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Background Online information on mpox (monkeypox) is not well studied. We have analysed the video content, information quality, and audience engagement of mpox-related videos on TikTok.Methods Using a hashtag-based searching strategy, we identified 2462 mpox-related videos on TikTok from 1 January to 11 August 2022; 85 were included after exclusion criteria screening. Videos were evaluated for content on features and treatment of mpox. Video and information quality was assessed using the DISCERN instrument and the Journal of the American Medical Association (JAMA) criteria. We recorded video source, evaluation scores, and viewer engagement metrics. The Kruskal-Wallis test was used for statistical analysis and multiple linear regression for factor-association studies.Results Of the 85 videos, two assessed all content topics and highlighted 33% of all content items in clinical guidelines. The overall average score for the videos was 39.56 of 80 on the DISCERN instrument and 1.93 of 4 on the JAMA criteria. No video met all JAMA criteria. Subgroup analysis based on author identity suggested the variance in video scores by source (p

The development of stimuli‐responsive circularly polarized luminescence (CPL) materials is quite attractive but challenging. Here, a pair of atomically precise enantiomers R/S‐Ag20 nanoclusters has been synthesized using chiral acid ligands. And then, stimuli‐responsive CPL materials were developed by assembling the chiral silver nanoclusters with an achiral bridging ligand. The atomically precise silver cluster‐assembled materials produce CPL with a dissymmetry factor (|glum|) of 1 × 10−3, through the high‐efficiency chiral induction process. More interestingly, the single CPL band at room temperature could quickly transform into highly separated dual CPL emissions at low temperature. This study provides a new strategy for the rational functionalization of chiral silver clusters in preparing cluster‐based CPL emitters and enriches the types of stimuli‐responsive CPL materials. [ABSTRACT FROM AUTHOR]

X‐ray imaging technology has achieved important applications in many fields and has attracted extensive attentions. Dynamic X‐ray flexible imaging for the real‐time observation of the internal structure of complex materials is the most challenging type of X‐ray imaging technology, which requires high‐performance X‐ray scintillators with high X‐ray excited luminescence (XEL) efficiency as well as excellent processibility and stability. Here, a macrocyclic bridging ligand with aggregation‐induced emission (AIE) feature was introduced for constructing a copper iodide cluster‐based metal–organic framework (MOF) scintillator. This strategy endows the scintillator with high XEL efficiency and excellent chemical stability. Moreover, a regular rod‐like microcrystal was prepared through the addition of polyvinyl pyrrolidone during the in situ synthesis process, which further enhanced the XEL and processibility of the scintillator. The microcrystal was used for the preparation of a scintillator screen with excellent flexibility and stability, which can be used for high‐performance X‐ray imaging in extremely humid environments. Furthermore, dynamic X‐ray flexible imaging was realized for the first time. The internal structure of flexible objects was observed in real time with an ultrahigh resolution of 20 LP mm−1. [ABSTRACT FROM AUTHOR]

The origins of the chiroptical activities of inorganic nanostructures have perplexed scientists, and deracemization of high-nuclearity metal nanoclusters (NCs) remains challenging. Here, we report a single-crystal structure of Rac-Ag70 that contains enantiomeric pairs of 70-nuclearity silver clusters with 20 free valence electrons (Ag70), and each of these clusters is a doubly truncated tetrahedron with pseudo-T symmetry. A deracemization method using a chiral metal precursor not only stabilizes Ag70 in solution but also enables monitoring of the gradual enlargement of the electronic circular dichroism (CD) responses and anisotropy factor gabs. The chiral crystals of R/S-Ag70 in space group P21 containing a pseudo-T-symmetric enantiomeric NC show significant kernel-based and shell-based CD responses. The small symmetry breaking of Td symmetry arising from local distortion of Ag−S motifs and rotation of the apical Ag3 trigons results in large chiroptical responses. This work opens an avenue to construct chiral medium/large-sized NCs and nanoparticles, which are promising for asymmetric catalysis, nonlinear optics, chiral sensing, and biomedicine. Having control over the chirality of metal nanoclusters is challenging. Here, the authors report the deracemization of silver nanoclusters and monitor the chiroptical responses. [ABSTRACT FROM AUTHOR]

Superstructures made from nanoscale clusters with new collective properties are promising in high-tech applications; however, chiral superstructures remain elusive, and the limited intercluster coupling effect at room temperature hampers the tailoring of collective properties. Here, we show that from chiral monomeric copper clusters to two enantiomeric pairs of supercrystals with distinct phases, the absorption band edge red-shifts by over 1.3 eV, with photoluminescence and circularly polarized phosphorescence from visible (572 nm) to near-infrared (NIR, 858 nm). These supercrystals with high NIR quantum yields of up to 45% at room temperature are prototyped for night-vision imaging. In response to solvent and temperature stimuli, chiral supercrystal-to-supercrystal transformations occurred, concomitant with high-contrast optical/chiroptical switching. In situ single-crystal X-ray diffraction (SCXRD), steady-state and time-resolved optical spectroscopy, and response experiments combined with theoretical calculations demonstrate that distance-sensitive intercluster orbital interactions contribute to the exceptional collective optical responses. Such chiral supercrystals built from subnanoscale metal clusters with novel collective chiroptical responses would be useful in the fields of information storage and NIR optical devices.