Direct experimental evidence of time-temperature superposition at finite strain for an amorphous polymer network

The time-temperature superposition property of an amorphous polymer acrylate network is characterized at infinitesimal strain by standard dynamic mechanical analysis tests. Comparison of the shift factors determined in uniaxial tension and in torsion shows that both tests provide equivalent time-temperature superposition properties. More interestingly, finite strain uniaxial tension tests run until break at constant strain rate show that the acrylate network exhibits the same time-temperature superposition property at finite strain as at infinitesimal strain. Such original experimental evidence provides new insight for finite strain constitutive modelling of polymer amorphous networks.ANR REFORM 10-JCJC-091

Evaluation of the Population and Poverty Research Initiative (PopPov)

Since 2005, the William and Flora Hewlett Foundation, with collaboration and co-funding from research councils in the United Kingdom, the Netherlands, France, and Norway and from the World Bank, has invested in a portfolio of social science research on the relationship between population dynamics and micro- and macroeconomic outcomes. It is known as the Population and Poverty Research Initiative (PopPov), and its geographic focus is on subSaharan Africa (SSA). The starting premises that led to the development of PopPov were that evidence showing that population dynamics could affect economic outcomes might increase the interest of ministers of finance in funding population policies and that they might be most convinced by rigorous research done by respected economists. The core aim of the program has been to build (or, in some cases, rebuild) and advance the field of economic demography, orienting the work toward research that would be relevant for policy and would increase recognition by economic policymakers of the value of lowering the rate of population growth and investing in family planning (FP). The program also aimed to strengthen the capacity of researchers in SSA. The PopPov initiative tried to achieve these aims through four main components: (1) grants to support research on PopPov core topics of interest, (2) fellowships to support graduate students preparing their doctoral dissertations, (3) conferences and workshops to support the development of networking opportunities, and (4) other dissemination activities. PopPov has funded 56 doctoral fellows and, together with its partners, has supported 61 research projects. Seven international conferences and additional workshops have been held, and there have been several other dissemination activities. The Population Reference Bureau (PRB) and the Center for Global Development (CGD) have been the secretariats for PopPov. Since 2008, the Institute of International Education (IIE) has administered the fellowship program.In November 2012, to help guide its decisions about both the substance and means of future investments, the foundation issued a request for proposals (RFP) for an evaluation of PopPov. The RAND Corporation was selected to conduct the evaluation

An explicit MUSCL scheme on staggered grids with kinetic-like fluxes for the barotropic and full Euler system

International audienceWe present a second order scheme for the barotropic and full Euler equations. The scheme works on staggered grids, with numerical unknowns stored at dual locations, while the numerical fluxes are derived in the spirit of kinetic schemes. We identify stability conditions ensuring the positivity of the discrete density and energy. We illustrate the ability of the scheme to capture the structure of complex flows with 1d and 2d simulations on mac grids

Strategic decision quality in Flemish municipalities

Strategic planning (SP) has taken the public sector by storm because it is widely believed that SP’s approach to strategic decision-making strengthens strategic decision quality (SDQ) in public organizations. However, if or how SP relates to SDQ seems to lack empirical evidence. Drawing on survey data from 89 Flemish municipalities, we found that SP does improve SDQ if a systematic approach is taken and if top policy-makers and managers, as well as lower-level staff and external stakeholders, are involved

Probing the physics of narrow-line regions of Seyfert galaxies I: The case of NGC 5427

We have used the Wide Field Spectrograph (WiFeS) on the ANU 2.3m telescope at Siding Spring to observe the nearby, nearly face-on, Seyfert 2 galaxy, NGC 5427. We have obtained integral field spectroscopy of both the nuclear regions and the HII regions in the spiral arms. We have constrained the chemical abundance in the interstellar medium of the extended narrow line region (ENLR) by measuring the abundance gradient in the circum-nuclear \ion{H}{ii} regions to determine the nuclear chemical abundances, and to use these to in turn determine the EUV spectral energy distribution for comparison with theoretical models. We find a very high nuclear abundance, $\sim 3.0$ times solar, with clear evidence of a nuclear enhancement of N and He, possibly caused by massive star formation in the extended ($\sim 100$pc) central disk structure. The circum-nuclear narrow-line region spectrum is fit by a radiation pressure dominated photoionisation model model with an input EUV spectrum from a Black Hole with mass $5\times10^7 M_{\odot}$ radiating at $\sim 0.1$ of its Eddington luminosity. The bolometric luminosity is closely constrained to be $\log L_{\mathrm bol.} = 44.3\pm 0.1$ erg s$^{-1}$. The EUV spectrum characterised by a soft accretion disk and a harder component extending to above 15keV. The ENLR region is extended in the NW-SE direction. The line ratio variation in circum-nuclear spaxels can be understood as the result of mixing \ion{H}{ii} regions with an ENLR having a radius-invariant spectrum.Comment: Accepted for publication in Astronomy and Astrophysics, 14 pages, 13 figure

Time-Varying Textures

Essentially all computer graphics rendering assumes that the reflectance and texture of surfaces is a static phenomenon. Yet, there is an abundance of materials in nature whose appearance varies dramatically with time, such as cracking paint, growing grass, or ripening banana skins. In this paper, we take a significant step towards addressing this problem, investigating a new class of time-varying textures. We make three contributions. First, we describe the carefully controlled acquisition of datasets of a variety of natural processes including the growth of grass, the accumulation of snow, and the oxidation of copper. Second, we show how to adapt quilting-based methods to time-varying texture synthesis, addressing the important challenges of maintaining temporal coherence, efficient synthesis on large time-varying datasets, and reducing visual artifacts specific to time-varying textures. Finally, we show how simple procedural techniques can be used to control the evolution of the results, such as allowing for a faster growth of grass in well lit (as opposed to shadowed) areas

The assessment and appraisal of regenerative medicines and cell therapy products : an exploration of methods for review, economic evaluation and appraisal

BACKGROUND: The National Institute for Health and Care Excellence (NICE) commissioned a 'mock technology appraisal' to assess whether changes to its methods and processes are needed. This report presents the findings of independent research commissioned to inform this appraisal and the deliberations of a panel convened by NICE to evaluate the mock appraisal. METHODS: Our research included reviews to identify issues, analysis methods and conceptual differences and the relevance of alternative decision frameworks, alongside the development of an exemplar case study of chimeric antigen receptor (CAR) T-cell therapy for treating acute lymphoblastic leukaemia. RESULTS: An assessment of previous evaluations of regenerative medicines found that, although there were a number of evidential challenges, none was unique to regenerative medicines or was beyond the scope of existing methods used to conceptualise decision uncertainty. Regarding the clinical evidence for regenerative medicines, the issues were those associated with a limited evidence base but were not unique to regenerative medicines: small non-randomised studies, high variation in response and the intervention subject to continuing development. The relative treatment effects generated from single-arm trials are likely to be optimistic unless it is certain that the historical data have accurately estimated the efficacy of the control agent. Pivotal trials may use surrogate end points, which, on average, overestimate treatment effects. To reduce overall uncertainty, multivariate meta-analysis of all available data should be considered. Incorporating indirectly relevant but more reliable (more mature) data into the analysis can also be considered; such data may become available as a result of the evolving regulatory pathways being developed by the European Medicines Agency. For the exemplar case of CAR T-cell therapy, target product profiles (TPPs) were developed, which considered the 'curative' and 'bridging to stem-cell transplantation' treatment approaches separately. Within each TPP, three 'hypothetical' evidence sets (minimum, intermediate and mature) were generated to simulate the impact of alternative levels of precision and maturity in the clinical evidence. Subsequent assessments of cost-effectiveness were undertaken, employing the existing NICE reference case alongside additional analyses suggested within alternative frameworks. The additional exploratory analyses were undertaken to demonstrate how assessments of cost-effectiveness and uncertainty could be impacted by alternative managed entry agreements (MEAs), including price discounts, performance-related schemes and technology leasing. The panel deliberated on the range of TPPs, evidence sets and MEAs, commenting on the likely recommendations for each scenario. The panel discussed the challenges associated with the exemplar and regenerative medicines more broadly, focusing on the need for a robust quantification of the level of uncertainty in the cost-effective estimates and the potential value of MEAs in limiting the exposure of the NHS to high upfront costs and loss associated with a wrong decision. CONCLUSIONS: It is to be expected that there will be a significant level of uncertainty in determining the clinical effectiveness of regenerative medicines and their long-term costs and benefits, but the existing methods available to estimate the implications of this uncertainty are sufficient. The use of risk sharing and MEAs between the NHS and manufacturers of regenerative medicines should be investigated further. FUNDING: The National Institute for Health Research Health Technology Assessment programme