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Photinia Lindl. sensu lato including Photinia, Pourthiaea, Stranvaesia and Aronia, occurs primarily in eastern and southeastern Asia, eastern North America, and Central America. However, generic circumscription within the group has been a taxonomic problem. Phylogenetic analyses were conducted in Photinia sensu lato and several related genera based on two chloroplast DNA regions and nrITS sequences, separately and in combination, and nine non-molecular characters were plotted onto a phylogeny based on the combined molecular data. All phylogenetic trees produced indicated that Stranvaesia should be merged into Photinia, while Pourthiaea and Aronia should be delimited as two separate genera. Ph. davidsoniae and Ph. nussia form a separate clade in our consensus trees and Ph. davidsoniae is speculated to have originated from hybridization between Photinia and some other genus of Pyrinae characterized by spines on the stem, but the specific hybrid origin cannot be inferred in detail due to lack of samples included in our data. The relationships among two taxa of Photinia from Mexico and Central America and species distributed in eastern Asia are also discussed. Ph. microcarpa subsp. hintonii var. hintonii is sister to species in eastern Asia is supported, but with weak support, while the position of a second taxon from Mexico, whose identity is uncertain, is unresolved, indicating the need for further taxonomic and biogeographic studies of these species. Incongruence between chloroplast and nuclear data supports the hypothesis of a hybrid origin of the monospecific genus Heteromeles, with a recent ancestor of extant Photinia as the probable male parent. [ABSTRACT FROM AUTHOR]

Purpose: Accurate diagnosis of small bowel obstruction (SBO) remains challenging. The evidence of the diagnostic accuracy of ultrasound varies among studies, with reporting sensitivity ranging from 82 % to 100 % and specificity ranging from 54 % to 100 %. The aim of our study is to perform a systematic review and meta-analysis to investigate the accuracy of ultrasound for diagnosing SBO.Method: The PubMed, EMBASE, Cochrane Library, Web of Science, and Scopus databases were searched from database inception to March 2020. Randomized controlled trials, quasi randomized studies, and prospective or retrospective cohort studies that evaluated the diagnostic performance of ultrasound for the diagnosis of bowel obstruction in adult patients (age ≥ 16 years) were eligible. The QUADAS-2 tool was used to assess the quality of the included studies. The pooled sensitivities, specificities were analyzed using a bivariate random-effects model. (PROSPERO ID: CRD42020170010).Results: Fifteen studies, with most rating as a moderate risk of bias, met the inclusion criteria. The pooled sensitivity and specificity were 92 % (95 % CI: 89%-95%) and 93 % (95 % CI: 85%-97%), respectively. Subgroup analysis revealed no significant differences in sensitivity when ultrasound was performed on different continents, in different settings, and under different reference standards. However, the specificity was significantly lower when ultrasound was performed in the North America, in the emergency department, and when computed tomography was used as the only reference standard.Conclusions: Overall, ultrasound is a highly sensitive and specific tool for the diagnosis of SBO. Using ultrasound to rule in patients with SBO should be used with caution, as variations in the specificity were observed in different study setting, operators from different continents and reference standards used. [ABSTRACT FROM AUTHOR]