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As the main equipment for earthquake disaster rescue and reconnaissance battlefield, the robustness of UAV swarm communication system is an important index of destruction resistance. In this paper, we model the UAV swarm communication system with the help of complex dependency network theory, introduce the relative network effectiveness ratio as an index of the overall robustness of the communication system network, which accurately reflects the interdependence between nodes, and provides a new perspective for evaluating the robustness of the communication system under the target attack. A new perspective is provided for assessing the robustness of communication systems under target attack. Based on the classical M-L model and the load redistribution strategy with dynamic information, we establish the dependent homogeneous ER-ER and heterogeneous ER-BA network models, consider the characteristics of the degree of dependent nodes in the two-layer network for target attack, and analyze the dynamic process of their cascading failure under the attack, as well as the influence of the characteristic parameters, such as the probability of connecting edges of any two nodes, the average degree and the capacity coefficient, on the overall robustness of the communication network. It is shown that network robustness and network dependency strength are negatively correlated, and a reduction of 52.09% to 72.9% dependency strength can be considered in the cascade failure process to resist more serious communication network collapse. For isomorphic networks, the difference in dependency patterns has a greater impact by reducing the overall robustness of RL and AL compared to DL by 9.25% and 15.95%, respectively.

前列腺素F2α（PGF2α）具有广泛的生理活性，是一种重要的脂质介质。为了实现PGF2α的绿色生物合成，构建了pET30a-TbPGFS、pET30a-MmPGHS、pET30a-GvPGHS载体并在大肠杆菌BL21（DE3）中分别表达，同时对异丙基-β-D-硫代半乳糖苷（IPTG）诱导表达条件进行了优化以提高重组蛋白在大肠杆菌中的表达量。另外，以最佳诱导表达条件下得到的重组蛋白为催化剂，催化花生四烯酸合成PGF2α。结果表明：MmPGHS蛋白在大肠杆菌中没有表达；GvPGHS蛋白的最佳诱导表达条件为诱导剂IPTG浓度0.2 mmol/L、诱导温度30 ℃、诱导时间2 h，TbPGFS蛋白的最佳诱导表达条件为诱导剂IPTG浓度0.2 mmol/L、诱导温度30 ℃、诱导时间6 h；在最佳诱导表达条件下，由GvPGHS和TbPGFS的粗酶液构成的双酶催化未能检测到产物PGF2α，而在酶偶联化学催化时，GvPGHS能将花生四烯酸转化为PGH2，PGH2被SnCl2进一步还原为PGF2α。综上，通过体外酶促反应结合化学法可高效转化花生四烯酸生产PGF2α。As the important lipid mediators, prostaglandin F2α（PGF2α）performs a wide range of physiological activities. To achieve the green biosynthesis of PGF2α, pET30a-TbPGFS, pET30a-MmPGHS and pET30a-GvPGHS vectors were constructed and expressed in Escherichia coli BL21 (DE3), respectively, and the induction expression conditions of isopropyl-β-D-thiogalactopyranoside (IPTG) were optimized to improve the expression of the recombinant protein in E.coli. In addition, the recombinant protein obtained under the optimal conditions were used as a catalyst to catalyze the synthesis of PGF2α from arachidonic acid. The results showed that MmPGHS protein was not expressed in E. coli. However, GvPGHS protein performed the optimized expression under the conditions of IPTG concentration 0.2 mmol/L, induction temperature 30 ℃ and induction time 2 h, the TbPGFS protein performed the optimized expression under the conditions of IPTG concentration 0.2 mmol/L, induction temperature 30 ℃ and induction time 6 h. Under the above optimized conditions, PGF2α was not detected by the two-enzyme coupled catalysis system composed of crude extract of GvPGHS and TbPGFS. However, arachidonic acid was converted into PGH2 by GvPGHS, which was further reduced to PGF2α by SnCl2 under the enzyme-coupled chemical catalysis. In conclusion, In vitro enzymatic reaction combined with chemical method can efficiently convert arachidonic acid to produce PGF2α.

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.

Repeated blood feedings are required for adult female mosquitoes to maintain their gonadotrophic cycles, enabling them to be important pathogen carriers of human diseases. Elucidating the molecular mechanism underlying developmental switches between these mosquito gonadotrophic cycles will provide valuable insight into mosquito reproduction and could aid in the identification of targets to disrupt these cycles, thereby reducing disease transmission. We report here that the transcription factor ecdysone-induced protein 93 (E93), previously implicated in insect metamorphic transitions, plays a key role in determining the gonadotrophic cyclicity in adult females of the major arboviral vector Aedes aegypti Expression of the E93 gene in mosquitoes is down-regulated by juvenile hormone (JH) and up-regulated by 20-hydroxyecdysone (20E). We find that E93 controls Hormone Receptor 3 (HR3), the transcription factor linked to the termination of reproductive cycles. Moreover, knockdown of E93 expression via RNAi impaired fat body autophagy, suggesting that E93 governs autophagy-induced termination of vitellogenesis. E93 RNAi silencing prior to the first gonadotrophic cycle affected normal progression of the second cycle. Finally, transcriptomic analysis showed a considerable E93-dependent decline in the expression of genes involved in translation and metabolism at the end of a reproductive cycle. In conclusion, our data demonstrate that E93 acts as a crucial factor in regulating reproductive cycle switches in adult female mosquitoes.

This paper summarizes the most recent development and progress of the open-pit mine autonomous haulage operation system in abroad and the development from scratch in domestic, and gives a brief introduction of the standardization work in the industry sector. On this basis, the key technical issues or the key requirements of open-pit mine autonomous haulage operation system is comprehensively described at systematical level,including nine core technical issues such as environment awareness and path planning,and five related technical issues such as line reconstruction and roadside monitoring. The system structure that satisfies the requirements is presented, consisting of ground management and supervision system, vehicle automation package onboard automated dumper, auxiliary operation package onboard collaborative machinery, data communication system and road side system. Eleven further research aspects including enhancement of automation grade, more comprehensive scenario description of event detection and response, as well as optimization of operation plan and regulation are proposed. The future of open-pit mine autonomous haulage operation system is prospected finally.

The high conductivity inherent to the dense graphite structures of carbon nanofibers (CNFs) results in microwave reflection, making it a noteworthy topic to design structures that endow CNFs with microwave absorption capabilities. Herein, drawing inspiration from Sun Tzu's strategy of luring the enemy deep, a novel tree-like heterostructure of CNFs (co-CPAN@PVP) was designed using coaxial electrospinning and a subsequent carbonization process. The shell layer consists of a blend of polyacrylonitrile (PAN-2) and polyvinylpyrrolidone (PVP), serving as the bark of the tree, while the core layer, namely the trunk, is made of polyacrylonitrile (PAN-1). During the high-temperature carbonization, the heterostructures of the "bark" result in the formation of non-uniform carbon structures on the fiber surface, creating channels that are easily penetrated by microwaves, which act as enemies. The conductive pathways formed by the carbon structure of the "trunk", in conjunction with the polarization sites of the "bark", facilitate microwave attenuation. The results show that co-CPAN@PVP with heterostructures has good impedance matching characteristics and microwave attenuation ability. The minimum reflection loss (RLmin) at 1.8 mm is −55.19 dB, and the effective absorption bandwidth (EAB) is 5.695 GHz. This research has inspired the design of heterostructures for high-performance and lightweight carbon-based microwave absorbing materials (MAMs). Moreover, it introduces a solution for recycling and reusing waste electromagnetic and thermal energy, potentially mitigating pressing environmental and energy challenges. [ABSTRACT FROM AUTHOR]

Radar work mode recognition is crucial to analyse radar behaviour and intention. There are some challenges limiting the recognition of long sequences with multiple mode classes. First, the performance of recognition method relies on precise segregation of intercepted sequence, which is often unfeasible in reality. Second, the states at the boundaries of adjacent modes may create extraneous mode samples that intervenes the recognition. Third, current methods fail to deal with the scenarios where multiple modes share the same state sequence. To address these problems, a novel forward matching method (FMM) is proposed, comprising a shortest path method (SPM) for intra‐mode recognition, a matching strategy, and an adjustment mechanism. SPM is to provide potential recognition for short fragments of the given long sequence. The matching strategy is to assess the availability of current recognition. The adjustment mechanism tunes the segregation and improves the subsequent recognition. FMM offers several distinct advantages. First, the model can explicitly characterise the mode transition probability and is totally interpretable. Second, FMM can distinguish intentional ambiguities, alleviate mosaic ambiguity and probability deviation associated with inter‐mode recognition. Third, FMM is extendable to integrate with other intro‐mode recognition methods to cater to various scenarios. [ABSTRACT FROM AUTHOR]

Hedera helix is a traditional medicinal plant. Its primary active ingredients are oleanane-type saponins, which have extensive pharmacological effects such as gastric mucosal protection, autophagy regulation actions, and antiviral properties. However, the glycosylation-modifying enzymes responsible for catalyzing oleanane-type saponin biosynthesis remain unidentified. Through transcriptome, cluster analysis, and PSPG structural domain, this study preliminarily screened four candidate UDP-glycosyltransferases (UGTs), including Unigene26859, Unigene31717, CL11391.Contig2, and CL144.Contig9. In in vitro enzymatic reactions, it has been observed that Unigene26859 (HhUGT74AG11) has the ability to facilitate the conversion of oleanolic acid, resulting in the production of oleanolic acid 28-O-glucopyranosyl ester. Moreover, HhUGT74AG11 exhibits extensive substrate hybridity and specific stereoselectivity and can transfer glycosyl donors to the C-28 site of various oleanane-type triterpenoids (hederagenin and calenduloside E) and the C-7 site of flavonoids (tectorigenin). Cluster analysis found that HhUGT74AG11 is clustered together with functionally identified genes AeUGT74AG6, CaUGT74AG2, and PgUGT74AE2, further verifying the possible reason for HhUGT74AG11 catalyzing substrate generalization. In this study, a novel glycosyltransferase, HhUGT74AG11, was characterized that plays a role in oleanane-type saponins biosynthesis in H. helix, providing a theoretical basis for the production of rare and valuable triterpenoid saponins. [ABSTRACT FROM AUTHOR]