Reddened, Redshifted, or Intrinsically Red? Understanding Near-Ultraviolet Colors of Type Ia Supernovae

Understanding the intrinsic colors of Type Ia supernovae (SNe Ia) is important to their use as cosmological standard candles. Understanding the effects of reddening and redshift on the observed colors are complicated and dependent on the intrinsic spectrum, the filter curves, and the wavelength dependence of reddening. We present ultraviolet and optical data of a growing sample of SNe Ia observed with the Ultra-Violet/Optical Telescope on the Swift spacecraft and use this sample to re-examine the near-UV (NUV) colors of SNe Ia. We find that a small amount of reddening (E(B-V)=0.2 mag) could account for the difference between groups designated as NUV-blue and NUV-red, and a moderate amount of reddening (E(B-V)=0.5 mag) could account for the whole NUV-optical differences. The reddening scenario, however, is inconsistent with the mid-UV colors and color evolution. The effect of redshift alone only accounts for part of the variation. Using a spectral template of SN2011fe we can forward model the effects of redshift and reddening and directly compare with the observed colors. We find that some SNe are consistent with reddened versions of SN2011fe, but most SNe Ia are much redder in the uvw1-v color than SN2011fe reddened to the same b-v color. The absolute magnitudes show that two of five NUV-blue SNe Ia are blue because their near-UV luminosity is high, and the other three are optically fainter. We also show that SN2011fe is not a "normal" SN Ia in the UV, but has colors placing it at the blue extreme of our sample

Behavioural simulation of biological neuron systems using VHDL and VHDL-AMS

The investigation of neuron structures is an incredibly difficult and complex task that yields relatively low rewards in terms of information from biological forms (either animals or tissue). The structures and connectivity of even the simplest invertebrates are almost impossible to establish with standard laboratory techniques, and even when this is possible it is generally time consuming, complex and expensive. Recent work has shown how a simplified behavioural approach to modelling neurons can allow “virtual” experiments to be carried out that map the behaviour of a simulated structure onto a hypothetical biological one, with correlation of behaviour rather than underlying connectivity. The problems with such approaches are numerous. The first is the difficulty of simulating realistic aggregates efficiently, the second is making sense of the results and finally, it would be helpful to have an implementation that could be synthesised to hardware for acceleration. In this paper we present a VHDL implementation of Neuron models that allow large aggregates to be simulated. The models are demonstrated using a system level VHDL and VHDL-AMS model of the C. Elegans locomotory system

An Intelligent Fuse-box for use with Renewable Energy Sources integrated within a Domestic Environment

This paper outlines a proposal for an intelligent fuse-box that can replace existing fuse-boxes in a domestic context such that a number of renewable energy sources can easily be integrated into the domestic power supply network, without the necessity for complex islanding and network protection. The approach allows intelligent control of both the generation of power and its supply to single or groups of electrical appliances. Energy storage can be implemented in such a scheme to even out the power supplied and simplify the control scheme required, and environmental monitoring and load analysis can help in automatically controlling the supply and demand profiles for optimum electrical and economic efficiency. Simulations of typical scenarios are carried out to illustrate the concept in operation

The employment experiences of graduates with disabilities in South Africa : challenges and resilience

A submitted thesis of Masters of Art in Social and Psychological Research, University of the Witwatersrand, Faculty of Humanities, School of Human and Community Development, 2017The career trajectory for persons with disabilities (PWDs) has largely been associated with decline and stagnation. Resilience and positive attributes have not been investigated related to graduates with disabilities (GWDs) successfully entering, adjusting to and further developing within the work environment. The aim of this study was to report on challenges, resilience and positive attributes amongst GWDs as a positive contributing factor to employment practices as well as policy. A participant sample of 6 employed GWDs (working age 26-45; 4 males and 2 females; 3 Black, 2 White and 1 Coloured) were individually interviewed. The participants’ disabilities consisted mainly of physical, hearing and visual impairments. The data was analysed using thematic and discourse analysis. Results show that despite the negative experiences encountered within the social and work environment, participants demonstrated resilience within their narratives and decision-making processes. A self-developed conceptual model of resilience and positive attributes was thus proposed to track this resilience. However, the resilience observed amongst participants did not fully reflect the existing definitions and theoretical frameworks around resilience. Critically re-examining these existing definitions and the theoretical framework showed new meanings can be derived with implications for policy and intervention. The fact that the majority of participants did not show awareness of or ownership of their resilience shows a missing key element – that they are not only making use of it, but they also do not even appear to realise its importance.MT201

Alcohol management plans and related alcohol reforms

Abstract Indigenous Justice Clearinghouse Research Brief 16 provides an analysis of Alcohol Management Plans (AMPs); a relatively new instrument joining the extensive range of regulations relating to alcohol supply and consumption. AMPs vary in design and implementation across Australia, and include strategies designed to reduce harms resulting from alcohol misuse. The authors chart the background and development of these instruments in Australia, as well as providing a comparison to international alcohol supply and control reforms. The authors find that evaluations in the public domain are limited. These evaluations appear to indicate that where AMPs are locally driven and owned, there are stronger and more sustainable outcomes. There is a good evidence base for the individual components that make up an AMP. Success has been achieved through alcohol restrictions, and both harm and demand reduction strategies have an evidence base as targeted interventions. The authors conclude that as more AMPs are implemented across Australia, there is a greater need for further research to better understand the process of implementation and how communities can work together with governments to design, implement and evaluate AMPs

Arbitrarily many independent observers can share the nonlocality of a single maximally entangled qubit pair

Alice and Bob each have half of a pair of entangled qubits. Bob measures his half and then passes his qubit to a second Bob who measures again and so on. The goal is to maximize the number of Bobs that can have an expected violation of the Clauser-Horne-Shimony-Holt (CHSH) Bell inequality with the single Alice. This scenario was introduced in [Phys. Rev. Lett. 114, 250401 (2015)] where the authors mentioned evidence that when the Bobs act independently and with unbiased inputs then at most two of them can expect to violate the CHSH inequality with Alice. Here we show that, contrary to this evidence, arbitrarily many independent Bobs can have an expected CHSH violation with the single Alice. Our proof is constructive and our measurement strategies can be generalized to work with a larger class of two-qubit states that includes all pure entangled two-qubit states. Since violation of a Bell inequality is necessary for device-independent tasks, our work represents a step towards an eventual understanding of the limitations on how much device-independent randomness can be robustly generated from a single pair of qubits.Comment: 4+7 pages, 2 figures, v2: minor updates to match published versio