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Despite the extensive body of literature on the correlation between family dynamics and academic achievement among students, there remains a notable gap in research investigating the influence of parental educational involvement on student learning engagement. Based on the developmental–ecological model of student engagement and relevant theoretical frameworks, this study used the quantitative analysis method to construct a chain mediation model to test the relationship between parental educational involvement and the learning engagement of middle school students, as well as the potential mediating role of gratitude and hope. This study employed a cross-sectional study using whole-cluster random sampling to measure middle school students aged 11–18 years old in two schools over a one-week period. Through the use of self-reporting surveys, this study assessed the levels of parental educational involvement, gratitude, hope, and learning engagement among 754 middle school students (48% female; Mage = 14.83, SD = 1.65) in Hubei Province, China. The mediation effect was analyzed using regression analysis and the chained mediation model and tested via the Bootstrap method. The findings suggested that parental educational involvement significantly positively related to learning engagement among middle school students, while gratitude and hope serve as partial mediators in the relationship between parental educational involvement and learning engagement. These findings revealed the psychological mechanisms underlying the relationship between parental educational involvement and learning engagement among middle school students, providing valuable insights for enhancing their level of learning engagement. [ABSTRACT FROM AUTHOR]

With the rapid growth of wireless nodes numbers and the increase in demanding for high-bandwidth transmission services such as multimedia images, the related fields of the agricultural Internet of Things(IoT) can foresee a trend of shortage of wireless spectrum resources. For the crop phenotypic information collection system based on the traditional IoT, there are many problems such as spectrum competition, data congestion during the data transmission process due to the dense deployment of nodes, and the reduction of the monitoring cycle due to uneven energy consumption in the fixed battery network. Based on previous studies, a crop phenotypic information collection model for cognitive radio sensor networks was established, and based on the model, an event-driven clustering routing algorithm that introduced dynamic spectrum and energy balance (DSEB) of edge computer system was proposed. The algorithm includes dynamic spectrum sensing clustering. The hierarchical clustering algorithm was used to combine the available channels, distances between nodes, residual energy, and neighbor node degrees obtained by spectrum sensing as similarities to cluster and cluster nodes in the monitored area and select cluster heads. The process of clustering and selecting cluster heads and constructing a clustering topology introduceed rewards and punishment factors to the equilibrium of the clustering sizes to improve the average spectrum utilization of each clustering network. The events triggered by edge computing trigger data routing, and based on the clustered topology structure, the events triggered by abnormal changes in farm conditions in the areas to be detected on the farm were forwarded to the convergent nodes by means of alternate cluster iterations and inter-cluster relays. Convergence includes direct transmission and intra-cluster relay, and inter-cluster relay includes two cases: ①primary gateway node and secondary gateway node-primary gateway node; ②adaptive re-clustering based on spectrum changes and communication quality of service (QoS)－changes in available channels caused by changes in the PU behavior of the primary user, or interference with poor quality of clustering effects on communication service quality, triggering cognitive radio sensor networks to perform adaptive re-clustering. In addition, a new energy balancing strategy was proposed to decentralize energy consumption (assuming sink is the center), that is, introducing a weight coefficient proportional to the distance from the node to the sink in the gateway or cluster head node selection calculation formula. The simulation results of the algorithm showed that, compared with the event-driven clustering ERP routing scheme using K-medoid clustering and energy sensing, under the premise that the number of CRSN nodes is a fixed value, the clustering routing algorithm based on DSEB in the network lifetime and there are certain improvements in utilization and energy efficiency; when the number of primary user nodes is a fixed value, the proposed algorithm has higher spectrum utilization than the other two algorithms.

Immobilized metal ion affinity chromatography (IMAC) adsorbents generally have excellent affinity for histidine-rich proteins. However, the leaching of metal ions from the adsorbent usually affects its adsorption performance, which greatly affects the reusable performance of the adsorbent, resulting in many limitations in practical applications. Herein, a novel IMAC adsorbent, i.e., Cu(II)-loaded polydopamine-coated urchin-like titanate microspheres (Cu-PDA-UTMS), was prepared via metal coordination to make Cu ions uniformly decorate polydopamine-coated titanate microspheres. The as-synthesized microspheres exhibit an urchin-like structure, providing more binding sites for hemoglobin. Cu-PDA-UTMS exhibit favorable selectivity for hemoglobin adsorption and have a desirable adsorption capacity towards hemoglobin up to 2704.6 mg g−1. Using 0.1% CTAB as eluent, the adsorbed hemoglobin was easily eluted with a recovery rate of 86.8%. In addition, Cu-PDA-UTMS shows good reusability up to six cycles. In the end, the adsorption properties by Cu-PDA-UTMS towards hemoglobin from human blood samples were analyzed by SDS-PAGE. The results showed that Cu-PDA-UTMS are a high-performance IMAC adsorbent for hemoglobin separation, which provides a new method for the effective separation and purification of hemoglobin from complex biological samples. [ABSTRACT FROM AUTHOR]

This paper introduces the SIS epidemic model into a production-based economy. We study the asset pricing implications of the interaction between COVID-19's shock and mitigation policy for the production economy. The mitigation policy could hinder the consumption, while it will prompt an investment slump. The results indicate some trade-offs between mitigating the transmission of the pandemic and economic output varying with different uncertainty of the pandemic. Notably, the risk premium and growth of capital value present an inverse hump-shape with the infection rate. [ABSTRACT FROM AUTHOR]

Island endemic birds account for the majority of extinct vertebrates in the past few centuries. To date, the evolutionary characteristics of island endemic bird's is poorly known. In this research, we de novo assembled a high‐quality chromosome‐level reference genome for the Swinhoe's pheasant, which is a typical endemic island bird. Results of collinearity tests suggest rapid ancient chromosome rearrangement that may have contributed to the initial species radiation within Phasianidae, and a role for the insertions of CR1 transposable elements in rearranging chromosomes in Phasianidae. During the evolution of the Swinhoe's pheasant, natural selection positively selected genes involved in fecundity and body size functions, at both the species and population levels, which reflect genetic variation associated with island adaptation. We further tested for variation in population genomic traits between the Swinhoe's pheasant and its phylogenetically closely related mainland relative the silver pheasant, and found higher levels of genetic drift and inbreeding in the Swinhoe's pheasant genome. Divergent demographic histories of insular and mainland bird species during the last glacial period may reflect the differing impact of insular and continental climates on the evolution of species. Our research interprets the natural history and population genetic characteristics of the insular endemic bird the Swinhoe's pheasant, at a genome‐wide scale, provides a broader perspective on insular speciation, and adaptive evolution and contributes to the genetic conservation of island endemic birds. [ABSTRACT FROM AUTHOR]

According to the mechanical characteristics of the terrain of sea bed cobalt crusts and hydrothermal sulfide mining,based on the traditional road tracked vehicle,a solid wheels-rubber tracked traveling mechanism in deep sea bed is designed. The dynamics modeling of tracked traveling mechanism in deep sea bed is built based on the structural characteristics. In dealing with the engaging force,the application of elastic contact theory,the meshing force is equivalent to the force of the resilient contact. The driving force mechanism is analyzed and the influencing factors are analyzed. Based on Recurdyn,the simplified dynamics model of the traveling mechanism in deep sea bed is built,imposing constraints,contacts,forces and motion control functions,and the terrain and environmental conditions in different types when run under the sea bed are analyzed.The results show that,the engaging force between solid wheel and track pin changes with the positive pressure changes,the positive pressure occurs the maximum and corresponding to the maximum of engaging force,then the positive pressure and engagement force is cyclical change along with the caterpillar. Meanwhile,a greater ripple of the speed,running gear,acceleration,driving torque and so on is caused by the tracked speed dynamic load. However,the tracked traveling mechanism is still running driven relatively stable.