Anatomical studies of primate prefrontal cortex show strong and spatially modulated lateral excitatory connections among pyramidal neurons in the supra-granular layers. We study the role of patchy lateral excitatory connections in generating spatially localized pulses of sustained activity. When the patchy connections drive the "ring no spatially localized sustained activity is possible. When t...

Consider observation data, comprised of n observation vectors with values on a set of attributes. This gives us n points in attribute space. Having data structured as a tree, implied by having our observations embedded in an ultrametric topology, offers great advantage for proximity searching. If we have preprocessed data through such an embedding, then an observation’s nearest neighbor is foun...

Nowadays modern cars integrate advanced driving assistance systems which range up to fully automated driving modes. Since fully automated driving modes have not come into everyday practice yet, operators are currently making use of assistance systems. While still being in control of the vehicle, alerts signal possible collision dangers when, for example, parking. The reason for the necessity of...

Geometric Near-neighbor Access Tree (GNAT) is a metric space indexing method based on hierarchical hyperplane partitioning of the space. While GNAT is very efficient in proximity searching, it has a bad reputation of being a memory hog. We show that this is partially based on too coarse analysis, and that the memory requirements can be lowered while at the same time improving the search efficie...

We use household survey data from the UK to study how close ‘middle-aged’ men and women in partnerships live to their own parents and their partner’s parents. We find a slight tendency for couples to live closer to the woman’s parents than the man’s. This tendency is more pronounced among couples in which neither partner has a degree and in which there is a child. In other respects, proximity t...

This paper presents a new algorithm for real-time tracking of pairs of closest points as well as their corresponding surface features between certain general types of objects (which can be non-convex) with parametric curved surfaces. The fact that the algorithm works directly on accurate parametric descriptions of curved surfaces rather than polygonal approximation of surfaces (i.e., polygonal ...

It has been suggested that the human ability to process number and time both rely on common magnitude mechanisms, yet for time this commonality has mainly been investigated in the sub-second rather than longer time ranges. Here we examined whether number processing is associated with timing in time ranges greater than a second. Specifically,we tested longduration estimation abilities in adultsw...

Rationale Human rhinovirus (HRV) infections during early childhood are associated with a significantly increased risk of developing asthma in subsequent years [1]. There is published evidence that airway remodeling is present in pre-school children, often before the diagnosis of asthma is established [1]. It is thought that this increased risk relates to the fact that HRV infections facilitate ...

BACKGROUND It is well established that hippocampal activity is positively related to effective associative memory formation. However, in biological systems often optimal levels of activity are contrasted by both sub- and supra-optimal levels. Sub-optimal levels of hippocampal activity are commonly attributed to unsuccessful memory formation, whereas the supra-optimal levels of hippocampal activ...

In this study we assessed the effect of acute hypoxia on post-exercise parasympathetic reactivation inferred from heart rate (HR) recovery (HRR) and HR variability (HRV) indices. Ten healthy males participated in this study. Following 10 min of seated rest, participants performed 5 min of submaximal running at the speed associated with the first ventilatory threshold (Sub) followed by a 20-s al...