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Hundreds of neurotoxic insecticides are currently in use. However, only a few direct targets have been identified. Here, using Drosophila and the insecticide flonicamid, we identified nicotinamidase (Naam) as a previous unidentified molecular target for an insecticide. Naam is expressed in chordotonal stretch-receptor neurons, and inhibition of Naam by a metabolite of flonicamid, TFNA-AM (4-trifluoromethylnicotinamide), induces accumulation of substrate nicotinamide and greatly inhibits negative geotaxis. Engineered flies harboring a point mutation in the active site show insecticide resistance and defects in gravity sensing. Bees are resistant to flonicamid because of a gene duplication, resulting in the generation of a TFNA-AM-insensitive Naam. Our results, in combination with the absence of genes encoding Naam in vertebrate genomes, suggest that TFNA-AM and potential species-specific Naam inhibitors could be developed as novel insecticides, anthelmintics, and antimicrobials for agriculture and human health.

The international standards IEEE 1474 and IEC 62290 for fully automatic operation (FAO) systems in urban rail transit were respectively set by IEEE-SA (institute of electrical and electronics engineers-standard association) and IEC (international electrotechnical commission) in 1999 and 2004. These two standards are different but related. In this paper, the working progress, relevance, the driverless definition, application scope, architecture, functional requirements and focus issues of IEC 62290 and IEEE 1474 are compared and analyzed respectively. IEEE 1474 is the theoretical foundation for research and development personnel in the field of railway signaling, which is applicable to operation control systems of urban rail transit, trunk railways and medium to high speed maglev, and IEC 62290 is more suitable for FAO systems in urban rail transit.

This study proposed an innovative automated approach to differentiation of the vocabulary proficiency of Chinese speakers. A robust K-means algorithm was designed to compare the oral proficiency between L1 and L2 Chinese speakers regarding lexical richness and how relatively effective the various lexical measures were in performing the differentiation task. Eighteen lexical richness measures were surveyed and compared using the clustering analysis. The effectiveness of each selected measure as well as an overall evaluation of all the measures for the concerned differentiation tasks were comprehensively calibrated. The results demonstrate that, while the L1 versus L2 group difference in lexical richness was observed with statistical significance for each of the chosen measures, the clustering and membership prediction accuracy of individual speakers varied greatly from one measure to another. The implication is that a more fully defined metric of lexical richness is still a worthwhile endeavor for language proficiency assessment, with optimal directions for such endeavors discussed in the concluding remarks.

While the public sector is traditionally the sole provider for much of infrastructure, the pendulum is shifting in light of the enormous investment gap. Across the Global South, public utilities and planning agencies are engaging with the private sector to help bridge the gap. What are the key patterns of private participation in infrastructure (PPI) across countries in the Global South? What macro factors underscore such private participation? These research questions motivate this paper, focusing on five infrastructure sectors across the Global South and its regions. Following a historical synthesis of the changing balance of public and private provision, the paper outlines recent patterns of PPI. Drawing from a World Bank database, a regression analysis includes key macro-level predictors for private sector financing, for both the number of projects and stock of investment. Key results point to the importance of market size and in turn the potential for risk diversification, as well as a set of governance factors underlining investor confidence and stable environment. [ABSTRACT FROM AUTHOR]

The self‐assembly of the π‐conjugated 1,4‐di(1H‐imidazol‐1‐yl)benzene (dib) and 4,4′‐di(1H‐imidazol‐1‐yl)‐1,1′‐biphenyl (dibp) ligands together with 4′‐(3,4‐ dicarboxylphenyloxy)‐4‐biphenylcarboxylic acid (H3L) reacts with metal Zn (II) salts to construct two new coordination polymers (CPs), namely [Zn (dib)(HL)(H2O)] (1) and [Zn (dibp)(HL)] (2). Fluorescence measurements reveal that 1 and 2 could display a highly sensitive fluorescence response toward Hg2+ and nitrofurazone (NFZ). Fluorescence investigations suggest that 1 and 2 are promising multi‐responsive sensing materials for detecting Hg2+ and NFZ through fluorescence quenching (turn‐off). The limits of detection toward Hg2+ ions are 0.221 μM and 0.124 μM, while the limits of detection toward NFZ are 0.757 μM and 0.960 for 1 and 2, respectively. Interestingly, these Hg2+ and NFZ selective sensing processes can even be completed by the reusable CPs detected by the naked eyes. Hirshfeld surfaces and fingerprint plots are extensively used to investigate intermolecular interactions, which play a crucial role in creating diverse supramolecular designs that can be compared. [ABSTRACT FROM AUTHOR]