Processing, storage and display of physiological measurements
ABSTRACT In the UK, standards of monitoring required for the safe management of anaesthesia are set by the Association of Anaesthetists of Great Britain and Ireland. In the past physiological measurements of, for example, blood pressure, electrocardiograph (ECG), gas composition and airway pressures may have been performed by a collection of individual electronic machines. It is now common however to have an integrated monitoring system where signals from a variety of transducers are amplified, filtered, converted to digital form, processed by a computer and presented on a display to inform the user of both the condition of the patient and function of the anaesthesia system. It is important to have some understanding of the processes that take place between the production of the raw analogue electrical signal by a transducer and the information that is finally presented to the user.
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ABSTRACT: The coastal landscapes in southwestern Korea include a diverse array of tidal wetlands and salt marshes. These coastal zones link the ecological functions of marine tidal wetlands and freshwater ecosystems with terrestrial ecosystems. They are rich in biological diversity and play important roles in sustaining ecological health and processing environmental pollutants. Korean tidal wetlands are particularly important as nurseries for economically important fishes and habitats for migratory birds. Diking, draining, tourism, and conversion to agricultural and urban uses have adversely affected Korean tidal wetlands. Recent large development projects have contributed to further losses. Environmental impact assessments conducted for projects affecting tidal wetlands and their surrounding landscapes should be customized for application to these special settings. Adequate environmental impact assessments will include classification of hydrogeomorphic units and consideration of their responses to biological and environmental stressors. As is true worldwide, Korean laws and regulations are changing to be more favorable to the conservation and protection of tidal wetlands. More public education needs to be done at the local level to build support for tidal wetland conservation. Some key public education points include the role of tidal wetlands in maintaining healthy fish populations and reducing impacts of nonpoint source pollution. There is also a need to develop procedures for integrating economic and environmental objectives within the overall context of sustainable management and land uses.Environmental Management 05/2010; 45(5):1014-26. · 1.65 Impact Factor
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ABSTRACT: Techniques for estimating the numbers of free-living algae on submerged sediments and soils are reviewed. A method that gives an estimate of the numbers of aIgae per unit area of habitat is described. Its r&ability is defined statistically, and optimum method designs are discussed. An adaptation of the procedure allows the pigment contents of the algal populations to be determined. The study of epipelic algae, which are de- fined as those fret-living on submerged sediments ( Round 1956)) has lagged be- hind studies of planktonic algae. There has been little progress in the development oE tcchniqucs for estimating epipelic popula- tion densities, and in a review of limnolog- ical methods, Lund and Talling (1957, p, 542) stated that "No accurate quantita- tive method of collecting algae living un- attached on the deposits has been de- vised," In this paper, the methods that have been used will first bc reviewed. These methods involve two stages, the collection of a representative and quantitative sample and the estimation of the number of algae in that sample. Round ( 19153) used a long glass tube stoppered by a finger at the upper end and with the lower end placed on the sur- face of the mud. By releasing the finger and simultaneously drawing the lower end of the tube across the mud surface, the tube fills with a mixture of surface material and overlying water. Reproducible results can be obtained, but the area sampled is not known, so results cannot be expressed on the basis of algae per unit area. Lund (1942) used an inverted funnel that lowered onto the mud. The surface materkd was sucked through a connecting tube into a collecting bottle under vacuum. The area and depth of sediment sampled cannot be determined accurately. Several workers, among them Brook ( 1954), used glass slides laid on the sub- stratum for various periods of time. I-Iow- eves, if the glass surfaces remain exposed to the water, epipelic algae may be sup- planted by attached forms, and if the sur- faces are covered by sediments, the cpipclic algae colonizing the sediment are easily washed off and lost when the slide is with- drawn from the water.Limnology and Oceanography - LIMNOL OCEANOGR. 01/1966; 11(4):584-595.
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ABSTRACT: On average, 5060 of diatomaceous opal produced in the euphotic zone redissolves within the upper 100 m of the water column. High specific silica dissolution rates in the surface ocean contrast with order-of-magnitude lower values in deep-sea sediments. The lack of a mechanistic understanding of these large variations in dissolution kinetics is a major source of uncertainty in models of nutrient silicon cycling in the oceans. Here we show that the observed variability in biogenic silica reactivity is consistent with results of experimental dissolution studies. Differences in aluminum content and specific surface area of the diatom skeletons, plus differences in temperature and degree of undersaturation, all contribute to lowering silica dissolution rates in deep-sea sediments relative to the euphotic zone. When variations in these material and environmental properties are accounted for, the predicted specific opal dissolution rate in average surface ocean water is over 2 orders of magnitude faster than the rate measured in recently deposited biosiliceous oozes of the Southern Ocean. The predicted specific dissolution rate, however, is approximately 5 times higher than the value obtained from global estimates of the depth-integrated dissolution rate and biogenic silica concentration in the upper water column. This discrepancy likely reflects the inhibitory effect of protective organic coatings on fresh diatom shells in surface waters. The experimental data further imply that aluminum incorporation in the silica matrix, during biomineralization or after death of the organisms, enhances the preservation efficiency of biogenic opal in marine sediments.Global Biogeochemical Cycles 01/2002; · 4.68 Impact Factor