400 research outputs found

    The Food of Pond Fish in Northern Utah

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    A series of ponds in northern Utah supplied mainly by artesian water was poisoned with rotenone during 1949-1950

    Rethinking the Freshwater Eel: Salt Marsh Trophic Support of the American Eel, Anguilla rostrata

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    Despite the fact that Anguilla rostrata (American eel) are frequently captured in salt marshes, their role in salt marsh food webs and the influence of human impacts, such as tidal restrictions, on this role remains unclear. To better understand salt marsh trophic support of A. rostrata, eels were collected from tidally restricted and unrestricted salt marsh creeks within three New England estuaries. Gut contents were examined, and eel muscle tissue was analyzed for carbon and nitrogen stable isotope values and entered into MixSir mixing models to understand if salt marsh food sources are important contributors to eel diet. Data suggest that eel prey rely heavily on salt marsh organic matter and eels utilize salt marsh secondary production as an energetic resource over time, and thus can be considered salt marsh residents. Gut contents indicate that A. rostrata function as top predators, feeding primarily on secondary consumers including other fish species, crustaceans, and polychaetes. Higher A. rostrata trophic position measured upstream of reference creeks suggests that severe tidal restrictions may result in altered food webs, but it is not clear how this impacts the overall fitness of A. rostrata populations in New England salt marshes.University of New Hampshire. Sea Grant ProgramUniversity of New Hampshire. Marine Program (William R. Spaulding Endowment

    Two Pfam protein families characterized by a crystal structure of protein lpg2210 from Legionella pneumophila.

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    BackgroundEvery genome contains a large number of uncharacterized proteins that may encode entirely novel biological systems. Many of these uncharacterized proteins fall into related sequence families. By applying sequence and structural analysis we hope to provide insight into novel biology.ResultsWe analyze a previously uncharacterized Pfam protein family called DUF4424 [Pfam:PF14415]. The recently solved three-dimensional structure of the protein lpg2210 from Legionella pneumophila provides the first structural information pertaining to this family. This protein additionally includes the first representative structure of another Pfam family called the YARHG domain [Pfam:PF13308]. The Pfam family DUF4424 adopts a 19-stranded beta-sandwich fold that shows similarity to the N-terminal domain of leukotriene A-4 hydrolase. The YARHG domain forms an all-helical domain at the C-terminus. Structure analysis allows us to recognize distant similarities between the DUF4424 domain and individual domains of M1 aminopeptidases and tricorn proteases, which form massive proteasome-like capsids in both archaea and bacteria.ConclusionsBased on our analyses we hypothesize that the DUF4424 domain may have a role in forming large, multi-component enzyme complexes. We suggest that the YARGH domain may play a role in binding a moiety in proximity with peptidoglycan, such as a hydrophobic outer membrane lipid or lipopolysaccharide

    Peer Supportersā€™ Mental Health and Emotional Wellbeing needs:Key Factors and Opportunities for Co-Produced Training

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    Abstract Introduction Peer supporters are a valuable asset to mental health and support services, but their own mental health needs are often overlooked in research and practice. This study explored peer supporters'Ā perceived challenges of maintaining their mental health and emotional wellbeing and coā€produced training needs. Methods A qualitative approach was used to explore factors affecting peer supporters' mental health and emotional wellbeing. Semiā€structured interviews and focus groups were conducted online with 11 peer supporters across North East England. Results A thematic analysis identified: ā€˜Lack of training and supportā€™, ā€˜Role ambiguityā€™Ā and ā€˜Emotional labourā€™ as challenges experienced by peer supporters in relation to maintaining their mental health and emotional wellbeing. Peer supporters' own lived experiences had the potential to act as a barrier towards providing support to others. Conflict with peer ā€˜supporteesā€™ sometimes negatively impacted on the peer supporter experience. Participant responses emphasised a need for personā€centred, coā€produced training. Conclusion This work highlights the need for targeted training for peer supporters, including both roleā€specific education and strategies to support their mental health and emotional wellbeing. Patient or Public Contribution Participants were contacted and asked to provide feedback on finalised themes to ensure the analysis was congruent with their experiences, further enabling the future development of an emotional wellbeing training programme for peer supporters

    Presolar Grains from Novae: Evidence from Neon and Helium Isotopes in Comet Dust Collections

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    Presolar grains in meteorites and interplanetary dust particles (IDPs) carry non-solar isotopic signatures pointing to origins in supernovae, giant stars, and possibly other stellar sources. There have been suggestions that some of these grains condensed in the ejecta of classical nova outbursts, but the evidence is ambiguous. We report neon and helium compositions in particles captured on stratospheric collectors flown to sample materials from comets 26P/Grigg-Skjellerup and 55P/Tempel-Tuttle that point to condensation of their gas carriers in the ejecta of a neon (ONe) nova. The absence of detectable 3He in these particles indicates space exposure to solar wind (SW) irradiation of a few decades at most, consistent with origins in cometary dust streams. Measured 4He/20Ne, 20Ne/22Ne, 21Ne/22Ne and 20Ne/21Ne isotope ratios, and a low upper limit on 3He/4He, are in accord with calculations of nucleosynthesis in neon nova outbursts. Of these, the uniquely low 4He/20Ne and high 20Ne/22Ne ratios are the most diagnostic, reflecting the large predicted 20Ne abundances in the ejecta of such novae. The correspondence of measured Ne and He compositions in cometary matter with theoretical predictions is evidence for the presence of presolar grains from novae in the early solar system.Comment: As appeared in the Astrophysical Journa
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