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The issue of testability, intended as a measure of solvability of the parametric fault diagnosis problem in analog linear time-invariant electrical networks, is addressed in this paper. Independently of the considered fault location method, such important metric provides information as to how many and which components can be diagnosed. For the reader's convenience and to set up an appropriate framework for our main achievements, our first concern is to rederive fundamental results concerning analog linear time-invariant electrical network testability hinging on multifrequency measurements. Then a novel algorithm for testability analysis is proposed, which is straightforward and able to circumvent the main drawbacks of formerly proposed methods, such as computational and conceptual complexities, proneness to roundoff errors, and vulnerability to particular cases. A computer program that implements such algorithm is also described. Moreover, the possibility of employing further simplified versions of the latter and their links with a previously proposed approach are discussed on rigorous bases. Finally, examples are provided, which show the effectiveness and robustness of the new algorithms, also by means of a comparison with the old ones. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT The paper presents the main capabilities and the possible applications in the teaching area of Electrical/Electronic Engineering of a software system developed by the authors and aimed at simulating analog linear (or linearized) circuits. The work is the enrichment, enhancement and extension of some programs developed by the same authors along the last two decades and distributed in many schools, institutions, industries, and research centers for different purposes. The feedback (in terms of suggestions, corrections, and improvement requests) has been collected to generate a completely renewed software that could definitely become a really efficient tool in the field of analog circuits, also filling the gap which still exists in the use of very famous and classical circuit simulators (as, for instance, the SPICE family). The application of the past experience involves several courses, as it will be described in the final sections of paper. © 2015 Wiley Periodicals, Inc. Comput. Appl. Eng. Educ. 24:44-57, 2016; View this article online at ; DOI [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to assess vascular endothelial growth factor (VEGF) expression and microvessel density (MVD) in maxillary sinus augmentation with autogenous bone and different graft materials for evaluating their angiogenic potential. Methods: Biopsies were harvested 10 months after sinus augmentation with a combination of autogenous bone and different graft materials: hydroxyapatite (HA, n = 6 patients), demineralized freeze-dried bone allograft (DFDBA, n = 5 patients), calcium phosphate (CP, n = 5 patients), Ricinus communis polymer ( n = 5 patients) and control group – autogenous bone only ( n = 13 patients). Results: In all the samples, higher intensities of VEGF expression were prevalent in the newly formed bone, while lower intensities of VEGF expression were predominant in the areas of mature bone. The highest intensity of VEGF expression in the newly formed bone was expressed by HA ( P < 0.001) and CP in relation to control ( P < 0.01) groups. The lowest intensities of VEGF expression in newly formed bone were shown by DFDBA and polymer groups ( P < 0.05). When comparing the different grafting materials, higher MVD were found in the newly formed bone around control, HA and CP ( P < 0.001). Conclusion: Various graft materials could be successfully used for sinus floor augmentation; however, the interactions between bone formation and angiogenesis remain to be fully characterized. [ABSTRACT FROM AUTHOR]

Aim To identify type I- (I-CF) and type III-collagen fibrils (III-CF) and chondroitin 4/6 sulphate (CS) within human pre-dentine by means of a correlative analysis under field emission in-lens-scanning electron microscopy (FEI-SEM) and transmission electron microscopy (TEM). Methodology Human-extracted teeth were obtained and submitted to either a pre-embedding or a post-embedding immunolabelling procedure using monoclonal primary antibodies anti-I-CF, anti-III-CF and anti-CS. Gold-conjugated secondary antibodies were coupled to primary antibodies to visualize labelling under the electron beam. Correlative labelling patterns were obtained for I-CF and CS under both FEI-SEM and TEM. Results Field emission in lens-SEM analysis revealed an intricate three-dimensional network of I-CF and CS clarifying the intimate relationship between the two main components of the pre-dentine organic matrix. TEM analysis revealed odontoblasts exhibiting intracellular labelling for CS, which became more intense and diffuse over the pre-dentine organic matrix. The same diffuse immunoreaction was revealed for I-CF, whereas a weak immunolocalization of III-CF was found scattered throughout the pre-dentine layer and over the collagen fibrils. Conclusions Both the pre- and post-embedding immunohistochemical approaches have led to the visualization of CF- and CS-labelling distribution within the pre-dentine layer, adding further knowledge on the elucidation of collagen–proteoglycans interaction in the organic matrix of human dental roots. [ABSTRACT FROM AUTHOR]

Fractal dimension (FD) in tissue specimens from patients with oral squamous cell carcinoma (OSCC) was evaluated. FD values in different stages of OSCC, and the correlations with clinicopathological variables and patient survival were investigated. Histological sections from OSCC and control non-neoplastic mucosa specimens were stained with hematoxylin-eosin for pathological analysis and with Feulgen for nuclear evaluation. FD in OSCC groups vs. controls revealed statistically significant differences (P < 0.001). In addition, a progressive increase of FD from stage I and II lesions and stage III and IV lesions was observed, with statistically significant differences (P = 0.003). Moreover, different degrees of tumor differentiation showed a significant difference in the average nuclear FD values (P = 0.001). A relationship between FD and patients' survival was also detected with lower FD values associated to longer survival time and higher FD values with shorter survival time (P = 0.034). These data showed that FD significantly increased during OSCC progression. Thus, FD could represent a novel prognostic tool for OSCC, as FD values significantly correlated with patient survival. Fractal geometry could give insights into tumor morphology and could become an useful tool for analyzing irregular tumor growth patterns., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)