title: Empirical testing of genuine savings as an indicator of weak sustainability: A three-country analysis of long-run trends

authors: Hanley, Nick

subjects: Social Sciences

abstract: Genuine Savings has emerged as a widely-used indicator of sustainable development. This approach to conceptualising what sustainability is about has strong links to work published by Anil Markandya and colleagues over 20 years ago. In this paper, we use long-term data stretching back to 1870 to undertake empirical tests of the relationship between Genuine Savings (GS) and future well-being for three countries: Britain, the USA and Germany. Our tests are based on an underlying theoretical relationship between GS and changes in the present value of future consumption. Based on both single country and panel results, we find evidence supporting the existence of a cointegrating (long run equilibrium) relationship between GS and future well-being, and fail to reject the basic theoretical result on the relationship between these two macroeconomic variables. This provides some support for the GS measure of weak sustainability.

text: Empirical testing of genuine savings as an indicator of weak sustainability: A three-country analysis of long-run trends Genuine Savings has emerged as a widely-used indicator of sustainable development. This approach to conceptualising what sustainability is about has strong links to work published by Anil Markandya and colleagues over 20 years ago. In this paper, we use long-term data stretching back to 1870 to undertake empirical tests of the relationship between Genuine Savings (GS) and future well-being for three countries: Britain, the USA and Germany. Our tests are based on an underlying theoretical relationship between GS and changes in the present value of future consumption. Based on both single country and panel results, we find evidence supporting the existence of a cointegrating (long run equilibrium) relationship between GS and future well-being, and fail to reject the basic theoretical result on the relationship between these two macroeconomic variables. This provides some support for the GS measure of weak sustainability.

year: 2016

title: GEANT4 simulation of the effects of Doppler energy broadening in Compton imaging

authors: Uche, Chibueze Zimuzo

subjects: Doppler broadening

abstract: A Monte Carlo approach was used to study the effects of Doppler energy broadening on Compton camera performance. The GEANT4 simulation toolkit was used to model the radiation transport and interactions with matter in a simulated Compton camera. The low energy electromagnetic physics model of GEANT4 incorporating Doppler broadening developed by Longo et al. was used in the simulations. The camera had a 9 × 9 cm scatterer and a 10 × 10 cm absorber with a scatterer to-absorber separation of 5 cm. Modelling was done such that only the effects of Doppler broadening were taken into consideration and effects of scatterer and absorber thickness and pixelation were not taken into account, thus a ‘perfect’ Compton camera was assumed. Scatterer materials were either silicon or germanium and the absorber material was cadmium zinc telluride. Simulations were done for point sources 10 cm in front of the scatterer. The results of the simulations validated the use of the low energy model of GEANT4. As expected, Doppler broadening was found to degrade the Compton camera imaging resolution. For a 140.5 keV source the resulting full-width-at-half-maximum (FWHM) of the point source image without accounting for Doppler broadening and using a silicon scatterer was 0.58 mm. This degraded to 7.1 mm when Doppler broadening was introduced and degraded further to 12.3 mm when a germanium scatterer was used instead of silicon. But for a 511 keV source, the FWHM was better than for a 140 keV source. The FWHM improved to 2.4 mm for a silicon scatterer and 4.6 mm for a germanium scatterer. Our result for silicon at 140.5 keV is in very good agreement with that published by An et al.

text: GEANT4 simulation of the effects of Doppler energy broadening in Compton imaging A Monte Carlo approach was used to study the effects of Doppler energy broadening on Compton camera performance. The GEANT4 simulation toolkit was used to model the radiation transport and interactions with matter in a simulated Compton camera. The low energy electromagnetic physics model of GEANT4 incorporating Doppler broadening developed by Longo et al. was used in the simulations. The camera had a 9 × 9 cm scatterer and a 10 × 10 cm absorber with a scatterer to-absorber separation of 5 cm. Modelling was done such that only the effects of Doppler broadening were taken into consideration and effects of scatterer and absorber thickness and pixelation were not taken into account, thus a ‘perfect’ Compton camera was assumed. Scatterer materials were either silicon or germanium and the absorber material was cadmium zinc telluride. Simulations were done for point sources 10 cm in front of the scatterer. The results of the simulations validated the use of the low energy model of GEANT4. As expected, Doppler broadening was found to degrade the Compton camera imaging resolution. For a 140.5 keV source the resulting full-width-at-half-maximum (FWHM) of the point source image without accounting for Doppler broadening and using a silicon scatterer was 0.58 mm. This degraded to 7.1 mm when Doppler broadening was introduced and degraded further to 12.3 mm when a germanium scatterer was used instead of silicon. But for a 511 keV source, the FWHM was better than for a 140 keV source. The FWHM improved to 2.4 mm for a silicon scatterer and 4.6 mm for a germanium scatterer. Our result for silicon at 140.5 keV is in very good agreement with that published by An et al.

year: 2011

title: “Seeing” Kāpō Māori: Making visible the experiences of Kāpō Māori during and after COVID-19

authors: Masters-Awatere, Bridgette

abstract: A scoping project focused on the intersection of Māori and the framing of vision impairments (disability) within the context of a pandemic response (in this instance COVID-19). Specifically, we were interested in the experiences of kāpō Māori during and post COVID-19 in order to centre the cultural and health needs of kāpō Māori in a culturally responsive manner. We highlight the aspirations that kāpō Māori have for themselves and their whānau, and to identify the facilitators and barriers that kāpō Māori and their whānau face in achieving these

text: “Seeing” Kāpō Māori: Making visible the experiences of Kāpō Māori during and after COVID-19 A scoping project focused on the intersection of Māori and the framing of vision impairments (disability) within the context of a pandemic response (in this instance COVID-19). Specifically, we were interested in the experiences of kāpō Māori during and post COVID-19 in order to centre the cultural and health needs of kāpō Māori in a culturally responsive manner. We highlight the aspirations that kāpō Māori have for themselves and their whānau, and to identify the facilitators and barriers that kāpō Māori and their whānau face in achieving these

year: 2021