Chemical signaling dispersal patterns

A full understanding of chemical ecology must therefore include not only the characterization of chemically unique signals but also their environmental dispersal and degradation patterns that are an intrinsic part of chemosensory transduction and signal processing and lead to the appropriate behavioral responses. One of the most difficult tasks has been to measure the natural stimulus dispersal patterns at a spatial and temporal resolution relevant to the animal. 

The improved signal dispersion achieved due to the combined effects of H and S differentiation and the enhanced multiplet pattern simplification provided by both homo- and heteronuclear decoupling in both dimensions is also illustrated in Fig. 7. The H-15 methyl signal consists of two overlapped triplets where it is difficult to extract the exact chemical shift values in both H and conventional HSQC spectra. Note the superior performance of the SAPS approach for an automated peak picking to determine a more accurate and simultaneous determination of d( H), 5( C), AA5( H), and AAd( C) and to quantify each individual singlet signal by direct peak volume integration. 

For all those above reasons, trying to classify environmental odour sources in real life with pattern recognition techniques gives rise to a spread of observation points in the different clusters. For the signal processing, that implies to have a great number of samples in order to consider the various conditions and chemical compositions. But that induces a high dispersion of the data of a same class and/or of the same concentration. 

Since the haem methyl proton signals of MbCO were observed in the narrow chemical shift range between 2 and 4 ppm,the spreads of the haem methyl proton signals in the spectra of deoxy Mb (Fig. 10) reflected the hyperfine shift pattern of the haem methyl proton signals. Hence the larger dispersion of the haem methyl proton signals in the spectrum of Mb(7-PF) could be attributed to the significant n spin delocalisation. 

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