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Scott M. Lanyon – 1st expert on this subject based on the ideXlab platform
Regular ArticleThe Impact of Parsimony Weighting Schemes on Inferred Relationships among Toucans and Neotropical Barbets (Aves: Piciformes)Molecular Phylogenetics and Evolution, 2000Co-Authors: F. Keith Barker, Scott M. LanyonAbstract:
The development of new schemes for weighting DNA sequence data for phylogenetic analysis continues to outpace the development of consensus on the most appropriate weights. The present study is an exploration of the similarities and differences between results from 22 character weighting schemes when applied to a study of Barbet and toucan (traditional avian families Capitonidae and Ramphastidae) phylogenetic relationships. The dataset comprises cytochrome b sequences for representatives of all toucan and Neotropical Barbet genera, as well as for several genera of Paleotropical Barbets. The 22 weighting schemes produced conflicting patterns of relationship among taxa, often with conflicting patterns each receiving strong bootstrap support. Use of multiple weighting schemes helped to identify the source within the dataset (codon position, transitions, transversions) of the various putative phylogenetic signals. Importantly, some phylogenetic hypotheses were consistently supported despite the wide range of weights employed. The use of phylogenetic frameworks to summarize the results of these multiple analyses proved very informative. Relationships among Barbets and toucans inferred from these data support the paraphyly of the traditional Capitonidae. Additionally, these data support paraphyly of Neotropical Barbets, but rather than indicating a relationship between Semnornis and toucans, as previously suggested by morphological data, most analyses indicate a basal position of Semnornis within the Neotropical radiation. The cytochrome b data also allow inference of relationships among toucans. Supported hypotheses include Ramphastos as the sister to all other toucans, a close relationship of Baillonius and Pteroglossus with these two genera as the sister group to an (Andigena, Selenidera) clade, and the latter four genera as a sister group to Aulacorhynchus.
reexamination of Barbet monophyly using mitochondrial dna sequence dataThe Auk, 1994Co-Authors: Scott M. Lanyon, John G HallAbstract:
ABSTRACr.-An 888-base-pair segment of the mitochondrial cytochrome-b gene was sequenced for New World Barbets, Old World Barbets, toucans, and several outgroup taxa. Toucans were consistently identified as the sister taxon of the New World Barbets by a variety of analyses. These data are fundamentally different from earlier morphological analyses and the DNA-DNA hybridization study of these same taxa. Our results provide an independent confirmation of relationships proposed in both the morphological and molecular studiesthat New World Barbets and toucans are sister taxa with respect to Old World Barbets. Received 19 June 1992, accepted 25 November 1992. TRADITIONAL MORPHOLOGICAL analyses have disagreed on the phylogenetic relationships among the Barbets (Capitonidae), a pantropical assemblage of frugivorous birds, traditionally placed in the Piciformes with woodpeckers,
Robert G. Moyle – 2nd expert on this subject based on the ideXlab platform
Phylogenetics of Barbets (Aves: Piciformes) based on nuclear and mitochondrial DNA sequence data.Molecular Phylogenetics and Evolution, 2003Co-Authors: Robert G. MoyleAbstract:
Abstract A combination of nuclear (β-fibrinogen intron 7; 938 bp) and mitochondrial (cytochrome b; 1045 bp) DNA sequence data analyzed with model-based phylogenetic methods yields a hypothesis of Barbet and toucan relationships supported by high Bayesian posterior probabilities and several synapomorphic indels in the nuclear intron data. The basal topology differs from previous morphology and mitochondrial DNA sequence based hypotheses, but is consistent with DNA–DNA hybridization results. The mitochondrial DNA sequence data provide resolution at the tips of the tree, but when analyzed alone, yield a different basal topology than the combined data. However, the basal nodes in the mitochondrial-based tree have little statistical support. Combined data analysis produced strong statistical support at basal nodes and a relatively simple geographic structure. Barbets from each of the three tropical regions are monophyletic, but the Old World Barbets are paraphyletic. The African and New World clades are sister taxa, and the Asian clade is basal. This geographic structure indicates that similarities in plumage, voice, and behavior between Gymnobucco and Calorhamphus are convergent. The data are not conclusive, but suggest paraphyly of the New World Barbets. Only 4% of the Bayesian posterior distribution unites Semnornis with the other New World Barbets.
Alan Tyroch – 3rd expert on this subject based on the ideXlab platform
Small bowel obstructions following the use of barbed suture: a review of the literature and analysis of the MAUDE databaseSurgical Endoscopy, 2020Co-Authors: Benjamin Clapp, William Klingsporn, Carlos Lodeiro, Ellen Wicker, Loyd Christensen, Robert Jones, Alan TyrochAbstract:
Background Barbed suture has been adopted across all surgical specialties. One of the infrequent complications seen with the use of barbed suture is small bowel obstructions (SBOs). In this study, we perform a review of the literature and the Manufacturer and User Facility Device Experience Database (MAUDE) to characterize SBOs after the use of barbed sutures in a variety of operative procedures. Methods A review of the literature was performed by searching PubMed and Ovid. We used the search terms: “barbed,” “suture,” “bowel,” and “obstructions.” For each case report, we examined the initial surgical procedure, type of barbed suture used, the type of complication, the time to complication, the presentation, and the type of operative interventions required. We did the same with the MAUDE database. Results Our review of the literature revealed 18 different cases of SBO secondary to the use of barbed suture. The four most common procedures, with a total of four cases each, were inguinal hernia procedures, myomectomy, hysterectomy, and pelvic floor reconstructive procedures. The average time of presentation to SBO was found to be 26.3 days post-op (1–196 days). A total of 16 patients (88.9%) presented with abdominal pain. Other common complaints included vomiting (33.3%), abdominal distension (27.8%), oral intolerance (22.2%), and constipation (16.7%). A total of 5 cases were also found to have a possible volvulus on computed tomography (CT), and 2 cases were reported to have strangulation. The MAUDE database had 14 cases reporting on obstruction. Conclusions Surgeons should have a high index of suspicion for SBO if a patient presents with obstructive symptoms after a surgery that used barbed suture. This will often present as a mesenteric volvulus on CT. These particular SBOs require operative exploration, with laparoscopy being successful in the majority of cases.
small bowel obstructions following the use of barbed suture a review of the literature and analysis of the maude databaseSurgical Endoscopy and Other Interventional Techniques, 2020Co-Authors: Benjamin Clapp, William Klingsporn, Carlos Lodeiro, Ellen Wicker, Loyd Christensen, Robert Paul Jones, Alan TyrochAbstract:
Barbed suture has been adopted across all surgical specialties. One of the infrequent complications seen with the use of barbed suture is small bowel obstructions (SBOs). In this study, we perform a review of the literature and the Manufacturer and User Facility Device Experience Database (MAUDE) to characterize SBOs after the use of barbed sutures in a variety of operative procedures.