Background. It is highly cost effective to detect a seasonal trend in tuberculosis in order to optimize disease control and intervention. Although seasonal variation of tuberculosis has been reported from different parts of the world, no definite and consistent pattern has been observed. Therefore, the study was designed to find the seasonal variation of tuberculosis in Delhi, India. Methods. R...

We describe the reproductive biology of the coypu, Myocastor coypus (Molina, 1782), in western Japan, as an attempt to contribute to an efficient population control program of the coypu population. A total of 212 specimens (113 males and 99 females) were collected in the Tottori prefecture from February 2010 to January 2012. From the age estimation based on body weight and molar eruption patter...

Satellite imagery has been used to acquire seasonal terminus positions of tidewater Hubbard Glacier, Alaska, USA, from 1992 to 2006. During this 15 year time period, the width-averaged advance of the entire terminus has been 620m at a mean rate of 35ma. Seasonal fluctuation of the terminus ranges from 150 to 200m on average and varies spatially. A section of the terminus, near a narrow gap wher...

The assumption that natural selection is an Optlmlslllg process, means that reproductive seasonality in mammals evolved to maximise gene survival. Although the constraints usually imposed on optimality theory are applicable, it can be assumed that periodicity in reproduction represents an adaptation to fluctuation in the availability of potentially limiting resources. In areas where these fluct...

The prediction of the lineage dynamics of influenza B viruses for the next season is one of the largest obstacles for constructing an appropriate influenza trivalent vaccine. Seasonal fluctuation of transmissibility and epidemiological interference between the two major influenza B lineages make the lineage dynamics complicated. Here we construct a parsimonious model describing the lineage dyna...

We consider the problem of explaining the emergence and evolution of cooperation in dynamic network-structured populations. Building on seminal work by Poncela et al., which shows how cooperation (in one-shot prisoner's dilemma) is supported in growing populations by an evolutionary preferential attachment (EPA) model, we investigate the effect of fluctuations in the population size. We find th...

Development of ectotherms is highly temperature dependent. Studies using variable thermal environments can improve ecological relevance of data because organisms naturally face day-to-day stochastic temperature fluctuations as well as seasonal changes in the amplitude of such daily fluctuations. The objective of this study was to investigate if, and to what extent, the use of constant temperatu...

We consider a diffusion model with neutral alleles whose population size is fluctuating randomly. For this model, the effects of fluctuation of population size on the effective size are investigated. The effective size defined by the equilibrium average heterozygosity is larger than the harmonic mean of population size but smaller than the arithmetic mean of population size. To see explicitly t...