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Computational thinking (CT) is regarded as the conceptual basis required for identifying and solving real-world problems through algorithmic approaches to achieve transferable solutions. Developing students' CT in primary school stages is essential and has received considerable attention. Meanwhile, researchers incorporated digital badges into classrooms to improve students' learning motivation in computer science (CS). However, few solid empirical studies analyze the effects of the digital badges approach in CS education to develop students' CT. Therefore, to bridge this gap, this study designed and implemented a block-based programming course in a primary school and examined the impact of the digital badges approach on pupils' CT skills and self-efficacy and learning motivation in CS. A quasi-experimental design was conducted among 99 third-grade students across three classes. The results revealed that the adapted digital badges in primary school (1) significantly improved the students' CT skills, (2) had no significant positive impact on their CT self-efficacy or learning motivation in CS, and (3) showed no mediating effect of learning motivation on the relationship between CT skills and CT self-efficacy. In addition, we found that whether students could see only their own digital badges or also those of others had no impact on CT skills, self-efficacy, or learning motivation in CS. These findings have implications for the design of digital badge educational interventions intended to promote students' CT and learning motivation.

Despite the significant advancements in cancer treatment brought by immune checkpoint inhibitors (ICIs), their effectiveness in treating glioblastoma (GBM) remains highly dissatisfactory. Immunotherapy relies on the fundamental concept of T cell-mediated tumor killing (TTK). Nevertheless, additional investigation is required to explore its potential in prognostic prediction and regulation of tumor microenvironment (TME) in GBM. TTK sensitivity related genes (referred to as GSTTKs) were obtained from the TISIDB. The training cohort was available from the TCGA-GBM, while the independent validation group was gathered from GEO database. Firstly, we examined differentially expressed GSTTKs (DEGs) with limma package. Afterwards, the prognostic DEGs were identified and the TTK signature was established with univariate and LASSO Cox analyses. Next, we examined the correlation between the TTK signature and outcome of GBM as well as immune phenotypes of TME. Furthermore, the evaluation of TTK signature in predicting the effectiveness of immunotherapy has also been conducted. We successfully developed a TTK signature with an independent predictive value. Patients who had a high score experienced a worse prognosis compared to patients with low scores. The TTK signature showed a strong positive association with the infiltration degree of immunocyte and the presence of various immune checkpoints. Moreover, individuals with a lower score exhibited increased responsiveness to ICIs and experienced improved prognosis. In conclusions, we successfully developed and verified a TTK signature that has the ability to predict the outcome and immune characteristics of GBM. Furthermore, the TTK signature has the potential to direct the personalized immunotherapy for GBM.

The crosslinking network structure is a crucial factor influencing the properties of natural rubber. Therefore, investigating the impact of different vulcanization bond types on the strain-induced crystallization behavior and properties of natural rubber can provide a theoretical foundation for producing high-performance natural rubber. In this study, diverse curing systems were employed to produce vulcanized natural rubbers with varying crosslink types. The crosslinking network structures of the vulcanized rubbers were analyzed using the tube model theory. Additionally, the effects of vulcanization bonds on strain-induced crystallization behavior and tensile properties were examined through in-situ X-ray diffraction and a tensile testing machine. The results revealed that the vulcanizate with monosulfidic bonds, formed under the effective vulcanization (EV) system, primarily comprised chemical crosslinking networks, resulting in a high tensile modulus, low elongation at break, and low tensile strength. Conversely, the vulcanizate under the conventional vulcanization (CV) system exhibited a distinct entanglement network impact compared to the chemical crosslinking network, resulting in a smaller tensile modulus but the highest elongation at break and the largest tensile strength. These differences stemmed from the distinct roles of vulcanization bonds within the crosslinking network. Specifically, the relatively short monosulfidic bond quickly reached the critical degree of orientation for crystallization during stretching, leading to higher crystallinity under the same strain. However, its shorter length caused earlier fracture during stretching, resulting in network heterogeneity, reduced elongation at break, and lower tensile strength. On the other hand, the longer polysulfidic bond underwent fracture recombination during stretching, with slower orientation and delayed crystallization. Nonetheless, this recombination improved network uniformity and integrity due to stress dissipation from the initial fracture, enhancing crystallinity, elongation at break, and tensile strength. This study elucidated the influence of vulcanization crosslinking on the tensile properties of vulcanizates.

The realization of mid-infrared thermal radiation based on metamaterials insensitive to angle and polarization plays an important role in various thermal photonic applications. However, the challenges include the following: most previously designed thermal emitters usually contain metal components with unsatisfied physicochemical stability, accompanied with complex manufacturing technology. The present study proposes a mid-infrared thermal emitter at 3–6 μm wavelength range based on Fibonacci quasi-periodic structure, and a flat one-dimensional structure based on Fibonacci geometry resorting to ITO is designed. The proposed thermal emitter is, theoretically and experimentally, proven to possess good angular and polarization-independent selective thermal emission performance in a relatively wide infrared wavelength range. Furthermore, the good optical and high-temperature thermal stability of the designed thermal emitter is verified in the present experimental research. The thermal emitters proposed have advantages in polarization-independence without scale restraint and low cost but with wide vision. In summary, the present study provides a new tactics for obtaining non-metal spectral selective thermal emitters in a relatively wide wavelength range and thermal photonic applications under harsh conditions.

Objectives: The role of asymptomatic infections in the transmission of COVID-19 have drawn considerable attention. Here, we performed a meta-analysis to summarize the epidemiological and radiographical characteristics of asymptomatic infections associated with COVID-19. Methods: Data on the epidemiological and radiographical characteristics of asymptomatic infections were extracted from the existing literature. Pooled proportions with 95% confidence intervals were then calculated using a random effects model. Results: A total of 104 studies involving 20,152 cases were included. The proportion of asymptomatic individuals among those with COVID-19 was 13.34% (10.86%–16.29%), among which presymptomatic and covert infections accounted for 7.64% (4.02%–14.04%) and 8.44% (5.12%–13.62%), respectively. The proportions of asymptomatic infections among infected children and healthcare workers were 32.24% (23.08%–42.13%) and 36.96% (18.51%–60.21%), respectively. The proportion of asymptomatic infections was significantly higher after 2020/02/29 than before (33.53% vs 10.19%) and in non-Asian regions than in Asia (28.76% vs 11.54%). The median viral shedding duration of asymptomatic infections was 14.14 days (11.25–17.04). A total of 47.62% (31.13%–72.87%) of asymptomatic infections showed lung abnormalities, especially ground-glass opacity (41.11% 19.7%–85.79%). Conclusions: Asymptomatic infections were more commonly found in infected children and healthcare workers and increased after 2020/02/29 and in non-Asian regions. Chest radiographical imaging could be conducive to the early identification of asymptomatic infections.

The effect of crystal size of HMOR from micro size to 50 nm, with the apparent similar acid site density, on catalytic performance for the dimethyl ether (DME) carbonylation was investigated. The crystal size of HMOR is sensitive to the deactivation rate of DME carbonylation reaction, and the higher stability around 200 nm can be achieved. The characterization studies reveal that the diffusions of MA product play a key role during the induction and deactivation period in DME carbonylation. These will be helpful for guiding the large-scale synthesis of mordenite zeolites catalysts with high efficiencies for DME carbonylation.