RESUMEN
The cross-coupling of aryl bromides with alkenes can provide access to diverse combinatorial chemical space. Two-component couplings between these partners are well-known, but three-component aryl-functionalizations of unactivated alkenes remain underdeveloped. In particular, the aryl-alkylation of unactivated alkenes would allow for rapid construction of molecular complexity and the expedient exploration of a pharmaceutically relevant and C(sp3)-rich structural landscape. Herein, we report a general approach toward the aryl-alkylation of alkenes through a triple radical sorting mechanism. Over the course of the reaction, a high energy aryl radical, a primary radical, and a hindered alkyl radical are simultaneously formed. Through mediation by a nickel-based catalyst, the three radicals are sorted into productive bond-forming pathways toward the efficient aryl-alkylation of alkenes. A wide range of electronically and sterically differentiated alkenes and aryl radical precursors can be used to access complex scaffolds. This method was further applied to the synthesis of highly substituted semisaturated fused heterocycles.
RESUMEN
Teleost fishes account for 96% of all fish species and exhibit a spectacular variety of body forms. Teleost lineages range from deep bodied to elongate (e.g., eels, needlefish), laterally compressed (e.g., ribbonfish) to globular (e.g., pufferfish), and include uniquely shaped lineages such as seahorses, flatfishes, and ocean sunfishes. Adaptive body shape convergence within fishes has long been hypothesized but the nature of the relationships between fish form and ecological and environmental variables remain largely unknown at the macroevolutionary scale. To facilitate the investigation of the interacting factors influencing teleost body shape evolution we measured eight functionally relevant linear traits on adult-sized specimens along with specimen mass. Linear measurements of standard length, maximum body depth, maximum fish width, lower jaw length, mouth width, head depth, minimum caudal peduncle depth, and minimum caudal peduncle width were taken in millimeters with calipers, or tape measures for oversized specimens. We measured these traits on a total of 16,523 specimens (1-3 specimens per species) at the Smithsonian National Museum of Natural History and took approximately 7000 person hours of data collection to complete. The data went through a three-step error-checking process to clean and validate the data and then species averages were calculated. We present the complete specimen data set, which encompasses approximately one-fifth of extant teleost species diversity, spanning ~90% of teleost families and ~96% of orders. The species and family names are compatible with the taxonomy used by FishBase and the order information with the phylogenetically informed taxonomy of Betancur-R and colleagues published in 2014. This dataset is licensed under Creative Commons CC0 1.0 Universal (CC0 1.0) but please cite this paper when using the data or a subset of it.
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Peces , Animales , FenotipoRESUMEN
BACKGROUND: Ulcerative colitis (UC) is an aggressive disease in the pediatric population and a cause of significant, lifelong morbidity. The aim of this study is to compare surgical complications in pediatric patients undergoing laparoscopic vs. open surgical treatment for UC. METHODS: We queried the Kids' Inpatient Database (KID) for all cases of UC undergoing surgical treatment in 2009 and 2012. We identified patients who received total colectomy without proctectomy (n=413) or total proctocolectomy (n=196) and performed univariate and multivariate analyses comparing laparoscopic vs. open procedures. RESULTS: In pediatric UC patients undergoing total colectomy without proctectomy, open procedures were associated with more complications than laparoscopic, including fluid and electrolyte disorders (40% vs. 28%), surgical wound dehiscence (6% vs. 2%), septicemia (18% vs. 2%), and gastrointestinal disorders (16% vs. 7%) among others, all P<0.05. Likewise, in patients with UC undergoing total proctocolectomy, there were more complications in open vs. laparoscopic technique, including increased transfusion requirements (25% vs. 7%, P=0.001) and significantly more gastrointestinal upset, including nausea, vomiting, and diarrhea (11% vs. 1%, P=0.003). In multivariate analysis, patients who underwent total colectomy with or without proctectomy had an increased risk of experiencing any complication when their procedure was performed in an open or non-elective fashion (all odds ratio >2.4; all P<0.001). CONCLUSIONS: The laparoscopic approach was associated with significantly lower rates of surgical complications in pediatric patients undergoing total colectomy with or without proctectomy for UC. These findings demonstrate that laparoscopic technique compares favorably, and may be preferable, to the open approach in selected pediatric patients with UC.
