Previous studies have shown that complex-spike cells, the most common cell type recorded in the hippocampus of freely moving rats, have the property of spatial firing--that is, a cell will fire rapidly only when the animal is in a particular part of its environment (O'Keefe and Dostrovsky, 1971). In the current study, we analyze the spatial firing of theta cells, the second major class of cells...

The spatial context of microbial interactions common in natural systems is largely absent in traditional pure culture-based microbiology. The understanding of how interdependent microbial communities assemble and coexist in limited spatial domains remains sketchy. A mechanistic model of cell-level interactions among multispecies microbial populations grown on hydrated rough surfaces facilitated...

Measurements recorded over monitoring networks often possess spatial and temporal correlation inducing redundancies in the information provided. For river water quality monitoring in particular, flow-connected sites may likely provide similar information. This paper proposes a novel approach to principal components analysis to investigate reducing dimensionality for spatiotemporal flow-connecte...

In this article, we describe two software design patterns that can be reused in the design of object-oriented geographical information systems (GIS). The first of them, called Spatial Object, captures the common structure and dynamics of the spatial entities represented in a GIS. The second one, called Spatial Graph, provides a solution to REVISTA COLOMBIANA DE COMPUTACIÓN Volumen 1, número 1 P...

drought is one of the natural disasters that causes a lot of damages each year. this phenomenon is a result of severe and repeated spatial-temporal anomalies in atmosphere circulation patterns. thus, studying and identifying the synoptic patterns of this phenomenon is inevitably necessary. in this study, first yearly rainfalls in selected stations of the uremia lake basin were temporally standa...

Local Binary Pattern (LBP) is invariant to the monotonic changes in the grey scale domain. This property enables LBP to present a texture descriptor that can be useful in applications dealing with the local illumination changes. However, the existing versions of LBP are not able to handle image illumination changes, especially in outdoor environments. These non-patterned illumination changes di...

We typically observe large-scale outcomes that arise from the interactions of many hidden, small-scale processes. Examples include age of disease onset, rates of amino acid substitutions and composition of ecological communities. The macroscopic patterns in each problem often vary around a characteristic shape that can be generated by neutral processes. A neutral generative model assumes that e...

Understanding species richness patterns represents one of the most fundamental problems in ecology. Most research in this area has focused on spatial gradients of species richness, with a smaller area of emphasis dedicated to understanding the temporal dynamics of richness. However, few attempts have been made to understand the linkages between the spatial and temporal patterns related to richn...

A central goal in ecology is to understand the spatial scaling of biodiversity. Patterns in the spatial distribution of organisms provide important clues about the underlying mechanisms that structure ecological communities and are central to setting conservation priorities. Although microorganisms comprise much of Earth's biodiversity, little is known about their biodiversity scaling relations...