Online learning during the COVID-19 pandemic: the wellbeing of Chinese migrant children-a case study in Shanghai.

Introduction: This study uses Bronfenbrenner's bioecological model as its theoretical framework to consider the findings of an investigation of the emotional, social, and physical wellbeing of Chinese migrant children and lessons learned from the COVID-19 pandemic in urban areas. This study expands our perspective by combining the views of students, parents, and teachers to explore the emotional, social and physical wellbeing of migrant children in Shanghai who were participating in online learning during the COVID-19. Methods: Observation and semi-structured interviews were carried out to collect data for this case study. Thirty-one migrant children, nine parents, 10 teachers and a school principal from a Shanghai junior high school participated in this research. Qualitative data were analyzed using thematic analysis. Results and Discussion: The findings indicated that although video-recorded lessons were high quality, it put pressure on migrant children due to the lessons containing only new material with no reviews and reduced opportunities for them to interact with their own teachers. In addition, the differences in study progress between the migrant children and the local children that showed up during the online learning, and neglect from teachers and policymakers, made the migrant children anxious, angry and confused about their future. Besides, parents install monitors at home to support their children's online learning, but it had the opposite effect and simply provoked increased conflicts between children and their parents. Finally, although the online lessons have affected the optical health of students, the subsequent additional cooking lessons have mitigated the optical health problem and strengthened the connections between home and school. Conclusion: The inequalities of education encountered by migrant children during the COVID-19 period have made them realize the disparities they have suffered in Shanghai. The exposure of this problem raises the prospect of a reform of educational policies for migrant children in the future.

Novel Chalcone-Phenazine Hybrids Induced Ferroptosis in U87-MG Cells through Activating Ferritinophagy.

Thirty-seven novel chalcone-phenazine hybrid molecules (C1∼C13 and F1∼F24) with 1,2,3-triazole or ethyl group as linkers were designed and synthesized in this study. Some compounds exhibited selective cytotoxicity against U87-MG cancer cell lines in vitro, in which compound C4 were found to have the best antiproliferative activity. SAR study indicated 1,2,3-triazole group may be crucial for enhancing compounds' cytotoxicity. C4 was verified to induce ferroptosis in U87-MG cells by transcription, lipid peroxidation, lipid ROS assays. Furthermore, C4 was up-regulated LC3-II, degradated FTH1, and then increasing iron resulted in the down-regulation of NCOA4. Together, all above evidences highlighted the potential of compound C4 that triggered ferroptosis by activating ferritinophagy against U87-MG cells.

A thioredoxin reductase 1 inhibitor pyrano [3,2-a] phenazine inhibits A549 cells proliferation and migration through the induction of reactive oxygen species production.

BACKGROUND: Thioredoxin reductase 1 (TrxR1) inhibitor, pyrano [3,2-a] phenazine, named CPUL-1, was synthesized with potential anticancer activity. The aim of the present work was to explore the potential anti-proliferative and anti-metastatic ability of CPUL-1 against A549 cancer cell lines in vitro. METHODS AND RESULTS: First, Cell Counting Kit-8 (CCK8) assay was used to assess cell proliferation. The A549 cell migration was evaluated by wound healing assay and transwell assay. Second, the epithelial-mesenchymal transition (EMT)-related proteins in A549 cells treated with CPUL-1 were analyzed by western blot methods. Then, TrxR1 enzyme activity assay and reactive oxygen species (ROS) assay were conducted to evaluate the effect of CPUL-1 on TrxR1 inhibition and ROS levels. Finally, western blotting was used to explore the mechanism of CPUL-1. The study results revealed that the ability of cell proliferation and migration was decreased under CPUL-1 treatment. CPUL-1 could distinctly restrain the migration and invasion of A549 cells through inhibiting EMT process. The results of TrxR1 enzyme activity assay, ROS assay and western blotting showed that CPUL-1 influenced EMT via inducing ROS-mediated ERK/JNK signaling by inhibiting TrxR1 enzyme activity. CONCLUSIONS: Together, proliferation suppression and anti-metastasis activity of CPUL-1 in A549 cells were demonstrated by all the evidence. Our findings highlight the great potential of phenazine compound CPUL-1 to suppress A549 cells proliferation and metastasis.

Interactive Prosodic Marking of Focus, Boundary and Newness in Mandarin.

The current study investigates whether and how focus, phrase boundary and newness can be simultaneously marked in speech prosody in Mandarin Chinese. Homophones were used to construct three syntactic structures that differed only in boundary condition, focus was elicited by preceding questions, while newness of postboundary words was manipulated as whether they had occurred in the previous text. Systematic analysis of F0 and duration showed that (1) duration was a reliable correlate of boundary strength regardless of focus location, while involvement of F0 was only in terms of lowering of phrase-final F0 minima and raising of phrase-initial F0 minima at a relatively strong boundary, (2) postfocus compression (PFC) of F0 was applied across all boundaries, including those with long silent pauses (over 200 ms), and postfocus F0 was lowered to almost the same degree in all boundary conditions, and (3) newness of postfocus words had no systematic effect on F0 or duration. These results indicate that not only functionally focus is independent of prosodic structure and newness, but also phonetically its realization is separate from boundary marking. Focus is signaled mainly through pitch range adjustments, which can occur even across phrase breaks, whereas boundaries are mostly signaled by duration adjustments.