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Kidney transplantation is the best therapy for end‐stage renal disease. Demand for kidney transplantation rises year‐on‐year, and the gap between kidney supply and demand remains large. To meet this clinical need, a gradual expansion in the supply of donors is required. However, clinics lack appropriate tools capable of quickly and accurately predicting post‐transplant renal allograft function, and thus assess donor‐kidney quality before transplantation. Mitochondrial DNA (mtDNA) is a key component of damage‐associated molecular patterns (DAMPs) and plays an important part in ischemia‐reperfusion injury (IRI), accelerating the progression of IRI by inducing inflammation and type I interferon responses. mtDNA is known to be closely involved in delayed graft function (DGF) and acute kidney injury (AKI) after transplantation. Thus, mtDNA is a potential biomarker able to predict post‐transplant renal allograft function. This review summarizes mtDNA biology, the role mtDNA plays in renal transplantation, outlines advances in detecting mtDNA, and details mtDNA's able to predict post‐transplant renal allograft function. We aim to elucidate the potential value of mtDNA as a biomarker in the prediction of IRI, and eventually provide help for predicting donor‐kidney quality. [ABSTRACT FROM AUTHOR]

The local electron density of an atom is one key factor that determines its chemical properties. Regulating electron density can promote the atom's reactivity and so reduce the reaction activation energy, which is highly desired in many chemical applications. Herein, we report an intra‐crystalline electron lever strategy, which can regulate the electron density of reaction centre atoms via manipulating ambient lattice states, for Fenton activity improvement. Typically, with the assistance of ultrasound, the Mn4+−O−Fe3+ bond in BiFe0.97Mn0.03O3 perovskite nanocrystals can drive valence electrons and free electrons to accumulate on Fe atoms by a polarization electric field originated from the designed lattice strain. The increase of electron density significantly improves the catalytic activity of Fe, decreasing the activation energy of BiFe0.97Mn0.03O3‐mediated Fenton reaction by 52.55 %, and increasing the.OH yield by 9.21‐fold. This study provides a new way to understand the sono‐Fenton chemistry, and the increased.OH production enables a highly effective chemodynamic therapy. [ABSTRACT FROM AUTHOR]

Aurivillius phase Ca2Bi4Ti5O18 powders with micrometer size were produced by solid‐state reaction. X‐ray diffraction revealed that the powders had polar orthorhombic structure with space group of B2cb. Ca2Bi4Ti5O18 ceramic exhibited frequency independent dielectric anomaly at 774°C. The piezoelectric coefficient d33 value of poled Ca2Bi4Ti5O18 pellets was 0.7 ± 0.2 pC/N. Both frequency independent dielectric anomaly and detectable d33 value clearly indicated that Ca2Bi4Ti5O18 is a ferroelectric material with Curie point of 774 ℃. UV–vis absorption spectra revealed that Ca2Bi4Ti5O18 had a direct band gap of 3.2 eV. Photocatalytic activity of the Ca2Bi4Ti5O18 powders was examined by degradation of rhodamine B (RhB) under simulated solar light. 16% of RhB solution was degraded by Ca2Bi4Ti5O18 powders after 4 hours UV‐vis irradiation. With Ag nanoparticles deposited on the Ca2Bi4Ti5O18 powders surface, 50% of RhB was degraded under the same irradiation condition. The fitted degradation rate constant of Ag decorated Ca2Bi4Ti5O18 was 4 times higher than that of bare Ca2Bi4Ti5O18. This work suggested that the Aurivillius ferroelectric Ca2Bi4Ti5O18 is a promising candidate for photocatalytic applications. [ABSTRACT FROM AUTHOR]

Electric‐field‐induced phase transitions in Bi0.5Na0.5TiO3‐based relaxor ferroelectrics are essential to the control of their electrical properties and consequently in revolutionizing their dielectric and piezoelectric applications. However, fundamental understanding of these transitions is a long‐standing challenge due to their complex crystal structures. Given the structural inhomogeneity at the nanoscale or sub‐nanoscale in these materials, dielectric response characterization based on terahertz (THz) electromagnetic‐probe beam fields is intrinsically coordinated to lattice dynamics during DC‐biased poling cycles. The complex permittivity reveals the field‐induced phase transitions to be irreversible. This profoundly counters the claim of reversibility, the conventional support for which is based upon the peak that is manifest in each of four quadrants of the current–field curves. The mechanism of this irreversibility is solely attributed to polar clusters in the transformed lattices. These represent an extrinsic factor, which is quiescent in the THz spectral domain. [ABSTRACT FROM AUTHOR]

Lead‐free Aurivillius phase BaBi2Nb2O9 powders were prepared by solid‐state reaction. Ferroelectric measurements on BaBi2Nb2O9 (BBNO) ceramics at room temperature provided supporting evidence for the existence of polar nanoregions (PNRs) and their reversible response to an external electric field, indicating relaxor behavior. The photocatalytic degradation of Rhodamine B reached 12% after 3 hours irradiation of BBNO powders under simulated solar light. Silver (Ag) nanoparticles were photochemically deposited onto the surface of the BBNO powders and found to act as electron traps, facilitating the separation of photoexcited charge carriers; thus, the photocatalytic performance was significantly improved. The present study is the first examination of the photochemical reactivity of a relaxor ferroelectric within the Aurivillius family with PNRs. [ABSTRACT FROM AUTHOR]

In article number 1901373, J Wu, B Yang, D Zhang, H Yan and co‐workers demonstrate the importance of terahertz (THz) technology in decoding the intrinsic structural dynamics of Bi0.5Na0.5TiO3‐based ferroelectrics. During DC‐field poling cycles, the variated dielectric response probed by reflected‐THz beam is coordinated to the permanent change of polar clusters. The evolution of perovskite unit cells symbolizes the irreversible field‐induced structural changes at the lattice scale. [ABSTRACT FROM AUTHOR]

Aurivillius phase Ca2Bi4Ti5O18 powders with micrometer size were produced by solid‐state reaction. X‐ray diffraction revealed that the powders had polar orthorhombic structure with space group of B2cb. Ca2Bi4Ti5O18 ceramic exhibited frequency independent dielectric anomaly at 774°C. The piezoelectric coefficient d33 value of poled Ca2Bi4Ti5O18 pellets was 0.7 ± 0.2 pC/N. Both frequency independent dielectric anomaly and detectable d33 value clearly indicated that Ca2Bi4Ti5O18 is a ferroelectric material with Curie point of 774 ℃. UV–vis absorption spectra revealed that Ca2Bi4Ti5O18 had a direct band gap of 3.2 eV. Photocatalytic activity of the Ca2Bi4Ti5O18 powders was examined by degradation of rhodamine B (RhB) under simulated solar light. 16% of RhB solution was degraded by Ca2Bi4Ti5O18 powders after 4 hours UV‐vis irradiation. With Ag nanoparticles deposited on the Ca2Bi4Ti5O18 powders surface, 50% of RhB was degraded under the same irradiation condition. The fitted degradation rate constant of Ag decorated Ca2Bi4Ti5O18 was 4 times higher than that of bare Ca2Bi4Ti5O18. This work suggested that the Aurivillius ferroelectric Ca2Bi4Ti5O18 is a promising candidate for photocatalytic applications. [ABSTRACT FROM AUTHOR]

Lead‐free Aurivillius phase BaBi2Nb2O9 powders were prepared by solid‐state reaction. Ferroelectric measurements on BaBi2Nb2O9 (BBNO) ceramics at room temperature provided supporting evidence for the existence of polar nanoregions (PNRs) and their reversible response to an external electric field, indicating relaxor behavior. The photocatalytic degradation of Rhodamine B reached 12% after 3 hours irradiation of BBNO powders under simulated solar light. Silver (Ag) nanoparticles were photochemically deposited onto the surface of the BBNO powders and found to act as electron traps, facilitating the separation of photoexcited charge carriers; thus, the photocatalytic performance was significantly improved. The present study is the first examination of the photochemical reactivity of a relaxor ferroelectric within the Aurivillius family with PNRs. [ABSTRACT FROM AUTHOR]