1,323 research outputs found

    3D electron density distributions in the solar corona during solar minima: assessment for more realistic solar wind modeling

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    Knowledge of the electron density distribution in the solar corona put constraints on the magnetic field configurations for coronal modeling and on initial conditions for solar wind modeling. We work with polarized SOHO/LASCO-C2 images from the last two recent minima of solar activity (1996-1997 and 2008-2010), devoid of coronal mass ejections. The goals are to derive the 4D electron density distributions in the corona by applying a newly developed time-dependent tomographic reconstruction method and to compare the results between the two solar minima and with two magnetohydrodynamic models. First, we confirm that the values of the density distribution in thermodynamic models are more realistic than in polytropic ones. The tomography provides more accurate distributions in the polar regions, and we find that the density in tomographic and thermodynamic solutions varies with the solar cycle in both polar and equatorial regions. Second, we find that the highest-density structures do not always correspond to the predicted large-scale heliospheric current sheet or its helmet streamer but can follow the locations of pseudo-streamers. We deduce that tomography offers reliable density distributions in the corona, reproducing the slow time evolution of coronal structures, without prior knowledge of the coronal magnetic field over a full rotation. Finally, we suggest that the highest-density structures show a differential rotation well above the surface depending on how they are magnetically connected to the surface. Such valuable information on the rotation of large-scale structures could help to connect the sources of the solar wind to their in situ counterparts in future missions such as Solar Orbiter and Solar Probe Plus.Comment: 23 pages, 9 figure

    The Effect of a Square-Stepping Exercise Intervention on Heart Rate Variability in Older Individuals with Type 2 Diabetes and Subjective Cognitive Complaints

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    Aging is associated with increased onset of diseases such as type 2 diabetes (T2D) and cognitive impairment. Heart rate variability (HRV), a measure of autonomic function, is reduced in T2D and may have the potential to indicate cognitive decline in this population. Square-stepping exercise (SSE) is a novel cognitive exercise recently implemented in cognitive research, which may have the potential to improve global cognitive function in T2D individuals. Participants with T2D (N=25, aged ≥ 50y) and self-reported cognitive complaints were randomized into either an SSE intervention or a wait-list (WL) control group for 24-weeks. HRV parameters (time and frequency domain) and GCF domains were assessed at baseline and 24-weeks. No significant differences were found in HRV parameters between groups at baseline and 24-weeks. However, heart rate was significantly reduced from baseline to 24-weeks in the SSE group, p = 0.046. Additionally, low and high frequency power were significantly decreased from baseline to 24-weeks in the WL group, p = 0.05 and p = 0.043 respectively. This study elucidates the impact of cognitive exercise training on HRV, however, it is inconclusive as to why a shift towards vagal modulation was observed in both the SSE and WL groups

    Claire Bronson \u2769-Kathryn Riley \u2769

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    Parents’ experiences of using labelling information when making breakfast cereal choices for their children

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    The consequences of a poor quality diet are slow to develop and easy to ignore, however, the impact on the health of communities as a whole is great (Lean, 2015). With the current upward trend in obesity, especially in children, this review looks into a variety of food labelling systems in order to determine their influence on consumers’ eating habits. The food labelling systems currently in place are only partially effective, with some seeming to demonstrate complete operational failure, therefore more research is needed in order to understand the cognitive processes used by consumers when making decisions using food labels. As a commonly consumed product which varies widely in nutritional content, and displays an array of different types of labelling information, breakfast cereal could benefit from further research into how the different food labelling systems are used and understood by consumers.Fallows, Stephe

    Articulāte Vol. XXVII

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    Improving health and education outcomes for children in remote communities: A cross-sector and developmental evaluation approach

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    Early childhood is one of the most influential developmental life stages. Attainments at this stage will have implications for the quality of life children experience as they transition to adulthood. Children residing in remote Australia are exposed to socioeconomic disadvantage that can contribute to developmental delays and resultant poorer education and health outcomes. Complex contributing factors in far west New South Wales have resulted in children with speech and fine motor skill delays experiencing no to limited access to allied health services for a number of decades. More recently, growing awareness that no single policy, government agency, or program could effectively respond to these complexities or ensure appropriate allied health service access for children in these communities has led to the development of the Allied Health in Outback Schools Program, which has been operational since 2009. The program is underpinned by cross-sector partnerships and a shared aspirational aim to improve the developmental outcomes of children to enhance their later life opportunities. It was identified early that the initiative had the potential to deliver mutually beneficial outcomes for communities and participating partner organisations.Over the last five years the program has been the catalyst for partnership consolidation, expansion and diversification. The developmental evaluation approach to continuous program adaptation and refinement has provided valuable insights that have informed health and education policy and enabled the program to be responsive to changing community needs, emerging policy and funding reforms.This article explores the evolution of the program partnerships, their contribution to program success and longevity, and their capacity to respond to an emergent and dynamic environment. The authors propose that a community-centred and developmental approach to program innovation and implementation in remote locations is required. This is based on the premise that contemporary linear, logic-based policy development and funding allocations, with predetermined program deliverables and outcomes, are no longer capable of responding appropriately to the complexities experienced by remote communities.Keywords: allied health, remote communities, cross-sectoral partnerships, service learnin

    The impact of streetlights on an aquatic invasive species: artificial light at night alters signal crayfish behaviour

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    Artificial light at night (ALAN) can significantly alter the behaviour, communication and orientation of animals, and will potentially interact with other stressors to affect biodiversity. Invasive, non-native species are one of the largest threats to freshwater biodiversity; however, the impact of ALAN on such species is unknown. This study assessed the effects of ALAN at ecologically relevant levels on the behaviour of a globally widespread invasive species, the signal crayfish (Pacifastacus leniusculus). In experimental aquaria, crayfish were exposed to periods of daylight, control (<0.1 lx) and street-lit nights to test two hypotheses: (1) signal crayfish under natural conditions are nocturnal animals, spending more time in shelter during the day, whilst active and interacting during the night, and (2) ALAN reduces crayfish activity and intraspecific interactions, whilst increasing their propensity to use shelter. Our results confirm that signal crayfish are largely nocturnal, showing peak activity and interaction levels during control nights, whilst taking refuge during daylight hours. When exposed to short-term simulated light pollution from a streetlight at night however, activity and interactions with conspecifics were significantly reduced compared to control nights, whilst time spent in shelters increased. By altering crayfish behaviour, ALAN may change the ecosystem impacts of invasive crayfish in the wild. This study is the first to show an impact of ALAN on the behaviour of an invasive, non-native species, and provides information for the management of invasive crayfish in areas where ALAN is prevalent

    Real-time in vivo optogenetic neuromodulation and multielectrode electrophysiologic recording with NeuroRighter

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    Optogenetic channels have greatly expanded neuroscience’s experimental capabilities, enabling precise genetic targeting and manipulation of neuron subpopulations in awake and behaving animals. However, many barriers to entry remain for this technology – including low-cost and effective hardware for combined optical stimulation and electrophysiologic recording. To address this, we adapted the open-source NeuroRighter multichannel electrophysiology platform for use in awake and behaving rodents in both open and closed-loop stimulation experiments. Here, we present these cost-effective adaptations, including commercially available LED light sources; custom-made optical ferrules; 3D printed ferrule hardware and software to calibrate and standardize output intensity; and modifications to commercially available electrode arrays enabling stimulation proximally and distally to the recording target. We then demonstrate the capabilities and versatility of these adaptations in several open and closed-loop experiments, demonstrate spectrographic methods of analyzing the results, as well as discuss artifacts of stimulation.Emory University. School of Medicine (Emory Neurosciences Initiative seed grant)American Epilepsy SocietyEpilepsy Foundation of America (Predoctoral fellowship)National Science Foundation (U.S.) (NSF GRFP Fellowship 08-593)National Science Foundation (U.S.) (NSF IGERT Fellowship DGE-0333411)National Science Foundation (U.S.) (NSF EFRI #1238097)National Institutes of Health (U.S.) (NIH 1R01NS079757-01)American Society for Engineering Education (SMART Fellowship

    Acute Demyelinating Disease after Oral Therapy with Herbal Extracts

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    Central nervous system demyelinating processes such as multiple sclerosis and acute disseminated encephalomyelitis constitute a group of diseases not completely understood in their physiopathology. Environmental and toxic insults are thought to play a role in priming autoimmunity. The aim of the present report is to describe a case of acute demyelinating disease with fatal outcome occurring 15 days after oral exposure to herbal extracts
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