Out of darkness

Out of darkness.

Out of darkness: long non-coding RNAs come of age

It has been known for a number of years that only about 2% of this RNA encodes proteins. However, numerous studies employing both tiling arrays and high-throughput sequencing found that the genome is pervasively transcribed, with most DNA copied, at least at some point in time, into RNA. Indeed, Birney et al. (2007) estimated that 93% of the human genome is transcribed. Because of a dearth of f...

Cutaneous lupus vulgaris: Bringing the wolf out of the darkness

Lupus vulgaris is the commonest form of cutaneous tuberculosis accounting for about 75% of the cases. Clinical dermatologists need to be aware of the myriad clinical presentations of this condition as it can be misdiagnosed especially when the index of suspicion is low. It is important to make a diagnosis and promptly treat as it can be disfiguring and destructive. Introduction Tuberculosis (TB...

Darkness filling-in: a neural model of darkness induction

A model of darkness induction based on a neural filling-in mechanism is proposed. The model borrows principles from both Land's Retinex theory and BCS/FCS filling-in model of Grossberg and colleagues. The main novel assumption of the induction model is that darkness filling-in signals, which originate at luminance borders, are partially blocked when they try to cross other borders. The percenta...

Topology of light's darkness.

We numerically study the topology of optical vortex lines (nodal lines) in volumes of optical speckle, modeled as superpositions of random plane waves. It is known that the vortex lines may be infinitely long, or form closed loops. Loops are occasionally threaded by infinite lines, or linked with other loops. We find the probability of a loop not being threaded decays exponentially with the len...