Towards a cross-correlation approach to strong-field dynamics in Black Hole spacetimes

The qualitative and quantitative understanding of near-horizon gravitational dynamics in the strong-field regime represents a challenge both at a fundamental level and in astrophysical applications. Recent advances in numerical relativity and in the geometric characterization of black hole horizons open new conceptual and technical avenues into the problem. We discuss here a research methodology in which spacetime dynamics is probed through the cross-correlation of geometric quantities constructed on the black hole horizon and on null infinity. These two hypersurfaces respond to evolving gravitational fields in the bulk, providing canonical "test screens" in a "scattering"-like perspective onto spacetime dynamics. More specifically, we adopt a 3+1 Initial Value Problem approach to the construction of generic spacetimes and discuss the role and properties of dynamical trapping horizons as canonical inner "screens" in this context. We apply these ideas and techniques to the study of the recoil dynamics in post-merger binary black holes, an important issue in supermassive galactic black hole mergers.Comment: 16 pages, 5 figures, contribution to the proceedings volume of the Spanish Relativity Meeting ERE2011: "Towards new paradigms", Madrid, Spain, 29 Aug-2 Sep 201

Cultivo de fruteiras em sistemas agroflorestais.

O que são Sistemas Agroflorestais (SAF). O novo conceito de sistemas agroflorestais. Interações entre componentes em sistemas agroflorestais. Critérios para escolha de espécies frutíferas para comporem sistemas agroflorestais. Diagnóstico de problemas de uso da terra e o desenho tecnologias agroflorestais

Techniques for colonial growth and protoplast production in Humicola grisea var. thermoidea

Humicola grisea is a thermophilic, cellulolytic fungus, with significant biotechnological potential for protein secretion. For convenient growth on solid medium, 70% reduction in colony diameter was achieved by the addition of 20 mM sodium citrate to modified Aspergillus complete medium (Pontecorvo et al. 1953, Adv. Genet. 5:141-238)

Criação de Chrysoperla externa para o controle biológico de pragas do algodoeiro.

bitstream/CNPA-2009-09/14457/1/CIRTEC36.pd

Pancreas Burkitt primary lymphoma in pediatric age

We present an the case of an eight-year-old Portuguese boy with no history of traveling, admitted with non-specific abdominal pain. An analytic study revealed high levels of lipase and amylase. Ultrasound, abdominal computerized tomography (CT), and an abdominal magnetic resonance imaging (MRI), were performed. The imaging findings are suggestive of a pancreatic tumor which is an extremely rare entity in children. A biopsy was performed by opened surgery and identified a Burkitt lymphoma.info:eu-repo/semantics/publishedVersio

Soil phosphorus properties and management for perennial crops in the central Amazon.

Predominant soils in the Brazilian Amazon. Phosphorus constraints to continuous soil use in the Brazilian Amazon. Phosphorus fertilization to perennial crops in the central Amazon. Phosphorus budgets in perennial crop plantations

Weighted automata as coalgebras in categories of matrices

The evolution from non-deterministic to weighted automata represents a shift from qual- itative to quantitative methods in computer science. The trend calls for a language able to reconcile quantitative reasoning with formal logic and set theory, which have for so many years supported qualitative reasoning. Such a lingua franca should be typed, poly- morphic, diagrammatic, calculational and easy to blend with conventional notation. This paper puts forward typed linear algebra as a candidate notation for such a unifying role. This notation, which emerges from regarding matrices as morphisms of suitable categories, is put at work in describing weighted automata as coalgebras in such categories. Some attention is paid to the interface between the index-free (categorial) language of matrix algebra and the corresponding index-wise, set-theoretic notation.Fundação para a Ciência e a Tecnologia (FCT

Black-hole horizons as probes of black-hole dynamics II: geometrical insights

In a companion paper [1], we have presented a cross-correlation approach to near-horizon physics in which bulk dynamics is probed through the correlation of quantities defined at inner and outer spacetime hypersurfaces acting as test screens. More specifically, dynamical horizons provide appropriate inner screens in a 3+1 setting and, in this context, we have shown that an effective-curvature vector measured at the common horizon produced in a head-on collision merger can be correlated with the flux of linear Bondi-momentum at null infinity. In this paper we provide a more sound geometric basis to this picture. First, we show that a rigidity property of dynamical horizons, namely foliation uniqueness, leads to a preferred class of null tetrads and Weyl scalars on these hypersurfaces. Second, we identify a heuristic horizon news-like function, depending only on the geometry of spatial sections of the horizon. Fluxes constructed from this function offer refined geometric quantities to be correlated with Bondi fluxes at infinity, as well as a contact with the discussion of quasi-local 4-momentum on dynamical horizons. Third, we highlight the importance of tracking the internal horizon dual to the apparent horizon in spatial 3-slices when integrating fluxes along the horizon. Finally, we discuss the link between the dissipation of the non-stationary part of the horizon's geometry with the viscous-fluid analogy for black holes, introducing a geometric prescription for a "slowness parameter" in black-hole recoil dynamics.Comment: Final version published on PR

Evaluation of manioc (Manihot esculenta Crantz) cultivation in mixed cropping systems.

Avaliação da cultura da mandioca (Manihot esculenta Crantz) em sistema e policultivo: Yields and survival rates will be presented for three manioc cultivars(Pao IM 226, Vinagre IM 157 and Mandioca IM 116), planted between the rows in two mixed cropping systems, which were treated by application of 30% or 100% of the recommended fertilizer dose and inoculation or not with mycorrhizal fungi spores. With regard to yield, there is no statistically significant difference between the treatments viewed in isolation. However, there are statistically significant differences between the cultivars Pao (10.6 tons/ha) and Vinagre (5.5 tons/ha) in system 2; between 100% fertilization (5.2 tons/ha) and 30% fertilization (3.7 tons/ha) in system 3, and between the Pao cultivars in systems 2 (10.6 tons/ha) and 3 (5.4 tons/ha). The resprouting rates of the cutting were considered to be low. There was no statistically significant difference in survival rates between the treatments. The yields are lower than those normally obtained in the region, i.e., 20.0 tons/ha for Pao, 14.0 tons/ha for Vinagre and 16,0 tons/ha for manioc in monoculture

Isolation, selection and production of vesicular-arbuscular mycorrhizal fungi (VAMF) and their application in mixed cropping systems.

bitstream/item/181010/1/ID-79940-Isolation-0-214.pd