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1.
PeerJ Comput Sci ; 9: e1723, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38192446

RESUMEN

Glioblastoma is a highly malignant brain tumor with a life expectancy of only 3-6 months without treatment. Detecting and predicting its survival and grade accurately are crucial. This study introduces a novel approach using transfer learning techniques. Various pre-trained networks, including EfficientNet, ResNet, VGG16, and Inception, were tested through exhaustive optimization to identify the most suitable architecture. Transfer learning was applied to fine-tune these models on a glioblastoma image dataset, aiming to achieve two objectives: survival and tumor grade prediction.The experimental results show 65% accuracy in survival prediction, classifying patients into short, medium, or long survival categories. Additionally, the prediction of tumor grade achieved an accuracy of 97%, accurately differentiating low-grade gliomas (LGG) and high-grade gliomas (HGG). The success of the approach is attributed to the effectiveness of transfer learning, surpassing the current state-of-the-art methods. In conclusion, this study presents a promising method for predicting the survival and grade of glioblastoma. Transfer learning demonstrates its potential in enhancing prediction models, particularly in scenarios with limited large datasets. These findings hold promise for improving diagnostic and treatment approaches for glioblastoma patients.

2.
Sensors (Basel) ; 22(4)2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-35214392

RESUMEN

Mathematical modeling and data-driven methodologies are frequently required to optimize industrial processes in the context of Cyber-Physical Systems (CPS). This paper introduces the PipeGraph software library, an open-source python toolbox for easing the creation of machine learning models by using Directed Acyclic Graph (DAG)-like implementations that can be used for CPS. scikit-learn's Pipeline is a very useful tool to bind a sequence of transformers and a final estimator in a single unit capable of working itself as an estimator. It sequentially assembles several steps that can be cross-validated together while setting different parameters. Steps encapsulation secures the experiment from data leakage during the training phase. The scientific goal of PipeGraph is to extend the concept of Pipeline by using a graph structure that can handle scikit-learn's objects in DAG layouts. It allows performing diverse operations, instead of only transformations, following the topological ordering of the steps in the graph; it provides access to all the data generated along the intermediate steps; and it is compatible with GridSearchCV function to tune the hyperparameters of the steps. It is also not limited to (X,y) entries. Moreover, it has been proposed as part of the scikit-learn-contrib supported project, and is fully compatible with scikit-learn. Documentation and unitary tests are publicly available together with the source code. Two case studies are analyzed in which PipeGraph proves to be essential in improving CPS modeling and optimization: the first is about the optimization of a heat exchange management system, and the second deals with the detection of anomalies in manufacturing processes.

3.
Aten Primaria ; 53(8): 102084, 2021 10.
Artículo en Español | MEDLINE | ID: mdl-33991761

RESUMEN

OBJECTIVE: To determine the unexpected return rate to the Primary Care Emergency Service of elderly patients over 65 years old within the following 72h of a previous visit, as well as to determine the clinical and assistance requirements of these patients. PROCEDURE: Retrospective and observational epidemiologic study. LOCATION: Cotolino's Primary Care Emergency Service in Cantabria, Spain. PARTICIPANTS: 1940 elderly patients over 65 years old were included. These patients returned to the Primary Care Emergency Service in 2016. MAIN DATA FOR THE STUDY: The dependent variable was the return rate to the Primary Care Emergency Service. The independent variables were socio-demographic characteristics, health details and medical assistance information. All data was collected from the Primary Care Emergency Service Management Office database. All variables were analysed applying Pearson's chi-squared test and Fisher's exact test, with statistical significance P≤.05. RESULTS: The rate of unexpected return was 2.3%. The average age was 77.4 years old (standard deviation (SD): 8.4), of which the 37.6% were male. The most frequent range of age was from 75 to 84 years old, with males being the predominant group. A history of polymedication was detected in 54.4% of the cases, as well as a medium cardiovascular risk within this group. Nursing professionals attended the 42.2% of these return cases (P<.001). Patients with dysnea (P=.015), scheduled care or scheduled injection returned with a higher frequency (P<.001). It was as well noticed a higher frequency of return for subsequent attention during the months of December and January (P<.001). CONCLUSIONS: The rate of unexpected return is low. The main causes why elderly patients returned to the service requiring urgent assistance were issues categorised as unspecific general health indicators and/or respiratory system illnesses. Our proposal is to develop specific protocols combining the work from both Geriatrics and Gerontology professionals, in order to improve the support to this group of population at every Primary Care Emergency Service.


Asunto(s)
Servicios Médicos de Urgencia , Geriatría , Anciano , Anciano de 80 o más Años , Servicio de Urgencia en Hospital , Humanos , Masculino , Atención Primaria de Salud , Estudios Retrospectivos , España
4.
Comput Methods Programs Biomed ; 202: 105968, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33631638

RESUMEN

BACKGROUND AND OBJECTIVE: Diabetes is a chronic pathology which is affecting more and more people over the years. It gives rise to a large number of deaths each year. Furthermore, many people living with the disease do not realize the seriousness of their health status early enough. Late diagnosis brings about numerous health problems and a large number of deaths each year so the development of methods for the early diagnosis of this pathology is essential. METHODS: In this paper, a pipeline based on deep learning techniques is proposed to predict diabetic people. It includes data augmentation using a variational autoencoder (VAE), feature augmentation using an sparse autoencoder (SAE) and a convolutional neural network for classification. Pima Indians Diabetes Database, which takes into account information on the patients such as the number of pregnancies, glucose or insulin level, blood pressure or age, has been evaluated. RESULTS: A 92.31% of accuracy was obtained when CNN classifier is trained jointly the SAE for featuring augmentation over a well balanced dataset. This means an increment of 3.17% of accuracy with respect the state-of-the-art. CONCLUSIONS: Using a full deep learning pipeline for data preprocessing and classification has demonstrate to be very promising in the diabetes detection field outperforming the state-of-the-art proposals.


Asunto(s)
Aprendizaje Profundo , Diabetes Mellitus , Bases de Datos Factuales , Diabetes Mellitus/diagnóstico , Humanos , Redes Neurales de la Computación
5.
Animals (Basel) ; 10(4)2020 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-32326214

RESUMEN

In vitro gas production systems are utilized to screen feed ingredients for inclusion in ruminant diets. However, not all in vitro systems are set up to measure methane (CH4) production, nor do all publications report in vitro CH4. Therefore, the objective of this study was to develop models to predict in vitro CH4 production from total gas and volatile fatty acid (VFA) production data and to identify the major drivers of CH4 production in these systems. Meta-analysis and machine learning (ML) methodologies were applied to a database of 354 data points from 11 studies to predict CH4 production from total gas production, apparent DM digestibility (DMD), final pH, feed type (forage or concentrate), and acetate, propionate, butyrate and valerate production. Model evaluation was performed on an internal dataset of 107 data points. Meta-analysis results indicate that equations containing DMD, total VFA production, propionate, feed type and valerate resulted in best predictability of CH4 on the internal evaluation dataset. The ML models far exceeded the predictability achieved using meta-analysis, but further evaluation on an external database would be required to assess generalization ability on unrelated data. Between the ML methodologies assessed, artificial neural networks and support vector regression resulted in very similar predictability, but differed in fitting, as assessed by behaviour analysis. The models developed can be utilized to estimate CH4 emissions in vitro.

6.
Sensors (Basel) ; 20(4)2020 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-32098446

RESUMEN

The aim of this paper was the detection of pathologies through respiratory sounds. The ICBHI (International Conference on Biomedical and Health Informatics) Benchmark was used. This dataset is composed of 920 sounds of which 810 are of chronic diseases, 75 of non-chronic diseases and only 35 of healthy individuals. As more than 88% of the samples of the dataset are from the same class (Chronic), the use of a Variational Convolutional Autoencoder was proposed to generate new labeled data and other well known oversampling techniques after determining that the dataset classes are unbalanced. Once the preprocessing step was carried out, a Convolutional Neural Network (CNN) was used to classify the respiratory sounds into healthy, chronic, and non-chronic disease. In addition, we carried out a more challenging classification trying to distinguish between the different types of pathologies or healthy: URTI, COPD, Bronchiectasis, Pneumonia, and Bronchiolitis. We achieved results up to 0.993 F-Score in the three-label classification and 0.990 F-Score in the more challenging six-class classification.


Asunto(s)
Redes Neurales de la Computación , Algoritmos , Humanos
7.
Animals (Basel) ; 9(11)2019 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-31653022

RESUMEN

The nutritive value of 26 agro-industrial by-products was assessed from their chemical composition, in vitro digestibility and rumen fermentation kinetics. By-products from sugar beet, grape, olive tree, almond, broccoli, lettuce, asparagus, green bean, artichoke, peas, broad beans, tomato, pepper, apple pomace and citrus were evaluated. Chemical composition, in vitro digestibility and fermentation kinetics varied largely across the by-products. Data were subjected to multivariate and principal component analyses (PCA). According to a multivariate cluster analysis chart, samples formed four distinctive groups (A-D). Less degradable by-products were olive tree leaves, pepper skins and grape seeds (group A); whereas the more degradable ones were sugar beet, orange, lemon and clementine pulps (group D). In the PCA plot, component 1 segregated samples of groups A and B from those of groups C and D. Considering the large variability among by-products, most of them can be regarded as potential ingredients in ruminant rations. Depending on the characteristic nutritive value of each by-product, these feedstuffs can provide alternative sources of energy (e.g., citrus pulps), protein (e.g., asparagus rinds), soluble fibre (e.g., sugar beet pulp) or less digestible roughage (e.g., grape seeds or pepper skin).

8.
Sensors (Basel) ; 19(12)2019 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-31216729

RESUMEN

This paper proposes a methodology for dealing with an issue of crucial practical importance in real engineering systems such as fault detection and recovery of a sensor. The main goal is to define a strategy to identify a malfunctioning sensor and to establish the correct measurement value in those cases. As study case, we use the data collected from a geothermal heat exchanger installed as part of the heat pump installation in a bioclimatic house. The sensor behaviour is modeled by using six different machine learning techniques: Random decision forests, gradient boosting, extremely randomized trees, adaptive boosting, k-nearest neighbors, and shallow neural networks. The achieved results suggest that this methodology is a very satisfactory solution for this kind of systems.

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