The current single-atom catalysts (SACs) for medicine still suffer from the limited active site density. Here, we develop a synthetic method capable of increasing both the metal loading and mass-specific activity of SACs by exchanging zinc with iron. The constructed iron SACs (h³-FNC) with a high metal loading of 6.27 wt% and an optimized adjacent Fe distance of ~ 4 Å exhibit excellent oxidase-like catalytic performance without significant activity decay after being stored for six months and promising antibacterial effects. Attractively, a “density effect” has been found at a high-enough metal doping amount, at which individual active sites become close enough to interact with each other and alter the electronic structure, resulting in significantly boosted intrinsic activity of single-atomic iron sites in h³-FNCs by 2.3 times compared to low- and medium-loading SACs. Consequently, the overall catalytic activity of h³-FNC is highly improved, with mass activity and metal mass-specific activity that are, respectively, 66 and 315 times higher than those of commercial Pt/C. In addition, h³-FNCs demonstrate efficiently enhanced capability in catalyzing oxygen reduction into superoxide anion (O₂·⁻) and glutathione (GSH) depletion. Both in vitro and in vivo assays demonstrate the superior antibacterial efficacy of h³-FNCs in promoting wound healing. This work presents an intriguing activity-enhancement effect in catalysts and exhibits impressive therapeutic efficacy in combating bacterial infections.

Defects-rich heterointerfaces integrated with adjustable crystalline phases and atom vacancies, as well as veiled dielectric-responsive character, are instrumental in electromagnetic dissipation. Conventional methods, however, constrain their delicate constructions. Herein, an innovative alternative is proposed: carrageenan-assistant cations-regulated (CACR) strategy, which induces a series of sulfides nanoparticles rooted in situ on the surface of carbon matrix. This unique configuration originates from strategic vacancy formation energy of sulfides and strong sulfides-carbon support interaction, benefiting the delicate construction of defects-rich heterostructures in M_xS_y/carbon composites (M-CAs). Impressively, these generated sulfur vacancies are firstly found to strengthen electron accumulation/consumption ability at heterointerfaces and, simultaneously, induct local asymmetry of electronic structure to evoke large dipole moment, ultimately leading to polarization coupling, i.e., defect-type interfacial polarization. Such “Janus effect” (Janus effect means versatility, as in the Greek two-headed Janus) of interfacial sulfur vacancies is intuitively confirmed by both theoretical and experimental investigations for the first time. Consequently, the sulfur vacancies-rich heterostructured Co/Ni-CAs displays broad absorption bandwidth of 6.76 GHz at only 1.8 mm, compared to sulfur vacancies-free CAs without any dielectric response. Harnessing defects-rich heterostructures, this one-pot CACR strategy may steer the design and development of advanced nanomaterials, boosting functionality across diverse application domains beyond electromagnetic response.

Metasurfaces are formed by engineering a glass surface with an array of microscopic features, or meta-atoms. Although different optical functionalities can be obtained by changing only the pattern, the resulting metasurfaces often lack the necessary efficiency for many applications. In this report, scientists from Corning and Harvard University collaborate to demonstrate an inverse-design method that optimizes efficiency while respecting fabrication constraints. These results represent a step forward in making practical metasurfaces for broader applications.

A research team has leveraged cutting-edge noninvasive phenotyping technologies to monitor plant stress across multiple vegetative organs.

A research team reveals how a low-cost imaging phenotyping system successfully uncovers the mechanisms of quantitative disease resistance (QDR) in wild tomato species.

Early development of an embryo is solely supported by maternally deposited RNAs and proteins until its own genome is activated through a process called zygotic genome activation (ZGA). Recent research by Chinese scientists has revealed novel molecular mechanisms by which HIRA acts in concert with dPCIF1 to establish a totipotent chromatin and facilitate orderly zygotic genome activation in the early embryos of Drosophila.

This study suggests that GERD may elevate cardiovascular risks, including increased blood pressure, unhealthy lipid levels, and a higher likelihood of heart disease. Through advanced genetic analysis, researchers linked GERD to elevated systolic and diastolic blood pressure, higher LDL cholesterol, and an increased risk of heart attack, highlighting GERD’s broader health implications.

Machine learning's predictive power is underutilized in vehicle-pedestrian risk identification, impeding proactive safety. A new model is needed to estimate crash severity, not just frequency. Researchers propose a novel framework combining machine learning and extreme value theory to estimate pedestrian crash frequencies by injury severity levels.

Researchers at the University of Natural Resources and Life Sciences, Vienna, and Institut Teknologi Sumatera, Indonesia, set out to explore the dynamics behind shared micromobility fleet development. By utilizing a system dynamics modeling approach, they examined how fleet size, user demand, regulatory policies, and economic factors interact to shape the success of these systems.

Researchers delved deep into the regulation of cobalt active sites to enhance the selectivity of propylene to improve scalability and affordability of the production of this important chemical.