Modern electronic instrumentation techniques are being introduced in the programs of the Physics and Physical Engineering courses and, in this context, the programmable logic devices play an important role. We present the fundamental steps for the design, development, and validation of systems based on programmable logic devices. Two digital filters have been implemented for illustrating the guide procedures. The results show that the function-response complies with the common requirements of generic filter performance. This work is targeted at students and lectures and aims stimulate and challenge them to develop electronic instrumentation using programmable logic devices in teaching activities.

Este projeto se propõe a desenvolver um setup prático para implementação de circuitos com a finalidade de demonstrar conceitos de processamento digital de sinais em sala de aula. A ideia é criar circuitos digitais de processamento digital de sinais a partir do uso da programação VHDL e utilizando as plataformas computacionais QuartusII/Modelsim/Octave, para serem utilizados na forma de um kit didático para realização de experimentos. O setup é composto pelos conversores Analógico/Digital e Digital/Analógico, um filtro Butterworth de reconstrução passabaixa de segunda ordem e a Evaluation Board DE1 (Altera e Terasic, 2010).

Background: Malignant gliomas are the most prevalent primary cerebral tumor. Preoperative imaging plays an important role, and the prognosis is closely related to surgical resection and histomolecular aspects. Our goal was to correlate Ki67 indexes with tumoral volumetry in semiautomatic segmentation on preoperative magnetic resonance images in a 5-ALA assisted resection cohort.Methods: We included initially seventy-eight IDH-wildtype glioblastoma patients with complete preoperative imaging submitted to 5-ALA assisted resections. Clinical, surgical, and histomolecular ndings were also obtained. Preoperative magnetic resonance studies were preprocessed and segmented semiautomatically on VISVA for whole tumor (WT) on 3D FLAIR, enhancing tumor (ET), and necrotic core (NC) on 3D post-gadolinium T1. Edema volumes (ED) were obtained from the subtraction of ET and NC from WT. According to previous studies, we used a 20% cutoff for Ki67 for statistical analysis.Results: Final sample was of 48 patients. Higher Ki-67 indexes correlated positively with higher WT (p = 0,01), ET (p = 0,03) and ED volumes (p = 0,04), with no correlation with NC volumes (p = 0,18). Ki67indexes were also higher in 5-ALA compromised margins (p = 0,01).Conclusions: There is a correlation between Ki67, the metabolically active tumoral volumes, and 5-ALA compromised margins. Tumoral volumetry aspects (WT, ET, and ED), except for NC, correlated directly with Ki67 indexes. Methodological inconsistencies are probably responsible for contradictory literature ndings, and further studies are needed to validate and reproduce these ndings.