1,057 research outputs found

    Microstructure-property relationships in Al-Cu-Li-Ag-Mg Weldalite (tm) alloys, part 2

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    The microstructure and mechanical properties of the ultrahigh strength Al-Cu-Li-Ag-Mg alloy, Weldalite (tm) 049, were studied. Specifically, the microstructural features along with tensile strength, weldability, Young's modulus and fracture toughness were studied for Weldalite (tm) 049 type alloys with Li contents ranging from 1.3 to 1.9 wt. pct. The tensile properties of Weldalite 049 and Weldalite 049 reinforced with TiB2 particles fabricated using the XD (tm) process were also evaluated at cryogenic, room, and elevated temperatures. In addition, an experimental alloy, similar in composition to Weldalite 049 but without the Ag+Mg, was fabricated. The microstructure of this alloy was compared with that of Weldalite 049 in the T6 condition to assess the effect of Ag+Mg on nucleation of strengthening phases in the absence of cold work

    Synchronous collaborative information retrieval: techniques and evaluation

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    Synchronous Collaborative Information Retrieval refers to systems that support multiple users searching together at the same time in order to satisfy a shared information need. To date most SCIR systems have focussed on providing various awareness tools in order to enable collaborating users to coordinate the search task. However, requiring users to both search and coordinate the group activity may prove too demanding. On the other hand without effective coordination policies the group search may not be effective. In this paper we propose and evaluate novel system-mediated techniques for coordinating a group search. These techniques allow for an effective division of labour across the group whereby each group member can explore a subset of the search space.We also propose and evaluate techniques to support automated sharing of knowledge across searchers in SCIR, through novel collaborative and complementary relevance feedback techniques. In order to evaluate these techniques, we propose a framework for SCIR evaluation based on simulations. To populate these simulations we extract data from TREC interactive search logs. This work represent the first simulations of SCIR to date and the first such use of this TREC data

    The emergence of an American, capitalist ecclesiology in the independent Christian churches: an analysis of how the Stone-Campbell restoration movement created a new theological tradition based on Scottish common sense philosophy

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    This thesis identifies and describes the fundamental theological positions of the Independent Christian Churches, one of three main branches of the Stone-Campbell Restoration Movement, an upstart church that had its beginnings on the American frontier in the early nineteenth century. The Independent Christian Churches theology is dependent upon the particular hermeneutic method developed by the Movement's founders and this thesis explores the implications of the Independent Christian Churches hermeneutic. This hermeneutic is based on the epistemological assumptions of the philosophy of Scottish Common Sense Realism, and the theological positions of the Independent Christian Churches is a result of the amalgamation of this Common Sense hermeneutic, the experience of the Stone-Campbell Movement with the antebellum American landscape, the adaptation of core American values (individualism, equality, and freedom), the adoption of the widespread American expectation of a millennial dawn, and the embrace of American capitalism. The leaders of the Restoration Movement believed that they were not engaged in theological speculation, but were simply proclaiming the clear teaching of the "Bible alone". The result of this disregard of theology is that Independents produce few formal works of theology as such, and Independent theology is primarily advanced through histories of the Restoration Movement and through the developing beliefs and practices of an individual congregation. This thesis deals with the development of Independent Christian Churches theology from its inception in the early nineteenth century to the present day. In the theological formulations of the Independent Christian Churches, theology is subsumed under other discourses and, while theological language is retained, such language is actually a facade for the epistemology of Scottish Common Sense Realism, American ideals of individualism, equality, and freedom, and capitalist economics. As the intellectual foundations that undergird the Scottish Common Sense hermeneutic fragmented and the experience of the American frontier faded away, they left behind the theological formulations created in response to this philosophy and to this experience, leaving the impression among adherents of the Independent Christian Churches that their religion was actually based on "the Bible alone". Without recourse to either of these narratives, capitalist economics has provided a new metanarrative for the Independent Christian Churches which offers new options for faith and practice. Under the circumstances that the Independent Christian Churches have created for theological discourse, where the continuities with Christian history and Christian theology have been sundered, theology is dependent on secular discourses in order to proceed. Therefore, this is an interdisciplinary investigation that draws upon the discourses of theology, philosophy, hermeneutics, history, sociology, and economics; fundamentally its concern is theological, and it is more specifically concerned with ecclesiology.

    Multivalent antigen arrays exhibit high avidity binding and modulation of B cell receptor-mediated signaling to drive efficacy against experimental autoimmune encephalomyelitis

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    This document is the Accepted Manuscript version of a Published Work that appeared in final form in Biomacromolecules, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.biomac.7b00335.A pressing need exists for antigen-specific immunotherapies (ASIT) that induce selective tolerance in autoimmune disease while avoiding deleterious global immunosuppression. Multivalent soluble antigen arrays (SAgAPLP:LABL), consisting of a hyaluronic acid (HA) linear polymer backbone co-grafted with multiple copies of autoantigen (PLP) and cell adhesion inhibitor (LABL) peptides, are designed to induce tolerance to a specific multiple sclerosis (MS) autoantigen. Previous studies established that hydrolyzable SAgAPLP:LABL, employing a degradable linker to codeliver PLP and LABL, was therapeutic in experimental autoimmune encephalomyelitis (EAE) in vivo and exhibited antigen-specific binding with B cells, targeted the B cell receptor (BCR), and dampened BCR-mediated signaling in vitro. Our results pointed to sustained BCR engagement as the SAgAPLP:LABL therapeutic mechanism, so we developed a new version of the SAgA molecule using non-hydrolyzable conjugation chemistry, hypothesizing it would enhance and maintain the molecule’s action at the cell surface to improve efficacy. ‘Click SAgA’ (cSAgAPLP:LABL) uses hydrolytically stable covalent conjugation chemistry (Copper-catalyzed Azide-Alkyne Cycloaddition (CuAAC)) rather than a hydrolyzable oxime bond to attach PLP and LABL to HA. We explored cSAgAPLP:LABL B cell engagement and modulation of BCR-mediated signaling in vitro through flow cytometry binding and calcium flux signaling assays. Indeed, cSAgAPLP:LABL exhibited higher avidity B cell binding and greater dampening of BCR-mediated signaling than hydrolyzable SAgAPLP:LABL. Furthermore, c SAgAPLP:LABL exhibited significantly enhanced in vivo efficacy compared to hydrolyzable SAgAPLP:LABL, achieving equivalent efficacy at one quarter of the dose. These results indicate that non-hydrolyzable conjugation increased the avidity of cSAgAPLP:LABL to drive in vivo efficacy through modulated BCR-mediated signaling.NIH T32 GM008545Madison and Lila Self Graduate Fellowship at the University of KansasHoward Rytting pre-doctoral fellowship from the Department of Pharmaceutical Chemistry at the University of Kansa

    Whose expertise is it? Evidence for autistic adults as critical autism experts

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    This is the final version. Available on open access from Frontiers Media via the DOI in this recordAutistic and non-autistic adults' agreement with scientific knowledge about autism, how they define autism, and their endorsement of stigmatizing conceptions of autism has not previously been examined. Using an online survey, we assessed autism knowledge and stigma among 636 adults with varied relationships to autism, including autistic people and nuclear family members. Autistic participants exhibited more scientifically based knowledge than others. They were more likely to describe autism experientially or as a neutral difference, and more often opposed the medical model. Autistic participants and family members reported lower stigma. Greater endorsement of the importance of normalizing autistic people was associated with heightened stigma. Findings suggest that autistic adults should be considered autism experts and involved as partners in autism research.Professional Staff CongressCity University of New Yor

    Ultrasonic Phased-Array Characterization for NDE Applications

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    Southwest Research Institute (SwRI) recently fabricated and delivered the 100-channel Ultrasonic Phased-Array Testbed System (UPATS) for NASA's Langley Research Center. NASA prepared the specifications and provided the funding to develop UPATS in order to provide a tool for the improvement of ultrasonic nondestructive evaluation (NDE) and characterization of materials. UPATS incorporates state-of-the-art phased-array concepts such as beam steering, focusing, apodization, and phase-sensitive detection which make it possible to develop more sophisticated testing methodologies. It also can be used to investigate fundamental ultrasonic propagation and detection phenomena such as refraction, diffraction, scattering, and beam broadening

    Role of dopamine in dorsal medial prefrontal cortex in yohimbine-induced reinstatement of food seeking in rats

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    In humans, relapse to maladaptive eating habits during dieting is often provoked by stress.Weadapted a drug relapse-reinstatement model to study the role of stress in relapse to food seeking (Nair et al., Prog. Neurobiol., 2009). In our model, the anxiogenic drug yohimbine, an alpha-2 adrenoceptor antagonist, that causes stress-like responses in humans and laboratory animals, reliably reinstates food seeking.Werecently found that yohimbine-induced reinstatement of food seeking is attenuated by systemic injections of SCH23390 (a D1-family receptor antagonist) but not clonidine (an alpha-2 adrenoceptor agonist). Here, we studied the role of the medial prefrontal cortex (mPFC) in yohimbine-induced reinstatement. We trained food-restricted rats to lever-press for 35% high-fat pellets every other day (9–15 3 h sessions). We then extinguished the food-reinforced operant responding for 10–14 days by removing the pellets. Subsequently, we tested the effect of systemic injections of yohimbine (0, 2 mg/kg) on reinstatement of food seeking. In Exp. 1we found that yohimbine-induced reinstatement was associated with strong induction of Fos (a marker of neuronal activity) in the dorsal mPFC and weaker Fos induction in the ventral mPFC. In Exp. 2 we found that dorsal but not ventral mPFC injections of the D1-family receptor antagonist SCH23390 (0.5, 1.0g/side) decreased yohimbine-induced reinstatement of food seeking. Our data indicate a critical role of dorsal mPFC dopamine in reinstatement food seeking induced by the pharmacological stressor yohimbine
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