226 research outputs found

    Section 4.1.3: Chironomid analysis: background, methods and geomorphological applications

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    Subfossil chironomids can provide both qualitative and quantitative reconstructions of past climatic and environmental conditions. Chironomid data are frequently used in palaeoecological and palaeoclimate studies, however geomorphological studies using chironomid data are currently few. Chironomid records are produced from lacustrine and alluvial sediments; these terrestrially based reconstructions can be of benefit to geomorphologists. In order to increase geomorphologists’ awareness of the potential of chironomid data this paper discusses the technique, with a particular focus on geomorphological applications. Chironomids and chironomid analysis are briefly introduced, and the methods used, both in the field and the laboratory, are outlined. Geomorphological studies which have utilised existing chironomid data, including glacial geomorphological, sea level and palaeohydrological studies, are discussed, as well as a chironomid study which produced data specifically aimed at investigating changing sea level. It is hoped that further applications for chironomid data in geomorphological studies will emerge

    Wild science: undertaking geomorphological research on youth expeditions

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    Every year the British Exploring Society takes large groups of young people (ages 16-25) on expeditions to remote areas of the world. The expeditions focus on adventure, science and media activities and are undertaken in wilderness environments. The nature of these expeditions allows many young people to be introduced to, and take part in, various scientific projects. In 2016 the expeditions were based in the Amazon (Manu, Peru) and the Himalayas (Ladakh, India). The scientific programmes of the two expeditions included geomorphological projects. In Peru the project explored the link between vegetation density, soil structure, and micro-climate along an anthropogenic gradient extending from a human inhabited area through to pristine primary rainforest. In India the project focused on recent environmental change in the Indian Himalaya, with geomorphological mapping a key component of the project. This will be combined with remote sensing data and palaeolimnological research. Through the inclusion of such fieldwork on the expeditions more young people will be introduced to a number of geomorphological ideas and techniques. It is hoped that there will be a number of benefits of participating in real-world research including: an increased interest and understanding of the natural environment; the acquisition of new fieldwork and scientific skills; the development of science communication skills; and something different to put on the CV

    A methodological proposal to investigate the long term storage of pollutants in freshwater sediment biofilms and their response to environmental disturbances.

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    This research will review novel methodologies for understanding the behaviour of microbial communities and their role in pollution storage. Freshwater sediments are inhabited by attached microbial communities (biofilms) which are responsible for the majority of a river's metabolic activity. Biofilms thus provide valuable information on the environmental quality of the river and its surrounding areas. Despite remediation of freshwater sediments, biofilms can still store large quantities of pollutants. Biofilms have the exceptional capacity to adjust to new conditions including natural and anthropogenic environmental disturbances. Gaining a more comprehensive understanding of biofilm behaviour is therefore fundamental to developing improved management strategies. The initial focus of this research will be in the River Doe Lea in North East Derbyshire. The River Doe Lea extends 18km from the South at its source near Tibshelf, to the North at its discharge at the River Rother. In the 1990s the River was famed for having the highest level of dioxins in the world, 27 times higher than the second most polluted. The acute cause of this was a single pollutant event, however the river has also been subjected to long term anthropogenic pollution through industry, agriculture, transport (railways, M1) and wastewater pollution. While previous studies by the Environment Agency have focused on the flow, chemical, biological and ecological quality of the river, no research has been conducted into the role and behaviour of biofilms

    Inappropriate flushing of menstrual sanitary products

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    This paper explores the disposal strategies of menstrual sanitary products through in-depth semi-structured interviews of women aged 18-30 years. There have been many educational campaigns to encourage solid stream waste disposal, however inappropriate disposal and blockages are still a major problem for the water industry. Whilst there have been quantitative studies exploring self-reporting of flushing norms, there is evidence to suggest these results may not take into account the complex set of socio-cultural factors associated with menstrual product disposal. Bridging this gap, our interviews found that although all participants had a desire to responsibly dispose, their ability to utilise solid waste streams or to minimise waste by using reusable products was not always possible because they felt, to some degree, restricted by the wider societal requirements for discretion and the design, accessibility and availability of bins and bathroom facilities. Based on these findings Industry recommendations are suggested

    In Situ Activation and Heterologous Production of a Cryptic Lantibiotic from an African Plant Ant-Derived Saccharopolyspora Species.

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    Most clinical antibiotics are derived from actinomycete natural products discovered at least 60 years ago. However, the repeated rediscovery of known compounds led the pharmaceutical industry to largely discard microbial natural products (NPs) as a source of new chemical diversity. Recent advances in genome sequencing have revealed that these organisms have the potential to make many more NPs than previously thought. Approaches to unlock NP biosynthesis by genetic manipulation of strains, by the application of chemical genetics, or by microbial cocultivation have resulted in the identification of new antibacterial compounds. Concomitantly, intensive exploration of coevolved ecological niches, such as insect-microbe defensive symbioses, has revealed these to be a rich source of chemical novelty. Here, we report the new lanthipeptide antibiotic kyamicin, which was generated through the activation of a cryptic biosynthetic gene cluster identified by genome mining Saccharopolyspora species found in the obligate domatium-dwelling ant Tetraponera penzigi of the ant plant Vachellia drepanolobium Transcriptional activation of this silent gene cluster was achieved by ectopic expression of a pathway-specific activator under the control of a constitutive promoter. Subsequently, a heterologous production platform was developed which enabled the purification of kyamicin for structural characterization and bioactivity determination. This strategy was also successful for the production of lantibiotics from other genera, paving the way for a synthetic heterologous expression platform for the discovery of lanthipeptides that are not detected under laboratory conditions or that are new to nature.IMPORTANCE The discovery of novel antibiotics to tackle the growing threat of antimicrobial resistance is impeded by difficulties in accessing the full biosynthetic potential of microorganisms. The development of new tools to unlock the biosynthesis of cryptic bacterial natural products will greatly increase the repertoire of natural product scaffolds. Here, we report a strategy for the ectopic expression of pathway-specific positive regulators that can be rapidly applied to activate the biosynthesis of cryptic lanthipeptide biosynthetic gene clusters. This allowed the discovery of a new lanthipeptide antibiotic directly from the native host and via heterologous expression

    The macroecology of animal versus wind pollination: ecological factors are more important than historical climate stability

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    Background: The relative frequency of wind and animal pollinated plants is non-randomly distributed across the globe and numerous hypotheses have been raised for the greater occurrence of wind pollination in some habitats and towards higher latitudes. To date, however, there has been no comprehensive global investigation of these hypotheses. Aims: Investigating a range of hypotheses for the role of biotic and abiotic factors as determinants of the global variation in animal versus wind pollination. Methods: We analysed 67 plant communities ranging from 70º North to 34º South. For these we determined habitat type, species richness, insularity, topographic heterogeneity, current climate and Late-Quaternary climate change. The predictive effects of these factors on the proportion of wind- and animal-pollinated plants were tested using correlations, ordinary least squares (OLS) and logistic regression analyses with information-theoretic model selection. Results: The proportion of animal-pollinated plant species was positively associated with plant species richness and current temperature. Furthermore, in forest, animal pollination was positively related to precipitation. Historical climate was only weakly and idiosyncratically correlated with animal pollination. Conclusion: Results were consistent with the hypothesised reduced chance for wind-transported pollen reaching conspecific flowers in species-rich communities, fewer constraints on nectar production in warm and wet habitats, and reduced relative effectiveness of wind dispersal in humid areas. There was little evidence of a legacy of historical climate change affecting these patterns

    How can agent based modelling provide new insights into the impact of minimum unit pricing in Scotland?

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    In recent years we have gained insight into the impact of minimum unit pricing (MUP)—a legal floor price below which a given volume of alcohol cannot be sold—on population-level reductions in alcohol sales, consumption and harm. However, several questions remain unanswered including how individual-level purchasing changes impact the local economy (e.g., balance between on-licence and off-licence outlets), lead to long-term population-level trends (e.g., youth drinking) and social harms (e.g., violence). Agent-based modelling captures heterogeneity, emergence, feedback loops and adaptive and dynamic features, which provides an opportunity to understand the nuanced effects of MUP. Agent-based models (ABM) simulate heterogeneous agents (e.g., individuals, organisations) often situated in space and time that interact with other agents and/or with their environment, allowing us to identify the mechanisms underlying social phenomena. ABMs are particularly useful for theory development, and testing and simulating the impacts of policies and interventions. We illustrate how ABMs could be applied to generate novel insights and provide best estimates of social network effects, and changes in purchasing behaviour and social harms, due to the implementation of MUP. ABMs like other modelling approaches can simulate alternative implementations of MUP (e.g., policy intensity [£0.50, £0.60] or spatial scales [local, national]) but can also provide an understanding of the potential impact of MUP on different population groups (e.g., alcohol exposure of young people who are not yet drinking). Using ABMs to understand the impact of MUP would provide new insights to complement those from traditional epidemiological and other modelling methods

    Engaging with assessment: increasing student engagement through continuous assessment

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    Student engagement is intrinsically linked to two important metrics in learning: student satisfaction and the quality of the student experience. One of the ways that engagement can be influenced is through careful curriculum design. Using the knowledge that many students are ‘assessment-driven’ a low stakes continuous weekly summative e-assessment was introduced to a module. The impact this had on student engagement was measured by studying student activity within the module virtual learning environment (VLE). It was found that introduction of the e-assessments led to a significant increase in VLE activity compared to the VLE activity in that module the previous year, and also compared to the VLE activity of two other modules studied by the same student cohort. As many institutions move towards greater blended or online deliveries it will become more important to ensure that VLEs encourage high levels of student engagement in order to maintain or enhance the student experience. Keywords : continuous assessment, learning analytics, student engagement, virtual learning environment

    Post-little ice age glacial geomorphology of contrasting topographic settings at Skálafellsjökull, southeast Iceland

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    Glacial geomorphological mapping from the southern margin of Skálafellsjökull, southeast Iceland, depicts a topographically diverse mountainside, influencing glacier dynamics, landform formation and glacier retreat since the Little Ice Age maximum in ∼1890. The glacial landforms present are typical of southeast Icelandic temperate glaciers, comprising recessional push moraines, including sawtooth moraines, and associated fluting. Study area A demonstrates an abandoned lobe confined by steep V-shaped topography, displaying moraines and minimal fluting, suggesting low preservation of landforms, and changes in glacier behaviour. At study area B, the sawtooth moraine morphology demonstrates changes in the glacier margin as the ice interacted with a series of topographic benches during active recession. The steep-sided valley at study area C illustrates densely spaced arcuate moraines, reflecting subtle changes in ice elevation. This mapping provides a framework for further investigations into glacier retreat rates and the influence of local topography and climate
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