Pilar Calvo

Pilar Calvo


Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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8 May 2018 in Neural Computing and Applications
Verified
Journal Article
Open access
PDF file
KLKarmele Lopez-De-Ipina
Karmele Lopez-De-Ipina
UMU. Martinez-De-Lizarduy
U. Martinez-De-Lizarduy
PCPilar Calvo
Pilar Calvo
BBB. Beitia
B. Beitia
JGJ. García-Melero
J. García-Melero
PSP. Sanz
P. Sanz
Alzheimer’s disease is characterized by a progressive and irreversible cognitive deterioration. In a previous stage, the so-called Mild Cognitive Impairment or cognitive loss appears. Nevertheless, this previous stage does not seem sufficiently severe to interfere in independent abilities of daily life, so it is usually diagnosed inappropriately. Thus, its detection is a crucial challenge to be addressed by medical specialists. This paper presents a novel proposal for such early diagnosis based on automatic analysis of speech and disfluencies, and Deep Learning methodologies. The proposed tools could be useful for supporting Mild Cognitive Impairment diagnosis. The Deep Learning approach includes Convolutional Neural Networks and nonlinear multifeature modeling. Additionally, an automatic hybrid methodology is used in order to select the most relevant features by means of nonparametric Mann–Whitney U test and Support Vector Machine Attribute evaluation.

16 July 2018 in Entropy
Verified
Journal Article
Open access
PDF file
KLKarmele Lopez-De-Ipina
Karmele Lopez-De-Ipina
Jordi Solé-CasalsJordi Solé-Casals
Jordi Solé-Casals
Marcos Faundez-ZanuyMarcos Faundez-Zanuy
Marcos Faundez-Zanuy
PCPilar Calvo
Pilar Calvo
ESEnric Sesa
Enric Sesa
ABAlberto Bergareche
Alberto Bergareche
Among neural disorders related to movement, essential tremor has the highest prevalence; in fact, it is twenty times more common than Parkinson’s disease. The drawing of the Archimedes’ spiral is the gold standard test to distinguish between both pathologies. The aim of this paper is to select non-linear biomarkers based on the analysis of digital drawings. It belongs to a larger cross study for early diagnosis of essential tremor that also includes genetic information. The proposed automatic analysis system consists in a hybrid solution: Machine Learning paradigms and automatic selection of features based on statistical tests using medical criteria. Moreover, the selected biomarkers comprise not only commonly used linear features (static and dynamic), but also other non-linear ones: Shannon entropy and Fractal Dimension. The results are hopeful, and the developed tool can easily be adapted to users; and taking into account social and economic points of view, it could be very helpful in real complex environments.

16 May 2016 in Entropy
Verified
Journal Article
Open access
PDF file
KLKarmele Lopez-De-Ipina
Karmele Lopez-De-Ipina
Jordi Solé-CasalsJordi Solé-Casals
Jordi Solé-Casals
Marcos Faundez-ZanuyMarcos Faundez-Zanuy
Marcos Faundez-Zanuy
PCPilar Calvo
Pilar Calvo
ESEnric Sesa
Enric Sesa
ABAlberto Bergareche
Alberto Bergareche
Biomedical systems produce biosignals that arise from interaction mechanisms. In a general form, those mechanisms occur across multiple scales, both spatial and temporal, and contain linear and non-linear information. In this framework, entropy measures are good candidates in order provide useful evidence about disorder in the system, lack of information in time-series and/or irregularity of the signals. The most common movement disorder is essential tremor (ET), which occurs 20 times more than Parkinson’s disease. Interestingly, about 50%–70% of the cases of ET have a genetic origin. One of the most used standard tests for clinical diagnosis of ET is Archimedes’ spiral drawing. This work focuses on the selection of non-linear biomarkers from such drawings and handwriting, and it is part of a wider cross study on the diagnosis of essential tremor, where our piece of research presents the selection of entropy features for early ET diagnosis. Classic entropy features are compared with features based on permutation entropy. Automatic analysis system settled on several Machine Learning paradigms is performed, while automatic features selection is implemented by means of ANOVA (analysis of variance) test. The obtained results for early detection are promising and appear applicable to real environments.

30 June 2017 in Loquens
Verified
Journal Article
Open access
ULUnai Martinez de Lizarduy
Unai Martinez de Lizarduy
PCPilar Calvo
Pilar Calvo
PGPedro Gómez-Vilda
Pedro Gómez-Vilda
MEMirian Ecay-Torres
Mirian Ecay-Torres
KLKarmele Lopez-De-Ipina
Karmele Lopez-De-Ipina
Internet of things and smart cities are becoming a reality. Nowadays, more and more devices are interconnected and in order to deal with this new situation, data processing speeds are increasing to keep the pace. Smart devices like tablets and smartphones are accessible to a wide part of society in developed countries, and Internet connections for data exchange make it possible to handle large volumes of information in less time. This new reality has opened up the possibility of developing client-server architectures focused on clinical diagnosis in real time and at a very low cost. This paper illustrates the design and implementation of the ALZUMERIC system that is oriented to the diagnosis of Alzheimer’s disease (AD). It is a platform where the medical specialist can gather voice samples through non-invasive methods from patients with and without mild cognitive impairment (MCI), and the system automatically parameterizes the input signal to make a diagnose proposal. Although this type of impairment produces a cognitive loss, it is not severe enough to interfere with daily life. The present approach is based on the description of speech pathologies with regard to the following profiles: phonation, articulation, speech quality, analysis of the emotional response, language perception, and complex dynamics of the system. Privacy, confidentiality and information security have also been taken into consideration, as well as possible threats that the system could suffer, so this first prototype of services offered by ALZUMERIC has been targeted to a predetermined number of medical specialists.

AOAratz Olaizola
Aratz Olaizola
Ibai ErrekagorriIbai Errekagorri
Ibai Errekagorri
KLKarmele Lopez-De-Ipina
Karmele Lopez-De-Ipina
PCPilar Calvo
Pilar Calvo
JCJulen Castellano
Julen Castellano
The objective of this study was to compare the external load of training sessions using as a reference an official competition match in women’s football in order to find if the training sessions replicate the competition demands. Twenty-two semi-professional football players were analyzed during 17 weeks in the first phase of the competitive period of the 2020–2021 season of Spanish women’s football. In addition to the competition (Official Matches, OM), four types of sessions were distinguished: strength or intensity (INT), endurance or extensity (EXT), velocity (VEL), and activation or pre-competitive (PREOM). The external load variables recorded were total distance (TD), high-speed running (HSR), sprint (Sprint), accelerations (ACC2), decelerations (DEC2), player load (PL), distance covered per minute (TDmin), high metabolic load distance (HMLD), and total impacts. The main results were that the external load demanded was different according to the type of session, being, in all cases, much lower than OM. The variables referring to the neuromuscular demands (ACC2 and DEC2) were higher in the INT sessions, the TD variable in the EXT sessions and the velocity variables (HSR and Sprint) in the VEL sessions. We can conclude that there was an alternating horizontal distribution of training loads within the competitive micro-cycle in women’s football, although the order was not the usual one for tactical periodization.