Monitoring visual attention on a neurorehabilitation environment based on interactive video

The use of new technologies in neurorehabilitation has led to higher intensity rehabilitation processes, extending therapies in an economically sustainable way. Interactive Video (IV) technology allows therapists to work with virtual environments that reproduce real situations. In this way, patients deal with Activities of the Daily Living (ADL) immersed within enhanced environments [1]. These rehabilitation exercises, which focus in re-learning lost functions, will try to modulate the neural plasticity processes [2]. This research presents a system where a neurorehabilitation IV-based environment has been integrated with an eye-tracker device in order to monitor and to interact using visual attention. While patients are interacting with the neurorehabilitation environment, their visual behavior is closely related with their cognitive state, which in turn mirrors the brain damage condition suffered by them [3] [4]. Patients’ gaze data can provide knowledge on their attention focus and their cognitive state, as well as on the validity of the rehabilitation tasks proposed [5].

Integración de tecnologías eye-tracking con vídeos interactivos para neurorrehabilitación cognitiva

La integración de las nuevas tecnologías en el proceso de rehabilitación permite la generación de terapias personalizadas, ubicuas y basadas en la evidencia. Tecnologías como el vídeo interactivo son propicias para el desarrollo de entornos virtuales en los que el paciente se ve inmerso dentro de actividades de la vida diaria en los que tiene que lograr un objetivo ecológico en un contexto seguro, controlado y adaptado a su perfil disfuncional. Dentro de este marco de rehabilitación la interacción visual paciente-entorno virtual se entiende como el mecanismo de comunicación principal, siendo además la atención visual un reflejo del estado cognitivo del paciente. El trabajo presentado en este artículo permite la integración de un sistema de eye-tracking con un entorno de neurorrehabilitación basado en vídeo interactivo. El objetivo último del sistema es la monitorización en tiempo real de la atención visual del usuario durante el proceso de neurorrehabilitación. Esta monitorización permite no sólo reproducir la ejecución de la actividad junto con el foco de la mirada, sino también detectar faltas de atención por parte del usuario, que permiten al vídeo interactivo reaccionar y adaptar la presentación de estímulos para ayudar a centrar su atención y así completar el objetivo de la actividad.

Technical evaluation of a third generation optical pose tracker for motion analysis and image-guided surgery

Laparoscopic instrument tracking systems are an essential component in image-guided interventions and offer new possibilities to improve and automate objective assessment methods of surgical skills. In this study we present our system design to apply a third generation optical pose tracker (Micron- Tracker®) to laparoscopic practice. A technical evaluation of this design is performed in order to analyze its accuracy in computing the laparoscopic instrument tip position. Results show a stable fluctuation error over the entire analyzed workspace. The relative position errors are 1.776±1.675 mm, 1.817±1.762 mm, 1.854±1.740 mm, 2.455±2.164 mm, 2.545±2.496 mm, 2.764±2.342 mm, 2.512±2.493 mm for distances of 50, 100, 150, 200, 250, 300, and 350 mm, respectively. The accumulated distance error increases with the measured distance. The instrument inclination covered by the system is high, from 90 to 7.5 degrees. The system reports a low positional accuracy for the instrument tip.

Comparative study of two laparoscopic instrument tracker designs for motion analysis and image-guided surgery: a technical evaluation

Laparoscopic instrument tracking systems are a key element in image-guided interventions, which requires high accuracy to be used in a real surgical scenario. In addition, these systems are a suitable option for objective assessment of laparoscopic technical skills based on instrument motion analysis. This study presents a new approach that improves the accuracy of a previously presented system, which applies an optical pose tracking system to laparoscopic practice. A design enhancement of the artificial markers placed on the laparoscopic instrument as well as an improvement of the calibration process are presented as a means to achieve more accurate results. A technical evaluation has been performed in order to compare the accuracy between the previous design and the new approach. Results show a remarkable improvement in the fluctuation error throughout the measurement platform. Moreover, the accumulated distance error and the inclination error have been improved. The tilt range covered by the system is the same for both approaches, from 90º to 7.5º. The relative position error is better for the new approach mainly at close distances to the camera system

Field experiment of 800× off-axis XR-Köhler concentrator module on a carousel tracker

This paper presents the design and preliminary experimental results of a concentrator-type photovoltaic module based on a free-form off-axis 800×XR-Köhler concentrator. The off-axis XR-Köhler concentrator is one of the advanced concentrators that perform high concentration with a large acceptance angle and excellent irradiance uniformity on a solar cell. As a result of on-sun characterization of the unglazed single-cell unit test rig, the temperature-corrected DC module efficiency was 32.2% at 25 °C without an anti-reflective (AR) coating on the secondary optics, and the acceptance angle was more than ±1.0°. In addition, the non-corrected DC efficiency of an individual cell in a glazed 8-cell unit module mounted on a carousel tracking system was measured. The individual efficiency deviated in the range of 24.3-27.4%, owing to the mirror shape and alignment errors. The resultant series-connected efficiency was approximately 25% at direct normal irradiation (DNI) of 770 W/m2.

Label-free biosensing for dry eye by Means of BICELLS

The use of Biophotonic Sensing Cells (BICELLs) based on micro-nano pattemed photonic architectures has been recently proven as an efficient methodology for label-free biosensing by using Optical Interrogation [1]. According to this, we have studied the different optical response for a specific typology of BICELL, consisting of structures of SU -8. This material is biocompatible with different types of biomolecules and can be immobilized on its sensing surface. In particular, we have measured the optical response for a biomarker in clinic diagnostic of dry eye. Although different proteins can be enstudied such as: PRDX5, ANXA 1, ANXA 11, CST 4, PLAA Y S 1 OOA6 related with ocular surface (dry eye), for this work PLAA (phospholipase A2) is studied by means of label free biosensing based on BICELLs for analyzing the performance and specificity according with means values of concentration in ROC curves.

A Linked Data Platform adapter for the Bugzilla issue tracker

The W3C Linked Data Platform (LDP) specification defines a standard HTTP-based protocol for read/write Linked Data and pro- vides the basis for application integration using Linked Data. This paper presents an LDP adapter for the Bugzilla issue tracker and demonstrates how to use the LDP protocol to expose a traditional application as a read/write Linked Data application. This approach provides a exible LDP adoption strategy with minimal changes to existing applications.

Evaluación de un entorno de rehabilitación cognitiva basado en tecnologías de Vídeo Interactivo y Eye-Tracking

El Daño Cerebral Adquirido (DCA) se ha convertido en una de las principales causas de discapacidad neurológica de las sociedades desarrolladas. La alteración de las funciones cognitivas como consecuencia del DCA, limita no sólo la calidad de vida del paciente sino también la de las persona de su entorno. Aunque la neurorrehabilitación permite recuperar algunas de las funciones alteradas aprovechando la naturaleza plástica del sistema nervioso, su práctica siguiendo procesos tradicionales no permiten en muchos casos ajustarse a las necesidades de cada individuo ni, en general, cubrir todos los aspectos necesarios que conviertan al proceso rehabilitador en un tratamiento realmente efectivo. La incorporación al proceso de rehabilitación de las nuevas tecnologías ha permitido aumentar la intensidad del tratamiento, personalizando y prolongándolo en el tiempo de forma sostenible. Los entornos virtuales (EV) apoyados en esta tendencia permiten reproducir Actividades de Vida Diaria (AVD) controladas que incrementan el valor ecológico de las terapias. Este Trabajo Fin de Grado aborda el uso pionero de la tecnología de Vídeo Interactivo (VI) para el desarrollo de dichos entornos en el campo de la rehabilitación cognitiva. En concreto, el objetivo del TFG es la evaluación de un EV de rehabilitación desarrollado mediante tecnología de VI e integrado con un sistema de Eye-Tracking, capaz de capturar y analizar la información referente al comportamiento visual del paciente. Para este fin, se realiza el diseño, implementación y evaluación de un estudio experimental que registre el comportamiento de diferentes sujetos ante dos modalidades de AVD.