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Abstract P2X receptors, a subfamily of ligand-gated ion channels activated by extracellular ATP, are implicated in various physiopathological processes, including inflammation, pain perception, and immune and respiratory regulations. Structural determinations using crystallography and cryo-EM have revealed that the extracellular three-dimensional architectures of different P2X subtypes across various species are remarkably identical, greatly advancing our understanding of P2X activation mechanisms. However, structural studies yield paradoxical architectures of the intracellular domain (ICD) of different subtypes (e.g., P2X3 and P2X7) at the apo state, and the role of the ICD in P2X functional regulation remains unclear. Here, we propose that the P2X3 receptor’s ICD has an apo state conformation similar to the open state but with a less tense architecture, containing allosteric sites that influence P2X3’s physiological and pathological roles. Using covalent occupancy, engineered disulfide bonds and voltage-clamp fluorometry, we suggested that the ICD can undergo coordinated motions with the transmembrane domain of P2X3, thereby facilitating channel activation. Additionally, we identified a novel P2X3 enhancer, PSFL77, and uncovered its potential allosteric site located in the 1α3β domain of the ICD. PSFL77 modulated pain perception in P2rx3 +/+, but not in P2rx3 −/−, mice, indicating that the 1α3β, a “tunable” region implicated in the regulation of P2X3 functions. Thus, when P2X3 is in its apo state, its ICD architecture is fairly ordered rather than an unstructured outward folding, enabling allosteric modulation of the signaling of P2X3 receptors.

With thermoplastic polyurethane (TPU) limit spring extruder head as the research object, the relevant material parameters of the constitutive equation of raw TPU were obtained by the rheological property test. Numerical simulation of the flow process of TPU in the extrusion runner was carried out based on the software Polyflow, and in the meanwhile, a second-order regression model of standard deviation of velocity (Sd) at the exit of the forming section was established by response surface method, and the influence law of extrusion runner structure on the melt flow uniformity of TPU was explored. The results showed that after optimization the structure parameters of extrusion runner were as follows: the length of the forming section of 165 mm, the expansion angle of 25°, and the number of diverter shuttles of 6. After optimization the predicted value of Sd at the exit of the forming section of extrusion runner was 0.531 m/s and was only 0.188% different from the actual value of Sd(0.532 m/s), which indicated that the model was more accurate, and the model could be used for the prediction and optimization of the structure parameters of extrusion runner.

Genetic algorithm (GA) and particle swarm optimization (PSO) were used to optimize the back propagation（BP） neural network to establish the prediction model of Mooney viscosity of ethylene-propylene-diene monomer (EPDM) compound, and the error of the prediction results was compared and analyzed. The results showed that the predicted va-lues of the BP neural network model optimized by the two algorithms all maintained a high degree of fit and correlation with the measured values. Compared with the single BP neural network, the accuracy of the GA-BP neural network prediction model increased by 58.9% and the accuracy of the PSO-BP model increased by 3.57%, which indicated that the prediction accuracy of the prediction model optimized by the two algorithms, especially the BP neural network prediction model optimized by GA, improved significantly Mooney viscosity of EPDM compound.

Abstract Background The parallel evolution of similar traits or species provides strong evidence for the role of natural selection in evolution. Traits or species that evolved repeatedly can be driven by separate de novo mutations or interspecific gene flow. Although parallel evolution has been reported in many studies, documented cases of parallel evolution caused by gene flow are scarce by comparison. Aquilegia ecalcarata and A. kansuensis belong to the genus of Aquilegia, and are the closest related sister species. Mutiple origins of A. ecalcarata have been reported in previous studies, but whether they have been driven by separate de novo mutations or gene flow remains unclear. Results In this study, We conducted genomic analysis from 158 individuals of two repeatedly evolving pairs of A. ecalcarata and A. kansuensis. All samples were divided into two distinct clades with obvious geographical distribution based on phylogeny and population structure. Demographic modeling revealed that the origin of the A. ecalcarata in the Eastern of China was caused by gene flow, and the Eastern A. ecalcarata occurred following introgression from Western A. ecalcarata population. Analysis of Treemix and D-statistic also revealed that a strong signal of gene flow was detected from Western A. ecalcarata to Eastern A. ecalcarata. Genetic divergence and selective sweep analyses inferred parallel regions of genomic divergence and identified many candidate genes associated with ecologically adaptive divergence between species pair. Comparative analysis of parallel diverged regions and gene introgression confirms that gene flow contributed to the parallel evolution of A. ecalcarata. Conclusions Our results further confirmed the multiple origins of A. ecalcarata and highlighted the roles of gene flow. These findings provide new evidence for parallel origin after hybridization as well as insights into the ecological adaptation mechanisms underlying the parallel origins of species.

[Objective] Methanol, a renewable and green fuel, holds significant potential for broad applications. However, its long-distance pipeline transmission technology remains underutilized in practical scenarios. [Methods] This study investigated the feasibility and existing challenges of long-distance methanol pipeline transmission technology. Through a comprehensive examination of cases involving methanol transmission pipelines in China and abroad, this research reviewed process and equipment requirements, while analyzing potential safety risks during transmission. The study also assessed the current development status of industrial standards and specifications in this field and highlighted the challenges hindering the widespread adoption of this technology. Additionally, future development trends were anticipated based on the study results. [Results] This study not only highlighted the promising application prospects of methanol as a green fuel in long-distance pipeline transmission but also unveiled the challenges faced in its implementation. Specific focus was given to system design requirements to accommodate the unique physical and chemical characteristics of methanol, such as flow rate control and equipment selection. Safety risks, including corrosion, swelling, leakage, and explosion, were also emphasized. Moreover, the study stressed the need for overall improvement in technology standards and specifications due to the limited number of practical methanol transmission cases. [Conclusion] To achieve the commercialization and large-scale implementation of methanol pipeline transmission technology, it is essential to tackle technical and safety challenges systematically. Key considerations include enhancing methanol purity, optimizing the transmission process,and selecting suitable corrosion-resistant and swelling-resistant materials.Besides,it is also imperative to establish comprehensive safety standards and emergency response strategies.This study recommends strengthening fundamental scientific research,fostering technological innovation,and establishing robust management systems and policy frameworks to ensure safe operations,economic benefits,and environmental sustainability in methanol transportation technology applications.

Given the impact of anxiety on foreign language reading, understanding how English as a Foreign Language (EFL) reading anxiety is evoked would help teachers facilitate their students in the reading process effectively. This study aimed at investigating the sources of EFL reading anxiety of Chinese university students. The data were collected from 459 non-English major students from four different universities in China, using an adapted version of English as a Foreign Language Reading Anxiety Inventory (EFLRAI) developed by Zoghi (2012). The findings showed that the participants experienced the moderate level of EFL reading anxiety overall and also categorically. The main source of anxiety was from the lack of general reading ability. Of the three key factors that seemed to arouse higher levels of anxiety than the others, one related to the general reading ability and the other two were vocabulary-related factors. Chinese university students tended to read for details and seemed to get highly anxious when they did not understand 'everything'. These findings lend suggestions to some interventions that English teachers may use to reduce Chinese university students' anxiety when reading.

Objective: To solve the problem of unstable rice output quality caused by the lack of information exchange and coordinated control between equipment in the rice processing system. Methods: Based on the industrial internet of things technology, a five-layer architecture of the rice processing system was constructed, and the solutions to the technical problems existing in the network layer, decision layer and control layer of the architecture were proposed for the corresponding layer problems such as the wireless sensor network model based on machine vision, the fuzzy self-tuning control model based on differential evolutionary algorithm and the rubber roller synchronization control method of the huller. The hardware and software of the system were designed, the actual transformation of the hulling and milling section was carried out, and then early indica rice grains were selected for processing tests. Results: Compared with the traditional processing, the improved rice processing system increased the browning rate about 1%, the whole fine rice rate by about 1%, and the production energy consumption is reduced about 15%. Conclusion: The researched rice processing system based on IOT technology has implications for improving the intelligent transformation of process processing systems such as rice processing.