5,017 research outputs found

    Formulating MEDLINE queries for article retrieval based on PubMed exemplars

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    Bibliographic search engines allow endless possibilities for building queries based on specific words or phrases in article titles and abstracts, indexing terms, and other attributes. Unfortunately, deciding which attributes to use in a methodologically sound query is a non-trivial process. In this paper, we describe a system to help with this task, given an example set of PubMed articles to retrieve and a corresponding set of articles to exclude. The system provides the users with unigram and bigram features from the title, abstract, MeSH terms, and MeSH qualifier terms in decreasing order of precision, given a recall threshold. From this information and their knowledge of the domain, users can formulate a query and evaluate its performance. We apply the system to the task of distinguishing original research articles of functional magnetic resonance imaging (fMRI) of sensorimotor function from fMRI studies of higher cognitive functions

    Conscience and Conscientiousness

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    Paper by A. Campbell Garnet

    Controlling the layer localization of gapless states in bilayer graphene with a gate voltage

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    Experiments in gated bilayer graphene with stacking domain walls present topological gapless states protected by no-valley mixing. Here we research these states under gate voltages using atomistic models, which allow us to elucidate their origin. We find that the gate potential controls the layer localization of the two states, which switches non-trivially between layers depending on the applied gate voltage magnitude. We also show how these bilayer gapless states arise from bands of single-layer graphene by analyzing the formation of carbon bonds between layers. Based on this analysis we provide a model Hamiltonian with analytical solutions, which explains the layer localization as a function of the ratio between the applied potential and interlayer hopping. Our results open a route for the manipulation of gapless states in electronic devices, analogous to the proposed writing and reading memories in topological insulators

    Chemical Kinship: Interdisciplinary Experiments with Pollution

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    This is the final version. Available from catalystjournal.org via the DOI in this record. Feminist technoscientific research with chemicals is proliferating. This critical commentary considers how this scholarship extends environmental justice research on pollution. We are concerned with two key questions: How can we do/design ethical research with chemicals? And, what methods allow for researching chemicals without resorting to an imagined space of purity? We consider unfolding projects which reorient relations with chemicals from villainous objects with violent effects, to chemical kin. We imagine chemical kinship as a concept, an analytical tool, and a mode of relating. Emerging through feminist and anticolonial work with chemicals, it involves a tentativeness towards making normative claims about chemicals because, like kin, these materials are never entirely good nor bad, at once they can both be enabling and harmful. This commentary considers what the unfolding research with chemicals generates, and consolidates conceptualisations of chemical kinship; we ultimately articulate an agenda for ethical research with chemicals as an experimental process of invention.Economic and Social Research Counci

    Computability of simple games: A characterization and application to the core

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    The class of algorithmically computable simple games (i) includes the class of games that have finite carriers and (ii) is included in the class of games that have finite winning coalitions. This paper characterizes computable games, strengthens the earlier result that computable games violate anonymity, and gives examples showing that the above inclusions are strict. It also extends Nakamura's theorem about the nonemptyness of the core and shows that computable games have a finite Nakamura number, implying that the number of alternatives that the players can deal with rationally is restricted.Comment: 35 pages; To appear in Journal of Mathematical Economics; Appendix added, Propositions, Remarks, etc. are renumbere

    Semiconductor-metal nanoparticle molecules: hybrid excitons and non-linear Fano effect

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    Modern nanotechnology opens the possibility of combining nanocrystals of various materials with very different characteristics in one superstructure. The resultant superstructure may provide new physical properties not encountered in homogeneous systems. Here we study theoretically the optical properties of hybrid molecules composed of semiconductor and metal nanoparticles. Excitons and plasmons in such a hybrid molecule become strongly coupled and demonstrate novel properties. At low incident light intensity, the exciton peak in the absorption spectrum is broadened and shifted due to incoherent and coherent interactions between metal and semiconductor nanoparticles. At high light intensity, the absorption spectrum demonstrates a surprising, strongly asymmetric shape. This shape originates from the coherent inter-nanoparticle Coulomb interaction and can be viewed as a non-linear Fano effect which is quite different from the usual linear Fano resonance.Comment: 5 pages, 5 figures, submitted to Phys. Rev. Let
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