15,470 research outputs found

    Monitoring atmospheric pollutants with a heterodyne radiometer transmitter-receiver

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    The presence of selected atmospheric pollutants can be determined by transmitting an infrared beam of proper wavelength through the atmosphere, and detecting the reflections of the transmitted beam with a heterodyne radiometer transmitter-receiver using part of the laser beam as a local oscillator. The particular pollutant and its absorption line strength to be measured are selected by the laser beam wave length. When the round-trip path for the light is known or measured, concentration can be determined. Since pressure (altitude) will affect the shape of the molecular absorption line of a pollutant, tuning the laser through a range of frequencies, which includes a part of the absorption line of the pollutant of interest, yields pollutant altitude data from which the altitude and altitude profile is determined

    A study of a development scheme in a Polynesian community : the citrus replanting scheme on Atiu, Cook Islands : a thesis presented in partial fulfilment of the requirements for the degree of Master of Arts in Geography at Massey University

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    Economic development is usually considered to be increasing levels of output per capita and in the past programmes aimed at improving economic conditions in undeveloped and underdeveloped nations have been formulated on this basic premise. However, recent experience has shown this to be a somewhat narrow definition, and economic development is increasingly being viewed as being but part of a broad process of social development involving basic changes in the underlying value systems of communities. Rising levels of output and income per capita show increases in productivity and wealth, but in many instances a prerequisite for attaining this or an outcome of it is change in social values. Therefore it is essential development be seen in its broadest context, as merely one element in the processes of social change and social evolution of man. Economic change cannot be divorced from other spheres of life as any alteration in this has ramifications elsewhere in the social system. Life in any culture is multidimensional in nature. The ability to perceive this is essential for development programmes in order that any social discordance and possible cultural lag associated with development be minimised. [From Preface

    Laser-excited fluorescence for measuring atmospheric pollution

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    System measures amount of given pollutant at specific location. Infrared laser aimed at location has wavelength that will cause molecules of pollutant to fluoresce. Detector separates fluorescence from other radiation and measures its intensity to indicate concentration of pollutant

    Weak Measurements with Entangled Probes

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    Encoding the imaginary part of a weak value onto an initially entangled probe can modify its entanglement content - provided the probe observable can distinguish between states of different entropies. Apart from fundamental interest, this result illustrates the utility of the imaginary weak value as a calculational tool in certain entanglement concentration protocols.Comment: 4 pages, single diagra

    Procrustean entanglement concentration of continuous variable states of light

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    We propose a Procrustean entanglement concentration scheme for continuous variable states inspired by the scheme proposed in Fiurasek et. al. Phys. Rev. A 67, 022304, (2003). We show that the eight-port homodyne measurement of Fiurasek et. al. Phys. Rev. A 67, 022304, (2003) can be replaced by a balanced homodyne measurement with the advantage of providing a success criterion that allows Alice and Bob to determine if entanglement concentration was achieved. In addition, it facilitates a straightforward and feasible experimental implementation.Comment: 6 pages, 3 figures; Typos corrected, References added and conclusion extended, Accepted for publication in Physical Review

    Blood lactate clearance during active recovery after an intense running bout depends on the intensity of the active recovery

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    High-intensity exercise training contributes to the production and accumulation of blood lactate, which is cleared by active recovery. However, there is no commonly agreed intensity or mode for clearing accumulated blood lactate. We studied clearance of accumulated blood lactate during recovery at various exercise intensities at or below the lactate threshold after high-intensity interval runs that prompted lactate accumulation. Ten males repeated 5-min running bouts at 90% of maximal oxygen uptake ([Vdot]O2max), which increased blood lactate concentration from 1.0 ± 0.1 to 3.9 ± 0.3 mmol · l-1. This was followed by recovery exercises ranging from 0 to 100% of lactate threshold. Repeated blood lactate measurements showed faster clearance of lactate during active versus passive recovery, and that the decrease in lactate was more rapid during higher (60-100% of lactate threshold) than lower (0-40% of lactate threshold) (P < 0.05) intensities. The more detailed curve and rate analyses showed that active recovery at 80-100% of lactate threshold had shorter time constants for 67% lactate clearance and higher peak clearance rates than 40% of lactate threshold or passive recovery (P < 0.05). Finally, examination of self-regulated intensities showed enhanced lactate clearance during higher versus lower intensities, further validating the intensity dependence of clearance of accumulated blood lactate. Therefore, active recovery after strenuous exercise clears accumulated blood lactate faster than passive recovery in an intensity-dependent manner. Maximum clearance occurred at active recovery close to the lactate threshold
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