Sardinella ventura n. sp. (Actinopterygii: Clupeiformes: Clupeidae), a new sardine from Mauritius

The new sardine Sardinella ventura n. sp. (Teleostei: Clupeiformes: Clupeidae) is described on the basis of 10 specimens collected from Mauritius. The new species is most similar to Sardinella dayi Regan 1917 in having non-deciduous scales with pores and discontinuous striae, a dark spot on the dorsal-fin origin, the pelvic fin with 8 rays, and similar number of gill rakers, in addition to very similar numbers of keeled scutes. However, the new species is distinguished from S. dayi by having a shorter caudal peduncle [6.2–7.6% SL (mean 7.0%) vs. 8.2–12.0% (9.2%) in S. dayi], larger eye [8.4–9.9% (9.0%) vs. 6.8–8.0% (7.4%)] and orbit [9.6–12.3% (10.7%) vs. 8.5–10.2% (9.3%)], longer pectoral [21.0–22.7% (21.5%) vs. 17.0–21.0% (19.8%)] and pelvic fins [12.5–13.5% (12.8%) vs. 10.4–12.2% (11.2%)], and a greater numbers of pseudobranchial filaments [17–19 (modally 17) vs. 18–22 (19)], lateral scale rows in longitudinal series [41–43 (41) vs. 38–42 (40)] and transverse scales [11 or 12 (12) vs. 11]. There were significant differences in seven meristic and 14 morphometric characters between the two species.

Widespread Small-Scale Anisotropic Structure in the Lowermost Mantle beneath the North American Continent and Northeastern Pacific

We constrain D″ anisotropy beneath the North American continent and northeastern Pacific using two approaches: (1) joint splitting analysis of SKS and SKKS phase pair for a common event, in which we obtain 158 pairs exhibiting discrepant splitting results and 791 pairs nondiscrepant splitting results; and (2) group splitting analysis of SKS (or SKKS) phase from neighboring events recorded at a common station, in which we observe 109 2°×2° grids with consistent splitting parameters, and 164 grids with abrupt changes from splitting to no splitting within 30–100 km. The seismic data from both analyses indicate that small-scale variations of D″ anisotropy are widespread beneath the studied regions, with a lateral scale up to tens of kilometers. For portion of the data recorded at the stations of simple upper-mantle anisotropy, we correct for the effects of upper-mantle anisotropy and obtain the splitting parameters of D″ anisotropy. The inferred D″ anisotropy exhibits a changing geographic pattern and lateral transition of anisotropy to a lateral scale of tens of kilometers. Such a length scale of changing anisotropy is also confirmed by synthetics modeling of the seismic data. We suggest that the inferred small-scale anisotropies could be best explained by the shape preferred orientation of widespread small-scale partial melt pockets derived by a composition change produced early in the Earth’s history, a similar compositional origin that was invoked to explain the African anomaly in the lower mantle.

A new diurnal gecko in the genus Gonatodes (Squamata: Sphaerodactylidae) from Margarita Island, Venezuela

We describe a new species of diurnal gecko, Gonatodes machelae sp. nov., from Cerro El Copey, Margarita Island, Venezuela. The new species is distinguished from all congeners by a combination of the following characters: small size, subcaudal pattern C (1’1’’), typically three lateral scale rows on the digits, and aspects of coloration. The new species exhibits polychromatism similar to what has been described in some other species of Gonatodes. It is found in humid forests and shrublands from about 450 m to 900 m above sea level.

Влияние давления при эпитаксии на свойства слоев GaN

Growth of GaN layers by MOVPE on sapphire substrates at various pressures, including above atmospheric, was studied. It is shown that epitaxy at higher pressures does not change the crystal perfection of the layers, the electron mobility, and the impurities incorporation, but leads to the formation of a surface with a smaller lateral scale of inhomogeneities. The epitaxy pressure also affects the ratio of the intensity of the band-edge and impurity-related lines in the photoluminescence spectra and the leakage currents in the reverse-biased Schottky barrier.

Multiscale Modeling Applied to the Hydrodynamic Lubrication of Rough Surfaces for Computation Time Reduction

This paper presents a multiscale finite element method applied to the simulation of a lubricating film flowing between rough surfaces. The objective of this approach is to study flows between large rough surfaces needing very fine meshes while maintaining a reasonable computation time. For this purpose, the domain is split into a number of subdomains (bottom-scale meshes) connected by a coarse mesh (top-scale). The pressure distribution at the top-scale is used as boundary conditions for the bottom-scale problems. This pressure is adjusted to ensure global mass flow balance between the contiguous subdomains. This multiscale method allows for a significant reduction of the number of operations as well as a satisfactory accuracy of the results if the top-scale mesh is properly fitted to the roughness lateral scale. Furthermore the present method is well-suited to parallel computation, leading to much more significant computation time reduction.

A strikingly polychromatic new species of Gonatodes (Squamata: Sphaerodactylidae) from northern Venezuela

We describe a new species of diurnal gecko, Gonatodes rozei sp. nov., from tropical and premontane humid forests ofnorth central Venezuela. The new species can be distinguished from other congeners by a combination of large size, sub-caudal pattern B (1’1’1’’), three or four lateral scale rows on the digits, males with blue iris, scalation of the gular area,and aspects of color pattern in males and females. The new species is strongly sexually dichromatic and up to four different color morphs are observed in males.