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Autonomy of language learners in technology-supported learning environments has attracted much scholarly attention. However, few studies, to date, have examined the issue in the emerging context of language MOOCs. The present study complemented this line of research via a qualitative investigation of a group of Chinese EFL learners in an English language MOOC. Data were collected via a prior interview (N = 38), four interviews held at different stages of the MOOC (N = 36, 27, 17, 13, respectively), and a post-course interview for dropouts (N = 14). A framework consisting of seven constructs in three dimensions, namely, the situational, the behavioral, and the psychological, was employed for analyzing the data. The results showed that the learners exhibited individual and dimensional variation in the extent to which they exercised autonomy. Participants were also observed to have adopted a variety of metacognitive strategies, motivation control strategies, and emotion control strategies to regulate their learning. The findings highlight the complexity of learner autonomy as displayed in the new learning interface as well as the potential of language MOOCs for fostering learner autonomy.

For a long time, Australian English and culture have not been viewed in China as an equal to its American and British counterpart. This is reflected in teachers' choice of destination when it comes to English teaching and learning resources. This paper examines Chinese English as a foreign language (EFL) teachers' perceptions of the contents and pedagogical design of Australian-based digital English learning resources through an interactive process. The teachers' beliefs regarding language teaching and learning as well as materials selection were challenged due to the application of current technologies in the language education. A total of 24 EFL teachers from different universities across China participated in focus group interviews. The teachers worked with website designers and content writers to refine the design of the English language learning (ELL) website and digital English resources. Data showed that respondent teachers were highly receptive towards the newly designed ELL website as well as its content that were developed by incorporating the key features of a popular ELL website proposed by previous studies (Kettle, Yuan, Luke, Ewing & Shen, 2012; Shen, Yuan & Ewing, 2015; Yuan & Shen, 2013, 2014). In the interactive process of this study, participating teachers learned to appreciate Australian-based digital English resources, particularly the Australian culture, language and pedagogy embedded. A reflective process was also triggered in which Chinese EFL teachers showed willingness to re-examine their instructional practices and utilize the digital resources by adopting a more learner-centered pedagogy for optimal learning outcomes.

The chemical composition of individual particles can be revealed by single-particle mass spectrometers (SPMSs). With higher accuracy in the ratio of mass to charge (m/z), more detailed chemical information could be obtained. In SPMSs, the conventional standard-based calibration methods (internal/external) are constrained by the inhomogeneity of ionization lasers and the finite focusing ability of the inlet system, etc.; therefore, the mass accuracy is restricted. In this study, we obtained the detailed and reliable chemical composition of single particles utilizing a standard-free mass calibration algorithm. In the algorithm, the characteristic distributions of hundreds of ions were concluded and collected in a database denoted as prototype. Each single-particle mass spectrum was initially calibrated by a function with specific coefficients. The range of coefficients was constrained by the magnitude of mass deviation to a finite vector space. To find the optimal coefficient vector, the conformity of each initially calibrated spectrum to the prototype dataset was assessed. The optimum calibrated spectrum was obtained with maximum conformity. For more than 98 % ambient particles, a 20-fold improvement in mass accuracy, from ∼ 10 000 ppm (integer) to ∼ 500 ppm (two decimal places), was achieved. The improved mass accuracy validated the determination of adjacent ions with a m/z difference ∼ 0.05 Th. Furthermore, atmospheric particulate trace elements that were poorly studied before are specified. The obtained detailed single-particle-level chemical information could help explain the source apportionment, reaction mechanism, and mixing state of atmospheric particles. [ABSTRACT FROM AUTHOR]

Non‐methane volatile organic compounds (NMVOCs) have a significant impact on air quality in urban areas. Detecting NMVOCs emission with its proxy HCHO on urban scales from space, however, has been limited by the lack of discernible enhancement. Here we show clear urban HCHO plumes from 16 cities over the globe by rotating TROPOspheric Monitoring Instrument HCHO pixels according to wind directions. We fit the downwind structure of the plumes with the exponentially modified Gaussian approach to quantify urban HCHO effective production rates between 7.0 and 88.5 mol s−1. Our results are in line with total NMVOC emissions from the EDGAR inventory (r = 0.76). Our work offers a new measure of total NMVOC emissions from urban areas and highlights the potential of satellite HCHO data to provide new information for monitoring urban air quality. Plain Language Summary: Non‐methane volatile organic compounds (NMVOCs) play an important role in urban air quality. Formaldehyde (HCHO) satellite observations have been shown to be able to reliably track and quantify NMVOC emissions at global and regional scales. Here, we use state‐of‐the‐art satellite sensors to quantify effective HCHO production rates in 16 global cities and further constrain total NMVOC emissions. Our results are broadly consistent with current emissions inventories, implying that satellites may be able to provide new information for urban air studies. Key Points: We show clear urban HCHO plumes from 16 cities over the globe by relating satellite pixels with wind fieldsWe obtain urban effective HCHO production rates by fitting the downwind structure of HCHO plumesSatellite‐based effective HCHO production rates provide potential measures of total non‐methane volatile organic compound emissions [ABSTRACT FROM AUTHOR]

Brown carbon (BrC) absorption impacts radiative forcing and climate change. Quantifying radiative forcing of BrC requires understanding its molecular composition and absorption characteristics. While organic molecules surrounding BrC may impact its absorption, their effects have not yet been investigated. This research determined matrix effect on BrC absorption by comparing individual BrC molecules and BrC within an organic matrix. Over 20,000 water‐soluble organic molecules constituted the water‐soluble BrC and associated organic matrix. The matrix enhanced aliphatic BrC absorption but suppressed aromatic BrC, especially with higher matrix O/C ratios indicating greater polarity and acidity. By directly measuring and modeling organic matrix effect on BrC, we can improve climate prediction precision and aerosol‐radiation interaction comprehension. Plain Language Summary: In the atmosphere, organic carbon that absorb light are called brown carbon. Brown carbon can impact climate change. It is critical to understand potential factors affecting brown carbon's absorption of light. Our study proposed another potential influencing light absorbing of brown carbon, effect from organic matrix formed by co‐existing organic molecules. The matrix effect on brown carbon absorption was simulated by the absorption properties of individual molecules and the absorption contributions from the same molecules embedded within organic matrix. We found over 20,000 molecules in all samples, separating them into major contributing brown carbon molecules and co‐existing organic molecules. We found CHO and CHON formed the majority of these molecules. The organic matrix showed the different behavior to effect light absorption to different portion for organic molecules, namely aliphatic and aromatic brown carbon molecules. The brown carbon absorption was suppressed during the nighttime, with the high O/C ratio co‐existing organics. Through the direct measurement and modeling of organic matrix effect on brown carbon, the finding could improve the precision of climate predictions and enhance our comprehension of aerosol‐radiation interactions. Key Points: Organic molecules co‐existing around brown carbon constituted the organic matrixThe organic matrix enhanced aliphatic but suppressed aromatic brown carbon absorptionHigher matrix O/C ratios indicating greater polarity and acidity especially suppressed aromatic brown carbon absorption [ABSTRACT FROM AUTHOR]

The chemical composition of individual particles can be revealed by single particle mass spectrometers (SPMS). With higher accuracy in the ratio of mass to charge (m/z), more detailed chemical information could be obtained. In the SPMS, the conventional standard-based calibration methods (internal/external) are constrained by the inhomogeneity of ionization lasers and the finite focusing ability of the inlet system, etc., therefore, the mass accuracy is restricted. In this study, we obtained the detailed and trustable chemical composition of single particles utilizing a standard-free mass calibration algorithm. In the algorithm, the characteristic distributions of hundreds of ions were concluded and collected in a database denoted as prototype. Each single-particle mass spectrum was tentatively calibrated by a mass calibration function with specific coefficients. The range of coefficients is constrained by the magnitude of mass deviation to a finite vector space. To find the optimal coefficient vector, the conformity of each tentatively calibrated spectrum to the prototype dataset was assessed. With maximum conformity, the optimal calibrated spectrum was obtained. For more than 98 % ambient particles, a twentyfold improvement in mass accuracy, from ~10,000 ppm (integer) to ~500 ppm (2 decimal places) was achieved. The improved mass accuracy validated the determination of adjacent ions with m/z difference ~0.05 Th. Furthermore, atmospheric trace ions that were poorly studied before are successfully specified. The obtained detailed single-particle-level chemical information could help understand the source apportionment, reaction mechanism, and mixing state of atmospheric particles. [ABSTRACT FROM AUTHOR]

Following a series of actions in China, the annual mean fine particle (PM2.5) concentrations have considerably reduced since 2013. However, in some cities, the PM2.5 concentrations exceed the national ambient air quality standard of 35 μg/m3. Herein, we evaluated the historical trends of PM2.5 from 2014 to 2022 in mainland China and found continuously declining trends. However, the annual decline rates decreased despite increasing investments on pollution control, showing considerably diminishing marginal effects of these investments. Accumulative reduction in PM2.5 concentrations is linearly dependent on the log‐transformed accumulative investment in air pollution control. The standard of 35 μg/m3 can be achieved by 2035 if the current efforts continue at the same pace. However, the standard of 35 μg/m3 can weaken the momentum of future actions in cities where the standard has already been implemented. We proposed and tested two tiers with four or six levels of specific regional standards based on the regression model predictions from the historical data and demonstrated that more rigorous standards for regions where the current standard is already attained could provide more momentum for strengthening abatement efforts. The results show that both tiers are feasible if the level of abatement endeavor is maintained even with marginal effects. We also demonstrate that additional 135,000 or 384,000 deaths can be avoided by applying the regional standards. Health benefits are monetized and compared with the control costs, suggesting that compared to Tier‐2, Tier‐1 is more cost‐effective and balanced across the mainland China. Plain Language Summary: Air quality in China has substantially improved since 2013 and the goal of meeting the national standard of 35 μg/m3 is expected to be achieved by 2035. However, with significant spatial variations, a single standard will be very likely to weaken the momentum of future actions in cities where the standard has already been attained. We proposed two tiers of regional standards by quantifying the declining trends of PM2.5 since 2013 for individual provinces. The feasibility and cost–benefit of the regional standards were evaluated, and the environmental and health benefits of implementing the local standards were demonstrated. Key Points: Different regional air quality standards for PM2.5 are feasible and more beneficial than a single national one in ChinaImplementing the regional PM2.5 standards well developed in this study in 2035 will avoid additional 135,000–384,000 deaths [ABSTRACT FROM AUTHOR]

This design-based study examines the creation and development of audio-visual Chinese language teaching and learning materials for Australian schools by incorporating users' feedback and content writers' input that emerged in the designing process. Data were collected from workshop feedback of two groups of Chinese-language teachers from primary and secondary schools in Australia and content writers' reflections of their understanding and transformation of their understanding of Chinese teaching and learning materials for Australian schools. It is found that a reciprocal process between the users and content writers can effectively facilitate the creation and development of user-oriented teaching and learning materials which are sensitive to the local curriculum needs. Based on teachers' comments and content writers' ideas, appropriate audio-visual Chinese language teaching and learning materials need to be tailor-made with a range of topics focusing on current China. A strong pedagogical scaffolding needs to be embedded into the materials and tasks, supporting students' language learning in the classroom. The creation of Chinese texts needs to employ simple yet authentic language structures on topics of relevance to students' life. Findings also indicate that audio-visual resources need to be accompanied with quality images and subtitles. All audio recordings should be spoken by Chinese native speakers, who are fluent in standard Mandarin. Additionally, it is suggested that an interactive learning platform could effectively enhance peer learning.

English language learning (ELL) websites and digital resources have been recognized as an important source of linguistic and cultural knowledge for English as a foreign language (EFL) learners to explore. The up-to-date information carried by authentic materials is invaluable for learners to develop an understanding of the target language/culture. However, there appears to be a gap between what the designer intends and what the user wants. This paper investigates Chinese university EFL teachers' perceptions of online English language websites and resources. The study focuses on a number of components of major language areas and skills in ELL websites, website materials, language users' preferences, and website usability. A total of 1519 English academics from 139 universities across China completed the online survey, and 164 of them voluntarily participated in focus group interviews anonymously. The empirical evidence of this study has highlighted that a pedagogically-oriented ELL website, targeting audiences with a variety of language proficiencies, was much liked by the Chinese EFL teachers. A preference was observed to see more current authentic language, examination-oriented English learning materials and tasks, and Eastern/non-Anglophone topics in the websites. In addition, it is found that website usability is another key factor that would impact ELL website popularity. A well-designed ELL website can effectively assist Chinese EFL learners to enhance their language competence and achieve optimal learning outcomes. This study provides a context-specific empirical base for innovative web-based EFL learning and teaching as well as website design and materials development in China. The proposed key features of a preferred ELL website may help better inform website designers, content writers and evaluators in their ELL website design/evaluation.