Survival probability for high mass diffraction

Based on the calculation of survival probabilities, we discuss the problem of extracting the value of $G_{3P}$, the triple Pomeron 'bare' coupling constant, by comparing the large rapidity gap single high mass diffraction data in proton-proton scattering and $J/\Psi$ photo and DIS production. For p-p scattering the calculation in a three amplitude rescattering eikonal model, predicts the survival probability to be an order of magnitude smaller than for the two amplitude case. The survival probabilities calculation for photo and DIS $J/\Psi$ production is made in a dedicated model. In this process we show that, even though its survival probability is considerably larger than in p-p scattering, its value is below unity and cannot be neglected in the data analysis. We argue that, regardless of the uncertainties in the suggested procedure, its outcome is important both with regards to a realistic estimate of $G_{3P}$, and the survival probabilities relevant to LHC experiments.Comment: 17 pages, 8 pictures and one tabl

Prevention of colorectal cancer by combining early detection and chemoprevention

Colorectal cancer is a major cause of cancer-related mortality. Most colorectal cancers arise in precursor lesions over a number of years. The carcinogenetic pathway is modulated by a wide array of genetic and epigenetic factors. Two major approaches to halting carcinogenesis are chemoprevention and early detection. Chemoprevention is an attractive emerging option-advances in understanding the carcinogenetic pathways and progress in evaluating various putative agents are promising. However, several issues regarding efficacy, safety, and acceptability require answers before an ideal agent can come into widespread use. Early detection and removal of precursor lesions show promise in reducing disease burden. Although the concept has been around and has been widely advocated for several years, participation in screening remains low. The ideal test in terms of practicality, accuracy, and safety is still debated. This article reviews the recent literature related to screening and chemoprevention of colorectal cancer. Copyright © 2009 by Current Medicine Group LLC