The extremal algebra on two hermitians with square 1

Let Ea(u,v) be the extremal algebra determined by two hermitians u and v with u2 = v2 = 1. We show that: Ea(u,v) = {f=gu:f,g ε C(T)}, where T is the unit circle; Ea(u,v) is C*-equivelant to C*(G), where G is the infinite dihedral group; most of the hermitian elements k od Ea(u,v) have the property that kn is hermitian for all odd n but for no even n; any two hermitian words in G generate an isometric copy of Ea(u,v) in Ea(u,v)

Did working families' tax credit work? The final evaluation of the impact of in-work support on parents' labour supply and take-up behaviour in the UK

With micro-data from before and after a major reform in 1999 to the structure and form of in-work transfers in the UK, this paper uses a structural model of labour supply and programme participation to evaluate the labour market impact of Working Families' Tax Credit (WFTC). Estimates suggest that by 2002, WFTC had increased labour supply of lone mothers by around 5.11 percentage points, slightly reduced labour supply of mothers in couples by 0.57 percentage points, and increased the labour supply of fathers in couples by 0.75 percentage points, compared with the benefit that preceded it, called Family Credit. In aggregate, these changes are equivalent to a fall of 99,000 in the number of workless families with children, and a net increase in labour market participation of 81,000 workers. However, contemporaneous tax and benefit reforms acted to reduce the labour supply of parents, and so the overall impact of tax and benefit changes introduced since 1999 is lower than stated above. Participating in Family Credit, the UK's in-work programme before October 1999, conferred a utility loss as well as a utility gain from the extra income, but we find this utility cost of participation to be lower in the final year of WFTC than it was in the last year of Family Credit for lone mothers, and no different for individuals in couples: this in itself induced more lone mothers to work

Did Working Families' Tax Credit work? Analysing the impact of in-work support on labour supply and programme participation

With micro-data from before and after a major reform in 1999 to the structure and form of in-work transfers in the UK, this paper uses a structural model of labour supply and programme participation to show the impact of a reform to in-work support (Working Families' Tax Credit) on both labour supply and programme participation (or take-up). Estimates suggest that the changes in in-work incomes through the introduction of WFTC increased labour supply of lone mothers by around 4.6 percentage points, slightly reduced labour supply of mothers in couples by 0.2 percentage points, and increased the labour supply of fathers in couples by 0.8 percentage points, equivalent to a net increase in participation of 94,000 workers. Participating in Family Credit, the UK's in-work programme before October 1999, conferred a utility loss as well as a utility gain from the extra income, but we find this utility cost of participation to be lower under WFTC

Increasing resilience to natural hazards through crowd-sourcing in St. Vincent and the Grenadines

In this project we aim to demonstrate how volcanic environments exposed to multiple hazards tend to be characterised by a lack of relevant data available both in real time and over the longer term (e.g. months to years). This can be at least partially addressed by actively involving citizens, communities, scientists and other key stakeholders in the collection, analysis and sharing of observations, samples and measurements of changes in the environment. Such community monitoring and co-production of knowledge over time can also build trusting relationships and resilience (Stone et al. 2014). There are more than 100 institutions worldwide that monitor volcanoes and other natural hazards, contribute to early warning systems and are embedded in communities. They have a key role in building resilience alongside civil protection/emergency management agencies. In this report, we propose that such institutions are involved in big data initiatives and related research projects. In particular, we suggest that tools for crowd-sourcing may be of particular value. Citizen science, community monitoring and analysis of social media can build resilience by supporting: a) coordination and collaboration between scientists, authorities and citizens, b) decision-making by institutions and individuals, c) anticipation of natural hazards by monitoring institutions, authorities and citizens, d) capacity building of institutions and communities, and e) knowledge co-production. We propose a mobile phone app with a supporting website as an appropriate crowd-sourcing tool for St Vincent and the Grenadines. The monitoring institution is the key contact for users and leads on the required specifications based on local knowledge and experience. Remote support is provided from the UK on technical issues, research integration, data management, validation and evaluation. It is intended that the app facilitates building of long-term relationships between scientists, communities and authorities. Real-time contributions and analysis of social media support early warning, real-time awareness and real-time feedback enhancing the response of scientists and authorities. The app has potential to facilitate, for example, discussions on new or revised hazards maps, multiple hazard analysis and could contribute to real-time risk monitoring. Such an approach can be scaled up to facilitate regional use – and is transferable to other countries. Challenges of such an approach include data validation and quality assurance, redundancy in the system, motivating volunteers, managing expectations and ensuring safety. A combination of recruiting a core group of known and reliable users, training workshops, a code of conduct for users, identifying information influx thresholds beyond which external support might be needed, and continuing evaluation of both the data and the process will help to address these issues. The app is duplicated on the website in case mobile phone networks are down. Development of such approaches would fit well within research programmes on building resilience. Ideally such research should be interdisciplinary in acknowledgement of the diversity and complexity of topics that this embraces. There may be funding inequality between national monitoring institutions and international research institutions but these and other in-country institutions can help drive innovation and research if they are fully involved in problem-definition and research design. New innovations arising from increasing resolution (temporal and spatial) of EO products should lead to useful near-real time products from research and operational services. The app and website can ensure such diverse products from multiple sources are accessible to communities, scientists and authorities (as appropriate). Other innovations such as machine learning and data mining of time-series data collected by monitoring institutions may lead to new insights into physical processes which can support timely decision-making by scientists in particular (e.g. increasing alert levels)

Cost-effectiveness as a guide to pricing a new pharmaceutical product

No Abstract

The effects of cationic surfactants on marine biofilm growth on hydrogels

A method for the quantification of biofilm formation on hydrogel protective coatings for optical sensors and cameras has been developed using fluorescein diacetate (FDA) hydrolysis. In conjunction with these measurements the release of the fouling resistant cationic surfactants benzalkonium chloride, tallowbenzyldimethylammonium chloride and dicocodimethylammonium chloride was measured, using high performance liquid chromatography (HPLC), to enable correlation to be made between release and biofilm resistance and thus determine the active lifetime of such coatings. Results indicate that the twin-chained material, dicocodimethylammonium chloride, produced superior biofouling resistance as, at the 12 week time point, little fouling was detected on this coating. The hydrogel containing the long-chained tallowbenzyldimethylammonium chloride (mainly C-16 and C-18 chains) was the next best fouling resistant material, withstanding biofilm formation for 9 weeks. This correlates with the fact that each of these materials had an extremely slow to zero release rate, due to their irreversible binding to the hydrogel over the experimental timescale. In comparison the shorter chained benzalkonium chloride (mainly C-12 and C-14). showed signs of biofilm formation at the 3 week time point

Some extremal algebras for hermitians

We study three extremal Banach algebras: (a) generated by two hermitian unitaries; (b) generated by an element of norm 1 all of whose odd positive powers are hermitian; (c) generated by an element of norm 1 all of whose even positive powers are hermitian. In all three cases the numerical range is found for various elements. The second algebra is shown to be isometrically isomorphic to a subalgebra of the first. The third algebra is identified with a space of functions

Exercise and Academic Achievement in Children: Effects of Acute Class-Based Circuit Training

Purpose. For schools, the increasingly imposed requirement to achieve well in academic tests puts increasing emphasis on improving academic achievement. While treadmill exercise has been shown to have beneficial effects on cognitive function and cycling ergometers produce stronger effect sizes than treadmill running, it is impractical for schools to use these on a whole-class basis. There is a need to examine if more ecologically valid modes of exercise might have a similar impact on academic achievement. Circuit training is one such modality shown to benefit cognitive function and recall ability and is easily operationalised within schools. Methods. In a repeated measures design, twenty-six children (17 boys, 8 girls) aged 10-11 years (mean age 10.3; SD ± 0.46 years) completed the Wide Range Achievement Test (WRAT 4) at rest and following 30 minutes of exercise. Results. Standardised scores for word reading were significantly higher post exercise (F(1,18) = 49.9, p = 0.0001) compared to rest. In contrast, standardised scores for sentence comprehension (F(1,18) = 0.078, p = 0.783), spelling (F(1,18) = 4.07, p = 0.06) mathematics (F(1,18) = 1.257, p = 0.277), and reading (F(1,18) = 2.09, p = 0.165) were not significantly different between rest and exercise conditions. Conclusions. The results of the current study suggest acute bouts of circuit based exercise enhances word reading but not other areas of academic ability in 10-11 year old children. These findings support prior research that indicates acute bouts of exercise can selectively improve cognition in children

Student perceptions and experiences of problem-based learning in first year undergraduate sports therapy

Problem-based learning (PBL) has long been used as a means to foster critical thinking and student autonomy. However, few studies have investigated the effectiveness of PBL in Sports Therapy. The aim of this study was to examine first year Sports Therapy students' perceptions of PBL. Results revealed that students perceived PBL as vocationally relevant, by enabling them to work in and across groups, whilst also engaging with a wider range and depth of information compared to more traditional methods of curriculum delivery. External observations of the lecturers input sessions were made by an impartial re- searcher. The implications of the study are that PBL appears to be a professionally suitable and appropriate learning modality for Sports Therapy students