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The contamination of Enterococcus bacterium is widely observed in the living environment and water. The decontamination of drinking water from the bacterial pollution is an important issue in water treatment. Here, the inactivation of Enterococcus bacteria is studied by placing the dielectric barrier discharge structure, with the RF discharge frequency of 13.56 MHz atmospheric pressure argon plasma jet, directly in water, whereas the water around the plasma plume was seething and the bubbles produced stirring all liquid volume. The ability to place a plasma jet nozzle directly in water for 10 min while maintaining a steady and uniform plasma plume, besides water temperature, provides the effectiveness enhancement in the inactivation of bacteria. The absorption of UV radiation in water is effective, and the role of UV radiation of plasma plume was mainly responsible for the destruction of peptidoglycan, which is the outer layer of Enterococcus. Then, the presence of electrons and plasma plume in water leads to the formation of hydroxyl, hydrogen peroxide, and other reactive radicals that are involved in chemical reactions, which lead to the inactivation of micro-organisms. The number of bacteria decreases from the initial value of 16 × 105 MPN/100 ml to less than 1.2 MPN/100 ml. The spectra of the plasma radiation, with the plume length 2 cm within the water, have been analyzed via the first nitrogen negative system N+2 (B − X). The plume temperature was calculated to be about 64 °C, which has a good agreement with water temperature measured by using a thermometer at about 67°C after 15 min at maximum 200 W input power of the plasma jet. [ABSTRACT FROM AUTHOR]

There are two major problems in proton therapy. (1) In comparison with the gamma-ray therapy, proton therapy has only ~ 10% greater biological effectiveness, and (2) the risk of the secondary neutrons in proton therapy is another unsolved problem. In this report, the increase of biological effectiveness in proton therapy has been evaluated with better performance than 11 B in the presence of two proposed nanomaterials of 157 GdF4 and 157 Gd doped carbon with the thermal neutron reduction due to the presence of 157 Gd isotope. The present study is based on the microanalysis calculations using GEANT4 Monte Carlo tool and GEANT4-DNA package for the strand breaks measurement. It was found that the proposed method will increase the effectiveness corresponding to the alpha particles by more than 100% and also, potentially will decrease the thermal neutrons fluence, significantly. Also, in this work, a discussion is presented on a significant contribution of the secondary alpha particles in total effectiveness in proton therapy., (© 2022. The Author(s).)

The main aim of this work is inactivation of Escherichia coli in water using a laboratory-scale radio-frequency atmospheric pressure Argon plasma jet. This bacterium is widely present in the environment, especially in drinking water, and its pathogenic effects are very harmful. For this purpose, an Argon flow rate of 3.5 slm, maximum plasma power of 200 W, and discharge frequency of 13.56 MHz was conducted to generate a uniform plasma plume for water treatment. 150 ml of drinking water contaminated by E. coli was exposed to the radiation of plasma placed about 3 cm within the water, the treatment time varied from 2 to 6 minutes at 100, 150, and 200 W of plasma input power. The temperature of the plume, discharge current and voltage, and electron density were all measured to characterize the plasma. Active species such as excited molecules, ions, and radicals produced in the plasma in water were detected using the optical emission spectroscopy method. The decreasing behavior of live bacteria versus exposure time and plasma jet input power was observed, and finally, at the discharge power of 200 W and 6 min, an effective inactivation was achieved and the number of bacteria reduced from 92×10 4 to less than 1.7 MPN/100 ml.

Research has examined the relationship between religiosity and sexuality but few studies have explored the mechanisms by which sexual variables are influenced by religiosity. The purpose of the present study was to investigate the role of sex guilt in the relationship between religiosity and sexual desire in women. Euro-Canadian (n = 178) and East Asian (n = 361) female university students completed a battery of questionnaires. Higher levels of religious fundamentalism, intrinsic religiosity and spirituality were associated with higher levels of sex guilt in both ethnic groups. Paranormal belief was not associated with sex guilt in either ethnic group. The Euro-Canadian women reported significantly higher levels of sexual desire and significantly less sex guilt than the East Asian women. Among the Euro-Canadian women, sex guilt mediated the relationships between spirituality and sexual desire, and fundamentalism and sexual desire; among the East Asian women, sex guilt mediated the relationships between spirituality and sexual desire, fundamentalism and sexual desire, and intrinsic religiosity and sexual desire. These findings suggest that sex guilt may be one mechanism by which religiosity affects sexual desire among women.