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This study aimed to verify the applicability of the community of inquiry (CoI) survey instrument in MOOC involving 1,186 college students from 11 different disciplines in China. Exploratory factor analysis was used to explore potential factor structure models, and confirmatory factor analysis was utilized to verify the four-factor structure obtained from exploratory factor analysis. The original three- and new six-factor structure models were also included in the study. Confirmatory factor analysis results indicating that all three models fit very well with the data. Then Chi-square difference test was used to select the optimal model. Results indicate that the six-factor structure model with teaching presence, social presence, cognitive presence, design and organization, affective expression, and resolution is the optimal one, with good convergent and discriminant validity. Especially, the chi-square difference results indicate that design and organization can be significantly distinguished from teaching presence, whereas affective expression can be significantly distinguished from social presence, and resolution can be significantly distinguished from cognitive presence. Based on these findings, the present study argues that the six-factor structure model can provide a better understanding for the fine design and implementation of MOOC.

From 2 August to 4 August in 2023, a prolonged and extensive extreme heavy rainfall event occurrs in the southeast of Heilongjiang Province. Utilizing multiple observations and ERA5 reanalysis data, characteristics of the precipitation process are analyzed focusing on large-scale circulation background, mesoscale circulation system evolution, environmental conditions from perspectives of climate statistics, weather analysis, and physical quantity diagnosis. Factors contributing to the prolonged extreme heavy rainfall event are explored. Main causes for the long duration of this heavy precipitation event are the stable maintenance of favorable large-scale conditions, such as the persistent divergence of the upper troposphere, the stable location of the west Pacific subtropical high (WPSH) and Northeast China cold vortex (NCCV), and continuous water vapor transport by the southwest jet. Due to the strong southwest jet, there is abundant moisture transfer, primarily through the advection of water vapor, which is the primary source for heavy rainfall. The process can be divided into two stages due to significant differences of rainfall, atmospheric stratification, and local circulation characteristics. In the first stage, the meridional water vapor inflow layer and the saturated layer are thick, resulting in high tropospheric humidity. The atmospheric condition is characterized by weak convective instability. Under the control of the northwest airflow at 500 hPa, the development of southwest jet, along with the influence of a weak eastward-moving vortex system at 850 hPa, results in horizontal wind speed convergence and systematic upward motion, leading to widespread and prolonged precipitation. The heavy rainfall area is mainly composed of cumulus embedded stratus, with a large coverage area of the cloud system, low echo centroid height, and high precipitation efficiency. With weak convective instability that promotes the development of convection and train effect in some periods, extreme hourly precipitation and large cumulative precipitation occur. In the second stage, the meridional water vapor inflow is concentrated in the lower troposphere with high intensity. The lower troposphere is close to saturation, with high humidity and temperature, while the middle and upper troposphere is dry and cold, and the atmospheric condition is more unstable than that in the first stage. Convection is developed and strengthened by the combined action of systematic uplift by a trough at 500 hPa, warm shear at 850 hPa, topographic convergence, and uplift. The cloud system is dominated by local strong cumulus clouds, and the distribution of precipitation intensity is uneven. At the beginning of this stage, convective cells continue to form at the trumpet-shaped terrain and move towards the eastern mountainous areas, organizing into linear convection. This is accompanied by the development and southward movement of surface convergence lines, leading to the generation of new convection and continuously causing localized intense short-duration rainfall.

Mitigation solutions are often evaluated in terms of costs and greenhouse gas reduction potentials, missing out on the consideration of direct effects on human well-being. Here, we systematically assess the mitigation potential of demand-side options categorized into avoid, shift and improve, and their human well-being links. We show that these options, bridging socio-behavioural, infrastructural and technological domains, can reduce counterfactual sectoral emissions by 40–80% in end-use sectors. Based on expert judgement and an extensive literature database, we evaluate 306 combinations of well-being outcomes and demand-side options, finding largely beneficial effects in improvement in well-being (79% positive, 18% neutral and 3% negative), even though we find low confidence on the social dimensions of well-being. Implementing such nuanced solutions is based axiomatically on an understanding of malleable rather than fixed preferences, and procedurally on changing infrastructures and choice architectures. Results demonstrate the high mitigation potential of demand-side mitigation options that are synergistic with well-being.

Background: Self-regulated learning (SRL) ability is the key determinant of the success of full-time online learning. Thus, exploring the influencing factors of SRL and their influencing mechanisms is necessary to improve this ability among K-12 students. Objectives: The purpose of this study was to investigate the influence mechanism of teacher autonomy support on students' online SRL by examining the structural relationship among teacher autonomy support, parental autonomy support, students' self-efficacy, and students' online SRL. Methods: We use structural equation modelling and effect analysis to analyse the collected data from 961 Chinese K-12 students who engaged in full-time online learning in their homes during the coronavirus disease 2019 (COVID-19) outbreak. Results and Conclusions: Parental autonomy support and students' self-efficacy play crucial independent mediating roles in the influence of teacher autonomy support on students' online SRL. Parental autonomy support and students' self-efficacy have a chain mediating effect on the influence of teacher autonomy support on students' online SRL. Implications: On the basis of the results, we suggest that in order to develop students' online SRL ability, it is important for teacher to improve parental autonomy support and students' self-efficacy. In addition, base on the chain mediating effect, to improve students' online SRL, teacher autonomy support needs focus on parental autonomy support, and then parental autonomy support needs focus on improving students' self-efficacy.

Prefabricated buildings are increasingly advocated for their benefits, which include a shortened construction period, cost-efficiency, and enhanced resource utilization. However, the comparison between prefabricated and cast-in-place buildings on life-cycle carbon emissions is still insufficient. This study assesses and analyses the life cycle carbon emission of both types of structures and achieves carbon reduction strategies at various life cycle stages from actual cases. The analysis reveals that for both modular and cast-in-place buildings, the materials contributing the most to carbon emissions are concrete blocks, concrete, steel rebar, formwork, and wall plaster. In addition, the formwork in prefabricated buildings constitutes nearly half of the total carbon emissions during the construction stage compared to cast-in-place structures. In the maintenance phase, cast-in-place buildings are more low-carbon than prefabricated buildings because the insulation can be replaced. During the dismantling stage, carbon emissions from prefabricated buildings are approximately 11.31% lower than those from cast-in-place structures. The study also introduces several carbon reduction measures, for example, substantial emission reductions can be attained by substituting ordinary Portland cement with new dry process cement, employing RRAC concrete over regular concrete, utilizing lightweight aggregate concrete blocks instead of aerated concrete blocks, and opting for recycled steel. Regarding the operational phase, the implementation of solar photovoltaic panels on building rooftops has been proven to effectively curtail carbon emissions.

The literature on planetary and Earth system boundaries calls on humans to live within those boundaries. Sharing such limited ecospace raises questions of justice. Global environmental assessments and scholarship are increasingly paying attention to justice issues, yet inadequately define how to share the limited ecospace. Against this background we ask: how can global environmental assessments' concerns for justice be enhanced through an Earth system justice framework that guides how the global community could share limited ecospace? Based on an analysis of how justice concerns are addressed in the Assessment of Assessments and global environmental change projects, we build an Earth system justice framework that discusses how ecospace can be shared fairly through the setting of Earth system boundaries and the provision of minimum resource needs for all, and how this can be achieved through an equitable redistribution of resources, rights, and responsibilities focused on addressing inequality, overconsumption, and harmful accumulation. [ABSTRACT FROM AUTHOR]