Recent Advances in Understanding Particle Acceleration Processes in Solar Flares

We review basic theoretical concepts in particle acceleration, with particular emphasis on processes likely to occur in regions of magnetic reconnection. Several new developments are discussed, including detailed studies of reconnection in three-dimensional magnetic field configurations (e.g., current sheets, collapsing traps, separatrix regions) and stochastic acceleration in a turbulent environment. Fluid, test-particle, and particle-in-cell approaches are used and results compared. While these studies show considerable promise in accounting for the various observational manifestations of solar flares, they are limited by a number of factors, mostly relating to available computational power. Not the least of these issues is the need to explicitly incorporate the electrodynamic feedback of the accelerated particles themselves on the environment in which they are accelerated. A brief prognosis for future advancement is offered.Comment: This is a chapter in a monograph on the physics of solar flares, inspired by RHESSI observations. The individual articles are to appear in Space Science Reviews (2011

TRADE AND THE ENVIRONMENTAL KUZNETS CURVE: IS SOUTHERN AFRICA A POLLUTION HAVEN?

Evidence that the environmental Kuznets curve (EKC) may be explained by trade patterns casts doubt on the oft-stated conclusion that economic growth automatically leads to environmental improvement. Trends in net exports as a proportion of consumption for both USA and UK trade with SACU were examined for various dirty industries. Some evidence of pollution haven effects is found, although a similar trend for clean industries suggests that this effect is weak. However, even a general shift in manufacturing industries from North to South (as opposed to a shift in specifically dirty industries) may explain the EKC to some extent. Copyright 2005 Economic Society of South Africa.