Introduction: Electrical impedance of tissues on low frequencies includes useful information about functional and structural changes in tissues. This property is used in Electrical Impedance Tomography (EIT) imaging modality for the detection of lesions in tissues.Objective: The goal of this article is to study changes in electrical impedance of tissues in the presence of gold nanoparticles.Materials and Methods: Spherical gold nanoparticles with size of 20-25 nm were synthesized with Turkevich method. Size distribution and shape of nanoparticles were characterized by transmission electron microscopy (TEM). Electrical impedance of two types of phantoms (chicken fat and muscle paste tissues) was measured by 4-electrode method with and without gold nanoparticles.Results: Results demonstrate a reduction in electrical impedance of tissues in the presence of gold nanoparticles. However, this reduction is not the same for fat and muscle tissues. Reductions in resistive impedance are  for fat and muscle tissues on the frequency of 1 KHz, respectively. A reduction in electrical impedance is accompanied by a rise in electrical conductance leading to increase in EIT signal.Conclusion: As signal enhancement is different for fat and muscle tissues; presence of gold nanoparticles could be used to improve EIT image contrast.

Background: Radiation protection is an important principle in some wards of the hospital such as radiology, catheterization laboratory and operating room. Due to the increasing use of radiation in the operating room, there is a need to design an accurate and appropriate tool to evaluate the radiation protection capability of operating room personnel.Objective: This study aims to test the psychometric properties of a questionnaire on radiation protection capability. Material and Methods:This cross-sectional study was conducted in two stages. The first stage was designing items based on the review of available literature, and the second stage was measuring the validity and reliability of the questionnaire using face validity and content validity Content Validity Index (CVI) and Content Validity Ratio (CVR). Then the questionnaire was filled out by 200 operating room nurses to evaluate the construct validity by Principal Component Analysis method. Reliability of the questionnaire was evaluated by test-retest and Cronbach's alpha analysis method.Results: Due to the results, test-retest correlation coefficient was 0.912, and Cronbach's alpha coefficient was 0.824, indicating a desirable internal consistency. Conclusion:This study introduces a valid and reliable questionnaire for evaluating the radiation protection capability of operating room nurses.

Entanglement is an integral part of the quantum information processing and quantum computations that have been proposed to take place in the brain. Microtubules and photons are agents that have been mainly discussed as related factors in quantum computations of the brain. In the present article, we report the dynamical behaviour of entanglement between Tubulin states and bio-photons and their implication for the previously proposed memory storage in Microtubules. We had used Von-Neumann entropy to quantify entanglement and we showed that the degree of such entanglements depend on coupling constant (  ), detuning (  ) and number of bio-photons. The entanglement between bio-photon and tubulin in human brain is controlled by coupling constant in different parts of brain.

This study aims to make a phantom to verify dose distribution and compare two techniques of radiation therapy, including 3D conventional radiotherapy (3D-CRT) and modulated photon radiotherapy (IMRT). For treatment of brain cancer, physicians have to prescribe radiation therapy to involved patients so that organs at risk receive unwanted dose causing them to be damaged. To know precise dose delivered into them and evaluate treatment-planning system (TPs), it is necessary to do dosimetry in the phantom owing to difficulties of dosimetry in human. It is important to make a phantom with characteristics similar to humans and ability to compute dose and dose distribution in desired organs and tissue. Thus, there is possibility to compute dose in different parts, including doses delivered in ears, eyes, stem brain and optic nerve. Furthermore, this phantom has to provide this opportunity to investigate whether some techniques of radiation therapy such as 3D-CRT or IMRT depend on the size or location of tumors. To this end, a low workload, easy-to-set-up, lightweight, and transportable phantom was designed, and made from Polylactic acid (PLA) in dimensions 23×24×32 cm 3 . The phantom consists of brain, tumors in different dimeters, including 2, 4, 6 cm and also parts for eyes and ears to locate TLDs. Head, brain and tumors are able to open so that they can be filled with polymer gel dosimetry making possible record dose distribution in three-dimensions (3D) and sharp dose gradients.