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Topological insulators hold promises to realize exotic quantum phenomena in electronic, photonic, and phononic systems. Conventionally, topological indices, such as winding numbers, have been used to predict the number of topologically protected domain-wall states (TPDWSs) in topological insulators, a signature of the topological phenomenon called bulk-edge correspondence. Here, we demonstrate theoretically and experimentally that the number of TPDWSs in a mechanical Su-Schrieffer-Heeger (SSH) model can be higher than the winding number depending on the strengths of beyond-nearest-neighbor interactions, revealing the breakdown of the winding number prediction. Alternatively, we resort to the Berry connection to accurately characterize the number and spatial features of TPDWSs in SSH systems, further confirmed by the Jackiw-Rebbi theory proving that the multiple TPDWSs correspond to the bulk Dirac cones. Our findings deepen the understanding of complex network dynamics and offer a generalized paradigm for precise TPDWS prediction in potential applications involving localized vibrations, such as drug delivery and quantum computing. Topological insulators are bulk insulators with conducting zero-energy edge states conventionally predicted by topological indices, such as winding numbers in one-dimensional lattices. Here, the authors use the Jackiw-Rebbi theory to reveal that the number of topologically protected zero-energy states can be higher than the winding number. [ABSTRACT FROM AUTHOR]

Extensive unofficial planting of Bt cotton expressing Cry1Ac toxin has occured for the past two decades in northwestern China, and no mandatory refuge policy has been adopted. The status of Cry1Ac susceptibility of Helicoverpa armigera in this region has not been routinely monitored, nor has the susceptibility to Cry2Ab cotton which has not been released in China. The susceptibility of H. armigera populations to both toxins was assessed in 2014 and 2015 in two contrasting cotton farming systems across the region. Over the 2 years, the response to Cry1Ac of the nine H. armigera field populations sampled ranged from 3.16 to 16.94 μg ml−1 for LC50 and 0.013 to 0.741 μg ml−1 for IC50, and the baseline susceptibility of these strains to Cry2Ab ranged from 3.43 to 19.05 μg ml−1 for LC50 and 0.16 to 3.81 μg ml−1 for IC50. There was no significant difference in susceptibility to either Cry1Ac or Cry2Ab between small-holder and broad-acre farming. The susceptibility to Cry1Ac toxin in northwestern China is higher than that in northern China, while there was no difference for Cry2Ab between northwestern China and northern China. With high levels of adoption of Bt cotton and relatively limited natural refuge for H. armigera, it is important to consider resistance management measures for Bt cotton in northwestern China. [ABSTRACT FROM AUTHOR]

Met is the transmembrane tyrosine kinase cell surface receptor for hepatocyte growth factor (HGF) and is structurally related to the insulin receptor (INSR) tyrosine kinase. Here we report that the HGF-Met axis regulates metabolism by stimulating hepatic glucose uptake and suppressing hepatic glucose output. We show that Met is essential for an optimal hepatic insulin response by directly engaging INSR to form a Met-INSR hybrid complex, which culminates in a robust signal output. We also found that the HGF-Met system restores insulin responsiveness in a mouse model of insulin refractoriness. These results provide new insights into the molecular basis of hepatic insulin resistance and suggest that HGF may have therapeutic potential for type 2 diabetes in the clinical setting. [ABSTRACT FROM AUTHOR]