Economic targets attacks

Purine and pyrimidine nucleotides are essential components of many biochemical molecules, from DNA and RNA to ATP and NAD. In recent years, the pyrimidine and especially the purine metabolism of parasitic helminths have been investigated extensively, mainly because they are different from the pathways in the mammalian host such that they have potential as targets for chemotherapeutic attack. For a review of purine and pyrimidine pathways in parasitic helminths and protozoa, see Berens et al. (1995). Although parasitic helminths do not synthesize purines de novo, but obtain them from the host, they do possess elaborate purine salvage pathways for a more economical management of this resource. Pyrimidines, on the other hand, are synthesized de novo by all parasitic flat-worms studied so far and, as with mammalian... 

Cl systems can be the target of malicious attacks or fail due to accidental faults, generating effects that can cause unacceptable losses. That loss can be a catastrophic consequence (physical harm, property damage, etc.—i.e., safety concerns), an impairment of civil/personal rights (e.g., privacy infringement), an economic detriment, or the triggering of social and political unrest. This broad set of cases shows how problematical it can be to assess CIs and to define effective protection instruments. 

Matsumoto and Mochida [33], using NMR with a hydrogenated coal tar pitch mesophase carbon fiber, showed that the initial attack by oxygen was on -CH3 and -CH2- groups, with the gradual formation of carboxyls, esters and aryl carbonyls. Fairly stable cross-links were formed via phenols, ethers and esters. The workers also found that slower heating rates (0.5°C/min instead of 2.0°C/min) produced better mechanical properties and that the final choice would be controlled by the desired target properties and economics. 

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