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Resetting the agenda : the makings of 'A New Era' of HIV policy in NSW
No full textThe New South Wales Government's NSW HIV Strategy 2012-2015: A New Era represented a punctuated shift of policy direction, and was remarkable for its ground-breaking declaration that HIV transmission could be virtually ended by 2020. This significant policy shift occurred after a long period of stability and only incremental change, some of it represented by policy decline as political and public interest in HIV waned. This article uses punctuated equilibrium theory to explore the conditions that allowed for change, and the roles played by new and long-standing actors in the HIV policy subsystem. It explains the importance of challenges to the policy image and the policy venue as key mechanisms that allowed new possibilities, created by advances in the scientific understanding of HIV, to be incorporated rapidly into government policy.7 page(s
The Biology of environmental stress : molecular biomarkers in Sydney rock oysters (Saccostrea glomerata)
No full textThis review describes our recent work on environmental stress in Sydney rock oysters, focusing on the identification of molecular biomarkers for ecotoxicological analysis. We begin by describing the environmental pressures facing coastal estuaries in Australia, with particular reference to Sydney Harbour. After providing that context, we summarise our transcriptional and proteomic analyses of Sydney rock oysters responding to chemical contamination and other forms of environmental stress. This work has shown that the intracellular processes of oysters are highly responsive to environmental threats. Our data agree with the broader literature, which suggests that there is a highly conserved intracellular stress response in oysters involving a limited number of biological processes. We conclude that many effective molecular markers for environmental biomonitoring are likely to lie within these biological pathways. Correction can be found in Environmental science : processes and impacts, Vol. 18. p. 1359, doi: http://dx.doi.org/10.1039/C6EM90036D11 page(s
Non-invasive detection and monitoring of biochemistry in cells and tissues by decomposing autofluorescence
No full textHyperspectral imaging based on endogenous contrast provides a new non-invasive method to characterise cells and tissues. Cellular content and maps of native fluorophores help monitor biological processes, with proper account of intrinsic cellular heterogeneity.2 page(s
Redox-freezing and nucleation of diamond via magnetite formation in the Earth's mantle
No full textDiamonds and their inclusions are unique probes into the deep Earth, tracking the deep carbon cycle to >800 km. Understanding the mechanisms of carbon mobilization and freezing is a prerequisite for quantifying the fluxes of carbon in the deep Earth. Here we show direct evidence for the formation of diamond by redox reactions involving FeNi sulfides. Transmission Kikuchi Diffraction identifies an arrested redox reaction from pyrrhotite to magnetite included in diamond. The magnetite corona shows coherent epitaxy with relict pyrrhotite and diamond, indicating that diamond nucleated on magnetite. Furthermore, structures inherited from h-Fe₃O₄ define a phase transformation at depths of 320-330 km, the base of the Kaapvaal lithosphere. The oxidation of pyrrhotite to magnetite is an important trigger of diamond precipitation in the upper mantle, explaining the presence of these phases in diamonds.7 page(s
Cross species applicability of anti-human plasma IgY affinity column
No full textIn order to improve the sensitivity of proteomic analysis, our group has developed a chicken antibody based column that has successfully depleted high abundance proteins (HAPs) from human plasma prior to mass spectrometry analysis. The use of chicken as a host for polyclonal antibodies production conveys many advantages, including but not limited to, the capabilities of producing large quantities of IgY antibodies with minimal antigen quantities and enhanced immunogenicity exhibited by their immune systems against foreign immunogens. In this study, we explored the ability to use an anti-human IgY affinity column with a variety of plasma samples derived from different animals and demonstrate this column’s ability to deplete the two most common HAPs (albumin and immunoglobulins) reproducibly in phylogenetically related species. Hence, our study highly recommends that IgY-based immune depletion technologies could be used to capture targeted proteins among phylogenetically related species without having to produce separate columns for each clade.5 page(s
Quantitative blood flow velocity imaging using laser speckle flowmetry
No full textLaser speckle flowmetry suffers from a debated quantification of the inverse relation between decorrelation time (τc) and blood flow velocity (V), i.e. 1/τc = αV. Using a modified microcirculation imager (integrated sidestream dark field - laser speckle contrast imaging [SDF-LSCI]), we experimentally investigate on the influence of the optical properties of scatterers on α in vitro and in vivo. We found a good agreement to theoretical predictions within certain limits for scatterer size and multiple scattering. We present a practical model-based scaling factor to correct for multiple scattering in microcirculatory vessels. Our results show that SDF-LSCI offers a quantitative measure of flow velocity in addition to vessel morphology, enabling the quantification of the clinically relevant blood flow, velocity and tissue perfusion.10 page(s
EV charging in a commercial hybrid AC/DC microgrid : configuration, control and impact analysis
No full textThe progressive deployment of electric vehicles (EVs) and the increased penetration of direct current (DC) and alternating current (AC) type renewable resources pave the path towards hybrid AC/DC microgrid operations. Considering the potential future participation of EVs in a hybrid AC/DC microgrid environment, this paper presents a generalized synopsis on EV charging in a commercial hybrid AC/DC microgrid. Constituents of this paper encompass the charger configurations, vehicle-to-grid (V2G) control strategies of individual chargers and their effects on the microgrid operations. Impacts of three types of EV chargers are considered in this paper which include three-phase AC and DC fast charging and single-phase residential charging. All configurations and their control strategies are developed in MATLAB/SIMULINK environment. Initial simulations are carried out considering real commercial load and solar irradiation data which shows stable microgird operations. Later the impacts of various types of EV charging on the AC and DC bus voltages and frequency of the commercial hybrid AC/DC microgrid are analyzed. The obtained results highlight the implications of bulk coordinated EV charging to reduce adverse operational impacts and network investment.6 page(s
Tsunami detection based on noisy sea surface height measurement
No full textThis paper presents an approach for the detection of early weak Tsunami in presence of large noise in sea surface height (SSH) measurements obtained such as using a satellite-carried global navigation satellite system (GNSS) receiver and the GNSS reflectometry (GNSS-R) technique. A sliding window moving average (SWMA) technique is proposed for detecting a Tsunami lead wave and a hypothesis testing method is developed to decide whether or not a Tsunami is present by examining the SWMA outputs against a predefined threshold. The proposed approach is evaluated using the 2011 Japan's Tsunami data collected by altimetry satellite Jason-1. Simulation results demonstrate that the proposed detect method considerably outperforms the existing methods.4 page(s
Improving multipath TCP for latency sensitive flows in the cloud
No full textRecent cloud datacenter network usually has multiple transmission paths for any pair of servers to increase the aggregate bandwidth and to improve the robustness of failure recovery. Therefore, Multipath TCP (MPTCP) is becoming one of the most important transport protocols exploring the multipath resource to improve the performance of cloud network. It is obvious that MPTCP could significantly increase the bandwidth for the throughput-oriented long flows by using multiple paths concurrently. However, for many latency-sensitive applications that require low latency other than high bandwidth, MPTCP performs poor. In this paper, we propose a set of extensions for MPTCP (called MPTCP-L) to improve its performance on the latency. Particularly, MPTCP-L replicates packets of latency-sensitive flows on two MPTCP subflows to proactively reduce retransmission delay of lost packets. Besides, we propose a rapid packet retransmission scheme that takes only 1-2 RTTs to recovery the lost packets for the TCP subflows of MPTCP. We conduct large scale simulations and testbed experiments based on real traffic load to evaluate MPTCP-L, and the results prove that MPTCP-L outperforms the standard MPTCP for latency-sensitive flows, and the induced redundancy overhead is negligible.6 page(s
Controversial age spreads from the main sequence turn-off and red clump in intermediate-age clusters in the LMC
No full textMost star clusters at an intermediate age (1−2 Gyr) in the Large and Small Magellanic Clouds show a puzzling feature in their color−magnitude diagrams (CMD) that is not in agreement with a simple stellar population. The main sequence turn-off of these clusters is much broader than expected from photometric uncertainties. One interpretation of this feature is that age spreads of the order of 200−500 Myr exist within individual clusters, although this interpretation is highly debated. Such large age spreads should affect other parts of the CMD, which are sensitive to age, as well. In this study, we analyze the CMDs of a sample of 12 intermediate-age clusters in the Large Magellanic Cloud that all show an extended turn-off using archival optical data taken with the Hubble Space Telescope. We fit the star formation history of the turn-off region and the red clump region independently. We find that in most cases, the age spreads inferred from the red clumps are smaller than those that result from the turn-off region. However, the age ranges that result from the red clump region are broader than expected for a single age. Only two out of 12 clusters in our sample show a red clump which seems to be consistent with a single age. As our results are ambiguous, by fitting the star formation histories to the red clump regions, we cannot ultimately tell if the extended main sequence turn-off feature is the result of an age spread or not. However, we do find that the width of the extended main sequence turn-off feature is correlated with the age of the clusters in a way which would be unexplained in the so-called age spread interpretation, but which may be expected if stellar rotation is the cause of the spread at the turn-off.16 page(s