Human fingerprint

A fingerprint ofa chemical structure tries to identify a molecule with some special characteristics, much in the same way as a human fingerprint identifies a person. The characteristic property can, for example, be described by the structure or struc-... 

Leeches respond to chemical cues from potential hosts. Even a human fingerprint on the inner wall of a glass container triggers searching movements in a leech. 

The major constituents of biomass are present at low levels in DOM. The median freshwater contains 1.3p,molL of total hydrolyzable amino acids, the most abundant of which are glycine (20%), aspartic acid (12%), alanine (10%), glutamic acid (9%), and serine (9%). Collectively, the amino acids account for 1.8% of the organic carbon in DOM and —18% of its nitrogen. Free amino acids also exist in freshwaters, but the median concentration of 0.3 p,mol is a factor of 4-5 lower than the concentration of bound amino acids. Elevated levels of serine and ornithine in the data set for free amino acids strongly suggest that some samples may have been contaminated by human fingerprints. 

Chemistry is often iike detective work. To figure out the submicroscopic structure of a compound, you first have to examine some of its macroscopic properties. Just as no two human fingerprints are the same, no two substances have exactiy the same combination of physicai and... 

Figure 13.20 HPLC of amino acid derivatives detected by 254 nm UV absorption (a) 200 pmol of PTC-amino acid standard, including pbospboserine (PH-S), pbospbothreonine (PH-T), bydroxy-proline (OH-P), galactosamine (Gal), norleucine (NLE, 1 nmol internal standard), excess reagent (Re), and other amino acids designated by one letter codes listed in Fig. 13.19 and (b) Analysis of a human fingerprint, taken up from a watchglass using a mixture of water and ethanol. (Courtesy of National Gallery of Art and the Andrew W. Mellon Foundation.) (Cazes, used with permission.)...

The same patterns, stripes and hexagons, appear in completely different physical systems and on different spatial scales. For instance, stripe patterns are observed in human fingerprints, on zebra s skin and in the visual cortex... 

Scientists recognized that an element s spectrum is like human fingerprints just as each person has unique fingerprints, each element in the periodic table has a unique spectrum. The spectrum of a compound is simply a combination of the spectra of the elements in that compound. The uniqueness of spectra makes them powerful analytical tools in the identification of the elements found in minerals, in biological samples, in Earth s atmosphere, and in the atmospheres of stars. Although much... 

The fact that mass, infra-red, NMR and ultra-violet spectra and, to a certain extent, also chromatographic retention data can be considered as molecular fingerprints , forms the basis of most computerised library search systems. Retrieval methods for characteristic chemical data and techniques for the comparison of human fingerprints have similar elements the first step is to clean up the raw data, then in many cases a data reduction is carried out by selection of prominent features. Finally, there is the comparison of unknown and reference data patterns, which, for a useful result, requires a statistical correlation to be established. In this paper no attention will be paid to feature selection. 

Cortes-Salazar, R, Zhang, M., Becue, A., Busnel, J.-M., Prudent, M., Champod, C., Girault, H. H. Human fingerprint imaging by scanning electrochemical microscopy (SECM). Chimia 2009, 63, 580. 

FIGURE 18.4 (a) SECM feedback image of a human fingerprint developed by benzoquinone tagging with... 

His grandson, William James Herschel, reaUzed that human fingerprints are unique and was the first person to understand their utiUty. (J. E. Purlqme noted their uniqueness in 1823 but did not understand their usefulness. ... 

---