Complexity, rate, and scale in sliding friction dynamics between a finger and textured surface.

Sliding friction between the skin and a touched surface is highly complex, but lies at the heart of our ability to discriminate surface texture through touch. Prior research has elucidated neural mechanisms of tactile texture perception, but our understanding of the nonlinear dynamics of frictional sliding between the finger and textured surfaces, with which the neural signals that encode texture originate, is incomplete. To address this, we compared measurements from human fingertips sliding against textured counter surfaces with predictions of numerical simulations of a model finger that resembled a real finger, with similar geometry, tissue heterogeneity, hyperelasticity, and interfacial adhesion. Modeled and measured forces exhibited similar complex, nonlinear sliding friction dynamics, force fluctuations, and prominent regularities related to the surface geometry. We comparatively analysed measured and simulated forces patterns in matched conditions using linear and nonlinear methods, including recurrence analysis. The model had greatest predictive power for faster sliding and for surface textures with length scales greater than about one millimeter. This could be attributed to the the tendency of sliding at slower speeds, or on finer surfaces, to complexly engage fine features of skin or surface, such as fingerprints or surface asperities. The results elucidate the dynamical forces felt during tactile exploration and highlight the challenges involved in the biological perception of surface texture via touch

Treatment of the Hemangioma like Osteoblastoma of the Mandible via Resection and Immediate Replantation of the Segment: A case report and review of literature

Introduction: Vascular anomalies are extremely challenging lesions. Management of these lesions vary according to the nature of the lesion.Case Report: We represent an aggressive osteoblastoma that clinically bear a resemblance to vascular lesion.Results: Resection of the lesion and immediate reimplantation of the mandibular body was attained for the patient. 7-year follow up revealed complete healing of the lesion.Conclusion: Resection and Immediate Replantation of the Segment may be an appropriate option for the involved patients for an aggressive osteblastoma with vascular component