HIV increases the likelihood that a person will develop TB. Starting them on anti-retroviral therapy (ART) reduces their risk of TB but not to the level in HIV negative people. Since HIV-positive people who are on ART can expect to live a normal life for several decades this raises the possibility that their elevated risk of infection, lasting for a long time, could lead to an increase in the p...

The intrinsic rate of increase is a basic parameter which an ecologist may wish to establish for an insect population. We define it as the rate of increase per head under specified physical conditions, in an unlimited environment where the effects of increasing density do not need to be considered. The growth of such a population is by definition exponential. Many authors, including Malthus and...

Large environmental fluctuations often cause mass extinctions, extirpating species and transforming communities [1, 2]. While the effects on community structure are evident in the fossil record, demographic consequences for populations of individual species are harder to evaluate because fossils reveal relative, but not absolute, abundances. However, genomic analyses of living species that have...

We analyzed databases spanning 50 years, which included retrospective alveolar echinococcosis (AE) case finding studies and databases of the 3 major centers for treatment of AE in Switzerland. A total of 494 cases were recorded. Annual incidence of AE per 100,000 population increased from 0.12-0.15 during 1956-1992 and a mean of 0.10 during 1993-2000 to a mean of 0.26 during 2001-2005. Because ...

The lesser kestrel (Falco naumanni) suffered a sharp population decline over much of its European distribution range in the middle of the twentieth century. Still declining in some areas, the species has recently experienced a notable population recovery in certain regions. We examined the genetic diversity variation in a growing population of lesser kestrels from Central Spain over a 6-year pe...