5,429 research outputs found

    Collaborative Growth Toward Discovery: Becoming Stronger through Change

    Get PDF
    The radical act of replacing a traditional OPAC and ILS with a hosted library services platform (LSP) and web-scale discovery (WSD) system creates the impetus for libraries to rethink core workflows and practices. Both of these tools have the potential to greatly improve access to library collections and enhance user experience, but only if the implementation is a collaborative effort between different stakeholders, technical experts and subject librarians, grounded in a thoughtful selection process that emphasizes user needs. Furthermore, because this model removes the traditional OPAC, subject librarians must take on the challenge of understanding the tool and work as partners with backend technical experts as well as the vendor so that they are not left out of providing research assistance as algorithms replace some traditional library skills. Grounded in the literature of collaborative learning and librarian attitudes towards discovery systems, this chapter describe the process of creating a culture of collaboration centered on user needs. Such a model is central to the process of evaluation and implementation of a LSP and a WSD service, particularly in the context of a university with multiple campuses and diverse users. We established a well-structured collaboration model from the systems evaluation phase, and continued to apply the model to the implementation phase. In 2010, the initial solution was to keep a traditional OPAC, and implement WorldCat Local as article discovery tool while doing in-depth user studies and gathering feedback from subject librarians to create a data-driven decision making habit. In 2014, we determined that Alma and Primo should replace the current Voyager ILS and WorldCat Local. The implementation process started in January 2015 and will go live in July 2015. The chapter will share the journey of creating a collaborative model and implementing unified resource management and discovery

    Continuous Ordinal Regression for Analysis of Visual Analogue Scales: The R Package ordinalCont

    Get PDF
    This paper introduces the R package ordinalCont, which implements an ordinal regression framework for response variables which are recorded on a visual analogue scale (VAS). This scale is used when recording subjects' perception of an intangible quantity such as pain, anxiety or quality of life, and consists of a mark made on a linear scale. We implement continuous ordinal regression models for VAS as the appropriate method of analysis for such responses, and introduce smoothing terms and random effects in the linear predictor. The model parameters are estimated using constrained optimization of the penalized likelihood and the penalty parameters are automatically selected via maximization of their marginal likelihood. The estimation algorithm is shown to perform well, in a simulation study. Two examples of application are given: the first involves the analysis of pain outcomes in a clinical trial for laser treatment for chronic neck pain; the second is an analysis of quality of life outcomes in a clinical trial for chemotherapy for the treatment of breast cancer

    Spin Transfers for Baryon Production in Polarized pp Collisions at RHIC-BNL

    Get PDF
    We consider the inclusive production of longitudinally polarized baryons in pp{\vec p}p collisions at RHIC-BNL, with one longitudinally polarized proton. We study the spin transfer between the initial proton and the produced baryon as a function of its rapidity and we elucidate its sensitivity to the quark helicity distributions of the proton and to the polarized fragmentation functions of the quark into the baryon. We make predictions using an SU(6) quark spectator model and a perturbative QCD (pQCD) based model. We discuss these different predictions, and what can be learned from them, in view of the forthcoming experiments at RHIC-BNL.Comment: 28 pages, 11 figure

    Point-of-Care Ultrasound Assessment of Tropical Infectious Diseases—A Review of Applications and Perspectives

    Get PDF
    The development of good quality and affordable ultrasound machines has led to the establishment and implementation of numerous point-of-care ultrasound (POCUS) protocols in various medical disciplines. POCUS for major infectious diseases endemic in tropical regions has received less attention, despite its likely even more pronounced benefit for populations with limited access to imaging infrastructure. Focused assessment with sonography for HIV-associated TB (FASH) and echinococcosis (FASE) are the only two POCUS protocols for tropical infectious diseases, which have been formally investigated and which have been implemented in routine patient care today. This review collates the available evidence for FASH and FASE, and discusses sonographic experiences reported for urinary and intestinal schistosomiasis, lymphatic filariasis, viral hemorrhagic fevers, amebic liver abscess, and visceral leishmaniasis. Potential POCUS protocols are suggested and technical as well as training aspects in the context of resource-limited settings are reviewed. Using the focused approach for tropical infectious diseases will make ultrasound diagnosis available to patients who would otherwise have very limited or no access to medical imaging

    Unexpected features of branched flow through high-mobility two-dimensional electron gases

    Full text link
    GaAs-based two-dimensional electron gases (2DEGs) show a wealth of remarkable electronic states, and serve as the basis for fast transistors, research on electrons in nanostructures, and prototypes of quantum-computing schemes. All these uses depend on the extremely low levels of disorder in GaAs 2DEGs, with low-temperature mean free paths ranging from microns to hundreds of microns. Here we study how disorder affects the spatial structure of electron transport by imaging electron flow in three different GaAs/AlGaAs 2DEGs, whose mobilities range over an order of magnitude. As expected, electrons flow along narrow branches that we find remain straight over a distance roughly proportional to the mean free path. We also observe two unanticipated phenomena in high-mobility samples. In our highest-mobility sample we observe an almost complete absence of sharp impurity or defect scattering, indicated by the complete suppression of quantum coherent interference fringes. Also, branched flow through the chaotic potential of a high-mobility sample remains stable to significant changes to the initial conditions of injected electrons.Comment: 22 pages, 4 figures, 1 tabl

    Production of four-quark states with double heavy quarks at LHC

    Full text link
    We study the hadronic production of four-quark states with double heavy quarks and double light antiquarks at LHC. The production mechanism is that a color anti-triplet diquark cluster consisting of double heavy quarks is formed first from the produced double heavy quark-antiquark pairs via gggg fusion hard process, followed by the fragmentation of the diquark cluster into a four-quark (tetraquark) state. Predictions for the production cross sections and their differential distributions are presented. Our results show that it is quite promising to discover these tetraquark states in LHC experiments both for large number events and for their unique signatures in detectors.Comment: 17 pages,8 figure

    Evidence for SU(3) symmetry breaking from hyperon production

    Get PDF
    We examine the SU(3) symmetry breaking in hyperon semileptonic decays (HSD) by considering two typical sets of quark contributions to the spin content of the octet baryons: Set-1 with SU(3) flavor symmetry and Set-2 with SU(3) flavor symmetry breaking in HSD. The quark distributions of the octet baryons are calculated with a successful statistical model. Using an approximate relation between the quark fragmentation functions and the quark distributions, we predict polarizations of the octet baryons produced in e+ee^+e^- annihilation and semi-inclusive deeply lepton-nucleon scattering in order to reveal the SU(3) symmetry breaking effect on the spin structure of the octet baryons. We find that the SU(3) symmetry breaking significantly affects the hyperon polarization. The available experimental data on the Λ\Lambda polarization seem to favor the theoretical predictions with SU(3) symmetry breaking. We conclude that there is a possibility to get a collateral evidence for SU(3) symmetry breaking from hyperon production. The theoretical errors for our predictions are discussed.Comment: 3 tables, 14 figure
    corecore