Laser ultrasonics for nondestructive testing of composite materials and structures: A review.

This paper presents a comprehensive overview of Laser Ultrasonic Testing (LUT) and its applications in composite materials. The working principles of LUT are thoroughly explained, and an assessment of its advantages and drawbacks is provided. The mechanisms of wave generation and detection are described, along with their influence on the capabilities and limitations of LUT.

Design and manufacturing of roller bearing polymeric cages and development of a theoretical model for predicting the roller push-out force.

In the present work, polymeric cages with 18 different pocket geometries are developed to investigate the effects of geometrical parameters and material properties on the amount of roller push-out force. An experimental setup including a specialized injection molding tool is designed and fabricated and three sets of polymeric cages are manufactured using the selected materials (PA46, PA66, PPA). Force measurements are carried out five times on each pocket and three cages for each material are tested.

Comparison the effect of trained and untrained family presence on their anxiety during invasive procedures in an emergency department: A randomized controlled trial.

Objective: The present study was aimed to compare the effect of the trained and untrained family presence on their anxiety during invasive procedures in an emergency department.

Methods: In this randomized controlled clinical trial, 90 patients who were candidates for receiving invasive nursing procedures were selected in an emergency department based on the inclusion criteria, and then were equally assigned into 3 groups by the random minimization method: A ("presence of the trained family member group "), B ("presence of the untrained family member group "), and C ("absence and untrained family member group"). The anxiety level was measured before and after implementation of the procedure using the State-Trait Inventory (STAI).