The present research work focuses on bismuth vanadate (BiVO4) thin films deposited on FTO-coated glass electrodes through the spin-coating technique, and discusses the influence of different film morphologies (dense and porous) on the physicochemical properties and photoelectrochemical (PEC) performance of the as-prepared photoanodes, for the water splitting reaction. The surface recombination phenomenon, which is one of the main issues of BiVO4, has been quantified by means of two distinct approaches: transient photocurrent measurements and electrochemical impedance spectroscopy (EIS). This phenomenon has resulted to be higher in the porous material, thus a poorer performance has been observed than in the dense material. In order to increase the BiVO4 efficiency, a cobalt phosphate (CoPi) catalyst has been photo-electrodeposited onto the best BiVO4 electrode, employing an optimized technique and a photocurrent of up to 3 mA/cm 2 at 1.23 V vs. RHE under neutral pH and 1 sun irradiation (100 mW/cm 2) has been achieved. The charge transfer kinetics of the BiVO4 photoanodes, with and without CoPi, has also been quantified. The beneficial effect of this water oxidation catalyst, as well as the influence of the preparation method on the uniformity of the film and on its actual performance, is discussed in view of its prospective application in a real PEC device.

Resting state electroencephalographic (EEG) rhythms do not deteriorate with the increase of white matter vascular lesion in amnesic mild cognitive impairment (MCI) subjects [1], although white matter is impaired along Alzheimer's disease (AD). Here we tested whether this is true even in AD subjects. Closed-eye resting state EEG data were recorded in 40 healthy elderly (Nold), 96 amnesic MCI, and 83 AD subjects. White matter vascular lesions were indexed by magnetic resonance imaging recorded in the MCI and AD subjects (about 42% of cases following ADNI standards). The MCI subjects were divided into two sub-groups based on the median of the white matter lesion, namely MCI+ (people with highest vascular load; n = 48) and MCI- (people with lowest vascular load; n = 48). The same was true for the AD subjects (AD+, n = 42; AD-, n = 41). EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha1 (8-10.5 Hz), alpha2 (10.5-13 Hz), beta1 (13-20 Hz), beta2 (20-30 Hz), and gamma (30-40 Hz). LORETA software estimated cortical EEG sources. When compared to Nold group, MCI and AD groups showed well known abnormalities of delta and alpha sources. Furthermore, amplitude of occipital, temporal, and limbic alpha 1 sources were higher in MCI+ than MCI- group. As a novelty, amplitude of occipital delta sources was lower in AD+ than AD- group. Furthermore, central, parietal, occipital, temporal, and limbic alpha sources were higher in amplitude in AD+ than AD- group. Amplitude of these sources was correlated to global cognitive status (i.e., Mini Mental State Evaluation score). These results suggest that in amnesic MCI and AD subjects, resting state posterior delta and alpha EEG rhythms do not deteriorate with the increase of white-matter vascular lesion. These rhythms might be more sensitive to AD neurodegenerative processes and cognitive status rather than to concomitant lesions to white matter.

Several authors have suggested that mantle convection is primarily resisted by strong subduction zones, which if true implies small or even negative values of the exponent β in the Nusselt number/Rayleigh number relation Nu ∼ Ra β. To evaluate this hypothesis, we use the boundary element method (BEM) to study the energetics of subduction in a two-dimensional system comprising two purely viscous plates, a subducting plate (SP) and an overriding plate (OP), immersed in an infinitely deep ambient fluid beneath a free-slip surface. The negative buoyancy of the slab is the only driving force. The principal quantity

This work uses the boundary element method (BEM) to explore the dynamics of subduction of a dense lithospheric plate (subducting plate, SP) beneath an overriding plate (OP). For simplicity, the model is two dimensional, the plates are purely viscous, and the ambient fluid is infinitely deep. The negative buoyancy of the slab is the only driving force of the system. First, we study the SP kinematics focusing on two characteristic instantaneous velocities: the convergence speed (VConv) of the descending slab and the horizontal plate speed (USP) of the flat portion of the SP. We find that VConv is entirely controlled by the slab's geometry, by the width of the lubrication layer d2 separating the SP and the OP, and by the SP's flexural stiffness St. Turning to USP, we find that this parameter depends not only on d2 and St but also on the lengths LSP and LOP of the two plates. The dependence of USP on LSP is exactly logarithmic, both with and without an OP. Next, we explore the deformation of the OP, which occurs by a combination of extension/compression and bending. The OP deformation is compression dominated close to the trench and bending dominated along the remaining portion of the OP that undergoes significant deformation. For a positively buoyant OP, backarc extension is also observed. Finally, we estimate the subduction interface viscosity ηSI of the central Aleutian subduction zone, running our BEM model with the appropriate geometry according to Lallemand et al. (2015, https://doi.org/10.1029/2005GC000917). We find ηSI =  (0.96–1.72) ×1020 Pa s.