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Abstract High thermal conductive polymers have become more important because equipment requires high performance, high-energy density, and high integration. There are different strategies to make high thermal conductive polymers, among which is the synthesis of polymers in the liquid crystal phase. However, the thermal conductivity of such material is rarely beyond 1 W m−1 K−1 because of the disordered molecular directionality. The disordered directionality between crystal zones limits the thermal conductivity in a specific direction. Here, we show a method for unifying the direction of crystal zones by applying an external electric field on the liquid crystal monomers. Meanwhile, by exposing the transparent equipment and specially designed photopolymerisable monomer in UV light, the liquid crystal monomer is in situ polymerised into a liquid crystal polymer with a high intrinsic thermal conductivity of 1.02 W m−1 K−1. The molecular alignment was characterised and resulted in the resultant high conductivity.

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.

This paper considers a retrial G-queue with collisions, transmission errors, and a finite number of sources, where service and repair time are both general distributions. The number of sources (terminals) is finite and a source cannot generate new requests until the channel (server) finishes its work, i.e., the rate at which new primary requests are generated varies inversely with the number of data frame (customer) in the system. A collision occurs when service requests arrive at a busy channel, and transmission errors prevent data frames from leaving the system after completing service. Two types of arrivals are considered. Negative customers will break down the system in the busy state and remove the customer under service. The application of our model is indicated, with a particular emphasis on communication networks such as the local-area networks (LAN) with CSMA/CD protocol. Recursive formulas have been derived to calculate the stationary joint distributions and the Laplace transform of reliability function by applying the discrete transformations method along with the supplementary variables technique (SVT). Furthermore, the comparative performance and reliability analysis have been conducted numerically. Numerical examples are provided to investigate the sensitivity of different parameters on performance measures and reliability indicators.

Identifying BRCA mutations and homologous recombination deficiency (HRD) is the key to choosing patients for poly (ADP-ribose) polymerase inhibitor (PARPi) therapy. At present, a large amount of research focuses on the application of HRD detection in ovarian cancer. However, few studies have discussed the relationship between HRD detection and postoperative survival in patients with epithelial ovarian cancer (EOC). This study included 38 consecutive patients with EOC who underwent cytoreduction surgery. Owing to tissue availability, only 29 patients underwent molecular profiling and survival analysis. Overall, 21 (72.4%) tumors had HRD scores of ≥42. Mutations in BRCA were observed in 5/29 (17.2%) patients. In this cohort, an HRD score of ≥42 was more common in serous ovarian tumors. We found no statistically significant association between homologous recombination repair (HRR) genes and HRD scores except for tumor protein P53 (TP53) mutation. We also found a strong positive association between HRD scores and chromosomal instability (CIN). In the survival analysis, an HRD score of >23 was correlated with better postoperative progression-free survival (pPFS). With increased depth of research, an appropriate HRD score threshold may serve as a prognostic tool and should be assessed in future studies to predict the clinical value of PARPi.

A highly thermally conductive heat spreader for applications in electronic devices is becoming increasingly demanding, and therefore the removal of excess heat requires an efficient heat dissipating device. Boron nitride nanosheets (BNNSs) were prepared as thermally conductive fillers using hexagonal boron nitride (h-BN) powder as raw material by a water exfoliation method. A composite film was prepared by vacuum filtration using cellulose nanofibers (CNFs) as the substrate with an in-plane thermal conductivity (TC) of 82.4 W m−1 K−1, thermal conductivity enhancement increasing by 9,486% compared to pure cellulose film. Thus, CNF/BNNS composite films are promising as effective thermal interface materials (TIMs) in electronic devices and electronic component applications.

The evolution of resistance to insecticides is well known to be closely associated with the overexpression of detoxifying enzymes. Although the role of glutathione S-transferase (GST) genes in insecticide resistance has been widely reported, the underlying regulatory mechanisms are poorly understood. Here, one GST gene (GSTu1) and its antisense transcript (lnc-GSTu1-AS) were identified and cloned, and both of them were upregulated in several chlorantraniliprole-resistant Plutella xylostella populations. GSTu1 was confirmed to be involved in chlorantraniliprole resistance by direct degradation of this insecticide. Furthermore, we demonstrated that lnc-GSTu1-AS interacted with GSTu1 by forming an RNA duplex, which masked the binding site of miR-8525-5p at the GSTu1-3′UTR. In summary, we revealed that lnc-GSTu1-AS maintained the mRNA stability of GSTu1 by preventing its degradation that could have been induced by miR-8525-5p and thus increased the resistance of P. xylostella to chlorantraniliprole. Our findings reveal a new noncoding RNA-mediated pathway that regulates the expression of detoxifying enzymes in insecticide-resistant insects and offer opportunities for the further understanding of the mechanisms of insecticide and drug resistance. Author summary The development of insecticide resistance in insect pests is a worldwide concern and a major problem in agriculture. Understanding the genetics of insecticide resistance is critical for effective crop protection. Plutella. xylostella (L.), a major pest of cruciferous crops, has developed resistance to almost all kinds of insecticide, and has become one of the most resistant pests in the world. Overexpression of detoxification enzymes is closely associated with insecticide resistance, but researches on their regulatory mechanism are still very limited. Here, GSTu1 was identified to be upregulated in several chlorantraniliprole-resistant P. xylostella populations and was confirmed to be involved in chlorantraniliprole resistance by direct degradation of this insecticide. Further, lnc-GSTu1-AS transcribed from the opposite DNA strand to GSTu1 was identified to be able to enhance the mRNA stability of GSTu1 by blocking miRNA activity, and thus increased the resistance of P. xylostella to chlorantraniliprole. The results provide further insights into the mechanisms underlying metabolic resistance.

Summary: Sickle cell disease (SCD) is caused by a 20A > T mutation in the β-globin gene. Genome-editing technologies have the potential to correct the SCD mutation in hematopoietic stem cells (HSCs), producing adult hemoglobin while simultaneously eliminating sickle hemoglobin. Here, we developed high-efficiency viral vector-free non-footprint gene correction in SCD CD34+ cells with electroporation to deliver SCD mutation-targeting guide RNA, Cas9 endonuclease, and 100-mer single-strand donor DNA encoding intact β-globin sequence, achieving therapeutic-level gene correction at DNA (∼30%) and protein (∼80%) levels. Gene-edited SCD CD34+ cells contributed corrected cells 6 months post-xenograft mouse transplant without off-target δ-globin editing. We then developed a rhesus β-to-βs-globin gene conversion strategy to model HSC-targeted genome editing for SCD and demonstrate the engraftment of gene-edited CD34+ cells 10–12 months post-transplant in rhesus macaques. In summary, gene-corrected CD34+ HSCs are engraftable in xenograft mice and non-human primates. These findings are helpful in designing HSC-targeted gene correction trials.

The rapid development of chip technology has all put forward higher requirements for highly thermally conductive materials. In this work, a new type of material of Fishbone-like silicon carbide (SiC) material was used as the filler in a polyvinylidene fluoride (PVDF) matrix. The silicon carbide/polyvinylidene fluoride (SiC/PVDF) composites were successfully prepared with different loading by a simple mixing method. The thermal conductivity of SiC/PVDF composite reached 0.92 W m−1 K−1, which is 470% higher than that of pure polymer. The results show that using the filler with a new structure to construct thermal conductivity networks is an effective way to improve the thermal conductivity of PVDF. This work provides a new idea for the further application in the field of electronic packaging.

Helicoverpa armigera is a universal pest around the world that has been extensively used as a model organism for agricultural pests. Calcineurin (CAN) is an important Ca2+-dependent phosphatase that is participated in various biological pathways. Here, we revealed that CAN inhibition significantly arrested H. armigera larval development by reducing larvae weight, prolonging development time and reducing pupate rates. Furthermore, CAN serves as an immune activator and regulates antimicrobial peptide (AMP; cecropin D, attacin, and gloverin) expression by binding with relish transcript factor in H. armigera. This study provides a potential target to control H. armigera by using synergistic agents for pesticides or plant-mediated RNA interference technology.

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]