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The quantum anomalous Hall effect (QAHE) enables dissipation-free motion within its edge states, offering considerable potential for developments in the fields of electronics, phononics, and elastic waves. In this study, we introduce an elastic metamaterial designed to realize the QAHE at low frequencies. Our approach involves deploying a two-dimensional honeycomb spring-mass system on a rotating platform to break time-reversal symmetry via the Coriolis Force and incorporating local resonators to achieve low-frequency topological edge states. We begin by deriving the system's equations of motion through analytical rigid body dynamics. Subsequently, we apply Bloch wave solutions to establish the dispersion relations and identify the topological edge states. We then conduct numerical simulations to confirm the one-way transmission characteristics of these states. The addition of local resonators not only extends the frequency range of the topological edge states but also lowers the operational frequency of the system. This robust waveguide, capable of one-way transmission, has potential applications in directional transmission, vibration damping, noise reduction, and acoustic imaging. [ABSTRACT FROM AUTHOR]

In this study, we propose a coaxial composite resonator (CCR) structural unit and experimentally demonstrate that a periodic structural plate composed of CCR units effectively suppresses low-frequency vibrations. Each CCR unit comprises a cylindrical resonant element, a steering wheel-shaped elastic connection, and a framework structure. These components collectively generate elastic wave bandgaps through the intrinsic damping properties of the resonant elements. Finite element analysis was employed to investigate the influence of key parameters on the bandgap (BG) characteristics of the CCR structure. The results indicate that the resonator mass is the primary determinant of the BG onset frequency, with larger resonator masses leading to a lower onset frequency. Additionally, the lattice constant was identified as the most sensitive parameter influencing the BG width, such that an increased lattice constant results in an expanded frequency range of the BG. The validity of the finite element models and the predicted BG properties were confirmed through experimental testing. The CCR structure exhibits significant potential for applications in low-frequency vibration and noise control. [ABSTRACT FROM AUTHOR]

Efferocytosis refers to the process by which phagocytes remove apoptotic cells and related apoptotic products. It is essential for the growth and development of the body, the repair of damaged or inflamed tissues, and the balance of the immune system. Damaged efferocytosis will cause a variety of chronic inflammation and immune system diseases. Many studies show that efferocytosis is a process mediated by mitochondria. Mitochondrial metabolism, mitochondrial dynamics, and communication between mitochondria and other organelles can all affect phagocytes' clearance of apoptotic cells. Therefore, targeting mitochondria to modulate phagocyte efferocytosis is an anticipated strategy to prevent and treat chronic inflammatory diseases and autoimmune diseases. In this review, we introduced the mechanism of efferocytosis and the pivoted role of mitochondria in efferocytosis. In addition, we focused on the therapeutic implication of drugs targeting mitochondria in diseases related to efferocytosis dysfunction. [ABSTRACT FROM AUTHOR]

To elucidate the nonlinear oscillations inherent to dielectric elastomer transducers (DETs), this study delves into the dynamic behaviour exhibited by a one-dimensional asymmetric Duffing oscillator, which may exhibit either hardening or softening stiffness. The investigation utilizes hyperelastic and visco-hyperelastic constitutive models to capture the nonlinear stiffness properties of dielectric elastomers within compliant transducers. The canonical Duffing equation is employed to articulate the oscillator's motion, complemented by both asymptotic and quantitative analyses of unforced vibrations and harmonic excitation. Our results reveal that the distinctive stiffness characteristics observed in DETs arise from the complex interplay among hyperelasticity, rheology and applied electric fields. Contrary to conventional oscillators, Maxwell stress substantially modifies the nonlinear dynamics of DETs, an aspect that has been quantitatively dissected in this study. Furthermore, the influence of additional system parameters on forced oscillation has also been meticulously evaluated. [ABSTRACT FROM AUTHOR]

The supramolecular lead iodide perovskite crystals, {[NH4(18-crown-6)]PbI3}∞ (1), (18-crown-6 = 1,4,7,10,13,16-hexaoxacyclooctadecane), was successfully achieved by a facile solvent evaporation strategy using a DMF solution containing equal molar quantities of PbI2, NH4I and 18-crown-6. The supramolecular perovskite was characterized by microanalysis for C, H and N elements, thermogravimetric (TG) analysis, differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and single crystal X-ray diffraction techniques. DSC measurements demonstrated that 1 experiences a two-step thermotropic phase transition around 333 K and 383 K, respectively. The phase transition is relevant to the disorder–order transformation of the 18-crown-6 molecule at ∼333 K, while both breaking-symmetry and ordered-disordered transformation of the 18-crown-6 molecule occurred at ∼383 K. In addition, the sharp change of the PbI6 coordination octahedron distortion degree plays a synergistic role in the two-step phase transition. The dielectric relaxation occurs above 243 K in 1 and is mainly attributed to the displacement of the NH4+ ions relative to the ring of the 18-crown-6 molecule and {PbI3}∞ chain induced by an AC electrical field. [ABSTRACT FROM AUTHOR]

The supramolecular lead iodide perovskite crystals, {[NH4(18-crown-6)]PbI3}∞ (1), (18-crown-6 = 1,4,7,10,13,16-hexaoxacyclooctadecane), was successfully achieved by a facile solvent evaporation strategy using a DMF solution containing equal molar quantities of PbI2, NH4I and 18-crown-6. The supramolecular perovskite was characterized by microanalysis for C, H and N elements, thermogravimetric (TG) analysis, differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and single crystal X-ray diffraction techniques. DSC measurements demonstrated that 1 experiences a two-step thermotropic phase transition around 333 K and 383 K, respectively. The phase transition is relevant to the disorder–order transformation of the 18-crown-6 molecule at ∼333 K, while both breaking-symmetry and ordered-disordered transformation of the 18-crown-6 molecule occurred at ∼383 K. In addition, the sharp change of the PbI6 coordination octahedron distortion degree plays a synergistic role in the two-step phase transition. The dielectric relaxation occurs above 243 K in 1 and is mainly attributed to the displacement of the NH4+ ions relative to the ring of the 18-crown-6 molecule and {PbI3}∞ chain induced by an AC electrical field. [ABSTRACT FROM AUTHOR]

Metal—organic chemical vapor deposition (MOCVD) grown ferromagnetic GaMnN films are investigated by photoluminescence (PL) measurement with a mid-gap excitation wavelength of 405 nm. A sharp PL peak at 1.8 eV is found and the PL intensity successively decreases with the addition of Mn, in which the Mn concentration of sample A is below 1% ([Mn]A = 0.75%) but its PL intensity is stronger than other samples'. The 1.8-eV PL peak is attributed to the recombination of electrons in the t2 state of the neutral Mn3+ acceptor with holes in the valence band. With Mn concentration increasing, the intensity of the PL peak decreases and the magnetic increment reduces in our samples. The correlation between the PL peak intensity and ferromagnetism of the samples is discussed in combination with the experimental results. [ABSTRACT FROM AUTHOR]

Ischemia-reperfusion injury is a complex hemodynamic pathology that is a leading cause of death worldwide and occurs in many body organs. Numerous studies have shown that mitochondria play an important role in the occurrence mechanism of ischemia-reperfusion injury and that mitochondrial structural abnormalities and dysfunction lead to the disruption of the homeostasis of the whole mitochondria. At this time, mitochondria are not just sub-organelles to produce ATP but also important targets for regulating ischemia-reperfusion injury; therefore, drugs targeting mitochondria can serve as a new strategy to treat ischemia-reperfusion injury. Based on this view, in this review, we discuss potential therapeutic agents for both mitochondrial structural abnormalities and mitochondrial dysfunction, highlighting the application and prospects of targeted mitochondrial drugs in the treatment of ischemia-reperfusion injury, and try to provide new ideas for the clinical treatment of the ischemia-reperfusion injury., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Objective: To determine the effect of downregulation of 53BP1 expression on cell growth and radiosensitivity in laryngeal carcinoma Hep-2 cells., Methods: HEP-2 cell lines were established with a stable knockdown of 53BP1 with short hairpin RNA (shRNA). The level of expressed protein of negative control group (NC),wild type Hep-2 and downregulation of 53BP1 (P6) group was determined by Western blotting. Proliferation on normal conditions was detected by MTT. Radiosensitivity and growth of cells were detected by flow cytometry., Results: A stable 53BP1 downregulated cell line P6 was established. Similar cell growth was observed between the 53BP1 downregulated cells and the control cells. The downregulation of 53BP1 reduced the number of clonogenic cells exposed to radiation. Compared with wild type Hep-2 group and NC group, Western blot results showed a decrease in 53BP1 protein level in P6 group (P < 0.05), reducing the ratio of arrest of G2/M with radiation dose increased (P < 0.05). MTT results revealed the lower 53BP1 protein level did not affect the cell proliferation. After exposure to 0, 2, 6, 10 Gy ionizing radiation (IR), P6 cells had lower, radiosensitivity parameters (D0, SF2, Dq, N) than controls and wild type Hep-2 (P < 0.05)., Conclusion: RNA interference could effectively down-regulate the expression of 53BP1 and reduce arrest of G2/M phase, thus enhancing the radiosensitivity of Hep-2 cell line.