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A monopole antenna operated at 2.45 GHz and embedded with artificial magnetic conductor (AMC) for wearable communication systems is investigated in this article. The proposed antenna is composed of a metalized loop radiator with a coplanar waveguide microstrip feedline which is affixed on a cotton fabric material substrate. As well, a cotton-based AMC surface is utilized to eliminate the body’s absorbed radiation and enhance the gain of the antenna. It is composed of 5 × 5 array unit cells etched with I-shaped slots. Using this configuration, simulations show that the specific absorption rate (SAR) level was significantly reduced. Considering flat and rounded body parts, it was found that the SAR values averaged over 10 g at a distance of 1 mm away from the tissues model were only 0.18 W/kg and 0.371 W/kg, respectively. Additionally, the antenna gain was improved up to 7.2 dBi with an average radiation efficiency of 72%. Detailed analysis with experimental measurements of the cotton-based antenna for different operation scenarios is introduced. The measured data show a good correlation with the electromagnetic simulation results. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to prepare folic acid coated tin oxide nanoparticles (FA-SnO2 NPs) for specifically targeting human ovarian cancer cells with minimum side effects against normal cells. Methods: The prepared FA-SnO2 NPs were characterized by FT-IR, UV-vis spectroscopy, XRD, SEM and TEM. The inhibition effects of FA-SnO2 NPs against SKOV3 cancer cell were tested by MTT and LDH assay. Apoptosis induction in FA-SnO2 NPs treated SKOV3 cells were investigated using Annexin V/PI, AO/EB and Comet assays and the possible mechanisms of the cytotoxic action were studied by Flow cytometry, qRT-PCR, Immunohistochemistry, and Western blotting analyses. The effects of FA-SnO2 NPs on reactive oxygen species generation in SKOV3 cells were also examined. Additionally, the safety of utilization FA-SnO2 NPs were studied in vivo using Wister rats. Results: The obtained FA-SnO2 NPs displayed amorphous spherical morphology with an average diameter of 157 nm and a zeta potential value of -24 mV. Comparing to uncoated SnO2 NPs, FA-SnO2 NPs had a superior inhibition effect towards SKOV3 cell growth that was suggested to be mediated through higher reactive oxygen species generation. It was showed that FA-SnO2 NPs increased significantly the % of apoptotic cells in the sub- G1 and G2/M phases with a higher intensity comet nucleus in SKOV3 treated cells. Furthermore, FA-SnO2 NPs was significantly increased the expression levels of P53, Bax, and cleaved Caspase-3 and accompanied with a significant decrease of Bcl-2 in the treated SKOV3 cells. Conclusion: Overall, the results suggested that an increase in cellular FA-SnO2 NPs internalization resulted in a significant induced cytotoxicity in SKOV3 cancer cells in dose-dependent mode through ROS-mediated cell apoptosis that may have occurred through mitochondrial pathway. Additionally, the results confirmed the safety of utilization FA-SnO2 NPs against living systems. So, FA-SnO2 NPs with a specific targeting moiety may be a promising therapeutic candidate for human ovarian cancer. [ABSTRACT FROM AUTHOR]