Monitoring diversity

Ideally, any diversity-based design using a similarity radius-based concept should result in a diverse, but representative child library. Not too few compounds should be selected to maintain information from the entire virtual library. Database self-similarity and comparison plots are useful tools in this context for analysis to monitor diversity, repre-sentivity and complementarity to a corporate collection, as shown schematically in Figure 13.11. 

A variety of ludferase-based reporters for monitoring diverse cell biological processes are commercially available. For example, ludferase-based reporters of other pathways such as the BMP and Notch pathways can be used for similar multiplexed lucifer-ase screening projects. 

Chromatographic techniques, particularly gas phase chromatography, are used throughout all areas of the petroleum industry research centers, quality control laboratories and refining units. The applications covered are very diverse and include gas composition, search and analysis of contaminants, monitoring production units, feed and product analysis. We will show but a few examples in this section to give the reader an idea of the potential, and limits, of chromatographic techniques. 

Laborelec is the Belgian laboratory for the electricity industry. It deals with measuring and studying problems arising with the production, transport and distribution of electricity to industrial and private customers. It has developed very diverse domains of expertise, such as acoustics, material characteristics, technical audits to telecommunications, vibrations monitoring, etc... 

The applications of this simple measure of surface adsorbate coverage have been quite widespread and diverse. It has been possible, for example, to measure adsorption isothemis in many systems. From these measurements, one may obtain important infomiation such as the adsorption free energy, A G° = -RTln(K ) [21]. One can also monitor tire kinetics of adsorption and desorption to obtain rates. In conjunction with temperature-dependent data, one may frirther infer activation energies and pre-exponential factors [73, 74]. Knowledge of such kinetic parameters is useful for teclmological applications, such as semiconductor growth and synthesis of chemical compounds [75]. Second-order nonlinear optics may also play a role in the investigation of physical kinetics, such as the rates and mechanisms of transport processes across interfaces [76]. 

In addition, under the Nonproliferation Treaty, which most larger nations have signed, the IAEA monitors plutonium from power reactors so as to detect covert diversion. 

In 1974, the Harmonized Monitoring Programme was set up by the Department of the Environment (DoE). The objective was to provide a network of sites at the lower end of catchments, where water quality data could be collected and analysed in a nationally consistent manner, allowing the loads of materials carried through river catchments into estuaries to be estimated and long-term trends in river quality to be assessed. The complete list of substances to be monitored is diverse and specifies about 115 substances. The pesticides aldrin, dieldrin, y-HCH, heptachlor, p,p -DDT and p,p -DDE are included. Figures 1 and 2 show the downward trend of y-HCH and dieldrin over the past 20 years at the Harmonized Monitoring Sites. This confirms that reductions in environmental concentrations have been achieved, particularly over the past 10 years. 

In summaiy, periphyton are present in all lakes, easy to sample, and would respond rapidly to changes in the abundance of MeHg. Periphyton are sometimes eaten directly by fish. The diverse, complex, and variable nature of the periphyton community, however, would complicate interpretation of mercury concentrations in periphyton in a monitoring program. 

Elkan and Horvath170 performed a microbiological analysis of samples taken from the north and south deep monitoring wells in December 1974, about 6 months after the dilute waste front had reached the south well. Both denitrifying and methanogenic bacteria were observed. The lower numbers and species diversity of organisms observed in the south monitoring well compared with those in the north well indicated suppression of microbial activity by the dilute wastes. 

With adequate resources and effort, the tools are available to chemically identify many more semiochemicals in Hymenoptera. Much is still to be understood about the chemically-mediated communication in this large and diverse insect order. In addition,because many hymenoptera are significant beneficial or pest insects, and the use of semiochemicals in the management and monitoring of insects is becoming standard, the identification of additional semiochemicals in Hymenoptera is an economically worthwhile endeavor. 

Proteases are one of the largest families of enzymes and are involved in a multitude of vital processes. Due to their biological relevance and diversity, multiple fluorescent reporters monitoring their activity have been designed and successfully applied in vitro and in vivo [112-114]. Standard small molecule FRET probes for proteases consist of an amino acid sequence flanked by a FRET pair, consisting of two fluorophores or one fluorophore and a quencher molecule. Upon cleavage of the peptide sequence, the emission of the donor fluorophore is dequenched and the intensity increases whereas the emission of the acceptor decreases and vanishes more or less completely in those cases where the acceptor is fluorescent (see Fig. 6.11). 

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