By means of a thermal diffusion column the range of the radiocarbon dating method can be extended by about 20 000 years. In order to calculate suitable dimensions and operation conditions, a theory of nonlinear enrichment is derived. On the basis of a formula which describes the dependence of the enrichment factor on time and the characteristic values of the column, a concentric column of 11m l...

Introduction: Uncontrolled and improper landfilling of solid waste increases the concentration of heavy metals in the soil. Therefore, this study aimed to investigate soil contamination with heavy metals in the landfill of municipal and hospital waste in Sabzevar city by compiling a map of the severity of heavy metal pollution in the soil. Materials and Methods: Concentrations of heavy metals ...

After overnight incubation of R(+)Escherichia coli with R(-)Salmonella typhimurium in selenite and tetrathionate with Brilliant Green (TBG) broths, R-factor transfer was demonstrated in 10 of 12 experiments. R-factor transfer in these enrichment broths occurred at a markedly reduced frequency in comparison to that in Trypticase soy broth, apparently due to an adverse effect either on the viabil...

Introduction: This study aimed to assess a good protocol for the contamination indexes, concentration, spatial analysis, and source identification of toxic metals in top soils. Materials and Methods: In the first step, samples were taken from top soil (30 cm) and the metals were extracted and detected with ICP-AES. In the second step, Enrichment Factor, Geoaccumulation Index, and Contamination...

Chronic obstructive pulmonary disease (COPD) is a major global health problem. It results from chronic inflammation and causes irreversible airway damage. Levels of different serum cytokines could be surrogate biomarkers for inflammation and lung function in COPD. We aimed to determine the serum levels of different biomarkers in COPD patients, the association between cytokine levels and various...

A new metric for the evaluation of model performance in the field of virtual screening and quantitative structure-activity relationship applications is described. This metric has been termed the power metric and is defined as the fraction of the true positive rate divided by the sum of the true positive and false positive rates, for a given cutoff threshold. The performance of this metric is co...

A new metric for the evaluation of model performance in the field of virtual screening and quantitative structure– activity relationship applications is described. This metric has been termed the power metric and is defined as the fraction of the true positive rate divided by the sum of the true positive and false positive rates, for a given cutoff threshold. The performance of this metric is c...

Coastal aquatic ecosystems are environments increasingly affected by human activities due to urban discharges and their use as dumps. The objective of this study is determine the profiles metallic elements concentration (Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd, Pb) Cotonou channel sediments evaluate quality. For this, surface (0-5cm) were sampled at 13 sites along channel. Thus,Geoaccumulation I...