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The bird cherry‐oat aphid (Rhopalosiphum padi) and the grain aphid (Sitobion miscanthi) are two destructive wheat pests that have caused severe economic losses in China's main wheat‐producing regions. Although previous studies have focused mainly on the population dynamics of wheat pests in wheat fields, little is known about the trans‐sea migration of both wheat aphid species in eastern China. Here, we conducted 10 years of monitoring from 2012 to 2021 to determine aerial migration patterns utilizing a suction trap on Beihuang Island (BH), a small island in the centre of the Bohai Strait that serves as a seasonal insect migratory pathway in eastern Asia. We also simulated the migration trajectories of these pests using the HYSPLIT model. Overall, a total of 6362 alatae S. miscanthi and 335 alatae R. padi were captured, and both wheat aphid species exhibited regular patterns of comigration across the sea from late April to late October each year. There were significant interannual and seasonal differences in the migratory numbers of both wheat aphids. Notably, the average daily humidity was the most important meteorological factor affecting migration biomass. The seasonal migration trajectories simulated using the HYSPLIT model revealed different source areas for both wheat aphid species, which mostly originated in Northeast, North and East China. Accordingly, our study provides valuable insights into the occurrence and migration route of wheat aphids in eastern Asia, helps fine‐tune forecasting and early warning systems, and thereby guides integrated pest management of wheat aphids in eastern Asia. [ABSTRACT FROM AUTHOR]

In order to weaken the torque ripple caused by cogs torque and increase the output torque of permanent magnet synchronous motor, this paper proposes a multi-objective optimization method of permanent magnet synchronous motor based on Improved Multi-Objective Salp Swarm Optimization Algorithm (IMOSSA) and Spearman correlation analysis. Firstly, the improved strategy of Multi-Objective Salp Swarm Algorithm (MOSSA) was proposed, and the effectiveness of the improved algorithm was further verified by the performance test of the algorithm. Then, the motor simulation model was established, and the high correlation parameters were filtered out by Spearman correlation analysis. The response surface model was established by Response Surface Method (RSM), and the regression equation was given. The IMOSSA was used for iterative optimization. Through optimization, the experimental results show that under the premise of meeting the efficiency design requirements, the average output torque of the motor is increased by 21.35%, the torque ripple and cogging torque are reduced by 45.04% and 39.17% respectively, which verifies the effectiveness and feasibility of the proposed method. [ABSTRACT FROM AUTHOR]

In this study, a predictive model is constructed to analyze learners' performance in programming tasks using data of programming behavioral events and behavioral sequences. First, this study identifies behavioral events from log data and applies lag sequence analysis to extract behavioral sequences that reflect learners' programming strategies. Then, learners' behavioral events and behavioral sequences are selected using linear regression. Finally, a predictive model is built using majority vote. The study uses data from 3151 programming tasks to compare the accuracy of predictive models with and without behavioral sequences. The results show that the accuracy of the predictive model with behavioral sequences is 75.75%, which is 2.06% higher than that of the model without behavioral sequences. This study finds that editing, debugging, and self-regulating behavior sequences can reflect the strategies learners employ during programming. These findings underscore that the model based on behavioral events and behavioral sequences in this study can successfully predict learners' programming performance and thereby has the potential to support programming instruction. [ABSTRACT FROM AUTHOR]

Simple Summary: Green lacewing is an important natural predator of many crop pests. In this study, we conducted 10 years of monitoring from 2012 to 2021 to determine the aerial migration patterns of green lacewing species using a suction trap on Beihuang Island (BH), a small island in the center of the Bohai Strait that serves as a seasonal insect migration pathway in eastern Asia. Overall, there were significant interannual and seasonal differences in the densities of the main species, and the sex ratio varied among different months, with more females being captured than males. It was determined that the green lacewings primarily originated from Shandong Province through trajectory analysis. This study provides valuable insights into the migration dynamics of green lacewings in eastern Asia, which is helpful for biological control in the region. Many insects, including green lacewings, migrate seasonally to exploit suitable breeding and winter habitats. Green lacewings are important natural enemies of insect pests worldwide. Here, four dominant green lacewing species, Chrysoperla nipponensis (Okamoto), Chrysopa pallens (Rambur), Chrysoperla furcifera (Okamoto), and Chrysopa formosa Brauer, were investigated for their ability to migrate between northern and northeastern China across the Bohai Strait from late May to late October each year. Furthermore, there were significant interannual and seasonal differences in the number of migratory green lacewings collected. The number of green lacewings in spring was significantly lower than that in summer and autumn, and the highest average number of green lacewings occurred in June. In addition, there were differences in the sex ratio of migrating green lacewings between months, with a greater proportion of females than males. Finally, the seasonal migration trajectories simulated by the HYSPLIT model revealed that the green lacewings captured on Beihuang Island primarily originated from Shandong Province. Accordingly, these findings contribute to our understanding of green lacewing migration in eastern Asia and aid its incorporation within integrated pest management (IPM) packages for several crop pests. Furthermore, long-term tracking of migrant insect populations can reveal ecosystem services and trophic dynamic processes at the macroscale. [ABSTRACT FROM AUTHOR]

Circularly polarized luminescence (CPL) plays a pivotal role in cutting‐edge display and information technologies. Currently achieving precise color control and dynamic signal regulation in CPL still remains challenging due to the elusory relationship between fluorescence and chirality. Inspired by the natural mechanisms governing color formation and chiral interaction, we proposed an addition‐subtraction principle theory to address this issue. Three fluorene‐based polymers synthesized by Suzuki polycondensation with different electron‐deficient monomers exhibit similar structures and UV/Vis absorption, but distinct fluorescence emissions due to intramolecular charge transfer. Based on this, precise‐color CPL‐active films are obtained through quantitative supramolecular co‐assembly directed by addition principle. Particularly, an ideal white‐emitting CPL film (CIE coordinates: (0.33, 0.33)) is facilely fabricated with a high quantum yield of 80.8 % and a dissymmetry factor (glum) of 1.4×10−2. Structural analysis reveals that the ordered stacking orientation favors higher glum. Furthermore, to address the dynamically regulated challenge, the comparable subtraction principle is proposed, involving a contactless chiral communication between excited and ground states. The representative system consisting of as‐prepared fluorene‐based polymers and chirality‐selective absorption azobenzene (Azo)‐containing polymers is constructed, achieving CPL weakening, reversal, and enhancement. Finally, a switchable quick response code is realized based on trans‐cis isomerization of Azo moiety. [ABSTRACT FROM AUTHOR]

New insights are raised to interpret pathway complexity in the supramolecular assembly of chiral triarylamine tris‐amide (TATA) monomer. In cosolvent systems, the monomer undergoes entirely different assembly processes depending on the chemical feature of the two solvents. Specifically, 1,2‐dichloroethane (DCE) and methylcyclohexane (MCH) cosolvent trigger the cooperative growth of monomers with M helical arrangement, and hierarchical thin nanobelts are further formed. But in DCE and hexane (HE) combination, a different pathway occurs where monomers go through isodesmic growth to generate twisted nanofibers with P helical arrangement. Moreover, the two distinct assemblies exhibit opposite excited‐state chirality. The driving force for both assemblies is the formation of intermolecular hydrogen bonds between amide moieties. However, the mechanistic investigation indicates that radical and neutral triarylamine species go through distinct assembly phases by changing solvent structures. The neutralization of radicals in MCH plays a critical role in pathway complexity, which significantly impacts the overall supramolecular assembly process, giving rise to inversed supramolecular helicity and distinct morphologies. This differentiation in pathways affected by radicals provides a new approach to manipulate chiral supramolecular assembly process by facile solvent–solute interactions. [ABSTRACT FROM AUTHOR]

A synthetic flocculant of aluminum (Al) and iron (Fe) extracted from red mud (RM) has been widely used in sewage treatment, while the remaining RM residue has been ignored. This study aimed to synthesize polymeric aluminum ferric sulfate (PAFS) flocculant from RM by acid leaching and then use the acidified RM residue to produce an acid RM-based ceramsite (ARMC) by mixing bentonite, hydroxypropyl methylcellulose, and starch. Our results showed that sintering, reaction temperature, H2SO4 concentration, reaction time, and liquid-to-solid ratio had an obvious effect on the leaching of Al and Fe in RM, which was a necessary prerequisite for the efficient PAFS flocculants. At a PAFS dosage of 60 mg/L, turbidity and phosphate removal rates were 95.21 ± 0.64% and 89.17 ± 0.52%, respectively. When the pH value was 8.0, the turbidity and phosphate removal efficiency were 99.22 ± 0.66% and 95.98 ± 1.63%, respectively. Considering the adsorption capacity and mechanical properties, the best conditions for ARMC production included using 60% ARM and ceramsite calcination at 600 °C, with the BET surface area 56.16 m2/g and a pore volume of 0.167 cm3/g. Thermogravimetric analysis indicated that 400 °C was a reasonable preheating temperature to enhance the ARMC mechanical strength, as this temperature allows the removal of surface-adsorbed and constituent water. Under a scanning electron microscope, the ARMC appeared rough before adsorption, while relatively uniform pores occupied it after adsorption. Our conclusion will help to improve the zero-waste strategy of RM and speed up the industrial production of RM in flocculants as well as utilizing ARMC as a new type of adsorbent for phosphorus adsorption in sewage treatment. [ABSTRACT FROM AUTHOR]

The white back planthopper (WBPH), Sogatella furcifera (Horváth) (Hemiptera: Delphacidae), is an important destructive rice pest in Asia that has caused serious economic losses in the main rice‐producing areas of China. To effectively manage this rice pest, it is necessary to investigate its genetic variation and genetic structure and speculate the migration route in China. In this study, we used 12 nuclear microsatellite loci to analyse the genetic variation, gene flow and genetic structure of WBPH in 25 geographic populations in China. Overall, high levels of genetic diversity and genetic differentiation among most populations were detected. Neighbour‐joining dendrograms, STRUCTURE and principal coordinate analysis (PCoA) revealed three genetically distinct groups and exhibited an admixed phylogeographic structure. There was a significant low positive correlation between genetic and geographic distances (r2 = 0.105, p = 0.001), which indicated the role of geographic isolation in the genetic structure of WBPH. Migrant routes detection indicated frequent gene flow exchange between North China and Central China, and low bidirectional gene flows between Northeast China and other regions were detected. Accordingly, this study provides useful data for resolving the genetic relationships and large‐scale migration route of the WBPH and thus contributes to developing more effective management strategies for controlling this pest. [ABSTRACT FROM AUTHOR]

With the development of new energy sources and the increase in the installed scale of energy coupling equipment, the low-carbon transformation of the energy supply of the integrated energy system (IES) has a serious impact on the reliability of the IES supply, and there is an urgent need for a reasonable and accurate assessment and trade-off between the IES resilience and economics. In this regard, this paper models the overall optimization of the resilience and economic configuration and operation scheduling of the IES in the islanded operation mode after grid faults, proposes a two-layer optimization strategy model of resilience and economy, and solves the unit configuration, coupled output characteristics, and optimal scheduling of the islanded IES using the Markov decision-making process and forbearing stratified sequencing method, and evaluates and analyzes the resilience and cost of the various types of IES configuration schemes. Resilience and cost are also evaluated and analyzed. Finally, an example analysis is carried out in an electric-heat-cooling integrated energy system. The results show that the proposed two-tier optimization strategy model can optimize the IES configuration scheme and coordinate the scheduling of each equipment, and the overall annualized cost of the energy system decreases by CNY 45.21 thousand, or a percentage decrease of 5.24%, compared to the same configuration of the conventional strategy. The typical day toughness index improved by 7.33%, 7.56%, and 13.01% in the spring, summer, and autumn, respectively. [ABSTRACT FROM AUTHOR]