Track topics on Twitter Track topics that are important to you
In this study, the depuration half-lives of 62 polychlorinated biphenyl (PCB) congeners in juvenile rainbow trout (Oncorhynchus mykiss) were estimated from their structural features based on QSPR methodology. A genetic algorithm (GA) was applied as a variable subset selection strategy and QSPR models established upon multiple linear regression (MLR), multilayer perceptron neural network (MLP NN) and support vector regression (SVR) procedures. Robustness and predictive stability of the constructed models were evaluated through internal and external validation methods. The high numerical values of [Formula: see text] and [Formula: see text], and low RMSE in the case of the MLP NN model, confirm the supremacy of this model as well as nonlinear dependency of molecular structural features to the PCB congeners half-lives. In the best developed QSPR model the following four descriptors are used; lopping centric index (Lop), mean topological charge index of order 1 (JGI1), Geary autocorrelation lag-8/weighted by atomic Sanderson electronegativities (GATS8e) and highest eigenvalue of Burden matrix/weighted by atomic masses (BEHm3). Analysis of the descriptors involved in these models revealed that 2D molecular structural features, compactness and electronegativities are the main factors contributing to the half-lives of PCBs. The structural information presented in this work can be used for further evaluation of half-lives of PCBs and other similar structural compounds in the environment.
a Chemometrics Laboratory, Faculty of Chemistry , University of Mazandaran , Babolsar , Iran.
This article was published in the following journal.
Name: SAR and QSAR in environmental research
Polychlorinated dibenzo-p-dioxins (PCDDs) are of global concern due to their persistence, bioaccumulation and toxicity. Although the fate of PCDDs in the environment is determined by their physical-ch...
Polychlorinated biphenyls (PCBs) produced in Slovakia as a commercial mixture Delor 103 cause the main contamination of sediment, water and fish in the eastern part of Slovakia. Delor 103 is a mixture...
Biomagnification of organic pollutants in food webs has been usually associated to hydrophobicity and other molecular descriptors. However, direct information on atoms and substituent positions in a m...
The present study evaluates for the first time the determination of 20 hydroxylated polychlorinated biphenyl (OH-PCB) congeners and their glucuronide and sulfate conjugates in urine as a biomarker of ...
Past studies have shown potentially increasing levels of polychlorinated biphenyls (PCBs) in the Indian environment. This is the first attempt to investigate the occurrence of PCBs in surface soil and...
The purpose of this prospective single center study is to investigate if the accuracy of length based body weight estimation by the already investigated algorithm (CLAWAR) can be improved ...
Estimation of Glomerular Filtration Rate (GFR) is the primary test used to assess patients with renal disease. Although serum creatinine based GFR and nuclear medicine based estimations ar...
Parenteral nutrition-associated cholestasis (PNAC) is one of the most common complications resulting from administration of parenteral nutrition in neonates. Excess intravenous intake of v...
Coronary heart disease (CHD) is the leading cause of death in the United States, but fewer than half of all individuals at risk for CHD take advantage of proven strategies to lower their c...
Periodontitis and Rhematoid arthritis are chronic inflammatory diseases which share common risk factors The purpose of this study is to determine if Pentraxin 3 and Porphyromonas Gingival...
Industrial products consisting of a mixture of chlorinated biphenyl congeners and isomers. These compounds are highly lipophilic and tend to accumulate in fat stores of animals. Many of these compounds are considered toxic and potential environmental pollutants.
Techniques used to determine the age of materials, based on the content and half-lives of the RADIOACTIVE ISOTOPES they contain.
Steroidal compounds related to TESTOSTERONE, the major mammalian male sex hormone. Testosterone congeners include important testosterone precursors in the biosynthetic pathways, metabolites, derivatives, and synthetic steroids with androgenic activities.
Steroidal compounds related to ESTRADIOL, the major mammalian female sex hormone. Estradiol congeners include important estradiol precursors in the biosynthetic pathways, metabolites, derivatives, and synthetic steroids with estrogenic activities.
Steroidal compounds related to PROGESTERONE, the major mammalian progestational hormone. Progesterone congeners include important progesterone precursors in the biosynthetic pathways, metabolites, derivatives, and synthetic steroids with progestational activities.