the assessment of the quantitative and qualitative changes, the result of the impacts imposed by natural factors, and human interventions during specific sampling periods has a substantial influence on nature, management method and tending operation of every region’s forests. the present research was carried out in golestan province forests (iran) over an 11- year period and the obtained statis...

toxicity of 38 aliphatic carboxylic acids was studied using non-linear quantitative structure-toxicityrelationship (qstr) models. the adaptive neuro-fuzzy inference system (anfis) was used to construct thenonlinear qstr models in all stages of study. two anfis models were developed based upon differentsubsets of descriptors. the first one used log ow k and lumo e as inputs and had good predicti...

genetic algorithm and partial least square (ga-pls), the kernel pls (kpls) and levenberg-marquardt artificial neural network (l-m ann) techniques were used to investigate the correlationbetween retention time (rt) and descriptors for 15 nanoparticle compounds which obtained by thecomprehensive two dimensional gas chromatography system (gc x gc). application of thedodecanethiol monolayer-protect...

predictive quantitative structure–activity relationship was performed on the novel 4-oxo-1,4-dihydroquinoline and 4-oxo-4h-pyrido[1,2-a]pyrimidine derivatives to explore relationship between the structure of synthesized compounds and their anti-hiv-1 activities. in this way, the suitable set of the molecular descriptors was calculated and the important descriptors using the variable selections ...

Recent results on the internal, measure-theoretic structure of the exponential time complexity classes E and EXP are surveyed. The measure structure of these classes is seen to interact in informative ways with bi-immunity, complexity cores, polynomial-time reductions, completeness, circuit-size complexity, Kolmogorov complexity, natural proofs, pseudoran-dom generators, the density of hard lan...

It is well known that the chemical behavior of a compound is dependent upon the structure of itsmolecules. Quantitative structure – activity relationship (QSAR) studies and quantitative structure –property relationship (QSPR) studies are active areas of chemical research that focus on the nature ofthis dependency. Topological indices are the numerical value associated with chemical constitution...