Narrow Results

In this paper, we utilize a reinforcement learning model for a specialist predator preying upon two types of prey, the noxious models, which are abundant, and the palatable mimics, which are much rarer, in accord with the concept of Batesian mimicry. The latter type of prey resembles the models in appearance so as to derive some protection from the predator who must avoid the unpalatable models. We treat the predator as a slow learning automaton adopting a simple reinforcement learning strategy in order to increase its consumption of palatable prey and reduce the consumption of unpalatable ones. We assume a logistic growth for both models and mimics.

We report a 75-year-old man who presented with a painless friable mass in the index finger pulp mimicking pyogenic granuloma. Complete excision of the mass was done. The radiological and the histopathological findings suggested giant cell tumor of the tendon sheath. The patient had no recurrence at the end of a two-year follow-up. This unusual clinical presentation of the giant cell tumor of the tendon sheath was our study base and adds up to its variant presentation in the literature.

Taking the lower maxillary incisors as an example and the orthodontic forces along the near–far middle direction, the orthodontic forces along the crown–root direction and the orthodontic moment around the tongue–cheek direction as loading condition, the biomechanical simulation of the tooth is carried out by the method of finite element simulation in this paper. The CT images of the skull are segmented and denoised by Mimics. The solid models of teeth, periodontal ligament (PDL), alveolar bone and brackets are established by Gomagic and Solidworks. The material characteristics of the PDL are defined by the two-order Ogden hyperelastic model. Taking the PDL capillary pressure as a criterion for orthodontic safety, combined with the stress response of PDL, the safe orthodontic force range of mandibular central incisors is obtained by ANSYS finite element software.