Bent-Double Radio Sources as Probes of Intergalactic Gas

As the most common environment in the universe, groups of galaxies are likely to contain a significant fraction of the missing baryons in the form of intergalactic gas. The density of this gas is an important factor in whether ram pressure stripping and strangulation affect the evolution of galaxies in these systems. We present a method for measuring the density of intergalactic gas using bent-double radio sources that is independent of temperature, making it complementary to current absorption line measurements. We use this method to probe intergalactic gas in two different environments: inside a small group of galaxies as well as outside of a larger group at a 2 Mpc radius and measure total gas densities of $4 \pm 1_{-2}^{+6} \times 10^{-3}$ and $9 \pm 3_{-5}^{+10} \times 10^{-4}$ per cubic centimeter (random and systematic errors) respectively. We use X-ray data to place an upper limit of $2 \times 10^6$ K on the temperature of the intragroup gas in the small group.Comment: 6 pages, 1 figure, accepted for publication in Ap

Cultivares de mandioca de mesa da Amazônia Oriental.

bitstream/item/52971/1/PesquisaAnd040001.pd

Looking back at the EUNIS repository data using text mining techniques

Topic modelling algorithms can be applied to a large collection of documents to uncover themes and their relationship, thus adding an automatic semantic layer to the archive of documents. In this work, topic modelling has been applied to the collection of papers published at the EUNIS (European University Information Systems) annual congresses from 1997 until 2015. Drawing on the initial work of (Wilson and Bergström, 2015), this paper extends the historical analysis of the conference proceedings with the application of text mining techniques to analyse the original texts. The performed analyses include the automatic identification of the most relevant topics and their evolution throughout the years for European University Information Systems, and the quantification of the degree of internationalization and cooperation of the EUNIS annual conference.info:eu-repo/semantics/publishedVersio

Ultrarelativistic boost of spinning black rings

We study the D=5 Emparan-Reall spinning black ring under an ultrarelativistic boost along an arbitrary direction. We analytically determine the resulting shock pp-wave, in particular for boosts along axes orthogonal and parallel to the plane of rotation. The solution becomes physically more interesting and simpler if one enforces equilibrium between the forces on the ring. We also comment on the ultrarelativistic limit of recently found supersymmetric black rings with two independent angular momenta. Essential distinct features with respect to the boosted Myers-Perry black holes are pointed out.Comment: 15 pages, 2 figures. v2: added multipole expansions at spatial infinity, and a comparison with the boosted Myers-Perry solution in a new appendix. To appear in JHE

MANNA FROM HEAVEN: THE EXUBERANCE OF FOOD AS A TOPIC FOR RESEARCH IN MANAGEMENT AND ORGANIZATION

Organizations have, in the past, often been discussed as if they were Cartesian mentalities, planning agendas, learning from doing, processing information, reducing equivocality, mimicking and copying, floating disembodiedly apart from the actors who work in these organizations. We are offered representations of organizations as organically grounded metaphors that minimize the biological facticity of employees: namely, their need for food. While the inputs to organizations conceived as if they were quasi-systems are well explored, and the emotional and ‘irrational’ side of organizations is increasingly explored, the necessity of inputs to the biological systems that staff them is not. Nonetheless, despite the lack of explicit scholarly attention to food at work, its importance guarantees its hidden presence in the organizational literature, often in the context of more “serious” themes. We identify four approaches to the relationship between food, work and organization. For dessert, we propose a research menu that aims to uncover several possibilities for making the role of food in organizational life more explicit.

Plasmarings as dual black rings

We construct solutions to the relativistic Navier-Stokes equations that describe the long wavelength collective dynamics of the deconfined plasma phase of N=4 Yang Mills theory compactified down to d=3 on a Scherk-Schwarz circle and higher dimensional generalisations. Our solutions are stationary, axially symmetric spinning balls and rings of plasma. These solutions, which are dual to (yet to be constructed) rotating black holes and black rings in Scherk-Schwarz compactified AdS(5) and AdS(6), and have properties that are qualitatively similar to those of black holes and black rings in flat five dimensional supergravity.Comment: 40 pages, 40 figures. (v2) Correction to black brane equation of state, additional reference

The pros and cons of using SDL for creation of distributed services

In a competitive market for the creation of complex distributed services, time to market, development cost, maintenance and flexibility are key issues. Optimizing the development process is very much a matter of optimizing the technologies used during service creation. This paper reports on the experience gained in the Service Creation projects SCREEN and TOSCA on use of the language SDL for efficient service creation

Black hole particle emission in higher-dimensional spacetimes

In models with extra dimensions, a black hole evaporates both in the bulk and on the visible brane, where standard model fields live. The exact emissivities of each particle species are needed to determine how the black hole decay proceeds. We compute and discuss the absorption cross-sections, the relative emissivities and the total power output of all known fields in the evaporation phase. Graviton emissivity is highly enhanced as the spacetime dimensionality increases. Therefore, a black hole loses a significant fraction of its mass in the bulk. This result has important consequences for the phenomenology of black holes in models with extra dimensions and black hole detection in particle colliders.Comment: 4 pages, RevTeX 4. v3: Misprints in Tables correcte

Coleção de cultivares acidófilas de mandioca do CPATU.

bitstream/item/50150/1/DOCUMENTOS-3-CPATU.pd