Phytoplankton population dynamics are controlled by the relative rather than absolute timescales of mixing, growth, and loss processes such as sedimentation, grazing, and so on. Here, the vertical distribution and biomass of phytoplankton populations are quantified by two timescale ratios: the Peclet number Pe—the ratio of mixing and sedimentation timescales—and the growth number G—the ratio of...

The effects of thermodynamic non-ideality on the forms of sedimentation equilibrium distributions for several isoelectric proteins have been analysed on the statistical-mechanical basis of excluded volume to obtain an estimate of the extent of protein solvation. Values of the effective solvation parameter delta are reported for ellipsoidal as well as spherical models of the proteins, taken to b...

Photographic analysis was used to examine morphological differences in the oral disc of n=1196 living polyps of Favia speciosa Dana (1846) sampled from four sites in the Wakatobi Marine National Park, Indonesia. Although oral disc size attributes differed significantly between the study sites, the geographic difference accounted for only a small fraction of the morphological variation and did n...

today the industrial wastes are one of the main problems in the developing countries. discharging the industrial wastewater into environment is harmful for human health and other living creatures.thus decreasing of the pollution load of waste waters is an important environmental issue.adsorption of chemical oxygen demand by biomass wastes can be a proper and low cost method for cod removal from...

The association of Cryptosporidium parvum oocysts with suspended particles can alter the oocysts' effective physical properties and influence their transport in aquatic systems. To assess this behavior, C. parvum oocysts were mixed with various suspended sediments under a variety of water chemical conditions, and the resulting settling of the oocysts was observed. Direct microscopic observation...

Multi-proxy approach for the reconstruction of paleo-redox conditions is attempted on a radiocarbon (14C) dated sediment core near the equatorial Indian Ocean. Based on the behavior and distribution of redox sensitive and productivity proxies, study demonstrates prevalence of anoxic bottom water conditions during LGM due to poorly ventilated bottom waters augmented by high surface productivity ...

The genomic DNA of bacteria is highly compacted in one or a few bodies known as nucleoids. In order to understand the overall configuration and physiological activities of the cyanobacterial nucleoid under various growth conditions and the role(s) of each nucleoid protein in clock function, thylakoid membrane-associated nucleoids from the Synechococcus elongatus (se) PCC 7942 strain were isolat...

the transfer and sedimentation in storage dams reduce the volume and damage the life of water reservoirs. due to the importance of water, its storage, and the cost time of constructing reservoirs, especially the scarcity of construncting sites for them, a lot of attentions should be given to the sedimentation of dam reservoirs. it requires the estimate of thew sedimentation and its management. ...

This article deals with experimental and theoretical studies of the sedimentation of polydisperse agarose beads with broad particle size distributions. A light-extinction principle was used to measure the variation of solid concentration in the suspension with time and settling distance. Di4erent experimental conditions have been used to show the in5uence of solid concentration and liquid densi...