932 research outputs found
The impact of the graduated driver licence scheme on road traffic accident youth mortality in New Zealand
This paper examines the impact of the introduction of New Zealand’s Graduated Driving Licence System (GDLS) on patterns of road traffic accident mortality amongst the young driving population from 1980 to 2001. Results show that the mortality rate has declined, but that rates in New Zealand are three times greater than in England and Wales and twice those of Scotland. When the data is adjusted to take account of differences in the minimum driving age, rates remain consistently higher in New Zealand and the proportional reduction in road traffic accident youth mortality is not significantly better than that experienced in Great Britain
Magnetised Thermal Self-focusing and Filamentation of Long-Pulse Lasers in Plasmas Relevant to Magnetised ICF Experiments
In this paper we study the influence of the magnetised thermal conductivity
on the propagation of a nanosecond laser in an
underdense plasma by performing simulations of a paraxial model laser in a
plasma with the full Braginskii magnetised transport coefficients. Analytic
theory and simulations show the shortening of the self-focal length of a laser
beam in a plasma as a result of the reduction of the plasma thermal
conductivity in a magnetic field. Furthermore the filamentation of a laser via
the thermal mechanism is found to have an increased spatial growth rate in a
magnetised plasma. We discuss the effect of these results on recent magnetised
inertial fusion experiments where filamentation can be detrimental to laser
propagation and uniform laser heating. We conclude the application of external
magnetic fields to laser-plasma experiments requires the inclusion of the
extended electron transport terms in simulations of laser propagation.Comment: 10 pages, 9 figure
A 3D <i>in vitro</i> model reveals differences in the astrocyte response elicited by potential stem cell therapies for CNS injury.
Aim: This study aimed to develop a 3D culture model to test the extent to which transplanted stem cells modulate astrocyte reactivity, where exacerbated glial cell activation could be detrimental to CNS repair success. Materials & methods: The reactivity of rat astrocytes to bone marrow mesenchymal stem cells, neural crest stem cells (NCSCs) and differentiated adipose-derived stem cells was assessed after 5 days. Schwann cells were used as a positive control. Results: NCSCs and differentiated Schwann cell-like adipose-derived stem cells did not increase astrocyte reactivity. Highly reactive responses to bone marrow mesenchymal stem cells and Schwann cells were equivalent. Conclusion: This approach can screen therapeutic cells prior to in vivo testing, allowing cells likely to trigger a substantial astrocyte response to be identified at an early stage. NCSCs and differentiated Schwann cell-like adipose-derived stem cells may be useful in treating CNS damage without increasing astrogliosis
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Engineered neural tissue with aligned Schwann cells supports neuronal regeneration <i>in vivo</i> and can be assembled using differentiated adipose-derived stem cells
A Comparative Study Of The Kayon In The Shadow Puppet Theatre Of Java, Bali And Kelantan: A Visual And Interpretive Understanding Of Its Symbols
The kayon of Java, known also as kakayonan in Bali, and referred to as the pohon beringin in Kelantan, is an ornate tree-or leaf-shaped puppet with which all shadow puppet theatre performances across these locations are formally opened and closed. A tree-shaped figure, with equivalent functions, does not appear in the shadow puppet theatre outside Indonesia and Malaysia. However, it appears in a disguised fashion in the Thai nang talung version of the shadow puppet theatre (the sage carries in his hand an object that resembles the kayon)
Scaling laws for electron kinetic effects in tokamak scrape-off layer plasmas
Tokamak edge (scrape-off layer) plasmas can exhibit non-local transport in
the direction parallel to the magnetic field due to steep temperature
gradients. This effect along with its consequences has been explored at
equilibrium for a range of conditions, from sheath-limited to detached, using
the 1D kinetic electron code SOL-KiT, where the electrons are treated
kinetically and compared to a self-consistent fluid model. Line-averaged
suppression of the kinetic heat flux (compared to Spitzer-Harm) of up to 50% is
observed, contrasting with up to 98% enhancement of the sheath heat
transmission coefficient, . Simple scaling laws in terms of basic SOL
parameters for both effects are presented. By implementing these scalings as
corrections to the fluid model, we find good agreement with the kinetic model
for target electron temperatures.
It is found that the strongest kinetic effects in are observed at
low-intermediate collisionalities, and tend to increase at increasing upstream
densities and temperatures. On the other hand, the heat flux suppression is
found to increase monotonically as upstream collisionality decreases. The
conditions simulated encompass collisionalities relevant to current and future
tokamaks.Comment: 24 pages, 14 figure
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