Photocycle and flash-induced proton release and uptake were investigated for bacteriorhodopsin mutants in which Asp-85 was replaced by Ala, Asn, or Glu; Asp-212 was replaced by Asn or Glu; Asp-115 was replaced by Ala, Asn, or Glu; Asp-96 was replaced by Ala, Asn, or Glu; and Arg-82 was replaced by Ala or Gln in dimyristoylphosphatidylcholine/3- [(3-cholamidopropyl)dimethylammonio]-l-propanesulfonate miceiles at pH 7.3. In the Asp-85 -Ala and Asp-85 --Asn mutants, the absence of the charged carboxyl group leads to a blue chromophore at 600 and 595 nm, respectively, and lowers the pK of the Schiff base deprotonation to 8.2 and 7, respectively, suggesting a role for Asp-85 as counterion to the Schiff base. The early part of the photocycles of the Asp-85 -* Ala and Asp-85 -* Asn mutants is strongly perturbed; the formation of a weak M-like intermediate is slowed down about 100-fold over wild type. In both mutants, proton release is also slower but dearly precedes the rise of M. The amplitude of the early (<0.2 ps) reversed photovoltage component in the Asp-85 -* Asn mutant is very large, and the net charge displacement is close to zero, indicating proton release and uptake on the cytoplasmic side of the membrane. The data suggest an obligatory role for Asp-85 in the efficient deprotonation of the Schiff base and in the proton release phase, probably as proton acceptor. In the Asp-212 -* Asn mutant, the rise of the absorbance change at 410 nm is slowed down to 220 Ls, its amplitude is small, and the release of protons is delayed to 1.9 ms. The absorbance changes at 650 nm indicate perturbations in the early time range with a slow K intermediate. Thus Asp-212 also participates in the early events of charge translocation and deprotonation of the Schiff base. In the Arg-82 -Gln mutant, no net transient proton release was observed, whereas, in the Arg-82 Ala mutant,, uptake and release were reversed. The pK shift of the purple-to-blue transition in the Asp-85 --Glu, Arg-82-Ala, and Arg-82 --Gin mutants and the similarity in the photocycle and photoelectrical signals of the Asp-85 -Ala, Asp-85 --Asn, and Asp-212 --Asn mutants suggest the interaction between Asp-85, Arg-82, Asp-212, and the Schiff base as essential for proton release.Site-directed mutagenesis has shown and Asp-212 to be essential for proton translocation by bacteriorhodopsin (bR) (1). The very low activity in mutants Asp-96 -+ Ala (D96A) and Asp-96 -* Asn (D96N) at pH 7 is due to a markedly slowed-down decay of the photocycle intermediate M and the associated charge movement (2-5). was concluded to be the internal proton donor for the reprotonation of the Schiff base (SB) leading to the decay of M (3, 4). Fourier-transform infrared spectroscopy has revealed the protonation states of Asp-85, Asp-96, Asp-115, and Asp-212 in the K, L, and M intermediates and provided clues to the time course of proton transfer (6, 7). The data suggest that Asp-85 and Asp-212 are deprotonated in the ground state and become protonated in the L -* M transition (6). A...

The use of acoustic Doppler current profilers (ADCP) for discharge measurements and three‐dimensional flow mapping has increased rapidly in recent years and has been primarily driven by advances in acoustic technology and signal processing. Recent research has developed a variety of methods for processing data obtained from a range of ADCP deployments and this paper builds on this progress by describing new software for processing and visualizing ADCP data collected along transects in rivers or other bodies of water. The new utility, the Velocity Mapping Toolbox (VMT), allows rapid processing (vector rotation, projection, averaging and smoothing), visualization (planform and cross‐section vector and contouring), and analysis of a range of ADCP‐derived datasets. The paper documents the data processing routines in the toolbox and presents a set of diverse examples that demonstrate its capabilities. The toolbox is applicable to the analysis of ADCP data collected in a wide range of aquatic environments and is made available as open‐source code along with this publication. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.

Temporal trends suggest the existence of three unrelated types of melanoma: type I, thick melanomas, with stable incidence; type II, thin melanoma with a steady and important increase in incidence, mainly located on the trunk; and type III, melanoma with a slower increase in incidence, mainly located on the head and neck region.

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Compound meander bends with multiple lobes of maximum curvature are common in actively evolving lowland rivers. Interaction among spatial patterns of mean flow, turbulence, bed morphology, bank failures and channel migration in compound bends is poorly understood. In this paper, acoustic Doppler current profiler (ADCP) measurements of the three‐dimensional (3D) flow velocities in a compound bend are examined to evaluate the influence of channel curvature and hydrologic variability on the structure of flow within the bend. Flow structure at various flow stages is related to changes in bed morphology over the study timeframe. Increases in local curvature within the upstream lobe of the bend reduce outer bank velocities at morphologically significant flows, creating a region that protects the bank from high momentum flow and high bed shear stresses. The dimensionless radius of curvature in the upstream lobe is one‐third less than that of the downstream lobe, with average bank erosion rates less than half of the erosion rates for the downstream lobe. Higher bank erosion rates within the downstream lobe correspond to the shift in a core of high velocity and bed shear stresses toward the outer bank as flow moves through the two lobes. These erosion patterns provide a mechanism for continued migration of the downstream lobe in the near future. Bed material size distributions within the bend correspond to spatial patterns of bed shear stress magnitudes, indicating that bed material sorting within the bend is governed by bed shear stress. Results suggest that patterns of flow, sediment entrainment, and planform evolution in compound meander bends are more complex than in simple meander bends. Moreover, interactions among local influences on the flow, such as woody debris, local topographic steering, and locally high curvature, tend to cause compound bends to evolve toward increasing planform complexity over time rather than stable configurations. Copyright © 2016 John Wiley & Sons, Ltd.