IntroductionPublic and occupational exposure to electromagnetic fields due to the growing trend of electronic devices may cause adverse effects on human health. This paper describes the risk of mutation and sexual trauma and infertility in masculine sexual cell by mobile phone radiations.MethodsIn this study, we measured the emitted dose from a radiofrequency device, such as switching high voltage at different frequencies using a scintillation detector. The switching high voltage power supply (HVPS) was built for the Single Photon Emission Computed Tomography (SPECT) system. For radiation dosimetry, we used an ALNOR scintillator that can measure gamma radiation. The simulation was performed by MATLAB software, and data from the International Commission on Non-Ionizing Radiation Protection (ICNIRP) were used to verify the simulation.ResultsWe investigated the risks that result from the waves, according to a report by International Commission on Non Ionizing Radiation Protection (ICNIRP), to every organ of the body is defined by the beam and electromagnetic radiation from this electronic device on people. The results showed that the maximum personal dose over a 15-min period working at the mentioned HVPS did not exceed 0.31 μSV/h (with an aluminum shield). So, according to other sources of radiation, continuous working time of the system should not be more than 10 hours. Finally, a characteristic curve for secure working with modules at different frequencies was reported. The RF input signal to the body for maximum penetration depth (δ) and electromagnetic energy absorption rate (SAR) of biological tissue were obtained for each tissue.ConclusionThe results of this study and International Commission of Non Ionization Radiation Protection (ICNIRP) reports showed the people who spend more than 50 minutes a day using a cell phone could have early dementia or other thermal damage due to the burning of glucose in the brain.

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Scatter coincidences contain hidden information about the activity distribution on the positron emission tomography (PET) imaging system. However, in conventional reconstruction, the scattered data cause the blurring of images and thus are estimated and subtracted from detected coincidences. List mode format provides a new aspect to use time of flight (TOF) and energy information of each coincidence in the reconstruction process. In this study, a novel approach is proposed to reconstruct activity distribution using the scattered data in the PET system. For each single scattering coincidence, a scattering angle can be determined by the recorded energy of the detected photons, and then possible locations of scattering can be calculated based on the scattering angle. Geometry equations show that these sites lie on two arcs in 2D mode or the surface of a prolate spheroid in 3D mode, passing through the pair of detector elements. The proposed method uses a novel and flexible technique to estimate source origin locations from the possible scattering locations, using the TOF information. Evaluations were based on a Monte-Carlo simulation of uniform and non-uniform phantoms at different resolutions of time and detector energy. The results show that although the energy uncertainties deteriorate the image spatial resolution in the proposed method, the time resolution has more impact on image quality than the energy resolution. With progress of the TOF system, the reconstruction using the scattered data can be used in a complementary manner, or to improve image quality in the next generation of PET systems.

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Tracheostomy can be performed surgically or by percutaneous (percutaneous dilatory tracheostomy, PDT) methods, and it may be used early or late. In a 3-month follow-up, all patients who underwent tracheostomy in Semnan in 2013 were evaluated for complications of tracheostomy considering the method used and the timing of operation. A total of 55 patients underwent tracheostomy (26 cases surgery, 29 cases PDT, 30 cases early, and 25 cases late based on 14 days reference). The mean durations of operation were 19.19 ± 5.78 min in the surgery method and 4.7 ± 2.42 min in the PDT method ( < 0.001). The mean durations of the need for ventilator after the tracheostomy were 10.7 ± 9.25 and 18.6 ± 14.39 days in early and late tracheostomy, respectively ( = 0.024). The mean intensive care unit (ICU) stay were 12.70 ± 10.24 and 23.44 ± 18.49 days ( = 0.014) and the mean hospital stay were 16.04 ± 10.88 and 23.48 ± 18.47 days, respectively ( = 0.100). Short-term complications were observed in six cases (10.09 %) in the surgery group, including emphysema (two), bleeding (two), wound infection (one), and clot formation inside the tube (one). Only one complication (bleeding) occurred in one case in the PDT group. After 3 months, 21 patients survived. Compared with surgery, the most important advantage of the PDT method was its shorter duration of surgery. Nearly half of the patients underwent tracheostomy late, while the majority of the patients in the late group were referred from internal ICU. No major and minor complications were noted during the procedure, as well as no tracheostomy-related deaths were observed. Early tracheostomy was shown to be superior to late, reducing the time of mechanical ventilation and ICU or hospital stay.