Herramienta de Soporte para la Evaluación Subjetiva de la Usabilidad Mediante el Método Microsoft Reaction Cards

Este Trabajo Fin de Grado consiste en el desarrollo de una métrica cuantitativa para la evaluación comparativa de la usabilidad percibida por los usuarios (usabilidad subjetiva) a través del método Reaction Cards, además de una herramienta de soporte para llevar a cabo dicha evaluación, con el objetivo de poder realizar y comparar distintas evaluaciones, añadiendo una valoración numérica a cada evaluación. Reaction Cards es un método para medir la satisfacción del usuario, y este es un aspecto fundamental a la hora de realizar un análisis de usabilidad, por lo que es necesario poder comparar evaluaciones y establecer umbrales que permitan determinar qué solución es mejor. El método de Reaction Cards consiste en solicitar al usuario que seleccione entre 118 tarjetas con adjetivos aquellas que representan su experiencia con la aplicación, ampliando luego el análisis a obtener comentarios de las cinco tarjetas más representativas. Para interpretar estos resultados, en estudios anteriores se han dividido las tarjetas entre positivas y negativas. En este trabajo, se ha encontrado que la mejor forma de obtener una valoración numérica de cada tarjeta ha sido realizar un estudio con 55 sujetos para que valorasen cada tarjeta entre 1 (muy negativo) y 5 (muy positivo). La media acotada de la opinión de todos los sujetos es la puntuación asociada a cada tarjeta, y finalmente la puntuación final de la evaluación se forma como la suma de puntuaciones de las tarjetas seleccionadas entre la puntuación máxima con ese número de tarjetas, multiplicado por 100. La herramienta desarrollada es una herramienta web que permite el registro e inicio de sesión de usuarios. Cada usuario puede crear sus propios estudios (de los que es propietario), indicando la categoría, el nombre de la aplicación, el sistema operativo y la versión del mismo. Los usuarios ven los estudios de los que son propietarios, pudiendo añadir nuevas evaluaciones o acceder al detalle de los mismos y ver las evaluaciones realizadas con los comentarios recogidos. La herramienta proporciona además un sistema que permite comparar distintas evaluaciones de forma visual, mediante gráficas y nubes de palabras. El desarrollo se ha realizado en HTML/CSS/JavaScript para la vista, PHP para el controlador, y SQL para el modelo. La herramienta muestra las ventanas en el navegador, siendo páginas dinámicas que se generan en PHP en el servidor web, accediendo a la información del modelo contenido en una base de datos MySQL. Sobre la herramienta, se han realizado pruebas de usabilidad, en las que han participado 10 sujetos y ha permitido ver que la herramienta cumple con requisitos de facilidad de uso y de aprendizaje. En conclusión, se ha realizado una herramienta que permite gestionar y realizar estudios de usabilidad, aportando una puntuación numérica a cada evaluación de manera que se pueden comparar más fácilmente dos soluciones distintas, todo ello bajo la premisa de la facilidad de uso.This Bachelor Thesis consists in the development of a quantitative metric for the comparative evaluation of the usability perceived by users (subjective usability) through the Reaction Cards method, as well as a support tool to carry out that evaluation, in order to be able to make and to compare different assessments, by adding a numerical rating to each assessment. Reaction Cards is a method to measure user’s satisfaction, and this is a main aspect to consider when you are making a usability analysis, so it’s necessary to compare assessments and determine thresholds to see which solution is better. Reaction Cards method consists in showing the user a set of 118 cards, and encourage him to pick the cards that represents more his experience with the application, obtaining more comments from the user asking him about the five most representative cards. Previous studies have divided the cards between positive and negative to interpret these findings. However, in this thesis we found that the best way to obtain a numerical rating for each card has been doing a small study with 55 subjects in which the subjects select a rating for each card from 1 (very negative) to 5 (very positive). The average opinion of all subjects is the rating associated to each card, and finally the final score of an assessment is the sum of the ratings of selected cards, divided by the maximum score with that number of cards, multiplied by 100. Developed tool is a web application that allows user registration and login. Each user can create his own studies, which he is the owner, introducing category, application name, operating system and version. Users can see the detail of the studies of their own, and they can add new assessments or look at the comments received in previous assessments. The tool also gives a system that allows comparing different assessments in a visual way, using plots and word clouds. Development has been realized in HTML/CSS/JavaScript for the view, PHP for the controller and SQL for the model. The tool shows the interface in an explorer, each interface is a dynamic page generated by PHP in the web server, using the data allocated in a MySQL database. For testing, a usability testing has been performed, realized by 10 subjects, and this test has allowed to check that the tool complies with the ease of use and learning requisites, and has to improve in perceived usefulness. In conclusion, the developed tool allows to manage and realize usability studies, giving a numerical rating to each assessment and allowing to compare different evaluations easily, with an ease of use

Robust 3D People Tracking and Positioning System in a Semi-Overlapped Multi-Camera Environment

People positioning and tracking in 3D indoor environments are challenging tasks due to background clutter and occlusions. Current works are focused on solving people occlusions in low-cluttered backgrounds, but fail in high-cluttered scenarios, specially when foreground objects occlude people. In this paper, a novel 3D people positioning and tracking system is presented, which shows itself robust to both possible occlusion sources: static scene objects and other people. The system holds on a set of multiple cameras with partially overlapped fields of view. Moving regions are segmented independently in each camera stream by means of a new background modeling strategy based on Gabor filters. People detection is carried out on these segmentations through a template-based correlation strategy. Detected people are tracked independently in each camera view by means of a graph-based matching strategy, which estimates the best correspondences between consecutive people segmentations. Finally, 3D tracking and positioning of people is achieved by geometrical consistency analysis over the tracked 2D candidates, using head position (instead of object centroids) to increase robustness to foreground occlusions

Gradient induced artifacts in simultaneous EEG-fMRI: Effect of synchronization on spiral and EPI k-space trajectories

The nature of the gradient induced electroencephalography (EEG) artifact is analyzed and compared for two functional magnetic resonance imaging (fMRI) pulse sequences with different k-space trajectories: echo planar imaging (EPI) and spiral. Furthermore, the performance of the average artifact subtraction algorithm (AAS) to remove the gradient artifact for both sequences is evaluated. The results show that the EEG gradient artifact for spiral sequences is one order of magnitude higher than for EPI sequences due to the chirping spectrum of the spiral sequence and the dB/dt of its crusher gradients. However, in the presence of accurate synchronization, the use of AAS yields the same artifact suppression efficiency for both pulse sequences below 80 Hz. The quality of EEG signal after AAS is demonstrated for phantom and human data. EEG spectrogram and visual evoked potential (VEP) are compared outside the scanner and use both EPI and spiral pulse sequences. MR related artifact residues affect the spectra over 40 Hz (less than 0.2 μV up to 120 Hz) and modify the amplitude of P1, N2 and P300 in the VEP. These modifications in the EEG signal have to be taken into account when interpreting EEG data acquired in simultaneous EEG-fMRI experiments

Color-based 3D particle filtering for robust tracking in heterogeneous environments

Most multi-camera 3D tracking and positioning systems rely on several independent 2D tracking modules applied over individual camera streams, fused using both geometrical relationships across cameras and/or observed appearance of objects. However, 2D tracking systems suffer inherent difficulties due to point of view limitations (perceptually similar foreground and background regions causing fragmentation of moving objects, occlusions, etc.) and, therefore, 3D tracking based on partially erroneous 2D tracks are likely to fail when handling multiple-people interaction. In this paper, we propose a Bayesian framework for combining 2D low-level cues from multiple cameras directly into the 3D world through 3D Particle Filters. This novel method (direct 3D operation) allows the estimation of the probability of a certain volume being occupied by a moving object, using 2D motion detection and color features as state observations of the Particle Filter framework. For this purpose, an efficient color descriptor has been implemented, which automatically adapts itself to image noise, proving able to deal with changes in illumination and shape variations. The ability of the proposed framework to correctly track multiple 3D objects over time is tested on a real indoor scenario, showing satisfactory results

Real-time Surveillance Application by Multiple Detectors and Compressive Trackers

A real-time surveillance system for IP network cameras is presented. Motion, part-body, and whole-body detectors are efficiently combined to generate robust and fast detections, which feed multiple compressive trackers. The generated trajectories are then improved using a reidentification strategy for long term operation

Circulating Cell Biomarkers in Pulmonary Arterial Hypertension: Relationship with Clinical Heterogeneity and Therapeutic Response

Biomarcadores; Disfunción endotelial; Células progenitorasBiomarcadors; Disfunció endotelial; Cèl·lules progenitoresBiomarkers; Endothelial dysfunction; Progenitor cellsBackground: Endothelial dysfunction is central to PAH. In this study, we simultaneously analysed circulating levels of endothelial microvesicles (EMVs) and progenitor cells (PCs) in PAH and in controls, as biomarkers of pulmonary endothelial integrity and evaluated differences among PAH subtypes and as a response to treatment. Methods: Forty-seven controls and 144 patients with PAH (52 idiopathic, 9 heritable, 31 associated with systemic sclerosis, 15 associated with other connective tissue diseases, 20 associated with HIV and 17 associated with portal hypertension) were evaluated. Forty-four patients with scleroderma and 22 with HIV infection, but without PAH, were also studied. Circulating levels of EMVs, total (CD31+CD42b−) and activated (CD31+CD42b−CD62E+), as well as circulating PCs (CD34+CD133+CD45low) were measured by flow cytometry and the EMVs/PCs ratio was computed. In treatment-naïve patients, measurements were repeated after 3 months of PAH therapy. Results: Patients with PAH showed higher numbers of EMVs and a lower percentage of PCs, compared with healthy controls. The EMV/PC ratio was increased in PAH patients, and in patients with SSc or HIV without PAH. After starting PAH therapy, individual changes in EMVs and PCs were variable, without significant differences being observed as a group. Conclusion: PAH patients present disturbed vascular homeostasis, reflected in changes in circulating EMV and PC levels, which are not restored with PAH targeted therapy. Combined measurement of circulating EMVs and PCs could be foreseen as a potential biomarker of endothelial dysfunction in PAH.This research was funded by grants PI12/00510, PI15/00582 and PI18/00960 from the Institute of Health Carlos III (ISCiii), Spain, co-funded by the European Union (ERDF/ESF); the Catalan Society of Respiratory Medicine (SOCAP); and the Fundación Contra la Hipertensión Pulmonar (FCHP). OTC is the former recipient of a Marie Curie Post-Doctoral Fellowship Award BIOTRACK-IDIBAPS, and the current recipient of a Miguel Servet contract from ISCiii (CP17/00114)

Disparate connectivity for structural and functional networks is revealed when physical location of the connected nodes is considered

Macroscopic brain networks have been widely described with the manifold of metrics available using graph theory. However, most analyses do not incorporate information about the physical position of network nodes. Here, we provide a multimodal macroscopic network characterization while considering the physical positions of nodes. To do so, we examined anatomical and functional macroscopic brain networks in a sample of twenty healthy subjects. Anatomical networks are obtained with a graph based tractography algorithm from diffusion-weighted magnetic resonance images (DW-MRI). Anatomical con- nections identified via DW-MRI provided probabilistic constraints for determining the connectedness of 90 dif- ferent brain areas. Functional networks are derived from temporal linear correlations between blood-oxygenation level-dependent signals derived from the same brain areas. Rentian Scaling analysis, a technique adapted from very- large-scale integration circuits analyses, shows that func- tional networks are more random and less optimized than the anatomical networks. We also provide a new metric that allows quantifying the global connectivity arrange- ments for both structural and functional networks. While the functional networks show a higher contribution of inter-hemispheric connections, the anatomical networks highest connections are identified in a dorsal?ventral arrangement. These results indicate that anatomical and functional networks present different connectivity organi- zations that can only be identified when the physical locations of the nodes are included in the analysis

Anatomo-functional organization in brain networks

There are several studies focused on comparing rsFC networks with their structural substrate \cite{hagmann2008, honey2010}. However an accurate description of how anatomo-­functional connections are organized, both at physical and topological levels, is still to be defined. Here we present an approach to quantify the anatomo-functional organization and discuss its consistency

Derivation and validation of a blood biomarker score for 2-day mortality prediction from prehospital care: a multicenter, cohort, EMS-based study

Producción CientíficaIdentifying potentially life-threatening diseases is a key challenge for emergency medical services. This study aims at examining the role of different prehospital biomarkers from point-of-care testing to derive and validate a score to detect 2-day in-hospital mortality. We conducted a prospective, observational, prehospital, ongoing, and derivation—validation study in three Spanish provinces, in adults evacuated by ambulance and admitted to the emergency department. A total of 23 ambulance-based biomarkers were collected from each patient. A biomarker score based on logistic regression was fitted to predict 2-day mortality from an optimum subset of variables from prehospital blood analysis, obtained through an automated feature selection stage. 2806 cases were analyzed, with a median age of 68 (interquartile range 51–81), 42.3% of women, and a 2-day mortality rate of 5.5% (154 non-survivors). The blood biomarker score was constituted by the partial pressure of carbon dioxide, lactate, and creatinine. The score fitted with logistic regression using these biomarkers reached a high performance to predict 2-day mortality, with an AUC of 0.933 (95% CI 0.841–0.973). The following risk levels for 2-day mortality were identified from the score: low risk (score < 1), where only 8.2% of non-survivors were assigned to; medium risk (1 ≤ score < 4); and high risk (score ≥ 4), where the 2-day mortality rate was 57.6%. The novel blood biomarker score provides an excellent association with 2-day in-hospital mortality, as well as real-time feedback on the metabolic-respiratory patient status. Thus, this score can help in the decision-making process at critical moments in life-threatening situations.Junta de Castilla y León (Gerencia Regional de Salud - grant number GRS 1903/A/19 and GRS 2131/A/20)Ministerio de Ciencia e Innovación/Agencia Estatal de Investigación/10.13039/501100011033/’, ERDF A way of making Europe, and Next GenerationEU/PRTR (under projects PID2020-115468RB-I00 and PDC2021-120775-I00)CIBER -Consorcio Centro de Investigación Biomédica en Red (Instituto de Salud Carlos III) (CB19/01/00012)Publicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCL

Small molecule anion transporters display in vitro antimicrobial activity against clinically relevant bacterial strains

Highly active transmembrane anion transporters have demonstrated their activity against antibiotic-resistant and clinically relevant bacterial strains. This type of compound offers promise as a strategy to develop novel antibacterial agents