Osteochondroma of the proximal humerus with frictional bursitis and secondary synovial osteochondromatosis

We report a case of multiple hereditary exostosis in a 33-year old patient with clinical symptoms of pain and impression of a growing mass of the left shoulder alerting potential risk of malignant transformation of an osteochondroma. Imaging studies illustrated perilesional bursitis surrounding an osteochondroma of the proximal humerus. Malignant transformation was excluded with MRI. Fragments of the osteochondroma were dislocated in the inflammatory synovial bursa illustrating a case of secondary synovial osteochondromatosis

Oral health in Late Pleistocene and Holocene North West Africa

Archaeological sites in North West Africa have yielded a rich record of human occupation, including well dated human burials from the Late Pleistocene Iberomaurusian and early Holocene Capsian periods. The transition broadly coincides with climatic amelioration at the end of the Holocene enabling expansion into slighter dryer inland areas. Here we investigate possible changes in oral health and subsistence behaviours during the transition between the Iberomaurusian (n = 109 individuals) and the Capsian (n = 19 individuals), based on the study of dental remains. Frequencies in oral pathologies (caries, abscesses, periodontal disease and antemortem tooth loss) were studied to assess possible differences between the late Pleistocene and early Holocene. The Late Pleistocene Iberomaurusians were characterised by high caries frequencies (60% of observed teeth). The Capsians displayed very similar patterns in oral pathologies but a slightly lower percentage of carious teeth (49%). The similarity in oral health in Iberomaurusian and Capsian populations is consistent with similarities in diet and oral hygiene. The implication of cultural and biological continuity between the Iberomaurusian and Capsian periods is supported by indicators, such as exploitation of wild plants and snails, tooth evulsion and craniofacial and dental morphology. © 201

Behavioral inferences from the high levels of dental chipping in Homo naledi

Objectives: A variety of mechanical processes can result in ante-mortem dental chipping. In this study, chipping data in the teeth of Homo naledi are compared with those of other pertinent dental samples to give insight into their etiology. Materials and Methods: Permanent teeth with complete crowns evidencing occlusal wear were examined macroscopically. The location, number, and severity of fractures were recorded and compared to those found in samples of two other South African fossil hominin species, as well as in samples of non-human primates (n= 3) and recent humans (n= 7). Results: With 44% of teeth affected, Homo naledi exhibits far higher rates of chipping than the other fossil hominin samples. Specifically, 50% of posterior teeth and 31% of anterior teeth display at least one chip. The maxillary teeth are more affected than the mandibular teeth (45% vs. 43%, respectively), 73% of molar chipping occurs on interproximal surfaces, and right teeth are more often affected than left teeth (50% vs. 38%). Discussion: Results indicate that the teeth of H. naledi were exposed to acute trauma on a regular basis. Because interproximal areas are more affected than buccal, and posterior teeth more than anterior, it is unlikely that non-masticatory cultural behavior was the cause. A diet containing hard and resistant food, or contaminants such as grit, is more likely. The small chip size, as well as steep occlusal wear and cupped dentine on some molars is supportive of the latter possibility. This pattern of chipping suggests H. naledi differed considerably – in terms of diet, environment, and/or specialized masticatory processing— relative to other African fossil hominins

Evaluation of Different Optimal Control Problem Formulations for Solving the Muscle Redundancy Problem

This study evaluates several possible optimal control problem formulations for solving the muscle redundancy problem with the goal of identifying the most efficient and robust formulation. One novel formulation involves the introduction of additional controls that equal the time derivative of the states, resulting in very simple dynamic equations. The nonlinear equations describing muscle dynamics are then imposed as algebraic constraints in their implicit form, simplifying their evaluation. By comparing different problem formulations for computing muscle controls that can reproduce inverse dynamic joint torques during gait, we demonstrate the efficiency and robustness of the proposed novel formulation

Hyperspherical Formulation Of Impurity-Bound Excitons In Semiconductors

A hyperspherical formalism is shown to be an appropriate approach for the investigation of the three-particle complex corresponding to an exciton bound to a Coulomb center in a semiconductor. The ground- and excited-state potential curves and binding energies are calculated as a function of the mass ratio of the hole and electron, and the concept of a critical mass is discussed. The results that we have obtained are in very good agreement with variational calculations for several semiconductor materials