RESUMO
Radioactive europium can be released as a fission product during nuclear incidents and pose a threat to the human and surrounding environment because of its biological activity and long decay half-lives. For safe design issues and human health protection demands in construction of the planned nuclear power plants (NPPs) at Al-Dabaa site, it is necessary to study the sorption and transport of different radionuclides as europium within the selected area for predicting their fate at any crisis. Many soil samples were collected from different locations at the area selected along the northwestern coast of Egypt. The samples were transported to the laboratory, preserved, and characterized using X-Ray fluorescence (XRF), Fourier transform infrared spectroscopy (FT-IR), and X-Ray diffraction (XRD). Experiments were performed to study the sorption and transport kinetics of Eu(III) ions on two sandy soil samples from the collected ones. The effect of different parameters (e.g. contact time, pH, initial europium concentration, and temperature) on the sorption behavior europium was explored in a static condition. The maximum sorption capacity was determined and found to be 3.4 and 7.0 mg g-1 for sorption of Eu(III) ions onto soil-1 and soil-2, respectively. Different models were applied to assess the sorption of europium onto the surface of the investigated soils. Data confirmed that Eu retention was attained through a chemisorption process. Further, the thermodynamic parameters were determined and their values confirmed the endothermic nature of the sorption process. The transport of europium radionuclides, with groundwater, through homogeneous porous media with uniform one-dimensional flow in the geosphere was processed and the relative migration velocity was determined in presence of both distilled and seawater media. The transport of Eu(III) radionuclides was higher in presence of seawater than that in presence of distilled water by about two order of magnitude. This obviously clarified the effect of seawater in accelerating the transport of radionuclides with groundwater in the geosphere of studied area. The role of different competing ions have various valances on the relative migration velocity was explored. Further, the time required for studied radionuclides to reach Mediterranean Sea was determined.
RESUMO
BACKGROUND: Sleeve gastrectomy (SG) and one-anastomosis gastric bypass (OAGB) are among the commonly performed bariatric procedures. This randomized study aimed to compare SG and OAGB in terms of weight loss, improvement in comorbidities, and change in serum ghrelin and glucagon-like peptide-1 (GLP-1) levels. PATIENTS AND METHODS: This was a prospective randomized trial on patients with morbid obesity associated with medical comorbidities who were randomly assigned to 1 of 2 equal groups; group I underwent SG and group II underwent OAGB. Outcome measures were percent of excess weight loss (%EWL), improvement in comorbidities, change in the venous levels of fasting ghrelin and postprandial GLP-1 at 12 months after surgery, in addition to operation time and complications. RESULTS: Forty patients (38 female) of a mean age of 33.8 years and mean body mass index of 48.6 kg/m2 were included. Operation time in group II was significantly longer than in group I (86 vs. 52.87 min; P<0.001). There were 6 recorded complications (1 in group I and 5 in group II, P=0.18). The %EWL, %total weight loss, and %excess body mass index loss at 6 and 12 months postoperatively were significantly higher in group II than in group I. Both groups had similar rates of improvement in comorbidities. Group I had significantly lower ghrelin and GLP-1 levels postoperatively at 6 and 12 months, respectively, as compared with group II. CONCLUSIONS: OAGB was associated with significantly higher EWL than SG. The reduction in fasting ghrelin and postprandial GLP-1 serum levels at 12 months after SG was significantly higher than that after OAGB.
