Racial Disparity and the Death Penalty

McAdams examines the rhetoric and data supporting the mass market version of the racial disparity thesis. The system is racist in that it punishes those who kill whites more severely than those who kill blacks

Fat Cats and Thin Kittens: Are People Who Make Large Campaign Contributions Different?

Critics of campaign finance in the United States often direct their fire toward contributors who make large donations. Critics charge that large contributions are unfair, unrepresentative, and undemocratic. Accordingly, they push for "reforms" that would favor small contributions over large, and public money over private donations. Survey data on contributors contradict that stereotype of contributors of large amounts and their effects on American politics. Overall, "fat cats" differ less from contributors of smaller amounts than critics have alleged. The differences that do exist are mostly unsurprising and generally small in magnitude. Survey results show that both policy liberalism and Democratic partisanship are well represented among contributors of large sums.The supporters of McCain-Feingold argue that new restrictions on large contributions will profoundly alter American politics for the better. Their claims have no basis in fact. New laws aimed at restricting large donations in favor of smaller ones will have little effect on practical politics

Noise-based switches and amplifiers for gene expression

The regulation of cellular function is often controlled at the level of gene transcription. Such genetic regulation usually consists of interacting networks, whereby gene products from a single network can act to control their own expression or the production of protein in another network. Engineered control of cellular function through the design and manipulation of such networks lies within the constraints of current technology. Here we develop a model describing the regulation of gene expression, and elucidate the effects of noise on the formulation. We consider a single network derived from bacteriophage $\lambda$, and construct a two-parameter deterministic model describing the temporal evolution of the concentration of $\lambda$ repressor protein. Bistability in the steady-state protein concentration arises naturally, and we show how the bistable regime is enhanced with the addition of the first operator site in the promotor region. We then show how additive and multiplicative external noise can be used to regulate expression. In the additive case, we demonstrate the utility of such control through the construction of a protein switch, whereby protein production is turned ``on'' and ``off'' using short noise pulses. In the multiplicative case, we show that small deviations in the transcription rate can lead to large fluctuations in the production of protein, and describe how these fluctuations can be used to amplify protein production significantly. These novel results suggest that an external noise source could be used as a switch and/or amplifier for gene expression. Such a development could have important implications for gene therapy.Comment: 21 pages, 3 figure