2,216 research outputs found

    Travelling to succeed: introducing a library travel bursary scheme

    Get PDF
    The University of Exeter Library Travel Bursaries Scheme was established in 2012 to support students who wish to visit other libraries and / or archives in order to further their studies. We award up to £200 to taught students who are undertaking or are about to undertake their final year dissertations or projects. Students can claim for travel, accommodation and access fee expenditure. Following a successful pilot year in 2012–13, the scheme has proved popular again in 2013–14 and we plan to continue this valuable opportunity for our students

    Sperm morphology and the evolution of intracellular sperm-egg interactions

    Get PDF
    This is the final version of the article. Available from Wiley via the DOI in this record.Sperm morphology is incredibly diverse, even among closely related species, yet the coevolution between males and females of fertilization recognition systems is necessary for successful karyogamy (male and female pronuclear fusion). In most species, the entire sperm enters the egg during fertilization so sperm morphological diversity may impact the intracellular sperm–egg interactions necessary for karyogamy. We quantified morphological variation of sperm inside eggs prior to and following karyogamy in several species of Drosophila to understand whether evolution of sperm morphology could influence intracellular sperm–egg interactions (ISEIs). We measured seven parameters that describe ISEIs among species to determine whether these parameters varied both within a species across development and across species at the same developmental stage. We used heterospecific crosses to test the relative role of male origin, female origin, and interaction between the male and female in determining ISEIs. We found that sperm shape changed within a species as development proceeded and, at particular development stages, species varied in some ISEIs. Parental origin had an effect on some ISEIs, with a general trend for a stronger female effect. Overall, our findings identify conserved and variable ISEIs among species and demonstrate the potential to contribute understanding to gamete evolution and development.Leverhulme Trus

    Recommendation report for the implementation of research data management policy and for a sustainable research data management service at the University of Exeter

    Get PDF
    This is the Open Access and Research Data Management Policy Task and Finish Group's recommendation report for the implementation of research data management policy and a sustainable research data management service at the University of Exeter.JIS

    Sustaining tropical timber trees in production forests of Asia - ensuring their genetic viability

    Get PDF
    Sustainable timber production in approximately 400 million hectares of production forests in the tropics would be enhanced by incorporating genetic conservation measures in their management. This factsheet, based on a scientific review, explains why tropical Asian timber species are particularly vulnerable to logging and habitat fragmentation and what policymakers and forest managers can do to maintain productivity and resilience of timber trees in Asian production forests

    Electrodeposition and Capacitive Behavior of Films for Electrodes of Electrochemical Supercapacitors

    Get PDF
    Polypyrrole films were deposited by anodic electropolymerization on stainless steel substrates from aqueous pyrrole solutions containing sodium salicylate and tiron additives. The deposition yield was studied under galvanostatic conditions. The amount of the deposited material was varied by the variation of deposition time at a constant current density. SEM studies showed the formation of porous films with thicknesses in the range of 0–3 μm. Cyclic voltammetry data for the films tested in 0.5 M Na2SO4 solutions showed capacitive behavior and high specific capacitance (SC) in a voltage window of 0.9 V. The films prepared from pyrrole solutions containing tiron showed better capacitive behavior compared to the films prepared from the solutions containing sodium salicylate. A highest SC of 254 F g−1 was observed for the sample with a specific mass of 89 μg cm−2 at a scan rate of 2 mV s−1. The SC decreased with an increasing film thickness and scan rate. The results indicated that the polypyrrole films deposited on the stainless steel substrates by anodic electropolymerization can be used as electrodes for electrochemical supercapacitors (ES)

    Preparation of anti-vicinal amino alcohols: asymmetric synthesis of D-erythro-Sphinganine, (+)-spisulosine and D-ribo-phytosphingosine

    Get PDF
    Two variations of the Overman rearrangement have been developed for the highly selective synthesis of anti-vicinal amino alcohol natural products. A MOM-ether directed palladium(II)-catalyzed rearrangement of an allylic trichloroacetimidate was used as the key step for the preparation of the protein kinase C inhibitor D-erythro-sphinganine and the antitumor agent (+)-spisulosine, while the Overman rearrangement of chiral allylic trichloroacetimidates generated by asymmetric reduction of an alpha,beta-unsaturated methyl ketone allowed rapid access to both D-ribo-phytosphingosine and L-arabino-phytosphingosine

    Rationale and recommendations on decolonising the pedagogy and curriculum of the Law School at the University of Exeter

    Get PDF
    This report outlines the rationale behind and recommendations on the steps that need to be taken towards decolonising the Law School's pedagogy and curriculum. The reason is that we see decolonisation as not something that can be achieved but as an ongoing process. It concludes a two-year process of research and discussions involving a joint effort between staff and students. A rationale for a change in approach to both pedagogy and curriculum is presented together with recommendations and practical examples of how this might be achieved in modular teaching in the Law School

    Intra-specific variation of sperm length in the malaria vector Anopheles gambiae: males with shorter sperm have higher reproductive success

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Intra-specific variation in sperm length influences male reproductive success in several species of insects. In males of the malaria vector <it>Anopheles gambiae</it>, sperm length is highly variable but the significance of this variation is unknown. Understanding what determines the reproductive success of male mosquitoes is critical for controlling malaria, and in particular for replacing natural populations with transgenic, malaria-resistant mosquitoes.</p> <p>Methods</p> <p>A laboratory population of <it>A. gambiae </it>males was tested for intra-specific variation in sperm length. A full-sib quantitative genetic design was used to test for a genetic component of sperm length in <it>A. gambiae </it>males and estimate its heritability. This study also tested for a relationship between sperm length and male reproductive success in <it>A. gambiae</it>. Male reproductive success was measured as the proportions of inseminated and ovipositing females.</p> <p>Results</p> <p>There was intra-specific variation of sperm length in <it>A. gambiae</it>. There was no significant genetic variation in sperm length and its heritability was low (h<sup>2 </sup>= 0.18) compared to other insects. Sperm length was correlated with male body size (measured as wing length). Males with short sperm had significantly higher reproductive success than males with long sperm and this was independent of body size.</p> <p>Conclusion</p> <p>This is the first study to demonstrate intra-specific variation in sperm length in <it>A. gambiae </it>and that males with short sperm have higher reproductive success. That sperm length influences female oviposition is important for any strategy considering the release of transgenic males.</p
    • …
    corecore