Fluid thermal actuator

Operational characteristics of actuator for spacecraft thermal control syste

Water utilization, evapotranspiration and soil moisture monitoring in the south east region of south Australia

There are no author-identified significant results in this report

WAMDII observation of an auroral atmosphere wave event

Field tests of WAMDII (Wide Angle Michelson Doppler Imaging Interferometer) on February 23 to 24, 1984 in Saskatoon produced wind images of the aurora that show well defined wave structures in lambda 5577. Wavelengths and velocities of these structures suggest an acoustic-gravity wave interpretation, but their short duration warrants their being termed an event. The Dopplergrams are presented with emphasis on the interpretation of the waves and a discussion of possible sources

Effect of disturbed flow on nanoparticle uptake in endothelial cells

n recent years, the focus of nanotechnology research has shifted from industrial applications, such as cosmetic or oil & gas (1,2), to those with a greater impact on medicine. Researchers are attempting to harness the ability of nanoparticles (NPs) to target specific areas of the body for the purpose of drug delivery or medical imaging (3,4). In order to predict how nanoparticles will accumulate once they enter the blood stream, a greater understanding of the effect of fluid flow on cellular interactions with NPs is required. Current research examines the effect of shape, size, and density on NP uptake (5), but very little attention is paid to the way in which flow disturbances affect how NPs accumulate. Disturbed flow regimes are characteristic in many biological systems in areas of vascular branching or curvature, regions of new vessel growth or in the presence of atherosclerotic plaques (6). In this study, a sudden expansion parallel plate flow chamber was used to examine the effects of flow rate (shear stress) as well as flow pattern on the uptake of NP by human umbilical vein endothelial cells (HUVEC). Fluorescence microscopy was used to image and quantify the presence of NPs following 30 minutes of exposure. As previous findings suggest (7), an increase in shear stress resulted in a decrease in NP uptake. Statically grown cells subject to short term flow and NP exposure exhibited equal accumulation in regions of disturbed and laminar flow, while preconditioning of HUVEC to flow for 24 hrs resulted in a difference in uptake between the two flow regimes. The results suggest that prolonged exposure to specific flow patterns may cause physiological changes that affect NP uptake. Such observations are important to ensure that in vitro studies are accurate predictors of NP behavior in biological models and warrant further exploration

Storyline description of Southern Hemisphere midlatitude circulation and precipitation response to greenhouse gas forcing

As evidence of climate change strengthens, knowledge of its regional implications becomes an urgent need for decision making. Current understanding of regional precipitation changes is substantially limited by our understanding of the atmospheric circulation response to climate change, which to a high degree remains uncertain. This uncertainty is reflected in the wide spread in atmospheric circulation changes projected in multimodel ensembles, which cannot be directly interpreted in a probabilistic sense. The uncertainty can instead be represented by studying a discrete set of physically plausible storylines of atmospheric circulation changes. By mining CMIP5 model output, here we take this broader perspective and develop storylines for Southern Hemisphere (SH) midlatitude circulation changes, conditioned on the degree of global-mean warming, based on the climate responses of two remote drivers: the enhanced warming of the tropical upper troposphere and the strengthening of the stratospheric polar vortex. For the three continental domains in the SH, we analyse the precipitation changes under each storyline. To allow comparison with previous studies, we also link both circulation and precipitation changes with those of the Southern Annular Mode. Our results show that the response to tropical warming leads to a strengthening of the midlatitude westerly winds, whilst the response to a delayed breakdown (for DJF) or strengthening (for JJA) of the stratospheric vortex leads to a poleward shift of the westerly winds and the storm tracks. However, the circulation response is not zonally symmetric and the regional precipitation storylines for South America, South Africa, South Australia and New Zealand exhibit quite specific dependencies on the two remote drivers, which are not well represented by changes in the Southern Annular Mode

VLBI Polarimetry of 177 Sources from the Caltech-Jodrell Bank Flat-spectrum Survey

We present VLBA observations and a statistical analysis of 5 GHz VLBI polarimetry data from 177 sources in the Caltech-Jodrell Bank flat-spectrum (CJF) survey. The CJF survey, a complete, flux-density-limited sample of 293 extragalactic radio sources, gives us the unique opportunity to compare a broad range of source properties for quasars, galaxies and BL Lacertae objects. We focus primarily on jet properties, specifically the correlation between the jet axis angle and the polarization angle in the core and jet. A strong correlation is found for the electric vector polarization angle in the cores of quasars to be perpendicular to the jet axis. Contrary to previous claims, no correlation is found between the jet polarization angle and the jet axis in either quasars or BL Lac objects. With this large, homogeneous sample we are also able to investigate cosmological issues and AGN evolution.Comment: Accepted to the Astrophysical Journal: 37 pages, 14 figure