We report a novel CsX-stripping mechanism that enables the efficient chemical transformation of nonluminescent CsPbX (X = Cl, Br, I) nanocrystals (NCs) to highly luminescent CsPbX NCs. During the transformation, CsPbX NCs dispersed in a nonpolar solvent are converted into CsPbX NCs by stripping CsX through an interfacial reaction with water in a different phase. This process takes advantage of the high solubility of CsX in water as well as the ionic nature and high ion diffusion property of CsPbX NCs, and produces monodisperse and air-stable CsPbX NCs with controllable halide composition, tunable emission wavelength covering the full visible range, narrow emission width, and high photoluminescent quantum yield (up to 75%). An additional advantage is that this is a clean synthesis as CsPbX NCs are converted into CsPbX NCs in the nonpolar phase while the byproduct of CsX is formed in water that could be easily separated from the organic phase. The as-prepared CsPbX NCs show enhanced stability against moisture because of the passivated surface. Our finding not only provides a new pathway for the preparation of highly luminescent CsPbX NCs but also adds insights into the chemical transformation behavior and stabilization mechanism of these emerging perovskite nanocrystals.

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All-inorganic perovskite light-emitting diodes (LEDs) reveal efficient luminescence with high color purity, but their modest brightness and poor stability are still critical drawbacks. Here, the luminescent efficiency and the stability of perovskite LEDs (PeLEDs) are boosted by antisolvent vapor treatment of CsPbBr 3 embedded in a dielectric polymer matrix of polyethylene oxide (PEO). A unique method is developed to obtain high quality CsPbBr 3 emitting layers with low defects by controlling their grain sizes. CsPbBr 3 in PEO matrix is post-treated with antisolvent of chloroform (CF), leading to microcrystals with a size of ≈5 µm along the in-plane direction with active emitting composite of 90%. A device based on CF post-treatment (CsPbBr 3 -PEO-CF) film displays a brightness of up to 51890 cd m −2 with an external quantum efficiency of 4.76%. CsPbBr 3 -PEO-CF PeLED still maintains 82% of its initial efficiency after 80 h continuous operation in ambient air, which indicates relatively good device stability. This work highlights that film quality is not only key to promoting fluorescence in CsPbBr 3 , but also to achieving higher performance PeLEDs.

Aims This study aimed to evaluate the prognostic effect of neutrophil‐to‐lymphocyte ratio (NLR) and platelet‐to‐lymphocyte ratio (PLR) for patients with breast cancer (BC). Methods A literature search was performed by searching medical databases. Basic characteristics and prognostic data were extracted from included studies. Primary outcomes, such as overall survival (OS) and disease‐free survival (DFS), were synthesized and compared. Subgroup analyses were performed according to pathology, geographical region, cut‐off value, and tumor progression. Results A total of 39 studies comprising 17079 BC patients were included in this meta‐analysis. Among them, 28 studies with 142 64 BC patients investigated predicting role of NLR for OS, showing elevated NLR were associated poor prognosis (hazard ratio [HR]: 1.78, 95% confidence interval [CI]: 1.49‐2.13, P < 0.001). Twenty‐seven studies containing 115 04 patients explored the role of NLR in predicting DFS, showing elevated NLR was associated with poor DFS with HR of 1.60 (95% CI: 1.42‐1.96, P < 0.001). Twelve studies explored the role of PLR in predicting OS, showing patients with higher PLR were associated with a significantly worse prognosis with a pooled HR of 1.32 (95% CI: 1.11‐1.57, P = 0.002). Eleven studies with 5013 patients shown patients with elevated PLR were associated shorter DFS (HR: 1.43, 95% CI: 1.09‐1.86, P = 0.009). Subgroup analyses shown a greater magnitude of association between NLR and OS in triple‐negative BC patients than in HER2‐positive ones. Conclusions Our study suggested that elevated NLR and PLR were associated with poor OS as well as high risk of recurrence for BC patients. Subgroup analyses confirmed the prognostic effect of NLR and PLR in HER2‐positive BC patients. As easily accessible parameters, NLR and PLR should be identified as useful biomarkers in the management of BC.

The shape anisotropy of nanoparticle building blocks is of critical importance in determining their packing symmetry and assembly directionality. While there has been extensive research on the effect of their overall geometric shapes, the importance of nanometer morphology details is not well-recognized or understood. Here we draw on shape-anisotropic gold triangular nanoprism building blocks synthesized based on a method we recently developed; besides the "large-scale" triangular prism shape (79.8 nm in side length and 22.0 nm in thickness), the prisms are beveled with their sides convexly enclosed by two flat {100} facets. We engineer the balance between electrostatic repulsion and entropically driven depletion attraction in the system to generate self-assemblies without or with the effect of the nanoscale beveling detail. A conventional, planar honeycomb (p-honeycomb) lattice forms with the triangular basal planes packed on the same plane at low depletion attraction, whereas an unexpected interlocking honeycomb (i-honeycomb) lattice and its "supracrystal" forms are assembled with additional close-paralleling of side facets at high depletion attraction. The i-honeycomb lattice renders all the metallic surfaces in close proximity and leads to a surface-enhanced Raman scattering signal nearly 5-fold higher than that in the p-honeycomb lattice and high sensitivity for detecting the model molecule Rhodamine 6G at a concentration as low as 10 M. Our study can guide future work in both nanoparticle synthesis and self-assembly; nanoscale geometrical features in anisotropic nanoparticles can be used as an important handle to control directional interactions for nonconventional ordered assemblies and to enrich diversity in self-assembly structure and function.