Combinatorial receptor codes for odors.

Combinatorial Receptor Codes for Odors

The discriminatory capacity of the mammalian olfactory system is such that thousands of volatile chemicals are perceived as having distinct odors. Here we used a combination of calcium imaging and single-cell RT-PCR to identify odorant receptors (ORs) for odorants with related structures but varied odors. We found that one OR recognizes multiple odorants and that one odorant is recognized by mu...

Temporally diverse firing patterns in olfactory receptor neurons underlie spatiotemporal neural codes for odors.

Odorants are represented as spatiotemporal patterns of spikes in neurons of the antennal lobe (AL; insects) and olfactory bulb (OB; vertebrates). These response patterns have been thought to arise primarily from interactions within the AL/OB, an idea supported, in part, by the assumption that olfactory receptor neurons (ORNs) respond to odorants with simple firing patterns. However, activating ...

Combinatorial batch codes

In this paper, we study batch codes, which were introduced by Ishai, Kushilevitz, Ostrovsky and Sahai in [4]. A batch code specifies a method to distribute a database of n items among m devices (servers) in such a way that any k items can be retrieved by reading at most t items from each of the servers. It is of interest to devise batch codes that minimize the total storage, denoted by N , over...

Combinatorial Codes 94

Combinatorial Constructions for Optical Orthogonal Codes

A (v, k, λ) optical orthogonal code C is a family of (0, 1) sequences of length v and weight k satisfying the following correlation properties: (1) ∑ 0≤t≤v−1xtxt+i ≤ λ for any x = (x0, x1, . . . , xv−1) ∈ C and any integer i ̸≡ 0 (mod v); (2) ∑ 0≤t≤v−1xtyt+i ≤ λ for any x = (x0, x1, . . . , xv−1) ∈ C, y = (y0, y1, . . . , yv−1) ∈ C with x ̸= y, and any integer i, where the subscripts are taken mo...