Assessment of colour simulation tools and study of colour preference in red-green dichromats

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Psicología, Departamento de Personalidad, Evaluación y Tratamiento Psicológico II (Psicología Diferencial y del Trabajo), leída el 15-12-2015.Los observadores con visión normal del color (tricrómatas normales) poseen tres tipos de conos retinianos, que responden máximamente a las longitudes de onda larga (conos L), media (M) y corta (S). Los dicromatismos rojo-verde son alteraciones genéticas de la visión del color en las que, aparte del fotopigmento presente en los conos S, únicamente existe otro tipo de fotopigmento, el que contienen los conos L (deuteranopia) o M (protanopia). Afectan a un 2% de los varones y conllevan una discriminación del color reducida y una sensibilidad espectral diferente de la del tricromatismo normal. Los dos estudios empíricos que componen esta tesis se ocupan de la adecuación de las herramientas que simulan los dicromatismos rojoverde y de las preferencias del color de quienes los padecen. El primer estudio propone un método, Simulcheck, diseñado para evaluar la precisión de las herramientas de simulación del color y su objetivo principal es comprobar la adecuación de Simulcheck como método de evaluación. Para conseguir este objetivo, se comparó el comportamiento de dicrómatas reales con el de dicrómatas simulados mediante tres herramientas diferentes. El grado de similitud entre el comportamiento de ambos tipos de observadores se utilizó como criterio para evaluar la precisión de las herramientas. Un grupo de 10 daltónicos dicrómatas (5 protanopes; 5 deuteranopes) y un grupo de 10 tricrómatas normales realizaron dos tareas: (1) identificación de estímulos pseudoacromáticos para determinar los dos ángulos cromáticos (valores huv) que generaban una respuesta mínima en el mecanismo amarillo-azul y, consecuentemente, la percepción de estímulos pseudoacromáticos; (2) mínimo contraste acromático para determinar el fondo acromático que producía un contraste mínimo (cambio más próximo a cero en el mecanismo acromático) para cada estímulo pseudoacromático seleccionado en la tarea anterior (valores LR). Se utilizaron dos conjuntos estimulares, ambos con 40 estímulos, que cubrían todo el círculo cromático mediante intervalos de 9° en huv: en el de croma máximo, los estímulos presentaban la máxima saturación posible del monitor en cada ángulo; en el de croma constante, los estímulos presentaban valores similares en croma y claridad (C*uv y L*), definidos por el ángulo de tono menos saturado disponible en la gama del monitor...Common observers (normal trichromats) have three types of cones in the retina. These cones respond maximally to long (L cones), medium (M) and short (S) wavelengths. Red-green dichromatisms are genetic alterations of colour vision which results in only two photopigments: one photopigment in the S cones and another photopigment either in the L cones (deuteranopia) or in the M cones (protanopia). They affect 2% of males and result in reduced colour discrimination and different spectral sensitivity in comparison to normal trichromatism. The two empirical studies of this thesis dissertation deal with the suitability of colour simulation tools that mimic the red-green dichromatisms and the colour preferences of red-green dichromats. The first study devises a method, Simulcheck, designed to assess the accuracy of colour simulation tools. The main goal of this study is to check the suitability of Simulcheck as an assessment method for these tools. In order to do this, the behaviour of real dichromats and the behaviour of simulated dichromats are compared through three different tools. The similarity degree between both kinds of observers is used as the criterion to assess the accuracy of the assessed tools. A group of 10 red-green dichromats (5 protanopes; 5 deuteranopes) and a group of 10 normal trichromats performed two tasks: (1) the Pseudoachromatic Stimuli Identification task to determine the two chromatic angles (huv values) that generate a minimum response in the yellow-blue mechanism and, consequently, the perception of pseudoachromatic stimuli; (2) the Minimum Achromatic Contrast task to determine the achromatic background that produced a minimum contrast (change near zero in the achromatic mechanism) for each pseudoachromatic stimulus selected in the previous task (LR values). Two 40 stimulus sets were used, covering the full chromatic circle by intervals of 9° in huv: in the maximum chroma set, the stimuli were presented at the maximum possible saturation for the screen in each angle; in the constant chroma set, the stimuli were presented with similar values of chroma and lightness (C*uv and L*), as defined by the less saturated angle available in the screen gamut...Depto. de Psicología Social, del Trabajo y DiferencialFac. de PsicologíaTRUEunpu

Colorimetry and Dichromatic Vision

Normal trichromats have three types of cone photoreceptors: L, M, and S cones (most sensitive to long, medium, or short wavelengths, respectively). Therefore, standard colorimetry is based on three variables (X, Y, Z). Dichromats only have two types of functional cones due to genetic factors. The main consequences are that dichromats (1) confuse colors that can only be discriminated by the response of the type of cone they lack and (2) make errors when naming colors. Chromaticity diagrams can be used to specify dichromats’ color confusions. Confusion points represent imaginary stimuli that only activate L, M, or S cones. Confusion lines radiate from confusion points and represent pseudoisochromatic stimuli (i.e., colors confused by the corresponding type of dichromat if presented at an appropriate intensity). Dichromat’s color appearance models have been developed to simulate the colors supposedly seen by dichromats, and there exist color simulation tools that implement some of those models

Urban and economic activities in metropolitan structuring axes. The contribution of Google Places geolocated data

Los ejes viarios metropolitanos son espacios de centralidad urbana y de oportunidad para promover una mejor conectividad entre las distintas partes del continuo urbano. En este sentido, la caracterización funcional de seis ejes representativos en Madrid, Barcelona, París, Londres, Nueva York y Ciudad de México permite obtener un diagnóstico actual sobre la densidad y diversidad de actividades económicas y urbanas, con el fin identificar aspectos clave sobre los que incidir para mejorar su estructura funcional y social. Para ello, se propone un método que adopta los datos geolocalizados de la red social Google Places como principal fuente de información. De la investigación se deducen importantes similitudes en el carácter funcional de los ejes, entre otras, la predominancia de las actividades relacionadas con los servicios y el comercio o la mayor diversidad de actividades económicas y urbanas en los espacios más centrales. Pero también se identifican diferencias, como son la especialización de determinadas actividades características en cada eje metropolitano o la diferencial relación entre la densidad de población y cantidad de actividades, tanto en términos de densidad como en cuantificación lineal. En definitiva, el método propuesto abre nuevas posibilidades para la planificación estratégica de actividades económicas y urbanas en ámbitos metropolitanos.Metropolitan road axes are spaces of urban centrality and opportunity to promote a greater connectivity between different parts of the urban continuum. In this sense, the functional characterization of six representative axes in Madrid, Barcelona, Paris, London, New York and Mexico City allows obtaining a current analysis of the density and diversity of economic and urban activities to identify key aspects over which to influence to improve their functional and social structure. For this, a method is proposed that adopts the geolocation data from Google Places social network as a main source of information. From the research, important similarities in the functional character of the axes are deduced, among other the predominance of activities related to services and shopping or the greater diversity of economic and urban activities in more central spaces. But differences are also identified, such as the specialization of certain activities characteristic in each metropolitan axis or the differential relationship between population density and the number of activities both in terms of density and linear quantification. All in all, the method proposed opens new possibilities for the strategic planning of economic and urban activities in metropolitan areas.Esta investigación ha recibido financiación de la Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital de la Generalitat Valenciana y el Fondo Social Europeo (ACIF/2020/173)

Reading Urban Transformation Based on Geolocated Crowdsourced Data

Social and economic instability in cities caused by the pandemic emergency has highlighted the necessity of carrying out diagnoses to identify courses of action for the purpose of reducing the vulnerability of urban areas in the face of future crisis. This research aims to identify how the impact of the COVID-19 pandemic and the measures adopted have influenced urban and economic activities and the use, presence and preferences of urban public spaces. Specifically, an analysis in several cities before and after the most critical phases of the pandemic is proposed based on virtual social network geodata. Since each individual represents a node of information exchange, it is hypothesized that a comparison between the data generated before and after the pandemic offer a first glance at how changes in the social (collective behaviors and preferences) and physical (economic and urban activities) dimensions in urban environments have been produced. The results provide a descriptive and contrasted analysis that evidences the relevance of using crowdsourced data for monitoring the changes and transformations that took place as a result of the pandemic crisis in order to inform decision-making for future urban policies and actions

Certificación de competencias laborales en las pymes de la zona de Concepción, Chile (2004).

Mediante encuestas estructuradas y entrevistas realizadas a pequeñas y medianas empresas del Gran Concepción (Chiguayante, Concepción, Talcahuano, San Pedro de la Paz), se obtiene información cuantitativa y cualitativa sobre el grado de conocimiento que tiene el empresario Pyme referente al tema de las Competencias Laborales y su certificación.En general, la Pyme no tiene muy claro qué es competencia laboral, y menos aún en qué consiste su certificación, sin embargo, está conciente que tarde o temprano la certificación de competencias de sus trabajadores será un gran valor para la empresa y un requisito para entrar a nuevos mercados y mantenerse en ellos. Actualmente la brecha que separa a la Pyme de la Certificación de Competencias Laborales se debe primeramente a información y divulgación de ésta, donde destaca los beneficios que se obtendrán por medio de la Certificación, tanto para la empresa como para el trabajador.Es importante destacar que este estudio se realizó con el apoyo de la Cámara de producción y del Comercio de Concepción

Robust colour constancy in red-green dichromats

Colour discrimination has been widely studied in red-green (R-G) dichromats but the extent to which their colour constancy is affected remains unclear. This work estimated the extent of colour constancy for four normal trichromatic observers and seven R-G dichromats when viewing natural scenes under simulated daylight illuminants. Hyperspectral imaging data from natural scenes were used to generate the stimuli on a calibrated CRT display. In experiment 1, observers viewed a reference scene illuminated by daylight with a correlated colour temperature (CCT) of 6700K; observers then viewed sequentially two versions of the same scene, one illuminated by either a higher or lower CCT (condition 1, pure CCT change with constant luminance) or a higher or lower average luminance (condition 2, pure luminance change with a constant CCT). The observers' task was to identify the version of the scene that looked different from the reference scene. Thresholds for detecting a pure CCT change or a pure luminance change were estimated, and it was found that those for R-G dichromats were marginally higher than for normal trichromats regarding CCT. In experiment 2, observers viewed sequentially a reference scene and a comparison scene with a CCT change or a luminance change above threshold for each observer. The observers' task was to identify whether or not the change was an intensity change. No significant differences were found between the responses of normal trichromats and dichromats. These data suggest robust colour constancy mechanisms along daylight locus in R-G dichromacy.This work was supported by FEDER through the COMPETE Program and by the Portuguese Foundation for Science and Technology (FCT) in the framework of the project PTDC/MHC-PCN/4731/2012 and by Ministerio de Ciencia y Competitividad in the framework of the project PSI2012-37778. LA was supported by Beca Santander JPI2014. The publication of this article was funded by the Anglia Ruskin Open Access Fund.info:eu-repo/semantics/publishedVersio

Chabazite and dolomite formation in a dolocrete profile an example of complex alkaline paragenesis in Lanzarote, Canary Islands

This paper studies the weathering and soil formation processes operating on detrital sediments containing alkaline volcanic rock fragments of the Mirador del Río dolocrete profile. The profile consists of a lower horizon of removilised weathered basalts, an intermediate red sandy mudstones horizon with irregular carbonate layers and a topmost horizon of amalgamated carbonate layers with root traces. Formation occurred in arid to semiarid climates, giving place to a complex mineralogical association, including Mg-carbonates and chabazite, rarely described in cal/dolocretes profiles. Initial vadose weathering processes occurred in the basalts and in directly overlying detrital sediments, producing (Stage 1) red-smectites and dolomicrite. Dominant phreatic (Stage 2) conditions allowed precipitation of coarse-zoned dolomite and chabazite filling porosities. In Stages 3 and 4, mostly pedogenic, biogenic processes played an important role in dolomite and calcite accumulation in the profile. Overall evolution of the profile and its mineralogical association involved initial processes dominated by alteration of host rock, to provide silica and Mg-rich alkaline waters, suitable for chabazite and dolomite formation, without a previous carbonate phase. Dolomite formed both abiogenically and biogenically, but without a previous carbonate precursor and in the absence of evaporites. Dominance of calcite towards the profile top is the result of Mg/Ca decrease in the interstitial meteoric waters due to decreased supply of Mg from weathering, and increased supply of Ca in aeolian dust. Meteoric origin of the water is confirmed by C and O isotope values, which also indicate lack of deep sourced CO2. The dolocrete studied and its complex mineral association reveal the complex interactions that occur at surface during weathering and pedogenesis of basalt-sourced rocks

La diabetes mellitus. Herramienta para la toma de decisiones compartidas en la diabetes mellitus tipo II

La Diabetes es una enfermedad crónica y prevalente, que tiene un desarrollo gradual ypara cuyo control son esenciales el consejo y la guía del personal sanitario, junto conla atención del paciente. Por lo tanto, resulta imprescindible que el paciente conozcay entienda su patología junto con las opciones para su tratamiento, cómo afecta a sucalidad de vida, así como que pueda valorar sus propias preferencias y sepa dónde hade buscar información. Se ha elaborado una herramienta de ayuda con el objetivo deproporcionar información sobre las diferentes opciones de tratamiento, de manera quefacilite la reflexión y la discusión conjunta con el profesional. El resultado ha sido la creaciónde un tríptico. En conclusión, se ha conseguido implementar un instrumento deayuda para que los pacientes conozcan más detalladamente acerca de su patología ypuedan tomar decisiones compartidas con el profesional sanitario según sus preferencias,aumentando la confianza en el sistema de salud y la adherencia al tratamiento.Diabetes is a chronic and prevalent disease, which has a gradual development andfor its control are essential advice and guidance of health personal, together with thepatient’s attention. Therefore, it is imperative that the patient knows and understands their pathology along with the options for their treatment, how it affects their quality oflife, as well as being able to value their own preferences and look for where to look forinformation. An aid tool has been developed with the objective of providing informationon the different treatment options, so as to facilitate reflection and joint discussion withthe professional. The result has been the creation of a triptych. In conclusion, an instrumenthas been implemented to help patients to know more about their pathology andto make decisions that are shared with the healthcare professional according to theirpreferences, increasing confidence in the health system and adherence to treatment

Experience with the use of Rituximab for the treatment of rheumatoid arthritis in a tertiary Hospital in Spain: RITAR study

There is evidence supporting that there are no relevant clinical differences between dosing rituximab 1000 mg or 2000 mg per cycle in rheumatoid arthritis (RA) patients in clinical trials, and low-dose cycles seem to have a better safety profile. Our objective was to describe the pattern of use of rituximab in real-life practice conditions. Methods: Rituximab for RA in clinical practice (RITAR) study is a retrospective cohort study from 2005 to 2015. Eligibility criteria were RA adults treated with rituximab for active articular disease. Response duration was the main outcome defined as months elapsed from the date of rituximab first infusion to the date of flare. A multivariable analysis was performed to determine the variables associated with response duration. Results: A total of 114 patients and 409 cycles were described, 93.0% seropositive and 80.7% women. Rituximab was mainly used as second-line biological therapy. On demand retreatment was used in 94.6% of cases versus fixed 6 months retreatment in 5.4%. Median response duration to on demand rituximab cycles was 10 months (interquartile range, 7–13). Multivariable analysis showed that age older than 65 years, number of rituximab cycles, seropositivity, and first- or second-line therapy were associated with longer response duration. The dose administered at each cycle was not significantly associated with response duration. Conclusions: Our experience suggests that 1000 mg rituximab single infusion on demand is a reasonable schedule for long-term treatment of those patients with good response after the first cycles, especially in seropositive patients and when it is applied as a first- or second-line biological therap