Novel non-aqueous symmetric redox materials for redox flow battery energy storage

Redox flow batteries are promising energy storage devices for grid-scale applications due to their decoupled power and capacity. The utilisation of non-aqueous electrolytes, as opposed to conventional water-based electrolytes, is a promising pathway for achieving techno-economic targets via advancements in energy density. Herein a selection of novel redox materials were explored for application as symmetric redox flow battery electrolytes whereby the same compound is used in both the battery cathode and anode reactions. Metal coordination compounds such as Co(II) complexes with tridentate azole-pyridine ligands demonstrated good long-term stability and cell potentials in excess of 1.5 V, however low solubility due to their large size is problematic. Smaller metal complexes with bidentate dithiolene ligands gave promising redox properties however instability of charged oxidation states causes rapid decomposition of the inorganic electrolyte. Similar instability was observed for a new symmetric redox material, croconate violet, which arises from high reactivity of radical states. The instability of the charged oxidation states of novel redox materials remains a challenge for the research field, as capacity loss has been reported in practically every novel non-aqueous redox material. Indeed, by developing the ferrocene-ferrocenium ion redox couple for non-aqueous cell characterisation, a noteworthy capacity loss over extended battery cycling experiments was observed. The present work therefore highlights the challenges with identifying suitable non-aqueous redox materials for application

The Missing Link: Jail and Prison Conditions in Criminal JusticeReform

The article examines the link between conditions in jails and prisons and broader criminal justice reform efforts

Topics in Energy Release and Particle Acceleration in the Heliosphere

This thesis investigates both the release of energy in solar flares, and the acceleration and transport of particles in various astrophysical situations. While numerical simulations are central to this thesis, these are always motivated by analytical arguments. A review of flare energy release is given in Chapter 2, with results presented in Chapters 3 and 4. The main goal of the flare work is to investigate the effect of viscosity on energy release rates. Scaling arguments and exact solutions of the magnetohydrodynamic equations are used to interpret the results of two-dimensional numerical simulations of magnetic reconnection. The results support viscous energy dissipation accounting for a significant fraction of flare energy release. Chapter 5 contains an introduction to astrophysical particle acceleration, using the Fokker-Planck formulation. The theory introduced in this chapter is used to study electron transport in solar flare loops (Section 5.5). A key aspect of the analysis is the expression of the Fokker-Planck equation as a system of stochastic differential equations. A generalisation to the flare loop hard X-ray emission prediction of Conway et al. (1998) is obtained, giving a stronger dependence on density for dispersed initial distributions. Chapter 6 uses the methods of the previous chapter to study the acceleration of cosmic-rays at the heliospheric termination shock. The applicability of the focused acceleration mechanism of Schlickeiser and Shalchi (2008) is examined using numerical simulations, which are interpreted using analytical arguments based on averaging the stochastic equations. The results show significant limitations in assuming a near-isotropic distribution, a requirement for the focused acceleration mechanism. In addition, momentum diffusion provides a significant effect that cannot be neglected. The theory is extended to include focused deceleration and pure momentum diffusion

The role of phosphorylation of Ire1 in its activation loop in regulation of its RNase activity

Ire1 is a protein kinase endoribonuclease (RNase) and a resident protein of the endoplasmic reticulum (ER) of Saccharomyces cerevisiae and a homologue to the Ire1a ER protein found in humans. Ire1 activates splicing of the mRNA of the unfolded protein response (UPR) gene HAC1. This splicing is a response to the accumulation of unfolded or misfolded proteins in the ER lumen. Splicing of HAC1 mRNA results in the translation of the Hac1 protein Hac1i which contains a bZIP transcription factor which promotes the expression of UPR-associated genes which ultimately leads to the alleviation of ER stress. The activation of Ire1 was previously thought to be dependent on phosphorylation within the Ire1 activation loop (a-loop). Here it is shown that in “phospho-dead” mutants, some level of splicing and UPR-activity is retained and that the aspartic acid residue (D836) within the a-loop allows for this retention. Furthermore, it was confirmed that mutation of D836 to alanine completely eliminates HAC1 mRNA splicing. This work suggests that phosphorylation of the a-loop is critical but not essential to RNase activation and the UPR

Hamilton-Jacobi Theory and Superintegrable Systems

Hamilton-Jacobi theory provides a powerful method for extracting the equations of motion out of some given systems in classical mechanics. On occasion it allows some systems to be solved by the method of separation of variables. If a system with n degrees of freedom has 2n - 1 constants of the motion that are polynomial in the momenta, then that system is called superintegrable. Such a system can usually be solved in multiple coordinate systems if the constants of the motion are quadratic in the momenta. All superintegrable two dimensional Hamiltonians of the form H = (p_x)sup2 + (p_y)sup2 + V(x,y), with constants that are quadratic in the momenta were classified by Kalnins et al [5], and the coordinate systems in which they separate were found. We discuss Hamilton-Jacobi theory and its development from a classical viewpoint, as well as superintegrability. We then proceed to use the theory to find equations of motion for some of the superintegrable Hamiltonians from Kalnins et al [5]. We also discuss some of the properties of the Poisson algebra of those systems, and examine the orbits

The importance of financial market development on the relationship between loan guarantees for SMEs and local market employment rates

We empirically examine whether a major government intervention in the small-firm credit market yields significantly better results in markets that are less financially developed. The government intervention that we investigate is SBA-guaranteed lending. The literature on financing small and medium size enterprises (SMEs) suggests that small firms may be exposed to a particular type of market failure associated with credit rationing. And SMEs in markets that are less financially developed will likely face a greater degree of this market failure. To test our hypothesis, we use the level of bank deposits per capita as our relative measure of financial market development, and we use local market employment rates as our measure of economic performance. After controlling for the appropriate cross-sectional market characteristics, we find that SBA-guaranteed lending has a significantly more (less) positive impact on the average annual level of employment when the local market is relatively less (more) financially developed. This result has important implications for public policy directives concerning where SBA-guaranteed lending should be directed.Small Business Administration ; Financial markets ; Small business - Finance ; Employment

Body fatness or anthropometry for assessment of unhealthy weight status? Comparison between methods in South African children and adolescents

A variety of methods are available for defining undernutrition (thinness/underweight/under-fat) and overnutrition (overweight/obesity/over-fat). The extent to which these definitions agree is unclear. The present cross-sectional study aimed to assess agreement between widely used methods of assessing nutritional status in children and adolescents, and to examine the benefit of body composition estimates. The main objective of the cross-sectional study was to assess underweight, overweight and obesity using four methods: (i) BMI-for-age using WHO (2007) reference data; (ii) BMI-for-age using Cole et al. and International Obesity Taskforce cut-offs; (iii) weight-for-age using the National Centre for Health Statistics/WHO growth reference 1977; and (iv) body fat percentage estimated by bio-impedance (body fat reference curves for children of McCarthy et al., 2006). Comparisons were made between methods using weighted kappa analyses. Subjects Individuals (n 1519) in three age groups (school grade 1, mean age 7 years; grade 5, mean age 11 years; grade 9, mean age 15 years). Results In boys, prevalence of unhealthy weight status (both under- and overnutrition) was much higher at all ages with body fatness measures than with simple anthropometric proxies for body fatness; agreement between fatness and weight-based measures was fair or slight using Landis and Koch categories. In girls, prevalence of unhealthy weight status was also higher with body fatness than with proxies, although agreement between measures ranged from fair to substantial. Methods for defining under- and overnutrition should not be considered equivalent. Weight-based measures provide highly conservative estimates of unhealthy weight status, possibly more conservative in boys. Simple body composition measures may be more informative than anthropometry for nutritional surveillance of children and adolescents

TIDieR-PHP: a reporting guideline for population health and policy interventions

We lack guidance on how to describe population health and policy (PHP) interventions in reports of evaluation studies. PHP interventions are legal, fiscal, structural, organisational, environmental, and policy interventions such as the regulation of unhealthy commodities, health service reorganisation, changes in welfare policy, and neighbourhood improvement schemes. Many PHP interventions have characteristics that are important for their implementation and success but are not adequately captured in the original Template for Intervention Description and Replication (TIDieR) checklist. This article describes the development of a revised reporting template for PHP interventions (TIDieR-PHP) and presents the checklist with examples for each ite