A Variational Principle for the Asymptotic Speed of Fronts of the Density Dependent Diffusion--Reaction Equation

We show that the minimal speed for the existence of monotonic fronts of the equation $u_t = (u^m)_{xx} + f(u)$ with $f(0) = f(1) = 0$, $m >1$ and $f>0$ in $(0,1)$ derives from a variational principle. The variational principle allows to calculate, in principle, the exact speed for arbitrary $f$. The case $m=1$ when $f'(0)=0$ is included as an extension of the results.Comment: Latex, postcript figure availabl

Cyber-Politics: How New Media has Revolutionized Electoral Politics in the United States

This paper addresses the impact new media tools have on different segments of the electoral process in the United States. Specifically, it looks at the impact new media has by providing information, influencing the news cycle and setting agendas, shaping public opinion, providing more fundraising opportunities, increasing political participation and youth voter turnout, and changing election results. This paper does so by drawing on systematic studies, data from the Pew Research Center, and case studies, specifically that of the 2008 Presidential Election. This analysis is unique in that it uses very current information, focusing on the 2008 election, as this was the first election in which new media was fully integrated into campaign strategies. It is also unique in that it analyzes several types of new media including social networks, blogging, campaign websites, and Internet fundraising. These findings suggest that new media does influence and shape the course of the electoral process in the United States through the six aspects of the electoral process presented in this paper

Neuroscience and Juvenile Justice

Recent advances in the field of neuroscience, especially improved magnetic resonance imaging (MRI) techniques, are providing scientists and decision-makers with an increasingly complex understanding of how our brains develop from birth to adulthood. While these studies are still in their infancy, they have already made it clear that the brain typically continues to develop long after the point at which an individual becomes a legal adult (i.e., at age 18), and that the slow maturation process that plays out in the social context is mirrored by a slow maturation process at the neural level. Despite the tentative nature and unsettled meaning of this information (i.e., we do not yet understand the actual link between brain structure and behavior), neuroscience is increasingly implicated in long-standing debates about the treatment of juveniles in the criminal justice system and the extent to which adolescents can be held legally responsible for their acts. To date, the most notable example of this trend has been Roper v. Simmons, in which the Supreme Court banned the death penalty for offenders under the age of 18. The case revolved around the trial, sentencing, and habeas corpus petition of Christopher Simmons, who brutally murdered an elderly woman during the course of a burglary when he was 17 years old. The Court held that although the execution of juveniles was once considered acceptable in American society, a national consensus had emerged that such a punishment was cruel and unusual and, thus, in violation of the Eighth Amendment. The majority agreed with Simmons’ claim that adolescents do not possess the emotional, intellectual, or biological maturity necessary to be reliably classified among the worst offenders. Although adolescents should certainly be punished for their crimes, they should not pay the ultimate price for impulses that they were unable to control. Simmons’ argument was premised largely on new brain imaging evidence suggesting that the adolescent brain is not as well developed as the adult brain