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Abstract Background This study aims to analyse changes in urinary kidney injury markers in children with Mycoplasma pneumoniae pneumonia (MPP), investigate the risk factors for MPP-related acute kidney injury (AKI) and establish a model to predict MPP-related AKI. Methods Ninety-five children were enrolled based on the study’s inclusion and exclusion criteria. They were divided into a severe MPP (SMPP) group and a non-SMPP group and then into an AKI group and a non-AKI group according to the presence of AKI. A univariate logistic regression analysis was performed to explore the early risk factors for AKI. Based on a multivariate logistic regression analysis and a least absolute shrinkage and selection operator regression analysis, appropriate variables were selected to establish a prediction model, and R 4.2.2 software was used to draw nomograms and generate a dynamic nomogram website. Results Seven urinary kidney injury markers were abnormally elevated in the SMPP group and the non-SMPP group: urinary N-acetyl-β-D-glucosaminidase (NAG), β2-microglobulin, α1-microglobulin, retinol-binding protein, urinary immunoglobulin G, urinary transferrin and urinary microalbumin. Sixteen children were identified with AKI during hospitalisation. The AKI group had higher levels of urinary NAG, α1-microglobulin, β2-microglobulin, urinary microalbumin, urinary transferrin and retinol-binding protein than the non-AKI group (P

Multifunctional, wearable, and durable textiles integrated with smart electronics have attracted tremendous attention. However, it remains a great challenge to balance new functionalities with high-temperature stability. Herein, textile-based pressure sensors with excellent electromagnetic interference (EMI) shielding, Joule heating, and high-temperature resistance were fabricated by constructing graphene/SiC (G/SiC) heterostructures on carbon cloth via laser chemical vapor deposition (LCVD). The resultant textiles exhibited excellent EMI efficiency of 74.2 dB with a thickness of 0.45 mm, Joule heating performance within a low working voltage (V) range of 1–3 V, and fast response time within 20 s. These properties arose from multiple reflections, interfacial polarization, and high conductivity due to the numerous amounts of nanoscale G/SiC heterostructures. More importantly, G/SiC/carbon fibers (CFs) demonstrated well high-temperature resistance with a heat resistance index (THRI) of 380.2 ℃ owing to the protection of a coating layer on the CFs upon oxidation. Meanwhile, the G/SiC/CFs presented good pressure-sensing performance with high sensitivity (S) of 52.93 kPa−1, fast response time of 85 ms, and a wide pressure range of up to 186 kPa. These features imply the potential of the G/SiC/CFs as efficient EMI shielding, electrical heater, and piezoresistive sensor textiles.

Abstract Polymer dielectrics have drawn great attentions for applications in advanced electronic devices and power grids because of their high breakdown strength, low dielectric loss, and excellent flexibility. However, the low energy density in polymer dielectric capacitors will hinder the continuous miniaturization of electrical systems. In this work, ultraviolet irradiation is demonstrated to greatly enhance the breakdown strength and energy density of polypropylene. Dramatically improved breakdown strength of 867 MV/m and discharged energy density of 8.0 J/cm3, together with the high energy efficiency of >90%, were simultaneously achieved in polypropylene after ultraviolet irradiation. Our research shows that proper ultraviolet irradiation can effectively improve the energy density of polypropylene without sacrificing its high charge‐discharge efficiency, being potential for applications in power electronics and pulse electric systems.

Summary: Numerous voids among the incompact layer-structure of MXene films result in their low ambient stability and poor innate conductivity for electromagnetic interference (EMI) shielding. Herein, we report a bridging-sheet-size-controlled densification process of MXene films by applying graphene oxide (GO) as a bridging agent. Specifically, the sheet size of GO is tailored to quantify a negative correlation of sheet size with densification for directing the preparation of most compact MXene-GO films. Benefiting from the shortest electron-transport-distance in the most compact structure, the conductivity of the MXene-GO film achieves 1.7 times (∼1.6 × 105 S/m) that of MXene film. The EMI shielding performance (5.2 × 106 dB/m) reaches the record-value among reported MXene films at 10 μm-scale thickness. Moreover, the compact structure boosts the ambient stability of MXene-GO films where the conductivity and EMI shielding performance remain 88.7% and 90.0% after 15 days, respectively. The findings rationale the structure-activity relationship of compact MXene films for flexible electronics.

Abstract Addressing microstructure-property relations of polymer nanocomposites is vital for designing advanced dielectrics for electrostatic energy storage. Here, we develop an integrated phase-field model to simulate the dielectric response, charge transport, and breakdown process of polymer nanocomposites. Subsequently, based on 6615 high-throughput calculation results, a machine learning strategy is schemed to evaluate the capability of energy storage. We find that parallel perovskite nanosheets prefer to block and then drive charges to migrate along with the interfaces in x-y plane, which could significantly improve the breakdown strength of polymer nanocomposites. To verify our predictions, we fabricate a polymer nanocomposite P(VDF-HFP)/Ca2Nb3O10, whose highest discharged energy density almost doubles to 35.9 J cm−3 compared with the pristine polymer, mainly benefit from the improved breakdown strength of 853 MV m−1. This work opens a horizon to exploit the great potential of 2D perovskite nanosheets for a wide range of applications of flexible dielectrics with the requirement of high voltage endurance.

Millimeter wave antennas have the advantage of high directivity, miniaturization, high resolution and data transfer speed, wide bandwidth, and lower latency. In this work, a millimeter wave planar array antenna (PAA) with the characteristics of wideband and low sidelobes, which consists of eight identical linear array antenna (LAA) based on Ti3C2 MXene, is designed and fabricated. It is the first time that MXene antennas are proposed for a 5G millimeter wave antenna application. MXene PAA has a high realized gain of 22.22 dBi and a −10 dB impedance bandwidth of measurement covering the range from 24 GHz to 28 GHz, including the 5G FR2—n258 frequency band. With Chebyshev current distribution, the MXene PAA has a half-power beam width of 10.2° and 10.8° in the xoz-plane and yoz-plane radiation patterns with the sidelobes levels below −20 dB, respectively. Therefore, MXene PAA is suitable for 5G mobile communication applications.

Chemically exfoliated nanosheets have been extensively employed as functional nanofillers for the fabrication of polymer nanocomposites due to their remarkable electrical, magnetic and optical properties. However, achieving a good dispersion of charged nanosheets in polymer matrix, which will determine the performance of polymer nanocomposites, remains a challenge. Herein, we investigated the dispersion and aggregation behavior of negatively charged Ca2Nb3O10 (CNO) perovskite nanosheets in negatively charged sodium alginate (SA) aqueous dispersion using dynamic light scattering (DLS). When CNO nanosheets meet with SA, aggregation and coagulation inevitably occurred owing to the absorption of SA on nanosheets. By controlling the electrostatic attraction between positively charged poly(ethylene imine) (PEI) and negatively charged SA, the charge density and hydrodynamic size of SA can be tuned to enable the good dispersion of CNO nanosheets in SA. This result may provide a new strategy to achieve the good dispersion of charged nanosheets in charged polymers for the rational design of multifunctional nanocomposites.

Abstract The atomic or molecular assembly on 2D materials through the relatively weak van der Waals interaction is quite different from the conventional heteroepitaxy and may result in unique growth behaviors. Here, it is shown that straight 1D cyanide chains display universal epitaxy on hexagonal 2D materials. A universal oriented assembly of cyanide crystals (AgCN, AuCN, and Cu0.5Au0.5CN) is observed, where the chains are aligned along the three zigzag lattice directions of various 2D hexagonal crystals (graphene, h‐BN, WS2, MoS2, WSe2, MoSe2, and MoTe2). The potential energy landscape of the hexagonal lattice induces this preferred alignment of 1D chains along the zigzag lattice directions, regardless of the lattice parameter and surface elements as demonstrated by first‐principles calculations and parameterized surface potential calculations. Furthermore, the oriented microwires can serve as crystal orientation markers, and stacking‐angle‐controlled vertical 2D heterostructures are successfully fabricated by using them as markers. The oriented van der Waals epitaxy can be generalized to any hexagonal 2D crystals and will serve as a unique growth process to form crystals with orientations along the zigzag directions by epitaxy.

Abstract Two-dimensional (2D) mesoporous VO2 microarrays have been prepared using an organic–inorganic liquid interface. The units of microarrays consist of needle-like VO2 particles with a mesoporous structure, in which crack-like pores with a pore size of about 2 nm and depth of 20–100 nm are distributed on the particle surface. The liquid interface acts as a template for the formation of the 2D microarrays, as identified from the kinetic observation. Due to the mesoporous structure of the units and high conductivity of the microarray, such 2D VO2 microarrays exhibit a high specific capacitance of 265 F/g at 1 A/g and excellent rate capability (182 F/g at 10 A/g) and cycling stability, suggesting the effect of unique microstructure for improving the electrochemical performance.

A flexible polymer nanocomposite has been developed via introducing Nd-doped BaTiO3 nanoparticles into the poly(vinylidene fluoride). This nanocomposite delivers a discharged energy density up to 12.5 J/cm3 under an electric field of 420 kV/mm with only a small loading of 1 vol.% Nd-BaTiO3. High discharged energy density, mechanical flexibility, light weight, ease fabrication and low cost makes it attractive for advanced microelectronics and electrical power systems. Our results demonstrate that ceramics with giant dielectric permittivity as viable fillers for polymer nanocomposite dielectrics with higher energy density.

Abstract An excellent ternary composite photocatalyst consisting of silver orthophosphate (Ag3PO4), attapulgite (ATP), and TiO2 was synthesized, in which heterojunction was formed between dissimilar semiconductors to promote the separation of photo-generated charges. The ATP/TiO2/Ag3PO4 composite was characterized by SEM, XRD, and UV-vis diffuse reflectance spectroscopy. The co-deposition of Ag3PO4 and TiO2 nanoparticles onto the surface of ATP forms a lath-particle structure. Compared with composite photocatalysts consisting of two phases, ATP/TiO2/Ag3PO4 ternary composite exhibits greatly improved photocatalytic activity for degradation of rhodamine B under simulated solar irradiation. Such ternary composite not only improves the stability of Ag3PO4, but also lowers the cost by reducing application amount of Ag3PO4, which provides guidance for the design of Ag3PO4- and Ag-based composites for photocatalytic applications.

The energy storage density of pure polymers is usually limited by their low intrinsic dielectric constants (εeff). Integrating polymer matrix with ceramic particles with high εeff values has been one powerful approach to enhance the εeff values of polymer composites and thus their energy storage density. In this study, we report a flexible polymer-based composite by introducing Nd-doped BaTiO3 (NBT) nanoparticles (εeff over 3×105) into the poly(vinylidene fluoride) (PVDF). The phase of PVDF and its dielectric behavior could be adjusted by varying the NBT loadings. Composites including less than 5 vol.% NBT loading exhibited enhanced dielectric constants and maintained high breakdown strength. With a quenching process, the composite delivers a discharged energy density up to 7.91 J/cm3 at an electric field of 350 kV/mm with 2.5 vol.% NBT loading, which is 140% more than that of pure PVDF at the same electric field.

The energy storage density of pure polymers is usually limited by their low intrinsic dielectric constants (ε eff). Integrating polymer matrix with ceramic particles with high ε eff values has been one powerful approach to enhance the ε eff values of polymer composites and thus their energy storage density. In this study, we report a flexible polymer-based composite by introducing Nd-doped BaTiO3 (NBT) nanoparticles (ε eff over 3×105) into the poly(vinylidene fluoride) (PVDF). The phase of PVDF and its dielectric behavior could be adjusted by varying the NBT loadings. Composites including less than 5 vol.% NBT loading exhibited enhanced dielectric constants and maintained high breakdown strength. With a quenching process, the composite delivers a discharged energy density up to 7.91 J/cm3 at an electric field of 350 kV/mm with 2.5 vol.% NBT loading, which is 140% more than that of pure PVDF at the same electric field. [ABSTRACT FROM AUTHOR]

Motivation: Small GTPase RhoA regulates cell-cycle progression via several mechanisms. Apart from its actions via ROCK, RhoA has recently been found to activate a scaffold protein MEKK1 known to promote ERK activation. We examined whether RhoA can substantially affect ERK activity via this MEKK1-mediated crosstalk between RhoA and EGFR-ERK pathway. By extending the published EGFR-ERK simulation models represented by ordinary differential equations, we developed a simulation model that includes this crosstalk, which was validated with a number of experimental findings and published simulation results. Results: Our simulation suggested that, via this crosstalk, RhoA elevation substantially prolonged duration of ERK activation at both normal and reduced Ras levels. Our model suggests ERK may be activated in the absence of Ras. When Ras is overexpressed, RhoA elevation significantly prolongs duration of ERK activation but reduces the amount of active ERK partly due to competitive binding between ERK and RhoA to MEKK1. Our results indicated possible roles of RhoA in affecting ERK activities via MEKK1-mediated crosstalk, which seems to be supported by indications from several experimental studies that may also implicate the collective regulation of cell fate and progression of cancer and other diseases. Contact: phacyz@nus.edu.sg Supplementary information: Supplementary data are available at Bioinformatics online. [ABSTRACT FROM AUTHOR]

In the structure of the polymeric title compound, [ZnCl(2)(C(12)H(18)N(4))](n) or [ZnCl(2)(L)](n), where L = 1,1'-(hexane-1,6-di-yl)diimidazole, the Zn(II) centre is coordinated by two N atoms of two different L ligands and by two chloride anions in a distorted tetra-hedral geometry. The organic ligand links adjacent metals to form a polymeric chain along the c axis. The chains are further connected into layers parallel to the bc plane by inter-molecular C-H⋯Cl hydrogen bonds. Two C atoms of the central hexyl chain are disordered over two positions with site-occupancy factors of 0.5.