Sensors olfactory

When one looks at studies on how the dog s nose moves the dust particles [1] to the smell sensors with his nose hairs and mucus, then one realizes that the water in the mucus dissolves the TNT off the dust and offers it to the olfactory sensors. Fjellanger also quoted literature of how a dog s nose uses side muscles to pulse air at a frequency of 3 to 5 puffs per second at the slits on the side of his nostrils when sniffing. The dog then sucks the stirred up dust with a long... 

The aforementioned theories arc concerned wilh Ihc size and shape of odorant molecules, but differ in certain underlying concepts. For example, accommodating for functional groups, electron donor-acceptor characteristics, as well as Ihc sorptive nature of odorants on sensor sites. The vibration Iheory largely concentrates on the far-infrared and Raman spectral characteristics of odoriferous substances. The remaining theories concentrate on structural and behavior characteristics of odorant molecules, stressing direct interactions physically, chemically, and biologically wilh the olfactory sensor system. 

Martinelli, E., D Amico, A., Di Natale, C. Spike encoding of artificial olfactory sensor signals. 

Herbivores can typically sense suitable host plants using olfactory cues from long distance. Many volatile terpenoids bear the essential information in their molecular structure. Different stereo isomers of the same compound may result in different response when sensed by insect antennae or the olfactory sensors in the nose of vertebrate animals. Another important factor affecting signal perception and behavioral response in herbivore is the relative proportion of different volatile compounds, terpenoids or other volatiles, in the odor plume released by a plant. CombinatiOTi of certain monoterpenes and sesquiterpenes are very distinctive in certain plant families. Specialist herbivore species can separate these combinations from similar monoterpenes released by other plants, because of their strict ratio in the host species. 

The sensor response depends not only on the polarity of the analyte, but also on the flow environment. In the mammalian olfactory system, the nasal cavity structure plays an extremely important role in odor discrimination13. 

Identical olfactory neurons are located in different places in the cavity, and therefore occupy different positions in the flow path. By using a nasal cavity model, we investigated the influence of the dynamic flow on the sensors response14. The responses from identical fiber optic sensors located... 

The results demonstrate (i) that in turbulent odor plumes, purely chemical spatial gradients can be calculated when measuring with sensors scaled to lobster olfactory organs, (ii) that rapid odor access to the lobster s olfactory organs (under low ambient flow conditions) is accom-... 

These systems are formed by a number of cooperating individual non-selective sensors, whose outputs are processed to form chemical images or, in the presence of odors, olfactory images. 

I. Lundstrom, R. Erlandsson, U. Frykman, E. Hedborg, A. Spetz, H. Sundgren, S. Welin and F. Winquist, Artificial olfactory images from a chemical sensor using a light-pulse technique, Nature, 352(6330) (1991) 47-50. 

I. Lundstrom, C. Svensson, A. Spetz, H. Sundgren and F. Winquist, From hydrogen sensors to olfactory images—twenty years with catalytic field-effect devices, Sens. Actuators B Chem., 13(1-3) (1993) 16-23. 

Insects are the most diverse group animals on earth, with approximately five million species described to date (Novotny et al. 2002). Amidst this great diversity are adaptations common to all insects that maximize inclusive fitness in their respective habitats. One such fundamental adaptation is the ability to respond to cues in the environment, in particular the ability to detect external biological compounds via a chemical sensor. The sophisticated olfactory system of insects is able to sense volatile odorants derived from prey, host plants, and conspecific individuals. These compounds are detected by olfactory receptor neurons (ORNs) housed in the antennae, and these ORNs relay information about food sources, oviposition sites, and mates that leads to behavior based on neural responses mediated by the ORNs. The binding... 

Nature has devised some of the most refined and effective chemical sensors that are in existence. The olfactory system is an excellent example of what nature can do. Much work has been done in the field of sensors to create an artificial nose that can detect and differentiate virtually unlimited varieties of chemical mixtures at extremely low concentrations (often at parts per trillion levels Di Natale 1998). 

Winquist, R, Wide, P, Eklov, T., Hjort, C., and Lundstrom, I. Crispbread quality evaluation based on fusion of information from the sensor analogies to human olfactory, auditory and tactile senses, /. Food Process Eng., 22, 337, 1999. 

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