagnetic layers separated by a nonmagnetic layer, is potentially useful for low-dimensional spintronic devices. Can the spin valve effect be realized in a monolayer van der Waals material? Motivated by the recent synthesis of the MoSi2N4 monolayer and WSi2N4 monolayer, we investigate the spin valve effect in the TiCr2N4 monolayer based on density functional theory and Boltzmann transport theory. The TiCr2N4 monolayer retains a ferromagnetic ground state above room temperature, whose electrical transport property is strongly dependent on the angle of magnetization direction between the two Cr atomic layers. As the angle increases, the conductivity reduces dramatically and results in giant magnetoresistance in the TiCr2N4 monolayer. The serious reduction of conductivity originates from the enlargement of the band gaps, which results in appreciable reduction of the electron group velocity and carriers near the Fermi level. The large difference in conductivity between the TiCr2N4 monolayers with parallel and anti-parallel magnetization makes it an ideal candidate for spin valve devices. Our results reveal the potential opportunities of a ferromagnet with monolayer limitations for spintronics and a unique platform for exploring fundamental physics. [ABSTRACT FROM AUTHOR]

The past two decades have seen a great enhancement of piezoelectric coefficients (d33) to higher than 570 pC/N in (K, Na)NbO3 (KNN) piezoelectrics, but one notoriously unresolved issue is their severe temperature instability, obstructing them toward practical applications. The present work demonstrates a facile approach to overcome this problem by introducing a layered distribution of key dopants (Li and Sb) in a monolithic ceramic, featuring stepwise varied polymorphic phase transition (PPT) temperatures along the thickness direction. The dopant‐graded ceramic exhibits an outstanding d33 of 508 pC/N and a very large piezoelectric strain (Suni, of 0.18%). More importantly, an excellent temperature stability (d33 variation within 13% over the temperature range of 25–150 °C) is achieved, which is superior to that of most state‐of‐art KNN counterparts. These are attributed to the construction of spatially diffused PPT in combination with enhanced polarization, permittivity, and piezoresponse through interfacial effect, including the Maxwell–Wagner effect and intergranular stress by gradient doping. The results offer an alternative strategy for designing high‐performance piezoelectric materials with desirable temperature reliability. [ABSTRACT FROM AUTHOR]

AgNbO3-based antiferroelectric films have attracted emerging attention in the field of dielectric energy storage and possess promising applications in photocatalysis and microwave devices. Unfortunately, it remains a challenge to fabricate pure-phase AgNbO3 films on Si substrates, precluding their further integration into electronic devices. Here, we, for the first time, report phase-pure AgNbO3 films on Pt/Ti/SiO2/Si substrates by a chemical solution deposition (CSD) method. A facile CSD route without using the hazardous pyridine additive is demonstrated to obtain a stable AgNbO3 precursor for spin-coating films. By comprehensively controlling the heat treatment conditions, secondary phases are eliminated in the deposited films. The phase transitions of the AgNbO3 films are also investigated, where intriguingly the room temperature phase is determined to be the antiferroelectric M2 phase, rather than the commonly reported M1 phase in bulk AgNbO3. Meanwhile, the relative dielectric permittivity surpasses 300 at room temperature and maintains at ∼400 with low dielectric loss (<0.05; measured at frequencies of 0.1–1 MHz) over a wide temperature range of 150–350 °C, within a 5% variation. This work provides an easy-to-implement process of AgNbO3 films which may attract scientific interests and potential applications. [ABSTRACT FROM AUTHOR]

How did the great recession affect policy and partisan preferences in the most afflicted countries? We theorize the role of a previously under-emphasized source of preferences: the size and scope of one's exposure to other individuals who have been exposed to the crisis. Contact with others who have economically suffered should be an additional channel for the crisis' effects on policy preferences. We gathered data during the recession from a crisis-hit country, Spain, to measure the size of the respondent's social networks in different ways and the impact of the crisis upon them. We also measured a battery of policy and political preferences (support for austerity, the euro, supranational institutions and new parties). We find strong associations between support for anti-status quo policies and anti-establishment parties and exposure to economic suffering within one's social networks in ways that enrich our understanding of the process of preference formation in times of crisis. [ABSTRACT FROM AUTHOR]

With the development of advanced electrical and electronic devices and the requirement of environmental protection, lead‐free dielectric capacitors with excellent energy storage performance have aroused great attention. However, it is a great challenge to achieve both large energy storage density and high efficiency simultaneously in dielectric capacitors. This work investigates the energy storage performance of sol‐gel‐processed (K,Na)NbO3‐based lead‐free ferroelectric films on silicon substrates with compositions of 0.95(K0.49Na0.49Li0.02)(Nb0.8Ta0.2)O3‐0.05CaZrO3‐x mol% Mn (KNN‐LT‐CZ5‐x mol% Mn). The appropriate amount of Mn‐doping facilitates the coexistence of orthorhombic and tetragonal phases, suppresses the leakage current, and considerably enhances the breakdown strengths of KNN‐LT‐CZ5 films. Consequently, large recoverable energy storage density up to 64.6 J cm−3 with a high efficiency of 84.6% under an electric field of 3080 kV cm−1 are achieved in KNN‐LT‐CZ5‐5 mol% Mn film. This, to the best of our knowledge, is superior to the majority of both the lead‐based and lead‐free films on silicon substrates and thus demonstrates great potentials of (K,Na)NbO3‐based lead‐free films as dielectric energy storage materials. [ABSTRACT FROM AUTHOR]

Previous research has found that children can engage in rectification of pre‐existing inequality by allocating more resources to individuals and groups of disadvantaged status, but less research has investigated how children address the inequalities using resources of different values, especially when they are linked to group membership (i.e., in‐group or out‐group member) in the first‐party (Study 1) and third‐party contexts (Study 2). To address these issues, children aged 5–6 years and 7–8 years were assigned four distribution tasks in each study, in which they were asked to allocate resources of different values to disadvantaged or advantaged persons who were either in‐group or out‐group members and then, reason about their decisions. We found that children used resources of different values to rectify inequalities in the intergroup context overall. Specifically, younger children demonstrated group bias in their rectification of inequalities in both first‐ and third‐party contexts whereas older children overcame group bias and were more concerned about inequality status during allocation. Thus, with age, children were better able to deal with the conflict between inequality status and group bias using resources of different values. [ABSTRACT FROM AUTHOR]

Background: CRISPR-Cas13a is renowned for its precise and potent RNA editing capabilities in cancer therapy. While various material systems have demonstrated efficacy in supporting CRISPR-Cas13a to execute cellular functions in vitro efficiently and specifically, the development of CRISPR-Cas13a-based therapeutic agents for intravesical instillation in bladder cancer (BCa) remains unexplored. Methods: In this study, we introduce a CRISPR-Cas13a nanoplatform, which effectively inhibits PDL1 expression following intravesical instillation. This system utilizes a fusion protein CAST, created through the genetic fusion of CRISPR-Cas13 and the transmembrane peptide TAT. CAST acts as a potent transmembrane RNA editor and is assembled with the transepithelial delivery carrier fluorinated chitosan (FCS). Upon intravesical administration into the bladder, the CAST-crRNAa/FCS nanoparticles (NPs) exhibit remarkable transepithelial capabilities, significantly suppressing PDL1 expression in tumor tissues.To augment immune activation within the tumor microenvironment, we integrated a fenbendazole (FBZ) intravesical system (FBZ@BSA/FCS NPs). This system is formulated through BSA encapsulation followed by FCS coating, positioning FBZ as a powerful chemo-immunological agent. Results: In an orthotropic BCa model, the FBZ@BSA/FCS NPs demonstrated pronounced tumor cell apoptosis, synergistically reduced PDL1 expression, and restructured the immune microenvironment. This culminated in an enhanced synergistic intravesical instillation approach for BCa. Consequently, our study unveils a novel RNA editor nanoagent formulation and proposes a potential synergistic therapeutic strategy. This approach significantly bolsters therapeutic efficacy, holding promise for the clinical translation of CRISPR-Cas13-based cancer perfusion treatments. [ABSTRACT FROM AUTHOR]

Two 3d transition metal high-entropy alloys (3d TM HEAs), AlFeNiVCu and AlFeNiVTi, were suction cast under identical conditions into a cylinder copper mould for investigating the compositional dependence of phase components, microstructures, and compressive properties. The phase components of the AlFeNiVCu were composed of a BCC FeV-rich dendritic phase, a netlike FCC Cu-rich interdendritic phase, and a uniformly distributed B2 AlNi-rich phase, when Cu substituted by Ti the phase components transformed to two BCC solid solution phases of the AlFeNiVTi. Moreover, an outstanding synergy in strength and ductility (ultimate compressive strength: 1936 MPa, plastic strain: 10.0%) was acquired for the AlFeNiVCu, which was sharply contrast with the typically brittle behaviour at the ultimate strength of 108 MPa for the alloy AlFeNiVTi. The distinctions of phase components and morphology were analysed to uncover the conflict in mechanical performance by Cu and Ti mutual substitution in AlFeNiV-base alloys. [ABSTRACT FROM AUTHOR]

Ferroelectric domain walls (DWs) are an important feature of ferroelectric materials and play a vital role in the ferroelectric materials, where charged DWs are a focus of extensive research due to their unique interfacial properties. Herein, epitaxial (K,Na)NbO3 (KNN)‐based thin films are prepared by a sol–gel method, and the monoclinic MC structure of the thin film is confirmed. Stripe‐shaped domain patterns with head‐to‐head and tail‐to‐tail charged DWs in the (110)pc and (1¯10)pc planes are observed in the KNN‐based epitaxial thin film. Although the screening of the bound charges in the charged DWs inevitably increases the energy of the system, the charged DWs in the KNN‐based epitaxial thin film are stabilized by the lattice mismatch strain between the thin film and the substrate. These interesting findings should shed light on the exploration of the functional charged DWs by strain engineering. [ABSTRACT FROM AUTHOR]

A novel 3d transition metal high entropy alloy (3d TM HEA), Al0.5CoCuNiTi, was prepared by arc-melting. The phase component, microstructure, and mechanical properties in as-cast and annealed conditions were investigated. The results showed the phase structures of the studied alloys in both states were composed of FCC and BCC. The BCC phase was the absolute primary phase with a volume fraction of 84%. The FCC phase corresponded to Cu-rich regions, forming a continuous interdendritic regions wrapping the BCC dendrites. Compared to the majority of the reported single-phase FCC 3d TM HEAs, the alloys under both conditions possessed a promising trade-off in strength and plasticity. Specifically, the yield strength (σ0.2) was 1130 and 996 MPa for the as-cast and annealed states, respectively. The compressive strain was more than 15% in both states. In the present work, the combination of phase constitution, morphology, and solid-solution strengthening was performed to justify the mechanical behaviour. [ABSTRACT FROM AUTHOR]

The rapid progress in microelectronic devices has brought growing focus on fast charging-discharging capacitors utilizing dielectric energy storage films. However, the energy density of these dielectric films remains a critical limitation due to the inherent negative correlation between their maximum polarization (P max) and breakdown strength (E b). This study demonstrates enhanced energy storage performance in multilayer films featuring an ultra-thin layer structure. The introduction of a greater number of heterogeneous interfaces improves E b , while lattice distortion and phase transitions, facilitated by diffusion and strain at interfaces, contribute significantly to the enhancement of P max. Remarkably, an energy density of 65.8 J/cm3 with an efficiency of 72.3% was achieved in a 6.7 nm-per-layer BiFeO 3 /SrTiO 3 multilayer configuration, surpassing the performance of most multilayer films composed of simple constituents. This ultra-thin multilayer structure, which simultaneously promoted P max and E b , provides a promising avenue for the development of high-performance dielectric materials. [Display omitted] • Ultra-thin multilayer configuration is constructed based on simple BiFeO 3 and SrTiO 3 constituents. • Confined polarization and multiphase coexistence are induced in ferroelectric layers as thin as 6.7 nm. • The enhanced energy density 65.8 J/cm3 and the efficiency 72.3% surpass most simple-composed multilayer films. • The energy performance is enhanced at both high and low electric fields by ultra-thin strategy. [ABSTRACT FROM AUTHOR]