10,918 research outputs found
A New Design Method for Vanadium Redox Batteries in Renewable Energy Systems
This study investigated the behavior of vanadium redox flow batteries (VRFBs), which are batteries capable of easily switching between charging and discharging modes, making them a suitable option for storing intermittent sources of alternative energies (solar, wind, etc). Since different sizes of the battery provide varying voltages, optimal parameters for a particular home are key for implementation. These parameters, specifically the cell and tank volumes of the battery that are capable of providing consistent on-load voltage, were determined using data from a 13 kW solar array and a medium-sized house. Charge/discharge current values were used to run a mathematical model that provided on-load voltage over time graphs based on parameter input values. Using this model, the optimal parameter values were found to be 11.5 L for the cell volume and 103.7 L for the tank volume, which maintenained the on-load voltage well above 0.80 V (10% of cell standard emf)
Targeting of anionic membrane species by lanthanide(III) complexes: towards improved MRI contrast agents for apoptosis
No abstract available
Investigating the Role of the Gut Microbiome in Huntington Disease
Huntington disease (HD) is an inherited neurodegenerative disease caused by a trinucleotide repeat expansion in the huntingtin (HTT) gene. Metabolic dysfunction is a feature of HD that is recapitulated in HD mouse models. Our lab has shown that circadian feeding rhythms are disrupted in humanized HD mice and restored by suppression of brain HTT. Furthermore, when circadian feeding rhythm is artificially restored, in addition to normalization of metabolic function, liver and striatal HTT is temporarily reduced, demonstrating that HTT is involved in gut-brain feedback. The gut microbiome, which can regulate gut-brain feedback, has been implicated in the pathogenesis of other central nervous system disorders and we hypothesize it also plays a role in HD. The objective of this study is to investigate alterations in relative abundance of HD gut microbiota using existing plasma metabolomics data to identify candidate bacteria. If distinct microbiota profiles are demonstrated, this would provide the basis for future unbiased studies to investigate the complete HD microbiome
Climbing the cosmic ladder with stellar twins
Distances to stars are key to revealing a three-dimensional view of the Milky
Way, yet their determination is a major challenge in astronomy. Whilst the
brightest nearby stars benefit from direct parallax measurements, fainter stars
are subject of indirect determinations with uncertainties exceeding 30%. We
present an alternative approach to measuring distances using
spectroscopically-identified twin stars. Given a star with known parallax, the
distance to its twin is assumed to be directly related to the difference in
their apparent magnitudes. We found 175 twin pairs from the ESO public HARPS
archives and report excellent agreement with Hipparcos parallaxes within 7.5%.
Most importantly, the accuracy of our results does not degrade with increasing
stellar distance. With the ongoing collection of high-resolution stellar
spectra, our method is well-suited to complement Gaia.Comment: published online on MNRA
Academic performance & student engagement in level 1 physics undergraduates
At the beginning of academic year 2007-08, staff in the Department of Physics
& Astronomy at the University of Glasgow started to implement a number of
substantial changes to the administration of the level 1 physics undergraduate
class. The main aims were to improve the academic performance and progression
statistics. With this in mind, a comprehensive system of learning support was
introduced, the main remit being the provision of an improved personal contact
and academic monitoring and support strategy for all students at level 1. The
effects of low engagement with compulsory continuous assessment components had
already been observed to have a significant effect for students sitting in the
middle of the grade curve. Analysis of data from the 2007-08 class showed that
even some nominally high-achieving students achieved lowered grades due to the
effects of low engagement. Nonetheless, academic and other support measures put
in place during 2007-08 played a part in raising the passrate for the level 1
physics class by approximately 8% as well as raising the progression rate by
approximately 10%.Comment: 12 pages, 3 figure
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