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The two‐dimensional (2D) materials InX (X = O, Se), experimentally available thus far, can become a ferromagnetic half metal under hole doping, though the charge neutral states of them are nonmagnetic semiconductors. Based on such an electronic characteristic, a theoretical model of magnetic tunnel junction (MTJ) is proposed composed only of one of the 2D InX. In doing so, the two semi‐infinite pieces of 2D InX in the half‐metallic state is assumed as the opposite electrodes which are separated by a strip of the same material but in its nonmagnetic state. Owing to the 2D nature of InX, the half metal electrodes of the InX device induced by hole doping can be achieved by using split gating technique. The numerical simulations identify a proper hole doping concentration, at which 100% tunneling magnetoresistance (TMR) ratios can be realized, accompanying an appreciable conductance of majority spin electron under parallel magnetization configuration. Under a finite bias voltage, the TMR ratio remains high. Therefore, the proposed device model is an ideal candidate for future spintronics applications. It enables electrical control of TMR and circumvents the detriment of hetero‐interface disorder inevitable in conventional MTJs. [ABSTRACT FROM AUTHOR]

SUMMARY: Redox homeostasis in plant cells is critical for maintaining normal growth and development because reactive oxygen species (ROS) can function as signaling molecules or toxic compounds. However, how plants fine‐tune redox homeostasis during natural or stress‐induced senescence remains unclear. Cut roses (Rosa hybrida), an economically important ornamental product worldwide, often undergo stress‐induced precocious senescence at the post‐harvest bud stage. Here, we identified RhPLATZ9, an age‐ and dehydration‐induced PLATZ (plant AT‐rich sequence and zinc‐binding) protein, and determined that it functions as a transcriptional repressor in rose flowers during senescence. We also showed that RhWRKY33a regulates RhPLATZ9 expression during flower senescence. RhPLATZ9‐silenced flowers and RhWRKY33a‐silenced flowers showed accelerated senescence, with higher ROS contents than the control. By contrast, overexpression of RhWRKY33a or RhPLATZ9 delayed flower senescence, and overexpression in rose calli showed lower ROS accumulation than the control. RNA‐sequencing analysis revealed that apoplastic NADPH oxidase genes (RhRbohs) were enriched among the upregulated differentially expressed genes in RhPLATZ9‐silenced flowers compared to wild‐type flowers. Yeast one‐hybrid assays, electrophoretic mobility shift assays, dual luciferase assays and chromatin immunoprecipitation quantitative PCR confirmed that the RhRbohD gene is a direct target of RhPLATZ9. These findings suggest that the RhWRKY33a‐RhPLATZ9‐RhRbohD regulatory module acts as a brake to help maintain ROS homeostasis in petals and thus antagonize age‐ and stress‐induced precocious senescence in rose flowers. Significance Statement: It is significant for ornamental qualities of rose flowers to elucidate how to maintain the redox homeostasis during premature, stress‐induced reactive oxygen species (ROS)‐mediated senescence. Here, we identified a brake mechanism of RhWRKY33a‐RhPLATZ9‐RhRbohD module to help maintain ROS homeostasis in petals and thus antagonize age‐ and stress‐induced precocious senescence in rose flowers. [ABSTRACT FROM AUTHOR]

A new method was developed for the simultaneous determination of three catecholamines in urine using aminophenylboronic acid functionalized magnetic nanoparticles extraction followed by high-performance liquid chromatography with electrochemical detection. Novel aminophenylboronic acid functionalized magnetic nanoparticles were prepared by multi-step covalent modification, and characterized by transmission electron microscopy, Fourier-transformed infrared spectroscopy, X-ray diffraction, and vibrating sample magnetometry. With the help of the high affinity between the boronate and cis-diol group, the particles were used for the highly selective separation and enrichment of three major catecholamines, norepinephrine, epinephrine, and dopamine. Effects of the pH of the feed solution, the extraction time, the composition of the buffer solution, the amount of the magnetic particles, the elution conditions, and the recycling of aminophenylboronic acid functionalized magnetic nanoparticles were explored. Under the optimized conditions, 13-17-fold enrichment factors were obtained. The linear ranges were 0.01-2.0 μg/mL for the studied analytes. The limits of detection and quantification were in the range of 2.0-7.9 and 6.7-26.3 ng/mL, respectively. The relative recoveries were in the range of 92-108%, with intraday and interday relative standard deviations lower than 6.8%. This method was successfully applied to analysis of catecholamines in real urine. [ABSTRACT FROM AUTHOR]

Key points: Disease severity in acute radiation rhinosinusitis (ARRS) peaks after radiation therapy.ARRS is mainly local inflammation, manifested by increased pro‐inflammatory cytokines.Intranasal corticosteroids are effective anti‐inflammatory drugs in the treatment of ARRS. [ABSTRACT FROM AUTHOR]

Mass dissolution is one main problems for cathodes in aqueous electrolytes due to the strong polarity of water molecules. In principle, mass dissolution is a thermodynamically favorable process as determined by the Gibbs free energy. However, in real situations, dissolution kinetics, which include viscosity, dissolving mass mobility, and interface properties, are also a critical factor influencing the dissolution rate. Both thermodynamic and kinetic dissolving factors can be regulated by the ratio of salt to solvent in the electrolyte. In this study, concentration‐controlled cathode dissolution is investigated in a susceptible Na3V2(PO4)3 cathode whose time‐, cycle‐, and state‐of‐charge‐dependent dissolubility are evaluated by multiple electrochemical and chemical methods. It is verified that the super‐highly concentrated water‐in‐salt electrolyte has a high viscosity, low vanadium ion diffusion, low polarity of solvated water, and scarce solute−water dissolving surfaces. These factors significantly lower the thermodynamic‐controlled solubility and the dissolving kinetics via time and physical space local mass interfacial confinement, thereby inducing a new mechanism of interface concentrated‐confinement which improves the cycling stability in real aqueous rechargeable sodium‐ion batteries. [ABSTRACT FROM AUTHOR]

Key points: Respiratory epithelial adenomatoid hamartoma (REAH) is easily confused with nasal polyps (NP).The typical manifestation of REAH on CT is the enlargement of bilateral olfactory clefts (OCs).The widening of the OCs in the CT scan is a biomarker for diagnosing REAH associated with NP. [ABSTRACT FROM AUTHOR]

Recently, increasing attention has been paid to the newly emerging area of sodium-ion batteries, as a promising supplement for lithium-ion batteries. Although many cathode materials have been proposed, most of these have limitations for practical applications, such as a low capacity or a poor cycling performance. Here, sodium-deficient O3-Na0.9[Ni0.4Mn x Ti0.6− x]O2 (where x 5 0.1-0.6, abbreviated as NNMT-9415, 9424, 9433, 9442, 9451, and 9460, respectively) materials are introduced, which can be used as the cathode in sodium-ion batteries. Among these materials, the electrochemical behavior of materials with x 5 0.4 and 0.3 is the highest with a higher capacity and better cycling property than the other materials. These can deliver an initial capacity of about 120 mA h g21 in a voltage range of 2.5-4.2 V with a negligible capacity loss even after 100 cycles. The rate capabilities of 82% and 64% at 1 C and 2 C current rates, respectively, are also satisfactory. The good cycling performance and high capacity make these two materials potential candidates as the cathode material for sodium-ion batteries. [ABSTRACT FROM AUTHOR]

Na‐ion batteries have experienced rapid development over the past decade and received significant attention from the academic and industrial communities. Although a large amount of effort has been made on material innovations, accessible design strategies on peculiar structural chemistry remain elusive. An approach to in situ construction of new Na‐based cathode materials by substitution in alkali sites is proposed to realize long‐term cycling stability and high‐energy density in low‐cost Na‐ion cathodes. A new compound, [K0.444(1)Na1.414(1)][Mn3/4Fe5/4](CN)6, is obtained through a rational control of K+ content from electrochemical reaction. Results demonstrate that the remaining K+ (≈0.444 mol per unit) in the host matrix can stabilize the intrinsic K‐based structure during reversible Na+ extraction/insertion process without the structural evolution to the Na‐based structure after cycles. Thereby, the as‐prepared cathode shows the remarkably enhanced structural stability with the capacity retention of >78% after 1800 cycles, and a higher average operation voltage of ≈3.65 V versus Na+/Na, directly contrasting the non‐alkali‐site‐substitution cathode materials. This provides new insights into alkali‐site‐substitution constructing advanced Na‐ion cathode materials. [ABSTRACT FROM AUTHOR]