Centro de Estudios de Mecánica Computacional y Métodos Numéricos en la Ingeniería (CIMNE)
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Centro de Estudios de Mecánica Computacional y Métodos Numéricos en la Ingeniería (CIMNE)
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Ítem Acceso Abierto New features for neuron classification(2018-04-28) Hernández Pérez, Leonardo Agustin; Delgado Castillo, Duniel; Martín Pérez, Rainer; Orozco Morales, Rubén; Lorenzo Ginori, Juan Valentín; Universidad Central "Marta Abreu" de Las Villas. Dpto de Automática; Empresa de Telecomunicaciones de Cuba S.A, Santa Clara, Villa Clara, CubaThis paper addresses the problem of obtaining new neuron features capable of improving results of neuron classification. Most studies on neuron classification using morphological features have been based on Euclidean geometry. Here three onedimensional (1D) time series are derived from the three-dimensional (3D) structure of neuron instead, and afterwards a spatial time series is finally constructed from which the features are calculated. Digitally reconstructed neurons were separated into control and pathological sets, which are related to three categories of alterations caused by epilepsy, Alzheimer’s disease (long and local projections), and ischemia. These neuron sets were then subjected to supervised classification and the results were compared considering three sets of features: morphological, features obtained from the time series and a combination of both. The best results were obtained using features from the time series, which outperformed the classification using only morphological features, showing higher correct classification rates with differences of 5.15, 3.75, 5.33% for epilepsy and Alzheimer’s disease (long and local projections) respectively. The morphological features were better for the ischemia set with a difference of 3.05%. Features like variance, Spearman auto-correlation, partial auto-correlation, mutual information, local minima and maxima, all related to the time series, exhibited the best performance. Also we compared different evaluators, among which ReliefF was the best ranked.Ítem Acceso Abierto Metal artifact reduction by morphological image filtering for computed tomography(2018-06-01) Rodriguez-Gallo Guerra, Yakdiel; Perez Diaz, Marlen; Orozco Morales, Rubén; Universidad Central "Marta Abreu" de Las Villas. Dpto de AutomáticaWhen metal implants are present in the field of measurement, artifacts degrade image quality. Metal artifact reduction (MAR) methods produce images with improved quality leading to confident and reliable clinical diagnosis. Cur-rently, there are many methods developed, but no generally accepted solution to this issue has been found. In this work we propose a morphological image filter-ing approach for metal artifact reduction (MIFMAR) algorithm for image quality improvement. MIFMAR performance was compared with three well-known MAR methods, which are linear interpolation (LI), normalized metal artifact reduction (NMAR) and frequency split metal artifact reduction (FSMAR), using clinical studies. The methods were applied to images acquired from 30 clinical studies of patients with metallic implants. Image quality was evaluated by three experienced radiologists completely blinded to the information about if the image was processed or not to suppress the artifacts. They graded image quality in a five points-scale, where zero is an index of clear artifact presence, and five, a whole artifact suppression. Image quality on images were compared using the non-parametric Friedman-ANOVA test. Inter-observer agreement was evaluated using linear-weighted κ test. MIFMAR ensures efficient reduction of metal artifacts with high image quality, preserving all of tissues and details in CT images. Image quality and diagnostic scores improved significantly (p < 0.01) with good inter-observer agreement. MIFMAR is computationally inexpensive compared with other methods and does not use raw CT data.Ítem Acceso Abierto Gradient image smoothing for metal artifact reduction (GISMAR) in computed tomography(2019-03-25) Rodriguez-Gallo Guerra, Yakdiel; Orozco Morales, Rubén; Perez Diaz, Marlen; Universidad Central "Marta Abreu" de Las Villas. Dpto de AutomáticaMetal artifacts can impair accurate diagnosis, and degrade the image quality and diagnostic value of CT-slices. In this work we propose a novel gradient image smoothing for metal artifact reduction (GISMAR) algorithm for image quality improvement in patients with hip implants, dental fillings, DBS implants and permanent seed implants. Using Image Smoothing via L0 Gradient Minimization method, a global thresholding method, and the principle of NMAR method, the authors developed a new MAR method that does not depend on access to raw projection data. To validate the authors' approach, 2D-CT data from twenty-two patients with different metal implants were used and processed by GISMAR and three more well- known algorithms. In order to evaluate metal artifact reduction, mean CT number (HU and SD) was calculated as well as a subjective analysis with three expert observers. Image quality on images was compared using the non-parametric Friedman-ANOVA test. We conclude that GISMAR method can efficiently reduce metal artifacts using CT-slice, does not introduce new artifacts, while preserving anatomical structures.Ítem Acceso Abierto Computer-Aided Detection Systems for Digital Mammography(2019-10-02) Perez Diaz, Marlen; Orozco Morales, Rubén; Suarez Aday, Ernesto Daniel; Pirchio, Rosario; Universidad Central "Marta Abreu" de Las Villas. Dpto de Automática; Medical Physics Department, Atomic Energy National Commission, Buenos Aires, ArgentinaMammography is the typical diagnostic test for early detection of breast cancer. The presence of microcalcifications and masses in the images may be an indicator of the disease. The microcalcifications size is very small, so, in many cases, they are not visible from medical images by radiologists. On the other hand, masses can be also undetectable if image contrast is not good enough. The computer-aided detection (CAD) systems are useful tools in facilitating the physician´s diagnosis. The CAD system proposed in this work is aimed at improving image quality based on image processing. On these improved images, it segments the mammary gland and highlights the presence of microcalcifications and masses. The system improves image contrast by means of convolution filters, it also eliminates artifacts by means of morphological opening and closing and Laplacian filtering, and uses entropy-based methods for segmentation of the gland and morphological filtering and histogram readjustment to enhance microcalcifications in the image. Masses are detected using an iterative contrast increase method. The system was tested with an annotated database (DB) MIAS, in oblique lateral views of glandular, glandular-dense and predominantly adipose breasts, which included images of malignant and benign lesions and other breast images without them. The system was evaluated with respect to the DB annotation, for a sample of 115 images. The performance of the system revealed a sensitivity of 93.2%, a specificity of 85.3%, a precision of 90.4% and an accuracy of 92%.Ítem Acceso Abierto Color Features Extraction and Classification of Digital Images of Erythrocytes Infected by Plasmodium berghei(2019-11) Lorenzo Ginori, Juan Valentín; Meneses Marcel, Alfredo; Mollineda Diogo, Niurka; Orozco Morales, Rubén; Sifontes Rodríguez, Sergio; Chinea Valdés, Lyanett; Izquierdo Torres, Yanela; Universidad Central "Marta Abreu" de Las Villas. Dpto de Automática; Universidad Central "Marta Abreu" de Las Villas. Centro de Bioactivos Químicos,The development of antimalarial drugs requires performing laboratory experiments that include the analysis of blood smears infected with Plasmodium berghei. Analyzing visually the resulting microscopy images is usually a slow and tedious task prone to errors due to fatigue and subjectivity of the analysts. These facts motivated the creation of digital image processing systems to automate the aforementioned analysis. We present in this work a computer vision solution which processes microscopy images of blood smears. This system performs tasks like illumination correction, color compensation, image segmentation including separation of clumped objects and the extraction and selection of color features. Then a set of classifiers was tested to find the best one in terms of classification results. Here a new feature named pixels fraction was introduced and a number of other color features were extracted, from which a subset was selected for the classification of the cells into either normal or infected. The classifiers tested for this application were: support vector machines (SVM), K-nearest neighbors (KNN), J48, Random Forest (RF), Naïve Bayes and linear discriminant analysis (LDA). All of them were evaluated in terms of their performance expressed as correct classification rate, sensitivity, specificity, F-measure and area under Receiver Operating Characteristic (ROC) curve (AUC). The usefulness of the pixels fraction as a new and effective feature was demonstrated by the experimental results. In regard of classifiers, J48 and Random Forest showed the best results.Ítem Acceso Abierto Relaciones Públicas: tres facetas de la comunicación en el sector turístico(2019-12) García Hernández, Georgete; Angel Rodríguez, Naliet; Álvarez García, Nélida Esther; Universidad Central "Marta Abreu" de Las Villas. Facultad de Construcciones. Centro de Estudios de Mecánica Computacional aplicada a la IngenieríaLa globalización ha permitido que la influencia de la comunicación en todas las esferas de la vida del hombre sea, en ocasiones, un desafío para los sectores económico político y social. Por supuesto que en el aspecto económico, el sector turístico no está fuera de su alcance, pues es a través de la comunicación que se refuerza positivamente la imagen de una organización o producto para lo que se requiere la utilización de nuevas herramientas por parte de las Relaciones Públicas. Estas desempeñan una importante función en el sector turístico como parte del proceso de intercambio entre destinos y organizaciones y diferentes públicos estratégicos. Actualmente, su accionar dentro de este se ve condicionado por diversos factores: la optimización de la labor del cliente interno y la correcta promoción del producto encaminado a la satisfacción de las necesidades cada vez más exigentes de su público. Para ello se hace necesario que los especialistas en relaciones públicas conozcan algunas herramientas comunicativas que le permitan llevar a cabo una adecuada gestión de la comunicación. Ante lo expuesto, este articulo tiene como objetivo dar a conocer tres facetas de la comunicación que se insertan en la labor de las Relaciones Públicas en el sector turístico: la comunicación institucional, la comunicación vista desde el marketing y la comunicación intercultural, así como la importancia de estas en la gestión de promoción y en la proyección de estrategias que permitan situar el producto en el mercado, elevar su nivel a estándares competitivos y lograr la transformación social.Ítem Acceso Abierto New Morphological Features Based on the Sholl Analysis for Automatic Classification of Traced Neurons(2020) López Cabrera, José Daniel; Hernández Pérez, Leonardo Agustín; Orozco Morales, Rubén; Lorenzo Ginori, Juan Valentín; Universidad Central "Marta Abreu" de Las Villas. Dpto de Automática.; Universidad Central "Marta Abreu" de Las Villas. Centro de Investigaciones de la Informática.; Empresa de Telecomunicaciones de Cuba S.A,Background: This article addresses the automatic classification of reconstructed neurons through their morphological features. The purpose was to extend the capabilities of the L-Measure software. Methods: New morphological features were developed, based on modifications of the conventional Sholl analysis. The lengths of the compartments, as well as their volumes, were added to the features used in the classical analysis in order to improve the results during automatic neuron classification. FSM were used to obtain subsets of lower cardinality from the full feature sets and the usefulness of these subsets was tested through their use in supervised classification tasks. The study was based on two types of neurons belonging to mice: pyramidal and GABAergic interneurons. Furthermore, a set of pyramidal neurons belonging to Later 4 and Layer 5 was analyzed. Results: RF classifier shown the best performance combined with a Wrapper method.U-WNAD set allowed to obtain higher values than WN, A and D in all cases and better results than LM for the filters and wrappers FSM. U-LM-WNAD set, led to the highest AUC values for all the FSM studied. Similar results for different regions of cortex were obtained. Comparison with Existing Methods The new features exhibited high discriminatory power with which the values of AUC and Acc obtained in the experiments exceeded those obtained using only the features provided by L-Measure. Conclusions: The highest values of AUC and Acc were obtained from the sets U-WNAD and U-LM-WNAD, evidencing the discriminatory power of the new proposed features.Ítem Acceso Abierto Factores cognitivos y afectivos en la enseñanza y aprendizaje del inglés como lengua extranjera(2020) Angel Rodríguez, Naliet; Universidad Central "Marta Abreu" de Las Villas. Facultad de Construcciones. Centro de Estudios de Mecánica Computacional aplicada a la IngenieríaEl dominio de linglés reclama la adquisición de la competencia comunicativa del estudiante a través del proceso enseñanza aprendizaje en su intento por satisfacer las demandas de un profesional competente. Utilizarlo con fines comunicativos es una capacidad cada vez más exigida en el competitivo mundo laboral; pero este propósito, como el de toda lengua extranjera incluye un largo proceso de apropiación del idioma, camino cargado de obstáculos para el alumno quien va adquiriendo herramientas gramaticales, léxicas, funcionales y culturales,y a su vez va desarrollando las estrategias de aprendizaje y habilidades que les permiten aumentar su competencia lingüística y comunicativa. Es objetivo de los autores socializar algunos factores cognitivos y afectivos que favorecen este proceso, a partir de sus experiencias docentes.Ítem Acceso Abierto Importancia del idioma Inglés en el campo de la medicina(2020) Angel Rodríguez, Naliet; Universidad Central "Marta Abreu" de Las Villas. Facultad de Construcciones. Centro de Estudios de Mecánica Computacional aplicada a la IngenieríaEn la actualidad, el inglés es considerado el idioma global para la comunicación científica. En las últimas décadas, se ha enseñado en diferentes instituciones para satisfacer las necesidades académicas y profesionales específicas. Este tipo de aprendizaje se conoce como inglés con Fines Específicos. El inglés con Fines Médicos, es un subtipo de ESP, el cual es esencial para satisfacer las necesidades académicas y profesionales de estudiantes de medicina y doctores. Ha alcanzado una posición incuestionable en el contexto de la medicina, ya que gran parte de la información médica actualizada que se encuentra en libros, artículos, documentos y periódicos está en este idioma. Es objetivo de los autores demostrar la importancia que tiene para los estudiantes de medicina y doctores el aprendizaje del inglés con fines médicos para poder desarrollarse en los distintos contextos médicos.Ítem Acceso Abierto Estimación en línea del efecto del oleaje para el control de un vehículo marino(2020-01) Garcia Garcia, Delvis; Peña Martín, Jorge; Hernández Santana, Luis; Orozco Morales, Rubén; Universidad Central "Marta Abreu" de Las Villas. Dpto de AutomáticaEl oleaje generado por el viento es un fenómeno totalmente aleatorio y constituye una de las principales perturbaciones que afectan el funcionamiento de los Vehículos Autónomos Subacuáticos (VAS) que operan a poca profundidad y en zonas costeras. Con el objetivo de atenuar el efecto indeseable de esta perturbación sobre el sistema de control de los VAS se filtran las mediciones obtenidas de los sensores haciendo uso de la frecuencia de incidencia del oleaje. Desarrollar un estimador capaz de brindar el valor de la frecuencia de incidencia del oleaje en tiempo real; mediante el método de Identificación Algebraica, constituye la finalidad de este trabajo. En el diseño del estimador algebraico propuesto se emplea una ecuación diferencial lineal para representar el espectro de las olas, lo cual simplifica el procedimiento matemático. Las simulaciones llevadas a cabo; tanto con datos simulados como con datos de un experimento real en el mar, muestran los excelentes resultados del estimador en cuanto a la exactitud en el valor final estimado y el tiempo de la estimación. Adicionalmente, se muestra el empleo de la estimación de la frecuencia de incidencia del oleaje para ajustar adecuadamente las técnicas de filtrado implementadas previamente para el vehículo, lo que trae consigo una reducción considerable de las vibraciones y del consumo de energía del sistema de timones del vehículo.Ítem Acceso Abierto Spectral Signature of Brown Rust and Orange Rust in Sugarcane(2020-07) Luís Soca Muñoz, Jorge; Rodríguez Machado, Eniel; Aday Díaz, Osmany de la Caridad; Hernández Santana, Luis; Orozco Morales, Rubén; Universidad Central "Marta Abreu" de Las Villas. Dpto de Automática; Estación Territorial de Investigaciones de la Caña de Azúcar (ETICA Centro Villa Clara), Instituto de Investigaciones de la Caña de AzúcarPrecision agriculture, making use of the spatial and temporal variability of cultivable land, allows farmers to refine fertilization, control field irrigation, estimate planting productivity, and detect pests and disease in crops. To that end, this paper identifies the spectral reflectance signature of brown rust (Puccinia melanocephala) and orange rust (Puccinia kuehnii), which contaminate sugar cane leaves (Saccharum spp.). By means of spectrometry, the mean values and standard deviations of the spectral reflectance signature are obtained for five levels of contamination of the leaves in each type of rust, observing the greatest differences between healthy and diseased leaves in the red (R) and near infrared (NIR) bands. With the results obtained, a multispectral camera was used to obtain images of the leaves and calculate the Normalized Difference Vegetation Index (NDVI). The results identified the presence of both plagues by differentiating healthy from contaminated leaves through the index value with an average difference of 11.9% for brown rust and 9.9% for orange rust.Ítem Acceso Abierto Revisión crítica sobre la identificación de COVID-19 a partir de imágenes de rayos-X de tórax usando técnicas de inteligencia artificial(2020-10) López Cabrera, José Daniel; Portal Díaz, Jorge Armando; Orozco Morales, Rubén; Pérez Díaz, Marlen; Universidad Central "Marta Abreu" de Las Villas. Dpto de AutomáticaA partir del surgimiento de la actual pandemia de COVID-19, la comunidad científica ha aunado esfuerzos para mitigar su alcance. La identificación temprana de la enfermedad, así como la evaluación de su evolución es una tarea primordial para la aplicación oportuna de protocolos médicos. En este empeño, el uso de imágenes médicas de los pulmones presenta una valiosa información usada por los especialistas. Específicamente, las imágenes de rayos X de tórax han sido el foco de atención de muchas investigaciones que aplican técnicas de inteligencia artificial para la clasificación automática de esta enfermedad. Los resultados alcanzados en el tema hasta la fecha son prometedores. No obstante, estas investigaciones contienen errores que deben corregirse para obtener modelos apropiados en el uso clínico. En esta investigación se discuten los problemas encontrados en la literatura científica actual, al usar técnicas de inteligencia artificial para la clasificación automática de COVID-19 usando imágenes de rayos X de tórax. Se evidencia que en la mayoría de los trabajos revisados se aplica un protocolo de evaluación incorrecto, lo cual conlleva a sobreestimar los resultados.Ítem Acceso Abierto Inpainting‑filtering for metal artifact reduction (IMIF‑MAR) in computed tomography(2021) Rodriguez-Gallo Guerra, Yakdiel; Orozco Morales, Rubén; Perez Diaz, Marlen; Universidad Central "Marta Abreu"de las Villas. Facultad de Eléctrica. Departamento de automática.The reduction of metal artifacts remains a challenge in computed tomography because they decrease image quality, and consequently might affect the medical diagnosis. The objective of this study is to present a novel method to correct metal artifacts based solely on the CT-slices. The proposed method consists of four steps. First, metal implants in the original CTslice are segmented using an entropy based method, producing a metal image. Second, a prior image is acquired using three transformations: Gaussian filter, Parisotto and Schoenlieb inpainting method with the Mumford-Shah image model and L0 Gradient Minimization method (L0GM). Next, based on the projections from the original CT-slice, prior image and metal image, the sinogram is corrected in the traces affected by metal in the process called normalization and denormalization. Finally, the reconstructed image is obtained by FBP and a Nonlocal Means (NLM) filtering. The efficacy of the algorithm is evaluated by comparing five image quality metrics of the images and by inspecting regions of interest (ROI). Phantom data as well as clinical datasets are included. The proposed method is compared with three established metal artifact reduction (MAR) methods. The results from a phantom and clinical dataset show the visible reduction of artifacts. The conclusion is that IMIF-MAR method can reduce streak metal artifacts effectively and avoid new artifacts around metal implants, while preserving the anatomical structures. Considering both clinical and phantom studies, the proposed MAR algorithm improves the quality of clinical images affected by metal artifacts, and could be integrated in clinical setting.Ítem Acceso Abierto Reducción de artefactos de anillo en tomografía computarizada(2021-03) Borroto Hernández, Gimel; Pacheco Chanfrau, Yankiel Aradih; Perez Diaz, Marlen; Orozco Morales, Rubén; Dpto. de Control Automático, Universidad Central "Marta Abreu" de Las VillasLa tomografía computarizada es una técnica no invasiva ampliamente utilizada para la detección de problemas de salud. La calidad de imagen puede ser afectada por artefactos de anillos debidos a la falta de homogeneidad en los detectores del tomógrafo. En esta investigación se comparan siete métodos para la reducción de artefactos de anillos: Métodos de variaciones totales (TV), Variación total unidireccional (UTV), Modelo disperso direccional con filtrado L0 (DL0SM), Modelo de variación total–espectral anisótropo (ASSTV), Descomposición de imagen de bajo rango (LRSID), Método estático (SGE) y Método de filtrado por transformadas de Wavelet y Fourier (WF). Estos métodos se basan en la transformación del plano cartesiano al polar con centro de rotación en el centro de los mismos, los cuales son trasformados a líneas y luego estas son reducidas. Fueron programados en lenguaje Matlab. Su desempeño fue evaluado a partir del análisis de cuatro métricas objetivas de calidad de imagen y el criterio subjetivo de dos especialistas. Se demostró que el método de mejor desempeño entre los probados es el denominado UTV.Ítem Acceso Abierto Economic burden of premature mortality from systemic lupus erythematosus in Cuba(2021-04-10) Angel Rodríguez, Naliet; Hernandez Negrin, HalbertMortality statistics are traditionally used to quantify the burden of disease and to determine the relative importance of the various causes of death. One of the most frequently used indicators to quantify the economic burden of disease is the years of potential productive life lost (YPPLL). Although it has been demonstrated that mortality due to systemic lupus erythematosus (SLE) is increasing in Latin America,2 there is limited research assessing its socioeconomic burden in Cuba. Our aim was to estimate the years of potential productive life lost (YPPLL) due to premature mortality from SLE in Cuba, between 2001-2018.Ítem Acceso Abierto Racial disparities in renal disease-related mortality in Cuban patients with systemic lupus erythematosus(2021-04-12) Angel Rodríguez, Naliet; Hernandez Negrin, HalbertBy and large, systemic lupus erythematosus (SLE) is more prevalent and with less favorable outcomes in non-white populations. To overcome these differences and reduce the short-, medium-, and long-term impact of SLE in disadvantaged populations, it is essential to increase awareness of the disease, improve access to health care, and provide care to these patients in a consistent manner, regardless of the severity of their disease. In this context, premature mortality related to renal involvement in SLE patients is of particular concern. Despite these facts, little research has been conducted in Cuba aimed at understanding the unequal impact of renal disease on mortality in white and non-white SLE patients. Our aim was to identify racial disparities in renal disease -related mortality in Cuban patients who died from SLE.Ítem Acceso Abierto Current limitations to identify COVID-19 using artificial intelligence with chest X-ray imaging(Part II). The shortcut learning problem(2021-10-10) López Cabrera, José Daniel; Orozco Morales, Rubén; Portal Díaz, Jorge Armando; Perez Diaz, Marlen; Lovelle Enríquez, Orlando; Universidad Central "Marta Abreu" de Las Villas. Dpto de Automática; Departamento Imagenología Hospital Manuel Fajardo RiveroSince the outbreak of the COVID-19 pandemic, computer vision researchers have been working on automatic identification of this disease using radiological images. The results achieved by automatic classification methods far exceed those of human specialists, with sensitivity as high as 100% being reported. However, prestigious radiology societies have stated that the use of this type of imaging alone is not recommended as a diagnostic method. According to some experts the patterns presented in these images are unspecific and subtle, overlapping with other viral pneumonias. This report seeks to evaluate the analysis the robustness and generalizability of different approaches using artificial intelligence, deep learning and computer vision to identify COVID-19 using chest X-rays images. We also seek to alert researchers and reviewers to the issue of “shortcut learning”. Recommendations are presented to identify whether COVID-19 automatic classification models are being affected by shortcut learning. Firstly, papers using explainable artificial intelligence methods are reviewed. The results of applying external validation sets are evaluated to determine the generalizability of these methods. Finally, studies that apply traditional computer vision methods to perform the same task are considered. It is evident that using the whole chest X-Ray image or the bounding box of the lungs, the image regions that contribute most to the classification appear outside of the lung region, something that is not likely possible. In addition, although the investigations that evaluated their models on data sets external to the training set, the effectiveness of these models decreased significantly, it may provide a more realistic representation as how the model will perform in the clinic. The results indicate that, so far, the existing models often involve shortcut learning, which makes their use less appropriate in the clinical setting.Ítem Acceso Abierto Automated System for the Detection of Lung Nodules(2021-11) Martinez Machado, Elizabeth; Perez Diaz, Marlen; Orozco Morales, Rubén; Universidad Central "Marta Abreu"de las Villas. Facultad de Eléctrica. Departamento de automática.Lung cancer is the most frequent cause of cancer mortality in the world. The diagnostic procedure usually begins with a chest X-ray; however, it is difficult to interpret due to the set of anatomical structures overlapped. Computer-aided detection (CAD) systems are a diagnostic aid tool for radiologists. In the present work a CAD system is proposed for the detection of lung nodules on chest radiographs. Methods such as convolution, local normalization and homomorphic filters are used to pre-process images, using a multi-level threshold method supported by morphological operations for anatomical segmentation. This is followed by a candidate nodule detector using the local slidingband convergence filter. The candidate nodules are segmented using an adaptive threshold based on distance. A set of characteristics for each candidate are calculated based on the segmentation. The system was tested by a free available database (DB) of 247 images, of which 154 are pulmonary nodules (100 malignant and 54 benign cases and 93 nodules). The results obtained indicate that the system is able of detecting 98.7% of the nodules of the DB with an average of 56.08 detections per image. Two false positive were obtained due to lung segmentation.Ítem Acceso Abierto A Model Describing the Rhetorical Structure of the Abstracts of Cardiology Research Articles in English(2021-11-25) Angel Rodríguez, Naliet; Bernal Díaz, Pedro Santiago; Rodriguez Ruiz, Mayra; Universidad Central "Marta Abreu"de las Villas. Facultad de Construcciones. CIMNE.; Universidad Central "Marta Abreu"de las Villas. Centro de Idiomas; Universidad Central "Marta Abreu"de las Villas. Facultad de humanidades. Departamento de Lengua InglesaThe Abstract section of the research article (RA) is particularly important because it offers different communicative functions. In the medical field, English has also gained the status of Lingua Franca since most of the medical journals are published in English and principal contributions in medicine and science are published in this language as well. Therefore, it is essential for scientists in the field of medicine to communicate the results of their research in English in order to gain international recognition.Ítem Acceso Abierto A Model Describing the Rhetorical Structure and Linguistic Elements of the Abstract Section of Cardiology Research Articles in English(Editorial Feijóo, 2022-02-22) Angel Rodríguez, Naliet; Bernal Díaz, Pedro Santiago; Rodriguez Ruiz, Mayra; Vasconcelos Alonso, Lucia; Velázquez Brito, Julia del Carmen; Universidad Central "Marta Abreu" de Las Villas. Facultadad de Construcciones. CIMNE; Universidad Central "Marta Abreu" de Las Villas. Centro de Idiomas; Universidad Central "Marta Abreu" de Las Villas. Departamento de Lengua Inglesa; Universidad Central "Marta Abreu" de Las Villas. Centro de Idiomas; Universidad de Ciencias Medicas de Villa Clara. Facultad de Psicologia; Artiles Castro, MiriamThe Abstract section is particularly important because it offers different communicative functions such as presenting, describing, stating, summarizing evaluating and sometimes, recommending. That is why, the aim of the present study is to propose a model describing the rhetorical structure and linguistic elements used in the Abstract section of Cardiology research articles in English. To accomplish this purpose, a special corpus of ninety research article abstracts from three specialized Cardiology journals was compiled and processed by AntMover 1.10 (2016) and AntConc 3.5.8 Window (2019), two corpus analysis softwares. As a result, it was designed a rhetorical model consisting in five moves in the Abstract section. The designed model will contribute to improve the academic writing of research articles abstracts in English by Cuban cardiologists. It will also help them to meet the international scientific community demands of their publications. Furthermore, the findings will make an important contribution to the field of ESP pedagogy as they offer authentic material, which could be used for the teaching and learning of English writing.