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Abstract Previous studies have shown that scutellarin inhibits the excessive activation of microglia, reduces neuronal apoptosis, and exerts neuroprotective effects. However, whether scutellarin regulates activated microglia-mediated neuronal apoptosis and its mechanisms remains unclear. This study aimed to investigate whether scutellarin can attenuate PC12 cell apoptosis induced by activated microglia via the JAK2/STAT3 signalling pathway. Microglia were cultured in oxygen–glucose deprivation (OGD) medium, which acted as a conditioning medium (CM) to activate PC12 cells, to investigate the expression of apoptosis and JAK2/STAT3 signalling-related proteins. We observed that PC12 cells apoptosis in CM was significantly increased, the expression and fluorescence intensity of the pro-apoptotic protein Bax and apoptosis-related protein cleaved caspase-3 were increased, and expression of the anti-apoptotic protein B-cell lymphoma-2 (Bcl-2) was decreased. Phosphorylation levels and fluorescence intensity of the JAK2/STAT3 signalling pathway-related proteins JAK2 and STAT3 decreased. After treatment with scutellarin, PC12 cells apoptosis as well as cleaved caspase-3 and Bax protein expression and fluorescence intensity decreased. The expression and fluorescence intensity of Bcl-2, phosphorylated JAK2, and STAT3 increased. AG490, a specific inhibitor of the JAK2/STAT3 signalling pathway, was used. Our findings suggest that AG490 attenuates the effects of scutellarin. Our study revealed that scutellarin inhibited OGD-activated microglia-mediated PC12 cells apoptosis which was regulated via the JAK2/STAT3 signalling pathway.

The Lawson's Classroom Test of Scientific Reasoning (LCTSR) is a popular instrument that measures the development of students' scientific reasoning skills. The instrument has a two-tier question design, which has led to multiple ways of scoring and interpretation. In this research, a method of pattern analysis was proposed and applied to analyze two-tier item pairs on the subskill of Control-of-Variable (COV) of LCTSR. The data were collected from students in grade 4 through college in both the United States and China. Students' response patterns to two combined item pairs were analyzed and compared against students at different grade levels and reasoning development levels. Six performance levels were established based on students' response patterns, serving as indicators of COV reasoning development levels. With the new method, a relation was obtained between students' level of COV skills and grade level, as well as their level of overall reasoning development. It can provide useful information on the possible developmental levels of students' reasoning skills.

Most studies have concentrated in assessing students' overall attitudes towards science, mathematics, and engineering/technology or the attitude towards individual STEM domain. The present research aims to explore primary students' gender and grade differences of their STEM domain-specific attitudes including self-efficacy and expectancy-value beliefs, as well as their correlations. The results showed no detected significant effects among these different STEM domains in the overall attitudes, the overall self-efficacy beliefs, and the overall expectancy-value beliefs for primary students. The correlations between self-efficacy and expectancy-value were much stronger for the science domain and engineering/technology domain than the mathematics domain. No gender difference of the self-efficacy beliefs was detected except in the mathematics domain, and the result that lower primary students performed significantly better than upper primary students in the self-efficacy was also mainly contributed by the grade difference in the mathematics domain. Whereas no different expectancy-value beliefs existed across genders and grade levels in various STEM domains. The present results reported some unique performances by the primary school students compared to the elder group.

In recent years, game-based learning has attracted much attention in education; however, the effectiveness of game-based learning is still not solidly confirmed. In the present research, a game-based learning in the physics domain with guides provided direct and immediate feedback. The research was conducted among three different groups: the traditional group, the educational video group, and the game-based learning group. The result showed that the game-based learning group performed the best among the three groups, followed by the educational video group, and the traditional group performed the worst. Students in the game-based learning group were enrolled into an interview to study which types of guides enhanced students' game-based learning. From the interview, the prompts and the interactive characteristic of the game-based learning environment took the first two places. In addition, students benefited from the features of game-based learning including task requirements for execution, the tip prompt function, the feedback mechanism, and the story settings. Therefore, it is necessary to integrate applicable guides into the design of game-based learning according to students' perspectives for providing engaging learning experience.

Abstract Scutellarin is used to treat brain ischaemia. However, its underlying mechanism of action remains unclear. This study aimed to elucidate the potential mechanism of action of scutellarin in brain ischaemia through network pharmacology and experimental verification. The JAK2/STAT3 signalling pathway was identified and experimentally verified. Expression of JAK2/STAT3 signalling related proteins in TNC-1 astrocytes with BV-2 microglia-conditioned medium (CM), CM + lipopolysaccharide (LPS) (CM + L), and CM pretreated with scutellarin + LPS (CM + SL) was analysed by Western Blot and immunofluorescence staining. Expression levels of JAK2, p-JAK2, STAT3, and p-STAT3 were evaluated in astrocytes pre-treated with AG490. Middle cerebral artery occlusion (MCAO) in rats was performed in different experimental groups to detect expression of the above biomarkers. Network pharmacology suggested that the JAK2/STAT3 signalling pathway is one of the mechanisms by which scutellarin mitigates cerebral ischaemic damage. In TNC-1 astrocytes, p-JAK2 and p-STAT3 expression were significantly up-regulated in the CM + L group. Scutellarin promoted the up-regulation of various markers and AG490 neutralised the effect of scutellarin. In vivo, up-regulation of p-JAK2 and p-STAT3 after ischaemia is known. These results are consistent with previous reports. Scutellarin further enhanced this upregulation at 1, 3, and 7 d after MCAO. Scutellarin exerts its therapeutic effects on cerebral ischaemia by activating the astrocyte JAK2/STAT3 signalling, which provides a firm experimental basis for its clinical application.

Bisphenol A (BPA) is a widespread environmental pollutant linked to detrimental effects on human health and reduced life expectancy following chronic exposure. This prospective cohort study aimed to examine the association between BPA exposure and mortality in American adults and to explore the potential mitigating effects of dietary quality on BPA-related mortality. This study utilized data from 8761 American adults in the 2003–2016 National Health and Nutrition Examination Survey (NHANES). Urinary BPA levels were employed to assess BPA exposure, and dietary quality was evaluated using the Healthy Eating Index-2015 (HEI-2015). All-cause, cardiovascular disease (CVD), and cancer mortality statuses were determined until December 31, 2019, resulting in a cumulative follow-up of 80,564 person-years. The results showed that the highest tertile of urinary BPA levels corresponded to a 36% increase in all-cause mortality and a 62% increase in CVD mortality compared to the lowest tertile. In contrast, the highest tertile of HEI-2015 scores was associated with a 29% reduction in all-cause mortality relative to the lowest tertile. Although no significant interaction was found between HEI-2015 scores and urinary BPA levels concerning mortality, the association between HEI-2015 scores and both all-cause and CVD mortality was statistically significant at low urinary BPA levels. Continuous monitoring of BPA exposure is crucial for evaluating its long-term adverse health effects. Improving dietary quality can lower all-cause mortality and decrease the risk of all-cause and CVD mortality at low BPA exposure levels. However, due to the limited protective effect of dietary quality against BPA exposure, minimizing BPA exposure remains a vital goal.

为提升燃料的综合燃烧品质和性能，进一步降低有害物质排放和缓解温室效应，以燃烧动力学和化学反应机制作为理论基础，采用Chemkin软件将生物柴油替代物和氨气充分融合，模拟并计算氨气掺混比例分别为0、5%、10%、15%、20%的5组燃料在均质压燃发动机模式下燃烧和排放指标的数值，对比分析得到不同掺混比例对发动机燃烧和排放的影响和变化规律。结果表明：随着氨气掺混比例增加，燃料的点火滞燃期有所缩短，缸内燃烧最高温度升高，排温降低；排放方面，NOx的排放升高，CO2、CO和总碳氢化合物（THC）的排放均明显降低；生物柴油掺混氨气的最佳比例为20%，此时发动机功率下降12百分点，NO的单位功率排放升高了0.003 kW-1，而CO2和THC的单位功率排放分别降低了0.01 kW-1和0.001 3 kW-1。综上，生物柴油掺混氨气后改善了燃烧性能，降低了排放量，具有良好的应用前景 In order to improve the comprehensive combustion quality and performance of the fuel, further reduce the emission of harmful substances and mitigate the greenhouse effect, based on the theoretical basis of combustion kinetics and chemical reaction mechanism, the Chemkin software was used to fully integrate the mechanism of biodiesel substitute and ammonia gas, simulate and calculate the combustion and emission values of 5 groups of fuels with the ammonia gas molar ratio of 0, 5%, 10%, 15% and 20% respectively in homogeneous charge compression ignition engine mode. The effects and change rule of different mixing ratio on engine combustion and emission were compared and analysed. The results showed that with the increase of ammonia gas ratio, the ignition delay period of fuel was shortened, the maximum combustion temperature in the cylinder increased, and the exhaust temperature decreased. In terms of emission, NOx emission increased, while CO2, CO and total hydrocarbon (THC) emissions decreased significantly. The optimal ratio of biodiesel blended with ammonia gas was 20%, and under this condition, the engine power decreased by 12 percentage, and the unit power emission ratio of NO increased by 0.003 kW-1, while the unit power emission ratios of CO2 and THC decreased significantly, which were 0.01 kW-1 and 0.001 3 kW-1 respectively. In conclusion, biodiesel blended with ammonia gas significantly improves combustion and reduces emissions, and has good application prospect.