New gravitational solutions via a Riemann-Hilbert approach

We consider the Riemann-Hilbert factorization approach to solving the field equations of dimensionally reduced gravity theories. First we prove that functions belonging to a certain class possess a canonical factorization due to properties of the underlying spectral curve. Then we use this result, together with appropriate matricial decompositions, to study the canonical factorization of non-meromorphic monodromy matrices that describe deformations of seed monodromy matrices associated with known solutions. This results in new solutions, with unusual features, to the field equations.Comment: 29 pages, 2 figures; v2: reference added, matches published versio

On Quantum Special Kaehler Geometry

We compute the effective black hole potential V of the most general N=2, d=4 (local) special Kaehler geometry with quantum perturbative corrections, consistent with axion-shift Peccei-Quinn symmetry and with cubic leading order behavior. We determine the charge configurations supporting axion-free attractors, and explain the differences among various configurations in relations to the presence of ``flat'' directions of V at its critical points. Furthermore, we elucidate the role of the sectional curvature at the non-supersymmetric critical points of V, and compute the Riemann tensor (and related quantities), as well as the so-called E-tensor. The latter expresses the non-symmetricity of the considered quantum perturbative special Kaehler geometry.Comment: 1+43 pages; v2: typo corrected in the curvature of Jordan symmetric sequence at page 2

Dual Brane Pairs, Chains and the Bekenstein-Hawking Entropy

A proposal towards a microscopic understanding of the Bekenstein-Hawking entropy for D=4 spacetimes with event horizon is made. Since we will not rely on supersymmetry these spacetimes need not be supersymmetric. Euclidean D-branes which wrap the event horizon's boundary will play an important role. After arguing for a discretization of the Euclidean D-brane worldvolume based on the worldvolume uncertainty relation, we count chainlike excitations on the worldvolume of specific dual Euclidean brane pairs. Without the need for supersymmetry it is shown that one can thus reproduce the D=4 Bekenstein-Hawking entropy and its logarithmic correction.Comment: 14 pages, 1 figur

Caracterização e prospecção de demanda dos produtores de banana do Norte de Minas Gerais ? Brasil.

O Norte de Minas é o terceiro maior polo produtor de banana do país, com produção de 322,4 mil toneladas em 14,1 mil hectares, com valor da produção de R$ 369,0 milhões, posicionando-se logo após o Vale do Ribeira em São Paulo e o Norte Catarinense em Santa Catarina, respectivamente, primeiro e segundo maiores polos produtores de banana do Brasil (1). Em Minas Gerais a região destaca-se como a maior produtora, sendo responsável por 49,3% da banana produzida no Estado. É a principal fruteira cultivada no Norte de Minas, o que corresponde a 59,5% da produção de frutas da região

Implantação e evolução dos trabalhos de pesquisa participativa em melhoramento de mandioca no Nordeste Brasileiro.

Este trabalho faz um breve histórico sobre a implantação e os avanços da pesquisa participativa em melhoramento de mandioca (PPMM) no Nordeste do Brasil, desenvolvida pela Embrapa Mandioca e Fruticultura. A metodologia de pesquisa participativa em melhoramento de mandioca foi desenvolvida inicialmente no Centro Internacional de Agricultura Tropical (CIAT), na Colômbia e introduzida e adaptada as condições das regiões semi-árida do Nordeste brasileiro a partir de 1993. Os primeiros resultados demostraram que a metodologia de PPMM como um complemento ao método convencional de melhoramento genético da cultura.bitstream/item/81562/1/Implantacao-evolucao-Wania-Fukuda-Docuemntos-92-2000.pdfMemória

Ante‐natal and post‐natal influences on neonatal immunity, growth and puberty of calves—a review

Calf immunity, growth and puberty are important factors affecting heifer productivity. The first four weeks of age are critical for reducing calf morbidity and mortality. It is well documented that colostrum is paramount to neonatal nutrition and passive immunity, however, adap-tation to extra‐uterine life starts early during embryonic development. Therefore, successful calf rearing strategies are underpinned by adequate maternal nutrition during gestation, and good co-lostrum management. A deeper understanding of these interactions paves the way for developing strategies to improve immune responses to environmental pathogens, optimal growth and timely attainment of puberty in calves. The literature reviewed here shows that there are opportunities to enhance the future performance of cattle paying attention to the interaction of nutrition and immunity at each developmental stage. Therefore, the objective of this review is to give the reader an overview of interactions between immunity, growth and puberty in dairy calves and highlight how these influence future performances