HDTMA and TMPA cations intercalated bentonite clay has been assessed for the effective removal of methylene blue dye (MB) in aqueous solution. The adsorbents has been characterized by Fourier transformed infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and x-ray diffraction (XRD). Various sorption parameters like effect of initial MB concentration, contact time and pH were used to investigate the sorption process. Langmuir and Freundlich isotherms as well as Pseudo First order, Pseudo Second order and intraparticle diffusion kinetic models were applied to investigate the sorption mechanisms. Results from the adsorption experiment confirmed 180 minutes as equilibrium time for maximum sorption of MB by both organoclays. Increase in initial MB concentration resulted to a corresponding increase in the adsorption capacities of both organoclays. Adsorption of MB by the organoclays were highly influenced by pH, as maximum sorption of MB was achieved at pH of 7. Among the isotherm and kinetic models exploited, the Langmuir isotherm and Pseudo second order kinetic model gave best fit to the experimental data respectively. Results from thermodynamic studies showed that the process of adsorption of MB onto the organoclays were feasible, spontaneous and exothermic; and successful reapplication of regenerated spent organoclays (Bt-HDTMA and Bt-TMPA) yielded MB dye removal percentage of 89.6 and 85.3% respectively at 60 minutes contact time. Therefore, the results obtained from the entire study confirms the efficacy of HDTMA and TMPA intercalated bentonite clay for effective removal of cationic dyes in aqueous solution at optimal experimental conditions

Screening mammography is a vital element of breast cancer detection that has helped to reduce disease mortality [1][2][3][4]. With the current screening strategy, yearly cancer detection rate in the US is approximately five per 1000 screens and fewer than 2% of screens prove suspicious and require biopsy [5][6][7]. In an effort to improve specificity, decrease cost, and reduce harm the American College of Radiology (ACR) established the Breast ImagingReporting and Data System (BI-RADS) category 3 -probably benign designation to be used for short-term surveillance instead of immediate biopsy [8][9][10]. The morphological criteria for BI-RADS 3 include a solitary circumscribed mass with a solid ultrasound (US) correlate, focal asymmetry without an US correlate, and grouped, round calcifications [8,9,11]. Typically the designation of BI-RADS 3 is made after an initial diagnostic work-up and should not be assigned on a screening mammogram. The assignment of BI-RADS 3 activates a short-term (6-, 12-, and 24-months) follow-

Heavy metals are among the largest contaminants of food products. Once metals are present in vegetables, their concentrations are rarely modified by industrial processing techniques, although in some cases washing may decrease the metal content. In this study, levels of heavy metals in tinned, sachets, tomato pastes and fresh tomatoes sold in markets in Umuahia, Nigeria were evaluated by Atomic Absorption Spectrophotometry. The result obtained for tinned tomatoes were: iron, 0.03 -2.78 μg/g; lead, 0.01-0.18 μg/g; chromium, 0.03-0.05 μg/g; copper, 0.01-0.04 μg/g; nickel, 0.03-0.1 μg/g; zinc, 0.06 0.11 μg/g; calcium, 0.04 -0.8 μg/g and cadmium, 0.00-0.01 μg/g. The mean values for sachet tomatoes were: iron, 0.38-0.84 µg/g; lead, 0.03-0.18 µg/g; chromium, 0.03-0.04 µg/g; copper, 0.02-0.04 µg/g; nickel, 0.03-0.08 µg/g; zinc, 0.049-0.14 µg/g; calcium, 0.4-1.02 µg/g, while cadmium was not detected. The mean concentration values in fresh tomatoes sold in markets and farm land were: iron, 0.025-0.075 µg/g; lead ranges between 0.03-0.19 µg/g; chromium, 0.00-0.27 µg/g; copper, 0.002-0.10 µg/g; nickel, 0.00-0.15 µg/g; zinc, 0.05-013 µg/g; calcium, 0.24-0.74 µg/g; while cadmium was not detected in all fresh and farm land samples. These values indicate that levels of investigated metals in the analyzed tomatoes were below the permissible levels of metals recommended as dietary intake in tomato.

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The application of hexadecyl trimethyl ammonium and trimethylphenyl ammonium cation functionalized montmorillonite clay has been assessed for adsorptive removal of antimony Sb (III) in aqueous solution. Various adsorption parameters such as contact time, initial adsorbate concentration, pH and temperature have been employed to study Sb (III) adsorption behaviour onto the organoclays. Organ montmorillonite has been initially characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The Langmuir and Freundlich isotherms, as well as pseudo first order, pseudo second order and intraparticle diffusion kinetic models has been exploited in this study to investigate the equilibrium process as well as adsorption mechanism. Results from adsorption studies confirmed 18 and 20 hours as maximum contact time for equilibrium sorption for Mt-TMPA and Mt-HDTMA respectively. Langmuir and pseudo second order kinetic models gave best fit to sorption data. Thermodynamic investigation of the adoption process reveals that the process of Sb (III) adsorption onto the organoclays were feasible and endothermic. About 95.22% and 90.42% removal of Sb (III) was achieved for Mt-HDTMA and Mt-TMPA respectively by reapplication of regenerated spent organoclays for Sb (III) removal within 24 hours contact time. Result from this study substantiates the efficacy of organoclays for effective removal of antimony in aqueous medium.