Inertia Induces Strong Orientation Fluctuations of Nonspherical Atmospheric Particles.

The orientation of nonspherical particles in the atmosphere, such as volcanic ash and ice crystals, influences their residence times and the radiative properties of the atmosphere. Here, we demonstrate experimentally that the orientation of heavy submillimeter spheroids settling in still air exhibits decaying oscillations, whereas it relaxes monotonically in liquids. Theoretical analysis shows that these oscillations are due to particle inertia, caused by the large particle-fluid mass-density ratio. This effect must be accounted for to model solid particles in the atmosphere.

Avulsion fracture of the origin of the brachioradialis muscle.

Avulsion fracture of the brachioradialis muscle from its origin on the lateral supracondylar ridge of the humerus has not previously been reported in the literature. In this article, we present the case of a patient who sustained a grade I open avulsion fracture of the lateral supracondylar ridge of the humerus. The mechanism by which this fracture occurred is proposed on the basis of the structure and function of the brachioradialis muscle.