Engineering and breeding resistant plant varieties are the most effective and environmentally friendly ways to control agricultural pests and improve crop performance. However, the mechanism of plant resistance to pests is poorly understood. Here we used a quantitative mass-spectrometry-based proteomic approach for comparative analysis of expression profiles of proteins in rice leaf sheaths in responses to infestation by the brown planthopper (Nilaparvata lugens Stål, BPH), which is a serious rice crop pest. Proteins involved in multiple pathways showed significant changes in expression in response to BPH feeding, including jasmonic acid synthesis proteins, oxidative stress response proteins, beta-glucanases, protein; kinases, clathrin protein, glycine cleavage system protein, photosynthesis proteins and aquaporins. The corresponding genes of eight important proteins were further analyzed by quantitative RT-PCR. Proteomic and transcript responses that were related to wounding, oxidative and pathogen stress overlapped considerably between BPH-resistant (carrying the resistance gene BPH15) and susceptible rice lines. In contrast, proteins and genes related to callose metabolism remained unchanged and glycine cleavage system protein was up-regulated in the BPH-resistant lines, indicating that they have an efficient and specific defense mechanism. Our results provide new information about the interaction between rice and the BPH.

Au–Ag alloy nanoparticles on titania exhibit superior photocatalytic performance in selective oxidation of methanol to methyl formate.

Internal flow behaviour during melt-pool-based metal manufacturing remains unclear and hinders progression to process optimisation. In this contribution, we present direct time-resolved imaging of melt pool flow dynamics from a high-energy synchrotron radiation experiment. We track internal flow streams during arc welding of steel and measure instantaneous flow velocities ranging from 0.1 m s−1 to 0.5 m s−1. When the temperature-dependent surface tension coefficient is negative, bulk turbulence is the main flow mechanism and the critical velocity for surface turbulence is below the limits identified in previous theoretical studies. When the alloy exhibits a positive temperature-dependent surface tension coefficient, surface turbulence occurs and derisory oxides can be entrapped within the subsequent solid as result of higher flow velocities. The widely used arc welding and the emerging arc additive manufacturing routes can be optimised by controlling internal melt flow through adjusting surface active elements.

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Magnetic skyrmions, a kind of localized spin texture topologically protected in magnetic materials, characterized by smaller size and much lower manipulating current density in comparison with ferromagnetic domain walls, are highlighted as potential information carriers for high-density magnetic storage devices. For technological applications, the stabilization of skyrmions in a temperature range around room temperature under a low magnetic field is essential. Here, we demonstrate the formation of magnetic biskyrmions in a low magnetic field at room temperature in a centrosymmetric hexagonal MnPdGa magnet via Lorentz transmission electron microscopy in combination with transport and magnetic measurements. High-density biskyrmions are generated at 300 K in a magnetic field of 0.15 T. In addition, biskyrmions can be generated from ferromagnetic domains and partly remained at zero field when the magnetic field is decreased. A large topological Hall resistivity is observed near room temperature. Furthermore, a wide temperature and magnetic-field window for biskyrmions is deduced from transport and magnetic properties. The simultaneous features of high-density and low magnetic field near room temperature in a single-component material make MnPdGa a promising candidate for future skyrmion-based topological spintronic applications.

An unprecedented catalytic asymmetric inverse-electron-demand aza-Diels-Alder reaction of indoles with in situ formed azoalkenes is reported. A diverse set of [2,3]-fused indoline heterocycles were achieved in generally good yields (up to 97 %) with high regioselectivity and diastereoselectivity (>20:1 d.r.), and with excellent enantioselectivity (up to 99 % ee).

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Carbon nanotubes (CNTs), a new form of pure carbon, have an extremely unique and desirable combination of mechanical, thermal and electrical properties. The CNT reinforced polymer composites have the potential to meet the electrical and mechanical requirements of various industries. In this paper, CNT reinforced epoxy adhesives was developed. Firstly, the distribution of the carbon nanotubes in the polymer matrix, which