Usability of an augmented reality bedtime routine application for autistic children.

Sleep problems are highly prevalent in autism and negatively impact the physical and mental health of children and their caregivers. Sleep education programs are often recommended as a first line-treatment to help parents implement healthy sleeping habits and a bedtime routine at home; however, the accompanying paper-based toolkits used in the bedtime routines have limitations related to engagement and adherence. To address these gaps, we iteratively developed and tested the usability of an augmented reality (AR) bedtime routine application.

Factors influencing acceptance and trust of chatbots in juvenile offenders' risk assessment training.

Introduction: Research has identified simulation-based training with chatbots and virtual avatars as an effective educational strategy in some domains, such as medicine and mental health disciplines. Several studies on interactive systems have also suggested that user experience is decisive for adoption. As interest increases, it becomes important to examine the factors influencing user acceptance and trust in simulation-based training systems, and to validate applicability to specific learning tasks.

The development of a virtual simulator for training neurosurgeons to perform and perfect endoscopic endonasal transsphenoidal surgery.

Background: A virtual reality (VR) neurosurgical simulator with haptic feedback may provide the best model for training and perfecting surgical techniques for transsphenoidal approaches to the sella turcica and cranial base. Currently there are 2 commercially available simulators: NeuroTouch (Cranio and Endo) developed by the National Research Council of Canada in collaboration with surgeons at teaching hospitals in Canada, and the Immersive Touch. Work in progress on other simulators at additional institutions is currently unpublished.

Point and ring defects in nematics under capillary confinement.

The textures exhibited by nematic liquid crystals confined to cylindrical capillaries under homeotropic anchoring have been studied for nearly thirty years. One of the reasons behind this maintained interest is that the processing of many high-performance fibers including carbon fibers and spider silks involves these textures. Three of these textures, the planar radial with line defect, the planar polar with two line defects (PPLD), and the escape radial (ER), are relatively well understood.

Ringlike cores of cylindrically confined nematic point defects.

Nematic liquid crystals confined in a cylindrical capillary and subjected to strong homeotropic anchoring conditions is a long-studied fundamental problem that uniquely incorporates nonlinearity, topological stability, defects, and texture physics. The observed and predicted textures that continue to be investigated include escape radial, radial with a line defect, planar polar with two line defects, and periodic array of point defects. This paper presents theory and multiscale simulations of global and fine scale textures of nematic point defects, based on the Landau-de Gennes tensor order parameter equations.

Microscopic observations and simulations of Bloch walls in nematic thin films.

We study Bloch wall defects formed by quenching nematic thin films from planar anchoring to homeotropic anchoring through a temperature-driven anchoring transition. The director profiles of the walls are directly visualized using fluorescence confocal polarizing microscopy, and shown to agree well with the simulation based on the Frank elasticity theory. A pure twist wall exists if the ratio of sample thickness to surface extrapolation length p is smaller than or close to 1; while a diffuse Bloch wall is obtained if p is much greater than 1.

Dynamic interactions between nematic point defects in the spinning extrusion duct of spiders.

Spider silk fibers have remarkable mechanical properties as a result of an ultraoptimized spinning process. Silk fibers are spun from a lyotropic nematic liquid crystalline anisotropic fluid phase which undergoes significant structural changes throughout the spinning pathway. In the silk extrusion duct, those structural changes are expected to be driven by elastic-mediated interactions between point defects.

Chiral front propagation in liquid-crystalline materials: Formation of the planar monodomain twisted plywood architecture of biological fibrous composites.

Biological fibrous composites commonly exhibit an architecture known as twisted plywood, which is similar to that of the cholesteric liquid-crystalline mesophases. The explanation for the structural similarity is that biological fibrous composites adopt a lyotropic cholesteric liquid-crystalline phase during their formation process. In this work, a mathematical model based on the Landau-de Gennes theory of liquid crystals has been developed to reproduce the process by which long chiral fibrous molecules form the twisted plywood structures observed in biological composites.