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Review of 'Harnessing Public Research for Innovation in the 21st Century: An International Assessment of Knowledge Transfer Policies. Edited by: Anthony Arundel, Suma Athreye and Sacha Wunsch-Vincent Cambridge and the World Intellectual Property Organization. Cambridge, United Kingdom. 2021. 502 pp. ISBN 9781108842792'
No full textControlling desolvation through polymer-assisted grinding
No full textWe demonstrate the ability to controllably desolvate a crystal-solvate system in step-wise fashion through polymer-assisted grinding by varying the type and proportion of polymer agent used. A plausible mechanistic explanation is proposed based on a combination of experimental evidence and computational analysis. Specifically, Raman spectroscopy, total scattering pair distribution function analysis and computed reaction energies suggest that the desolvation process is associated with preferred interactions between the solvent molecules and specific polymers. This approach could potentially be extended to any type of material, including heat-sensitive materials, where classical desolvation by thermal processes is not possible, and provides a new potential technique for formulation processing
A discontinuous model of duopoly with isoelastic demand and innovation costs
No full textThe paper studies the dynamic properties of a duopoly game in which firms strategically compete in quality-enhancing innovation investments and quantities. Market demands are assumed to be isolastic (reciprocal to the price) functions. The non-linearity of the demand functions, as already highlighted by T. Puu in [11], suggests the existence of complicated dynamics (cyclical or chaotic) in a standard dynamic Cournot duopoly. In addition to this, competition in innovation introduces the presence of discontinuities in the best response functions, expanding the set of possible equilibria (including asymmetric and multiple ones) of the standard Cournot duopoly and further enriching the dynamic features of the model.<br/
Flash Sintering, A Novel Technique for Nuclear Waste Management
No full textMixed uranium plutonium oxide (MOx) pellets are a potential candidate wasteform for plutonium disposition in a GDF. However, to manufacture MOx pellets suitable for disposal, homogenised powder feeds must be densified by a sintering process. This is an energy intensive and time-consuming process. Flash Sintering (FS) is an innovative technique in which an electric field is applied to the sample during the sintering process. It offers a more efficient and robust way to densify ceramic-containing nuclear material for disposal. The FS process requires significantly lower firing temperatures. It may therefore offer safety improvements when immobilising unique or problematic waste streams, due to the retention of volatile but long-lived minor actinides such as americium oxide. These would normally vaporise out of the MOx pellet during the high temperatures and long hold times in conventional sintering.We report the successful application of controlled current rate AC-FS flash sintering on both UO2 and CeO2 surrogate nuclear material for both fuel and waste applications, together with the microstructural evolution of pellets produced using both conventional (CeO2) and FS (CeO2 and UO2). These results demonstrate the possibility of forming different microstructures as a function of current density, in a fraction of conventional processing time. Future opportunities exist for expanding this work to the demonstration of FS on mixed CeO2 and UO2, as well as zirconia and neutron poison-doped materials for waste management applications.<br/
People in a Pandemic: Rethinking the role of ‘Community’ in Community Resilience Practices
No full textHow has the idea of community featured in attempts to build resilience to emergencies? The paper explores this question by presenting evidence from interviews with emergency responders across the world in the midst of the early and uncertain phases of the Covid-19 pandemic. Although reflecting different contexts, we discern two ways in which the notion of community featured in authorities’ narrations of their efforts to respond to the pandemic. Firstly, we demonstrate how community was deployed as a discursive mechanism that offered a particular framing of the vulnerabilities the pandemic instigated. Departing from accounts that reduce people’s identities to demographic categories, the deployment of community stressed that the pandemic’s effects should be understood by the different, yet coexistent, vulnerabilities it brought to the surface for people. Such renditions of vulnerability paved the way for styles of governance that prioritised adapting to the pandemic’s uncertain and indeterminate unfolding in the absence of prepared plans. Secondly, addressing a register of collective social life between individuals and the state, an emphasis on community engendered the decentralised arrangement of emergency governance with which resilience has become synonymous. Here, community proved pivotal in temporarily expanding resources to deal with an emergency whose effects threatened to exceed governments’ pre-existing capabilities. We substantiate this claim through examining how allusions to community worked to enrol non-state based efforts at response into a broader public security apparatus. Enveloped within the broader politics of emergency resilience, community shaped how the pandemic’s effects were understood whilst also ensuring adequate provisions for its governance
Impact of migrant and returning farmer professionalization on food production diversity
No full textSince the 2000s, there has been an increasing number of returning and migrant farmers across China. In 2012, China initiated a program for fostering professional farmers, which has caused greater changes for farmers and led to an agricultural shift towards commercial production. Migration has been recognized as a crucial factor affecting the diversity of agricultural production. However, scant attention has been paid to how different types of farmers influence agricultural diversification. Therefore, this study examines the influence of migrant farmers, returning farmers, and local non-migrant farmers on food production diversity. This study collected farm-level data on food production and farmers’ characteristics and applied a negative binomial regression model to estimate the impacts of different types of farmers on agricultural development. The results show that farms operated by migrant farmers had a significantly lower level of food production diversity while farms operated by returning farmers had no significant difference in food production diversity, using farms operated by local non-migrant farmers as the reference category. The variation in agricultural production diversity lies in differences in food production purposes, agricultural and market skills, and various risk-related capacities among the different types of farmers. Farm-level production specialization does not necessarily reduce food diversity and agrobiodiversity at the rural community and regional level
Energy Efficiency Optimization for PSOAM Mode-Groups based MIMO-NOMA Systems
No full textPlane spiral orbital angular momentum (PSOAM) mode-groups (MGs) and multiple-input multiple-output nonorthogonal multiple access (MIMO-NOMA) serve as two emerging techniques for achieving high spectral efficiency (SE) in the next-generation networks. In this paper, a PSOAM MGs based multi-user MIMO-NOMA system is studied, where the base station transmits data to users by utilizing the generated PSOAM beams. For such scenario, the interference between users in different PSOAM mode groups can be avoided, which leads to a significant performance enhancement. We aim to maximize the energy efficiency (EE) of the system subject to the constraints of the total transmission power and the minimum data rate. This designed optimization problem is non-convex owing to the interference among users, and hence is quite difficult to tackle directly. To solve this issue, we develop a dual layer resource allocation algorithm where the bisection method is exploited in the outer layer to obtain the optimal EE and a resource distributed iterative algorithm is exploited in the inner layer to optimize the transmit power. Besides, an alternative resource allocation algorithm with Deep Belief Networks (DBN) is proposed to cope with the requirement for low computational complexity. Simulation results verify the theoretical findings and demonstrate the proposed algorithms on the PSOAM MGs based MIMO-NOMA system can obtain a better performance comparing to the conventional MIMO-NOMA system in terms of EE
Race and Histories of Place: the racialisation of representational space in Govanhill and Butetown
No full textWe argue that the stories told about the histories and nature of places, are vehicles for narrating race. Drawing on interviews with professionals and community workers in Butetown in Cardiff and Govanhill in Glasgow, we explore how they negotiated – and contested - racialized histories of place, constructing different versions or claims to belong. Drawing on Henri Lefebvre’s spatial concepts we explore this conceptualisation through examination of the two areas which have distinct histories, and present experiences, of migration and racialization. In discussion of the accounts from the two distinct areas we show that narratives of the past have a political resonance which shape accounts of current experiences of migration. Accounts of place are often related in relationship to comparisons with and narratives of other places and to global processes of trade and migration. Whilst these racialised narratives are contested, they also shape responses to social problems faced by communities
Extracellular volume fraction improves risk-stratification for ventricular arrhythmias and sudden death in non-ischemic cardiomyopathy.
No full textObjectivesTo evaluate whether CMR-based parametric mapping and strain analysis can improve the risk-stratification for ventricular arrhythmias (VA) and sudden death (SD) in non-ischemic cardiomyopathy (NICM). Methods and resultsSecondary analysis of a prospective single-centre-registry (NCT02326324), including 703 consecutive NICM patients, 618 with extracellular volume (ECV) available. The combined primary endpoint included appropriate implantable cardioverter defibrillator therapies, sustained ventricular tachycardia, resuscitated cardiac arrest and SD. During a median follow-up of 21 months, 14 patients (2%) experienced the primary endpoint. Native T1 was not associated with the primary endpoint. Left ventricular global longitudinal strain lost its significant association after adjustment for left ventricular ejection fraction (LVEF). Among patients with ECV available, 11 (2%) reached the primary endpoint. Mean ECV was significantly associated with the primary endpoint and the best cut-off was 30%. ECV≥30% was the strongest independent predictor of the primary endpoint (HR 14.1, p=0.01) after adjustment for LGE and LVEF. ECV≥30% discriminated the arrhythmic risk among LGE+ cases and among those with LVEF≤35%. A simple clinical risk-stratification model, based on LGE, LVEF≤35% and ECV≥30%, achieved an excellent predictive ability (Harrell’s C 0.82) and reclassified the risk of 32% of the study population as compared to LVEF≤35% alone. Conclusions Comprehensive CMR evaluation in NICM showed that ECV was the only parameter with an independent and strong predictive value for VA/SD, on top of LGE and LVEF. A risk-stratification model based on LGE, LVEF≤35% and ECV≥30% achieved an excellent predictive ability for VA/SD
Effect of Temperature on the Preferential Intergranular Oxidation Susceptibility of Thermally-Treated Alloy 600
No full textThermally-treated Alloy 600 coupons were tested in pressurized water reactor simulated primary water at 320 °C and in high-pressure superheated steam at 400 °C to study the effect of a “semi-continuous” network of intergranular carbides on the stress corrosion cracking “precursors events”: preferential intergranular oxidation (PIO) and diffusion-induced grain boundary migration (DIGM). The intergranular carbides were partially consumed due to the environmental exposure, whereby the Cr released from the carbides contributed to the formation of the external oxide layer that limited both PIO and DIGM. The results were compared with previous studies in which similar coupons were exposed to H2-steam