THE SUMMARIZED FORMULA FOR VELOCITY OF TURBULENT AND LAMINAR FLOWS IN PIPES

On the basis of the solution of the equation of the movement (in conception of «vortex backfill”) offered earlier, the generalized formula for a profile of speed of a turbulent and laminar current in pipes is received. The formula has binomial power shape. The received solution allows to consider speed of a turbulent kernel of a stream, or, more precisely, averaged on time value of axial component of this speed, as the sum of three items - carrying, parabolic and power but not parabolic. It is shown that the profile of turbulent speed of the basic part of a stream is described by the parabolic component. Transformation of the equation of movement in which solutions both laminar, and turbulent profiles of speeds (in the basic part of a stream) are direct lines (or very close to them) is offered. Some features of turbulent flow, similar to currents in a granular layer are noted.

Timing and Laminar Profile of Eye-Position Effects on Auditory Responses in Primate Auditory Cortex

We examined effects of eye position on auditory cortical responses in macaques. Laminar current-source density (CSD) and multiunit activity (MUA) profiles were sampled with linear array multielectrodes. Eye position significantly modulated auditory-evoked CSD amplitude in 24/29 penetrations (83%), across A1 and belt regions; 4/24 cases also showed significant MUA AM. Eye-position effects occurred mainly in the supragranular laminae and lagged the co-located auditory response by, on average, 38 ms. Effects in A1 and belt regions were indistinguishable in amplitude, laminar profile, and latency. The timing and laminar profile of the eye-position effects suggest that they are not combined with auditory signals at a subcortical stage of the lemniscal auditory pathways and simply “fed-forward” into cortex. Rather, these effects may be conveyed to auditory cortex by feedback projections from parietal or frontal cortices, or alternatively, they may be conveyed by nonclassical feedforward projections through auditory koniocellular (calbindin positive) neurons.

Paleoecological succession leading to a late Ordovician biostrome on Manitoulin Island, Ontario

A 4 m thick section in the late Ordovician sequence on Manitoulin Island revealed four successively shallowing carbonate environments, each with a distinctive fossil assemblage. The lowermost quieter water, muddy level bottom community was dominated by the brachiopod Zygospira. Next, increased laminar current action attracted smaller colonies of the tabulate corals Tetradium and Columnopora, and locally small banks of corals and stromatoporoids were built up. In the protected shallow subtidal community following, encrusting algae (Girvanella) and upright match-stick Hedstroemia were more important, alongside Columnopora, cup corals, and a diverse association of thick-shelled bivalves and gastropods. The short-term paleoecological succession terminated under turbulent conditions with large colonies of Labechia, rugose coral colonies of Cyathophylloides, and tabulate corals such as Tetradium forming what is called the Wekwemikong biostrome.