Atmospheric deposition at groundwater dependent wetlands: implications for effective catchment management and Water Framework Directive groundwater classification in England and Wales

This report is the product of an Environment Agency (EA) contract co-funded by the British Geological Survey (NERC) to review and collate information regarding atmospheric and terrestrial nutrient loading at groundwater dependent terrestrial ecosystems (GWDTEs) in both England and Wales (the inclusion of Welsh sites are covered by the co-funding from BGS and not from EA funding. Many GWDTEs are low nutrient systems therefore any increase in loading can have a detrimental effect upon the ecology. In order to better protect GWDTEs in England and Wales it has become increasingly important to understand the sources of nutrients so that effective regulation and management can be applied to return the GWDTEs into favourable condition. This report highlights many knowledge gaps and also provides the first comparison of two national assessments, Critical Load (assessment of atmospheric deposition) and Threshold Value (assessment of groundwater nitrate levels). It shows that nearly 90% of the GWDTEs in England and Wales exceed their Critical Load for atmospheric deposition. Implications for future Water Framework Directive classification cycles are highlighted. Suggestions are made for suitable GWDTEs to be included in a future research project. The project will aim to provide a methodology to define source attribution from both atmospheric and terrestrial nutrients, enabling environment managers to make effective decisions to project GWDTEs

Control of the properties of semiconducting thin films deposited using magnetron sputtering

The objective of the work was to deposit semiconducting thin films with controlled properties using unbalanced reactive magnetron sputtering. It was decided to utilise this technique because it offers high deposition rate and controllable in-situ ion bombardment of the growing film, desirable attributes from both research and production perspectives. Sputtering from a metal cathode in a reactive gas atmosphere introduces process instabilities which can result in a low degree of control over the stoichiometry, optical, electrical and structural properties of the films. Whilst the focus of the study was to achieve repeatable control over semiconducting film properties, additional areas of interest associated with the reactive sputtering process were investigated as the project developed. Improvements in magnetron design have been made to remove iron contamination from the extended poles, at the same time improving cathode utilisation. A new technique of bonding polycrystalline silicon cathodes to cooling shims has been developed using a sputtered threemetal multilayer process. DC sputtering of silicon in the presence of oxygen, nitrogen, nitrogen and oxygen, and nitrogen and air has been used to produce films of refractive index between 2.27 and 1.45 at rates between 0.5 and 2 nms-1 depending on composition. Refractive index and optical transmittance of the films have been closely controlled by varying gas flow and composition, and substitution of air for oxygen increased the sensitivity so that indices of oxy-nitride films could be tailored to one decimal place. The deposition of Indium-tin-oxide (ITO) onto glass substrates has been investigated, using a feedback control loop to control the otherwise unstable process...cont'

Recently published papers: Bugs, fluids, obesity and food

Recently published papers: Bugs, fluids, obesity and foo

Towards MRI microarrays

Superparamagnetic iron oxide nanometre scale particles have been utilised as contrast agents to image staked target binding oligonucleotide arrays using MRI to correlate the signal intensity and relaxation times in different NMR fluids

Evidence of Gene Conversion in Genes Encoding the Gal/GalNac Lectin Complex of Entamoeba

The human gut parasite Entamoeba histolytica, uses a lectin complex on its cell surface to bind to mucin and to ligands on the intestinal epithelia. Binding to mucin is necessary for colonisation and binding to intestinal epithelia for invasion, therefore blocking this binding may protect against amoebiasis. Acquired protective immunity raised against the lectin complex should create a selection pressure to change the amino acid sequence of lectin genes in order to avoid future detection. We present evidence that gene conversion has occurred in lineages leading to E. histolytica strain HM1:IMSS and E. dispar strain SAW760. This evolutionary mechanism generates diversity and could contribute to immune evasion by the parasites

In search of Karl Polanyi’s international relations theory

Karl Polanyi is principally known as an economic historian and a theorist of international political economy. His theses are commonly encountered in debates concerning globalisation, regionalism, regulation and deregulation, and neoliberalism. But the standard depiction of his ideas is based upon a highly restricted corpus of his work: essentially, his published writings, in English, from the 1940s and 1950s. Drawing upon a broader range of Polanyi’s work in Hungarian, German, and English, this article examines his less well-known analyses of international politics and world order. It sketches the main lineaments of Polanyi’s international thought from the 1910s until the mid-1940s, charting his evolution from Wilsonian liberal, via debates within British pacifism, towards a position close to E. H. Carr’s realism. It reconstructs the dialectic of universalism and regionalism in Polanyi’s prospectus for postwar international order, with a focus upon his theory of ‘tame empires’ and its extension by neo-Polanyian theorists of the ‘new regionalism’ and European integration. It explores the tensions and contradictions in Polanyi’s analysis, and, finally, it hypothesises that the failure of his postwar predictions provides a clue as to why his research on international relations dried up in the 1950s

Shear History Extensional Rheology Experiment II (SHERE II) Microgravity Rheology with Non-Newtonian Polymeric Fluids

The primary objective of SHERE II is to study the effect of torsional preshear on the subsequent extensional behavior of filled viscoelastic suspensions. Microgravity environment eliminates gravitational sagging that makes Earth-based experiments of extensional rheology challenging. Experiments may serve as an idealized model system to study the properties of lunar regolith-polymeric binder based construction materials. Filled polymeric suspensions are ubiquitous in foods, cosmetics, detergents, biomedical materials, etc