178,657 research outputs found
Solutions to the nonlinear Schrödinger equation carrying momentum along a curve
No full textWe study the nonlinear Schrödinger equation - ε2 Δ ψ + V (x) ψ = | ψ |p - 1 ψ on a compact manifold or on Rn, where V is a positive potential and p > 1. As ε tends to zero, we prove existence of complex-valued solutions which concentrate along closed curves and whose phase is highly oscillatory, carrying quantum-mechanical momentum along the limit set. To cite this article: F. Mahmoudi et al., C. R. Acad. Sci. Paris, Ser. I 346 (2008). © 2007 Académie des sciences
Glycoprotein IIb/IIIa inhibitors and bivalirudin in patients undergoing percutaneous coronary intervention
No full textPercutaneous coronary intervention (PCI) is currently the standard of care for patients presenting with acute coronary syndrome (ACS), as well those patients with "stable" angina who have failed medical therapy in whom PCI is an acceptable alternative to surgical revascularization. The aim of adjunctive antiplatelet and antithrombotic therapy during PCI is to alleviate the risks associated with platelet activation and aggregation, iatrogenic plaque rupture, and thrombus formation during. The aim of this review is to summarize the evidence that has emerged from the randomized studies comparing a strategy combining heparin and a glycoprotein IIb/IIIa inhibitor (GPI) with that of bivalirudin in patients undergoing elective and urgent PCI
''Pneumonia due to Yersinia enterocolitica''
No full textJarrot, P. -A. | Mahmoudi, R. | Novella, J. -L. | Manckoundia, P.International audienc
The role of DNA damage and repair in atherosclerosis: a review
No full textThe global burden of cardiovascular disease is increasing despite therapeutic advances in medication and interventional technologies. Accumulated deoxyribonucleic acid (DNA) damage and subsequent repair pathways are now increasingly recognised as a causal factor in the initiation and progression of atherosclerosis. These molecular alterations have been shown to occur within affected vasculature, plaque microenvironment as well as in circulating cells. The DNA damage response (DDR) pathway is reliant on post-translational modification of sensing proteins which activate a signalling cascade to repair, if possible, DNA damaged sites in response to various environmental and physiological insults. This review summarises the current evidence for DNA damage in atherosclerosis, the key steps involved in the DDR pathway, DNA repair and their subsequent effects on atherosclerotic plaques, as well as the therapeutic options in managing DNA damage-induced atherosclerosis
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
"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.
Hydrodynamic instabilities in gaseous detonations: comparison of Euler, Navier–Stokes, and large-eddy simulation
No full textA large-eddy simulation is conducted to investigate the transient structure of an unstable detonation wave in two dimensions and the evolution of intrinsic hydrodynamic instabilities. The dependency of the detonation structure on the grid resolution is investigated, and the structures obtained by large-eddy simulation are compared with the predictions from solving the Euler and Navier–Stokes equations directly. The results indicate that to predict irregular detonation structures in agreement with experimental observations the vorticity generation and dissipation in small scale structures should be taken into account. Thus, large-eddy simulation with high grid resolution is required. In a low grid resolution scenario, in which numerical diffusion dominates, the structures obtained by solving the Euler or Navier–Stokes equations and large-eddy simulation are qualitatively similar. When high grid resolution is employed, the detonation structures obtained by solving the Euler or Navier–Stokes equations directly are roughly similar yet equally in disagreement with the experimental results. For high grid resolution, only the large-eddy simulation predicts detonation substructures correctly, a fact that is attributed to the increased dissipation provided by the subgrid scale model. Specific to the investigated configuration, major differences are observed in the occurrence of unreacted gas pockets in the high-resolution Euler and Navier–Stokes computations, which appear to be fully combusted when large-eddy simulation is employed
River bank protection from ship-induced waves and river flow
No full textA new equation is proposed for the design of armor units on protected river banks under the combined action of ship-induced waves and river
flow. Existing observed field and experimental data in the literature have been examined and a valuable database has been developed. Different
conditions, including the river water depth, flow velocity, river bank slope, Froude number, wave height, wave period, and wave obliquity have
been considered. Results from an empirical equation (Bhowmik, 1978) that only considers the maximum wave height and river bank slope have
been compared with the results calculated by the newly developed equation. Calculated results have also been verified against field data. Results
show that not only the maximum wave height and river bank slope but also the water depth, flow velocity, wave length, wave obliquity, and wave
period are important parameters for predicting the mean diameter of the armor units, highlighting the multivariate behavior of protecting the
river bank in the presence of ship-induced waves and river flow velocity
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
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