Analysis of an asymptotic preserving scheme for linear kinetic equations in the diffusion limit

We present a mathematical analysis of the asymptotic preserving scheme proposed in [M. Lemou and L. Mieussens, SIAM J. Sci. Comput., 31 (2008), pp. 334-368] for linear transport equations in kinetic and diffusive regimes. We prove that the scheme is uniformly stable and accurate with respect to the mean free path of the particles. This property is satisfied under an explicitly given CFL condition. This condition tends to a parabolic CFL condition for small mean free paths and is close to a convection CFL condition for large mean free paths. Our analysis is based on very simple energy estimates. © 2010 Society for Industrial and Applied Mathematics.

Genome-wide scan of copy number variation in late-onset Alzheimer's disease.

Alzheimer's disease is a complex and progressive neurodegenerative disease leading to loss of memory, cognitive impairment, and ultimately death. To date, six large-scale genome-wide association studies have been conducted to identify SNPs that influence disease predisposition. These studies have confirmed the well-known APOE epsilon4 risk allele, identified a novel variant that influences disease risk within the APOE epsilon4 population, found a SNP that modifies the age of disease onset, as well as reported the first sex-linked susceptibility variant. Here we report a genome-wide scan of Alzheimer's disease in a set of 331 cases and 368 controls, extending analyses for the first time to include assessments of copy number variation. In this analysis, no new SNPs show genome-wide significance. We also screened for effects of copy number variation, and while nothing was significant, a duplication in CHRNA7 appears interesting enough to warrant further investigation.

New World Gold Cultural Anxiety and Monetary Disorder in Early Modern Spain

Elvira Vilches examines economic treatises, stories of travel and conquest, moralist writings, fiction, poetry, and drama to reveal that New World gold ultimately became a problematic source of power that destabilized Spain’s sense of ...

Understanding the Context for Long-Term Care Planning.

Evolving family structure and economic conditions may affect individuals' ability and willingness to plan for future long-term care (LTC) needs. We applied life course constructs to analyze focus group data from a study of family decision making about LTC insurance. Participants described how past exposure to caregiving motivated them to engage in LTC planning; in contrast, child rearing discouraged LTC planning. Perceived institutional and economic instability drove individuals to regard financial LTC planning as either a wise precaution or another risk. Perceived economic instability also shaped opinions that adult children are ill-equipped to support parents' LTC. Despite concerns about viability of social insurance programs, some participants described strategies to maximize gains from them. Changing norms around aging and family roles also affected expectations of an active older age, innovative LTC options, and limitations to adult children's involvement. Understanding life course context can inform policy efforts to encourage LTC planning.