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The early monitoring and inactivation of bacteria are of crucial importance in preventing the further spread of foodborne pathogens. Staphylococcus aureus (S. aureus), a prototypical foodborne pathogen, is widely present in the natural environment and has the capability to trigger a range of diseases at low concentrations. In this work, we designed Fe3O4@SiO2-Au core–shell–satellite nanocomposites (NCs) modified with aptamer for efficient capture, high-sensitivity surface-enhanced Raman scattering (SERS) detection, and photothermal therapy (PTT) against S. aureus. Fe3O4@SiO2-Au NCs with tunable Au nanocrystal nanogaps were prepared. By combining the finite-difference time-domain (FDTD) method and experimental results, we studied the electric field distribution of Fe3O4@SiO2-Au under different Au nanogaps and ultimately obtained the optimal SERS substrate FSA-60. The modification of aptamer on the surfaces of FSA-60 could be used for the specific capture and selective detection of S. aureus, achieving a detection limit of as low as 50 cfu/mL. Furthermore, Apt-FSA-60 possessed excellent photothermal properties, demonstrating the strong photothermal killing ability against S. aureus. Therefore, Apt-FSA-60 is a promising high-sensitivity SERS substrate and efficient photothermal agent and is expected to be widely applied and promoted in future disease prevention and treatment. [ABSTRACT FROM AUTHOR]

This document is an editorial for a special issue of the journal Micromachines on the methodology, microfabrication, and applications of advanced sensing and smart systems. The editorial highlights the increasing integration of sensing technology with other cutting-edge technologies, such as machine learning, wearable sensors, and the Internet of Things. The special issue includes articles on topics such as intelligent manufacturing methodologies, fluorescence microscopy image inpainting, MEMS micromirrors, wearable robotics, quantitative analysis of particle size, and medical monitoring systems. The authors express gratitude to the contributors and reviewers and hope that the articles will inspire new innovations in advanced sensing and smart systems. [Extracted from the article]

Unusual electrical transport properties associated with weak or strong localization are sometimes found in disordered electronic materials. Here, we report experimental observation of a crossover of electronic behavior from weak localization to enhanced weak localization due to the spatial influence of disorder induced by ZrO2 nanopillars in (La2/3Sr1/3MnO3)1−x:(ZrO2)x (x = 0, 0.2, and 0.3) nanocomposite films. The spatial strain regions, identified by scanning transmission electron microscopy and high-resolution x-ray diffraction, induce a coexistence of two-dimentional (2D) and three-dimentional (3D) localization and switches to typical 2D localization with increasing density of ZrO2 pillars due to length scale confinement, which interestingly accords with enhancing vertically interfacial strain. Based on the excellent agreement of our experimental results with one-parameter scaling theory of localization, the enhanced weak localization exists in metal range close to the fixed point. These films provide a tunable experimental model for studying localization in particular the transition regime by appropriate choice of the second epitaxial phase. [ABSTRACT FROM AUTHOR]

Rational control of local strain distributions and thus the functional properties of epitaxial thin films has been a long‐standing goal in the development of new physics and novel devices based on strain‐sensitive materials. Here, the fabrication of La2/3Sr1/3MnO3 (LSMO) films with strain fields arising from vertical epitaxial embedding of ultra‐small ZrO2 nanopillars, diameter 4.0 ± 0.6 nm, is reported. High quality films are obtained with average distance between adjacent nanopillars of 9.0 ± 0.3 nm for x = 0.2 in (LSMO)1−x:(ZrO2)x. The strain distribution of the vertical interface is analyzed in detail and the dominant state of the interfacial strain is verified. Remarkably, with increasing x, the Curie temperature TC and metal–insulator (MI) transition temperature TMI show a surprisingly large depression, revealing the significant tuning capability of the vertical tensile stress originating from the small‐size ZrO2 pillars. A systematic tunability of the low field magnetoresistance is also found. The field dependence of the magnetization exhibits both horizontal and vertical shifts. The exchange bias field HE increases with increasing x, while magnetization shift Mshift is unchanged. The results suggest the possibility of strain tuning through epitaxial nanostructures for multifunctional applications across many fields with appropriate selection of matrix and nanopillar materials. [ABSTRACT FROM AUTHOR]

The influence of anisotropic strains on coupling spins is systematically investigated in pulsed laser deposited single crystal Pr5/8Ca3/8MnO3 film. The substrate was chosen to introduce tensile and compressive strain onto the film. Various experiments, i.e., zero field cooled/field cooled (ZFC/FC) magnetization measurement, hysteresis loops, and exchange bias field detection, have revealed distinct difference along two perpendicular in-plane axes which represent tensile and compressive strain orientation, respectively. We found that the observed phenomenon can be explained by the external strain effect. [ABSTRACT FROM AUTHOR]

Abstract: We explore the low-temperature magnetotransport properties of La2/3Sr1/3MnO3 (LSMO) epitaxial films with nano-scaled non-magnetic ZrO2 precpitates and analyze the low-temperature resistance anomalies within the frame of precipitate-induced Quantum Interference Effects (QIE) and anisotropic magnetoresistance. Two competing mechanisms triggered by the ZrO2 nanoparticles, weak localization and magnetic domain pattern modifications, are proposed to govern the observed anomalous magnetic response at low and high magnetic fields, respectively. The occurrence of these anomalies in LSMO with non-magnetic ZrO2 clusters shines new light at defect-induced magnetoelastic coupling. [Copyright &y& Elsevier]

We report electronic transport measurements on high quality floating zone grown NaxCo02 and Nao.41Co02 · 0.6H2O single crystals. We find an in-plane electronic scattering minimum near UK and a clear charge ordering at approximately 50 K. The electronic and magnetic properties in hydrated and nonhydrated Nao.41Co02 samples are similar at higher temperature, but evolve in markedly different ways below ∼50 K, where a strong ferromagnetic tendency is observed in the hydrated sample. Model calculations show the relationship of this tendency to the structure of the Fermi surface. The results, particularly the clear differences between the hydrated and nonhydrated material show a substantially enhanced ferromagnetic tendency upon hydration. Implications for superconductivity are discussed [ABSTRACT FROM AUTHOR]

The design of mutifunctional protein films for large-area spatially ordered arrays of functional components holds great promise in the field of biomedical applications. Herein, interfacial electrostatic self-assembly was employed to construct a large-scale protein thin film by inducing electrostatic interactions between three bovine serum albumin (BSA)-coated nanoclusters and cetyltrimethylammonium bromide (CTAB), leading to their spontaneous organization and uniform distribution at the oil-water interface. This protein film demonstrated excellent multienzyme functions, high antibacterial activity, and pH-responsive drug release capability. Therefore, it can accelerate the wound closure process through a synergistic effect that includes reducing local blood glucose levels, regulating cellular oxidative stress, eradicating bacteria, and promoting cell proliferation.

Unusual electrical transport properties associated with weak or strong localization are sometimes found in disordered electronic materials. Here, we report experimental observation of a crossover of electronic behavior from weak localization to enhanced weak localization due to the spatial influence of disorder induced by ZrO 2 nanopillars in (La 2/3 Sr 1/3 MnO 3 ) 1-x :(ZrO 2 ) x (x = 0, 0.2, and 0.3) nanocomposite films. The spatial strain regions, identified by scanning transmission electron microscopy and high-resolution x-ray diffraction, induce a coexistence of two-dimentional (2D) and three-dimentional (3D) localization and switches to typical 2D localization with increasing density of ZrO 2 pillars due to length scale confinement, which interestingly accords with enhancing vertically interfacial strain. Based on the excellent agreement of our experimental results with one-parameter scaling theory of localization, the enhanced weak localization exists in metal range close to the fixed point. These films provide a tunable experimental model for studying localization in particular the transition regime by appropriate choice of the second epitaxial phase., (© 2023. The Author(s).)