Impedance metasurfaces enable accurate regulation of acoustic fields. However, they can hardly supply a flexible response as such perfect operation is accompanied by stringent requirements on the design of unit cells. Actually, an arbitrary lossless and passive target impedance matrix requires the tuning of 3 independent real parameters. The set composed of a reflection phase, a transmission amplitude, and a transmission phase, enables the representation of an arbitrary impedance matrix, possibly possessing singular elements. In this paper, a mechanism of phase-amplitude-phase modulation (PAP modulation) is developed for the generic design of the unit cells of acoustic impedance metasurfaces. Adjustable acoustic impedance metasurfaces are further available under this framework. An impedance unit with 3 mobile parts is designed based on this idea. The assembled metasurface can handle different incidences for acoustic field manipulation at a given frequency. Beam steering and beam splitting are considered as demonstration examples and are verified by numerical simulation and experiment. PAP modulation enriches the design of acoustic impedance metasurfaces and extends the range of application of impedance theory.

Hydrogel microparticles have been proved to be curative to diabetic wounds. Current trends focus on the integration of bioactive matrix and their smart stimulus-responsive release to meet the complex demand of regeneration in diabetic wound. In this paper, we present novel stem cell exosome-encapsulated Chinese herb glycyrrhizic acid (GA) hydrogel microparticles for wound healing. The integrated GA endows the hydrogel microparticles with antibacterial properties, while the encapsulated exosomes impart them with pro-angiogenesis ability. In addition, as the black phosphorus is incorporated into these hybrid hydrogel microparticles, the release profile of GA and exosomes could be controllable under near-infrared irradiation due to the excellent photothermal effect of black phosphorus and the reversible phase transformation properties of GA. Based on these features, we have demonstrated that these microparticles can effectively kill bacteria, scavenge free radical, and promote angiogenesis from in vitro experiments. Besides, they could also markedly accelerate the wound healing process by down-regulating inflammation and promoting collagen deposition and angiogenesis in bacteria-infected in vivo diabetic wound. These results indicate that the proposed exosome-integrated GA hydrogel microparticles present great potential for clinical diabetic wound treatment.

Introduction: Brain age prediction using neuroimaging data and machine learning algorithms holds significant promise for gaining insights into the development of neurodegenerative diseases. The estimation of brain age may be influenced not only by the imaging modality but also by multidomain clinical factors. However, the degree to which various clinical factors in individuals are associated with brain structure, as well as the comprehensive relationship between these factors and brain aging, is not yet clear. Methods: In this study, multimodal brain magnetic resonance imaging data and longitudinal clinical information were collected from 964 participants in a population-based cohort with 16 years of follow-up in northern China. We developed a machine learning-based algorithm to predict multimodal brain age and compared the estimated brain age gap (BAG) differences among the 5 groups characterized by varying exposures to these high-risk clinical factors. We then estimated modality-specific brain age in the hypertension group based on hypertension-related regional imaging metrics. Results: The results revealed a significantly larger BAG estimated from multimodal neuroimaging in subjects with 4 or 5 risk factors compared to other groups, suggesting an acceleration of brain aging under cumulative exposure to multiple risk factors. The estimated T1-based BAG exhibited a significantly higher level in the hypertensive subjects compared to the normotensive individuals. Conclusion: Our study provides valuable insights into a range of health factors across lifestyle, metabolism, and social context that are reflective of brain aging and also contributes to the advancement of interventions and public health initiatives targeted at the general population aimed at promoting brain health.

Transmissive metasurfaces are essentially conducive to stealth, absorbers, and communications. However, most of the current schemes only allow microwave to transmit and generally adopt multilayer structures or thick dielectric substrates to improve the electromagnetic performance, restricting optical transmission and conformal application. In addition, most metasurfaces still require metal wires and external power suppliers for programmability. Here, we propose and design an intelligent transmissive microwave metasurface with optical sensing and transparency, which provides both microwave and optical channels without redundant optical devices and power suppliers, and the 2 transmission channels are associated with each other. The metasurface is realized by validly integrating photosensitive materials into microwave meta-structures. As a demonstration, we fabricate an ultrathin optically transparent transmissive metasurface based on polyethylene terephthalate substrate and photoresistors, whose thickness is only 0.125 mm. We further construct cross-wavelength transmission links based on the metasurface sample and experimentally validate that the microwave transmissions vary with light intensities under full-polarization and large-angle incidences, and this metasurface possesses high optical transparency. The intelligent transmissive microwave metasurface with optical sensing and transparency has potential applications in optical–microwave hybrid transmission devices and stealth technology.

Ion selectivity is a fundamental feature for designing advanced nanopores/channel systems, for example, biosensors or selectively permeable membranes. Comparison between different studies is a way to find and design the nanopore/membrane with pronounced selectivity. However, there is a huge hurdle in comparing the ion selectivities between studies, resulting from different equations from diverse scopes of science. Here, the authors from “Addressing challenges in ion-selectivity characterization in nanopores” emphasized the misinterpretation of the traditionally used Nernst and Goldman–Hodgkin–Katz equations in the previous literature and suggested the use of uniform criteria to overcome this ambiguity. We highlight the potential future applications of using uniform criteria in describing ion selectivity, which is beneficial to developing a massive AI-based databank. This databank would be advantageous for predicting and designing the ion selectivity of nanopores/nanomaterials in question for various applications in biological and material sciences.

Intervening in the microbial environment holds promise for enhancing antitumor efficacy by reshaping the tumor microenvironment, yet few strategies have been reported. In a study led by Zou and coworkers, oral hydrogels are introduced to regulate the microbiota balance in the intestines and tumors, triggering an antitumor immune response. This work presents a microbiota-targeted drug delivery system that demonstrates notable efficacy in colon targeting and colon retention for the treatment of colorectal cancer. This represents a significant clinical advancement in treating colorectal cancer, which is particularly vulnerable to microbial infiltration.

Psychedelics have long been recognized not only for their profound impact on human consciousness but also for their potential therapeutic applications. This perspective explores the multifaceted relationship between psychedelics and consciousness, emphasizing their capacity to alter sensory perceptions, disrupt self-referential thought processes, and catalyze profound spiritual and existential experiences. As research advances, psychedelics are being integrated into therapeutic settings, challenging existing psychiatric models and offering new insights into the complex nature of consciousness and mental health. This emerging paradigm marks the need for careful regulation and ethical considerations in the therapeutic use of psychedelics, promising a more holistic approach to mental health disorders.

This commentary underscores the importance and implications of the study “Biomolecular condensates with complex architectures via controlled nucleation,” led by Jan C. M. van Hest and Tuomas P. J. Knowles, published in Nature Chemical Engineering. The research team developed a novel system to investigate the structure of biological condensates using quaternized amylose, carboxymethylated amylose, and single-stranded DNA. They successfully created multiphase droplets with distinct dense phases and demonstrated that droplet architecture can be controlled through temperature and salt concentration adjustments. This study offers valuable insights into the formation and function of membraneless organelles in cells and suggests promising applications for designing biomimetic materials and therapeutic strategies.