-The use of earthworms to bioremediate soil results in decreasing the pollutant concentration through a bioaccumulation mechanism of the contaminants in the earthworm's body. The present work is an empirical study that was carried out on soils contaminated with chromium and cadmium. Organic matter in the amount of 5% and 9% of soil weight was added. Chromium and cadmium concentrations in soil and in the body of worms were measured at two time periods of 21 and 42 days. According to the results, increasing from 5% to 9% the organic material of the soil contaminated with chromium at the initial concentration of 0.06 mg/g, the removal efficiency decreased by 5%. In 0.1 mg/g concentration the bioremediation efficiency decreased by 20%, showing that the earthworms probably have more tendency to consume the organic material and low tendency for consuming the soil contaminated by metal. Results showed that, considering the increased mortality of worms in the soil at a concentration of 0.08 mg/g of chromium, using this method is not recommended. For cadmium we require more study, though we can say that the organic material had no influence on the bioremediation of the soil.

A B S T R A C TApplication of various biomaterials to toxic compounds and heavy metals removal from aqueous solutions and industrial wastewaters is an efficient and low-cost method, in this regard macro and microalgae have revealed high potential for the biosorption of such metals. In this work, removal of Cr(VI) from synthetic aqueous solutions by powdered filamentous green algae Spirogyra porticalis was studied as an effect of various parameters including pH, biomass dosage, initial Cr(VI) concentration, and contact time in batch experiments. In order to do the statistical analysis, repeated measure test using SPSS 16.0 software was applied and p-value < 0.05 was considered as significant level. The results showed that the removal of Cr(VI) increased with the increase in the algal dosage, metal concentration, contact time, and decreasing pH. The optimum pH, biomass dose, initial concentration of Cr(VI), and contact time were found to be 3.0, 1 g/L, 40 mg/L, and 60 min, respectively. Under these conditions, the removal percentage of chromium(VI) and the specific removal capacity were found to be 70% and 27.48 mg/g, respectively. The findings of the present study indicated that S. porticalis can be used as an available, affordable, and efficient biosorbent to Cr(VI) removal from aqueous solutions and industrial acidic wastewaters containing high concentrations of chromium.

Introduction and purpose: Hospitalizations can affect the sleep quality in the elderly. A variety of factors contribute in sleep quality changes. The aim of this study was to evaluate sleep quality and its associated factors in hospitalized elderly patients in hospital.