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Background: Temporal interference (TI) stimulation, an innovative non-invasive brain stimulation approach, has the potential to activate neurons in deep brain regions. However, the dynamic mechanisms underlying its neuromodulatory effects are not fully understood. This study aims to investigate the effects of TI stimulation on dynamic functional connectivity (dFC) in the motor cortex. Methods: 40 healthy adults underwent both TI and tDCS in a double-blind, randomized crossover design, with sessions separated by at least 48 h. The total stimulation intensity of TI is 4 mA, with each channel's intensity set at 2 mA and a 20 Hz frequency difference (2 kHz and 2.02 kHz). The tDCS stimulation intensity is 2 mA. Resting-state functional magnetic resonance imaging (rs-fMRI) data were collected before, during, and after stimulation. dFC was calculated using the left primary motor cortex (M1) as the region of interest (ROI) and analyzed using a sliding time-window method. A two-way repeated measures ANOVA (group × time) was conducted to evaluate the effects of TI and tDCS on changes in dFC. Results: For CV of dFC, significant main effects of stimulation type (P = 0.004) and time (P < 0.001) were observed. TI showed lower CV of dFC than tDCS in the left postcentral gyrus (P < 0.001). TI-T2 displayed lower CV of dFC than TI-T1 in the left precentral gyrus (P < 0.001). For mean dFC, a significant main effect of time was found (P < 0.001). TI–T2 showed higher mean dFC than tDCS-T2 in the left postcentral gyrus (P = 0.018). Within-group comparisons revealed significant differences between time points in both TI and tDCS groups, primarily in the left precentral and postcentral gyri (all P < 0.001). Results were consistent across different window sizes. Conclusion: 20 Hz TI stimulation altered dFC in the primary motor cortex, leading to a significant decreasing variability and increasing mean connectivity strength in dFC. This outcome indicates that the 20 Hz TI frequency interacted with the motor cortex's natural resonance. [ABSTRACT FROM AUTHOR]

Mild‐heat photothermal antibacterial therapy avoids heat‐induced damage to normal tissues but causes bacterial tolerance. The use of photothermal therapy in synergy with chemodynamic therapy is expected to address this issue. Herein, two pseudo‐conjugated polymers PM123 with photothermal units and PFc with ferrocene (Fc) units are designed to co‐assemble with DSPE‐mPEG2000 into nanoparticle NPM123/Fc. NPM123/Fc under 1064 nm laser irradiation (NPM123/Fc+NIR‐II) generates mild heat and additionally more toxic ∙OH from endogenous H2O2, displaying a strong synergistic photothermal and chemodynamic effect. NPM123/Fc+NIR‐II gives >90% inhibition rates against MDR ESKAPE pathogens in vitro. Metabolomics analysis unveils that NPM123/Fc+NIR‐II induces bacterial metabolic dysregulation including inhibited nucleic acid synthesis, disordered energy metabolism, enhanced oxidative stress, and elevated DNA damage. Further, NPM123/Fc+NIR‐II possesses >90% bacteriostatic rates at infected wounds in mice, resulting in almost full recovery of infected wounds. Immunodetection and transcriptomics assays disclose that the therapeutic effect is mainly dependent on the inhibition of inflammatory reactions and the promotion of wound healing. What is more, thioketal bonds in NPM123/Fc are susceptible to ROS, making it degradable with highly favorable biosafety in vitro and in vivo. NPM123/Fc+NIR‐II with a unique synergistic antibacterial strategy would be much less prone to select bacterial resistance and represent a promising antibiotics‐alternative anti‐infective measure. [ABSTRACT FROM AUTHOR]

Abstract Electrical transport properties of individual metallic double-walled carbon nanotubes (DWCNTs) were measured down to liquid helium temperature, and multi-stable conductance states were found in DWCNTs. At a certain temperature, DWCNTs can switch continuously between two or more electronic states, but below certain temperature, DWCNTs are stable only at one of them. The temperature for switching is always different from tube to tube, and even different from thermal cycle to cycle for the same tube. In addition to thermal activation, gate voltage scanning can also realize such switching among different electronic states. The multi-stable conductance states in metallic DWCNTs can be attributed to different Fermi level or occasional scattering centers induced by different configurations between their inner and outer tubes.