Metal-organic frameworks offer tremendous potential for efficient separation of molecular mixtures. Different pore sizes and suitable functionalizations of the framework allow for an adjustment of the static selectivity. Here we report membranes which offer dynamic control of the selectivity by remote signals, thus enabling a continuous adjustment of the permeate flux. This is realized by assem...

INTRODUCTION. Hyperparathyroidism is a common finding in patients with renal insufficiency and parathyroid hormone (PTH) is considered a uremic toxin responsible for many of the abnormalities of the uremic state and bone disease. The aim of this study was to investigate the influence of permeability of low-flux versus high-flux dialysis membranes on intact PTH during hemodialysis in children. M...

A coagulation–microfiltration (MF) system has the potential to remove natural organic matter and mitigate membrane fouling. The effect of flocculation conditions on MF performance was investigated using three membrane modules including stirred cell, dead-end MF, and submerged MF. The experimental results were analysed in terms of filterability, particle size, and floc structure as represented b...

The ability ofFundulus kansae to live in both fresh water and 200% sea water, even when hypophysectomized, makes it a convenient experimental animal. In a previous paper it has been demonstrated that the permeability of the fish to water is affected both by ovine prolactin and by the concentration of calcium ions present in the medium (Potts & Fleming, 1970). Calcium ions have an effect on the ...

Regulation of the sodium permeability of the luminal membrane is the major mechanism by which the net rate of sodium transport across tight epithelia is varied. Previous evidence has suggested that the permeability of the luminal membrane might be regulated by changes in intracellular sodium or calcium activities. To test this directly, we isolated a fraction of the plasma membrane from the toa...

AB STR ACT The permeability of frog skin to a series of nonelectrolytes (thiourea, urea, mannitol, and sucrose) under the influence of 2.5 times normal osmolarity in the outer bathing solution has been investigated. Although the flux of the tracer nonelectrolytes across the skin in either direction is greatly increased by hyperosmolarity, the influx is found to be increased to a significantly g...

The permeability of frog skin to a series of nonelectrolytes (thiourea, urea, mannitol, and sucrose) under the influence of 2.5 times normal osmolarity in the outer bathing solution has been investigated. Although the flux of the tracer nonelectrolytes across the skin in either direction is greatly increased by hyperosmolarity, the influx is found to be increased to a significantly greater exte...

The European Renal Best Practice (ERBP) Advisory Board recently decided to follow up exisiting guidelines, and to publish position statements when new evidence would necessitate a change in the existing guideline 1 .The purpose of this document is to provide guidance on the interpretation and relevancy of the current European Best Practice Guideline on dialysis strategy 2 , in the light of the ...