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Tesi amb menció internacional, A la portada: Centre for Sensors, Instruments and Systems Development (CD6-UPC). Faculty of Optics and Optometry of Terrassa (FOOT), (English) Polarization is one of the properties of light and it is often put aside. Human beings receive light beams and process only the intensity and wavelength information. Our optical system lacks the capability of ’seeing’ polarization in comparison to other animals. The vectorial nature of polarization is uncorrelated to the intensity and colour information and this can unveil additional information for improving the current technology. This Thesis aims to develop a camera capable of measuring the full polarization in a 2D scene. In particular, it focuses on the design and construction of a prototype that measures in the visible waveband the full-Stokes vector in a snapshot such that the acquisition time and noise equalization are balanced while reducing movement and registration artefacts. The Thesis starts with the revision of the current state of the art in the polarimetric imaging field. Based on this, the optomechanical design of the polarimetric camera is developed ensuring a faster acquisition of polarization since it integrates optimum states to immunize the system from Gaussian and Poisson noise. Accordingly, this Thesis proposes a general calibration methodology addressed to the radiometry of the sensor, the geometrical aberrations from optics and the polarization elements in the system to transform the intensity measurements into polarization information. Besides, this Thesis studies two imaging modes of polarization, Stokes imaging and Mueller matrix imaging, for different applications. The novelty of this system consists of the use of optimal polarization states in a division of aperture architecture for noise immunization. Finally, this Thesis studies the application of the system to improve detection in the real-world problem of seeing through the fog. Polarization information can improve the range of detection due to the polarization memory effect. This system could be employed inside a multimodal system to ensure detection when others are hamp, (Català) La polarització és una de les propietats de la llum i que sovint es prescindeix d’ella. Els éssers humans reben els raigs de llum i únicament processen la informació provinent de la intensitat i la longitud d’ona de la llum. El nostre sistema òptic no té la capacitat de "veure" la polarització en comparació a altres animals. La natura vectorial de la polarització està no correlada amb la informació donada per la intensitat i el color, i això pot revelar informació addicional per millorar la tecnologia actual. Aquesta Tesi té com a objectiu desenvolupar una càmera per mesurar la polarització d’una escena 2D. En particular, es centra en el disseny i construcció d’un prototip que mesuri a l’espectre visible el vector de Stokes complert en un sol tret de manera que el temps d’adquisició i la equalització del soroll siguin compensats a la vegada que es redueixen els artefactes causats pel moviment i pel registre. La Tesi comença revisant l’actual estat de l’art en el camp de la imatge polarimètrica. Arran d’això, es realitza el disseny optomecànic de la càmera polarimètrica garantint una adquisició ràpida, ja que el disseny implementa uns estats òptims de polarització per immunitzar el sistema de soroll gaussià i de Poisson. Per tant, aquesta Tesi proposa una metodologia general de calibratge dirigida a la radiometria del sensor, a les aberracions geomètriques de l’òptica i als elements de polarització en el sistema per transformar les mesures d’intensitat en informació polarimétrica. A més, aquesta Tesi estudia dos maneres d’imatge de la polarització, imatge de Stokes i imatge de la matriu de Mueller, per diferents aplicacions. La novetat d’aquest sistema radica en la utilització d’estats de polarització òptims basant-se en una arquitectura de divisió d’apertura per la immunització al soroll. Finalment, aquesta tesi estudia les aplicacions del sistema per millorar la detecció en un problema del món real com és veure a través de la boira. La informació de la pol, (Español) La polarización es una de las propiedades de la luz y de la que a menudo se prescinde. Los seres humanos percibimos los rayos de luz y solo procesamos la información proveniente de la intensidad y de las longitudes de onda de la luz. Nuestro sistema óptico carece de la capacidad de "ver" la polarización en comparación con otros animales. La naturaleza vectorial de la polarización está no correlacionada con la información aportada por la intensidad y el color, y esto puede desvelar información adicional para mejorar la tecnología actual. Esta Tesis tiene como objetivo desarrollar una cámara para medir la polarización en una escena 2D. En particular, se centra en el diseño y construcción de un prototipo que mida en el espectro visible el vector de Stokes completo en un solo disparo de manera que el tiempo de adquisición y la ecualización del ruido estén compensados a la vez que se reduzcan los artefactos debidos al movimiento y al registro. La Tesis comienza revisando el actual estado del arte en el campo de imagen polarimétrica. A partir de esto, se realiza el diseño optomecánico de la cámara polarimétrica garantizando una adquisición rápida ya que el diseño implementa unos estados óptimos de polarización para inmunizar el sistema del ruido de gaussiano y de Poisson. Por consiguiente, esta Tesis propone una metodología general de calibración dirigida a la radiometría del sensor, a las aberraciones geométricas de la óptica y a los elementos de polarización en el sistema para transformar las medidas de intensidad en información polarimétrica. Además, esta Tesis estudia dos modos de imagen de la polarización, imagen de Stokes e imagen de la matriz de Mueller, para diferentes aplicaciones. La novedad de este sistema radica en la utilización de estados de polarización óptimos basándose en una arquitectura de división de apertura para la inmunización al ruido. Finalmente, esta Tesis estudia las aplicaciones del sistema para mejorar la detección en un problema del, Postprint (published version)

This paper focuses on the experimental characterization of the polarization behavior of light backscattered through fog. A polarimetric orthogonal state contrast imager and an active, purely polarized white illuminator system are used to evaluate both linear and circular polarization signals. The experiments are carried out in a macro-scale fog chamber under controlled artificial fog conditions. We explore the effect of backscattering in each imaging channel, and the persistence of both polarization signals as a function of meteorological visibility. We confirm the presence of the polarization memory effect with circularly polarized light, and, as a consequence, the maintenance of helicity in backscattering. Moreover, the circular cross-polarized channel is found to be the imaging channel less affected by fog backscattering. These results are useful and should be taken into account when considering active polarimetric imaging techniques for outdoor applications under foggy conditions., This research was funded by the MICINN (project PID2020-119484RB-I00) and by AGAUR Grant 2021FI_B2 00077, supported by the Secretaria d’Universitats i Recerca de la Generalitat de Catalunya (AGAUR) and the Fons Social Europeu (FSE)., Peer Reviewed, Postprint (published version)

In recent times, there has been a surge of interest in LiDAR imaging systems, particularly in outdoor terrestrial applications associated with computer vision. However, a significant hurdle preventing their widespread implementation lies in their limited tolerance for adverse weather conditions, such as fog. To address this challenge, researchers have explored the capability of polarization in improving detection capabilities in such media. This paper explores the potential of LiDAR technology to obtain polarized images through fog and investigates the impact of fog on object detection using digitized temporal signals and point clouds. The study utilizes a LiDAR-polarized imaging system using circular polarization, which has been shown to enhance image contrast in highly-dispersive media. The analysis of the polarimetric information of the backscattered light signal in fog reveals its influence on object detection and evaluates the range difference between orthogonal polarimetric channels: coplanar and cross-configuration. The results demonstrate that cross-configuration detection provides larger range and more detailed point clouds compared to coplanar configuration, particularly benefiting metallic objects, for the same foggy conditions. By utilizing circularly polarized incident light and cross-configuration detection, the LiDAR system can improve the signal-to-noise ratio by filtering out the co-polarized fog responses. However, the range of the system may be reduced compared to nonpolarized detection. Overall, our findings indicate that utilizing a cross-polarization detection setup can effectively reduce the impact of fog backscatter while preserving the return signal from objects of interest in the majority of cases., This work was supported by the Spanish Ministry of Science and Innovation (MICINN) under projects PID2020-119484RB-I00, TED2021-132338B-I00, and PDC2021-121038-I00. The first author gratefully acknowledges the Universitat Politècnica de Catalunya and Banco Santander for the financial support of her predoctoral research grant., Peer Reviewed, Postprint (author's final draft)

Las adaptaciones españolas de la Escala de Deseabilidad Social de Marlowe-Crowne (M-C SDS) han sido baremadas con estudiantes universitarios y adultos evaluados en contextos de selección/promoción laboral. Dada la influencia de la edad y el contexto en la M-C SDS, estos baremos no son apropiados para adultos voluntarios. Se presentan por primera vez datos normativos y de fiabilidad y una versión breve de la adaptación de la M-C SDS de Ávila Espada y Tomé Rodríguez obtenidos con adultos voluntarios españoles (N = 575). Los índices de consistencia interna de la M-C SDS fueron adecuados (alfa = .72-.80). Las diferencias estandarizadas en sus puntuaciones entre adultos voluntarios y estudiantes universitarios o adultos de selección/promoción alcanzaron tamaños del efecto medianos (d = 0.46 y 0.70), lo que justifica la creación de baremos específicos para adultos voluntarios. En dos submuestras independientes de adultos voluntarios, una versión de 18 ítems obtuvo índices de consistencia interna para sus ítems mejores que los de los 33 ítems de la escala completa y que no implicaba una pérdida significativa de fiabilidad (alfa = .72 y .80) ni de validez nomológica. Se ofrecen baremos globales y separados por grupos de edad para las versiones breve y completa de la M-C SDS., The Spanish adaptations of the Marlowe-Crowne Social Desirability Scale (M-C SDS) were normed on samples of university students or of adults assessed in personnel selection/promotion settings. Given the influence of age and assessment setting on the M-C SDS, these norms are inadequate for adult volunteers. This is the first study that provides normative and reliability data and a short form of Ávila Espada and Tomé Rodríguez’s Spanish adaptation of the M-C SDS with Spanish adult volunteers (N = 575). Internal consistency estimates for the M-C SDS were adequate (alphas = .72-.80). The standardized differences in M-C SDS scores between the adult volunteer sample and university student or personnel selection/promotion samples reached values of medium size (d = 0.46 and 0.70). This result supports the development of specific norms for adult volunteers. In two independent subsamples of adult volunteers, a short form of 18-items showed internal consistency indices for its items that were higher than those for the 33 items of the complete scale. This short form did not involve a significant loss of reliability (alphas = .72 and .80) or nomological validity. Global norms and norms for age groups are provided for the short and complete forms of the M-C SDS., Ministerio de Educación y Ciencia, Depto. de Personalidad, Evaluación y Psicología Clínica, Fac. de Psicología, TRUE, pub

Viral protein nanoparticles (ViP NPs) such as virus-like particles and virosomes are structures halfway between viruses and synthetic nanoparticles. The biological nature of ViP NPs endows them with the biocompatibility, biodegradability, and functional properties that many synthetic nanoparticles lack. At the same time, the absence of a viral genome avoids the safety concerns of viruses. Such characteristics of ViP NPs offer a myriad of opportunities for theirapplication at several points across disease development: from prophylaxis to diagnosis and treatment. ViP NPs present remarkable immunostimulant properties, and thus the vaccination field has benefited the most from these platforms capable of overcoming the limitations of both traditional and subunit vaccines. This was reflected in the marketing authorization of several VLP- and virosome-based vaccines. Besides, ViP NPs inherit the ability of viruses to deliver their cargo to target cells. Because of that, ViP NPs are promising candidates as vectors for drug and gene delivery, and for diagnostic applications. In this review, we analyze the pharmaceutical applications of ViP NPs, describing the products that are commercially available or under clinical evaluation, but also the advances that scientists are making toward the implementation of ViP NPs in other areas of major pharmaceutical interest

This article intends to provide all the experimental insights and analyze the best polarimetric calibration method for a division of aperture polarimetric imager considering the different implications it has on the experimental set-up and its performance. Polarimetric cameras require careful calibration for the correct measurement of polarization information. The calibration methods are introduced, intermediate results are presented, and the ability of the set-up to estimate Stokes vectors and Mueller matrices of the samples in passive and active imaging modes is evaluated. Polarization information recovery achieves accuracy errors below the 10% for all polarization modes when the Data Reduction Matrix or the Eigenvalue Calibration Method are used. Such performance, however, degrades significantly when using the Polarizer Calibration Method. To the best of our knowledge, this is the first time such a detailed comparison of calibration methods is presented in the literature, and it is also the first time the Polarizer Calibration Method is applied to a division of aperture polarimeter., Ministerio de Ciencia e Innovación (PDC2021-121038-I00, PID2020-119484RB-I00); Agència de Gestió d’Ajuts Universitaris i de Recerca (2020FI_B2 00068); European Social Fund; Universitat Politècnica de Catalunya; Banco Santander., Peer Reviewed, Postprint (published version)