50,735 research outputs found

    Ten Simple Rules for Searching and Organizing the Scientific Literature

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    The exponentially increasing number of published papers (1.4 million per year by one estimate) makes it more and more difficult for us to manage the flood of scientific information. Each of us has acquired some protocol to find and organize journal articles and other references over the course of our careers. Most of those protocols are likely to have been formed by old routines or idleness rather than a structured approach to save time and frustration over the long run. Furthermore, with the Web 2.0 revolution, new ways of handling information are emerging (O’Reilly 2005). For example, traditional standalone tools for reference management like EndNote are being supplemented by centralized resources like RefWorks and social bookmarking sites as described subsequently. This fusion of personal and public information offers the promise of efficiency through better organization, which in turn leads to better science.

How can seasoned scientists do better using these tools and those newer to the field start off in the right way? To start to answer that question, I present ten simple rules to master the search and organization of new literature. This is not meant to be comprehensive. It represents the experiences of a few and I welcome your thoughts, through comments to this article, on what you do to keep your references organized.

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    The Electroweak Standard Model in the Axial Gauge

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    We derive the Feynman rules of the standard model in the axial gauge. After this we prove that the fields ϕW\phi_W and ϕZ\phi_Z do not correspond to physical particles. As a consequence, these fields cannot appear as incoming or outgoing lines in Feynman graphs. We then calculate the contribution of these fields in the case of a particular decay mode of the top quark.Comment: 16 pages, no figures. Added derivation of polarization su

    Field dependent quasiparticles in the infinite dimensional Hubbard model

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    We present dynamical mean field theory (DMFT) results for the local spectral densities of the one- and two-particle response functions for the infinite dimensional Hubbard model in a magnetic field. We look at the different regimes corresponding to half-filling, near half-filling and well away from half-filling, for intermediate and strong values of the local interaction UU. The low energy results are analyzed in terms of quasiparticles with field dependent parameters. The renormalized parameters are determined by two different methods, both based on numerical renormalization group (NRG) calculations, and we find good agreement. Away from half-filling the quasiparticle weights, zσ(H)z_\sigma(H), differ according to the spin type σ=\sigma=\uparrow or σ=\sigma=\downarrow. Using the renormalized parameters, we show that DMFT-NRG results for the local longitudinal and transverse dynamic spin susceptibilities in an arbitrary field can be understood in terms of repeated scattering of these quasiparticles. We also check Luttinger's theorem for the Hubbard model and find it to be satisfied in all parameter regimes and for all values of the magnetic field.Comment: 14 pages, 21 figure

    On some derivatives of phenylethers, 2

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    Products and the synthesis of chloronitrobenzol with certain phenolates are discussed, as is the p-oxyphenylether occasionally produced. Yield, melting point, and physical description are given for each product. The products include 2,4'-dinitrophenylether; 2,2'-dinitrophenylether; p-nitrophenylether-p-oxybenzoic acid and its methylester; p-aminophenylether-p-oxybenzoic acid, its sulfate, and its barium salt; and p-oxypenylether

    Quantitative study of laterally inhomogeneous wetting films

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    Based on a microscopic density functional theory we calculate the internal structure of the three-phase contact line between liquid, vapor, and a confining wall as well as the morphology of liquid wetting films on a substrate exhibiting a chemical step. We present a refined numerical analysis of the nonlocal density functional which describes the interface morphologies and the corresponding line tensions. These results are compared with those predicted by a more simple phenomenological interface displacement model. Except for the case that the interface exhibits large curvatures, we find that the interface displacement model provides a quantitatively reliable description of the interfacial structures.Comment: 31 pages, RevTeX, 13 figure

    NaCl transport stimulates prostaglandin release in cultured renal epithelial (MDCK) cells

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    Prostaglandins (PGs) can modulate a variety of renal functions, including Na+ and Cl- reabsorption. However, it is not known if a direct interdependence exists between PG synthesis and transport activity. The present study was done to find out whether or not the rate of NaCl transport has an influence on PG synthesis in renal tubular cells. For our studies we used cultures of so-called high-resistance MDCK cells, which were originally derived from canine kidney. This cell type has a loop diuretic- and ouabain-sensitive NaCl transport that can be enhanced by activation of the adenylate cyclase (AC). In MDCK cell cultures we found that each state of increased NaCl transport during stimulation of AC by either epinephrine (10(-6) M), isoprenaline (10(-5) M), or forskolin (10(-5) M) was accompanied by a twofold increase in PG release. During inhibition of NaCl transport by furosemide (10(-4) M) or ouabain (2 X 10(-4) M), stimulation of AC failed to increase PGE2 release, whereas basal PG production was not inhibited by either furosemide or ouabain. Furthermore, PG formation during activation of AC was dependent on the concentration of extracellular Na+, whereas PG formation in the absence of activators of AC was independent of extracellular Na+. These results suggest that increased NaCl transport stimulates PG formation in cultures of high-resistance MDCK cells

    A proof of factorization for B -> D pi

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    We prove that the matrix elements of four fermion operators mediating the decay B^0 -> D^+ \pi^- and B^- -> D^0 \pi^- factor into the product of a form factor describing the B -> D transition and a convolution of a short distance coefficient with the nonperturbative pion light-cone wave function. This is shown to all orders in alpha_s, up to corrections suppressed by factors of 1/mb, 1/mc, and 1/E_pi. It is not necessary to assume that the pion state is dominated by the q-qbar Fock state.Comment: 4 pages, 3 figs, PRL versio
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