Study of human adaptation to extreme environments is important for understanding our cultural and genetic capacity for survival. The Pucuncho Basin in the southern Peruvian Andes contains theâ€¦ (More)

We use symmetry methods to study the model of growth of a tumour of the brain proposed by Wein and Koplow (Mathematical modeling of brain cancer to identify promising combination treatments,â€¦ (More)

The symmetry approach to the determination of Jacobiâ€™s last multiplier is inverted to provide a source of additional symmetries for the Euler-Poinsot system. These additional symmetries are nonlocal.â€¦ (More)

We investigate the symmetry properties of a pair of Ermakov equations. The system is superintegrable and yet possesses only three Lie point symmetries with the algebra sl(2, R). The number of pointâ€¦ (More)

The integrability properties of the field equation Lxx = F (x)L 2 of a spherically symmetric shearâ€“free fluid are investigated. A first integral, subject to an integrability condition on F (x), isâ€¦ (More)

We reformulate the dynamics of homogeneous cosmologies with a scalar field matter source with an arbitrary self-interaction potential in the language of jet bundles and extensions of vector fields.â€¦ (More)

The last multiplier of Jacobi provides a route for the determination of families of Lagrangians for a given system. We show that the members of a family are equivalent in that they differ by a totalâ€¦ (More)