151 research outputs found
Market and Economic Modelling of the Intelligent Grid: End of Year Report 2009
The overall goal of Project 2 has been to provide a comprehensive understanding of the impacts of distributed energy (DG) on the Australian Electricity System. The research team at the UQ Energy Economics and Management Group (EEMG) has constructed a variety of sophisticated models to analyse the various impacts of significant increases in DG. These models stress that the spatial configuration of the grid really matters - this has tended to be neglected in economic discussions of the costs of DG relative to conventional, centralized power generation. The modelling also makes it clear that efficient storage systems will often be critical in solving transient stability problems on the grid as we move to the greater provision of renewable DG. We show that DG can help to defer of transmission investments in certain conditions. The existing grid structure was constructed with different priorities in mind and we show that its replacement can come at a prohibitive cost unless the capability of the local grid to accommodate DG is assessed very carefully.Distributed Generation. Energy Economics, Electricity Markets, Renewable Energy
Efficacy of a platelet-rich plasma injection for the treatment of proximal hamstring tendinopathy: A pilot study
Objectives: To determine the efficacy of an ultrasound-guided platelet-rich plasma (PRP) injection in the treatment of patients with proximal hamstring tendinopathy (PHT).
Design: Pilot prospective cohort study
Methods: Administration of a single PRP injection under ultrasound guidance to 29 patients with PHT confirmed on magnetic resonance imaging (MRI). Pain, function and sporting activity were measured via the Victorian Institute of Sport Assessment-Proximal Hamstring Tendons (VISA-H) questionnaire, administered before injection and at 8-weeks follow-up.
Results: The study sample consisted of 22 females and 7 males with a mean age of 45.2 years (95% CI40.8–49.5). When comparing pre-injection VISA-H scores (mean: 43.90; 95% CI 37.77–50.03) with 8-week post-injection VISA-H scores (mean: 51.14; 95% CI 43.39–58.88) in the total sample of patients, no statistically significant difference was found (p = 0.14). When performing separate analyses for patients with mild (n = 9), moderate (n = 16) or marked (n = 4) PHT, no statistically significant difference was found in pre-and post-injection VISA-H scores for any of the groups (p = 0.86, p = 0.13, p = 0.28 respectively). 69%of patients reported no change in their ability to undertake sport or other physical activity at 8-weeks follow-up.
Conclusions: Patients with PHT receiving a PRP injection did not improve on clinical outcomes at 8-weeks follow-up
A 2 epoch proper motion catalogue from the UKIDSS Large Area Survey
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 2.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly citedThe UKIDSS Large Area Survey (LAS) began in 2005, with the start of the UKIDSS program as a 7 year effort to survey roughly 4000 square degrees at high galactic latitudes in Y, J, H and K bands. The survey also included a significant quantity of 2-epoch J band observations, with epoch baselines ranging from 2 to 7 years. We present a proper motion catalogue for the 1500 square degrees of the 2 epoch LAS data, which includes some 800,000 sources with motions detected above the 5 sigma level. We developed a bespoke proper motion pipeline which applies a source-unique second order polynomial transformation to UKIDSS array coordinates of each source to counter potential local non-uniformity in the focal plane. Our catalogue agrees well with the proper motion data supplied in the current WFCAM Science Archive (WSA) DR9 catalogue where there is overlap, and in various optical catalogues, but it benefits from some improvements. One improvement is that we provide absolute proper motions, using LAS galaxies for the relative to absolute correction. Also, by using unique, local, 2nd order polynomial tranformations, as opposed to the linear transformations in the WSA, we correct better for any local distortions in the focal plane, not including the radial distortion that is removed by their pipeline
Counterparts to the Nuclear Bulge X-ray source population
We present an initial matching of the source positions of the Chandra Nuclear
Bulge X-ray sources to the new UKIDSS-GPS near-infrared survey of the Nuclear
Bulge. This task is made difficult by the extremely crowded nature of the
region, despite this, we find candidate counterparts to ~50% of the X-ray
sources. We show that detection in the J-band for a candidate counterpart to an
X-ray source preferentially selects those candidate counterparts in the
foreground whereas candidate counterparts with only detections in the H and
K-bands are more likely to be Nuclear Bulge sources. We discuss the planned
follow-up for these candidate counterparts.Comment: 5 pages, 2 figures, 1 table, published in the proceedings of "A
population Explosion", AIP Conference Proceedings Volume 1010, pp. 117-12
The Nuclear Bulge extinction
We present a new, high resolution (5" per pixel) near-infrared extinction map
of the Nuclear Bulge using data from the UKIDSS-GPS. Using photometry from the
J, H and K-bands we show that the extinction law parameter is also highly
variable in this region on similar scales to the absolute extinction. We show
that only when this extinction law variation is taken into account can the
extinction be measured consistently at different wavelengths.Comment: 3 pages, 2 figures, published in the proceedings of "A population
Explosion", AIP Conference Proceedings Volume 1010, pp. 168-17
Spatial and temporal wolf distribution in the Beaver Hills
Wolves have recently recolonized the Beaver Hills region. The return of an apex predator may present interesting trophic consequences as well as being of management concern for agricultural activity in this landscape. Over approximately the past year wolf presence and movements have been monitored in Elk Island National Park (EINP) and the Cooking-Lake Blackfoot Provincial Recreation Area (BPRA) using remote camera traps. During this time, we have processed approximately 190,000 images and recorded 79 unique wolf observations. Using these remote images, we describe the spatial distribution of wildlife at camera sites. Similarly using GIS, we compare the diversity of wildlife observed at a particular camera location to the diversity of habitat types associated with the camera’s location. Secondly, we describe the temporal distribution of wildlife activity in EINP and BPRA as indicated by the distribution of when remote images were captured. Thirdly, we have observed a relationship between the proportions of wolves at cameras compared to coyotes. As the wolves recolonize EINP and BPRA, we hypothesize that we should observe spatial partitioning between them and the resident coyote population. However, we found that the number of wolf and coyote images was correlated across sites suggesting that the wolf population is currently not high enough to limit coyote activity through competitive exclusion. The results of these analyses can be used to better understand the relative abundance and distribution of wildlife on this landscape and in particular provide information for management to promote predator co-existence in this recently recolonized, multi-use agriculture landscape.
*Indicates faculty mentor
Optimizing procedures for genomic analyses of Beaver Hills canid scat
There are significant economic and ecological motivations to study the recently recolonized wolf (Canis lupus) population in the Beaver Hills region of Alberta, Canada. The reappearance of an apex predator presents challenges for land management. Competing claims for both agricultural and environmental priority necessitate an accurate description of the wolf population to inform an effective management solution. Faecal analysis presents a non-invasive technique for obtaining estimates of the population size, habitat use and genetic structure of wolves and coyotes (C. latrans). As a preliminary step, we sought to develop a procedure for obtaining and analyzing genetic material from canid scat. Ultimately this protocol will be applied to a 500-sample collection gathered in the Cooking Lake-Blackfoot Recreation Area and Elk Island National Park between May 2015 and January 2016. We compared and assessed protocols for scat storage and handling, DNA extraction and diagnostic molecular analyses. Extractions performed on scat samples stored at -20oC using the QIAmp Stool protocol produced DNA that could be successfully amplified using Scat ID primers. Diagnostic restriction digests match published fragment patterns for Alberta canids (i.e., dog and wolf). Based on these findings we present a protocol for species identification from canid scat collected in the Beaver Hills region.
*Indicates faculty mentor
Scat Based Dietary Analysis of Beaver Hills Canids
Recently, the Cooking Lake Blackfoot Provincial Recreation Area (BPRA), has been recolonized by wolves, an apex predator. The potential inclusion of domestic ungulates into the wolf diet through depredation events poses concerns for the local grazing community. Additionally, the arrival of an apex predator may have trophic consequences for the coyote, the current top predator in the BPRA. The diet of canids in the BPRA is being determined using scat analysis. A small sample of each collected scat is cleaned with acetone to isolate twenty representative hairs and/or presence of other food for identification. During the summer season, results indicate that canid diet is primarily composed of insects, berries, and small mammals. A comparison of the girth and composition of canid scat suggests that as scat diameter increases the likelihood of the scat containing large mammals and plants increases, as does the likelihood of a given scat being from a wolf. Smaller scats were found to contain more insects and small mammals. These results suggest that, during the summer of 2015, domestic ungulates play a very small role in the diet of canids, an observation confirmed by the grazing association as only one calf was depredated. The results also suggest that the recolonizing and resident canids are currently competing in terms of diet but that as the wolf population increases we expect to see a divergence in diet due to resource partitioning. Further genetic work to confirm the species of scat is ongoing.
*Indicates faculty mentor
The Multiplicity of M-Dwarfs in Young Moving Groups
We image 104 newly identified low-mass (mostly M-dwarf) pre-main sequence
members of nearby young moving groups with Magellan Adaptive Optics (MagAO) and
identify 27 binaries with instantaneous projected separation as small as 40
mas. 15 were previously unknown. The total number of multiple systems in this
sample including spectroscopic and visual binaries from the literature is 36,
giving a raw multiplicity rate of at least for this
population. In the separation range of roughly 1 - 300 AU in which infrared AO
imaging is most sensitive, the raw multiplicity rate is at least
for binaries resolved by the MagAO infrared camera (Clio). The
M-star sub-sample of 87 stars yields a raw multiplicity of at least
over all separations, for secondary
companions resolved by Clio from 1 to 300 AU ( for all known
binaries in this separation range). A combined analysis with binaries
discovered by the Search for Associations Containing Young stars shows that
multiplicity fraction as a function of mass and age over the range of 0.2 to
1.2 and 10 - 200 Myr appears to be linearly flat in both parameters
and across YMGs. This suggests that multiplicity rates are largely set by 100
Myr without appreciable evolution thereafter. After bias corrections are
applied, the multiplicity fraction of low-mass YMG members () is
in excess of the field.Comment: 25 page
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