Validación clínica de algoritmos de procesado en imagen médica. Aplicación en resonancia magnética multiparamétrica de próstata

[ES] Hoy en día, el cáncer de próstata es considerado uno de los carcinomas malignos más prevalentes entre la población masculina, siendo en España, el segundo más frecuente y el tercero en mortalidad. El tratamiento consta principalmente de procedimientos quirúrgicos, lo que puede producir en el paciente, efectos secundarios y secuelas. Por ello, surge la necesidad del diagnóstico precoz, de establecer el riesgo de progresión de los tumores y valorar a cada paciente antes de tomar cualquier decisión terapéutica. Con el propósito de obtener una mayor cantidad de información sobre la patología, una de las técnicas más utilizadas, es la Imagen por Resonancia Magnética (RM), con la cual, de manera no invasiva, se puede clasificar de forma local y regional los estados en pacientes con cáncer. Los avances en la tecnología han derivado en el desarrollo de RM multiparamétrica, en el que se combina secuencias T2W anatómicas con evaluaciones funcionales y fisiológicas, incluyendo imágenes de difusión e imágenes de perfusión. Al existir una excesiva variación en la interpretación de las imágenes de cáncer de próstata, para estandarizar el proceso de evaluación RM multiparamétrica y su aplicación, se creó el Sistema de Información y Datos en Imagen de Próstata (PI-RADS), formado por directrices básicas para la adquisición de las imágenes y la evaluación de cada lesión analizando la información proveniente de las distintas secuencias. El presente trabajo consiste en la validación de los algoritmos de preprocesado involucrados en el análisis de las distintas secuencias, siendo estos: selección de la función de entrada arterial en imágenes de perfusión DCE y registros intersecuencia. Se lleva a cabo un proceso de validación completo e independiente para cada algoritmo de preprocesado, obteniéndose métricas y medidas estadísticas para evaluar el buen funcionamiento de los distintos algoritmos en una base de datos de pacientes representativos de la práctica clínica.[EN] One of the most prevalent malignant carcinomas among the male population in these days is prostate cancer, also it is the second most frequent in Spain and the third in mortality. The treatment consists mainly of surgical procedures, which can produce side effects and sequels. Therefore, the need for early diagnosis arises, to establish the risk of tumor progression and to evaluate each patient before taking any therapeutic decision. In order to obtain a greater amount of information about this pathology, one of the most used techniques is Magnetic Resonance Imaging (MRI), which with the use of contrast agents, states in cancer patients can be locally and regionally classified. Advances in technology have led to the development of Multiparametric MRI (mpMRI), which combines anatomical T2W sequences with functional and physiological assessments, including diffusion and perfusion imaging. As there is excessive variation in the interpretation of prostate cancer images, in order to standardize the mpMRI evaluation process and its application, the Prostate Image-Reporting and Data System (PI-RADS) was created, consisting of basic guidelines for the evaluation of each lesion with this type of analysis. The present work is about the validation of a series of pre-processing algorithms for the evaluation of prostate cancer using mpMRI and the recommendations of PI-RADS. These algorithms are the selection of the arterial input function in DCE perfusion images and the registration of images. A complete and independent validation process is carried out for each type of analysis, obtaining metrics and statistical measures that allow differentiating and demonstrating the validity of the application under study.[CA] Hui en dia, el càncer de pròstata és considerat un dels carcinomes malignes més prevalents entre la població masculina, sent a Espanya, el segon més freqüent i el tercer en mortalitat. El tractament consta principalment de procediments quirúrgics, la qual cosa pot produir en el pacient, efectes secundaris i seqüeles. Per això, sorgix la necessitat del diagnòstic precoç, d'establir el risc de progressió dels tumors i valorar cada pacient abans de prendre qualsevol decisió terapèutica. Amb el propòsit d'obtindre una major quantitat d'informació sobre la patologia, una de les tècniques més utilitzades, és la Imatge per Ressonància Magnètica (RM) , amb la qual, de manera no invasiva, es pot classificar de forma local i regional els estats en pacients amb càncer. Els avanços en la tecnologia han derivat en el desenrotllament de RM multiparamétrica, en el que es combina seqüències T2W anatòmiques amb avaluacions funcionals i fisiològiques, incloent imatges de difusió i imatges de perfusió. A l'existir una excessiva variació en la interpretació de les imatges de càncer de pròstata, per a estandarditzar el procés d'avaluació RM multiparamétrica i la seua aplicació, es va crear el Sistema d'Informació i Dades en Imatge de Pròstata (PI- RADS) , format per directrius bàsiques per a l'adquisició de les imatges i l'avaluació de cada lesió analitzant la informació provinent de les distintes seqüències. El present treball consistix en la validació dels algoritmes de preprocessat involucrats en l'anàlisi de les distintes seqüències, sent estos: selecció de la funció d'entrada arterial en imatges de perfusió DCE i registres interseqüència. Es du a terme un procés de validació complet i independent per a cada algoritme de preprocessat, obtenint-se mètriques i mesures estadístiques per a avaluar el bon funcionament dels distints algoritmes en una base de dades de pacients representatius de la pràctica clínica.Mancebo González, M. (2020). Validación clínica de algoritmos de procesado en imagen médica. Aplicación en resonancia magnética multiparamétrica de próstata. Universitat Politècnica de València. http://hdl.handle.net/10251/162077TFG

Análisis de texturas de imágenes PET/TC para la caracterización, cuantificación y ayuda en el diagnóstico del cáncer de mama

[ES] Una de las características más comunes que presentan los tumores cancerígenos es la falta de oxígeno o hipoxia, la cual contribuye de manera directa a su proliferación y metástasis, además de disminuir su sensibilidad a tratamientos comunes, tales como la radioterapia. A partir de la evaluación y del desarrollo de la hipoxia en el microentorno del tumor se podrían obtener parámetros de medida de interés para la caracterización y planificación de terapias personalizadas contra el cáncer. El principal radiofármaco utilizado en imagen para la evaluación y cuantificación de la hipoxia es el 18F-misonidazol. Esta sustancia radiactiva se une a moléculas grandes de las células cancerosas con una concentración baja de oxígeno, de forma que, la radiación que emite se puede detectar mediante tomografía por emisión de positrones (PET). Con el objetivo de obtener una mayor cantidad de información, en este estudio se van a utilizar imágenes corregistradas PET/TC, las cuales proporcionan diagnósticos más exactos al disponer de información más precisa. Para la caracterización de la lesión, en este estudio centrado en cáncer de mama, se va a utilizar un biomarcador de análisis de texturas, específicamente diseñado para medir la agresividad tumoral que ofrece información cuantitativa de aspectos subjetivos, principalmente la heterogeneidad de las imágenes, debida por ejemplo a una elevada proliferación vascular, necrosis, etc. Considerándose este aspecto esencial en los tumores, sobre todo en los más agresivos, el uso de esta aplicación es fundamental, ya que con una correcta medida de la heterogeneidad se puede ayudar a la caracterización de estos tumores y a la determinación del pronósticos de los pacientes. Este trabajo ha sido propuesto y realizado en la empresa Quibim, la cual ha proporcionado las interfaces gráficas necesarias para la visualización y segmentación de las imágenes PET/TC y el biomarcador de análisis de texturas utilizado en el postprocesado sobre MatLab. Las imágenes corregistradas han sido facilitadas por el Centro Nacional de Investigaciones Oncológicas (CNIO), que, en colaboración con Quibim, tiene el objetivo de valorar el uso del radiofármaco misonidazol en predicción, diagnóstico y tratamiento en pacientes con cáncer de mama.[EN] One of the most common features of cancerous tumour is oxygen deficiency or hypoxia, which directly affects their proliferation and metastases and, moreover, decreases their sensitivity to the effects of medical treatments, such as radiation therapy. Based on the evaluation and development of hypoxia in the microenvironment of the tumour, measurement parameters could be obtained for the characterization and planning of personalized therapies against cancer. The main radiopharmaceutical used in imaging for the evaluation and quantification of hypoxia is 18F-Misonidazole. This radioactive drug binds to big molecules in cancer cells with oxygen deficiency, so, the radiation it emits can be detected by Positron Emission Tomography (PET). In order to obtain a greater amount of information, corregistered PET/CT will be used in this study, which provide more exact diagnostics when more accurate information is available. A texture analysis biomarker has been used to characterize the lesion in breast cancer, which has been designed to measure tumour aggressiveness that provides quantitative information on subjective aspects, mainly the heterogeneity in the images, due to, for example, high vascular proliferation, necrosis, etc. Considering this essential aspect in tumours, especially in the most aggressive ones, the use of this application is fundamental, because a correct measurement of heterogeneity can help in characterizing these tumours and in determining the prognosis of patients. This paper has been proposed and carried out in the Quibim company, which has provided the necessary graphical interfaces for the visualization and segmentation of PET/CT images and, the texture analysis biomarker used in the postprocessing on MatLab. The corregistered images have been provided by the National Center for Oncology Research (CNIO), which, in collaboration with Quibim, aims for the evaluation of the use of misonidazole in prediction, diagnosis and treatment in breast cancer patients.Mancebo González, M. (2019). Análisis de texturas de imágenes PET/TC para la caracterización, cuantificación y ayuda en el diagnóstico del cáncer de mama. http://hdl.handle.net/10251/127655TFG

The Documentary Representation of a Lost Material Reality: The Building of Monasteries in the City of León (c. 1000-1050)

Between 1050 and 1300 a transformation occurred in the mediaeval west, characterized by the proliferation of representative structures in stone. The case of León is unusual because it preserves few remains from this timeframe, but numerous documented mentions of buildings. Through the foundation testimonies of several monasteries at the beginning of the 11th century, the intention is to recognize whether the phenomenon of petrification of wealth had early beginnings in the city. For this purpose, a review of who the founders were, the resources they had, the materiality of the buildings and the motivations they satisfied has been carried out.Entre 1050 y 1300 se produjo una transformación en el occidente medieval caracterizada por la proliferación de construcciones representativas en piedra. El caso de León es particular porque conserva pocos restos materiales de esta cronología, pero numerosas menciones documentales a edificios. A través de los testimonios de fundación de varios monasterios de comienzos del siglo XI se pretende reconocer si el fenómeno de la petrificación de la riqueza tuvo un inicio temprano en la ciudad. Para esto se ha hecho una revisión de quiénes fueron los fundadores, con qué recursos contaron, cuál fue la materialidad de los edificios y a qué motivaciones respondieron

Acoustic characterization and perceptual analysis of the relative importance of prosody in speech of people with Down syndrome

There are many studies that identify important deficits in the voice production of people with Down syndrome. These deficits affect not only the spectral domain, but also the intonation, accent, rhythm and speech rate. The main aim of this work is the identication of the acoustic features that characterize the speech of people with Down syndrome, taking into account the different frequency, energy, temporal and spectral domains. The comparison of the relative weight of these features for the characterization of Down syndrome people's speech is another aim of this study. The openSmile toolkit with the GeMAPS feature set was used to extract acoustic features from a speech corpus of utterances from typically developing individuals and individuals with Down syndrome. Then, the most discriminant features were identied using statistical tests. Moreover, three binary classiers were trained using these features. The best classication rate, using only spectral features, is 87.33%, and using frequency, energy and temporal features, it is 91.83%. Finally, a perception test has been performed using recordings created with a prosody transfer algorithm: the prosody of utterances from one group of speakers was transferred to utterances of another group. The results of this test show the importance of intonation and rhythm in the identication of a voice as non typical. As conclusion, the results obtained point to the training of prosody in order to improve the quality of the speech production of those with Down syndrome

Uniform, luminescent Eu:LuF3 nanoparticles

A simple procedure for the synthesis of orthorhombic, uniform, LuF3 particles with two different morphologies (rhombus- and cocoon-like) and nanometer and sub-micrometer size, respectively, is reported. The method consists in the aging, at 120 °C for 2 h, a solution containing [BMIM]BF4 ionic liquid (0.5 mL) and lutetium acetate (in the case of the rhombi) or lutetium nitrate (in the case of the cocoons) (0.02 M) in ethylene glycol (total volume 10 mL). This synthesis method was also adequate for the synthesis of Eu3+-doped LuF3 particles of both morphologies, whose luminescence properties were investigated in detail. The experimental observations reported herein suggest that these materials are suitable phosphors for optoelectronic as well as in vitro biotechnological applications.MEC MAT2012-34919Junta de Andalucía JA FQM 06090CSIC 201460E00

Weakly-nonlinear analysis of the Rayleigh–Taylor instability in a vertically vibrated, large aspect ratio container

We consider a horizontal liquid layer supported by air in a wide (as compared to depth) container, which is vertically vibrated with an appropriately large frequency, intending to counterbalance the Rayleigh-Taylor instability of the fíat, rigid-body vibrating state. We apply a long-wave, weakly-nonlinear analysis that yields a generalized Cahn-Hilliard equation for the evolution of the fluid interface, with appropriate boundary conditions obtained by a boundary layer analysis. This equation shows that the stabilizing effect of vibration is like that of surface tensión, and is used to analyze the linear stability of the fíat state, and the local bifurcation at the instability threshold

Prosodic feature analysis for automatic speech assessment and individual report generation in people with Down syndrome

Producción CientíficaEvaluating prosodic quality poses unique challenges due to the intricate nature of prosody, which encompasses multiple form–function profiles. These challenges are more pronounced when analyzing the voices of individuals with Down syndrome (DS) due to increased variability. This paper introduces a procedure for selecting informative prosodic features based on both the disparity between human-rated DS productions and their divergence from the productions of typical users, utilizing a corpus constructed through a video game. Individual reports of five speakers with DS are created by comparing the selected features of each user with recordings of individuals without intellectual disabilities. The acquired features primarily relate to the temporal domain, reducing dependence on pitch detection algorithms, which encounter difficulties when dealing with pathological voices compared to typical ones. These individual reports can be instrumental in identifying specific issues for each speaker, assisting therapists in defining tailored training sessions based on the speaker’s profile.Ministerio de Ciencia e Innovación/Agencia Estatal de Investigación (AEI)/10.13039/501100011033 y Fondo Europeo de Desarrollo Regional (FEDER) - (Project PID2021-126315OB-I00

Using challenges to enhance a learning game for pronunciation training of English as a second language

Producción CientíficaLearning games have a remarkable potential for education. They provide an emergent form of social participation that deserves the assessment of their usefulness and efficiency in learning processes. This study describes a novel learning game for foreign pronunciation training in which players can challenge each other. Native Spanish speakers performed several pronunciation activities during a one-month competition using a mobile application, designed under a minimal pairs approach, to improve their pronunciation of English as a foreign language. This game took place in a competitive scenario in which students had to challenge other participants in order to get high scores and climb up a leaderboard. Results show intense practice supported by a significant number of activities and playing regularity, so the most active and motivated players in the competition achieved significant pronunciation improvement results. The integration of automatic speech recognition (ASR) and text-to-speech (TTS) technology allowed users to improve their pronunciation while being immersed in a highly motivational game.Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional (grant TIN2014-59852-R)Junta de Castilla y Leon (grant VA050G18

The taxonomic status and the geographical relationships of the Macaronesian endemic moss Fissidens luisieri (Fissidentaceae) based on DNA sequence data

Copyright © 2009 by The American Bryological and Lichenological Society, Inc.The taxonomic identity and the geographical relationships of the Macaronesian endemic moss Fissidens luisieri have been studied using the chloroplast trnGUCC intron, the spacer between trnM and trnV, together with the trnV intron and ITS1 and ITS2 sequences. A comparison of F. luisieri with the most closely related species, F. serrulatus, from the same geographical areas reveals that the distribution pattern of F. serrulatus and F. luisieri, rather than their morphological differences, explains the observed differences. Therefore, we conclude that both names correspond to the same species. One of the primers for the chloroplast trnGUCC intron and both primers for the trnM–trnV region were designed for this study; they can all be widely used within bryophytes because they provide similar degrees of variability as other regions of the chloroplast genome such as the atpB–rbcL intergenic spacer

Distribution patterns of Leucodon species in Macaronesia, with special reference to the Canary Islands

Copyright © 2009 Adac. Tous droits réservés.The genus Leucodon is represented in Macaronesia by three species, L. sciuroides, L. canariensis and L. treleasei, the latter two being endemic to this region. An analysis of distribution, frequency and habitats for all three species in this region shows singular patterns for each species, mainly related to habitat conservation and type of habitat. Leucodon canariensis is the most restricted species as regards habitat conditions, with a confirmed presence only on Madeira and the Canary Islands, although more abundant in the latter. Leucodon treleasei exhibits the widest habitat amplitude, especially on Madeira, and it is present in all three northern archipelagos. Leucodon sciuroides is the most tolerant species to aridity and is mainly found on Madeira and the Canary Islands, although its occurrence was confirmed in all the Macaronesian archipelagos