97,713 research outputs found
Observation of explosive collisionless reconnection in 3D nonlinear gyrofluid simulations
The nonlinear dynamics of collisionless reconnecting modes is investigated,
in the framework of a three-dimensional gyrofluid model. This is the relevant
regime of high-temperature plasmas, where reconnection is made possible by
electron inertia and has higher growth rates than resistive reconnection. The
presence of a strong guide field is assumed, in a background slab model, with
Dirichlet boundary conditions in the direction of nonuniformity. Values of ion
sound gyro-radius and electron collisionless skin depth much smaller than the
current layer width are considered. Strong acceleration of growth is found at
the onset to nonlinearity, while at all times the energy functional is well
conserved. Nonlinear growth rates more than one order of magnitude higher than
linear growth rates are observed when entering into the small- regime
Respect for Grizzly Bears: An Aboriginal Approach for Co-existence and Resilience
Aboriginal peoples’ respect for grizzly bear (Ursus arctos) is widely acknowledged, but rarely explored, in wildlife management discourse in northern Canada. Practices of respect expressed toward bears were observed and grouped into four categories: terminology, stories, reciprocity, and ritual. In the southwest Yukon, practices in all four categories form a coherent qualitative resource management system that may enhance the resilience of the bear-human system as a whole. This system also demonstrates the possibility of a previously unrecognized human role in maintaining productive riparian ecosystems and salmon runs, potentially providing a range of valued social-ecological outcomes. Practices of respect hold promise for new strategies to manage bear-human interactions, but such successful systems may be irreducibly small scale and place based
p-topological and p-regular: dual notions in convergence theory
The natural duality between "topological" and "regular," both considered as
convergence space properties, extends naturally to p-regular convergence
spaces, resulting in the new concept of a p-topological convergence space.
Taking advantage of this duality, the behavior of p-topological and p-regular
convergence spaces is explored, with particular emphasis on the former, since
they have not been previously studied. Their study leads to the new notion of a
neighborhood operator for filters, which in turn leads to an especially simple
characterization of a topology in terms of convergence criteria. Applications
include the topological and regularity series of a convergence space.Comment: 12 pages in Acrobat 3.0 PDF forma
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