33 resultados para Shaw, Robert
em CentAUR: Central Archive University of Reading - UK
Resumo:
In the second half of the 1990s, Brazil experienced a cinematic boom. Many of the new films were received enthusiastically by audiences and critics and released worldwide. This passionately argued and illuminating book provides the first comprehensive critical account of what is known as the 'Renaissance of Brazilian cinema' and demonstrates just how thought-provoking and inspiring Brazilian cinema has become. Contributors: José Carlos Avellar - Ivana Bentes - Stephanie Dennison - Verônica Ferreira Dias - Carlos Diegues - Amir Labaki - Maria Esther Maciel - José Álvaro Moisés - Laura Mulvey - Lúcia Nagib - Luiz Zanin Oricchio - Fernão Pessoa Ramos - Lisa Shaw - Robert Stam - João Luiz Vieira - Ismail Xavier.
Resumo:
Apical leaf necrosis is a physiological process related to nitrogen (N) dynamics in the leaf. Pathogens use leaf nutrients and can thus accelerate this physiological apical necrosis. This process differs from necrosis occurring around pathogen lesions (lesion-induced necrosis), which is a direct result of the interaction between pathogen hyphae and leaf cells. This paper primarily concentrates on apical necrosis, only incorporating lesion-induced necrosis by necessity. The relationship between pathogen dynamics and physiological apical leaf necrosis is modelled through leaf nitrogen dynamics. The specific case of Puccinia triticina infections on Triticum aestivum flag leaves is studied. In the model, conversion of indirectly available N in the form of, for example, leaf cell proteins (N-2(t)) into directly available N (N-1(t), i.e. the form of N that can directly be used by either pathogen or plant sinks) results in apical necrosis. The model reproduces observed trends of disease severity, apical necrosis and green leaf area (GLA) and leaf N dynamics of uninfected and infected leaves. Decreasing the initial amount of directly available N results in earlier necrosis onset and longer necrosis duration. Decreasing the initial amount of indirectly available N, has no effect on necrosis onset and shortens necrosis duration. The model could be used to develop hypotheses on how the disease-GLA relation affects yield loss, which can be tested experimentally. Upon incorporation into crop simulation models, the model might provide a tool to more accurately estimate crop yield and effects of disease management strategies in crops sensitive to fungal pathogens.