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Lepidopteran pests are destructive pests and have evolved significant resistance to many insecticides. Alternative green control strategies are urgently needed. Our previous research had revealed that overexpression or knockdown of a Plutella xylostella microRNA, pxy-miR-34-5p, could lead to high mortality and severe developmental defects in multiple lepidopteran pests, thus has great potential in lepidopteran pests control. Here, pxy-miR-34-5p was successfully expressed in cruciferous plants, Arabidopsis thaliana and Brassica campestris. Feeding on leaves of transgenic miR-34-5p rape significantly reduced the expression of ecdysone receptor gene PxEcR of P. xylostella by 56.8–70.2%. Bioassays results demonstrated that compared to that of the larvae fed on wild type Arabidopsis, the accumulated mortalities of P. xylostella fed on transgenic miR-34-5p Arabidopsis were significantly increased by 34.9%–52.0%. After feeding on transgenic miR-34-5p rape leaves for four to six days, the highest accumulated corrected mortalities of P. xylostella, Spodoptera frugiperda and Spodoptera exigua larvae reached 100.0%, 94.1%, and 100.0%, respectively. These results indicated that insect microRNAs can be used to control multiple target pests by constructing transgenic crops, which lays an important foundation for the further development of miRNA-based green pest control strategies. [ABSTRACT FROM AUTHOR]

Lepidopteran pests cause enormous economic losses to agriculture globally. The control of these pests relies heavily on chemical insecticides, resulting in severe insecticide resistance and food safety concerns. Therefore, there is an urgent need to develop alternative green strategies. Our previous research revealed that the miRNA of the diamondback moth Plutella xylostella, pxy-miR-34-5p, may be a novel molecular target for multiple lepidopteran pests. However, the application strategy for pxy-miR-34-5p is not yet clear. In this study, pxy-mir-34 was successfully expressed in Escherichia coli to produce artificial miR-34 (amiR-34) on a large scale. Treatment with amiR-34 significantly repressed the expression of the ecdysone receptor (EcR) and 12 other key genes involved in the growth and development of P. xylostella. Feeding bioassays showed that amiR-34 was highly toxic to multiple lepidopteran pests, and pot experiments demonstrated that spraying with amiR-34 led to larval mortalities of 81.7%, 89.3%, and 90.8% for P. xylostella, Spodoptera frugiperda, and Spodoptera exigua, respectively, with a persistence of up to five d. These results indicate that amiR-34 has great potential for controlling multiple lepidopterous pests and they lay an important foundation for developing miRNA-based green pest control strategies. [ABSTRACT FROM AUTHOR]

The economic improvements of a queueing system with two types of customers achieved by service decomposition are examined. The service process for a Type 2 customer can be split into two phases: a basic service and an additional service. The basic service rate is equal to that of the Type 1 customer. Additional services can be viewed as orders stored in inventory and processed when the server is idle. Once a new customer arrives during idle time, the server will provide a basic service to the customer upon his/her arrival. That is, customers have preemptive priority for orders stored in inventory. We obtain a two-dimensional unbounded Markov process and apply the multivariate generating function to derive the stationary probability of the proposed model as well as some performance measures. The condition under which performing service decomposition can improve economic efficiency is also obtained. Both the optimal inventory capacity and the minimum system cost are obtained numerically. Numerical experiments demonstrate the impact of optimal inventory setting on economic improvement efficiency. Finally, simulation experiments prove the correctness of our theoretical analysis. [ABSTRACT FROM AUTHOR]

Simultaneous achievement of high thermal transportation performance and superior mechanical properties in the same thermal management composite film is still a great challenge. Herein, hybrid nano and microdiamonds (hDs) were introduced for the first time to cellulose nanofibers (CNFs) and boron nitride nanosheets (BNNSs) to construct a long-range ordered "sandwiched structure" by vacuum-assisted layer-by-layer self-assembly. Benefiting from the bridging effect of diamond and the long-range ordered structure with a perfect thermally conductive path, the CNF-BNNS-hD composite film exhibits an inplane thermal conductivity of 45.76 W m-1 K-1 and through-plane thermal conductivity of 3.17 W m-1 K-1 at a filler content of 48.2 vol%. Additionally, the diamonds are fixed in the "sandwiched structure" as a support layer, and the BNNSs on both sides of the "sandwiched structure" are used for the slip layers, which significantly enhances the mechanical properties of the composite films, making the CNF-BNNS-hD composite film achieve a tensile strength of 88.6 MPa and an elongation at break of 14.7% as well as excellent insulation performance. In addition, the CNF-BNNS-hD composite film could endure 1500 folds without any fracture, demonstrating the excellent flexibility of the film. Our strategy is very effective for the fabrication of a composite film with high thermal conductivity and robust mechanical properties as well as superior electrical insulation performance. [ABSTRACT FROM AUTHOR]

BACKGROUND: Carboxylesterases (CarEs) are associated with detoxification of xenobiotics, including insecticides, in organism bodies. Overexpression of CarE genes is considered to have an important role in insecticide resistance in insects, however its involvement in multi-insecticide resistance has rarely been reported. This study aimed to assess the function of a CarE gene (Px⊍E8) in resistance to five insecticides in Plutella xylostella. RESULTS: Relative expression of Px⊍E8 in three multi-insecticide-resistant Plutella xylostella populations, GD-2017, GD-2019 and HN, was14.8-, 19.5- and 28.0-fold higher than that in the susceptible population. Exposure to lethal concentrations associated with 25% mortality (LC25) of beta-cypermethrin, chlorantraniliprole, metaflumizone, phoxim and tebufenozide could induce the specific activity of CarEs and increase the relative expression of Px⊍E8. By contrast, knockdown of Px⊍E8 expression dramatically reduced the activity of CarEs and increased the resistance of P. xylostella (GD-2019) larvae to beta-cypermethrin and phoxim by 47.4% and 45.5%, respectively. Further, a transgenic line of Drosophila melanogaster overexpressing Px⊍E8 was constructed and the bioassay results showed that the tolerance of transgenic Drosophila to beta-cypermethrin and phoxim was 3.93- and 3.98-fold higher than that of the untransgenic line. CONCLUSION: These results provide evidence that overexpression of Px⊍E8 is involved in resistance, at least to betacypermethrin and phoxim, in multi-insecticide-resistant P. xylostella populations, which could help in further understanding the molecular mechanisms of multi-insecticide resistance in this pest. [ABSTRACT FROM AUTHOR]

The article presents a study which showed the repair of a mutation in the CYBB gene of CD34 hematopietic stem and progenitor cells (HSPC) from patients with the immunodeficiency disorder X-linked chronogranulomatous disease using CRISPR-associated 9 (Cas9). Topics discussed include optimization of CRISPR-mediated gene repair in patient-derived immortalized T cells, transplantation of corrected P1 CD34 HSPC into NSG immunodeficient mice, and persistence of gene repair after the transplantation.

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