Massless and massive graviton spectra in anisotropic dilatonic braneworld cosmologies

We consider a braneworld model in which an anisotropic brane is embedded in a dilatonic background. We solve the background solutions and study the behavior of the perturbations when the universe evolves from an inflationary Kasner phase to a Minkowski phase. We calculate the massless mode spectrum, and find that it does not differ from what expected in standard four-dimensional cosmological models. We then evaluate the spectrum of both light (ultrarelativistic) and heavy (nonrelativistic) massive modes, and find that, at high energies, there can be a strong enhancement of the Kaluza-Klein spectral amplitude, which can become dominant in the total spectrum. The presence of the dilaton, on the contrary, decrease the relative importance of the massive modes.Comment: 18 pages, 4 figures, Typos correction

An Approach and an Eclipse Based Environment for Enhancing the Navigation Structure of Web Sites

This paper presents an approach based on information retrieval and clustering techniques for automatically enhancing the navigation structure of a Web site for improving navigability. The approach increments the set of navigation links provided in each page of the site with a semantic navigation map, i.e., a set of links enabling navigating from a given page to other pages of the site showing similar or related content. The approach uses Latent Semantic Indexing to compute a dissimilarity measure between the pages of the site and a graph-theoretic clustering algorithm to group pages showing similar or related content according to the calculated dissimilarity measure. AJAX code is finally used to extend each Web page with an associated semantic navigation map. The paper also presents a prototype of a tool developed to support the approach and the results from a case study conducted to assess the validity and feasibility of the proposal

Miliary Tuberculosis and the postpartum state

Journal ArticleIn 1985, a resurgence of tuberculosis began in the United States. In conjunction with this resurgence, there has been an increase in the number of atypical presentations of the disease. We recently treated a patient who had disseminated tuberculosis that became manifest in the postpartum state. Whereas postpartum progression of tuberculosis was a well-recognized clinical entity in the preantibiotic era, few reports have dealt with the issue recently. We present this case as a timely reminder of the many faces of tuberculosis

How Companies Restrain Means–Ends Decoupling: A Comparative Case Study of CSR Implementation

We use the concept of means–ends decoupling to examine why companies continue to be major contributors to environmental and social problems despite committing increasingly to corporate social responsibility (CSR). Specifically, we ask: How do companies restrain (versus fail to restrain) means–ends decoupling? We answer this question through a comparative case study of four multinational companies with different levels of means–ends decoupling. Based on interviews and secondary data, we inductively identify two distinct approaches to CSR implementation: experimental vs. consistency-oriented CSR implementation. Experimental CSR implementation means that companies (1) produce CSR knowledge about what is happening in specific CSR contexts and use this knowledge to (2) adapt CSR practices to local circumstances – an interplay that restrains means–ends decoupling. Consistency-oriented CSR implementation lacks this interplay between knowledge production and practice adaptation, which fosters means–ends decoupling. Our model of experimental versus consistency-oriented CSR implementation advances two streams of research. First, we advance research on means–ends decoupling by highlighting the importance of experimentation for restraining means–ends decoupling. Second, we advance research on the impact of CSR activities by questioning the widespread assumption that consistency should be at the heart of CSR implementation

Gaussian Approximation Potentials: the accuracy of quantum mechanics, without the electrons

We introduce a class of interatomic potential models that can be automatically generated from data consisting of the energies and forces experienced by atoms, derived from quantum mechanical calculations. The resulting model does not have a fixed functional form and hence is capable of modeling complex potential energy landscapes. It is systematically improvable with more data. We apply the method to bulk carbon, silicon and germanium and test it by calculating properties of the crystals at high temperatures. Using the interatomic potential to generate the long molecular dynamics trajectories required for such calculations saves orders of magnitude in computational cost.Comment: v3-4: added new material and reference

Generating Flower Images and Shapes with Compositional Pattern Producing Networks

Various embodiments are disclosed for generating an image from a Compositional Pattern Producing Network (CPPN). One such method includes receiving, in the CPPN, a series of polar coordinates {r, 0}; outputting, by the CPPN, a series of pixel values, each of the pixel values corresponding to one of the polar coordinates; and displaying the pixel values at the corresponding polar coordinates to product the image

Assessment of a desiccant cooling system in a traditional and innovative nanofluid HVAC system

The topic of energy saving is a constant in everyday life, and it is widespread all over the world. Space heating using solar panels is the most used renewable source of energy, but the application of solar energy for cooling the fluids used for refrigeration is growing very fast. Among the techniques used for refrigeration, this work focused on Desiccant Cooling. In particular, with the use of dynamic simulation software, it was possible to study the heat supplied and the energy consumption of a Heating Ventilation Air Conditioning (HVAC) system of a university building and to compare consumption with those of a Desiccant Cooling system applied to the same building. Four different cases were simulated: two related to the HVAC system, one of which operates with water and glycol and the other one with nanofluid, and the other ones to the Desiccant Cooling system with both types of fluids mentioned above. Keeping the same energy demand of the building in all the simulations, it was found that in summer the Desiccant Cooling system had higher performance than the traditional HVAC system and that the use of the nanofluid in both types of conditioning systems further increased the performance of 21%. Simulations were carried out using TRNSYS software

Bethe Ansatz Equations for General Orbifolds of N=4 SYM

We consider the Bethe Ansatz Equations for orbifolds of N =4 SYM w.r.t. an arbitrary discrete group. Techniques used for the Abelian orbifolds can be extended to the generic non-Abelian case with minor modifications. We show how to make a transition between the different notations in the quiver gauge theory.Comment: LaTeX, 66 pages, 9 eps figures, minor corrections, references adde