A fascinating multifaceted redox-active chelating ligand: introducing the N,N′-dimethyl-3,3′-biquinoxalinium “methylbiquinoxen” platform

To intimately combine a chelating ligand function with the numerous properties of a viologen-like redox-active centre would offer a rare possibility to design controllable multi-redox states, whose properties arise from strongly correlated phenomena between the organic ligand as well as with any metalloid coordinated centres. Such a concept previously proved to be feasible, however is not widely applicable owing to challenges in terms of synthesis, isolation, and aerial sensitivity of both the ligand and its metal complexes. Here we report the first stable example of such a redox-active molecule, N,N′-dimethyl-3,3′-biquinoxalinium2+/˙+/0 “methylbiquinoxen, MBqn2+/˙+/0”, which shows a rich redox chemistry and chelates a metal ion in the case of the metal complex [CdCl2(MBqn0)]. This goes beyond what is possible to achieve using viologens, which are limited by not providing chelation as well as having no accessible biradicaloid state, corresponding to the neutral direduced MBqn0 open-shell behaviour we observe here

Institutional Approaches to Curriculum Design: Bolton’s Institutional Story

The JISC Curriculum Design Programme funded 12 projects over a four-year period with the aim of supporting Higher Education Institutions (HEI) to transform their approaches to curriculum design through the innovative use of technologies. This report explains the work of the Coeducate project including the projects achievements, findings, recommendations and what might be valuable to other Higher Education Institutions (HEI’s). The context in which the project operated is explained including the University technical systems

Energy Optimal Data Propagation in Wireless Sensor Networks

We propose an algorithm which produces a randomized strategy reaching optimal data propagation in wireless sensor networks (WSN).In [6] and [8], an energy balanced solution is sought using an approximation algorithm. Our algorithm improves by (a) when an energy-balanced solution does not exist, it still finds an optimal solution (whereas previous algorithms did not consider this case and provide no useful solution) (b) instead of being an approximation algorithm, it finds the exact solution in one pass. We also provide a rigorous proof of the optimality of our solution.Comment: 19 page

Visual stress responses to static images are associated with symptoms of Persistent Postural Perceptual Dizziness (PPPD)

This study funded by Wellcome [104943/Z/14/Z], Wellcome and Cardiff University ISSF [097824/Z/11/Z], and Health and Care Research Wales [SCF-18-1504].BACKGROUND: Images that deviate from natural scene statistics in terms of spatial frequency and orientation content can produce visual stress (also known as visual discomfort), especially for migraine sufferers. These images appear to over-activate the visual cortex. OBJECTIVE: To connect the literature on visual discomfort with a common chronic condition presenting in neuro-otology clinics known as persistent postural perceptual dizziness (PPPD). Sufferers experience dizziness when walking through highly cluttered environments or when watching moving stimuli. This is thought to arise from maladaptive interaction between vestibular and visual signals for balance. METHODS: We measured visual discomfort to stationary images in patients with PPPD (N=30) and symptoms of PPPD in a large general population cohort (N=1858) using the Visual Vertigo Analogue Scale (VVAS) and the Situational Characteristics Questionnaire (SCQ). RESULTS: We found that patients with PPPD, and individuals in the general population with more PPPD symptoms, report heightened visual discomfort to stationary images that deviate from natural spectra (patient comparison, F (1, 1865) = 29, p < 0.001; general population correlations, VVAS, rs (1387) = 0.46, p < 0.001; SCQ, rs (1387) = 0.39, p < 0.001). These findings were not explained by co-morbid migraine. Indeed, PPPD symptoms showed a significantly stronger relationship with visual discomfort than did migraine (VVAS, zH = 8.81, p < 0.001; SCQ, zH = 6.29, p < 0.001). CONCLUSIONS: We speculate that atypical visual processing – perhaps due to a visual cortex more prone to over-activation – may predispose individuals to PPPD, possibly helping to explain why some patients with vestibular conditions develop PPPD and some do not.PostprintPeer reviewe

Beyond MOOCs: Sustainable Online Learning in Institutions

This report sets out to help decision makers in higher education institutions gain a better understanding of the phenomenon of Massive Online Open Courses (MOOCs) and trends towards greater openness in higher education and to think about the implications for their institutions. The phenomena of MOOCs are described, placing them in the wider context of open education, online learning and the changes that are currently taking place in higher education at a time of globalisation of education and constrained budgets. The report is written from a UK higher education perspective, but is largely informed by the developments in MOOCs from the USA and Canada. A literature review was undertaken focussing on the extensive reporting of MOOCs through scholarly blogs, press releases as well as openly available reports and research papers. This identified current debates about new course provision, the impact of changes in funding and the implications for greater openness in higher education. The theory of disruptive innovation is used to help form the questions of policy and strategy that higher education institutions need to addres

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