this research that was made on 66 cyclones in wet periods of midwest of iran in a given period (1973-2003) shows that in intense wet periods, cyclogensis centers of mediterranean sea, sudan, red sea and mesopotamia were severely active and have been very effective in rainfall of study area. such systems in general, with respect to dominant synoptic patterns, enters into study area from three ma...

The cumulative effects of climate warming on herbivore vital rates and population dynamics are hard to predict, given that the expected effects differ between seasons. In the Arctic, warmer summers enhance plant growth which should lead to heavier and more fertile individuals in the autumn. Conversely, warm spells in winter with rainfall (rain-on-snow) can cause 'icing', restricting access to f...

The aim of this work is to analyze whether there is a seasonal prevalence of parasites in dog feces from public squares in Mar del Plata city, Argentina, and to evaluate the climatic conditions that promote the development of parasites and allow the transmission to people. The study was performed in 21 squares from June 2001 to May 2002. Samples were processed by the Willis technique. Differenc...

Measurements of air and soil temperatures and xylem pressure were made on 17-year-old orchard trees and on 5-year-old potted trees of walnut (Juglans regia L.). Cooling chambers were used to determine the relationships between temperature and sugar concentration ([glucose] + [fructose] + [sucrose], GFS) and seasonal changes in xylem pressure development. Pressure transducers were attached to tw...

BACKGROUND There is evidence that acute myocardial infraction (aMI) occurs more frequently in certain seasons and months of the year. Recently various infectious agents have been implicated in atherogenesis. In the present study we recorded the seasonal distribution of aMI and evaluated its relation to acute systemic infections (AIs). METHODS The study included 1196 patients with aMI hospital...

Pathogenic hantaviruses (family Bunyaviridae, genus Hantavirus) are rodent-borne viruses causing hemorrhagic fever with renal syndrome (HFRS) in Eurasia. In Europe, there are more than 10,000 yearly cases of nephropathia epidemica (NE), a mild form of HFRS caused by Puumala virus (PUUV). The common and widely distributed bank vole (Myodes glareolus) is the host of PUUV. In this study, we aim to...

Surface ozone (O3) and its precursor’s gases (nitrogen monoxide (NO), nitrogen dioxide (NO2), nitrogen oxides (NOx), carbon monoxide (CO), methane (CH4) and non-methane hydrocarbons (NMHCs), and sulfur dioxide (SO2) were measured in Yanbu, Saudi Arabia from January 2004-December 2004. The annual average concentrations of O3, NO, NO2, NOx, SO2, CO, CH4, TNMHCs and THC were 22.51 ppb, 15.58 ppb, ...

PURPOSE Understanding seasonal variation in physical activity is important for informing public health surveillance and intervention design. The aim of the current study was to describe seasonal variation in children's objectively measured physical activity and sedentary time. METHODS Data are from the UK Millennium Cohort Study. Participants were invited to wear an accelerometer for 7 d on f...

BACKGROUND AND AIMS Photosynthetic plasticity in response to a range of environmental factors that include [CO(2)], water availability, light intensity and temperature, is ubiquitous among plants with crassulacean acid metabolism (CAM). The present study examined how seasonal changes in light availability, as experienced by greenhouse CAM crops in northern latitude regions, influence diel carbo...