Xavier Marimon - Academia.edu (original) (raw)
Papers by Xavier Marimon
Applied sciences, Mar 19, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Healthcare
Background: In handball, the kinematics of the frontal plane seem to be one of the most important... more Background: In handball, the kinematics of the frontal plane seem to be one of the most important factors for the development of lower limb injuries. The knee valgus angle is a fundamental axis for injury prevention and is usually measured with 2D systems such as Kinovea software (Version 0.9.4.). Technological advances such as computer vision have the potential to revolutionize sports medicine. However, the validity and reliability of computer vision must be evaluated before using it in clinical practice. The aim of this study was to analyze the test-retest and inter-rater reliability and the concurrent validity of a beta version app based on computer vision for the measurement of knee valgus angle in elite handball athletes. Methods: The knee valgus angle of 42 elite handball athletes was measured. A frontal photo during a single-leg squat was taken, and two examiners measured the angle by the beta application based on computer vision at baseline and at one-week follow-up to calcu...
Journal of Clinical Medicine
Introduction: Neck pain is one of the most frequent reasons for consultation in primary care. Cli... more Introduction: Neck pain is one of the most frequent reasons for consultation in primary care. Clinicians evaluate different variables, including movement and cervical strength, to determine the prognosis of patients. Usually, the tools employed for this purpose are expensive and bulky, or more than one is needed. This study aims to describe a novel device designed to assess the cervical spine and describe its test–retest reliability. Methods: The Spinetrack device was designed to measure the strength of deep cervical flexor muscles and the chin-in and chin-out movement of the upper cervical spine. A test–retest reliability study was developed. The flexion, extension and strength needed to move the Spinetrack device were registered. Two measurements were developed, with one week between each assessment. Results: Twenty healthy subjects were evaluated. The strength of the deep cervical flexor muscles in the first measurement was 21.18 ± 3.15 Newtons, the displacement movement during c...
Mathematics
This study reports a method for the detection of mechanical signaling anomalies in cardiac tissue... more This study reports a method for the detection of mechanical signaling anomalies in cardiac tissue through the use of deep learning and the design of two anomaly detectors. In contrast to anomaly classifiers, anomaly detectors allow accurate identification of the time position of the anomaly. The first detector used a recurrent neural network (RNN) of long short-term memory (LSTM) type, while the second used an autoencoder. Mechanical contraction data present several challanges, including high presence of noise due to the biological variability in the contraction response, noise introduced by the data acquisition chain and a wide variety of anomalies. Therefore, we present a robust deep-learning-based anomaly detection framework that addresses these main issues, which are difficult to address with standard unsupervised learning techniques. For the time series recording, an experimental model was designed in which signals of cardiac mechanical contraction (right and left atria) of a C...
International Journal of Molecular Sciences
This study aimed to find the optimum mechanical characteristics of the restorative materials for ... more This study aimed to find the optimum mechanical characteristics of the restorative materials for the manufacture of implant crowns subjected to impact loading when different combinations of materials are used for the inner and outer crown. Several combinations of external–internal crown restorative materials were analyzed. The dynamic stresses at eight different zones of a dental implant subjected to an impact load and the influence of several mechanical properties, such as the Young’s modulus, Poisson’s ratio, density, and initial velocity, were analyzed and compared. A detailed 3D model was created, including the crown, the retention screw, the implant, and a mandible section. The model was then built by importing the 3D geometries from CAD software. The whole 3D model was carefully created in order to guarantee a finite element mesh that produced results adjusted to physical reality. Then, we conducted a numerical simulation using the finite element method (FEM). The results of t...
To conduct experiments under abrupt changes in g-levels, a single-engine aerobatic aircraft has b... more To conduct experiments under abrupt changes in g-levels, a single-engine aerobatic aircraft has been used, providing 6-8 seconds of reduced gravity, preceded and followed by 5-7 seconds of hypergravity periods. Due to the specific conditions of the flight and previous findings [1], the hypothesis of the present work lies on the idea that some sensory inputs could have a notorious effect on brain final responses when gravity is altered. Therefore, this study focuses on the evaluation of such hypothesis, based on the analysis of the evolution in time of intracranial activity of limbic, visual and auditory cortices. Five subjects (N=5, age 41?14 years) have flown in parabolic flight with their eyes both open and closed. Electroencephalogram signals were recorded with an Emotive Epoc headset, synchronized with a triaxial accelerometer. The intracranial brain bioelectric activity (standardized current density) throughout the parabola, was calculated by applying Standard Low Resolution Br...
Materials
In the literature, many researchers investigated static loading effects on an implant. However, d... more In the literature, many researchers investigated static loading effects on an implant. However, dynamic loading under impact loading has not been investigated formally using numerical methods. This study aims to evaluate, with 3D finite element analysis (3D FEA), the stress transferred (maximum peak and variation in time) from a dynamic impact force applied to a single implant-supported prosthesis made from different materials. A 3D implant-supported prosthesis model was created on a digital model of a mandible section using CAD and reverse engineering. By setting different mechanical properties, six implant-supported prostheses made from different materials were simulated: metal (MET), metal-ceramic (MCER), metal-composite (MCOM), carbon fiber-composite (FCOM), PEEK-composite (PKCOM), and carbon fiber-ceramic (FCCER). Three-dimensional FEA was conducted to simulate the collision of 8.62 g implant-supported prosthesis models with a rigid plate at a speed of 1 m/s after a displacemen...
Journal of the Mechanical Behavior of Biomedical Materials
The aim of this study is to evaluate the stresses transferred to peri-implant areas from single i... more The aim of this study is to evaluate the stresses transferred to peri-implant areas from single implants restored with different restorative materials and subjected to a static vertical load with low eccentricity. A total of 12 crowns were made with four types of materials: carbon fiber-composite, metal-ceramic, metal-composite, and full-metal, all of them cemented over a titanium abutment. Three different ways of approaching the problem have been used independently to verify the robustness of the conclusions. The experimental results of stress distribution around the implant were obtained by two image processing techniques: Digital Photoelasticity and Digital Image Correlation (DIC). The tests have been modelled by 3D Finite Element Method (FEM). The FEM models have also been used to study the sensitivity of the results to slight changes in geometry or loads, so that the robustness of the experimental techniques can be analyzed. In addition, the realistic bone morphology of the mandible has also been modelled by FEM, including the cortical and trabecular bone property distinctions.
Materials
Statement of problem. Previous peri-implantitis, peri-implant bone regeneration, or immediate imp... more Statement of problem. Previous peri-implantitis, peri-implant bone regeneration, or immediate implant placement postextraction may be responsible for the absence of cortical bone. Single crown materials are then relevant when dynamic forces are transferred into bone tissue and, therefore, the presence (or absence) of cortical bone can affect the long-term survival of the implant. Purpose: the purpose of this study is to assess the biomechanical response of dental rehabilitation when selecting different crown materials in models with and without cortical bone. Methods: several crown materials were considered for modeling six types of crown rehabilitation: full metal (MET), metal-ceramic (MCER), metal-composite (MCOM), peek-composite (PKCOM), carbon fiber-composite (FCOM), and carbon fiber-ceramic (FCCER). An impact-load dynamic finite-element analysis was carried out on all the 3D models of crowns mentioned above to assess their mechanical behavior against dynamic excitation. Implant...
Proceedings of the International Conference on Physiological Computing Systems, 2014
The field of physiology-based interaction and monitoring is developing at a fast pace. Emerging a... more The field of physiology-based interaction and monitoring is developing at a fast pace. Emerging applications like fatigue monitoring often use sound to convey complex dynamics of biological signals and to provide an alternative, non-visual information channel. Most Physiology-to-Sound mappings in such auditory displays do not allow customization by the end-users. We designed a new sonification system that can be used for extracting, processing and displaying Electroencephalography data (EEG) with different sonification strategies. The system was validated with four user groups performing alpha/theta neurofeedback training (a/t) for relaxation that varied in feedback personalization (Personalized/Fixed) and a number of sonified EEG features (Single/Multiple). The groups with personalized feedback performed significantly better in their training than fixed mappings groups, as shown by both subjective ratings and physiological indices. Additionally, the higher number of sonified EEG features resulted in deeper relaxation than when training with single feature feedback. Our results demonstrate the importance of adaptation and personaliziation of EEG sonification according to particular applications, in our case, to a/t neurofeedback. Our experimental approach shows how user performance can be used for validating different sonification strategies.
Over the last few decades there has been steady growth in research that addresses the real-time s... more Over the last few decades there has been steady growth in research that addresses the real-time sonification of electroencephalographic (EEG) data. Diverse application areas include medical data screening, Brain Computer Interfaces (BCI), neurofeedback, affective computing and applications in the arts. The present paper presents an overview and critical review of the principal research to date in EEG data sonification. Firstly, we identify several sub-domains of real-time EEG sonification and discuss their diverse approaches and goals. Secondly, we describe our search and inclusion criteria, and then present a synoptic summary table spanning over fifty different research projects or published research findings. Thirdly, we analyze sonification approaches to the various EEG data dimensions such as time-frequency filtering, signal level, location, before going on to consider higher order EEG features. Finally, we discuss future application domains which may benefit from new capabilities in the real-time sonification of EEG data. We believe that the present critical review may help to reduce research fragmentation and may aid future collaboration in this emerging multidisciplinary area.
Over the last few decades there has been steady growth in research that addresses the real-time s... more Over the last few decades there has been steady growth in research that addresses the real-time sonification of electroencephalographic (EEG) data. Diverse application areas include medical data screening, Brain Computer Interfaces (BCI), neurofeedback, affective computing and applications in the arts. The present paper presents an overview and critical review of the principal research to date in EEG data sonification. Firstly, we identify several sub-domains of real-time EEG sonification and discuss their diverse approaches and goals. Secondly, we describe our search and inclusion criteria, and then present a synoptic summary table spanning over fifty different research projects or published research findings. Thirdly, we analyze sonification approaches to the various EEG data dimensions such as time-frequency filtering, signal level, location, before going on to consider higher order EEG features. Finally, we discuss future application domains which may benefit from new capabilities in the real-time sonification of EEG data. We believe that the present critical review may help to reduce research fragmentation and may aid future collaboration in this emerging multidisciplinary area.
Applied sciences, Mar 19, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Healthcare
Background: In handball, the kinematics of the frontal plane seem to be one of the most important... more Background: In handball, the kinematics of the frontal plane seem to be one of the most important factors for the development of lower limb injuries. The knee valgus angle is a fundamental axis for injury prevention and is usually measured with 2D systems such as Kinovea software (Version 0.9.4.). Technological advances such as computer vision have the potential to revolutionize sports medicine. However, the validity and reliability of computer vision must be evaluated before using it in clinical practice. The aim of this study was to analyze the test-retest and inter-rater reliability and the concurrent validity of a beta version app based on computer vision for the measurement of knee valgus angle in elite handball athletes. Methods: The knee valgus angle of 42 elite handball athletes was measured. A frontal photo during a single-leg squat was taken, and two examiners measured the angle by the beta application based on computer vision at baseline and at one-week follow-up to calcu...
Journal of Clinical Medicine
Introduction: Neck pain is one of the most frequent reasons for consultation in primary care. Cli... more Introduction: Neck pain is one of the most frequent reasons for consultation in primary care. Clinicians evaluate different variables, including movement and cervical strength, to determine the prognosis of patients. Usually, the tools employed for this purpose are expensive and bulky, or more than one is needed. This study aims to describe a novel device designed to assess the cervical spine and describe its test–retest reliability. Methods: The Spinetrack device was designed to measure the strength of deep cervical flexor muscles and the chin-in and chin-out movement of the upper cervical spine. A test–retest reliability study was developed. The flexion, extension and strength needed to move the Spinetrack device were registered. Two measurements were developed, with one week between each assessment. Results: Twenty healthy subjects were evaluated. The strength of the deep cervical flexor muscles in the first measurement was 21.18 ± 3.15 Newtons, the displacement movement during c...
Mathematics
This study reports a method for the detection of mechanical signaling anomalies in cardiac tissue... more This study reports a method for the detection of mechanical signaling anomalies in cardiac tissue through the use of deep learning and the design of two anomaly detectors. In contrast to anomaly classifiers, anomaly detectors allow accurate identification of the time position of the anomaly. The first detector used a recurrent neural network (RNN) of long short-term memory (LSTM) type, while the second used an autoencoder. Mechanical contraction data present several challanges, including high presence of noise due to the biological variability in the contraction response, noise introduced by the data acquisition chain and a wide variety of anomalies. Therefore, we present a robust deep-learning-based anomaly detection framework that addresses these main issues, which are difficult to address with standard unsupervised learning techniques. For the time series recording, an experimental model was designed in which signals of cardiac mechanical contraction (right and left atria) of a C...
International Journal of Molecular Sciences
This study aimed to find the optimum mechanical characteristics of the restorative materials for ... more This study aimed to find the optimum mechanical characteristics of the restorative materials for the manufacture of implant crowns subjected to impact loading when different combinations of materials are used for the inner and outer crown. Several combinations of external–internal crown restorative materials were analyzed. The dynamic stresses at eight different zones of a dental implant subjected to an impact load and the influence of several mechanical properties, such as the Young’s modulus, Poisson’s ratio, density, and initial velocity, were analyzed and compared. A detailed 3D model was created, including the crown, the retention screw, the implant, and a mandible section. The model was then built by importing the 3D geometries from CAD software. The whole 3D model was carefully created in order to guarantee a finite element mesh that produced results adjusted to physical reality. Then, we conducted a numerical simulation using the finite element method (FEM). The results of t...
To conduct experiments under abrupt changes in g-levels, a single-engine aerobatic aircraft has b... more To conduct experiments under abrupt changes in g-levels, a single-engine aerobatic aircraft has been used, providing 6-8 seconds of reduced gravity, preceded and followed by 5-7 seconds of hypergravity periods. Due to the specific conditions of the flight and previous findings [1], the hypothesis of the present work lies on the idea that some sensory inputs could have a notorious effect on brain final responses when gravity is altered. Therefore, this study focuses on the evaluation of such hypothesis, based on the analysis of the evolution in time of intracranial activity of limbic, visual and auditory cortices. Five subjects (N=5, age 41?14 years) have flown in parabolic flight with their eyes both open and closed. Electroencephalogram signals were recorded with an Emotive Epoc headset, synchronized with a triaxial accelerometer. The intracranial brain bioelectric activity (standardized current density) throughout the parabola, was calculated by applying Standard Low Resolution Br...
Materials
In the literature, many researchers investigated static loading effects on an implant. However, d... more In the literature, many researchers investigated static loading effects on an implant. However, dynamic loading under impact loading has not been investigated formally using numerical methods. This study aims to evaluate, with 3D finite element analysis (3D FEA), the stress transferred (maximum peak and variation in time) from a dynamic impact force applied to a single implant-supported prosthesis made from different materials. A 3D implant-supported prosthesis model was created on a digital model of a mandible section using CAD and reverse engineering. By setting different mechanical properties, six implant-supported prostheses made from different materials were simulated: metal (MET), metal-ceramic (MCER), metal-composite (MCOM), carbon fiber-composite (FCOM), PEEK-composite (PKCOM), and carbon fiber-ceramic (FCCER). Three-dimensional FEA was conducted to simulate the collision of 8.62 g implant-supported prosthesis models with a rigid plate at a speed of 1 m/s after a displacemen...
Journal of the Mechanical Behavior of Biomedical Materials
The aim of this study is to evaluate the stresses transferred to peri-implant areas from single i... more The aim of this study is to evaluate the stresses transferred to peri-implant areas from single implants restored with different restorative materials and subjected to a static vertical load with low eccentricity. A total of 12 crowns were made with four types of materials: carbon fiber-composite, metal-ceramic, metal-composite, and full-metal, all of them cemented over a titanium abutment. Three different ways of approaching the problem have been used independently to verify the robustness of the conclusions. The experimental results of stress distribution around the implant were obtained by two image processing techniques: Digital Photoelasticity and Digital Image Correlation (DIC). The tests have been modelled by 3D Finite Element Method (FEM). The FEM models have also been used to study the sensitivity of the results to slight changes in geometry or loads, so that the robustness of the experimental techniques can be analyzed. In addition, the realistic bone morphology of the mandible has also been modelled by FEM, including the cortical and trabecular bone property distinctions.
Materials
Statement of problem. Previous peri-implantitis, peri-implant bone regeneration, or immediate imp... more Statement of problem. Previous peri-implantitis, peri-implant bone regeneration, or immediate implant placement postextraction may be responsible for the absence of cortical bone. Single crown materials are then relevant when dynamic forces are transferred into bone tissue and, therefore, the presence (or absence) of cortical bone can affect the long-term survival of the implant. Purpose: the purpose of this study is to assess the biomechanical response of dental rehabilitation when selecting different crown materials in models with and without cortical bone. Methods: several crown materials were considered for modeling six types of crown rehabilitation: full metal (MET), metal-ceramic (MCER), metal-composite (MCOM), peek-composite (PKCOM), carbon fiber-composite (FCOM), and carbon fiber-ceramic (FCCER). An impact-load dynamic finite-element analysis was carried out on all the 3D models of crowns mentioned above to assess their mechanical behavior against dynamic excitation. Implant...
Proceedings of the International Conference on Physiological Computing Systems, 2014
The field of physiology-based interaction and monitoring is developing at a fast pace. Emerging a... more The field of physiology-based interaction and monitoring is developing at a fast pace. Emerging applications like fatigue monitoring often use sound to convey complex dynamics of biological signals and to provide an alternative, non-visual information channel. Most Physiology-to-Sound mappings in such auditory displays do not allow customization by the end-users. We designed a new sonification system that can be used for extracting, processing and displaying Electroencephalography data (EEG) with different sonification strategies. The system was validated with four user groups performing alpha/theta neurofeedback training (a/t) for relaxation that varied in feedback personalization (Personalized/Fixed) and a number of sonified EEG features (Single/Multiple). The groups with personalized feedback performed significantly better in their training than fixed mappings groups, as shown by both subjective ratings and physiological indices. Additionally, the higher number of sonified EEG features resulted in deeper relaxation than when training with single feature feedback. Our results demonstrate the importance of adaptation and personaliziation of EEG sonification according to particular applications, in our case, to a/t neurofeedback. Our experimental approach shows how user performance can be used for validating different sonification strategies.
Over the last few decades there has been steady growth in research that addresses the real-time s... more Over the last few decades there has been steady growth in research that addresses the real-time sonification of electroencephalographic (EEG) data. Diverse application areas include medical data screening, Brain Computer Interfaces (BCI), neurofeedback, affective computing and applications in the arts. The present paper presents an overview and critical review of the principal research to date in EEG data sonification. Firstly, we identify several sub-domains of real-time EEG sonification and discuss their diverse approaches and goals. Secondly, we describe our search and inclusion criteria, and then present a synoptic summary table spanning over fifty different research projects or published research findings. Thirdly, we analyze sonification approaches to the various EEG data dimensions such as time-frequency filtering, signal level, location, before going on to consider higher order EEG features. Finally, we discuss future application domains which may benefit from new capabilities in the real-time sonification of EEG data. We believe that the present critical review may help to reduce research fragmentation and may aid future collaboration in this emerging multidisciplinary area.
Over the last few decades there has been steady growth in research that addresses the real-time s... more Over the last few decades there has been steady growth in research that addresses the real-time sonification of electroencephalographic (EEG) data. Diverse application areas include medical data screening, Brain Computer Interfaces (BCI), neurofeedback, affective computing and applications in the arts. The present paper presents an overview and critical review of the principal research to date in EEG data sonification. Firstly, we identify several sub-domains of real-time EEG sonification and discuss their diverse approaches and goals. Secondly, we describe our search and inclusion criteria, and then present a synoptic summary table spanning over fifty different research projects or published research findings. Thirdly, we analyze sonification approaches to the various EEG data dimensions such as time-frequency filtering, signal level, location, before going on to consider higher order EEG features. Finally, we discuss future application domains which may benefit from new capabilities in the real-time sonification of EEG data. We believe that the present critical review may help to reduce research fragmentation and may aid future collaboration in this emerging multidisciplinary area.