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The outstanding properties of perovskites have attracted huge attention in optoelectronic applications. However, the current study mainly focuses on small-area single-layer perovskite films. Surface modification of the polydimethylsiloxane (PDMS) surface has the potential for successful transfer of perovskite thin films and also for forming perovskite/perovskite heterostructures. Nevertheless, current PDMS surface modification processes suffer from fast hydrophobicity gain, thus greatly inhibiting their use in printing perovskite films. In this study, grafting-assisted modification of PDMS was done and long-term hydrophilic PDMS stamps were achieved, making them effective for use in printing perovskite thin films. Highly crystalline MAPbI3 and MAPbBrI2 perovskite films were successfully printed with good surface coverage, and the corresponding solar cell devices exhibited outstanding power conversion efficiencies of approximately 14 and 7%, respectively. This grafting-assisted PDMS printing technique also overcame the problem of dissolution in forming stacked perovskite/perovskite heterostructures by solution processibility. As a proof of concept, a cascaded MAPbBrI2/MAPbI3 heterostructure was prepared by transferring an MAPbI3 layer on top of an MAPbBrI2 layer. Thus, grafting-assisted PDMS emerged as a promising technique for fabricating stacked perovskite films, opening up avenues for fabricating large-area solution-processable perovskite/perovskite heterostructures for various fields of optoelectronics.

The present study was an elaboration on factors influencing for- eign language (FL) reading anxiety in EFL learners (n = 202) in Taiwan. Data were collected from three measures, a background information questionnaire, the Foreign Language Reading Anxiety Scale (FLRAS) and a semi-structured interview. The results showed that FL reading anxiety was associated with time spent on reading English, but not with gender and academic major. Moreover, FL reading anxiety was found to be positively correlated with text features and personal factors, but negatively correlated with reading strategy use, indicating that the more reading strategies a learner employs, the lower FL reading anxiety level he/she will experience. Unfamiliar vocabulary, unknown topics, long and complicated text structure as well as the fear of making mistakes were identified as the major factors of FL reading anxiety. This study contributes to extending our understanding of factors that might evoke EFL reading anxiety.

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Background: Traumatic brain injury (TBI) initiates a neuroinflammatory cascade that contributes to neuronal damage and behavioral impairment. This study was undertaken to investigate the effects of wogonin, a flavonoid with potent antiinflammatory properties, on functional and histological outcomes, brain edema, and toll-like receptor 4 (TLR4)-and nuclear factor kappa B (NF-kB)-related signaling pathways in mice following TBI.Methodology/Principal Findings: Mice subjected to controlled cortical impact injury were injected with wogonin (20, 40, or 50 mg?kg 21 ) or vehicle 10 min after injury. Behavioral studies, histology analysis, and measurement of blood-brain barrier (BBB) permeability and brain water content were carried out to assess the effects of wogonin. Levels of TLR4/NF-kB-related inflammatory mediators were also examined. Treatment with 40 mg?kg 21 wogonin significantly improved functional recovery and reduced contusion volumes up to post-injury day 28. Wogonin also significantly reduced neuronal death, BBB permeability, and brain edema beginning at day 1. These changes were associated with a marked reduction in leukocyte infiltration, microglial activation, TLR4 expression, NF-kB translocation to nucleus and its DNA binding activity, matrix metalloproteinase-9 activity, and expression of inflammatory mediators, including interleukin-1b, interleukin-6, macrophage inflammatory protein-2, and cyclooxygenase-2.Conclusions/Significance: Our results show that post-injury wogonin treatment improved long-term functional and histological outcomes, reduced brain edema, and attenuated the TLR4/NF-kB-mediated inflammatory response in mouse TBI. The neuroprotective effects of wogonin may be related to modulation of the TLR4/NF-kB signaling pathway.