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AbstractKeteleeria evelyniana Mast var. pendula Hsüeh, a typical plant species of extremely small population, is faced to be endangered. The complete chloroplast (cp) genome of K. evelyniana var. pendula has been assembled and annotated for the first time in this study. The complete genome in length was found to be 117,139 bp. The genome annotation revealed a total of 118 genes, including 34 transfer RNA (tRNA) genes, 4 ribosomal RNA (rRNA) genes, and 80 protein-coding genes. The maximum-likelihood phylogenetic tree supported that K. evelyniana var. pendula, K. fortune, K. evelyniana, and K. davidiana are clustered in one branch. This complete chloroplast genome helped us to understand the evolution of K. evelyniana var. pendula. These results laid the foundation for future studies on the conservation of this species.

When subjected to complicated thermal alternation, the low thermal conductivity (k) of polymerbonded explosives (PBXs) will induce high thermal stress, which will undermine the safety and reliability of the explosives by causing cracks or damage. However, it has been proven to be a challenge to efficiently increase the k of PBXs due to the high interfacial thermal resistance (ITR) and intrinsic defects of their conductive nanofillers. By introducing AgNWs with a high aspect ratio into graphene, this study constructed a novel multi-dimensional high-k nanofiller composed of one-dimensional (1D) silver nanowires (AgNWs) and two-dimensional (2D) graphene, namely gra@AgNWs. The AgNWs decorated could remedy the intrinsic defects of graphene by passing through the interspaces within graphene nanosheets to form connections as bridges. Consequently, the k of energetic polymer composites increased significantly by 89% from 0.425 ​W ​m−1 ​K−1 to 0.805 ​W ​m−1 ​K−1 at ultralow filler loading of 0.5 ​wt%. Furthermore, the temperature gradients and thermal stress in the composite cylinder decreased significantly under complicated thermal changes owing to the enhanced k. As quantitatively demonstrated through the fitting of experimental data using a theoretical model, AgNWs significantly decreased the ITR, paving highways” for phonon transfer between adjacent graphene nanosheets. Hence an expected synergistic effect of heat transfer was produced in the composites. This study provides new insights into the design and preparation of highly thermally conductive composites.

Realizing effective enhancement to the structure of interface region between explosive crystals and polymer binder plays a key role in improving the mechanical properties of the current polymer bonded explosives (PBXs). Herein, inspired by the structure of natural nacre which possesses outstanding mechanical performance, a kind of nacre-like structural layer is constructed in the interface region of PBXs composites, making use of two-dimensional graphene sheets and one-dimensional bio-macromolecules of cellulose as inorganic and organic building blocks, respectively. Our results reveal that the constructed nacre-like structural layer can effectively improve the interfacial strength and then endow the PBXs composites with significantly enhanced mechanical properties involving of creep resistance, Brazilian strength and fracture toughness, demonstrating the obvious advantage of such bioinspired interface structure design strategy. In addition, the thermal conduction performance of PBXs composites also exhibits noticeable enhancement due to the remarkable phonon transport capability endowed by the as-designed nacre-like structural layer. We believe this work provides a novel design route to conquer the issue of weak interfacial strength in PBXs composites and greatly increase the comprehensive properties for better meeting the higher requirements proposed to the explosive part of weapon equipment in new era.

High melting point paraffin wax (HPW) is a novel desensitizer that has the potential to achieve low sensitivity of energetic crystals, such as 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX). However, first-principles calculations confirmed that interface deterioration occurred due to a weak interfacial connection. In this work, the polydopamine (PDA)/HPW/PDA with a sandwich-like interfacial structure was prepared using three simple steps to improve safety performance, thermal stability, and mechanical properties. The theoretical and experimental results suggested that the PDA acted as a double-sided tape to adhere to the adjacent HMX/HPW layer or HPW/polymer binder layer, thus substantially enhancing the interfacial interaction. While maintaining higher safety performance (impact energy: 11∼13 ​J) than that of HMX (5 ​J), the new design improved the β-δ polymorphic transition temperature of HMX to 219.4 ​°C for HMX@PDA@HPW@PDA, which was higher than that of HMX@HPW (202.8 ​°C) and core@double-shell HMX@PDA@HPW (208.9 ​°C). Among the modified energetic composites, polymer-bonded explosives (PBXs) based on HMX@PDA@HPW@PDA exhibited the optimum mechanical performance, including the storage modulus and tensile fracture energy, which were 43.5% and 77.1% higher than those of PBXs based on raw HMX, respectively. The achieved favorable systematical enhancement in thermal stability, mechanical properties, and safety performance shows that such a sandwich-like interfacial structure has great potential for application for HMX-based formulation used in complex environments.

Abstracts: The mechanical strength was influenced by the quality of the crystal and interfacial interaction between energetic particles and polymeric binders. In this work, rod-like and hairy-spherical 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105) with a high crystal quality was modified by polydopamine (PDA) and hyperbranched polymers (HBP) grafting. The morphology of modified LLM-105 changed into a rough surface, resulting in the obvious enhancement of surface energies and adhesion work with the fluoropolymer. Further, the thermal behavior was slightly affected after surface modification due to the decomposition latent of PDA and HBP. Owing to the combined e chemical bonding of PDA and interlocking interaction of HBP, the creep resistance and mechanical strength of the modified LLM-105-based polymer bonded explosives (PBXs) were significantly improved, assisted by quantitative analysis of the interfacial strength. This strategy may provide insights to other composites requiring high mechanical performance.

An object detection framework using thermal infrared (TIR) cameras is proposed to meet the needs of an advanced driver assistance system (ADAS) operating at night‐time and in low‐visibility conditions. The proposed detection framework, referred to as TIR‐YOLO‐ADAS, is an improvement of YOLOX for TIR object detection in ADAS. First, to address the disadvantages of TIR objects, the part of the attention mechanism is designed to enhance the discriminative ability of feature maps in the spatial and channel dimensions. Second, a focal loss function is used as the confidence loss function to enable the framework to focus on detection tasks of difficult, misclassified targets in the process of network training. The results of the ablation experiment on the Forward‐looking infrared (FLIR) thermal ADAS dataset indicate that the proposed framework significantly improves the performance of TIR object detection. Comparative experimental results further show that TIR‐YOLO‐ADAS performs favourably when compared with three representative detection algorithms. To evaluate the practicality and feasibility of the proposed framework in various applications, a qualitative assessment in real road scenarios was conducted. The experimental results confirm that the proposed framework performs promisingly and could be integrated into vehicle platforms as an ADAS module. [ABSTRACT FROM AUTHOR]

Pterospermum menglunense is the endangered plant species of the genus Pterospermum in the family Sterculiaceae. In the study, the complete genome was 162,421bp in length, including of two inverted repeats (IRA and IRB, 25,572 bp), separated by a large single-copy region (LSC, 90,754 bp) and a small single-copy region (SSC, 20,523 bp). The genome annotation reveals a total of 132 genes, including 37 transfer RNA (tRNA) genes, 8 ribosomal RNA (rRNA) genes, and 87 protein-coding (PCG) genes. The phylogenetic tree showed P. menglunense is closely related to Pterospermum kingtungense.

In this study, Cansjera rheedei J. F. Gmelin is an important role in the phylogeny and evolution of Opiliaceae plant. The chloroplast genome of C. rheedei is 144,306 bp in size, with an average GC content of 37.5%. The complete chloroplast genome has a typical quadripartite structure, including a large single copy (LSC) region (82,773 bp) and a small single copy (SSC) region (9745 bp), which were separated a pair of inverted repeats (IRs, 25,894 bp). This plastome contained 101 different genes, including 67 protein-coding genes (PCGs), 30 tRNA genes and four rRNA genes. The chloroplast genome of C. rheedei has completed that will be based on the phylogeny and genomic studies in the family Opiliaceae.

An extended gate tunneling field effect transistor (EG‐TFET) with narrow bandgap material InN as a label‐free dielectric modulated biosensor is proposed and investigated. An optimum structure of the proposed InN TFET is given by comparing on‐state and ambipolar current. The on‐state current is improved by increasing the length of source overlap, for the rate of forward tunneling increases. Further, the ambipolar current is suppressed by increasing the length of drain offset, for the rate of backward tunneling decreases. A cavity under the gate electrode is formed for sensing biomolecules by dielectric modulation. The performance of EG‐TFET biosensor corresponding to varied dielectric constants of biomolecule is analyzed. In addition, the impacts of charge density and partial filled cavity on the drain current sensitivity are investigated. The electric field, surface potential and energy band profiles are used to explain the working principle of the EG‐TFET biosensor. The simulations reveal that the drain current sensitivity is 3.72 × 107 when neutral biomolecule with κ = 12 is immobilized in the cavity. A linearity fit verification is given, and the results of current sensitivity reveal a good linearity of the EG‐TFET biosensor with fitness coefficient γ2 > 0.99. [ABSTRACT FROM AUTHOR]

Abstract Background Ceftiofur Sodium is widely used in China. Our aim was to determine Ceftiofur Sodium activity and optimize dosing regimens against the pathogen Haemophilus parasuis using an in vitro and ex vivo pharmacokinetics/pharmacodynamics modeling approach. By adopting these strategies, we wanted to extend the effective life of Ceftiofur Sodium in reduce drug-resistance in pigs. Results We established an H. parasuis infection model in pigs, and assessed the pharmacokinetics of Ceftiofur Sodium in both healthy and infected animals. After Ceftiofur Sodium (10 mg/kg, i.m.) administration to healthy and H. parasuis-infected pigs, plasma based desfuroylceftiofur (a metabolite of Ceftiofur Sodium) was measured by High Performance Liquid Chromatography. The pharmacokinetics of Ceftiofur Sodium (desfuroylceftiofur) was consistent with a two-compartment open model, with first-order absorption. We observed no significant differences (P > 0.05) in pharmacokinetic parameters between healthy and infected pigs. Pharmacodynamics data showed that Ceftiofur Sodium was highly inhibitory against H. parasuis, with MIC, MBC, and MPC values of 0.003125, 0.0125 and 0.032 μg/mL, respectively. Desfuroylceftiofur in plasma also had strong bactericidal activity. Almost all H. parasuis cultured in plasma medium of Ceftiofur Sodium-inoculated healthy pigs, at each time point, were killed within 24 h. A weaker antibacterial activity was measured in infected-pig plasma medium at 18, 24, 36, and 48 h, after Ceftiofur Sodium inoculation. Pharmacokinetic parameters were combined with ex vivo pharmacodynamic parameters, and the bacteriostatic effect (36.006 h), bactericidal effect (71.637 h) and clearance (90.619 h) within 24 h, were determined using the Hill equation. Dose-calculation equations revealed the optimal dose of Ceftiofur Sodium to be 0.599–1.507 mg/kg. Conclusions There were no significant differences in Ceftiofur Sodium pharmacokinetic parameters between healthy and infected pigs, although pharmacokinetics/pharmacodynamics fitting curves showed obviously differences. The optimal dose of Ceftiofur Sodium was lower than recommended (3 mg/kg), which may provide improved treatments for Glässers disease, with lower drug-resistance possibility.

Interaction of 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX)/ammonium perchlorate (AP) and its effect on mechanical sensitivity may result in some restrictions for the application of AP/HMX system in high energetic weapon system. In this work, impact sensitivity test is used to study the effects of wax coating of HMX, AP and aluminum (Al) powder on sensitivity properties of HMX/AP/Al mixtures. Thermogravimetry-differential scanning calorimetry (TG-DSC) analysis has been developed to investigate the mechanism of interaction between HMX and AP during the course of thermal decomposition of HMX/AP/Al mixtures. The results show that severe interaction effect exists between AP and HMX, which causes the impact sensitivity (H50) to become smaller. The impact energy (E50) of mixture can be improved under the circumstances of effective separating HMX from AP by surface coating with Wax. AP may firstly engender low-temperature decomposition under the circumstance of external heat or mechanical impact, which causes the exothermic peak of HMX forward shift about 28 °C. The gaseous product releasing from thermal decomposition of HMX accelerates further decomposition of AP. For HMX/AP composite system, the interactive catalysis effect between AP and HMX can be eliminated mostly by adding a great deal of Al powder (i.e. above 30%).