Contribuciones al uso de marcadores para Navegación Autónoma y Realidad Aumentada

Square planar markers are a widely used tools for localization and tracking due to their low cost and high performance. Many applications in Robotics, Unmanned Vehicles and Augmented Reality employ these markers for camera pose estimation with high accuracy. Nevertheless, marker-based systems are affected by several factors that limit their performance. First, the marker detection process is a time-consuming task, which is intensified as the image size increases. As a consequence, the current high-resolution cameras has weakened the processing efficiency of traditional marker systems. Second, marker detection is affected by the presence of noise, blurring and occlusion. The movement of the camera produces image blurriness, generated even by small movements. Furthermore, the marker may be partially or completely occluded in the image, so that it is no longer detected. This thesis deals with the above limitations, proposing novel methodologies and strategies for successful marker detection improving both the efficiency and robustness of these systems. First, a novel multi-scale approach has been developed to speed up the marker detection process. The method takes advantage of the different resolutions at which the image is represented to predict at runtime the optimal scale for detection and identification, as well as following a corner upsampling strategy necessary for an accurate pose estimation. Second, we introduce a new marker design, Fractal Marker, which using a novel keypoint-based method achieves detection even under severe occlusion, while allowing detection over a wider range of distance than traditional markers. Finally, we propose a new marker detection strategy based on Discriminative Correlation Filters (DCF), where the marker and its corners represented in the frequency domain perform more robust and faster detections than state-ofthe- art methods, even under extreme blur conditions.Los marcadores planos cuadrados son una de las herramientas ampliamente utilizadas para la localización y el tracking debido a su bajo coste y su alto rendimiento. Muchas aplicaciones en Robótica, Vehículos no Tripulados y Realidad Aumentada emplean estos marcadores para estimar con alta precisión la posición de la cámara. Sin embargo, los sistemas basados en marcadores se ven afectados por varios factores que limitan su rendimiento. En primer lugar, el proceso de detección de marcadores es una tarea que requiere mucho tiempo y este incrementa a medida que aumenta el tamaño de la imagen. En consecuencia, las actuales cámaras de alta resolución han debilitado la eficacia del procesamiento de los sistemas de marcadores tradicionales. Por otra parte, la detección de marcadores se ve afectada por la presencia de ruido, desenfoque y oclusión. El movimiento de la cámara produce desenfoque de la imagen, generado incluso por pequeños movimientos. Además, el marcador puede aparecer en la imagen parcial o completamente ocluido, dejando de ser detectado. Esta tesis aborda las limitaciones anteriores, proponiendo metodologías y estrategias novedosas para la correcta detección de marcadores, mejorando así tanto la eficiencia como la robustez de estos sistemas. En primer lugar, se ha desarrollado un novedoso enfoque multiescala para acelerar el proceso de detección de marcadores. El método aprovecha las diferentes resoluciones en las que la imagen está representada para predecir en tiempo de ejecución la escala óptima para la detección e identificación, a la vez que sigue una estrategia de upsampling de las esquinas necesaria para estimar la pose con precisión. En segundo lugar, introducimos un nuevo diseño de marcador, Fractal Marker, que, mediante un método basado en keypoints, logra detecciones incluso en casos de oclusión extrema, al tiempo que permite la detección en un rango de distancias más amplio que los marcadores tradicionales. Por último, proponemos una nueva estrategia de detección de marcadores basada en Discriminate Correlation Filters (DCF), donde el marcador y sus esquinas representadas en el dominio de la frecuencia realizan detecciones más robustas y rápidas que los métodos de referencia, incluso bajo condiciones extremas de emborronamiento

sSLAM: Speeded-Up Visual SLAM Mixing Artificial Markers and Temporary Keypoints

Environment landmarks are generally employed by visual SLAM (vSLAM) methods in the form of keypoints. However, these landmarks are unstable over time because they belong to areas that tend to change, e.g., shadows or moving objects. To solve this, some other authors have proposed the combination of keypoints and artificial markers distributed in the environment so as to facilitate the tracking process in the long run. Artificial markers are special elements (similar to beacons) that can be permanently placed in the environment to facilitate tracking. In any case, these systems keep a set of keypoints that is not likely to be reused, thus unnecessarily increasing the computing time required for tracking. This paper proposes a novel visual SLAM approach that efficiently combines keypoints and artificial markers, allowing for a substantial reduction in the computing time and memory required without noticeably degrading the tracking accuracy. In the first stage, our system creates a map of the environment using both keypoints and artificial markers, but once the map is created, the keypoints are removed and only the markers are kept. Thus, our map stores only long-lasting features of the environment (i.e., the markers). Then, for localization purposes, our algorithm uses the marker information along with temporary keypoints created just in the time of tracking, which are removed after a while. Since our algorithm keeps only a small subset of recent keypoints, it is faster than the state-of-the-art vSLAM approaches. The experimental results show that our proposed sSLAM compares favorably with ORB-SLAM2, ORB-SLAM3, OpenVSLAM and UcoSLAM in terms of speed, without statistically significant differences in accuracy

sSLAM: Speeded-Up Visual SLAM Mixing Artificial Markers and Temporary Keypoints

Environment landmarks are generally employed by visual SLAM (vSLAM) methods in the form of keypoints. However, these landmarks are unstable over time because they belong to areas that tend to change, e.g., shadows or moving objects. To solve this, some other authors have proposed the combination of keypoints and artificial markers distributed in the environment so as to facilitate the tracking process in the long run. Artificial markers are special elements (similar to beacons) that can be permanently placed in the environment to facilitate tracking. In any case, these systems keep a set of keypoints that is not likely to be reused, thus unnecessarily increasing the computing time required for tracking. This paper proposes a novel visual SLAM approach that efficiently combines keypoints and artificial markers, allowing for a substantial reduction in the computing time and memory required without noticeably degrading the tracking accuracy. In the first stage, our system creates a map of the environment using both keypoints and artificial markers, but once the map is created, the keypoints are removed and only the markers are kept. Thus, our map stores only long-lasting features of the environment (i.e., the markers). Then, for localization purposes, our algorithm uses the marker information along with temporary keypoints created just in the time of tracking, which are removed after a while. Since our algorithm keeps only a small subset of recent keypoints, it is faster than the state-of-the-art vSLAM approaches. The experimental results show that our proposed sSLAM compares favorably with ORB-SLAM2, ORB-SLAM3, OpenVSLAM and UcoSLAM in terms of speed, without statistically significant differences in accuracy.This research was funded by the project PID2019-103871GB-I00 of the Spanish Ministry of Economy, Industry and Competitiveness, FEDER, Project 1380047-F UCOFEDER-2021 of Andalusia and by the European Union–NextGeneration EU for requalification of Spanish University System 2021–2023

Diffusion in a class of exactly solvable non-harmonic potentials. Intrinsic effects induced by non-linearities

This paper deals with the problem of a particle that diffuses in a potential with a reflecting barrier and has a point of stable equilibrium and a point of unstable equilibrium. Based on the exact solutions obtained earlier for the Fokker-Planck equation of a class of these models, we analyze the behavior of the probability density, the mean path and the onset time which determines the transition from unimodal to bimodal probability densities. The study is made over different initial positions, two of them very close to the unstable point, which permits a clear comparison among the subsequent evolutions, and the observation of some intrinsic effects induced by non-linearities

Effects of a cocoa diet on an intestinal inflammation model in rats

Cocoa is a rich source of fiber and flavonoids with recognized antioxidant and anti-inflammatory potential. The aim of this study was to evaluate the effects of a cocoa-enriched diet on rats with dextran sulphate sodium (DSS)-induced colitis. Wistar rats were fed with either a 5% cocoa diet or standard diet. Colon inflammation was induced by DSS in the drinking water: 5% for 6 days and 2% over the following 9 days. Colitis was assessed by body weight loss, stool consistency and blood presence in stools. A group of animals fed standard diet was treated with quercitrin (1 mg/kg) after colitis establishment. After 2 weeks of DSS treatment, the colon oxidative and inflammatory status and lymphocyte composition from blood and mesenteric lymph nodes (MLN) were assessed. The cocoa-fed group did not exhibit amelioration of clinical colitis but displayed higher antioxidant activity than the colitic reference group by the restoration of colon glutathione content and prevention of lipid peroxidation. The cocoa diet showed anti-inflammatory potential because it down-regulated serum TNF-alpha, colon iNOS activity and decreased colon cell infiltration. Lymphocyte composition in MLN was not modified by drinking DSS, but there was an increase in the proportion of NK and regulatory T cells in the blood. These changes were not modified by cocoa. In conclusion, cocoa intake may help to inhibit the negative oxidative effects consequent to colitis, although this action is not enough to abrogate the intestinal inflammation significantly

Cord blood-derived CD34+ hematopoietic cells with low mitochondrial mass are enriched in hematopoietic repopulating stem cell function

This work was funded by the CICE/FEDER (P08-CTS-3678) de la Junta de Andalucia with a grant to PM, the FIS/FEDER (PI10/00449 to PM and PI11/00119 to CB), the MICINN (Fondo Especial del Estado para Dinamizacion de la Economia y Empleo/PLE-2009-0111) with a grant to PM, and the Foundation "Spanish Association Against Cancer"/Junta Provincial de Albacete (CI110023 to PM). DRM (PFIS scholarship FI11/0511), RM and CB (CP07/0059) are supported by the ISCIII. ON-M was supported by the Health of Department of the Junta de Andalucia.The homeostasis of the hematopoietic stem/progenitor cell pool relies on a fine-tuned balance between self-renewal, differentiation and proliferation. Recent studies have proposed that mitochondria regulate these processes. Although recent work has contributed to understanding the role of mitochondria during stem cell differentiation, it remains unclear whether the mitochondrial content/function affects human hematopoietic stem versus progenitor function. We found that mitochondrial mass correlates strongly with mitochondrial membrane potential in CD34(+) hematopoietic stem/progenitor cells. We, therefore, sorted cord blood CD34(+) cells on the basis of their mitochondrial mass and analyzed the in vitro homeostasis and clonogenic potential as well as the in vivo repopulating potential of CD34(+) cells with high (CD34(+) Mito(High)) versus low (CD34(+) Mito(Low)) mitochondrial mass. The CD34(+) Mito(Low) fraction contained 6-fold more CD34(+)CD38(-) primitive cells and was enriched in hematopoietic stem cell function, as demonstrated by its significantly greater hematopoietic reconstitution potential in immuno deficient mice. In contrast, the CD34(+) Mito(High) fraction was more enriched in hematopoietic progenitor function with higher in vitro clonogenic capacity. In vitro differentiation of CD34(+) Mito(Low) cells was significantly delayed as compared to that of CD34(+) Mito(High) cells. The eventual complete differentiation of CD34(+) Mito(Low) cells, which coincided with a robust expansion of the CD34(-) differentiated progeny, was accompanied by mitochondrial adaptation, as shown by significant increases in ATP production and expression of the mitochondrial genes ND1 and COX2. In conclusion, cord blood CD34(+) cells with low levels of mitochondrial mass are enriched in hematopoietic repopulating stem cell function whereas high levels of mitochondrial mass identify hematopoietic progenitors. A mitochondrial response underlies hematopoietic stem/progenitor cell differentiation and proliferation of lineage-committed CD34(-) cells.Junta de Andalucia P08-CTS-3678European Union (EU) Instituto de Salud Carlos III PI10/00449 PI11/00119MICINN (Fondo Especial del Estado para Dinamizacion de la Economia y Empleo) PLE-2009-0111Foundation "Spanish Association Against Cancer"/Junta Provincial de Albacete CI110023Instituto de Salud Carlos III FI11/0511 CP07/0059ICRE

Cocaine promotes oxidative stress and microglial-macrophage activation in rat cerebellum

Different mechanisms have been suggested for cocaine neurotoxicity, including oxidative stress alterations. Nuclear factor kappa B (NF-κB), considered a sensor of oxidative stress and inflammation, is involved in drug toxicity and addiction. NF-κB is a key mediator for immune responses that induces microglial/macrophage activation under inflammatory processes and neuronal injury/degeneration. Although cerebellum is commonly associated to motor control, muscular tone, and balance. Its relation with addiction is getting relevance, being associated to compulsive and perseverative behaviors. Some reports indicate that cerebellar microglial activation induced by cannabis or ethanol, promote cerebellar alterations and these alterations could be associated to addictive-related behaviors. After considering the effects of some drugs on cerebellum, the aim of the present work analyzes pro-inflammatory changes after cocaine exposure. Rats received daily 15 mg/kg cocaine i.p., for 18 days. Reduced and oxidized forms of glutathione (GSH) and oxidized glutathione (GSSG), glutathione peroxidase (GPx) activity and glutamate were determined in cerebellar homogenates. NF-κB activity, CD68, and GFAP expression were determined. Cerebellar GPx activity and GSH/GSSG ratio are significantly decreased after cocaine exposure. A significant increase of glutamate concentration is also observed. Interestingly, increased NF-κB activity is also accompanied by an increased expression of the lysosomal mononuclear phagocytic marker ED1 without GFAP alterations. Current trends in addiction biology are focusing on the role of cerebellum on addictive behaviors. Cocaine-induced cerebellar changes described herein fit with previosus data showing cerebellar alterations on addict subjects and support the proposed role of cerebelum in addiction

UCO physical rehabilitation: new dataset and study of human pose estimation methods on physical rehabilitation exercises

Physical rehabilitation plays a crucial role in restoring motor function following injuries or surgeries. However, the challenge of overcrowded waiting lists often hampers doctors’ ability to monitor patients’ recovery progress in person. Deep Learning methods offer a solution by enabling doctors to optimize their time with each patient and distinguish between those requiring specific attention and those making positive progress. Doctors use the flexion angle of limbs as a cue to assess a patient’s mobility level during rehabilitation. From a Computer Vision perspective, this task can be framed as automatically estimating the pose of the target body limbs in an image. The objectives of this study can be summarized as follows: (i) evaluating and comparing multiple pose estimation methods; (ii) analyzing how the subject’s position and camera viewpoint impact the estimation; and (iii) determining whether 3D estimation methods are necessary or if 2D estimation suffices for this purpose. To conduct this technical study, and due to the limited availability of public datasets related to physical rehabilitation exercises, we introduced a new dataset featuring 27 individuals performing eight diverse physical rehabilitation exercises focusing on various limbs and body positions. Each exercise was recorded using five RGB cameras capturing different viewpoints of the person. An infrared tracking system named OptiTrack was utilized to establish the ground truth positions of the joints in the limbs under study. The results, supported by statistical tests, show that not all state-of-the-art pose estimators perform equally in the presented situations (e.g., patient lying on the stretcher vs. standing). Statistical differences exist between camera viewpoints, with the frontal view being the most convenient. Additionally, the study concludes that 2D pose estimators are adequate for estimating joint angles given the selected camera viewpoints

Bypass subclavio-axilar derecho por herida de arma de fuego

El trauma torácico es común en los pacientes politraumatizados, mas aun, en los heridos por arma de fuego, la identificación de la gravedad de las lesiones, y la habilidad para resolverlas de manera oportuna, sumadas a la disponibilidad de recursos, determina la sobrevida en estos pacientes. Presentamos el caso de un paciente de 19 años que ingresó a nuestro hospital con una herida de proyectil de arma de fuego, a nivel facial-cevical-torácico, con compromiso vascular arterio-venoso subclavio derecho, asociado a lesión pulmonar, el cual pudo ser resuelto quirúrgicamente de manera exitosa en nuestra institución, con evolución favorable y seguimiento a un año sin secuelas.Facultad de Ciencias Médica

FICARAM-15 Cruise Report 20th March – 22nd May 2013 on board BIO Hespérides by the Group FICARAM

54 páginas, 19 figuras, 3 anexosThe FICARAM-15 is the fifteenth repetition of a section conducted in 1994. This section is part of the international program GOSHIP (http://www.go-ship.org/CruisePlans.html) to develop a globally coordinated network of sustained hydrographic sections as part of the global ocean/climate observing system. The objective of the FICARAM-15 cruise is to investigate the temporal evolution of the anthropogenic carbon and evaluate the CO2 absorption capacity of the South Atlantic region, the Equatorial zone, and the subtropical region of Azores-Gibraltar in the North Atlantic. This cruise is supported by the CATARINA project funded by the Ministry of Economy and Competitiveness (CTM2010-17141) and is part of the European Union FP7 project CARBOCHANGE (http://carbochange.b.uib.no/). The objective of FICARAM-15 cruise is framed in the CATARINA project conducted by the tasks I.2.1 (air-sea CO2 exchange) I.3 (ventilation of water masses), I.4.1 (zonal variability of N2O and CH4), I.4.2 (anthropogenic carbon storage), I.4.4 (saturation horizon of calcium carbonate along the section) and I.5.4 (evolution of the acidification rates). Another component of the FICARAM-15 cruise aims to examine the biological and biogeochemical mechanisms that hinder total dissolved organic carbon (DOC) remineralisation in marine systems, taking a multidisciplinary perspective and applying many different approaches. This is the global objective of the Spanish project DOREMI (CTM2012-34294) that joins this FICARAM-15 cruise.During the FICARAM cruise the physical oceanography group was responsible for collecting the following data sets: CTD and XBT data; vessel-mounted ADCP and lowered ADCP; continuous thermosalinograph. Physical oceanographers participated in the cruise financed through Project “Tipping Corners in the Meridional Overturning Circulation” (TIC-MOC), CTM2011-28867. The FICARAM-15 cruise was organized in two phases with a common sampling. LEG 1: From Punta Arenas (Chile) to Recife (Brazil): 62 stations. Chief Scientist: Aida F. Ríos, PI of CATARINA project LEG 2: From Recife (Brazil) to Cartagena (Spain): 46 stations Chief Scientist: Celia Marrasé, PI of DOREMI project This report contains the sampling of all the variables at each station along the FICARAM section, as well as the analysis of the biogeochemical variables and the preliminary results. The principal investigator of the DOREMI project produced another report with the common sampling section, showing the analysis and results of the experiments on dissolved organic matter carried out on board.This cruise is supported by the CATARINA project funded by the Ministry of Economy and Competitiveness (CTM2010-17141) and is part of the European Union FP7 project CARBOCHANGE (http://carbochange.b.uib.no/)Peer reviewe