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Abstract: The oxovanadium phosphonates (VO(P204)2 and VO(P507)2) activated by various alkylaluminums (AlR3, R=Et, i-Bu, n-Oct; HAlR2, R=Et, i-Bu) were examined in butadiene (Bd) polymerization. Both VO(P204)2 and VO(P507)2 showed higher activity than those of classical vanadium-based catalysts (e.g. VOCl3, V(acac)3). Among the examined catalysts, the VO(P204)2/Al(Oct)3 system (I) revealed the highest catalytic activity, giving the poly(Bd) bearing M n of 3.76×104 g/mol, and M w/M n ratio of 2.9, when the [Al]/[V] molar ratio was 4.0 at 40°C. The polymerization rate for I is of the first order with respect to the concentration of monomer. High thermal stability of I was found, since a fairly good catalytic activity was achieved even at 70°C (polymer yield>33%); the M n value and M w/M n ratio were independent of polymerization temperature in the range of 40–70°C. By IR and DSC, the poly(Bd)s obtained had high 1,2-unit content (>65%) with atactic configuration. The 1,2-unit content of the polymers obtained by I was nearly unchanged, regardless of variation of reaction conditions, i.e. [Al]/[V], ageing time, and reaction temperature, indicating the high stability of stereospecificity of the active sites. [Copyright &y& Elsevier]

Single crystal Pr(BO2)3 with centimeter size was grown successfully by a flux method using 3Li2CO3-2H3BO3 as a flux. The absorption spectrum, emission spectrum, and luminescence lifetime of the Pr(BO2)3 crystal were measured. The crystal has a relatively large absorption cross section and full widths at half maximum (FWHM), which is advantageous for energy absorption from a pumping source. The spectrum parameters were calculated based on Judd–Ofelt (J-O) theory, and the effective J-O parameters were determined to be: Ω2 = 37.47 × 1020 cm2, Ω4 = 6.80 × 1020 cm2, and Ω6 = 1.05 × 1020 cm2. Furthermore, the emission cross section for the 3P0 →3F2 transition at 650 nm was calculated to be 13.6 × 10−19 cm2. The fluorescence lifetime of the 3P0 level was obtained to be 4.5 ns. The Raman spectrum of the crystal was also analyzed in detail. Physical properties such as thermal and chemical stability, hardness, and cleavage properties were explored. The refractive index and electronic structure were calculated by the first-principles method. • A stoichiometric laser crystal Pr(BO2)3 with a centimeter size was grown for the first time. • Physical and optical properties were explored, and the optical parameters were calculated by Judd–Ofelt theory. • Optical properties of Pr(BO2)3 crystal demonstrate a good potential for red laser applications. • The first-principles calculations are carried out. [ABSTRACT FROM AUTHOR]

This study was aimed at constructing a pyroptosis-related signature for prostate cancer (PCa) and elucidating the prognosis and immune landscape and the sensitivity of immune checkpoint blockade (ICB) therapy in signature-define subgroups of PCa. We identified 22 differentially expressed pyroptosis-related genes in PCa from The Cancer Genome Atlas (TCGA) database. The pyroptosis-related genes could divide PCa patients into two clusters with differences in survival. Seven genes were determined to construct a signature that was confirmed by qRT-PCR to be closely associated with the biological characteristics of malignant PCa. The signature could effectively and independently predict the biochemical recurrence (BCR) of PCa, which was validated in the GSE116918 and GSE21034. We found that patients in the high-risk group were more prone to BCR and closely associated with high-grade and advanced-stage disease progression. Outperforming clinical characteristics and nine published articles, our signature demonstrated excellent predictive performance. The patients in the low-risk group were strongly related to the high infiltration of various immune cells including CD8+ T cells and plasma B cells. Furthermore, the high-risk group with higher TMB levels and expression of immune checkpoints was more likely to benefit from immune checkpoint therapy such as PD-1 and CTLA-4 inhibitors. The sensitivity to chemotherapy, endocrine, and targeted therapy showed significant differences in the two risk groups. Our signature was a novel therapeutic strategy to distinguish the prognosis and guide treatment strategies. [ABSTRACT FROM AUTHOR]