Enhanced Quantum Reflection of Matter-Wave Solitons

Matter-wave bright solitons are predicted to reflect from a purely attractive potential well although they are macroscopic objects with classical particle-like properties. The non-classical reflection occurs at small velocities and a pronounced switching to almost perfect transmission above a critical velocity is found, caused by nonlinear mean-field interactions. Full numerical results from the nonlinear Schr\"{o}dinger equation are complimented by a two-mode variational calculation to explain the predicted effect, which can be used for velocity filtering of solitons. The experimental realization with laser-induced potentials or two-component Bose-Einstein condensates is suggested.Comment: 7 pages, 3 figures, to be published in Europhys. Let

Indigenous voices in climate change adaptation

AbstractThis project investigated how the deep knowledge of the Yorta Yorta people can be used to strengthen their participation and influence in the complex national and regional processes that determine how their traditional lands, which are in the highly-contested Murray-Darling Basin, are managed, leading to improved adaptation decisions both for the Yorta Yorta and the wider community.Through discussions with the Yorta Yorta over several years, the approach developed for the project was the creation of a Geographical Information System (GIS) mapping framework containing both Yorta Yorta knowledge and more conventional knowledge. GIS allows for mapping and layering of different types of data, allowing the Yorta Yorta to access and present their knowledge in ways that relate to Western decision-making processes. To do this, the project had four components:1. Development and testing of protocols and methodology for the collection and protection of Yorta Yorta knowledge. This was carried out through an intergenerational process, whereby Yorta Yorta youth were trained in cultural data collection techniques, and they interviewed Elders to capture the knowledge.2. Building of a GIS framework to integrate both the Yorta Yorta knowledge and more conventional data about the climate, hydrology and biodiversity of the Yorta Yorta area. For the first time this pulled together all of the conventional information normally used as a basis for natural resource management decisions. In addition, because the GIS database has been created and is owned by the Yorta Yorta means that they have something of value to bring to the discussions, so that they are able to participate in those discussions on equal terms.3. Exploration of the views of the broader community in the region regarding management of the region and adaptation alternatives through a stakeholder consultation process. The consultation identified the potential for greater use of science as a neutral arbiter in issues such as management of the Murray-Darling Basin, but even more important is the need for genuine, deep, open-minded dialogue with the community at all stages of decision-making, particularly at an early stage before proposals are put forward and views become entrenched.4. Identification of broader lessons for improving adaptation of First Nations communities in Australia from the experience of the Yorta Yorta and other communities around the country, through a national workshop. The key conclusion of the workshop was the urgent need to empower First Nation communities to make their own assessments and decisions on the best ways for them to respond to climate change.The project raised community awareness and knowledge and energised the Yorta Yorta youth to take an interest in their history and culture, and in the climate challenges facing their community. Overall the project has been a successful pilot demonstration of the utility of a GIS database to integrate Indigenous and conventional knowledge for better natural resource management outcomes and the project has increased the knowledge and capacity of the Yorta Yorta to engage in effective natural resource management and decision-making.Please cite this report as:Griggs, D, Lynch, A, Joachim, L, Zhu, X, Adler, C, Bischoff-Mattson, Z, Wang, P, Kestin, T 2013  Indigenous voices in climate change adaptation: Addressing the challenges of diverse knowledge systems in the Barmah-Millewa, National Climate Change Adaptation Research Facility, Gold Coast, pp.71AbstractThis project investigated how the deep knowledge of the Yorta Yorta people can be used to strengthen their participation and influence in the complex national and regional processes that determine how their traditional lands, which are in the highly-contested Murray-Darling Basin, are managed, leading to improved adaptation decisions both for the Yorta Yorta and the wider community.Through discussions with the Yorta Yorta over several years, the approach developed for the project was the creation of a Geographical Information System (GIS) mapping framework containing both Yorta Yorta knowledge and more conventional knowledge. GIS allows for mapping and layering of different types of data, allowing the Yorta Yorta to access and present their knowledge in ways that relate to Western decision-making processes. To do this, the project had four components:Development and testing of protocols and methodology for the collection and protection of Yorta Yorta knowledge. This was carried out through an intergenerational process, whereby Yorta Yorta youth were trained in cultural data collection techniques, and they interviewed Elders to capture the knowledge.Building of a GIS framework to integrate both the Yorta Yorta knowledge and more conventional data about the climate, hydrology and biodiversity of the Yorta Yorta area. For the first time this pulled together all of the conventional information normally used as a basis for natural resource management decisions. In addition, because the GIS database has been created and is owned by the Yorta Yorta means that they have something of value to bring to the discussions, so that they are able to participate in those discussions on equal terms.Exploration of the views of the broader community in the region regarding management of the region and adaptation alternatives through a stakeholder consultation process. The consultation identified the potential for greater use of science as a neutral arbiter in issues such as management of the Murray-Darling Basin, but even more important is the need for genuine, deep, open-minded dialogue with the community at all stages of decision-making, particularly at an early stage before proposals are put forward and views become entrenched.Identification of broader lessons for improving adaptation of First Nations communities in Australia from the experience of the Yorta Yorta and other communities around the country, through a national workshop. The key conclusion of the workshop was the urgent need to empower First Nation communities to make their own assessments and decisions on the best ways for them to respond to climate change.The project raised community awareness and knowledge and energised the Yorta Yorta youth to take an interest in their history and culture, and in the climate challenges facing their community. Overall the project has been a successful pilot demonstration of the utility of a GIS database to integrate Indigenous and conventional knowledge for better natural resource management outcomes and the project has increased the knowledge and capacity of the Yorta Yorta to engage in effective natural resource management and decision-making

Cavity optoelectromechanical regenerative amplification

Cavity optoelectromechanical regenerative amplification is demonstrated. An optical cavity enhances mechanical transduction, allowing sensitive measurement even for heavy oscillators. A 27.3 MHz mechanical mode of a microtoroid was linewidth narrowed to 6.6\pm1.4 mHz, 30 times smaller than previously achieved with radiation pressure driving in such a system. These results may have applications in areas such as ultrasensitive optomechanical mass spectroscopy

Xenon excimer emission from multicapillary discharges in direct current mode

Microdischarges in xenon have been generated in a pressure range of 400–1013 mbar with a fixed flow rate of 100 sccm. These microdischarges are obtained from three metallic capillary tubes in series for excimer emission. Total discharge voltage is thrice as large as that of a single capillary discharge tube at current levels of up to 12 mA. Total spectral irradiance of vacuum ultraviolet (VUV) emission also increases significantly compared to that of the single capillary discharge. Further, the irradiance of the VUV emission is strongly dependent on pressure as well as the discharge current

Farthest-Polygon Voronoi Diagrams

Given a family of k disjoint connected polygonal sites in general position and of total complexity n, we consider the farthest-site Voronoi diagram of these sites, where the distance to a site is the distance to a closest point on it. We show that the complexity of this diagram is O(n), and give an O(n log^3 n) time algorithm to compute it. We also prove a number of structural properties of this diagram. In particular, a Voronoi region may consist of k-1 connected components, but if one component is bounded, then it is equal to the entire region

Non-Gaussianity in the Weak Lensing Correlation Function Likelihood -- Implications for Cosmological Parameter Biases

We study the significance of non-Gaussianity in the likelihood of weak lensing shear two-point correlation functions, detecting significantly non-zero skewness and kurtosis in one-dimensional marginal distributions of shear two-point correlation functions in simulated weak lensing data. We examine the implications in the context of future surveys, in particular LSST, with derivations of how the non-Gaussianity scales with survey area. We show that there is no significant bias in one-dimensional posteriors of $\Omega_{\rm m}$ and $\sigma_{\rm 8}$ due to the non-Gaussian likelihood distributions of shear correlations functions using the mock data ($100$ deg$^{2}$). We also present a systematic approach to constructing approximate multivariate likelihoods with one-dimensional parametric functions by assuming independence or more flexible non-parametric multivariate methods after decorrelating the data points using principal component analysis (PCA). While the use of PCA does not modify the non-Gaussianity of the multivariate likelihood, we find empirically that the one-dimensional marginal sampling distributions of the PCA components exhibit less skewness and kurtosis than the original shear correlation functions.Modeling the likelihood with marginal parametric functions based on the assumption of independence between PCA components thus gives a lower limit for the biases. We further demonstrate that the difference in cosmological parameter constraints between the multivariate Gaussian likelihood model and more complex non-Gaussian likelihood models would be even smaller for an LSST-like survey. In addition, the PCA approach automatically serves as a data compression method, enabling the retention of the majority of the cosmological information while reducing the dimensionality of the data vector by a factor of $\sim$5.Comment: 16 pages, 10 figures, published MNRA

Taste-Changing in Staggered Quarks

We present results from a systematic perturbative investigation of taste-changing in improved staggered quarks. We show one-loop taste-changing interactions can be removed perturbatively by an effective four-quark term and calculate the necessary coefficients.Comment: 3 pages using espcrc2.sty and amsmath.sty, 1 Feynman diagram using feynmp.sty for Lattice2002(improve

Proenkephalin, neutrophil gelatinase-associated lipocalin, and estimated glomerular filtration rates in patients with sepsis

Background: Proenkephalin (PENK) has been suggested as a novel biomarker for kidney function. We investigated the diagnostic and prognostic utility of plasma PENK in comparison with neutrophil gelatinase-associated lipocalin (NGAL) and estimated glomerular filtration rates (EGFR) in septic patients. Methods: A total of 167 septic patients were enrolled: 99 with sepsis, 37 with septic shock, and 31 with suspected sepsis. PENK and NGAL concentrations were measured and GFR was estimated by using the isotope dilution mass spectrometry traceable-Modification of Diet in Renal Disease (MDRD) Study and three Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations: CKD-EPICr, CDK-EPICysC, and CKD-EPICr-CysC. The PENK, NGAL, and EGFR results were compared according to sepsis severity, presence or absence of acute kidney injury (AKI), and clinical outcomes. Results: The PENK, NGAL, and EGFR results were significantly associated with sepsis severity and differed significantly between patients with and without AKI only in the sepsis group (all P<0.05). PENK was superior to NGAL in predicting AKI (P=0.022) and renal replacement therapy (RRT) (P=0.0085). Regardless of the variable GFR category by the different EGFR equations, PENK showed constant and significant associations with all EGFR equations. Unlike NGAL, PENK was not influenced by inflammation and predicted the 30-day mortality. Conclusions: PENK is a highly sensitive and objective biomarker of AKI and RRT and is useful for prognosis prediction in septic patients. With its diagnostic robustness and predictive power for survival, PENK constitutes a promising biomarker in critical care settings including sepsis