Theory and Applications of Non-Relativistic and Relativistic Turbulent Reconnection

Realistic astrophysical environments are turbulent due to the extremely high Reynolds numbers. Therefore, the theories of reconnection intended for describing astrophysical reconnection should not ignore the effects of turbulence on magnetic reconnection. Turbulence is known to change the nature of many physical processes dramatically and in this review we claim that magnetic reconnection is not an exception. We stress that not only astrophysical turbulence is ubiquitous, but also magnetic reconnection itself induces turbulence. Thus turbulence must be accounted for in any realistic astrophysical reconnection setup. We argue that due to the similarities of MHD turbulence in relativistic and non-relativistic cases the theory of magnetic reconnection developed for the non-relativistic case can be extended to the relativistic case and we provide numerical simulations that support this conjecture. We also provide quantitative comparisons of the theoretical predictions and results of numerical experiments, including the situations when turbulent reconnection is self-driven, i.e. the turbulence in the system is generated by the reconnection process itself. We show how turbulent reconnection entails the violation of magnetic flux freezing, the conclusion that has really far reaching consequences for many realistically turbulent astrophysical environments. In addition, we consider observational testing of turbulent reconnection as well as numerous implications of the theory. The former includes the Sun and solar wind reconnection, while the latter include the process of reconnection diffusion induced by turbulent reconnection, the acceleration of energetic particles, bursts of turbulent reconnection related to black hole sources as well as gamma ray bursts. Finally, we explain why turbulent reconnection cannot be explained by turbulent resistivity or derived through the mean field approach.Comment: 66 pages, 24 figures, a chapter of the book "Magnetic Reconnection - Concepts and Applications", editors W. Gonzalez, E. N. Parke

Effect of the extract of Ricinus communis L. on the osmotic fragility, labeling of red blood cells with Technetium-99m and morphology of the cells

The aim of this study was to evaluate the influence of the proteic extract of R. communis on the cell physiology by the osmotic fragility, labeling of the blood elements with the 99mTc and cell morphology. To evaluate the osmotic fragility, the blood samples of the Wistar rats were incubated with the concentrations of R. communis and with the solutions of NaCl (0.4; 0.7; 0.9%). In the labeling of the blood elements procedure, the rat blood was treated with a solution of Tc-99m and TCA at 5%, determining the rate of radioactivity (%ATI) in the plasma (P) and in the red blood cells (RBC). The soluble and insoluble fractions of the plasma were also evaluated. The cells morphology submitted to the extract was evaluated by the optical microscopy (x40). The results indicated that the rate of the hemolysis increased in the presence of 0.125 mg/mL of the extract. There was a decay of 49.69% in the rate of ATI in the insoluble fraction of the cells, with the morphological alterations in the red blood cells. These results suggested that the extract changed the capability of binding of the red blood cells due to the stannous ion oxidation, modifying the cells structure.<br>Produtos naturais são usados freqüentemente por muitas pessoas no tratamento do câncer. O Ricinus communis L é uma Euforbiaceae que apresenta propriedades laxativas, purgativas e antitumorais. O objetivo deste trabalho é estudar a influência da fração protéica do extrato hidroalcoólico de R. communis L. na fisiologia celular através da fragilidade osmótica, da marcação de elementos sanguíneo com 99mTc e da morfologia celular. Para avaliar a fragilidade osmótica, amostras de sangue de ratos Wistar foram incubadas com concentrações de R. communis e com soluções de NaCl (0,4; 0,7; 0,9%). No procedimento de marcação de elementos sanguíneos, as amostras de sangue foram tratadas com solução de Tc-99m e TCA à 5%, determinando o percentual de radioatividade (%ATI) no plasma (P) e nas células vermelhas (RBC); as frações solúvel e insolúvel do plasma também foram avaliadas. A morfologia das células submetidas ao extrato foi avaliada por microscopia óptica (x40). Os resultados indicam que o extrato na concentração de 0,125 mg/mL provoca hemólise de 49,69% , no % ATI na fração insolúvel das células, ocorrendo alterações morfológicas das células sangüíneas. Esses resultados sugerem que o extrato radiomodifica a ligação do 99mTc às células vermelhas. Isto pode ser devido à oxidação do íon estanoso, a um processo de competição com os sítios de ligação do 99mTc ou por modificação das estruturas da membrana