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1.
Acta Psychol (Amst) ; 224: 103530, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35168145

ABSTRACT

Aesthetics and evaluation of objects is becoming increasingly important in contemporary society. Although there have been many studies on processes related to computational aesthetic, a clear formalisation and visualization of the aesthetic field is still lacking. In this paper, we present a set of Machine Learning techniques and mathematical methods to extract the most important features related to aesthetical evaluation, thus making this process automatic, without the human intervention. The techniques are then applied to a sample of 83 images of triangles, produced by artists. The results of the empirical method provide a series of measurements that allow the extrapolation of mathematical aesthetic characteristics of the images and their location in the aesthetic space.


Subject(s)
Machine Learning , Esthetics , Humans
2.
J Math Biol ; 75(2): 373-417, 2017 08.
Article in English | MEDLINE | ID: mdl-28039494

ABSTRACT

In this paper we derive a reaction-diffusion-chemotaxis model for the dynamics of multiple sclerosis. We focus on the early inflammatory phase of the disease characterized by activated local microglia, with the recruitment of a systemically activated immune response, and by oligodendrocyte apoptosis. The model consists of three equations describing the evolution of macrophages, cytokine and apoptotic oligodendrocytes. The main driving mechanism is the chemotactic motion of macrophages in response to a chemical gradient provided by the cytokines. Our model generalizes the system proposed by Calvez and Khonsari (Math Comput Model 47(7-8):726-742, 2008) and Khonsari and Calvez (PLos ONE 2(1):e150, 2007) to describe Baló's sclerosis, a rare and aggressive form of multiple sclerosis. We use a combination of analytical and numerical approaches to show the formation of different demyelinating patterns. In particular, a Turing instability analysis demonstrates the existence of a threshold value for the chemotactic coefficient above which stationary structures develop. In the case of subcritical transition to the patterned state, the numerical investigations performed on a 1-dimensional domain show the existence, far from the bifurcation, of complex spatio-temporal dynamics coexisting with the Turing pattern. On a 2-dimensional domain the proposed model supports the emergence of different demyelination patterns: localized areas of apoptotic oligodendrocytes, which closely fit existing MRI findings on the active MS lesion during acute relapses; concentric rings, typical of Baló's sclerosis; small clusters of activated microglia in absence of oligodendrocytes apoptosis, observed in the pathology of preactive lesions.


Subject(s)
Demyelinating Diseases/pathology , Models, Biological , Multiple Sclerosis/pathology , Apoptosis , Humans , Magnetic Resonance Imaging
3.
IEEE Trans Neural Netw Learn Syst ; 28(5): 1228-1232, 2017 05.
Article in English | MEDLINE | ID: mdl-26863675

ABSTRACT

Cellular neural networks (CNNs) are an efficient tool for image analysis and pattern recognition. Based on elementary cells connected to neighboring units, they are easy to install in hardware, carrying out massively parallel processes. This brief presents a new model of CNN with memory devices, which enhances further CNN performance. By introducing a memristive element in basic cells, we carry out different experiments, allowing the analysis of the functions traditionally carried out by the standard CNN. Without modifying the templates considered by the scientific literature, this simple variation originates a significant improvement in  âˆ¼ 30 % of performances in pattern recognition and image processing. These progresses were experimentally calculated on the time the system requires to reach a fixed point. Moreover, the different role that each parameter has in the developed method was also analyzed to better understand the complex processing ability of these systems.

4.
Nephron ; 61(3): 356-7, 1992.
Article in English | MEDLINE | ID: mdl-1323790

ABSTRACT

The authors report on the presence of anti-HCV antibodies in a uremic chronic (UC) patient population after 6 months and 1 year with regard to certain selective preventive measures. The nonincreased number of HCV-positive subjects among the UC population could lead to the conclusion that the risk of environmental spreading of HCV is less than the risk of HBV diffusion.


Subject(s)
Hepacivirus/immunology , Hepatitis Antibodies/blood , Renal Dialysis/adverse effects , Hepatitis C/prevention & control , Hepatitis C/transmission , Humans , Time Factors , Uremia/therapy
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