A semi-implicit version of the MPAS-atmosphere dynamical core

An important question for atmospheric modeling is the viability of semi-implicit time integration schemes on massively parallel computing architectures. Semi-implicit schemes can provide increased stability and accuracy. However, they require the solution of an elliptic problem at each time step, creating concerns about their parallel efficiency and scalability. Here, a semi-implicit (SI) version of the Model for Prediction Across Scales (MPAS) is developed and compared with the original model version, which uses a split Runge-Kutta (SRK3) time integration scheme. The SI scheme is based on a quasi-Newton iteration toward a Crank-Nicolson scheme. Each Newton iteration requires the solution of a Helmholtz problem; here, the Helmholtz problem is derived, and its solution using a geometric multigrid method is described. On two standard test cases, a midlatitude baroclinic wave and a small-planet nonhydrostatic gravity wave, the SI and SRK3 versions produce almost identical results. On the baroclinic wave test, the SI version can use somewhat larger time steps (about 60%) than the SRK3 version before losing stability. The SI version costs 10%-20% more per step than the SRK3 version, and the weak and strong scalability characteristics of the two versions are very similar for the processor configurations the authors have been able to test (up to 1920 processors). Because of the spatial discretization of the pressure gradient in the lowest model layer, the SI version becomes unstable in the presence of realistic orography. Some further work will be needed to demonstrate the viability of the SI scheme in this case.UK Natural Environment Research Council as part of the G8 ICOMEX projec

Making and Sharing the Commons: Reimagining ‘the West’ as Riverlands, Sydney through a Dialogue between Design and Ethnography

Scholars from the social sciences and humanities are increasingly seeking to improve the relevance and social impact of their research beyond the academy. In this context, ‘designerly’ thinking and methods are being drawn on to inform social change agendas, and a range of new relationships and collaborations are forming around this node of activity. This article critically reflects on this trajectory through a dialogue between ethnography, design and theoretical principles from anthropology and human geography

Hydrodynamic modeling of tidal-fluvial flows in a large river estuary

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this recordThe transition between riverine and estuarine environments is characterised by a change from unidirectional to bidirectional flows, in a region referred to herein as the Tidally-Influenced Fluvial Zone (TIFZ). In order to improve our understanding of the hydrodynamics and morphodynamics of this zone, we present a combined field and numerical modelling study of the Columbia River Estuary (CRE), USA, tidally-influenced fluvial zone. The CRE is large measuring 40 km in length and between 5 and 10 km wide. A shallow water model (Delft3D) was applied in both 2D and 3D configurations and model sensitivity to the key process parameterizations was investigated. Our results indicate that a 2D model constrained within the estuary can sufficiently reproduce depth-averaged flow within the TIFZ of a stratified estuary. Model results highlight the interactions between tidal-, fluvial- and topographic-forcing that result in depth dependent tidal rectification, and thus zones of residual sediment transport that: i) may be flood-directed along shallow channel margins and in the lee of bars, and simultaneously ii) is ebb-directed within deeper channel thalwegs. This condition is enhanced at lower discharges, but increased fluvial discharge reduces the number and size of regions with net flood-directed sediment transport and flow. These sediment transport patterns provide a mechanism to extend the bar/island topography downstream, and generate flood-directed, ebb-directed, and symmetrical bedforms, all within the same channel. Analysis of the model data reveals flood-directed sediment transport is due to both tidal variability and mean flow. These results highlight the need to include the mean flow component (M0) when considering the long-term morphodynamic evolution in a TIFZ. Model results highlight the interactions between tidal-, fluvial- and topographic-forcing that result in depth dependent tidal rectification, and thus zones of residual sediment transport that: i) may be flood-directed along shallow channel margins and in the lee of bars, and simultaneously ii) is ebb-directed within deeper channel thalwegs. This condition is enhanced at lower discharges, but increased fluvial discharge reduces the number and size of regions with net flood-directed sediment transport and flow. These sediment transport patterns provide a mechanism to extend the bar/island topography downstream, and generate flood-directed, ebb-directed, and symmetrical bedforms, all within the same channel. Analysis of the model data reveals flood-directed sediment transport is due to both tidal variability and mean flow. These results highlight the need to include the mean flow component (M0) when considering the long-term morphodynamic evolution in a TIFZ

A new multi-modal dataset for human affect analysis

In this paper we present a new multi-modal dataset of spontaneous three way human interactions. Participants were recorded in an unconstrained environment at various locations during a sequence of debates in a video conference, Skype style arrangement. An additional depth modality was introduced, which permitted the capture of 3D information in addition to the video and audio signals. The dataset consists of 16 participants and is subdivided into 6 unique sections. The dataset was manually annotated on a continuously scale across 5 different affective dimensions including arousal, valence, agreement, content and interest. The annotation was performed by three human annotators with the ensemble average calculated for use in the dataset. The corpus enables the analysis of human affect during conversations in a real life scenario. We first briefly reviewed the existing affect dataset and the methodologies related to affect dataset construction, then we detailed how our unique dataset was constructed

Paradoxical roles of antioxidant enzymes:Basic mechanisms and health implications

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are generated from aerobic metabolism, as a result of accidental electron leakage as well as regulated enzymatic processes. Because ROS/RNS can induce oxidative injury and act in redox signaling, enzymes metabolizing them will inherently promote either health or disease, depending on the physiological context. It is thus misleading to consider conventionally called antioxidant enzymes to be largely, if not exclusively, health protective. Because such a notion is nonetheless common, we herein attempt to rationalize why this simplistic view should be avoided. First we give an updated summary of physiological phenotypes triggered in mouse models of overexpression or knockout of major antioxidant enzymes. Subsequently, we focus on a series of striking cases that demonstrate “paradoxical” outcomes, i.e., increased fitness upon deletion of antioxidant enzymes or disease triggered by their overexpression. We elaborate mechanisms by which these phenotypes are mediated via chemical, biological, and metabolic interactions of the antioxidant enzymes with their substrates, downstream events, and cellular context. Furthermore, we propose that novel treatments of antioxidant enzyme-related human diseases may be enabled by deliberate targeting of dual roles of the pertaining enzymes. We also discuss the potential of “antioxidant” nutrients and phytochemicals, via regulating the expression or function of antioxidant enzymes, in preventing, treating, or aggravating chronic diseases. We conclude that “paradoxical” roles of antioxidant enzymes in physiology, health, and disease derive from sophisticated molecular mechanisms of redox biology and metabolic homeostasis. Simply viewing antioxidant enzymes as always being beneficial is not only conceptually misleading but also clinically hazardous if such notions underpin medical treatment protocols based on modulation of redox pathways

The role of discharge variability in determining alluvial stratigraphy

We illustrate the potential for using physics-based modeling to link alluvial stratigraphy to large river morphology and dynamics. Model simulations, validated using ground penetrating radar data from the Río Paraná, Argentina, demonstrate a strong relationship between bar-scale set thickness and channel depth, which applies across a wide range of river patterns and bar types. We show that hydrologic regime, indexed by discharge variability and flood duration, exerts a first-order influence on morphodynamics and hence bar set thickness, and that planform morphology alone may be a misleading variable for interpreting deposits. Indeed, our results illustrate that rivers evolving under contrasting hydrologic regimes may have very similar morphology, yet be characterized by marked differences in stratigraphy. This realization represents an important limitation on the application of established theory that links river topography to alluvial deposits, and highlights the need to obtain field evidence of discharge variability when developing paleoenvironmental reconstructions. Model simulations demonstrate the potential for deriving such evidence using metrics of paleocurrent variance

The “other” creatives : design and culture in Western Sydney

Western Sydney is an in-between place that is neither unified nor uniform and with constantly shifting borders; somewhere that is constantly in a state of transformation and becoming. Yet despite its vast and diverse geography, media representations tend to focus on the region's suburban aesthetic, and studies have shown that the area is recurrently portrayed as a cultural wasteland, the ugly “Other” Sydney characterised by social problems and neglect, where people are too focused on surviving to be “cultural” and referred to in shorthand as “Westies”. This stereotype has effectively operated as a brand that positioned Western Sydney as subservient to the rest of Sydney, affecting the social and economic interactions of people from the West. In recent times, some Western Sydney local councils have undertaken rebranding processes to make themselves more competitive, usually through celebrating demographic diversity, natural, sporting and recreation assets, and more recently, proximity to the new international airport. However, the region’s cultural assets—past, present, and emerging—have been overlooked, potentially hindering efforts to carve a more unique and authentic identity for the region, and limiting opportunities for locals and locales in the West. Following Melbourne and Sydney, Western Sydney is now Australia’s third-largest economy and is a key growth area, with new houses, jobs, and major projects in progress. Yet despite recent investigations into patterns of development and infrastructure growth, there have been few that explore Western Sydney-based creative industries in keeping with the studies conducted in areas surrounding other Australian cities. Instead, recurring discussions about Sydney’s creative scene tend to reinforce a stereotype, conceptualising creativity as a bohemian, inner city phenomenon with limited consideration given to creative industries situated in the apparently uncool outer suburbs, repeating a pattern of representation that situates the people of Western Sydney as outsiders. From the inside position of designer and Westie, this thesis explores how visual representations have helped to shape and sustain Western Sydney’s reputation as Other to Sydney and proposes how it could be repositioned through harnessing the cultural power of branding. Drawing from cultural studies, creative industries discourse, and branding practice, this thesis illuminates the connections between design and cultural agency in the West. In doing so, it contributes to the reconceptualization of Western Sydney’s identity during a time of unprecedented change and development

Evaluating Beaver Translocation Methods for Desert River Restoration

Wildlife translocation, or moving wild animals from their original home to a new location, is a common conservation practice; however, translocation programs have variable success rates. Beaver translocation is often used in stream restoration projects due to beavers’ role as ecosystem engineers—beavers enhance riparian habitat by building dams that hold water and create more diverse channels. Beaver translocation success is often limited by high mortality and long distance movement after release, and improvement in translocation methods is needed. My objective was to evaluate two methods of improving beaver translocation success in a degraded desert river in east-central Utah: beaver dam analog (BDA) installation and behavioral testing. Over two years before BDA installment, 39 nuisance beavers were captured, tagged, and translocated to the Price River. After 70 BDAs were installed, another 73 tagged beavers were translocated over two years. In the last two years of the study, I conducted behavioral testing while beavers were temporarily held in captivity. Over all four years, I monitored survival and movement of beavers and surveyed BDAs and natural beaver dams. Apparent survival (a combination of true survival and staying in the study area) was similar before and after BDA installation. Higher stream flow was linked to lower apparent survival. Mortality was generally caused by predators, and many beavers left the study area. At the end of data collection, no translocated beavers remained alive and in the study area. I observed beaver activity on two BDAs. Over the course of the study, there was a decrease in the number of natural dams due to extreme monsoon flooding in the final two years. We found relationships between beaver behavior and survival as well as distance traveled. More tame, less aggressive beavers survived longer, whereas bolder, more aggressive beavers moved farther. Our results suggest that while BDAs may not improve beaver translocation success in desert rivers, behavioral testing should be investigated further as a useful tool for prioritizing beavers for translocation. Translocation is a humane solution to human-beaver conflict, and with improved methods, it may be a valuable restoration practice in desert river ecosystems

Social Class

Discussion of class structure in fifth-century Athens, historical constitution of theater audiences, and the changes in the comic representation of class antagonism from Aristophanes to Menander

Search for squarks and gluinos with the ATLAS detector in final states with jets and missing transverse momentum using √s=8 TeV proton-proton collision data

A search for squarks and gluinos in final states containing high-p T jets, missing transverse momentum and no electrons or muons is presented. The data were recorded in 2012 by the ATLAS experiment in s√=8 TeV proton-proton collisions at the Large Hadron Collider, with a total integrated luminosity of 20.3 fb−1. Results are interpreted in a variety of simplified and specific supersymmetry-breaking models assuming that R-parity is conserved and that the lightest neutralino is the lightest supersymmetric particle. An exclusion limit at the 95% confidence level on the mass of the gluino is set at 1330 GeV for a simplified model incorporating only a gluino and the lightest neutralino. For a simplified model involving the strong production of first- and second-generation squarks, squark masses below 850 GeV (440 GeV) are excluded for a massless lightest neutralino, assuming mass degenerate (single light-flavour) squarks. In mSUGRA/CMSSM models with tan β = 30, A 0 = −2m 0 and μ > 0, squarks and gluinos of equal mass are excluded for masses below 1700 GeV. Additional limits are set for non-universal Higgs mass models with gaugino mediation and for simplified models involving the pair production of gluinos, each decaying to a top squark and a top quark, with the top squark decaying to a charm quark and a neutralino. These limits extend the region of supersymmetric parameter space excluded by previous searches with the ATLAS detector