The relationship between astrocytes, basal lamina and mesenchymal tissue was analyzed ultrastructurally in myelinated organotypic cultures of mouse spinal cord tissue grown in combination with its pia-arachnoid membrane. A discontinuous, well-developed basal lamina covered flat astrocytic processes which formed the basal layer of the explant opposing the pia-arachnoid membrane. Some astrocytic ...

We establish functional central limit theorems (FCLTs) for a cumulative input process to a fluid queue from the superposition of independent on-off sources, where the on periods and off periods may have heavy-tailed probability distributions. Variants of these FCLTs hold for cumulative busy time and idle time processes associated with standard queueing models. The heavy-tailed on-period and off...

The present paper addresses the nonlinear dynamical hypothesis in knowledge acquisition and problem solving. These cognitive phenomena are processes of change or imply changes, which might be trivial, smooth or discontinuous. The usual linear approaches do not capture the dynamics of these processes. This work attempts first, to build theoretical bridges between the nonlinear dynamical systems ...

We propose an approach to compute the boundary crossing probabilities for a class of diffusion processes which can be expressed as piecewise monotone (not necessarily one-to-one) functionals of a standard Brownian motion. This class includes many interesting processes in real applications, e.g., Ornstein-Uhlenbeck, growth processes and geometric Brownian motion with time dependent drift. This m...

This paper presents a theoretical approach to optimal control problems (OCPs) governed by a class of control systems with discontinuous right-hand sides. A possible application of the framework developed in this paper is constituted by the conventional sliding mode dynamic processes. The general theory of constrained OCPs is used as an analytic background for designing numerically tractable sch...

Let V denote a set of N vertices. To construct a hypergraph process, create a new hyperedge at each event time of a Poisson process; the cardinality K of this hyperedge is random, with generating function ρ(x) def = ∑ ρkx , where P (K = k) = ρk; given K = k, the k vertices appearing in the new hyperedge are selected uniformly at random from V . Assume ρ1 + ρ2 > 0. Hyperedges of cardinality 1 ar...

a review on the microstructural evolution in magnesium alloys during severe plastic deformation waspresented. the challenges deserved to achieve ultrafine/ nanostructured magnesium were discussed.the characteristics of the processed materials are influenced by three main factors, including i)difficult processing at low temperatures, ii) high temperature processing and the occurrence ofdynamic r...

studies relating form and functions of cities indicate sprawl as an intriguing research issue, especially for certain typologies of cities. although with inherent differences on a local scale, mediterranean cities offer a kaleidoscopic overview of sprawl morphologies that require dedicated monitoring tools. the present study provides an original assessment of recent urbanization processes in th...

The non-enzymatic glycation of Low density lipoprotein (LDL) is a naturally occurring chemical modification of apolipoprotein B as a result of condensation between lysine residues and glucose. Glycated LDL is poorly recognized by LDL receptors and initiates different processes that can be considered proatherogenic. Thus, LDL glycation may contribute in the increased atherosclerotic risk of pati...