728 research outputs found
The linear tearing instability in three dimensional, toroidal gyrokinetic simulations
Linear gyro-kinetic simulations of the classical tearing mode in
three-dimensional toroidal geometry were performed using the global gyro
kinetic turbulence code, GKW . The results were benchmarked against a
cylindrical ideal MHD and analytical theory calculations. The stability, growth
rate and frequency of the mode were investigated by varying the current
profile, collisionality and the pressure gradients. Both collision-less and
semi-collisional tearing modes were found with a smooth transition between the
two. A residual, finite, rotation frequency of the mode even in the absense of
a pressure gradient is observed which is attributed to toroidal finite
Larmor-radius effects. When a pressure gradient is present at low
collisionality, the mode rotates at the expected electron diamagnetic
frequency. However the island rotation reverses direction at high
collisionality. The growth rate is found to follow a scaling with
collisional resistivity in the semi-collisional regime, closely following the
semi-collisional scaling found by Fitzpatrick. The stability of the mode
closely follows the stability using resistive MHD theory, however a
modification due to toroidal coupling and pressure effects is seen
Relative Impact of Highway Construction on Wetland Hydrology in Environmentally Sensitive Areas in Southeast Louisiana
Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv
Reducing the susceptibility of lumped-element KIDs to two-level system effects
Arrays of lumped-element kinetic inductance detectors (LEKIDs) optically
coupled through an antenna-coupled transmission line are a promising candidate
for future cosmic microwave background (CMB) experiments. However, the
dielectric materials used for the microstrip architecture are known to degrade
the performance of superconducting resonators. In this paper, we investigate
the feasibility of microstrip coupling to a LEKID, focusing on a systematic
study of the effect of depositing amorphous silicon-nitride on a LEKID. The
discrete and spatially-separated inductive and capacitive regions of the LEKID
allow us to vary the degree of dielectric coverage and determine the
limitations of the microstrip coupling architecture. We show that by careful
removal of dielectric from regions of high electric field in the capacitor,
there is minimal degradation in dielectric loss tangent of a partially covered
lumped-element resonator. We present the effects on the resonant frequency and
noise power spectral density and, using the dark responsivity, provide an
estimate for the resulting detector sensitivity.Comment: Presented at the 18th International Workshop on Low Temperature
Detectors. Published in the Journal of Low Temperature Physic
Original paper Cell free DNA as a marker of training status in weightlifters
The purpose of this investigation was to elucidate the changes in cf-DNA as it relates to fluctuations in resistance training workloads and intensities. The relationship between cell free DNA (cf-DNA), C-reactive protein (CRP), creatine kinase (CK), testosterone (T), cortisol (C), testosterone-cortisol ratio (T:C), body mass and body composition were also examined. Eight weightlifters (5 males and 3 females, age = 25 ± 3.5 yr, body mass = 88.3 ± 22.7 kg, height = 173.8 ±8.4 cm) volunteered to participate in this study. Venous blood samples, body mass and body composition were taken six times, each corresponding to the end of a training phase. CK (p = 0.018, η² = 0.409) and CK %Δ (p \u3c 0.001, η² = 0.594) were the only biochemical variables to reach statistical significance at any point. A number of statistically significant correlations were found among variables. VLD4wk was related to CK %Δ (r = 0.86), VLD4wk %Δ was related CK %Δ (r = 0.86) and TID1wk was related to CRP (r = 0.83). cf-DNA %Δ was correlated with CRP and CRP %Δ (r = 0.83 and 0.86, respectively). CRP and CRP %Δ were correlated with BF % (r = 0.94 and 0.92, respectively). CK and CK %Δ were both related to T:C (r = 0.94 and 0.89, respectively) and T:C %Δ (r = 0.87 and 0.86, respectively). The correlation between cf-DNA and CRP suggests that cf-DNA may be a valuable indicator of inflammation in weightlifters
Cell Free Dna As A Marker Of Training Status In Weightlifters
The purpose of this investigation was to elucidate the changes in cf-DNA as it relates to fluctuations in resistance training workloads and intensities. The relationship between cell free DNA (cf-DNA), C-reactive protein (CRP), creatine kinase (CK), testosterone (T), cortisol (C), testosterone-cortisol ratio (T:C), body mass and body composition were also examined. Eight weightlifters (5 males and 3 females, age = 25 ± 3.5 yr, body mass = 88.3 ± 22.7 kg, height = 173.8 ±8.4 cm) volunteered to participate in this study. Venous blood samples, body mass and body composition were taken six times, each corresponding to the end of a training phase. CK (p = 0.018, η² = 0.409) and CK %Δ (p \u3c 0.001, η² = 0.594) were the only biochemical variables to reach statistical significance at any point. A number of statistically significant correlations were found among variables. VLD4wk was related to CK %Δ (r = 0.86), VLD4wk %Δ was related CK %Δ (r = 0.86) and TID1wk was related to CRP (r = 0.83). cf-DNA %Δ was correlated with CRP and CRP %Δ (r = 0.83 and 0.86, respectively). CRP and CRP %Δ were correlated with BF % (r = 0.94 and 0.92, respectively). CK and CK %Δ were both related to T:C (r = 0.94 and 0.89, respectively) and T:C %Δ (r = 0.87 and 0.86, respectively). The correlation between cf-DNA and CRP suggests that cf-DNA may be a valuable indicator of inflammation in weightlifters
Cell Free DNA as a Marker of Training Status in Weightlifters
The purpose of this investigation was to elucidate the changes in cf-DNA as it relates to fluctuations in resistance training workloads and intensities. The relationship between cell free DNA (cf-DNA), C-reactive protein (CRP), creatine kinase (CK), testosterone (T), cortisol (C), testosterone-cortisol ratio (T:C), body mass and body composition were also examined. Eight weightlifters (5 males and 3 females, age = 25 ± 3.5 yr, body mass = 88.3 ± 22.7 kg, height = 173.8 ±8.4 cm) volunteered to participate in this study. Venous blood samples, body mass and body composition were taken six times, each corresponding to the end of a training phase. CK (p = 0.018, η² = 0.409) and CK %Δ (p \u3c 0.001, η² = 0.594) were the only biochemical variables to reach statistical significance at any point. A number of statistically significant correlations were found among variables. VLD4wk was related to CK %Δ (r = 0.86), VLD4wk %Δ was related CK %Δ (r = 0.86) and TID1wk was related to CRP (r = 0.83). cf-DNA %Δ was correlated with CRP and CRP %Δ (r = 0.83 and 0.86, respectively). CRP and CRP %Δ were correlated with BF % (r = 0.94 and 0.92, respectively). CK and CK %Δ were both related to T:C (r = 0.94 and 0.89, respectively) and T:C %Δ (r = 0.87 and 0.86, respectively). The correlation between cf-DNA and CRP suggests that cf-DNA may be a valuable indicator of inflammation in weightlifters
Design and performance of the antenna coupled lumped-element kinetic inductance detector
Focal plane arrays consisting of low-noise, polarisation-sensitive detectors
have made possible the pioneering advances in the study of the cosmic microwave
background (CMB). To make further progress, the next generation of CMB
experiments (e.g. CMB-S4) will require a substantial increase in the number of
detectors compared to the current stage 3 instruments. Arrays of kinetic
inductance detectors (KIDs) provide a possible path to realising such large
format arrays owing to their intrinsic multiplexing advantage and relative
cryogenic simplicity. In this proceedings, we report on the design of a novel
variant of the traditional KID design; the antenna-coupled lumped-element KID.
A polarisation sensitive twin-slot antenna placed behind an optimised
hemispherical lens couples power onto a thin-film superconducting microstrip
line. The power is then guided into the inductive section of an aluminium KID
where it is absorbed and modifies both the resonant frequency and quality
factor of the KID. We present the various aspects of the design and preliminary
results from the first set of seven-element prototype arrays and compare to the
expected modelled performance
The orexigenic hormone acyl-ghrelin increases adult hippocampal neurogenesis and enhances pattern separation.
An important link exists between intact metabolic processes and normal cognitive functioning; however, the underlying mechanisms remain unknown. There is accumulating evidence that the gut hormone ghrelin, an orexigenic peptide that is elevated during calorie restriction (CR) and known primarily for stimulating growth hormone release, has important extra-hypothalamic functions, such as enhancing synaptic plasticity and hippocampal neurogenesis. The present study was designed to evaluate the long-term effects of elevating acyl-ghrelin levels, albeit within the physiological range, on the number of new adult born neurons in the dentate gyrus (DG) and performance on the Spontaneous Location Recognition (SLR) task, previously shown to be DG-dependent and sensitive to manipulations of plasticity mechanisms and cell proliferation. The results revealed that peripheral treatment of rats with acyl-ghrelin enhanced both adult hippocampal neurogenesis and performance on SLR when measured 8-10 days after the end of acyl-ghrelin treatment. Our data show that systemic administration of physiological levels of acyl-ghrelin can produce long-lasting improvements in spatial memory that persist following the end of treatment. As ghrelin is potentially involved in regulating the relationship between metabolic and cognitive dysfunction in ageing and neurodegenerative disease, elucidating the underlying mechanisms holds promise for identifying novel therapeutic targets and modifiable lifestyle factors that may have beneficial effects on the brain.This work was supported by grants from the Medical Research Council (grant
G0902250/94306), The Royal Society and the Biotechnology and Biological
Sciences Research Council (grant BB/G019002/1).This is the final version. It was first published by Elsevier at http://www.sciencedirect.com/science/article/pii/S030645301400399
The effect of elastic therapeutic taping on lumbar extensor isokinetic performance
Objective: To investigate the effects of elastic therapeutic tape when applied overlaying the lumbar extensors on different measures of muscle performance, compared to a placebo taping technique and a no-tape control.
Relevance: Elastic therapeutic tape is frequently used as an adjunct to enhance athletic performance amongst athletes. However, limited research exists supporting its application on isokinetic performance of the lumbar extensor muscles.
Methods: A cross-sectional experimental study. 21 participants received three taping conditions in a randomised order: elastic therapeutic tape, a placebo tape and a no-tape control. Peak torque, the time taken to reach peak torque and peak velocity were measured using an isokinetic dynamometer.
Analysis: Friedman’s test and post-hoc Wilcoxon signed-rank test were used to determine the statistical differences between the three taping conditions. Level of significance was set at 0.05.
Results: A statistically significant improvement in peak lumbar extensor torque was observed when comparing elastic therapeutic tape with the no-tape control (p 0.05).
Conclusions: Results demonstrate that the application of elastic therapeutic tape overlaying the primary lumbar extensors significantly improves the maximal lumbar extension peak torque in healthy, asymptomatic adults
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How can mastery learning promote inclusion in the science classroom?
Mastery learning is not a new concept, as it has been around for many years and will continue to feature in the educational scene as educators explore how it can be utilised to promote learning, despite the varying views regarding its impact on pupils’ learning and progress. The purpose of this article is to amplify the concept of mastery learning and its place in promoting inclusive learning among science pupils, and to highlight reasons why this pedagogy should be considered by science teachers
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