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Dielectric capacitors are very attractive for high power energy storage. However, the low energy density of these capacitors, which is mainly limited by the dielectric materials, is still the bottleneck for their applications. In this work, lead-free single-phase perovskite Sr x (Bi 1−x Na 0.97−x Li 0.03 ) 0.5 TiO 3 (x = 0.30 and 0.38) bulk ceramics, prepared using solid-state reaction method, were carefully studied for the dielectric capacitor application. Polar nano regions (PNRs) were created in this material using co-substitution at A-site to enable relaxor behaviour with low remnant polarization ( P r ) and high maximum polarization ( P max ). Moreover, P max was further increased due to the electric field induced reversible phase transitions in nano regions. Comprehensive structural and electrical studies were performed to confirm the PNRs and reversible phase transitions. And finally a high energy density (1.70 J/cm 3 ) with an excellent efficiency (87.2%) was achieved using the contribution of field-induced rotations of PNRs and PNR-related reversible transitions in this material, making it among the best performing lead-free dielectric ceramic bulk material for high energy storage. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide. The discovery and research of effective biomarkers have become prevailing trends. SUMO-activating enzyme subunit 1 (sae1), an E1-activating enzyme, is indispensable for protein SUMOylation. In this study, we conducted a comprehensive analysis of database contents and found that sae1 is highly expressed in HCC and is correlated with poor prognosis. We also identified its regulated transcription factor, rad51 , and related signaling pathways. We conclude that sae1 is a promising cancer metabolic biomarker with diagnostic and prognostic value in HCC. [ABSTRACT FROM AUTHOR]

• The assumption that He does not adsorb in porous media is not correct for Shales. • New method presented to measure the adsorption of shale-gas components in Shales. • The technique does not require He to measure the solid's skeletal volume. • A new zero-point correction method presented for the magnetic suspension balance, Measuring the adsorption of gases in microporous solids like the shales requires accurate knowledge of the solid's skeletal volume. Helium (He) is commonly used to determine the sample's skeletal volume based on the assumption that it does not adsorb in these porous media. The validity of such an assumption for microporous solids has been questioned in recent years, and in this study, we show that it is not applicable for the shale we study. We present a new method to measure the adsorption of shale-gas components in shales, which does not require the use of He to measure the solid's skeletal volume. Since the proposed analysis method relies on the use of dynamic adsorption data, we also propose here a new zero-point correction method for the magnetic suspension balance, which is better suited for the analysis of such data. We employ the new technique to the study of Argon adsorption in Marcellus shales. [ABSTRACT FROM AUTHOR]

There has been recently a great progress in the development of dielectric capacitors for high temperature electronic applications. The design of lead-free ceramics with high dielectric permittivity, low dielectric loss and a limited variation of these parameters over a wide temperature range is still a big challenge. In this work, lead-free Bi 0.35 Na 0.65 – 0.5x Rb 0.5x Ti 0.7 Nb 0.3 O 3 (x = 0–0.05) bulk ceramics were prepared using the solid-state reaction method. Upon Rb substitution, the variation of the dielectric permittivity was reduced substantially, in particular, at high temperature (over 200 °C). In addition, a low temperature coefficient of capacitance (TCC ≤ 10%) together with an ultra-low dielectric loss (tan δ ≤ 0.05) were achieved for the Bi 0.35 Na 0.63 Rb 0.02 Ti 0.7 Nb 0.3 O 3 sample in the temperature range from −43 °C to 292 °C. The new relaxor-type ferroelectrics also possess the outstanding stability of the dielectric properties under high DC bias voltage, which makes them promising materials for high-performance capacitors of the next generation. Unlabelled Image • Rb/Nb co-substituted Bi 0.5 Na 0.5 TiO 3 –based ceramics display TCC < 10% in the temperature range of −43 °C–292 °C. • The BNT-derived relaxors exhibit high permittivity (>800) and ultra-low dielectric loss (≤0.05) from −43 °C up to 292 °C. • The variance of the capacitance of the Bi 0.5 Na 0.5 TiO 3 –based ceramics is lower than 150 ppm under the DC voltage of 1 kV. [ABSTRACT FROM AUTHOR]

Kidney transplantation is the preferred treatment for patients with end-stage renal disease. However, various types of kidney graft injury after transplantation are still key factors that affect the survival of the kidney graft. Therefore, exploring the underlying mechanisms involved is very important. Current diagnostic measures for kidney graft injury (including needle biopsy, blood creatinine, eGFR, etc.) have many limiting factors such as invasiveness, insufficient sensitivity and specificity, so they cannot provide timely and effective information to clinicians. As for kidney grafts that have occurred injury, the traditional treatment has a little efficacy and many side effects. Therefore, there is an urgent need for developing new biomarkers and targeted treatment for kidney graft injury. Recently, studies have found that miRNAs are involved in the regulation of the progression of kidney graft injury. At the same time, it has high stability in blood, urine, and other body fluids, so it is suggested to have the potential as a biomarker and therapeutic target for kidney graft injury. Here, we reviewed the miRNAs involved in the pathophysiology of kidney graft injury such as ischemia/reperfusion injury, acute rejection, drug-induced nephrotoxicity, chronic allograft dysfunction, BK virus infection, and the latest advances of miRNAs as biomarkers and therapeutic targets of kidney graft injury, then summarized the specific data of miRNAs expression level in kidney graft injury, which aims to provide a reference for subsequent basic research and clinical transformation. • Discussing the advances of miRNAs on the mechanism, biomarkers, and therapeutic targets of kidney graft injury. • Summarizing the specific data of miRNAs expression level in kidney graft injury. • MiRNAs can be used as a novel biomarker or therapeutic target for the diagnosis and treatment of kidney graft injury in the future. [ABSTRACT FROM AUTHOR]

Due to the worldwide concerns of environmental protection and sustainable development, lead-free piezoelectric materials are greatly desired for bridging the electrical energy to the mechanical energy. However, their lower energy conversion coefficient compared to the conventional lead-containing piezoelectric materials significantly limits their device applications. Herein, we introduce a novel strategy to increase the strain of lead-free ferroelectric system via material structure design to create polar nano regions (PNRs) and point defects in the material while retaining the global ferroelectric phase. This added short-range structural heterogeneity in the material will facilitate the field-induced phase transition and reversible domain wall switching to enhance the strain. Following this strategy, we demonstrate an ultrahigh strain induced by an electric field in non-textured lead-free Bi 0.5 Na 0.5 TiO 3 (BNT)-based ceramics. The strain in unipolar mode (S uni) can reach up to 0.74% at 70 kV/cm, making it the highest value in reported lead-free ceramics so far. This puts forward a good route to design high-performance piezoelectric materials by material structure engineering. It also reveals the promising potential of lead-free piezoelectric materials in practical electromechanical device applications. Image 1 • The highest value of electro-strain (0.74%) is obtained in the lead-free ceramics. • Electro-strain is facilitated by the nanoscale structural heterogeneity. • Point defects are introduced to further enhance the strain value. [ABSTRACT FROM AUTHOR]

High power dielectric capacitors with high energy density are needed in order to develop modern electronic and electrical systems, including hybrid vehicles, telecommunication infrastructures and portable electronic devices. Relaxor ferroelectric polymers (RFP) are considered to be the most promising candidates for the next generation of capacitors owing to their relatively high energy storage density. However, the commercialization of RFP capacitors in power systems is hindered by their high cost and low dielectric breakdown strength. In this study, inexpensive, free-standing nano-crystalline (~3.3 nm) poly (vinylidene fluoride) (PVDF) films with high β phase content (~98%), "relaxor-like" ferroelectric behaviour and high breakdown strength (880 kV/mm) were fabricated using the facile Press & Folding (P&F) technique. An internal stress dominated polarization switching model is proposed to explain the origin of the relaxor-like ferroelectric behaviour. The internal stress generated during pressing alters the intermolecular chain distance of the (200) plane of β -PVDF from 4.24 Å in internal stress free films to 4.54 Å in P&F films, corresponding to a tensile strain and residual stress of 7.11% and 142 MPa, respectively. The internal stress acts to partially reverse the polarization on reversal of the applied electric field. This, combined with preferred in-plane orientation of the crystallites, results in a polar nanostructure with high polarization reversibility at high electric fields. A giant discharged energy storage density of 39.8 J/cm3 at 880 kV/mm was achieved for P&F films, which surpasses all previously reported polymer-based materials. Image 1 • Low-cost, free-standing, relaxor-like ferroelectric PVDF films prepared using a facile press-fold approach. • >98% fraction of polar β -phase with nano-crystallite size of ~3 nm. • An internal stress dominated polarization switching model is proposed to explain the relaxor-like ferroelectric behaviour. • Highest polarization reversibility is observed in the PVDF film with highest internal stress (~142 MPa). • A giant discharged energy density of 39.8 J/cm3 at 880 kV/mm. [ABSTRACT FROM AUTHOR]

Abstract Highly textured Ba 2 Bi 4 Ti 5 O 18 ceramic was prepared by spark plasma sintering (SPS). X-ray diffraction of the ceramics revealed the coexistence of a major ferroelectric phase (Space group, SG: B 2 cb) and a minor paraelectric phase (SG: I4/mmm) at room temperature. A diffused phase transition was observed at around 240 °C. The evolution of the switching current peaks in the electric current vs. electric field (I-E) loops with increasing temperature was interpreted by the structural changes and temperature dependent polarisation reversal processes. The slim polarisation vs. electric field (P-E) loops, the extra switching current peaks in the I-E loops and the non-zero piezoelectric d 33 coefficient indicate that Ba 2 Bi 4 Ti 5 O 18 is a relaxor ferroelectric material. The recoverable energy density (0.41 ± 0.01 J/cm3) of Ba 2 Bi 4 Ti 5 O 18 ceramics in the perpendicular direction to the SPS pressing direction is close to that of Pb(Mg 1/3 Nb 2/3)O 3 -based ceramics. The obtained results suggest Ba 2 Bi 4 Ti 5 O 18 ceramics might be promising for energy storage applications. [ABSTRACT FROM AUTHOR]

Piezocatalysis, an evolving catalytic technology built on the piezoelectric properties of catalysts, breaks down the barrier between mechanical energy and chemical energy. The potential difference that arises from the mechanical deformation of a piezoelectric material is commonly termed 'piezopotential'. Piezopotential has been demonstrated to facilitate the manipulation of band structure and/or charge carrier separation. Despite significant efforts to design materials and understand the mechanism of piezoelectrically enhanced chemistry through semiconductor physics, there remains an opportunity to review the relationships between catalytic performance and piezo/ferroelectric properties. Herein, we provide a comprehensive summary of the catalytic mechanisms and correlated piezo/ferroelectric physical mechanism in the field of piezocatalysis. A fundamental understanding of piezo/ferroelectric structural design based on solid-state physics can be used to shed light on the future development of piezocatalysis. In addition, the types of piezoelectric materials, the design strategies for catalysis efficiency enhancement, and the up-to-date applications in environment remediation, renewable energy conversion, biomedicine and biotechnology are discussed. Finally, future perspectives for designing and developing highly active piezocatalysts using the guidelines of physicochemical relationships are proposed. [ABSTRACT FROM AUTHOR]