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Non-Hermitian photonics: Guest editorial
Bioinspired artificial antioxidases for efficient redox homeostasis and maxillofacial bone regeneration
Abstract Reconstructing large, inflammatory maxillofacial defects using stem cell-based therapy faces challenges from adverse microenvironments, including high levels of reactive oxygen species (ROS), inadequate oxygen, and intensive inflammation. Here, inspired by the reaction mechanisms of intracellular antioxidant defense systems, we propose the de novo design of an artificial antioxidase using Ru-doped layered double hydroxide (Ru-hydroxide) for efficient redox homeostasis and maxillofacial bone regeneration. Our studies demonstrate that Ru-hydroxide consists hydroxyls-synergistic monoatomic Ru centers, which efficiently react with oxygen species and collaborate with hydroxyls for rapid proton and electron transfer, thus exhibiting efficient, broad-spectrum, and robust ROS scavenging performance. Moreover, Ru-hydroxide can effectively sustain stem cell viability and osteogenic differentiation in elevated ROS environments, modulating the inflammatory microenvironment during bone tissue regeneration in male mice. We believe this Ru-hydroxide development offers a promising avenue for designing antioxidase-like materials to treat various inflammation-associated disorders, including arthritis, diabetic wounds, enteritis, and bone fractures.
High-crystallinity and enhanced mobility in In2O3 thin-film transistors via metal-induced method
Meeting the advanced demands of display technology, developing oxide semiconductor thin-film transistors (TFTs) with high mobility remains a significant challenge in current research. This paper reports the fabrication of high-crystallinity In2O3 thin films and high-mobility TFT devices through low-temperature annealing using aluminum (Al) and tantalum (Ta) for induced crystallization. In the control film, partial crystallization occurs only in the central region, with grain lateral dimensions around 50 nm, resulting in a reasonable field-effect mobility of 23.9 cm2/V s for the corresponding TFTs. In contrast, metal-induced films form In2O3 grains with lateral dimensions exceeding 100 nm, along with numerous spherical crystalline particles at the metal/In2O3 interface. The well-defined front-channel structure allows the Al- and Ta-induced In2O3 TFTs to achieve high field-effect mobilities of 65.2 and 101.0 cm2/V s, respectively. Additionally, Al induction improves the subthreshold swing and threshold voltage (Vth), enhancing overall electrical performance. This study investigates the crystallization behavior of induced technology in the In2O3 system, elucidates the mechanism of metal-induced crystallization, and demonstrates that Al-induced crystallization significantly enhances the performance of metal oxide TFTs under processing temperature constraints.
Brucella abortus impairs T lymphocyte responsiveness by mobilizing IL-1RA-secreting omental neutrophils
Significant improvement of energy storage density and efficiency of 0.72Bi0.5Na0.5TiO3-0.28SrTiO3 ceramics and study of the mechanism of high temperature energy storage performance
The energy storage properties of the 0.72Bi0.5Na0.5TiO3-0.28SrTiO3 system have been heavily investigated; however, achieving both high recoverable energy storage density (Wr) and large energy efficiency (η) remains a challenge. In this study, relaxor ferroelectric ceramics exhibiting high Wr and η were prepared by introducing BaSnO3 into 0.9(Bi0.5Na0.5)0.72Sr0.28TiO3-0.1Bi(Mg0.5Ti0.5)O3 relaxor ceramics. A remarkable Wr of 7.5 J/cm3 and η of 91.2% were achieved in the 0.94[0.9(Bi0.5Na0.5)0.72Sr0.28TiO3-0.1Bi(Mg0.5Ti0.5)O3]-0.06BaSnO3 ceramic at an electric field of 460 kV/cm. The η and the energy storage potential (Wr/Eb), respectively, surpass those reported for most ceramics in recent years. The introduction of high-temperature-stable BaSnO3 imparted excellent temperature and frequency stability to the ceramic. The ceramic exhibited a Wr of 3.6 J/cm3 and an η of 79.6% at 160 °C and 265 kV/cm. The sample has a power density of 202.8 MW/cm3, an energy density of 2.2 J/cm3 at an electric field of 260 kV/cm, and a fast charge–discharge capability.
Palmitoylation-dependent regulation of GPX4 suppresses ferroptosis
Second-order topological insulators in Kekulé-patterned hexagonal biphenylene networks
Biphenylene network, a two-dimensional material, has recently been extensively studied, owing to its potential applications. Here, we introduce an experimentally synthesized configuration of hexagonal biphenylene network (h-BPN) as a second-order topological insulator (SOTI). We begin by discussing the higher-order topological origin of h-BPN, which is an extended model of the Kekulé lattice characterized by a multi-node π-conjugation. Through first-principles calculations and tight-binding model, we reveal SOTI in h-BPN, characterized by non-zero fractional corner charges. Furthermore, we show that by varying the number of biphenylene units, h-BPN exhibits adjustable second-order topological phases with alternating parity. Specifically, odd biphenylene indices in the h-BPN system correspond to a SOTI, while even indices result in a trivial insulator. We propose that the h-BPN evolves from the Kekulé lattice. These materials will have important applications in two-dimension devices as higher-order topological materials.
Spatiotemporal transcriptome and metabolome landscapes of cotton somatic embryos
Near-infrared photoluminescence from bismuth, a deep defect in cesium lead bromide perovskite
Bismuth has been investigated as a potential n-type dopant in hybrid lead halide perovskites, but its behavior in all-inorganic perovskites such as CsPbBr3 has not been thoroughly characterized. We show that Bi behaves as a deep defect in CsPbBr3 and gives rise to broad near-infrared emission, similar to its behavior in hybrid perovskites, but a phenomenon not previously reported in CsPbBr3. Using inverse temperature crystallization, we synthesized a series of Bi-doped CsPbBr3 crystals and quantified their Bi concentrations by inductively coupled plasma optical emission spectroscopy. Bi incorporation redshifted the absorption edge, and hybrid density functional theory calculations show that this increased absorption comes from excitation into the deep donor level of Bi, not from narrowing of the bandgap of CsPbBr3. All Bi-doped crystals emitted both narrow band-edge (2.37 eV) and broad defect-level (1.16 eV) photoluminescence, consistent with our theoretical prediction. Time-resolved photoluminescence measurements indicate that Bi incorporation decreases the lifetime of the band-edge emission and gives rise to long-lived defect emission. Power-dependent photoluminescence measurements conducted at 14 K show that the band-edge peak intensity scales as expected for a free or bound exciton, while the sublinear scaling of the infrared defect peak is consistent with recombination between a free hole and a trapped electron, as proposed by theory. These results demonstrate the quantitative accuracy with which current theoretical approaches predict defect behavior in halide perovskites; such theory is key to guiding the experimental development of doping in these materials.
Accelerated enzyme engineering by machine-learning guided cell-free expression
Compact 852 nm Faraday optical frequency standard
Optical clocks with high precision are practical and necessary in atomic physics, geodesy, gravitational wave measurement, etc. Transportability and environmental adaptability are two key indicators to measure the performance of frequency standards. Here, we utilized a highly robust atomic-filter-based Faraday laser as the local oscillator, and achieved two compact Faraday optical frequency standards based on 133Cs6S1/2|F=3⟩→6P3/2|F′=2⟩ and 6S1/2|F=4⟩→6P3/2|F′=5⟩ transitions at 852 nm, leveraging modulation transfer spectroscopy for laser frequency stabilization. The Faraday laser automatically aligns atomic transition spectral lines, due to the use of atomic filters as frequency selective elements. Therefore, the laser wavelength has strong robustness against environmental changes. This setup not only simplifies the operational complexity but also ensures frequency stability. By heterodyne beating between two such compact optical frequency standards, the beatnote achieved a short-term frequency stability of 1.68 × 10−13 at 3 s, remained at the 10−13 level for up to 400 s, and stayed below 2.7 × 10−12 for up to 1600 s, predominantly exhibiting white frequency noise. This underscores the potential of atomic-filter-based Faraday laser in realizing compact and stable frequency standards, mitigating coherent communication error rates, and enhancing the precision of quantum interferometric measurements. Moreover, this approach eliminates the continuous need for external monitoring and adjustments, thereby, offering a practical and robust solution for out of laboratory applications demanding high frequency stability.
Author Correction: The role of manganese in CoMnOx catalysts for selective long-chain hydrocarbon production via Fischer-Tropsch synthesis
Effect of Cr/Al ratio on the microstructure and mechanical properties of CoFeNiCrxAl1−x high-entropy alloys
Achieving strength-ductility and functional integration is a key issue to promote the application of alloys in the field of functional materials. CoFeNiCrxAl1−x alloys exhibit excellent magnetic and corrosion resistance properties; however, their mechanical properties remain underexplored and insufficiently understood. In this work, the microstructure and mechanical properties of CoFeNiCrxAl1−x alloys were investigated, and their intrinsic deformation mechanisms were elucidated. The results indicate that as Cr is gradually replaced by Al, the phase structure transforms from a single-phase face-centered cubic (FCC) structure to a dual-phase FCC and body-centered cubic (BCC), and finally to a BCC/B2 structure. Mechanical tests demonstrated that alloy hardness rises with higher Al content, with the Cr0Al1 alloy exhibiting a hardness approximately 3.3 times greater than that of the Cr1Al0 alloy. Notably, the Cr0.5Al0.5 alloy exhibits an optimal strength-ductility balance, with a yield strength increase in about 60% to 248 MPa and tensile strength increase in about 36% to 610 MPa, while maintaining nearly the same ductility as the Cr1Al0 alloy. The deformation mechanisms were found to be driven by solid solution strengthening due to severe lattice distortion, a high dislocation density resulting from reduced dislocation formation energy, the second-phase strengthening and interface strengthening via the micrometer-scale BCC phase, and twin-induced plasticity induced by the reduced stack fault energy. This work broadens the potential applications of CoFeNiCrxAl1-x alloys as versatile engineering and magnetic functional materials.
Construction and iterative redesign of synXVI a 903 kb synthetic Saccharomyces cerevisiae chromosome
Abstract The Sc2.0 global consortium to design and construct a synthetic genome based on the Saccharomyces cerevisiae genome commenced in 2006, comprising 16 synthetic chromosomes and a new-to-nature tRNA neochromosome. In this paper we describe assembly and debugging of the 902,994-bp synthetic Saccharomyces cerevisiae chromosome synXVI of the Sc2.0 project. Application of the CRISPR D-BUGS protocol identified defective loci, which were modified to improve sporulation and recover wild-type like growth when grown on glycerol as a sole carbon source when grown at 37˚C. LoxPsym sites inserted downstream of dubious open reading frames impacted the 5’ UTR of genes required for optimal growth and were identified as a systematic cause of defective growth. Based on lessons learned from analysis of Sc2.0 defects and synXVI, an in-silico redesign of the synXVI chromosome was performed, which can be used as a blueprint for future synthetic yeast genome designs. The in-silico redesign of synXVI includes reduced PCR tag frequency, modified chunk and megachunk termini, and adjustments to allocation of loxPsym sites and TAA stop codons to dubious ORFs. This redesign provides a roadmap into applications of Sc2.0 strategies in non-yeast organisms.
Realizing p-type InSb with enhanced thermoelectric performance via Cd doping
InSb is a promising mid-temperature thermoelectric material, and its n-type thermoelectric properties have been widely studied. For thermoelectric device applications, it is necessary to have p-type counterparts. Here, we report the realization of p-type InSb with enhanced thermoelectric performance via Cd doping. A high-power factor of 1.91 × 10−3 W m−1 K−2 is obtained in p-type In0.93Cd0.07Sb at 723 K due to the increased carrier concentration. Moreover, the lattice thermal conductivity is decreased to 2.0 W m−1 K−1 owing to the significant multiscale phonon scattering and the suppressed bipolar diffusion effect. Ultimately, the peak zT value of 0.40 is achieved at 723 K in p-type In0.93Cd0.07Sb, which surpasses most contemporary p-type InSb materials. This study demonstrates a simple strategy for fabricating p-type InSb with high performance and holds promise in advancing the development of InSb-based TE devices.
Photocatalytic upcycling of polylactic acid to alanine by sulfur vacancy-rich cadmium sulfide
Temperature stability of multilayer symmetric KNN-based ceramics with continuous phase transitions
Temperature sensitivity of the lead-free piezoelectric ceramics based on potassium sodium niobate (KNN) has posed a significant challenge for practical applications. In this study, we developed a multi-layer symmetric KNN matrix composite ceramic in a strategy of compositional symmetry to enhance the thermal stability of its piezoelectric properties. The optimized piezoelectric properties of d33 and kp can last up to 121 and 105 °C (setting 10% performance reduction as standard), superior to its single composition sample. Importantly, the compositional symmetry effectively addresses the deformation issue during ceramic sintering. This finding of stability in KNN matrix ceramics will facilitate its industrial-scale production processes.
Cryo-electron tomography pipeline for plasma membranes
Abstract Cryo-electron tomography (cryoET) provides sub-nanometer protein structure within the dense cellular environment. Existing sample preparation methods are insufficient at accessing the plasma membrane and its associated proteins. Here, we present a correlative cryo-electron tomography pipeline optimally suited to image large ultra-thin areas of isolated basal and apical plasma membranes. The pipeline allows for angstrom-scale structure determination with subtomogram averaging and employs a genetically encodable rapid chemically-induced electron microscopy visible tag for marking specific proteins within the complex cellular environment. The pipeline provides efficient, distributable, low-cost sample preparation and enables targeted structural studies of identified proteins at the plasma membrane of mammalian cells.
From localization to quantum-dot chains in self-formed core–shell InGaN nanowires emitting in the red
Self-formed core–shell InGaN nanowires (NWs) grown by plasma-assisted molecular beam epitaxy on p-Si (111) are studied by temperature-dependent and time-resolved photoluminescence (PL) spectroscopy. Clear localization and associated photocarrier redistribution can be evidenced by the S-shape temperature dependence of the PL peak energy and inflection of the PL linewidth. An unexpected maximum of the integrated PL intensity as a function of temperature is observed. This maximum is identified as proof that the localized states behave as chains of quantum dots with reduced radiative lifetime due to the combination of strong two-dimensional lateral quantum confinement in the NW core with localization. This is underlined by the time-resolved PL measurements exhibiting a fast, sub-ns, single-exponential decay, in addition evidencing negligible quantum-confined Stark effect for efficient light sources emitting in the red.