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Examining the pollination biology of plant species is not only crucial for enhancing our understanding of their reproductive biology, but also essential for elucidating their adaptation and evolutionary history. Here, we investigated the breeding system and pollination biology of two closely related species in Actaea. The flower of A. purpurea is unique in the genus with purple and chartaceous (paper-like) sepals, fewer stamens with yellow anthers and purple filaments. Through three seasons of field observation and exclusion experiments, we determined that A. purpurea was primarily pollinated by a hornet species, Vespa bicolor , which also served as the most efficient pollinator. In contrast, A. japonica was primarily pollinated by large flies. Actaea purpurea exhibited a significantly higher cumulative nectar volume than A. japonica , which could be a crucial factor in attracting V. bicolor. A control experiment further demonstrated that removing the nectar leaf (petal) significantly decreased the visiting frequency of V. bicolor. Breeding system studies revealed that both species were self-compatible, yet they primarily underwent outcrossing in natural habitats. Our study presents a compelling case of possible pollinator shift in A. purpurea accompanied by morphological divergence. A more in-depth investigation of this system would offer crucial insights into the extent to which pollinators are involved in the plant speciation process and whether they contribute to reproductive isolation between closely related species. [ABSTRACT FROM AUTHOR]

Background: Left bundle branch block (LBBB) and atrial fibrillation (AF) are commonly coexisting conditions. The impact of LBBB on catheter ablation of AF has not been well determined. This study aims to explore the long‐term outcomes of patients with AF and LBBB after catheter ablation. Methods: Forty‐two patients with LBBB of 11,752 patients who underwent catheter ablation of AF from 2011 to 2020 were enrolled as LBBB group. After propensity score matching in a 1:4 ratio, 168 AF patients without LBBB were enrolled as non‐LBBB group. Late recurrence and a composite endpoint of stroke, all‐cause mortality, and cardiovascular hospitalization were compared between the two groups. Results: Late recurrence rate was significantly higher in the LBBB group than that in the non‐LBBB group (54.8% vs. 31.5%, p =.034). Multivariate analysis showed that LBBB was an independent risk factor for late recurrence after catheter ablation of AF (hazard ratio [HR] 2.19, 95% confidence interval [CI] 1.09–4.40, p =.031). LBBB group was also associated with a significantly higher incidence of the composite endpoint (21.4% vs. 6.5%, HR 3.98, 95% CI 1.64–9.64, p =.002). Conclusions: LBBB was associated with a higher risk for late recurrence and a higher incidence of composite endpoint in the patients underwent catheter ablation. [ABSTRACT FROM AUTHOR]

SUMMARY: Rhodiola L. is a genus that has undergone rapid radiation in the mid‐Miocene and may represent a typic case of adaptive radiation. Many species of Rhodiola have also been widely used as an important adaptogen in traditional medicines for centuries. However, a lack of high‐quality chromosome‐level genomes hinders in‐depth study of its evolution and biosynthetic pathway of secondary metabolites. Here, we assembled two chromosome‐level genomes for two Rhodiola species with different chromosome number and sexual system. The assembled genome size of R. chrysanthemifolia (2n = 14; hermaphrodite) and R. kirilowii (2n = 22; dioecious) were of 402.67 and 653.62 Mb, respectively, with approximately 57.60% and 69.22% of transposable elements (TEs). The size difference between the two genomes was mostly due to proliferation of long terminal repeat‐retrotransposons (LTR‐RTs) in the R. kirilowii genome. Comparative genomic analysis revealed possible gene families responsible for high‐altitude adaptation of Rhodiola, including a homolog of plant cysteine oxidase 2 gene of Arabidopsis thaliana (AtPCO2), which is part of the core molecular reaction to hypoxia and contributes to the stability of Group VII ethylene response factors (ERF‐VII). We found extensive chromosome fusion/fission events and structural variations between the two genomes, which might have facilitated the initial rapid radiation of Rhodiola. We also identified candidate genes in the biosynthetic pathway of salidroside. Overall, our results provide important insights into genome evolution in plant rapid radiations, and possible roles of chromosome fusion/fission and structure variation played in rapid speciation. [ABSTRACT FROM AUTHOR]