Degradation studies prediction tools

Stress testing is the main tool that is used to predict stability problems, develop analytical methods, and identify degradation products and pathways. Since there are no detailed regulatory guidelines that describe how to carry out stress testing studies (nor has there ever been a textbook or reference book devoted to the subject), stress testing has evolved into an artful science that is highly dependent on the experience of the company... 

Microbial biosensors have been developed based on key hydrocarbon degradation pathways. These biosensors can be used as tools to examine the regulation of the degradation pathways. In addition to the use of empirically derived data from laboratory studies, a selective meta-analysis of published data from literature sources using catabolic hydrocarbon biosensors was conducted. The aim of this work was to demonstrate that biosensor specific QSARs may be developed to first assess the specificity of degradation pathways and then to assess the possibility of predicting analyte-specific degradation characteristics. 

Chlorinated ethenes are subject to a variety of microbial degradation processes that include reductive dechlorination (Vogel et al., 1987 Maymo-Gatell et al., 1997), aerobic oxidation, anaerobic oxidation (Bradley and Chapelle, 1996), and anaerobic cometabolism (McCarty and Semprini, 1994). Both, laboratory studies (Bradley and Chapelle, 1998), and field studies (Chapelle and Bradley, 2000) show that the efficiency of chlorinated ethene biodegradation depends on ambient redox conditions. Therefore, reliable tools to measure the redox conditions are crucial to imderstand and even predict chlorinated ethene degradation. 

From a hydrogeochemical perspective, there are two major conclusions that can be drawn from this literature review. First, data protocols need to be consistent and complete with respect to redox-sensitive species in order to understand the dynamic behaviour of chlorinated ethenes in the underground and compare it between different sites. Second, the use of the steady-state approach to evaluate field data provided results, which appeared to be more meaningful than those obtained using classical redox chemical parameters. After careful calibration in several field studies, the steady-state approach may allow prediction of in-situ degradation rates and therefore turn out to be a powerful tool for the study of natural attenuation processes. 

The study of the thermal degradation of synthetic mbber nanocomposites plays an important role for different application, knowing the degradation temperature of nanocomposites is a useful tool to predict lifetimes and applications. However it is... 

Within the last decade applications of new cidture-independent molecular tools based on PCR analysis of soil-extracted nucleic acids have provided unique insights into the conqiosition, richness and structure of microbial communities (58-61). Quantitative PCR methods will be used to estimate the abundance in soils of genes that encode atrazine-degradation enzymes, and by quantifying mRNA, their expression. Magnetic capture hybridization (MCH) followed by nested PCR could predict die potential of a soil to mineralize atrazine (62). In diis study, atzA gene copy number was quantified and found to be correlated... 

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