abstract uranium as a natural radioactive heavy metal widely disperses throughout the earth's crust. in many cases, the natural abundance has been re-distributed due to anthropogenic activities, resulting in radionuclide contamination in groundwater and surface soil. uranium through the plant uptake can enter the chain. the degree of speciation of radio nuclides in soils in areas with differing...

Honey bees (Apis mellifera anatolica) were subjected to sequential trials where they were given the choice between a feature-positive and a feature-negative feeding plate. The 'feature' being manipulated is the presence of a single blue circle among three circles marking the location of a small sucrose reward. That is, a 'feature-negative' target had three white circles, while a 'feature-positi...

Sequential feeding (SF) consists of splitting energy (E) and protein/calcium (P) fractions temporally, improving the feed conversion ratio (FCR) of hens compared with a continuous distribution during the day. In a previous study, the E fraction (with a low level of protein) was provided in the morning, whereas the P fraction (with low level of energy) was given in the afternoon. However, there ...

The influence of plants in the diversification herbivorous insects, specifically those that utilize moribund and dead hosts, is little explored. Host shifts are expected because effectiveness toxic secondary chemicals lessened by decay plants. Feeding on also releases insect lineages from diversifying within a particular plant lineage. Thus, phylogenetic constraints lineage imposed host diminis...

fifty street dust samples were collected from southern and eastern parts of tehran, the capitalof iran. samples were collected during summer under dry and stable weather conditions. total concentrationsof copper (cu), cadmium (cd), lead (pb), chromium (cr), nickel (ni), zinc (zn), iron (fe), manganese (mn)and lithium (li) were determined. ten samples were then selected for characterization, met...

the seasonal abundance patterns of the cotton aphid, aphis gossypii glover, in cotton fields at gorgan in northern iran were studied during two growing seasons of 2002 and 2003. the spatial distribution of different developmental stages and morphs of the aphid was described by fitting data to poisson (random) and negative binomial (aggregated) dis-tributions, and calculating the dispersion indi...

the chemical speciation of heavy metals (arsenic, chromium, copper, lead, zinc and tin) in the sediments offormer tin mining catchment bestari jaya, peninsular malaysia was determined by using the latest version of the community bureau of reference, usually called the bcr 3-step sequential extraction procedure. furthermore, a fourth step was introduced for digestion and analysis of the residue....

knowledge of the probable origin and behaviour of arsenic certainly gives valuable insights into the potential for transfer in the environment and of the risks involved in mining sites. sequential extraction analyses are common experiments often used to study the origin and behaviour of potentially toxic elements. the method, however, presents some deficiencies, including labor-intensive proced...

This study seeks to investigate the effect of restricted feeding regimes at different rate on growth performance of Clarias gariepinus using static and flow through system. Fingerlings were divided into six batches for each systems with the first and second batch fed at 5% body weight (BW) every day and every other day respectively, the third and fourth batch were fed 10% BW every day and every...

We assess the effectiveness of applying information theory to the characterization and quantification of the affects of anthropogenic vessel noise on humpback whale (Megaptera novaeangliae) vocal behavior in and around Glacier Bay, Alaska. Vessel noise has the potential to interfere with the complex vocal behavior of these humpback whales which could have direct consequences on their feeding be...