Filtration Rates and Scaling in Demosponges

Correction: The energetic cost of filtration by demosponges and their behavioural response to ambient currents.

Sponges (Porifera) are abundant in most marine and freshwater ecosystems, and as suspension feeders they play a crucial role in filtering the water column. Their active pumping enables them to filter up to 900 times their body volume of water per hour, recycling nutrients and coupling a pelagic food supply with benthic communities. Despite the ecological importance of sponge filter feeding, lit...

Individual glomerular filtration rates in renovascular hypertension.

The increased success achieved with cadaveric transplantation makes it unethical to consider using a kidney from a young live donor, especially from a woman in the reproductive period of life. There may still occasionally be circumstances in which a kidney from a parent could reasonably be used, especially if the parent is old enough not to have responsibility for a young family. It is complete...

Error Estimates for Calculated Glomerular Filtration Rates

Glomerular filtration rate (GFR) is a measure of kidney function. It is usually estimated from serum concentrations of cystatin C or creatinine although there has been considerable debate in the literature about (i) the best equation to use and (ii) the variability in the correlation between the concentrations of creatinine and cystatin C. The equations for GFR can be written in a general form ...

Sexual reproductive cycles in Mediterranean demosponges

Copepod feeding currents: flow patterns, filtration rates and energetics.

Particle image velocimetry was used to construct a quasi 3-dimensional image of the flow generated by the feeding appendages of the calanoid copepod Temora longicornis. By scanning layers of flow, detailed information was obtained on flow velocity and velocity gradients. The flow around feeding T. longicornis was laminar, and was symmetrical viewed dorsally, but highly asymmetrical viewed later...