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Echovirus 11 (E11) has gained attention owing to its association with severe neonatal infections. From 2018 to 2023, a surge in severe neonatal cases and fatalities linked to a novel variant of genotype D5 was documented in China, France, and Italy. However, the prevention and control of E11 variants have been hampered by limited background data on the virus circulation and genetic variance. Therefore, the present study investigated the circulating dynamics of E11 and the genetic variation and molecular evolution of genotype D5 through the collection of strains from the national acute flaccid paralysis (AFP) and hand, foot, and mouth disease (HFMD) surveillance system in China during 2000–2022 and genetic sequences published in the GenBank database. The results of this study revealed a prevalent dynamic of E11 circulation, with D5 being the predominant genotype worldwide. Further phylogenetic analysis of genotype D5 indicated that it could be subdivided into three important geographic clusters (D5-CHN1: 2014–2019, D5-CHN2: 2016–2022, and D5-EUR: 2022–2023). Additionally, variant-specific (144) amino acid mutation sites and positive-selection pressure sites (132, 262) were identified in the VP1 region. Cluster-specific recombination patterns were also identified, with CVB5, E6, and CVB4 as the major recombinant viruses. These findings provide a preliminary landscape of E11 circulation worldwide and basic scientific data for further study of the pathogenicity of E11 variants.

Besides improving students' understanding of scientific concepts, chemistry teaching should also improve students' ability of applying concepts to solve problems. The research aims to explore the effects of modeling teaching on students' proficiency in solving galvanic cell problems. This research used a quasi-experimental design, and the independent variable of the research was the teaching method. Forty-five students in the experimental class received modeling teaching, and 48 students in the control class received lecture-style teaching. The dependent variable was the performance level of the student's ability to solve the problem of the galvanic cell, which was evaluated using the galvanic cell proficiency assessment tool. The research results show that the students in the experimental class were significantly more proficient in solving galvanic cell problems than those in the control class. The results of unstructured interviews assisted in illustrating the role of modeling teaching in improving the proficiency of students in solving galvanic cell problems, and students in the experimental class had positive views on modeling teaching.

The electromagnetic servo steering gear commonly used in the modern small guided aircraft has parasitic electromagnetic fields that affect the navigation and guidance accuracy, and its deceleration mechanism will increase the volume and mass, and the operating temperature range of the electromagnetic steering gear is small. A recently developed piezoelectric linear displacement accumulating high-power density actuator can solve those problems effectively. A virtual prototype model of piezoelectric linear displacement accumulating high-power density actuator is established, and the reliability of the virtual prototype model is verified by comparing with the experimental data. In order to make the actuator with the lightest weight under the requirements of wing deployment, Isight and Adams co-simulation were used to optimize the parameters of the piezoelectric actuator, such as the outer diameter, length, and excitation frequency. Finally, the output power of 50.8 W/kg is achieved, which is comparable with the power density of the existing servo motor.

Hand, foot, and mouth disease (HFMD), a common childhood infection caused by enterovirus, poses a serious public health concern in China. We collected and analyzed epidemiological data on 62,133 HFMD cases in Shenyang City, Liaoning Province, from 2013 to 2023. The average annual incidence was 76.12 per 100,000 person-years; 99.45% of cases were mild, while 0.55% were severe. Only one patient died. HFMD infections peaked annually in July. Children in kindergartens and scattered children accounted for 44.6% and 42.2% of cases, respectively. Real-time RT-PCR detection of enteroviruses in 5534 patient samples revealed 3780 positives, of which 25.1% were CVA16-positive. Positives were randomly sampled, yielding 240 VP1 sequences of CVA16. Phylogenetic tree results showed that all VP1 sequences belonged to the B1 sub-genogroup. However, the sub-genogroup prevalence varied over time: from 2013 to 2014 and 2019 to 2021, the predominant sub-genogroup was B1a, while it was B1b from 2015 to 2018. Further phylogenetic analyses showed substantial divergence between B1a branches in CVA16, suggesting possible turnover of the B1a sub-genogroup in CVA16 due to evolution. This study provides epidemiological data on HFMD in Shenyang, and provides a phylogenetic analysis of CVA16, offering a theoretical basis for preventing and controlling HFMD in Shenyang City. [ABSTRACT FROM AUTHOR]

The galvanic cell is a basic concept in electrochemistry. To assess mainland Chinese students' proficiency levels in galvanic cells, the Galvanic Cell Proficiency Level Assessment (GCPA) was developed based on the Rasch model. The GCPA was developed through a pilot test and consists of seven multiple-choice questions and four open questions. The assessment instrument was administered to 621 high school students in the 11th grade, and the test results showed good reliability and validity. The interview results supported the validity of the data generated by the instrument.

In this study, biomass-derived carbon quantum dots (CQDs) were synthesized by an one-step hydrothermal method using folium cycas as a carbon source. By optimizing the reaction conditions, the fluorescence quantum yield of CQDs was obtained to be as high as 8.91%, and strong blue emission light was emitted. The characterization results showed that the CQDs were quasi-spherical with an average particle size of 2.69 ± 0.08 nm and contained a large number of hydrophilic functional groups with excellent water solubility and photostability. The CQDs showed high selectivity and sensitivity for the detection of Fe3+, with a low limit of detection of 0.72 μM and a wide linear range of 0–200 μM. The practical applicability of the CQDs was further established by carrying out Fe3+ detection in environmental sample analysis. Besides, CQDs have been successfully applied to in vitro cell imaging and bioimaging. The final by-product of the hydrothermal reaction, biochar, is used for dye adsorption. This work identifies the importance of using a relatively green process and an inexpensive biomass precursor to produce high-quality CQDs that hold a promising future for use in metal ion detection, bioimaging, and practical sensing applications. [ABSTRACT FROM AUTHOR]

To understand the role of Apis cerana cerana in olive tree (Olea europaea L.) pollination, pollinators and pollen carried by bees were collected from 11 experimental plots during the flowering period. The abundance and diversity of pollen plant species were investigated using DNA metabarcoding. A total of 583 pollinators were collected and A. cerana cerana accounts for 46.83%. Further analysis revealed a total of 56 families, 136 genera and 195 plant species in bee pollens. O. europaea is the dominant species accounting for 42.02 ± 34.89% and then followed by Sedum japonicum (8.70 ± 16.42%). Diversity index showed that the abundance and diversity of pollen plant species were the highest in Wanzhou (WZ) and lowest in Hechuan (HC). This suggests that Wanzhou sample plot has a greater abundance of plant species to supplement the bee diet. Excessive presence of miscellaneous flowering plants in olive plantations can distract bees from collecting olive tree pollens. Therefore, their abundances can be reduced appropriately while ensuring food diversity for the bees. Based on the abundance of plants in pollens, we recommend that appropriately planting of S. japonicum, Youngia japonica and Vicia villosa in olive plantations with fewer flowering plants could be an effective supplement of bee food. Our results not only contribute to future studies on olive tree pollination but also provide new ideas for enriching flowering plants in or around olive plantations. [ABSTRACT FROM AUTHOR]

Carbon quantum dots (CQDs) were derived from saponin and introduced into polyacrylamide hydrogel to prepare a novel bifunctional material (CQDs@HG). This hydrogel emitted strong blue fluorescence under ultraviolet light (365 nm) and exhibited stable adsorption and detection of iron(III) in water samples. The morphological characteristics, chemical composition, Fe3+ adsorption performance, and optical properties of CQDs@HG were characterized. Depending upon the Fe3+ concentration, CQDs@HG exhibited different quenching effects to allow Fe3+ determination. The limit of detection was 0.115 μM, and the adsorption was as high as 12.13 mg/g. The mechanism was due to both static and dynamic quenching. Notably, the sensor based on CQDs@HG successfully determined Fe3+ in water samples, with spiked recoveries between 95.32% and 103.11%. When combined with software image analysis, the sensor semi-quantitatively determined Fe3+ in the field. This fluorescent hydrogel provides a reference for constructing portable sensors for monitoring hazardous substances in water. [ABSTRACT FROM AUTHOR]

In this article, we present a method for generating (2 + 1)-dimensional integrable equations, resulting in the generalized Pavlov equation and dispersionless Kadomtsev–Petviashvili (dKP) equation, which can further be reduced to the standard Pavlov equation and dKP equation. Inspired by the inverse spectral transform presented in existing literature, we introduce the Riemann–Hilbert (RH) dressing method to construct the formal solutions of the Cauchy problems for the generalized Pavlov equation and dKP equation, providing a spectral representation of the solutions. Subsequently, we also extensively investigate the longtime behavior of solutions to these two equations in specific space regions. In particular, for the generalized dKP equation, we conduct a dedicated study on its implicit solutions expressed by arbitrary differential function through linearizing their RH problems. In the final section, we elaborate in detail on the analytic aspects of the wave breaking of a localized two-dimensional wave evolving according to the Hopf equation. With the assistance of a transformation, the longtime breaking of solutions to the generalized dKP equation can then be further characterized. [ABSTRACT FROM AUTHOR]