Factors controlling the spatial distribution of bacterial diversity have been intensely studied, whereas less is known about temporal changes. To address this, we tested whether the mechanisms that underlie bacterial temporal beta-diversity vary across different scales in three marine microbial communities. While seasonal turnover was detected, at least 73% of the community variation occurred a...

We discuss speci cation, frequency domain estimation and application of a exible seasonal long memory time series model based on fractional di erencing. This type of model lends itself to seasonal unit root testing using standard distribution theory with null hypotheses of stationarity and nonstationarity. We apply Wald tests. We suggest periodogram regression estimation for simple models, whic...

background: acute gastroenteritis is responsible observed in all age groups, especially infants and children. the etiology and clinical course of acute gastroenteritis may vary with age and etiological agents. in developing countries, the morbidity and mortality associated with infectious diarrhea is higher in children younger than five-years-of-age. objectives: the aim of this study was to det...

The photochemical equilibrium distribution of oAone below 41 km. is computed for the solstices and equinoxes from recent rocket obscrvatioiis of the solar ultraviolct energy received at the top of the atmosphere. In this study an attempt is made to investigate the important part played by the mean scnsonal transport processes in distributing the ozone below 41 km. in the stratosphere To make su...

The seasonal distribution of the cyprinid herpesvirus 3 (CyHV-3) in Lake Biwa, Japan, was investigated. CyHV-3 was distributed all over the lake 5 years after the first outbreak. The mean concentration of CyHV-3 in water showed annual oscillation, with a peak in the summer and a trough in winter. Our results suggested that CyHV-3 is present at high density in reductive environments, such as ree...

Caspian Sea with an average depth of 27m is the largest enclosed water body in the world. Despite its enormity and valuable biotic and economic resources, investigations on the biota and seawater properties are mosaic at best. In previous studies, the monitoring of the chlorophyll-a concentrations in the Southern Caspian Sea was organized based on satellite data sets however, vertical dis...

BACKGROUND & OBJECTIVES Environmental factors including weather variables may play a significant role in the transmission of dengue. This study investigated the effect of seasonal variation on the abundance of Aedes aegypti and Ae. albopictus larvae and explored the impact of weather variability on dengue transmission in Sisaket, Thailand. METHODS The monthly mosquito larval surveys were carr...

The distribution of conceptions after artificial insemination from a donor was studied in 259 conceptions at an artificial insemination clinic and found to be seasonal. Conception was not influenced by the number of donors or patients attending the clinic, the frequency of inseminations, or medical skill. Conception was more common from early winter until early spring (October to March) with a ...