1,374 research outputs found
3D electron density distributions in the solar corona during solar minima: assessment for more realistic solar wind modeling
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
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
Parents’ experiences of using labelling information when making breakfast cereal choices for their children
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
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Minimal breast milk transfer of rituximab, a monoclonal antibody used in neurological conditions.
ObjectiveTo determine the transfer of rituximab, an anti-CD20 monoclonal antibody widely used for neurologic conditions, into mature breast milk.MethodsBreast milk samples were collected from 9 women with MS who received rituximab 500 or 1,000 mg intravenous once or twice while breastfeeding from November 2017 to April 2019. Serial breast milk samples were collected before infusion and at 8 hours, 24 hours, 7 days, and 18-21 days after rituximab infusion in 4 patients. Five additional patients provided 1-2 samples at various times after rituximab infusion.ResultsThe median average rituximab concentration in mature breast milk was low at 0.063 μg/mL (range 0.046-0.097) in the 4 patients with serial breast milk collection, with an estimated median absolute infant dose of 0.0094 mg/kg/d and a relative infant dose (RID) of 0.08% (range 0.06%-0.10%). Most patients had a maximum concentration at 1-7 days after infusion. The maximum concentration occurred in a woman with a single breast milk sample and was 0.29 μg/mL at 11 days postinfusion, which corresponds with an estimated RID of 0.33%. Rituximab concentration in milk was virtually undetectable by 90 days postinfusion.ConclusionsWe determined minimal transfer of rituximab into mature breast milk. The RID for rituximab was less than 0.4% and well below theoretically acceptable levels of less than 10%. Low oral bioavailability would probably also limit the absorption of rituximab by the newborn. In women with serious autoimmune neurologic conditions, monoclonal antibody therapy may afford an acceptable benefit to risk ratio, supporting both maternal treatment and breastfeeding
Improving health and education outcomes for children in remote communities: A cross-sector and developmental evaluation approach
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
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
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
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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