Homomorphisms and Higher Extensions for Schur algebras and symmetric groups

This paper surveys, and in some cases generalises, many of the recent results on homomorphisms and the higher Ext groups for q-Schur algebras and for the Hecke algebra of type A. We review various results giving isomorphisms between Ext groups in the two categories, and discuss those cases where explicit results have been determined

Relative judgement is relatively difficult: evidence against the role of relative judgement in absolute identification

A variety of processes have been put forward to explain absolute identification performance. One difference between current models of absolute identification is the extent to which the task involves accessing stored representations in long-term memory (e.g. exemplars in memory, Kent & Lamberts, Journal of Experimental Psychology: Learning Memory and Cognition, 31, 289–305, 2005) or relative judgement (comparison of the current stimulus to the stimulus on the previous trial, Stewart, Brown & Chater, Psychological Review, 112, 881–911, 2005). In two experiments we explored this by tapping into these processes. In Experiment 1 participants completed an absolute identification task using eight line lengths whereby a single stimulus was presented on each trial for identification. They also completed a matching task aimed at mirroring exemplar comparison in which eight line lengths were presented in a circular array and the task was to report which of these matched a target presented centrally. Experiment 2 was a relative judgement task and was similar to Experiment 1 except that the task was to report the difference (jump-size) between the current stimulus and that on the previous trial. The absolute identification and matching data showed clear similarities (faster and more accurate responding for stimuli near the edges of the range and similar stimulus-response confusions). In contrast, relative judgment performance was poor suggesting relative judgement is not straightforward. Moreover, performance as a function of jump-size differed considerably between the relative judgement and absolute identification tasks. Similarly, in the relative judgement task, predicting correct stimulus identification based on successful relative judgement yielded the reverse pattern of performance observed in the absolute identification task. Overall, the data suggest that relative judgement does not underlie absolute identification and that the task is more likely reliant on an exemplar comparison process

An analogue of row removal for diagrammatic cherednik algebras

We prove an analogue of James–Donkin row removal theorems for diagrammatic Cherednik algebras. This is one of the first results concerning the (graded) decomposition numbers of these algebras over fields of arbitrary characteristic. As a special case, our results yield a new reduction theorem for graded decomposition numbers and extension groups for cyclotomic q-Schur algebras

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

The effects of the neuropeptide substance P on outcome following experimental traumatic brain injury in rats

Traumatic brain injury (TBI) today remains a major health and social problem for both developed and developing countries. It is the leading cause of death and disability under the age of 40, and despite the significance of this public health problem, no effective therapy exists. While a number of factors have been shown to be associated with the development of irreversible tissue injury after TBI, the formation of oedema and opening of the blood brain barrier (BBB) have been shown to be of major significance to outcome. Oedema formation in the brain, when left uncontrolled, results in increased intracranial pressure that may lead to a decrease in brain tissue perfusion, localised hypoxia and ischemia, and ultimately tissue herniation and death. The mechanisms associated with the development of oedema are largely unclear, and accordingly, current therapies are generally ineffective, often resulting in dehydration, hypotension and renal problems. This thesis describes the characterisation of neurogenic inflammation in the development of post-traumatic brain oedema and functional deficits, and particularly the role of substance P (SP) in mediating their development, using rodent models of both focal and diffuse TBI. Results from this thesis demonstrate that increased SP immunoreactivity, particularly at the level of the vasculature, is a ubiquitous feature of TBI implying a potential role in the breakdown of the blood brain barrier (BBB) following TBI. This was confirmed through the use of the NK[subscript 1] receptor antagonists, which attenuated BBB and oedema formation as well as deleterious morphological events such as dark cell change and axonal injury. The NK[subscript 1] receptor antagonists also resulted in an associated improvement in both motor and cognitive deficits, as assessed using a battery of functional outcome tests. Possible mechanisms of action of the NK[subscript 1] receptor antagonist included effects on the BBB, SP release, intracellular free magnesium concentration and aquaporin-4 channels. Neuroprotection could be facilitated with administration of a non-lipid permeable NK[subscript 1] receptor antagonist in the immediate postinjury period, or up to 12 h after TBI with a lipid permeable NK[subscript 1] receptor antagonist, suggesting that this class of drugs have a clinically viable therapeutic window. We conclude that SP has a significant role in the secondary injury process following TBI and may offer a novel target for the development of interventional pharmacological strategies.Thesis (Ph.D.)--School of Medical Sciences, 2006

Module structure on Lie powers and natural coalgebra-split sub-Hopf algebras of tensor algebras

10.1017/S0013091510000015Proceedings of the Edinburgh Mathematical Society542467-50

Some calculations of Lie (n)max for low n

10.1016/j.jpaa.2008.04.011Journal of Pure and Applied Algebra212112570-2580JPAA