Diseño e implementación de un módulo para la anotación de imágenes médicas

Se comenzó el trabajo recabando información sobre los distintos enfoques que se le había dado a la anotación a lo largo del tiempo, desde anotación de imágenes a mano, pasando por anotación de imágenes utilizando características de bajo nivel, como color y textura, hasta la anotación automática. Tras entrar en materia, se procedió a estudiar artículos relativos a los diferentes algoritmos utilizados para la anotación automática de imágenes. Dado que la anotación automática es un campo bastante abierto, hay un gran numero de enfoques. Teniendo las características de las imágenes en particular en las que se iba a centrar el proyecto, se fueron descartando los poco idoneos, bien por un coste computacional elevado, o porque estaba centrado en un tipo diferente de imágenes, entre otras cosas. Finalmente, se encontró un algoritmo basado en formas (Active Shape Model) que se consideró que podría funcionar adecuadamente. Básicamente, los diferentes objetos de la imagen son identicados a partir de un contorno base generado a partir de imágenes de muestra, siendo modicado automáticamente para cubrir la zona deseada. Dado que las imágenes usadas son todas muy similares en composición, se cree que puede funcionar bien. Se partió de una implementación del algoritmo programada en MATLAB. Para empezar, se obtuvieron una serie de radiografías del tórax ya anotadas. Las imágenes contenían datos de contorno para ambos pulmones, las dos clavículas y el corazón. El primer paso fue la creación de una serie de scripts en MATLAB que permitieran: - Leer y transformar las imágenes recibidas en RAW, para adaptarlas al tamaño y la posición de los contornos anotados - Leer los archivos de texto con los datos de los puntos del contorno y transformarlos en variables de MATLAB - Unir la imagen transformada con los puntos y guardarla en un formato que la implementación del algoritmo entendiera. Tras conseguir los ficheros necesarios, se procedió a crear un modelo para cada órgano utilizando para el entrenamiento una pequeña parte de las imágenes. El modelo obtenido se probó con varias imágenes de las restantes. Sin embargo, se encontro bastante variación dependiendo de la imagen utilizada y el órgano detectado. ---ABSTRACT---The project was started by procuring information about the diferent approaches to image annotation over time, from manual image anotation to automatic annotation. The next step was to study several articles about the diferent algorithms used for automatic image annotation. Given that automatic annotation is an open field, there is a great number of approaches. Taking into account the features of the images that would be used, the less suitable algorithms were rejected. Eventually, a shape-based algorithm (Active Shape Model) was found. Basically, the diferent objects in the image are identified from a base contour, which is generated from training images. Then this contour is automatically modified to cover the desired area. Given that all the images that would be used are similar in object placement, the algorithm would probably work nicely. The work started from a MATLAB implementation of the algorithm. To begin with, a set of chest radiographs already annotated were obtained. These images came with contour data for both lungs, both clavicles and the heart. The first step was the creation of a series of MATLAB scripts to join the RAW images with the annotation data and transform them into a format that the algorithm could read. After obtaining the necessary files, a model for each organ was created using part of the images for training. The trained model was tested on several of the reimaining images. However, there was much variation in the results from one image to another. Generally, lungs were detected pretty accurately, whereas clavicles and the heart gave more problems. To improve the method, a new model was trained using half of the available images. With this model, a significant inprovement of the results can be seen

Diseño y preparación de un prototipo de detector de infrarrojos para cromatografía HPLC

Este proyecto tiene como objetivo diseñar un elemento que permita conectar un detector de infrarrojos a un aparato cromatográfico en uso actualmente en el laboratorio de la universidad. Para ello se estudiarán los conceptos involucrados en los procesos de cromatografía, incluyendo sus funciones, los detectores que se usan en la experimentación actual, centrándose principalmente en el IR, y los materiales utilizados en estas prácticas. Posteriormente, se escogerán ciertos elementos para formar finalmente una celda de IR capaz de acoplarse al sistema completo. Una vez obtenido un montaje que cumpla con los objetivos propuestos, se procederá a probar el resultado con unos procesos de experimentación sobre muestras conocidas, para determinar si la sensibilidad y resolución del montaje son suficientes para aplicarlos en análisis habitualmente. Los resultados obtenidos determinarán la viabilidad de este método en diferentes situaciones, ya que el objetivo de la experimentación es tener diferentes enfoques, por ejemplo, se probará con polímeros de alto peso, de bajo peso, mezclas de polímeros o un copolímero. La utilización complementaria de diversos equipos de detección y medición permite estudiar los análisis desde diferentes puntos de vista, sin embargo, suponen una complicación en el montaje. Se comprueba que si el espacio de paso por la celda tiene una anchura de menos de 2 mm, el funcionamiento es más adecuado para aplicar la espectrografía. Se ha hecho un prototipo funcional, que ha permitido realizar una experimentación que, debido al uso de cloroformo como disolvente, otorga resultados interesantes en las bandas de IR entre 1600 y 2200 cm-1, esta región es adecuada para el estudio de los polímeros que se analizan, como el ácido poliláctico o el PMMA. Además estas señales obtenidas presentan la suficiente intensidad como para realizar un cromatograma HPLC-GPC

DYNAMIC SEISMIC RESPONSE OF LA MISSION BRIDGE IN BAJA CALIFORNIA, MÉXICO

The analytical and experimental seismic response of La Mission Bridge, and the site sub-surface characterization on its neighborhood is presented in this paper. SAP 2000 (Structural Analysis Program) was used to model and characterize numerically the expected response of the bridge in terms of their vibration natural frequencies and maximum displacement. It was also generated the scenario of the bridge response upon strong motion. In both cases, ambient vibration measurements were used for the experimental studies. The stiffness matrix method was used for the analytical study (forward modeling) of wave propagation in layered media. The relevant characteristics of the results are next succinctly described: For the bridge: the theoretical fundamental frequency of vibration was 3.10 Hz., and the estimated experimental fundamental vibration frequency was 3.30 Hz. For the site characterization, our results are described starting at the north end of the bridge going through its south end: (i) The site S1_2, which is the site where the soil was artificially compacted, has a dominant frequency of 2.5 Hz and an average shear wave velocity of 195 m/s. (ii) For sites S3_1 and S2_4, the dominant frequency was 1.5 Hz and the average shear wave velocity was 115 m/s and 123 m/s, respectively. (iii) Site S2_2, the dominant frequency was 3.5 Hz and an average shear wave velocity 275 m/s. (iv) Site S2_5, in this site two clear peaks at frequencies of 1.5 and 3.75 Hz were observed, regarding to the average shear wave velocity it was 128 m/s. (v) Site S2_3, the dominant frequency was 4.0 Hz and the average shear wave velocity was 346 m/s. All the experimental sites were in soils at natural conditions, but the site S1_2, which was artificially compacted. The soil characteristics along the 163 m length of the bridge, clearly shows a rigidity change of the soil sub-surface conditions. That condition is an indication that different amplifications of the ground response will probably be experienced, being in the range of the 4.0 Hz at the south-end side of the bridge, and 1.5 Hz on the portion of the north-end of the bridge. In no case the fundamental vibration frequency of the bridge matches the fundamental vibration frequency of the ground surface. However, they are somehow no too far apart each other

Effect of <em>Helicobacter pylori</em> on Tight Junctions in Gastric Epithelia

Molecular complexes grouped under the names of tight, adherent or gap junction regulate the flow of water, ions and macromolecules through epithelium paracellular spaces. The main constituents of tight junctions are claudins, a family of 26 different proteins whose expression and distribution are tissue specific but varies in tumors. A change in claudin 1, 3, 4, 5, 6, 7, 9 and 18 expression, that contributes to lose epithelial cohesion, has been associated to enhanced cell proliferation, migration, and invasiveness in gastric neoplastic tissue. Chronic inflammation process induced by H. pylori infection, a major risk factor for gastric cancer development, disrupts tight junctions via CagA gene, Cag pathogenicity island, and VacA, but the effect upon the epithelial barrier of H. pylori lipopolysaccharides or H. pylori-induced up-regulation of mTOR and ERK signaling pathways by microRNA-100 establishes new concepts of proof

Criteria to discriminate between wines aged in oak barrels and macerated with oak fragments

Wine aging in barrels is carried out to increase stability and achieve more complex aromas. In the last few years, however, the practice of macerating wine with small fragments of toasted oak (chips) has become increasingly common. This conveys similar tastes, aromas, and wooden notes to the wine as those obtained with traditional barrel aging, but much faster and at a fraction of the cost. Without proper regulation, this could lead to fraud if wine macerated with chips is offered as barrel aged wine. In the present study, 75 volatile compounds have been determined by applying gas chromatography–mass spectrometry (MS) and flame ionization detection (FID). It has been found that compounds directly related to the wood have greater discriminative power for telling apart wines aged in barrels from those macerated with oak fragments, but no single compound permits flawless classification. Therefore, we have studied the effect of the addition of oak fragments of different origins, different oak types, different formats and subjected to different toasting processes on a set of 231 samples from 6 Spanish Denominations of Origin wines (DOs), and compared them to those same wines aged in oak barrels. In light of the results, we have developed a set of criteria which allows distinguishing with high degree of accuracy between wines which have been aged in barrels and those macerated with oak fragments. The application of these criteria to different wines allows correct classification in over 90% of cases.Peer ReviewedPublishe

Generic utilities in chronic obstructive pulmonary disease patients stratified according to different staging systems.

Background To determine generic utilities for Spanish chronic obstructive pulmonary disease (COPD) patients stratified by different classifications: GOLD 2007, GOLD 2013, GesEPOC 2012 and BODEx index. Methods Multicentre, observational, cross-sectional study. Patients were aged ≥40 years, with spirometrically confirmed COPD. Utility values were derived from EQ-5D-3 L. Means, standard deviations (SD), medians and interquartile ranges (IQR) were computed based on the different classifications. Differences in median utilities between groups were assessed by non-parametric tests. Results 346 patients were included, of which 85.5% were male with a mean age of 67.9 (SD = 9.7) years and a mean duration of COPD of 7.6 (SD = 5.8) years; 80.3% were ex-smokers and the mean smoking history was 54.2 (SD = 33.2) pack-years. Median utilities (IQR) by GOLD 2007 were 0.87 (0.22) for moderate; 0.80 (0.26) for severe and 0.67 (0.42) for very-severe patients (p 2: 0.89 (0.20); group 34: 0.80 (0.27); group 56: 0.67 (0.29); group 79: 0.41 (0.31). All comparisons were significant (p 4 and 56. Conclusion Irrespective of the classification used utilities were associated to disease severity. Some clinical phenotypes were associated with worse utilities, probably related to a higher frequency of exacerbations. GOLD 2007 guidelines and BODEx index better discriminated patients with a worse health status than GOLD 2013 guidelines, while GOLD 2013 guidelines were better able to identify a smaller group of patients with the best health

Progesterone regulates corticosterone elevation and alterations in spatial memory and exploratory behavior induced by stress in Wistar rats

The hippocampus is sensitive to high levels of glucocorticoids during stress responses; it suffers biochemical and cellular changes that affect spatial memory and exploratory behavior, among others. We analyzed the influence of the neurosteroid progesterone (PROG) on stress-induced changes in urinary corticosterone (CORT) levels, spatial memory and exploratory behavior.Castrated adult male rats were implanted with PROG or vehicle (VEHI),and then exposed for ten days to chronic stress created by overcrowding or ultrasonic noise. PROG and CORT levels were assessed in urine using highperformanceliquid chromatography (HPLC). Implanted PROG inhibited the rise of stress-induced CORT, prevented spatial memory impairment in the Morris water maze, and eliminated increased exploratory behavior in the hole-board test. These results suggest a protective role of PROG, possibly mediated by its anxiolytic mechanisms, against corticosteroids elevation and the behavioral deficit generated by stressful situations

erbB expression changes in ethanol and 7, 12- dimethylbenz (a) anthracene-induced oral carcinogenesis

Objetive: The aim of this study was to determine erbB expression in normal mucosa, oral dysplasia, and invasive carcinomas developed in the hamster's buccal pouch chemical carcinogenesis model. Study design: Fifty Syrian golden hamsters were equally divided in five groups (A-E); two controls and three experi - mental group exposed to alcohol, DMBA, or both for 14 weeks. Number of tumors per cheek, volume, histological condition, erbB expression were determined and results were analyzed by the Mann-Whitney U and Dunn's test. Results: Control groups and those exposed to alcohol (A, B and C respectively) only presented clinical and histo - logical normal mucosa; while those exposed to DMBA or DMBA plus alcohol (D and E groups) developed dys - plasia and invasive carcinomas. erbB2, erbB3, and erbB4 increased their expression in alcohol-exposed mucosa, dysplasia, and invasive carcinomas. We observed a similar expression level for erbB2 in dysplasia and carcinomas; while, erbB3 and erbB4 were similar only in carcinomas. Conclusion: The DMBA and alcohol can be considered as carcinogen and promoter for oral carcinogenesis. The erbB expression is different according to their histological condition, suggesting differential participation of the erbB family in oral carcinogenesis induced by alcohol and DMBA

Luminescent Devices Based on Silicon-Rich Dielectric Materials

Luminescent silicon‐rich dielectric materials have been under intensive research due to their potential applications in optoelectronic devices. Silicon‐rich nitride (SRN) and silicon‐rich oxide (SRO) films have been mostly studied because of their high luminescence and compatibility with the silicon-based technology. In this chapter, the luminescent characteristics of SRN and SRO films deposited by low‐pressure chemical vapor deposition are reviewed and discussed. SRN and SRO films, which exhibit the strongest photoluminescence (PL), were chosen to analyze their electrical and electroluminescent (EL) properties, including SRN/SRO bilayers. Light emitting capacitors (LECs) were fabricated with the SRN, SRO, and SRN/SRO films as the dielectric layer. SRN‐LECs emit broad EL spectra where the maximum emission peak blueshifts when the polarity is changed. On the other hand, SRO‐LECs with low silicon content (~39 at.%) exhibit a resistive switching (RS) behavior from a high conduction state to a low conduction state, which produce a long spectrum blueshift (~227 nm) between the EL and PL emission. When the silicon content increases, red emission is observed at both EL and PL spectra. The RS behavior is also observed in all SRN/SRO‐LECs enhancing an intense ultraviolet EL. The carrier transport in all LECs is analyzed to understand their EL mechanism