Agent-based crowd simulations are used for modelling building and space usage, allowing designers to explore hypothetical real-world scenarios, including extraordinary events such as evacuations. Existing work which engages virtual reality (VR) as a platform for crowd simulations has been primarily focussed on the validation of simulation models through observation; the use of interactions such as gaze to enhance a sense of immersion; or studies of proxemics. In this work, we extend previous studies of proxemics and examine the effects of varying crowd density on user experience and behaviour. We have created a simulation in which participants walk freely and perform a routine manual task, whilst interacting with agents controlled by a typical social force simulation model. We examine and report the effects of crowd density on both affective state and behaviour. Our results show a significant increase in negative affect with density, measured using a self-report scale. We further show significant differences in some aspects of user behaviours, using video analysis, and discuss how our results relate to VR simulation design for mixed human-agent scenarios.

Automated wireless sensing of force dynamics during a visuomotor control task was used to rapidly assess residual motor function during finger pinch (right and left hand) and lower lip compression in a cohort of seven adult males with chronic, unilateral middle cerebral artery (MCA) stroke with infarct confirmed by anatomic magnetic resonance imaging (MRI). A matched cohort of 25 neurotypical adult males served as controls. Dependent variables were extracted from digitized records of ‘ramp-and-hold’ isometric contractions to target levels (0.25, 0.5, 1, and 2 Newtons) presented in a randomized block design; and included force reaction time, peak force, and dF/dtmax associated with force recruitment, and end-point accuracy and variability metrics during the contraction hold-phase (mean, SD, criterion percentage ‘on-target’). Maximum voluntary contraction force (MVCF) was also assessed to establish the force operating range. Results based on linear mixed modeling (LMM, adjusted for age and handedness) revealed significant patterns of dissolution in fine force regulation among MCA stroke participants, especially for the contralesional thumb-index finger followed by the ipsilesional digits, and the lower lip. For example, the contralesional thumb-index finger manifest increased reaction time, and greater overshoot in peak force during recruitment compared to controls. Impaired force regulation among MCA stroke participants during the contraction hold-phase was associated with significant increases in force SD, and dramatic reduction in the ability to regulate force output within prescribed target force window (±5% of target). Impaired force regulation during contraction hold-phase was greatest in the contralesional hand muscle group, followed by significant dissolution in ipsilateral digits, with smaller effects found for lower lip. These changes in fine force dynamics were accompanied by large reductions in the MVCF with the LMM marginal means for contralesional and ipsilesional pinch forces at just 34.77% (15.93 N vs. 45.82 N) and 66.45% (27.23 N vs. 40.98 N) of control performance, respectively. Biomechanical measures of fine force and MVCF performance in adult stroke survivors provide valuable information on the profile of residual motor function which can help inform clinical treatment strategies and quantitatively monitor the efficacy of rehabilitation or neuroprotection strategies.

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A wireless biomechanical sensing technology, known as ForceWIN10, was developed and tested in our laboratory to provide clinicians and researchers with an integrated solution to conduct real-time bedside diagnostics and neurotherapeutics of muscle force dynamics among key motor control systems (i.e., hand-digits, orofacial) suitable for a wide range of clinical populations across the lifespan who have sustained injuries (i.e., cerebrovascular stroke, traumatic brain injury) or manifest progressive neuromotor disease (i.e., Parkinson's disease, amyotrophic lateral sclerosis, etc.). ForceWIN10 provides wireless sensor technology and data acquisition, custom test protocol creation, visuomotor stimulus control, analysis of isometric force signals, and file and database management.

The success of endodontic treatment depends on the location of all root canals, so that they can be cleaned, shaped and filled. Therefore, the objective of this article was to review the literature on existing alternatives to facilitate the localization and negotiation of second canal in mesiobuccal root (MB2) and to illustrate, through two clinical cases, some of these alternatives. In case one we show the management of a biopulpectomy of an upper molar. In the second case, a pulp necrosis, with fistula in which there was only regression after localization, negotiation and intracanal medication of MB2. It should be emphasized that in the maxillary molars, the endodontist should always go in search of MB2, using all available tools, accessible and necessary for each case and this conduct is determinant for the endodontic success of many treatments.