Pre and Post-hoc Diagnosis and Interpretation of Malignancy from Breast DCE-MRI

We propose a new method for breast cancer screening from DCE-MRI based on a post-hoc approach that is trained using weakly annotated data (i.e., labels are available only at the image level without any lesion delineation). Our proposed post-hoc method automatically diagnosis the whole volume and, for positive cases, it localizes the malignant lesions that led to such diagnosis. Conversely, traditional approaches follow a pre-hoc approach that initially localises suspicious areas that are subsequently classified to establish the breast malignancy -- this approach is trained using strongly annotated data (i.e., it needs a delineation and classification of all lesions in an image). Another goal of this paper is to establish the advantages and disadvantages of both approaches when applied to breast screening from DCE-MRI. Relying on experiments on a breast DCE-MRI dataset that contains scans of 117 patients, our results show that the post-hoc method is more accurate for diagnosing the whole volume per patient, achieving an AUC of 0.91, while the pre-hoc method achieves an AUC of 0.81. However, the performance for localising the malignant lesions remains challenging for the post-hoc method due to the weakly labelled dataset employed during training.Comment: Submitted to Medical Image Analysi

Effective potential in Lorentz-breaking field theory models

We calculate explicitly the one-loop effective potential in different Lorentz-breaking field theory models. First, we consider a Yukawa-like theory and, then, some examples of Lorentz-violating extensions of scalar QED. We observed, for the extended QED models, that the resulting effective potential converges to the known result in the limit in which Lorentz-symmetry is restored. Besides, the one-loop corrections to the effective potential in all the cases we studied depend on the background tensors responsible for the Lorentz symmetry violation. This have consequences in physical quantities like, for example, in the induced mass due to Coleman-Weinberg mechanism.Comment: Version accepted for publication in EPJ

Tratamento de resíduos agroindustriais com uréia.

Bagaço de cana, casca de arroz e bagana de carnauba (Copernicia prunifera) foram tratados com uréia liquida, visando-se melhorar o seu valor nutritivo para utilização na alimentação animal. Foi utilizada a uréia liquida ( a 5%) na proporção de 100 l da solução para 100 kg de resíduo. Os materiais foram incubados em silos durante 10, 20 e 30 dias. 0 delineamento foi inteiramente casualisado, com três repetições. Os três resíduos tiveram seus percentuais de proteína aumentados pela amoniação, sendo que os aumentos foram relativamente maiores nos materiais de menor teor proteico. Antes da incubação os percentuais de proteína eram de. 2,78; 4,43 e 10,03, respectivamente em bagaço de cana, casca de arroz, e bagana de carnauba, aumentando para 5,20; 7,56 e 13,97% após dez dias de incubação. Os períodos de incubação superiores a 10 dias não tiveram efeito benéfico (P>0,05), ocorrendo até mesmo decréscimo nos percentuais de proteína, com o alongamento do período de incubação

Efeitos de herbicida sobre animais em pastejo.

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Avaliacao da produtividade e do teor proteico de acessos de Stylosanthes.

Avaliacao de acessos de Stylosanthes, visando a selecao de materiais adaptados e produtivos.bitstream/item/97564/1/PAND800001.pd