Dielectric properties of oil sands at 2.45 GHz with TE1,0,11 mode determined by a rectangular cavity resonator.

Oil obtained from oil sands resources constitute an important portion of the oil industry in Canada. Extraction of the bitumen from oil sands is very crucial process because of its cost and environmental impact. Microwave energy applicators by heating oil sands at microwave frequencies can be an excellent alternative to extract bitumen with the advantages of being potentially cost-effective and environmentally friendly method of extraction. In order to design and manufacture a microwave energy applicator, its dielectric properties must be known. In this study, as the first part of our ultimate microwave energy applicator project, in advance, the complex permittivity of oil sands was measured by using rectangular cavity resonator, designed and fabricated in Ecole Polytechnique de Montréal laboratories, at 2.45 GHz with TE1,0,1 mode. The accuracy of the permittivity measurement results obtained with the developed system was verified against those obtained using a commercial open-ended probe system as well the values of well known materials documented in open literature. Since there is no study found in the literature about the complex permittivity values of oil sands at 2.45 GHz, the present study would be of great help and important guide for those who plan to design and manufacture microwave energy applicators in order to extract the bitumen from the oil sands.

T-lymphocyte activation and the levels of eosinophilic cationic protein and interleukin-5 in asthmatic children with acute exacerbation and effect of glucocorticoid treatment.

The aim of this study was to evaluate the immunologic parameters and the effects of glucocorticoid treatment, the absolute numbers of CD4+/CD25+ T lymphocytes, eosinophil counts, levels of eosinophilic cationic protein (ECP), and interleukin (IL)-5 in peripheral blood of patients having acute asthma exacerbations and healthy children were investigated. Samples for the absolute numbers CD4+/CD25+ T lymphocyte and eosinophil count, ECP, and IL-5 were obtained before (day 1) and after (day 5) glucocorticoid treatment. Forced expiratory volume in 1 second and peak expiratory flow rate were measured on days 1 and 5 in asthma patients (n = 25) and in the control group (n = 15). The absolute numbers of CD4+/CD25+ T lymphocyte and eosinophils, levels of ECP, and IL-5 were significantly greater, while forced expiratory volume in 1 second and peak expiratory flow rate were significantly less in the patients with asthma than in the control subjects on day 1. These parameters normalized after glucocorticoid treatment with clinical improvement by day 5. Glucocorticoid treatment is associated with clinical and laboratory improvement achieved in patients with acute asthma exacerbations.