Sensory exploitation

Evolution of a signaling system can also be driven by preexisting sensory biases. The signaler adapts to the receiver s sensory abilities ( sensory drive Endler and MacLellan, 1988). In acoustic communication of frogs, such an evolutionary process has been termed sensory exploitation (Ryan etal., 1990). 

Ryan, M. J. (1990). Sexual selection, sensory systems and sensory exploitation. Oxford Surveys in Evolutionary Biology 7 156-195. 

There is an increasing interest in the development of electrochemical sensors and microsensors for detecting and monitoring NO or N02, due to their importance in clinical and environmental analysis. It has been suggested that transition metal electrocatalysts active for NO or N02 coordination and reduction could be exploited for the development of metal-complex film electrodes for N02 and NO sensing. However, most of the sensory devices reported so... 

Several analytical devices have found application as test sensors or, more generally, as electronic tongues for characterizing foods or food ingredients, being able to provide information related to the human sensorial perception or to other important features. There are some examples of electronic tongues based on optical techniques as well as on mass measurements, but the analytical methods that have been most widely exploited in this field are, without any doubt, the electrochemical ones, as shown in Fig. 2.6. 

Bisulfite addition products are readily formed at wine pHs (1, 23, 24). The bisulfite addition product is thought to be a more sensory-neutral compound and may be exploited by winemakers as a means of decreasing the aldehydic character of wines (1). Bisulfite addition has also been used to mask the stale flavor of beer which is thought to be largely due to the formation of trans-l-noneml (25). Kaneda et al. (25) used HPLC with fluorescent detection of an o-phthalaldehyde derivative to quantitate and identify individual aldehyde-bisulfite products, however, only acetaldehyde-bisulfite adducts were observed in commercial beers with this method. Hydrolysis of the adducts occurs at pHs greater than 8, therefore by adjusting the pH prior to analysis, total aldehydes (free plus bisulfite bound) can be estimated. At low pHs accurate estimation of free aldehydes is complicated however, by analysis conditions which alter the equilibrium between bound and free forms (temperature, dilution, solvent extraction, analysis time, etc.). 

In the world of fruits many other sensorially interesting fruits exist. Most of them are known only locally, and they are unknown to the consumers in the large markets. Especially many tropical fruits have never been exploited for their commercial value and they run the risk to disappear from the biosphere. Some have found an interest in home made products ... 

One remaining problem with tissue-specific null mutants that exploit the Cre/ lox-P system is that early excision at the time of birth of sensory neurons may allow developmental compensatory mechanisms to occur, again complicating phenotypic analysis, particularly in terms of behaviour. It would thus be ideal to be able to delete genes in adult animals, whose behaviour under control conditions has already been assessed. Recent advances in gene dehvery suggest that this approach may be feasible. 

In a step towards the fabrication of prototype sensory devices organisation of redox-active anion receptors on to electrode surfaces is being exploited. Importantly, self-assembled monolayers or thin polymer films of metal-based receptors can generate an amplified response to anion binding akin to the dendritic effect and could potentially become the basis of robust anionsensing devices. 

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