33 research outputs found

    Prospective organisation of neonatal arm movements : a motor foundation of embodied agency, disrupted in premature birth

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    Prospective motor control moves the body into the future, from where one is to where one wants to be. It is a hallmark of intentionality. But its origins in development is uncertain. In this study, we tested whether or not the arm movements of newborn infants were prospectively controlled. We measured the spatiotemporal organisation of 480 neonatal arm movements and 384 arm movements of infants prematurely born at-risk for neurodevelopmental disorder. We found 75% of healthy term-birth neonatal movements and 68% of prematurely-born infant movements conformed to the tauG-coupling model of prospective sensorimotor control. Prospective coupling values were significantly reduced in the latter (p = .010, r = .087). In both cases prospectively controlled movements were tightly organised by fixed-duration units with a base duration of 218 ms and additional temporal units of 145 ms. Yet distances remained constant. Thus, we demonstrate for the first time a precise prospective spatiotemporal organisation of neonatal arm movements and demonstrate at-risk infants exhibit reduced sensorimotor control. Prospective motor control is a hallmark of primary sensorimotor intentionality and gives a strong embodied foundation to conscious motor agency

    The Scientific Foundations of Forecasting Magnetospheric Space Weather

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    The magnetosphere is the lens through which solar space weather phenomena are focused and directed towards the Earth. In particular, the non-linear interaction of the solar wind with the Earth's magnetic field leads to the formation of highly inhomogenous electrical currents in the ionosphere which can ultimately result in damage to and problems with the operation of power distribution networks. Since electric power is the fundamental cornerstone of modern life, the interruption of power is the primary pathway by which space weather has impact on human activity and technology. Consequently, in the context of space weather, it is the ability to predict geomagnetic activity that is of key importance. This is usually stated in terms of geomagnetic storms, but we argue that in fact it is the substorm phenomenon which contains the crucial physics, and therefore prediction of substorm occurrence, severity and duration, either within the context of a longer-lasting geomagnetic storm, but potentially also as an isolated event, is of critical importance. Here we review the physics of the magnetosphere in the frame of space weather forecasting, focusing on recent results, current understanding, and an assessment of probable future developments.Peer reviewe

    Radio observations of the merging galaxy cluster system Abell 3391-Abell 3395

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    The pre-merging system of galaxy clusters Abell 3391-Abell 3395 located at a mean redshift of 0.053 has been observed at 1 GHz in an ASKAP/EMU Early Science observation as well as in X-rays with eROSITA. The projected separation of the X-ray peaks of the two clusters is 50\u2032 or 3.1 Mpc. Here we present an inventory of interesting radio sources in this field around this cluster merger. While the eROSITA observations provide clear indications of a bridge of thermal gas between the clusters, neither ASKAP nor MWA observations show any diffuse radio emission coinciding with the X-ray bridge. We derive an upper limit on the radio emissivity in the bridge region of (J)1 GHz < 1.2 7 10-44 W Hz-1 m-3. A non-detection of diffuse radio emission in the X-ray bridge between these two clusters has implications for particle-Acceleration mechanisms in cosmological large-scale structure. We also report extended or otherwise noteworthy radio sources in the 30 deg2 field around Abell 3391-Abell 3395. We identified 20 Giant Radio Galaxies, plus 7 candidates, with linear projected sizes greater than 1 Mpc. The sky density of field radio galaxies with largest linear sizes of >0.7 Mpc is 481.7 deg-2, three times higher than previously reported. We find no evidence for a cosmological evolution of the population of Giant Radio Galaxies. Moreover, we find seven candidates for cluster radio relics and radio halos
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