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Floodplain water bodies provide habitat to diversified ecological communities. Floodplains are also among the most impacted aquatic ecosystems. While the link between the lateral connectivity of floodplain sites to the main channel and their plant, fish and invertebrate communities has been well established, detailed information on chemical characteristics and particularly on trace metal spatial distribution and partitioning is scarce. The aim of this study was to examine the link between the lateral connectivity and physico-chemical variables, their trace metal concentrations and partitioning as well as the upstream-downstream gradient of these parameters. In connected and disconnected water bodies of the Rhône River upstream and downstream of the city of Lyon, we measured major ions, dissolved organic carbon, trace metal concentrations (Al, Cr, Ni, Cu, Zn, Cd, Pb and U) in water, suspended particulate matter (SPM) and sediment. The results revealed a clear difference between connected and disconnected water bodies. pH, SPM, Na + , and NO 3 - concentrations were lower in disconnected sites while conductivity, DOC, Ca 2+ and Mg 2+ were higher. Conductivity and a part of the major ion concentrations increased in the downstream sections. Trace metal concentrations and partitioning varied between connected and disconnected sites. In the dissolved fraction, trace metal concentrations were higher in connected sites. In the surface sediment, concentrations were higher in disconnected sites for the majority of metals. The upstream-downstream gradient was less important than the connected-disconnected gradient. Only three metals in the dissolved fraction (Cu, Cd and Pb) showed a clear increase in downstream sections. Overall, the study shows that the functioning of floodplains produces strong spatial patterns concerning the concentrations and partitioning of trace metals. These findings improve our understanding of trace metal biogeochemistry in floodplains and have important applications for floodplain restoration projects., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Objective: To describe baseline characteristics, initial postoperative refractive errors, operative complications, and magnitude of the intraocular lens (IOL) prediction error for refractive outcome in children undergoing lensectomy largely in North America., Design: Prospective registry study of children from birth to <13 years of age who underwent lensectomy for any reason within 45 days preceding enrollment., Participants: Total of 1266 eyes of 994 children; 49% female and 59% white., Methods: Measurement of refractive error, axial length, and complete ophthalmic examination., Main Outcome Measures: Eye and systemic associated conditions, IOL style, refractive error, pseudophakic refraction prediction error, operative and perioperative complications., Results: Mean age at first eligible lens surgery was 4.2 years; 337 (34%) were <1 year of age. Unilateral surgery was performed in 584 children (59%). Additional ocular abnormalities were noted in 301 eyes (24%). An IOL was placed in 35 of 460 eyes (8%) when surgery was performed before 1 year of age, in 70 of 90 eyes (78%) from 1 to <2 years of age, and in 645 of 716 eyes (90%) from 2 to <13 years of age. The odds of IOL implantation were greater in children ≥2 years of age than in those <2 years of age (odds ratio = 29.1; P < 0.001; 95% confidence interval: 19.6-43.3). Intraoperative complications were reported for 69 eyes (5%), with the most common being unplanned posterior capsule rupture in 14 eyes, 10 of which had an IOL placed. Prediction error of the implanted IOL was <1.00 diopter in 54% of eyes, but >2.00 diopters in 15% of eyes., Conclusions: Lensectomy surgery was performed throughout childhood, with about two-thirds of cases performed after 1 year of age. Initial surgery seemed safe, with a low complication rate. IOL placement was nearly universal in children 2 years of age and older. The immediate postoperative refraction was within 1 diopter of the target for about one-half of eyes., Competing Interests: No conflicting relationships exist for any author., (Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)