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The increased demand for computed tomography (CT) in radiological scanning examinations raises the question of a potential health impact from the associated radiation exposures. Focusing on CT kidney-ureter-bladder (CT-KUB) procedures, this work was aimed at determining organ equivalent dose using a commercial CT dose calculator and providing an estimate of cancer risks. The study, which included 64 patients (32 males and 32 females, mean age 55.5 years and age range 30-80 years), involved use of a calibrated CT scanner (Siemens-Somatom Emotion 16-slice). The CT exposures parameter including tube potential, pitch factor, tube current, volume CT dose index (CTDI vol ) and dose-length product (DLP) were recorded and analyzed using CT-EXPO (Version 2.3.1, Germany). Patient organ doses, including for stomach, liver, colon, bladder, red bone marrow, prostate and ovaries were calculated and converted into cancer risks using age-and sex-specific data published in the Biological Effects of Ionizing Radiation (BEIR) VII report. With a median value scan range of 36.1 cm, the CTDI vol , DLP, and effective dose were found to be 10.7 mGy, 390.3 mGy cm and 6.2 mSv, respectively. The mean cancer risks for males and females were estimated to be respectively 25 and 46 out of 100,000 procedures with effective doses between 4.2 mSv and 10.1 mSv. Given the increased cancer risks from current CT-KUB procedures compared to conventional examinations, we propose that the low dose protocols for unenhanced CT procedures be taken into consideration before establishing imaging protocols for CT-KUB.

In this paper, the adsorption performance of packed bed column with amine functionalized radiation-induced grafted fibers (AFF) for the removal of acid blue 80 (AB 80) was investigated. Pretreated banana fibers were grafted with glycidyl methacrylate (GMA) with the assistance of electron beam irradiation and subsequently functionalized with imidazole, which was used as the precursor of anionic dye adsorption. The effect of flow rate, bed height and inlet concentration on the breakthrough curves were analyzed in terms of AFF adsorption performance. The experiment revealed that the increase in bed height and inlet concentration promoted the adsorption efficacy, whereas reduction was observed when the flow rate increased. The highest bed capacity obtained was 194.45 mg/g at adsorption condition of 5 ml/min flow rate, 100 mg/l inlet concentration and 50 mm of bed height. In order to determine the optimum operational parameters, the data were collected via the experiment fitted into Yoon and Nelson, and Thomas and Bed Depth Service Time (BDST) mathematical models. At various conditions, Thomas model closely defined the behaviors of the breakthrough curves. The maximum adsorption capacity calculated from Yoon-Nelson and Thomas models increased with the increase in flow rate and inlet concentration. However, a reduction was observed with the increase in bed height. Meanwhile, the BDST model exhibited good agreement with the experimental data as well as high correlation coefficient value r 2 ~ 0.99, which indicated the validity of BSDT model for the column adsorption system with AFF. The experimental results attained had suggested that developed AFF is quite effective as a biosorbent for the removal of the dyes.

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