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Falls among inpatients usually arise from a complex combination of risk factors, including the effects of longstanding and acute illness, the ageing process and the side effects of medication, combined with the unfamiliar environment of a hospital. This article outlines the range of interventions that can reduce the likelihood of falls and injury, and explains the value of the Patient Safety First 'How to' guide in supporting nurses to implement them. Patient and service improvement case studies are described. [ABSTRACT FROM AUTHOR]

During competition for phosphate in continuous cultures, Cosmarium subcostatum Nord. routinely displaced Staurastrum paradoxum Meyer. The rate of displacement was independent of cell density between 100 and 6000 cells Ml[SUP-1]. This suggests that competition for nutrients is important over a wide range of naturally occurring cell densities. C. subcostatum had higher saturated rates of phosphate uptake but also higher half saturation values for uptake. As a result, the two desmids were similarly able to take up phosphate at low concentrations. The competitive advantage of C. subcostatum lay in its greater yield per unit of phosphorus. Growth of the two algae in shared medium in a dual-chamber chemostat had no effect on uptake or yield characteristics. [ABSTRACT FROM AUTHOR]

Focuses on the comparative pH dependent metal inhibition of nutrient uptake by Scenedesmus Quadricauda. Growth of the alga in chemostats with both nitrogen and phosphorus approaching limiting levels; Metal toxicity of the nitrate, ammonium and phosphate uptake systems of the algae in an identical physiological state.

The blue-green alga Synechococcus linearis (Naeg.) Kom, was grown in P- and N-limited chemostats over a range of potentially limiting irradiances in order to determine the combined effects of light and nutrient limitation on some aspects of the composition and metabolism of this alga. Over a narrow range of low irradiances, simultaneous limitation of growth rate by light and either N or P was shown. This simultaneous limitation of growth rate by a nutrient and a physical factor can be explained by the ability of an increased supply of one to compensate in part for a decreased supply of the other. At all irradiances, the internal concentration of the limiting nutrient increased with increasing dilution rate, and the results could be fitted to the Droop relationship. With decreasing irradiance, the internal concentration of the limiting nutrient increased. There appeared to be little or no effect of light on the minimum internal concentration of P but that of N increased with decreasing light, Both chlorophyll a and biliprotein per unit particulate C increased with increasing dilution rate and decreasing irradiance. The critical N/P ratio increased with decreasing light as the N requirement of N-limited cells increased faster than did the P requirement of P-limited cells. The composition of exponentially growing cells in complete medium varied much less with light. Neither dilution rate nor irradiance during growth had a great effect on saturated rates of P or N uptake or alkaline phosphatase activity. Calculated assimilation ratios increased with light and dilution rate. The role of the flexibility of nutrient composition in adaptation to adversa conditions and the implications of the results for the use of physiological indicators of nutrient status are discussed. [ABSTRACT FROM AUTHOR]

Changes in net photosynthesis, dark respiration, ATP content, and some other aspects of composition were measured following phosphate or ammonium additiono to cultures of the green alga Scenedesmus quadricauda (urp.) Bréb. deficient in phosphorus or nitrogen. The deficient nutrient was rapidly taken up. Light-saturated net photosynthesis was depressed below the pre-addition rate during nurtient uptake and did not increase markedly above that rate until several hours after uptake was complete. Dark respiration, on the other hand, was markedly stimulated during uptake of the deficient nutrient and to a lesser extent after uptake was complete. Phosphate addition to P-deficient cells caused a large increase in the ATP content within 2-4 h of addition, whereas ammonium addition to N-deficient cells caused much less or no increase in ATP content. Short-term enrichment experiments to detect nutrient limitations are evaluated in the light of these and similar results taken fromt he literature. The available evidence shows that photosynthetic responses cannot reliably be used in short-term enrichments but changes in respiration or ATP content may be useful in certain circumstances. [ABSTRACT FROM AUTHOR]

The response to arsenate in growth and phosphate uptake by five algae in culture varied considerably. The growth rates of Melosira granulata var. angustissima O Müll. And Ochromonas vallesiaca Chodat were depressed by 1 μM arsenate. Chlamydomonas reinhardtii Dang. Reguired 10μM for the same degree of depression, while the growth rates of Cryptomonas erosa Her. And Anabaena variabilias Kütz. Were unaffected up to 100 μM. however, following deplection of phosphate, cultures of the latter two algae began to ddie at the higher concentrations of arsenate tested. Growth of C. reinhardtii in the presence of 35 μM arsenate resulted in characteristics of P deficiency. Comparison of rates of photosynthesis, respiration, and phosphate uptake between cultures of C. reinhardtii which had grown in the presence and absence of arsenate showed little evidence after 16 doublings that it had adopted to arsenate. [ABSTRACT FROM AUTHOR]

Phosphorus-limited chemostats were used to study the effect of degree of phosphorus deficiency on several aspects of the composition and metabolism of Anabaena variabilis Kütz. and Scenedesmus quadricauda (Turp.) Bréb. The changes as a function of the dilution rate could be placed into 3 patterns. Most aspects of the composition showed a progressive change with dilution rate. The carbohydrate content generally increased while cellular P and nitrogen, protein, nucleic acid and chlorophyll contents generally decreased over the entire range of increasing deficiency studied. The changes in metabolism fell into a second pattern, showing great sensitivity to the onset of P deficiency. The ability to take up phosphate and the alkaline phosphatase activity increased most markedly with increasing deficiency at the higher dilution rates. The third pattern was confined to the lipid content of S. quadricauda, which increased with deficiency only at the lowest dilution rates. [ABSTRACT FROM AUTHOR]

Several aspects of the metabolism and composition of a strain of Anabaena have been studied during phosphorus deficiency. The effects of medium composition, substrate concentration, temperature, pH, and illumination on alkaline phosphatase activity and phosphate uptake have been examined. Of particular interest among these results was the dependence of maximum alkaline phosphatase activity on Ca and of phosphate uptake on Mg. Depletion of dissolved phosphate from the culture medium was accompanied by et marked increase in alkaline phosphatase activity, initial rate of phosphate uptake, and total amount of phosphate taken up to satisfaction of the phosphorus debt. Readdition of phosphate to a phosphorus-deficient culture resulted in a rapid decline in the ability to the up phosphate but no loss of alkaline phosphatase beyond dilution of activity already present. Entry into phosphorus deficiency was accompanied by loss of beterocysts, a decline in chlorophyll a, protein, RNA, and cellular phosphorus, and an increase in carbohydrate per unit dry weight. The possible use of these changes as physiological indicators of phosphorus limitation in natural situaliions is discussed. [ABSTRACT FROM AUTHOR]

Apparently by analogy with enzyme kinetics, the half-saturation value (K) for nutrient uptake or growth has frequently been overemphasized in discussions of competition, and the role of maximum rates (R) has not been given sufficient emphasis. The ratio R/K, which is the slope of the Monod equation at lowest substrate concentration, offers a simple way of emphasizing both factors. Several examples from the literature are cited to show that this ratio better reflects rates at lowest concentrations, and therefore competitive position in the process being considered, than do K values alone. [ABSTRACT FROM AUTHOR]

The carotenoids of 4 species of blue-green algae, Anabaena variabilis, Phormiditun persicinum, P. ectocarpi, and P. fragile, were investigated. In each, β-carotene was a major pigment and the only carotene detected. The xanthophylls present in Anabaena variabilis were echinenone, canthaxanthin, and myxoxanthopbyll. Each of the Phormidium species contained zeaxanthin as the major xanthophyll. In each, this was accompanied by trace amounts of echinenone and isocryptoxanthin. In addition, 2 new xanthophylls, spectrally resembling β-carotene, were found in Phormidium persicinum and P. ectocarpi, while another, with a spectrum similar to that of myxoxanthophyll, was found in P. fragile. [ABSTRACT FROM AUTHOR]