The histological comparison of the effect of 50mW green and blue laser on the human eye at variable time intervals: an animal model.

Objective: To compare the effects of 50mW green and blue laser pointers on retinal tissue with different exposure durations.

Methods: The experimental, histopathological study was conducted from November 2021 to April 2022 at the Postgraduate Laboratory of the Department of Physiology and Medical Physics, College of Medicine, Mustansiriyah University, Iraq, and comprised adult male mice. They were divided into green group G and blue group B.

Histological assessment of the effect of 50mW red laser on retina at variable time intervals: animal model.

Objective: To assess the histopathological effect of 50milliWatt red laser pointer on mice retinal tissue at variable exposure times.

Methods: The experimental study was conducted in the Postgraduate Laboratory of the Unit of Medical Physics, Department of Physiology, College of Medicine, Mustansiriyah University, Baghdad, Iraq, from November 2020 to April 2021, and comprised albino mice. Histopathological effects on the retinal tissues were evaluated microscopically using conventional haematoxylin and eosin stain just after being exposed to commercially available 50 milliWatt red laser pointers with 630nm wavelength at 1, 2 and 3 minutes, grouped as R1, R2 and R3, respectively.

Experimental investigation into infrasonic emissions from atmospheric turbulence.

Clear air turbulence (CAT) is the leading cause of in-flight injuries and in severe cases can result in fatalities. The purpose of this work is to design and develop an infrasonic array network for early warning of clear air turbulence. The infrasonic system consists of an infrasonic three-microphone array, compact windscreens, and data management system.

Contribution of crosstalk to the uncertainty of electrostatic actuator calibrations.

Crosstalk in electrostatic actuator calibrations is defined as the ratio of the microphone response to the actuator excitation voltage at a given frequency with the actuator polarization voltage turned off to the response, at the excitation frequency, with the polarization voltage turned on. It consequently contributes to the uncertainty of electrostatic actuator calibrations. Two sources of crosstalk are analyzed: the first attributed to the stray capacitance between the actuator electrode and the microphone backplate, and the second to the ground resistance appearing as a common element in the actuator excitation and microphone input loops.