131,046 research outputs found
Solar neutrino experiments and determination of the neutrino oscillation parameters
No full textThis paper investigates present evidence and future tests for neutrino oscillations from solar neutrino experiments. First we analyze solar neutrino data (chlorine, Kamiokande, and gallium) in the MSW framework, including all effects that are known to influence neutrino evolution from production to detection sites, and compare our analysis with others. Next we quantitatively discuss the potential of future solar neutrino experiments (SuperKamiokande, SNO, and Borexino) for testing the MSW hypothesis, with special attention to those tests that are independent of the solar model (energy spectra, charged to neutral current ratio)
Gouts – 25 route d’Audon
No full textL’intervention s’est faite durant les excavations des fondations d’un nouveau garage au lieu-dit Bigné. Le garage précédant, composé d’une chape sans fondations, a été détruit au préalable. Cette propriété est sous surveillance archéologique puisque c’est sur ces terrains que des prospections ont eu lieu entre 1999 et 2002 (D. Vignaud, centre de recherches archéologiques sur les Landes) et qu’une fouille programmée dirigée par une équipe d’étudiants de l’université de Pau et des Pays de l’Ado..
MeSH term explosion and author rank improve expert recommendations
No full textInformation overload is an often-cited phenomenon that reduces the productivity, efficiency and efficacy of scientists. One challenge for scientists is to find appropriate collaborators in their research. The literature describes various solutions to the problem of expertise location, but most current approaches do not appear to be very suitable for expert recommendations in biomedical research. In this study, we present the development and initial evaluation of a vector space model-based algorithm to calculate researcher similarity using four inputs: 1) MeSH terms of publications; 2) MeSH terms and author rank; 3) exploded MeSH terms; and 4) exploded MeSH terms and author rank. We developed and evaluated the algorithm using a data set of 17,525 authors and their 22,542 papers. On average, our algorithms correctly predicted 2.5 of the top 5/10 coauthors of individual scientists. Exploded MeSH and author rank outperformed all other algorithms in accuracy, followed closely by MeSH and author rank. Our results show that the accuracy of MeSH term-based matching can be enhanced with other metadata such as author rank
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Une culture à contre-courant. Histoire
No full textPerry Anderson, A Culture in Contraflow (Recent British Historiography)
Variegated forms of self-proclaimed historiographic revision - not a few Meriting the label of reaction - have taken the initiative in recent years (Geoffrey Elton, J. C. D. Clark). Compared with the United States, there can be no doubt of the conservative impetus of the past decade, represented by such ideologies as Thatcherite individualism or Jacobite obscurantism But the best historians of the Left have continued to produce major work challenging or undercutting the themes of the new conservatism.Anderson Perry, Vignaud Florence. Une culture à contre-courant. Histoire. In: L'Homme et la société, N. 110, 1993. Sciences sociales et socialisme en grande-bretagne. pp. 61-72
Coexistence of ordered and disordered phases in potts models in the continuum
No full textThis is the second of two papers on a continuum version of the Potts model, where particles are points in a(d) , da parts per thousand yen2, with a spin which may take Sa parts per thousand yen3 possible values. Particles with different spins repel each other via a Kac pair potential of range gamma (-1), gamma > 0. In this paper we prove phase transition, namely we prove that if the scaling parameter of the Kac potential is suitably small, given any temperature there is a value of the chemical potential such that at the given temperature and chemical potential there exist S+1 mutually distinct DLR measures
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
Potts models in the continuum. Uniqueness and exponential decay in the restricted ensembles
No full textIn this paper we study a continuum version of the Potts model, where particles are points in R-d supercript stop, d >= 2, with a spin which may take S >= 3 possible values. Particles with different spins repel each other via a Kac pair potential of range gamma(-1), gamma > 0. In mean field, for any inverse temperature beta there is a value of the chemical potential lambda (beta) at which S+1 distinct phases coexist. We introduce a restricted ensemble for each mean field pure phase which is defined so that the empirical particles densities are close to the mean field values. Then, in the spirit of the Dobrushin-Shlosman theory (Dobrushin and Shlosman in J. Stat. Phys. 46(5-6):983-1014, 1987), we prove that while the Dobrushin high-temperatures uniqueness condition does not hold, yet a finite size condition is verified for gamma small enough which implies uniqueness and exponential decay of correlations. In a second paper (De Masi et al. in Coexistence of ordered and disordered phases in Potts models in the continuum, 2008), we will use such a result to implement the Pirogov-Sinai scheme proving coexistence of S+1 extremal DLR measures
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