Since 2008, kidney exchange in America has grown in part from the incorporation of nondirected donors in transplant chains rather than simple exchanges. It is controversial whether these chains should be performed simultaneously 'domino-paired donation', (DPD) or nonsimultaneously 'nonsimultaneous extended altruistic donor, chains (NEAD). NEAD chains create 'bridge donors' whose incompatible re...

Quad-morphing is a new technique used for generating quadrilaterals from an existing triangle mesh. Beginning with an initial triangulation, triangles are systematically transformed and combined. An advancing front method is used to determine the order of transformations. An all-quadrilateral mesh containing elements aligned with the area boundaries with few irregular internal nodes can be gene...

Tuberculosis outbreaks originating in prisons, mines, or hospital wards can spread to the larger community. Recent proposals have targeted these high-transmission institutional amplifiers by improving case detection, treatment, or reducing the size of the exposed population. However, what effects these alternative proposals may have is unclear. We mathematically modeled these control strategies...

Background The assessment of newly acquired human immunodeficiency virus type 1 (HIV-1) infection, or incidence, provides important information for public health programs and is crucial for understanding the status of the epidemic and providing information regarding the impact of prevention measures. The aim of this study was to evaluate the ability of the assay DS-EIA-HIV-AB-TERM correctly ide...

A modification of the popular unification model for Seyfert galaxies is proposed, which takes into account recent observational findings on the statistical properties of both type 1 and type 2 Seyferts. In the proposed scenario, Compton–thick Seyfert 2 galaxies are those sources observed through compact, thick matter (the ‘torus’), while Compton–thin/ intermediate Seyfert galaxies are obscured ...

An age-structured model is used to study the possible impact of drug treatment of infections with the human immunodeficiency virus type 1 (HIV-1) on evolution of the pathogen. Inappropriate drug therapy often leads to the development of drug-resistant mutants of the virus. Previous studies have shown that natural selection within a host favors viruses that maximize their fitness. By demonstrati...

OBJECTIVE To determine the prevalence and characteristics of clinical handover incidents that occurred across a medium-size UK hospital. DESIGN A retrospective review of 36 consecutive months of data from the hospital electronic database of critical incidents was conducted. MAIN OUTCOME MEASURES Number of incidents reported, characterization of handover incidents according to clinical setti...