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Abstract Iminophosphoranes with the general formula (R3P═NR′) have great potential in synthetic chemistry as valuable precursors/intermediates in organic synthesis or as building blocks for various organic compounds. However, the synthetic approaches and conditions to prepare iminophosphoranes are still poorly understood, limiting the utility of this chemistry for organic materials. In this article, a simple and efficient synthesis of previously unattainable poly(arylene iminophosphoranes) is reported. The azide-phosphine Staudinger polycondensation is used, and the reaction conditions are carefully studied, including consideration of light and air, the influence of solvent and temperature, and investigation of the electronic and steric effects of multiazides. The newly defined reaction conditions appear to be highly versatile, allowing the use of both electron-rich and electron-deficient arylazides for reaction with phosphines to synthesize a library of poly(arylene iminophosphorane) networks that exhibit exceptional thermal and oxidative stability. Interestingly, despite the ylidic-form of the iminophosphorane linkage as shown by theoretical calculations, these newly developed poly(arylene-iminophosphorane) networks exhibit semiconducting properties, such as absorption band edges up to 800 nm and optical band gaps in the range of 1.70 to 2.40 eV. Finally, we demonstrate the broad applicability of these polymers by processing them into glassy films, creating foam-like structures and synthesizing metallo-polymer hybrids.

This study explores the influence of metaverse experiences and social interaction on tourists’ engagement and satisfaction in virtual tourism environments. In the digital era, the metaverse provides an immersive, interactive platform for tourism, allowing users to experience destinations virtually. Drawing from theoretical frameworks on tourism experience, the metaverse experience in this study is categorized into three core dimensions: presence and telepresence, immersion, interactivity and vividness. Additionally, social interaction, which encompasses peer-to-peer engagement and community building within virtual settings, is examined as a mediating factor that may enhance the overall tourism experience. Data was collected from 400 tourists in Thailand and analyzed using structural equation modeling (SEM) to test two primary hypotheses: first, that the metaverse has a direct positive influence on tourism experience, and second, that social interaction mediates this relationship. Results support both hypotheses, demonstrating that the metaverse significantly enhances tourism experience through its immersive and interactive features, with social interaction further amplifying this effect as a partial mediator. These findings suggest valuable implications for tourism practitioners and developers of virtual tourism platforms, emphasizing the need to integrate high-quality, socially engaging digital experiences. The study contributes to understanding how metaverse technology, combined with social engagement, can enrich virtual tourism and align with Thailand’s broader digital tourism initiatives.

Taylorella equigenitalis is the causative agent of sexually transmitted contagious equine metritis. Infections manifest as cervicitis, vaginitis and endometritis and cause temporary infertility and miscarriages of mares. While previous studies have analyzed this organism for various parameters, the evolutionary dynamics of this pathogen, including the emergence of antibiotic resistance, remains unresolved. The aim of this study was to isolate contemporary strains, determine their genome sequences, evaluate their antibiotic resistance and compare them with other strains. We determined nine complete whole genome sequences of T. equigenitalis strains, mainly from samples collected from Kladruber horses in the Czech Republic. While T. equigenitalis strains from Kladruby isolated between 1982 and 2018 were inhibited by streptomycin, contemporary strains were found to be resistant to streptomycin, suggesting the recent emergence of this mutation. In addition, we used the collection dates of Kladruber horse strains to estimate the genome substitution rate, which resulted in a scaled mean evolutionary rate of 6.9×10-7 substitutions per site per year. Analysis with other available T. equigenitalis genome sequences (n = 18) revealed similarity of the Czech T. equigenitalis genomes with the Austrian T. equigenitalis genome, and molecular dating suggested a common ancestor of all analyzed T. equigenitalis strains from 1.5-2.6 thousand years ago, dating to the first centuries A.D. Our study revealed a recently emerged streptomycin resistance in T. equigenitalis strains from Kladruber horses, emphasizing the need for antibiotic surveillance and alternative treatments. Additionally, our findings provided insights into the pathogen's evolution rate, which is important for understanding its evolution and preparing preventive strategies.

Background: Immunotherapy based on checkpoint inhibition is widely used in the treatment of metastatic renal cell carcinoma (RCC); however, predictive and prognostic biomarkers are yet to be explored. The objective of this study was to evaluate the prognostic value of the hemoglobin, albumin, lymphocyte, platelet (HALP) score in metastatic RCC patients receiving nivolumab. Methods: We enrolled 149 individuals (including 38 females) with a median age of 62 years, who were treated with nivolumab (at a dosage of 240 mg biweekly or 480 mg every 28 days) following progression on at least one tyrosine kinase inhibitor (TKI) between 2016 and 2024. The study population was dichotomized by the median HALP score (27.53), which was calculated as hemoglobin (g/L) × albumin (g/L) × absolute lymphocyte count/platelets (g/L) at immunotherapy initiation. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan–Meier method, with differences analyzed via a log-rank test. A multivariate Cox proportional hazards model was utilized for evaluation of the prognostic value of performance status, lactate dehydrogenase (LDH) levels, and HALP score. Results: At a median follow-up of 31.1 months, 122 patients had progressed on nivolumab and 87 had died. Poor performance status was associated with significantly worse PFS and OS (HR 0.20 and 0.14, respectively). Survival was worse in individuals with an LDH level higher than 1.5 times the normal range compared to those with lower LDH values (HR 0.45 for PFS and HR 0.41 for OS). Patients with low HALP scores had shorter PFS (HR 0.69) and OS (HR 0.58) versus patients with high HALP scores. In the multivariate analysis, the independent prognostic value of the HALP index for OS was revealed in a metastatic clear-cell RCC (ccRCC) population. Conclusions: The HALP score determined before nivolumab initiation as the second or third line of treatment is an independent prognostic factor of OS in metastatic ccRCC patients. Prospective validation could lead to the incorporation of this index into prognostic models for patients with RCC.