2,226 research outputs found

    Striving for Uniqueness: Data-Driven Database Deselection

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    As libraries endure an ongoing crisis of available funds to meet inflating electronic content costs, the idea to dispatch the perceived least important e-resources to help balance the budget is a tempting solution. Mercer University Libraries recognizes the challenge of finding areas in which to cut back on its resources. They closely examine their subscriptions to prioritize their patrons’ needs, maintain budgetary equilibrium, and remain true to their goals. The Library Systems Department has worked to develop their own tool to assist decision makers with pertinent information about the uniqueness of both their full text and index databases and packages, both to save money and to improve their programming skills. This paper highlights their approach to this tool and the effects it has had so far

    Wrangle Your Data Like a Pro With the Data Processing Power of Python

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    Management, delivery, and marketing of library resources and collections necessitate interaction with a plethora of data from many sources and in many forms. Accessing and transforming data into meaningful information or different formats used in library automation can be time consuming, but a working knowledge of a programming language can improve efficiency in many facets of librarianship. From processing lists to creating extensible markup language (XML), from editing machine-readable cataloging (MARC) records before upload to automating statistical reports, the Python programming language and third-party application programming interfaces (APIs) can be used to accomplish both behind-the-scenes tasks and end-user facing projects. Creating programmatic solutions to problems requires an understanding of potential. Here we summarize the data sources, flows, and transformations used to accomplish existing projects at Mercer University and the College of Charleston. Foundational programming techniques are explained and resources for learning Python are shared

    Status, Testosterone, and Human Intellectual Performance: Stereotype Threat as Status Concern

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    Results from two experiments suggest that stereotype-threat effects are special cases of a more general process involving the need to maintain or enhance status. We hypothesized that situations capable of confirming a performance stereotype might represent either a threat to status or an opportunity for enhancement of status, depending on the nature of the stereotype. The positive relationship between baseline testosterone and status sensitivity led us to hypothesize that high testosterone levels in males and females would amplify existing performance expectations when gender-based math-performance stereotypes were activated. In Study 1, high-testosterone females performed poorly on a math test when a negative performance stereotype was primed. In Study 2, high-testosterone males excelled on a math test when a positive performance stereotype was primed. The moderating effect of testosterone on performance suggests that a stereotype-relevant situation is capable of conferring either a loss or a gain of status on targets of the stereotype.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

    System-L amino acid transporters play a key role in pancreatic b-cell signalling and function

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    The branched-chain amino acids (BCAA) leucine, isoleucine and valine, are essential amino acids that play a critical role in cellular signalling and metabolism. They acutely stimulate insulin secretion and activate the regulatory serine/threonine kinase mammalian target of rapamycin complex 1 (mTORC1), a kinase that promotes increased β-cell mass and function. The effects of BCAA on cellular function are dependent on their active transport into mammalian cells via amino acid transporters and thus the expression and activity of these transporters likely influences β-cell signalling and function. In this report we show that the System-L transporters are required for BCAA uptake into clonal β-cell lines and pancreatic islets and that these are essential for signalling to mTORC1. Further investigation revealed that the System-L transporter LAT1 is abundantly expressed in islets and that knock-down of LAT1 using siRNA inhibits mTORC1 signalling, leucine-stimulated insulin secretion and islet cell proliferation. In summary, we show that the System-L transporter LAT1 is required for regulating β-cell signaling and function in islets and thus may be a novel pharmacological/nutritional target for the treatment and prevention of type-2 diabetes

    An HP1 isoform-specific feedback mechanism regulates Suv39h1 activity under stress conditions.

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    The presence of H3K9me3 and heterochromatin protein 1 (HP1) are hallmarks of heterochromatin conserved in eukaryotes. The spreading and maintenance of H3K9me3 is effected by the functional interplay between the H3K9me3-specific histone methyltransferase Suv39h1 and HP1. This interplay is complex in mammals because the three HP1 isoforms, HP1α, β, and γ, are thought to play a redundant role in Suv39h1-dependent deposition of H3K9me3 in pericentric heterochromatin (PCH). Here, we demonstrate that despite this redundancy, HP1α and, to a lesser extent, HP1γ have a closer functional link to Suv39h1, compared to HP1β. HP1α and γ preferentially interact in vivo with Suv39h1, regulate its dynamics in heterochromatin, and increase Suv39h1 protein stability through an inhibition of MDM2-dependent Suv39h1-K87 polyubiquitination. The reverse is also observed, where Suv39h1 increases HP1α stability compared HP1β and γ. The interplay between Suv39h1 and HP1 isoforms appears to be relevant under genotoxic stress. Specifically, loss of HP1α and γ isoforms inhibits the upregulation of Suv39h1 and H3K9me3 that is observed under stress conditions. Reciprocally, Suv39h1 deficiency abrogates stress-dependent upregulation of HP1α and γ,  and enhances HP1β levels. Our work defines a specific role for HP1 isoforms in regulating Suv39h1 function under stress via a feedback mechanism that likely regulates heterochromatin formation

    Catalyst stabilization by stoichiometrically limited layer-by-layer overcoating in liquid media

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    The use of metal oxide overcoats over supported nanoparticle catalysts has recently led to impressive improvements in catalyst stability and selectivity. The deposition of alumina is especially important for renewable catalysis due to its robustness in liquid-phase conditions. However, there are limited reports of work on alumina deposition and stabilization that goes beyond atomic layer deposition (ALD). Here, we present a layer-by-layer deposition technique for the controlled formation of conformal alumina overcoats in the liquid phase. This technique is easy to perform in common wet chemistry conditions. Alternated exposure of the substrate to stoichiometric amounts of aluminum alkoxide and water in liquid-phase conditions leads to the formation of a porous overcoat that was easily tunable by varying synthesis parameters. The deposition of 60 Al2O3 layers onto Al2O3-supported copper nanoparticles suppressed irreversible deactivation during the liquid-phase hydrogenation of furfural – a key biomass-derived platform molecule. The porous overcoat leads to highly accessible metal sites, which significantly reduces the partial site blocking observed in equivalent overcoats formed by ALD. We suggest that the ease of scalability and the high degree of control over the overcoat’s properties during liquid-phase synthesis could facilitate the development of new catalyst overcoating applications

    Insights Into the Effects of Mucosal Epithelial and Innate Immune Dysfunction in Older People on Host Interactions With Streptococcus pneumoniae

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    In humans, nasopharyngeal carriage of Streptococcus pneumoniae is common and although primarily asymptomatic, is a pre-requisite for pneumonia and invasive pneumococcal disease (IPD). Together, these kill over 500,000 people over the age of 70 years worldwide every year. Pneumococcal conjugate vaccines have been largely successful in reducing IPD in young children and have had considerable indirect impact in protection of older people in industrialized country settings (herd immunity). However, serotype replacement continues to threaten vulnerable populations, particularly older people in whom direct vaccine efficacy is reduced. The early control of pneumococcal colonization at the mucosal surface is mediated through a complex array of epithelial and innate immune cell interactions. Older people often display a state of chronic inflammation, which is associated with an increased mortality risk and has been termed ‘Inflammageing’. In this review, we discuss the contribution of an altered microbiome, the impact of inflammageing on human epithelial and innate immunity to S. pneumoniae, and how the resulting dysregulation may affect the outcome of pneumococcal infection in older individuals. We describe the impact of the pneumococcal vaccine and highlight potential research approaches which may improve our understanding of respiratory mucosal immunity during pneumococcal colonization in older individuals
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