On piecewise trivial Hopf—Galois extensions

We discuss a noncommutative generalization of compact principal bundles that can be trivialized relative to the finite covering by closed sets. In this setting we present bundle reconstruction and reduction

Covering and gluing of algebras and differential algebras

Extending work of Budzynski and Kondracki, we investigate coverings and gluings of algebras and differential algebras. We describe in detail the gluing of two quantum discs along their classical subspace, giving a C*-algebra isomorphic to a certain Podles sphere, as well as the gluing of U_{\sqrt{q}}(sl_2)-covariant differential calculi on the discs.Comment: latex2e, 27 page

Potential impact of climate change on improved and unimproved water supplies in Africa

With significant climate change predicted in Africa over the next century, this chapter explores a key question: how will rural water supplies in Africa be affected? Approximately 550 million people in Africa live in rural communities and are reliant on water resources within walking distance of their community for drinking water. Less than half have access to improved sources (generally large diameter wells, springs, or boreholes equipped with handpumps); the majority rely on unimproved sources, such as open water and shallow wells. Major climate modelling uncertainties, combined with rapid socio-economic change, make predicting the future state of African water resources difficult; an appropriate response to climate change is to assume much greater uncertainty in climate and intensification of past climate variability. Based on this assumption the following should be considered: 1. Those relying on unimproved water sources (300 million in rural Africa) are likely to be most affected by climate change because unimproved sources often use highly vulnerable water resources. 2. Improved rural water supplies in Africa are overwhelmingly dependent on groundwater, due to the unreliability of other sources. 3. Climate change is unlikely to lead to continent-wide failure of improved rural water sources that access deeper groundwater (generally over 20 metres below ground surface) through boreholes or deep wells. This is because groundwater-based domestic supply requires little recharge, and the groundwater resources at depth will generally be of sufficient storage capacity to remain a secure water resource. However, a significant minority of people could be affected if the frequency and length of drought increases – particularly those in areas with limited groundwater storage. 4. In most areas, the key determinants of water security will continue to be driven by access to water rather than absolute water availability. Extending access, and ensuring that targeting and technology decisions are informed by an understanding of groundwater conditions, will become increasingly important. 5. Accelerating groundwater development for irrigation could increase food production, raise farm incomes and reduce overall vulnerability. However, ad hoc development could threaten domestic supplies and, in some areas, lead to groundwater depletion. Although climate change will undoubtedly be important in determining future water security, other drivers (such as population growth and rising food demands) are likely to provide greater pressure on rural water supplies

Why Money Matters in Ecological Valuation

The ecosystem services movement was a reaction against nature being taken for granted in decision making. Put a value on the services that we enjoy from ecosystems and there is a better chance of showing their importance in economic and social development (Norgaard 2010). Yet there are still concerns that the monetization of these services is at best inappropriate and at worst flawed on ethical grounds and in terms of basic principles (Kapustka and McCormick 2015). Here, I argue that these views are missing the point about the need for a transparent approach to valuation

Psychosocial characteristics of patients seeking weight loss surgery

This study investigated the relationships between BMI, gender and depression, anxiety, self-esteem and disordered eating in people seeking weight loss (bariatric) surgery. The aim was to increase understanding of these relationships to improve selection of patients suitable for surgery. The study was a retrospective audit of data from 199 females and 59 males (mean BMI 48.3 ± 8.1kg/m²) who attended for surgical pre-assessment. Subjects completed the Hospital Anxiety and Depression Scale (HADS), The Impact of Weight on Quality of Life-Lite (IWQOL-Lite) and the Bulimic Investigatory Test, Edinburgh (BITE). Spearman’s correlations were used to investigate the relationships between BMI and the HADS anxiety and depression scores, the IWQOL-Lite self-esteem scores and the BITE symptom scale disordered eating scores. Mann-Whitney U tests were used to investigate gender differences in the psychosocial scores. There was no significant relationship between BMI and anxiety (r=-0.39; p=0.532), BMI and depression (r=-0.101; p=0.106), BMI and self- esteem (r=-0.017; p=0.788) or BMI and disordered eating (r=-0.109; p=0.081). There was a significant difference in HADS anxiety scores (p=0.004) between males (median=9) and females (median=12) and in IWQOL-Lite self-esteem scores (p=0.0005) between males (median=28) and females (median=33). There was no significant gender difference in HADS depression scores (p=0.03) or in BITE disordered eating scores (p=0.028). There was a significant difference in BMI (p=0.001) between males (median 49.5 kg/m²) and females (median 46.0 kg/m²). The results indicated that females seeking bariatric surgery were significantly more anxious and had lower self-esteem than males, and they had significantly lower BMIs than males. There was a weak negative correlation between BMI and the psychosocial scores indicating that people may be less distressed at higher BMIs but these results were not significant. Further research should investigate the relationships between the psychosocial variables in greater depth, to improve patient selection and outcomes after bariatric surgery