1,020 research outputs found

    Morning quiet-time ionospheric current reversal at mid to high latitudes

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    The records of an array of magnetometers set up across the Australian mainland are examined. In addition to a well-defined current whorl corresponding to the ionospheric <i>S<sub>q</sub></i> current system, another system of eastward flowing currents is often found in the early morning. The system is most easily identified at observatories poleward of the focus of the <i>S<sub>q</sub></i> system, where a morning reversal from eastward to westward currents can be seen. The time of the reversal is usually later, sometimes up to 12h local noon, in June (Southern Winter) than in other seasons. There is some evidence of a similar current system at other longitudes and in the Northern Hemisphere. An important outcome of the study is that it enables identification of which features of a daily variation of the northward magnetic field Δ<i>X</i> relate to an <i>S<sub>q</sub></i> current whorl and which must be attributed to some other current system

    Reduced kidney function in living kidney donors

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    Anesthesia for thoracic surgery in infants and children

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    The management of infants and children presenting for thoracic surgery poses a variety of challenges for anesthesiologists. A thorough understanding of the implications of developmental changes in cardiopulmonary anatomy and physiology, associated comorbid conditions, and the proposed surgical intervention is essential in order to provide safe and effective clinical care. This narrative review discusses the perioperative anesthetic management of pediatric patients undergoing noncardiac thoracic surgery, beginning with the preoperative assessment. The considerations for the implementation and management of one-lung ventilation (OLV) will be reviewed, and as will the anesthetic implications of different surgical procedures including bronchoscopy, mediastinoscopy, thoracotomy, and thoracoscopy. We will also discuss pediatric-specific disease processes presenting in neonates, infants, and children, with an emphasis on those with unique impact on anesthetic management

    Analytical models for Cross-correlation signal in Time-Distance Helioseismology

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    In time-distance helioseismology, the time signals (Doppler shifts) at two points on the solar surface, separated by a fixed angular distance are cross-correlated, and this leads to a wave packet signal. Accurately measuring the travel times of these wave packets is crucial for inferring the sub-surface properties in the Sun. The observed signal is quite noisy, and to improve the signal-to-noise ratio and make the cross-correlation more robust, the temporal oscillation signal is phase-speed filtered at the two points in order to select waves that travel a fixed horizontal distance. Hence a new formula to estimate the travel times is derived, in the presence of a phase speed filter, and it includes both the radial and horizontal component of the oscillation displacement signal. It generalizes the previously used Gabor wavelet that was derived without a phase speed filter and included only the radial component of the displacement. This is important since it will be consistent with the observed cross-correlation that is computed using a phase speed filter, and also it accounts for both the components of the displacement. The new formula depends on the location of the two points on the solar surface that are being cross correlated and accounts for the travel time shifts at different locations on the solar surface.Comment: 27 pages, 8 figures, ApJ in pres

    Adam Smith and Colonialism

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    In the context of debates about liberalism and colonialism, the arguments of Adam Smith have been taken as illustrative of an important line of anti-colonial liberal thought. The reading of Smith presented here challenges this interpretation. It argues that Smith’s opposition to colonial rule derived largely from its impact on the metropole, rather than on its impact on the conquered and colonised; that Smith recognised colonialism had brought ‘improvement’ in conquered territories and that Smith struggled to balance recognition of moral diversity with a universal moral framework and a commitment to a particular interpretation of progress through history. These arguments have a wider significance as they point towards some of the issues at stake in liberal anti-colonial arguments more generally
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