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Pathogenic microorganisms can impact the behavior and physiology of herbivores by direct or indirect means. This study demonstrated that yellow peach moth Conogethes punctiferalislarvae feeding on Penicillium-infected apples exhibited significantly longer body length and weight parameters compared to the control group. The sequencing of gut 16S rRNA showed a significant increase in the diversity and abundance of bacteria in the larvae feeding on Penicillium-infected apples. Additionally, transcriptomic sequencing of the larval gut indicated significant upregulation of genes related to digestion and cuticle formation after consuming Penicillium-infected apples. Furthermore, enzyme activity assays revealed notable changes in the trypsin and lipase activity. Consequently, these alterations in gut microbiota structure, diversity, and gene expression levels may underlie the observed growth and developmental variations in C. punctiferalislarvae mediated by pathogenic microorganisms. This study holds theoretical significance for a deeper understanding of the tripartite interaction among microorganisms, insects, and plants as well as for the development of novel pest control measures based on gut microbiota.

Two-dimensional (2D) iron/cobalt metal–organic framework nanosheets (Fe/Co-MOF NSs) were synthesized via the cooperative self-assembly reaction of Fe3+/Co2+and terephthalic acid at room temperature. The as-prepared 2D Fe/Co-MOF NSs display superior performance in catalysis of the chemiluminescence (CL) reaction between luminol and H2O2. The CL spectrum, UV–vis absorption spectroscopy, radical scavenger experiments, and electron spin resonance (ESR) spectroscopy are utilized to research the possible CL mechanism of the luminol-H2O2–Fe/Co-MOF NSs system. All results indicate that Fe/Co-MOF NSs present outstanding peroxidase-like activity and could catalyze H2O2to produce 1O2, O2·–, and ·OH, which could react rapidly with the luminol anion radical and result in strong CL. With the highly efficient CL of the luminol-H2O2–Fe/Co-MOF NSs system, a sensitive sensor for the detection of dopamine (DA) is developed based on the inhibitory effect of DA on the CL intensity. Good linearity over the range of 50–800 nM is achieved with a limit of detection of 20.88 nM (S/N = 3). This research demonstrates that 2D Fe/Co-MOF NSs is a highly effective catalyst for luminol CL reaction and has great application potential in the CL field.

An O(nm)-time network simplex algorithm for searching a tree of shortest paths from a given node to all other nodes in a network of n nodes and m directed arcs was studied. The algorithm's worst-case running time proved to be as fast as any proved polynomial algorithm. In addition, it was observed to be faster than previous algorithms from proposed simplex algorithm problems. As part of the study, the gap between simplex and non-simplex shortest path algorithms was closed by giving the shortest path simplex algorithm at most (n-1)(n-2)/2 pivots and O(nm) time. The shortest path problem concerns finding directed paths of shortest length from a given node in a directed network with assigned arc lengths to all other nodes.

Simultaneous detection of multiple targets is of great significance for accurate disease diagnosis. Herein, based on duplex-specific nuclease (DSN) assisted signal amplification and the toehold-mediated strand displacement reaction (TSDR), we constructed an electrochemical biosensor with high sensitivity and high specificity for dual-target detection. MiRNA-141 and miRNA-133a were used as the targets, and ferrocene (Fc) and methylene blue (MB) with significant peak potential differentiation were used as the electrochemical signal probes. The elaborately designed hairpin probe H1, which was fixed on the electrode surface, could be hybridized with the target miRNA-141 to perform signal amplification by the DSN-assisted enzyme cleavage cycle; thus, miRNA-141 could be detected by Fc signal changes at 0.41 V. The hairpin H1 can also combine with the MB-labeled signal probe (SP) output from miRNA-133a-induced TSDR, and the detection of miRNA-133a can be realized according to the response signal generated by MB at −0.26 V. The two sensing lines are independent of each other, and there is no mutual interference in the detection process. Therefore, two independent detection lines could be connected in series, and the simultaneous detection of two targets can be achieved on a single electrode. This novel detection strategy provides a new way to simultaneously detect different biomarkers.

•The immunochromatographic assay was established in combination with TRFIA technology.•TRFIA technology effectively improves the sensitivity of the detection for TDH.•This method can effectively detect TDH in seafood samples.

Abstract: Replenishing item pools for on-line ability testing requires innovative and efficient data collection designs. By generating localD-optimal designs for selecting individual examinees, and consistently estimating item parameters in the presence of error in the design points, sequential procedures are efficient for on-line item calibration. The estimating error in the on-line ability values is accounted for with an item parameter estimate studied by Stefanski and Carroll. LocallyD-optimaln-point designs are derived using the branch-and-bound algorithm of Welch. In simulations, the overall sequential designs appear to be considerably more efficient than random seeding of items.

Abstract: This paper presents a new dual network simplex algorithm for the minimum cost network flow problem. The algorithm works directly on the original capacitated network and runs in O(mn(m +n logn) logn) time for the network withn nodes andm arcs. This complexity is better than the complexity of Orlin, Plotkin and Tardos’ (1993) dual network simplex algorithm by a factor ofm/n.