Matter最新文献

Recent advances in nerve cuff electrodes, which integrate soft electrochemical actuators and neural microelectrodes, offer a minimally invasive method for peripheral nerve interfacing. Utilizing low-voltage electric actuation, these cuffs encircle peripheral nerves in vivo, providing adaptability for chronic and precise nerve monitoring and modulation.

Current mechanical and bioprosthetic heart valve replacements suffer from thrombogenicity or poor durability and do not grow, regenerate, or repair. Tissue-engineered heart valves (TEHVs) may address these limitations using bioresorbable materials that are replaced by host cell-secreted matrices over time in vivo to yield a functional living replacement valve. Despite significant progress over the past three decades, the quest for living heart valve substitutes with functional longevity continues, with new biomaterials and biofabrication technologies emerging to better recapitulate crucial characteristics of native valve tissue. With an emphasis on biomaterials and biofabrication technologies, this review first outlines biomaterials used in heart valve tissue engineering and the role that material properties, such as degradation and mechanical behavior, play in the success of the final valve product. Next, strategies used in the development of TEHVs including scaffolding, assembly, and decellularization are explored. Lastly, the progress of TEHVs toward clinical translation is highlighted.

Structural superlubricity refers to a state with almost vanishing friction and wear between crystalline surfaces in incommensurate configurations. However, thus far, this phenomenon has been observed only at solid-solid interfaces. Here, we constructed an in situ heterojunction between a crystalline boundary tribofilm and a pressure-induced solid-phase 1–dodecanol molecular layer, achieving structural superlubricity in a liquid-solid interface. This novel superlubricity state, termed phase transition structural superlubricity (PTSS), is induced by incommensurate slip at the in situ heterojunction. Atomic force microscopy experiments and molecular dynamics simulations demonstrated that the friction of in situ heterojunction exhibits a periodicity of 180°. Notably, the PTSS arises when the molecular axis of 1–dodecanol is oriented 90° to the direction of friction. These findings provide a novel design strategy for structural superlubricity and bridge the gap between liquid and solid superlubricity, shedding substantial light upon achieving structural superlubricity across a broad range of environments.

The classical central paradigm of structural biology links a protein’s sequence to its structure and function but overlooks conformational fluctuation that is integral to protein function. We propose a graph neural network model based on gated attention that explicitly incorporates protein dynamics via physics-based models to predict protein crystallization propensity. We compare results to all-atom molecular dynamics simulations of flexible, disordered human tropoelastin and ordered, globular human lysyl oxidase-like protein. Our findings show that fluctuating residues correlate with locally maximal attention scores in the neural network. By methodically truncating the sequences, we establish correlations between dynamical and physicochemical molecular properties and protein crystallization propensity. Accounting for comprehensive biological mechanisms, our tool can facilitate the rational design of protein sequences that lead to diffraction-quality crystals. Our study showcases the integration of physics-based and machine learning models for structure and property prediction, expanding the classical paradigm of structural biology.

The advances in wearable and skin-integrated electronics bring new opportunities in virtual and augmented reality beyond traditional audiovisual modes, in which the haptic interface can be worn on the body to provide a more immersive virtual reality experience. Exploration of different materials and methods has greatly improved the precision and degrees of haptic sensations in skin electronics, enhancing the realism of tactile experiences for immersing in the virtual world. However, haptic technology based on skin electronics still faces numerous challenges, such as biocompatibility, functionality, and smart applications. This perspective provides insights on the applications of materials and designs in various haptic skin electronics and then outlines the challenges and prospects of existing haptic skin electronics. It begins with a brief review of the development of haptic devices, from early industrial applications to advanced wearable skin electronics. After that, we summarize the materials used in the haptic skin electronics from the perspectives of mechanical, electrical, thermal, and others. Finally, we discuss the challenges of existing haptic skin electronics and outlook on the potential implementation methods for overcoming these challenges to enhance the overall haptic experience in realizing haptic feeling.

Bioluminescent reporters are widely used in fundamental and preclinical biological research. However, light absorption and scattering by tissues interferes with precise mapping of bioluminescent sources in deep locations, such as the brain, where the skull significantly blocks optical signal transmission. This preview highlights an ingenious approach that employs a cellular near-field camera to convert optical signals into hemodynamic changes detectable by magnetic resonance imaging. This transformation overcomes the optical limitations of tissue penetration depth and enables more precise mapping of bioluminescence sources in the brain.

Due to their superior thermal stability, inorganic perovskites, especially CsPbI₃, possess great application prospects. However, non-radiative recombination energy dissipation caused by defect states has always been a technical bottleneck restricting the development of perovskite solar cells. Herein, graphdiyne (GDY), an sp-hybridized carbon framework, has been introduced to manipulate the CsPbI₃ perovskite crystal lattice. On the one hand, GDY serves as a Lewis base, thereby regulating the perovskite crystallization process and leading to high-quality thin film with low-defect state density. On the other hand, the GDY molecule at grain boundaries relieves the inevitable crystal lattice stress within the CsPbI₃ perovskite film caused by the high thermal annealing temperature. As a result, a record-high fill factor of 83.96% and an ultra-high open-circuit voltage of 1.191 V for β-phase CsPbI₃ perovskite solar cells are achieved simultaneously. This work provides a proficient methodology to manipulate the crystal lattice of inorganic perovskites toward high-performance photovoltaics.

Multifunctional metal-organic frameworks (MOFs) hold great potential in addressing challenges in energy storage devices by offering customizable guest-host interactions. Herein, we integrated Lewis acidic metal clusters (M = Zr⁴⁺, Hf⁴⁺, and Th⁴⁺) and redox-active Ni-bis(dithiolene) units (NiS₄) into a series of bifunctional MOFs, which serve as both cathodic and anodic host materials for lithium-sulfur (Li-S) batteries. Through systematic control experiments and density functional theory simulations, we elucidate the crucial roles of metal clusters and NiS₄ units in achieving efficient adsorption and rapid electrocatalytic conversion of polysulfides on the cathode and promoting uniform Li nucleation for enhanced cycling stability on the anode. Optimizing the MOF design resulted in advanced Li-S batteries, exhibiting remarkable capacity retention (81.5%) and an ultrahigh Coulombic efficiency (99.5%) after 800 cycles. This study highlights the potential of multifunctional MOFs in simultaneously overcoming the bottlenecks faced by the S cathode and Li anode.

Gas-phase heterogeneous catalysis, in the simplest terms, involves the reaction of gaseous molecules adsorbed on active sites embedded within the surface of a solid, called the catalyst, to form a product. These reactions have traditionally been driven by fossil-fuel heat, with an accompanying carbon footprint. Despite these shortcomings, this genre of catalysis remains the bedrock of the chemical and petrochemical industries, with a global annual revenue of around thirteen trillion dollars. Professor Geoffrey Ozin and his Solar Fuels Group at the University of Toronto, through a decade of striving to displace thermochemistry with a photochemistry alternative, are participating in the shift of research from the materials science underpinning gas-phase heterogeneous photocatalysts toward the photochemical engineering of energy and cost-efficient photocatalysts and photoreactors, hallmarks of sustainable solar chemical and fuel technology.