Within-guild dietary discrimination from 3-D textural analysis of tooth microwear in insectivorous mammals

Resource exploitation and competition for food are important selective pressures in animal evolution. A number of recent investigations have focused on linkages between diversification, trophic morphology and diet in bats, partly because their roosting habits mean that for many bat species diet can be quantified relatively easily through faecal analysis. Dietary analysis in mammals is otherwise invasive, complicated, time consuming and expensive. Here we present evidence from insectivorous bats that analysis of three-dimensional (3-D) textures of tooth microwear using International Organization for Standardization (ISO) roughness parameters derived from sub-micron surface data provides an additional, powerful tool for investigation of trophic resource exploitation in mammals. Our approach, like scale-sensitive fractal analysis, offers considerable advantages over twodimensional (2-D) methods of microwear analysis, including improvements in robustness, repeatability and comparability of studies. Our results constitute the first analysis of microwear textures in carnivorous mammals based on ISO roughness parameters. They demonstrate that the method is capable of dietary discrimination, even between cryptic species with subtly different diets within trophic guilds, and even when sample sizes are small. We find significant differences in microwear textures between insectivore species whose diet contains different proportions of ‘hard’ prey (such as beetles) and ‘soft’ prey (such as moths), and multivariate analyses are able to distinguish between species with different diets based solely on their tooth microwear textures. Our results show that, compared with previous 2-D analyses of microwear in bats, ISO roughness parameters provide a much more sophisticated characterization of the nature of microwear surfaces and can yield more robust and subtle dietary discrimination. ISO-based textural analysis of tooth microwear thus has a useful role to play, complementing existing approaches, in trophic analysis of mammals, both extant and extinct

Microwave intermodulation distortion of MgB2 thin films

The two tone intermodulation arising in MgB2 thin films deposited in-situ by planar magnetron sputtering on sapphire substrates is studied. Samples are characterised using an open-ended dielectric puck resonator operating at 8.8 GHz. The experimental results show that the third order products increase with the two-tone input power with a slope ranging between 1.5 and 2.3. The behaviour can be understood introducing a mechanism of vortex penetration in grain boundaries as the most plausible source of non linearities in these films. This assumption is confirmed by the analysis of the field dependence of the surface resistance, that show a linear behaviour at all temperatures under test.Comment: 13 pages, 3 figures; to be published in Appl. Phys. Let

Routes of salmonellae contamination in pig lairages and the development and evaluation of simple cleaning methods

The aim of this project was to identify, and validate, the best lairage-to-stunning practices to reduce cross-contamination, and to assess the general status of the lairage hygiene and lairage cleaning effectiveness in UK abattoirs

Broaching Badges for Learning

Learning related to Technology Enhanced Learning (TEL) is often delivered on demand using a variety of short, non-accredited methods, for example workshops, videos, online courses, self study. This is a pragmatic approach given that the rapid pace of change in TEL means that it is almost impossible for qualifications to stay relevant in terms of content, level or delivery method (House of Lords Digital Skills Committee (2014)). However each piece of learning stands independently and it can be difficult to later remember, let alone demonstrate meaningfully for PDR, CPD or to prospective employers. A potential solution that is gaining traction as a means of evidencing non-accredited learning is the use of Badges. These can be attached to a piece of learning and are aimed at transcending a single learning context to become transferable, lifelong assets. The Open University has identified badging as a key trend in accrediting informal learning. Collecting groups of badges have the potential to lead to coherent ‘qualifications’. Using badges, however presents issues about quality and portability though initiatives such as Mozilla’s Open Badge scheme are beginning to address these challenges through the embedding metadata into badges that gives information about content, level, issuing authority etc.. The aim of this project was to investigate the use of Digital Badges for staff development related to TEL.TFA

Sources of salmonella contamination in pig processing

The quantification of current state of the art on alternative/novel pig slaughtenng and processing procedures and pork decontamination was the initial aim of a project to reduce salmonella in pig processing for the UK Foods Standards Agency. To achieve these aims a survey of current commercial processing conditions was carried out, the published literature reviewed, and a review performed of technology from other sectors

Changes in carcass microbial distribution and water conditions during the scalding and dehairing of pig carcasses

Salmonella contaminatron is of major concern in the production of pork As part of a UK Food Standards Agency project looking at reducing salmonella contamrnation, a survey of current processing conditions in UK pig slaughterhouses and a review of published data identified pork scalding and dehairing systems as a likely major source of salmonella contamination during pork processing