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Different Principles (different + principle)
Selected AbstractsRelationship between the isotopically exchangeable and resin-extractable phosphate of deficient to heavily fertilized soilEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 4 2000A. Schneider Summary The rate and extent of soil,solution transfer of orthophosphate ions (Pi) depend both on soil solution Pi concentration and on time. This is so both in experiments on sorption,desorption and in those on isotopic exchange. Because the two methods are based on different principles, it is questionable whether they give a similar quantification of Pi transfer. The amount of isotopically exchangeable Pi, E, was determined over periods of 100 minutes and described as a function of both time and Pi concentration in solution for three soil samples taken from field plots having different P fertilizer histories over 26 years of annual application. In separate experiments, amounts of Pi, Qd, were extracted from soil suspensions using three levels of anion exchange resin strips for periods ranging from 10 minutes to 7 days. Both initial and final solution Pi concentrations were measured. These concentrations and periods of resin-contact were used to predict the difference in E, ,E, between the initial and final states of the suspension,resin system using extrapolations of the equations fitted to the exchange data. Under conditions in which the solution concentration of Pi decreased during extraction the ,E values and the resin-extracted Pi values, Qd, were equal. It is thus possible, using the description of E, to predict the amount of Pi released from soil suspension knowing the initial and final solution Pi concentrations and the time it took for the system to pass from the initial to the final state. For the soil studied, identical amounts of mobile Pi, i.e. the Pi which participates in the soil,solution dynamics, may therefore be assessed by either isotopic exchange or desorption. [source] Social participation in health in Brazil and England: inclusion, representation and authorityHEALTH EXPECTATIONS, Issue 3 2009Marian Barnes BA MA PhD Abstract Aim, This article offers a brief description and analysis of public participation in health in Brazil and England in order to highlight different motivators and tensions within an acceptance of participation as official policy. Sources/methods, The article draws on a range of research in both countries and an analysis of official documents relating to participation. It is based on collaboration between researchers deriving from broad programmes of work on public participation in which the authors are involved. Argument, There is a tension between different principles underpinning collective public involvement in health both within and between countries. Different aspirations or claims have been made about what such participation will achieve and there are trade-offs between design principles that have consequences for issues such as who takes part and thus also for what can be achieved. The democratic origins of public participation are more evident in the Brazilian situation than in England, but there are still questions about the inclusivity of the practices through which this is achieved. The English picture is both more diverse and dynamic, but formal decision-making power of participatory forums is less than in Brazil. Whilst social justice claims for participation have been made in both countries, there is as yet limited evidence that these have been realized. [source] Detection of volatile organic compounds using a polythiophene derivativePHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 7 2010V. C. Gonçalves Abstract Conjugated polymers have been subject of great interest in the recent literature from both fundamental point of view and applied science perspective. Among the several types of conjugated polymers used in recent investigations, polythiophene and its derivatives have attracted considerable attention over the past 20,years due to their high mobility and other remarkable solid-state properties. They have potential applications in many fields, such as microelectronic devices, catalysts, organic field-effect transistors, chemical sensors, and biosensors. They have been studied as gas and volatile organic compounds (VOCs) sensors using different principles or transduction techniques, such as optical absorption, conductivity, and capacitance measurements. In this work, we report on the fabrication of gas sensors based on a conducting polymer on an interdigitated gold electrode. We use as active layer of the sensor a polythiophene derivative: poly (3-hexylthiophene) (P3HT) and analyzed its conductivity as response for exposure to dynamic flow of saturated vapors of six VOCs [n -hexane, toluene, chloroform, dichloromethane, methanol, and tetrahydrofuran (THF)]. Different responses were obtained upon exposure to all VOCs, THF gave the higher response while methanol the lower response. The influence of moisture on the measurements was also evaluated. [source] The 3-Minute Emergency Medicine Medical Student Presentation: A Variation on a ThemeACADEMIC EMERGENCY MEDICINE, Issue 7 2008Chip Davenport BA Abstract Oral presentations are a critical element in the communication of medical knowledge between students and faculty, but in most locations, the amount of time spent on teaching the oral presentation is minimal. Furthermore, the standard oral presentation does not work well within the emergency medicine (EM) setting, due to time constraints and the different principles that make EM a unique specialty. This article provides a suggested approach on how to educate students on optimal oral presentations in EM, as well as providing a link to an online guide instructing medical students how to give oral presentations. [source] Comparability of three-dimensional optic disc imaging with different techniquesACTA OPHTHALMOLOGICA, Issue 1 2000A study with confocal scanning laser tomography, raster tomography ABSTRACT. Purpose: We wanted to compare optic nerve head topography measurements and discrimination between normal and glaucomatous eyes with two entirely different three-dimensional optic disc imaging techniques, confocal scanning laser tomography (Heidelberg Retina Tomograph, Heidelberg Engineering) and raster tomography (Glaucoma-Scope, Ophthalmic Imaging Systems). Methods: Both eyes of 225 normal subjects and 229 eyes of 166 patients with glaucoma at different stages were imaged with the Heidelberg Retina Tomograph and the Glaucoma-Scope. Optics discs were analysed in 15° sectors around the circumference. Depth measurements were calibrated on objects with known dimensions. Results: We observed no significant differences in absolute measurements of maximum cup depth and cup area between the two instruments. We observed small differences in absolute measurements of disc anti rim area between the two instruments. Discrimination between normal and glaucomatous eyes was close to identical for the two instruments. Both instruments had the same ability to distinguish glaucomatous regional alterations of optic nerve head topography from normal disc configuration. Conclusion: Both instruments while using entirely different principles for three-dimensional optic disc imaging gave very similar results. This correspondence of results implies that the same optic disc parameters can be analysed, and the results interpreted similarly for both methods, and probably with other three-dimensional imaging instruments. It may also indicate that results of studies with one of the instruments have general validity. [source] | ||||||||||