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1.
Biosci. j. (Online) ; 38: e38024, Jan.-Dec. 2022. ilus, mapas, tab, graf
Article in English | LILACS | ID: biblio-1395413

ABSTRACT

The biophysical characteristics of vegetative canopies, such as biomass, height, and canopy diameter, are of paramount importance for the study of the development and productive behavior of crops. Faced with a scarcity of studies aimed at estimating these parameters, the objective of this study was to evaluate the performance of artificial neural networks (ANNs) applied to Proximal Remote Sensing (PRS) to estimate biophysical characteristics of soybean culture. The data used to train and validate the ANNs came from an experiment composed of 65 plots with 30 x 30 m mesh, its development was carried out in the 2016/2017 crop in the Brazilian agricultural area. The evaluations were carried out at 30, 45, 60, and 75 days after sowing (DAS), monitoring the spatial and temporal variability of the biophysical characteristics of the soybean crop. Vegetation indexes were collected using canopy sensors. The accuracy and precision were determined by the coefficient of determination (R2) and the error of the forecasts by MAPE (Mean Absolute Percentage Error). PRS and ANNs showed high potential for application in agriculture, since they obtained good performance in the estimation of height (R2 = 0.89) and canopy diameter (R2 = 0.96), being fresh biomass (R2 =0.98) and dry biomass (R2 = 0.97) were the best-estimated variables.


Subject(s)
Soybeans/anatomy & histology , Neural Networks, Computer , Machine Learning
2.
Braz. arch. biol. technol ; 65: e22210711, 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1364439

ABSTRACT

Abstract: Microgrids (MD) is a new technology to improve efficiency, resilience, and reliability in the electricity sector. MD are most likely to have a clean energy generation, but the increase of microgrids with this kind of generation brings new challenges for energy management (EMS), especially concerning load uncertainties and variation of energy generation. In this context, this study has the main objective to propose a method of how to attend this matter, verifying the difference between the day before and real-time. The EMS proposed analyses the MD in real-time, calculating the deviation between dispatched and what was predicted to happen in the operation point in a three-dimensional analysis approach, considering renewable energy generation, battery State of Charge (SOC) and load curve. The system categorized the deviation in three possible quantities (small, medium, or high) and it acts accordingly. For the Next Operation Point predictor are used an artificial neural network (ANN) methodology. For the Decision Support System, it's used a fuzzy logic system to adjust the next operation point, and it uses a mixed-integer linear programming (MILP) approach when the deviation is too high, and the dispatched operation is unfeasible. Simulations with real data and information of a pilot project of MD are carried out to test and validate the proposed method. Results show that the methodology used to attend the matters of uncertainties and variation of energy generation. A reduction of operational cost is observed in the simulations.

3.
Article in Spanish | LILACS, CUMED | ID: biblio-1408108

ABSTRACT

Este artículo tuvo como propósito caracterizar el texto libre disponible en una historia clínica electrónica de una institución orientada a la atención de pacientes en embarazo. La historia clínica electrónica, más que ser un repositorio de datos, se ha convertido en un sistema de soporte a la toma de decisiones clínicas. Sin embargo, debido al alto volumen de información y a que parte de la información clave de las historias clínicas electrónicas está en forma de texto libre, utilizar todo el potencial que ofrece la información de la historia clínica electrónica para mejorar la toma de decisiones clínicas requiere el apoyo de métodos de minería de texto y procesamiento de lenguaje natural. Particularmente, en el área de Ginecología y Obstetricia, la implementación de métodos del procesamiento de lenguaje natural podría ayudar a agilizar la identificación de factores asociados al riesgo materno. A pesar de esto, en la literatura no se registran trabajos que integren técnicas de procesamiento de lenguaje natural en las historias clínicas electrónicas asociadas al seguimiento materno en idioma español. En este trabajo se obtuvieron 659 789 tokens mediante los métodos de minería de texto, un diccionario con palabras únicas dado por 7 334 tokens y se estudiaron los n-grams más frecuentes. Se generó una caracterización con una arquitectura de red neuronal CBOW (continuos bag of words) para la incrustación de palabras. Utilizando algoritmos de clustering se obtuvo evidencia que indica que palabras cercanas en el espacio de incrustación de 300 dimensiones pueden llegar a representar asociaciones referentes a tipos de pacientes, o agrupar palabras similares, incluyendo palabras escritas con errores ortográficos. El corpus generado y los resultados encontrados sientan las bases para trabajos futuros en la detección de entidades (síntomas, signos, diagnósticos, tratamientos), la corrección de errores ortográficos y las relaciones semánticas entre palabras para generar resúmenes de historias clínicas o asistir el seguimiento de las maternas mediante la revisión automatizada de la historia clínica electrónica(AU)


The purpose of this article was to characterize the free text available in an electronic health record of an institution, directed at the care of patients in pregnancy. More than being a data repository, the electronic health record (HCE) has become a clinical decision support system (CDSS). However, due to the high volume of information, as some of the key information in EHR is in free text form, using the full potential that EHR information offers to improve clinical decision-making requires the support of methods of text mining and natural language processing (PLN). Particularly in the area of gynecology and obstetrics, the implementation of PLN methods could help speed up the identification of factors associated with maternal risk. Despite this, in the literature there are no papers that integrate PLN techniques in EHR associated with maternal follow-up in Spanish. Taking into account this knowledge gap, in this work a corpus was generated and characterized from the EHRs of a gynecology and obstetrics service characterized by treating high-risk maternal patients. PLN and text mining methods were implemented on the data, obtaining 659 789 tokens and a dictionary with unique words given by 7 334 tokens. The characterization of the data was developed from the identification of the most frequent words and n-grams and a vector representation of embedding words in a 300-dimensional space was performed using a CBOW (Continuous Bag of Words) neural network architecture. The embedding of words allowed to verify by means of Clustering algorithms, that the words associated to the same group can come to represent associations referring to types of patients, or group similar words, including words written with spelling errors. The corpus generated and the results found lay the foundations for future work in the detection of entities (symptoms, signs, diagnoses, treatments), correction of spelling errors and semantic relationships between words to generate summaries of medical records or assist the follow-up of mothers through the automated review of the electronic health record(AU)


Subject(s)
Humans , Female , Pregnancy , Natural Language Processing , Electronic Health Records
4.
Arch. cardiol. Méx ; 91(1): 58-65, ene.-mar. 2021. tab, graf
Article in English | LILACS | ID: biblio-1152861

ABSTRACT

Abstract Objective: The aim of this study was to develop, train, and test different neural network (NN) algorithm-based models to improve the Global Registry of Acute Coronary Events (GRACE) score performance to predict in-hospital mortality after an acute coronary syndrome. Methods: We analyzed a prospective database, including 40 admission variables of 1255 patients admitted with the acute coronary syndrome in a community hospital. Individual predictors included in GRACE score were used to train and test three NN algorithm-based models (guided models), namely: one- and two-hidden layer multilayer perceptron and a radial basis function network. Three extra NNs were built using the 40 admission variables of the entire database (unguided models). Expected mortality according to GRACE score was calculated using the logistic regression equation. Results: In terms of receiver operating characteristic area and negative predictive value (NPV), almost all NN algorithms outperformed logistic regression. Only radial basis function models obtained a better accuracy level based on NPV improvement, at the expense of positive predictive value (PPV) reduction. The independent normalized importance of variables for the best unguided NN was: creatinine 100%, Killip class 61%, ejection fraction 52%, age 44%, maximum creatine-kinase level 41%, glycemia 40%, left bundle branch block 35%, and weight 33%, among the top 8 predictors. Conclusions: Treatment of individual predictors of GRACE score with NN algorithms improved accuracy and discrimination power in all models with respect to the traditional logistic regression approach; nevertheless, PPV was only marginally enhanced. Unguided variable selection would be able to achieve better results in PPV terms.


Resumen Objetivo: El objetivo fue desarrollar, entrenar y probar diferentes modelos basados en algoritmos de redes neuronales (RN) para mejorar el rendimiento del score del Registro Global de Eventos Coronarios Agudos (GRACE) para predecir la mortalidad hospitalaria después de un síndrome coronario agudo. Métodos: Analizamos una base de datos prospectiva que incluía 40 variables de ingreso de 1255 pacientes con síndrome coronario agudo en un hospital comunitario. Las variables incluidas en la puntuación GRACE se usaron para entrenar y probar tres algoritmos basados en RN (modelos guiados), a saber: perceptrones multicapa de una y dos capas ocultas y una red de función de base radial. Se construyeron tres RN adicionales utilizando las 40 variables de admisión de toda la base de datos (modelos no guiados). La mortalidad esperada según el GRACE se calculó usando la ecuación de regresión logística. Resultados: En términos del área ROC y valor predictivo negativo (VPN), casi todos los algoritmos RN superaron la regresión logística. Solo los modelos de función de base radial obtuvieron un mejor nivel de precisión basado en la mejora del VPN, pero a expensas de la reducción del valor predictivo positivo (VPP). La importancia normalizada de las variables incluidas en la mejor RN no guiada fue: creatinina 100%, clase Killip 61%, fracción de eyección 52%, edad 44%, nivel máximo de creatina quinasa 41%, glucemia 40%, bloqueo de rama izquierda 35%, y peso 33%, entre los 8 predictores principales. Conclusiones: El tratamiento de las variables del score GRACE mediante algoritmos de RN mejoró la precisión y la discriminación en todos los modelos con respecto al enfoque tradicional de regresión logística; sin embargo, el VPP solo mejoró marginalmente. La selección no guiada de variables podría mejorar los resultados en términos de PPV.


Subject(s)
Humans , Male , Female , Middle Aged , Aged , Algorithms , Registries , Neural Networks, Computer , Hospital Mortality , Acute Coronary Syndrome/mortality , Prognosis , Databases, Factual
5.
Braz. J. Pharm. Sci. (Online) ; 56: e17808, 2020. tab, graf
Article in English | LILACS | ID: biblio-1089231

ABSTRACT

This study evaluated the incorporation of tetracaine into liposomes by RSM (Response Surface Methodology) and ANN (Artificial Neural Networks) based models. RCCD (rotational central composite design) and ANN were performed to optimize the sonication conditions of particles containing 100 % lipid. Laser light scattering was used to perform measure hydrodynamic radius and size distribution of vesicles. The liposomal formulations were analyzed by incorporating the drug into the hydrophilic phase or the lipophilic phase. RCCD and ANN were conducted, having the lipid/cholesterol ratio and concentration of tetracaine as variables investigated and, the encapsulation efficiency and mean diameter of the vesicles as response variables. The optimum sonication condition set at a power of 16 kHz and 3 minutes, resulting in sizes smaller than 800 nm. Maximum encapsulation efficiency (39.7 %) was obtained in the hydrophilic phase to a tetracaine concentration of 8.37 mg/mL and 79.5:20.5% lipid/cholesterol ratio. Liposomes were stable for about 30 days (at 4 ºC), and the drug encapsulation efficiency was higher in the hydrophilic phase. The experimental results of RCCD-RSM and ANN techniques show ANN obtained more refined prediction errors that RCCD-RSM technique, therefore, ANN can be considered as an efficient mathematical method to characterize the incorporation of tetracaine into liposomes.


Subject(s)
Tetracaine/analysis , Liposomes/metabolism , Pharmaceutical Preparations/analysis , Efficiency/classification , Methodology as a Subject
6.
Rev. Psicol. Saúde ; 11(2): 171-183, maio-ago. 2019. ilus
Article in English | LILACS-Express | LILACS | ID: biblio-1020436

ABSTRACT

The focus of modern neuroscience on cognitive processes has relegated to behavior the epiphenomenal status of neural processing and the difficulties generated by this interpretation have encouraged the use of computational models. However, the implementation based on inferred cognitive constructs has been inefficient. The objective of this work was to review the concept of behavior by a selectionist approach and propose a connectionist computational model that operates integrally with its neurophysiological bases. The behavioral phenomenon was functionally defined and described at different levels of analysis. Functional levels make it possible to understand why behavioral phenomena exist, while topographic levels describe how morphophysiological mechanisms implement the response. The connectionist notions of PDP ANNs formalizes the proposal. The model stands out for contextualizing neural processing as part of the response, addressing the behavioral phenomenon as a whole that needs to be explained in its most different levels of analysis.


O enfoque das neurociências modernas nos processos cognitivos tem relegado ao comportamento o status de epifenômeno do processamento neural e as dificuldades geradas por essa interpretação incentivaram o uso de modelos computacionais. Entretanto, a implementação pautada em construtos cognitivos inferidos tem sido ineficiente. Foi objetivo desse trabalho revisar o conceito de comportamento pelo viés selecionista para se propor um modelo computacional conexionista que opere integradamente com suas bases neurofisiológicas. O fenômeno comportamental foi definido funcionalmente e descrito em diferentes níveis de análise. Os níveis funcionais possibilitam entender o porquê do fenômeno comportamental, enquanto que os níveis topográficos descrevem como os mecanismos morfofisiológicos implementam a resposta. A formalização do modelo foi realizada com noções conexionistas de RNAs de PDP. O modelo se destaca por contextualizar o processamento neural como parte da resposta, tratando o fenômeno comportamental como um todo que precisa ser explicado em seus mais diferentes níveis de análise.


El enfoque de las neurociencias modernas en los procesos ha relegado al comportamiento el status de epifenómeno del procesamiento neural y las dificultades generadas por esa interpretación incentivaron el uso de modelos computacionales. Sin embargo, la implementación pautada en construcciones cognoscitivas inferidas ha sido ineficiente. Fue objetivo de ese trabajo revisar el concepto de conducta por el sesgo seleccionista para proponer un modelo computacional conexionista que opere íntegramente con sus bases neurofisiológicas. El fenómeno conductual fue definió funcionalmente y descrito en diferentes niveles de análisis. Los niveles funcionales posibilitan entender el porqué del fenómeno conductual, mientras que los niveles topográficos describen cómo los mecanismos morfofisiológicos implementan la respuesta. La formalización del modelo fue realizada con nociones conectivistas de RNAs de PDP. El modelo se destaca por contextualizar el procesamiento neural como parte de la respuesta, tratando el fenómeno conductual como un todo que necesita ser explicado en sus más diferentes niveles de análisis.

7.
Article | IMSEAR | ID: sea-203627

ABSTRACT

Background: Various indices derived from red blood cell (RBC) parameters have been described for distinguishing betathalassemia minor and other types of hypochromic microcytic anemia. Objective: The study is aimed at investigating thediagnostic reliability of different RBC indices and formulas in differentiation between beta thalassemia minor and othertypes of hypochromic microcytic anemia. Subjects and Methods: This is a cross‐sectional study which was carried out sincefirst of Jan 2011 to end of December 2011 on 171 children with hypochromic microcytic anemia in Kut Oncology Centre,Wasit, Iraq. Results: There was a statistical significant difference between thalassemic group and other groups regardingblood indices as well as the eight formulas which were used. The highest correctly identified patients (PCIP) was reportedfor RBCs count (84%) with sensitivity and specificity of 96.3%. The Youden's index for RBCs was 58.2 which is the highestvalue compared with other seven parameters or indices which were used in this study. The second highest Youden's indexwas for G & K index, with 78.4% PCIP, and sensitivity and specificity of 98.2%. Youden's index of red cell distributionwidth (RDW) was the lowest value compared to other values used in this study as well as the lowest percentage of correctlyidentified patients (65%). The sensitivity and specificity of RDW for BTM was 86.1%. Conclusion: According to this study,cell counter-based parameters and formulas, particularly RBCs, and Green and King index are superior to all othermethods examined for distinguishing between thalassemia trait and other hypochromic microcytic anemia; while, RDW wasinadequate and ineffective for that purpose.

8.
Acta Pharmaceutica Sinica B ; (6): 177-185, 2019.
Article in English | WPRIM | ID: wpr-774992

ABSTRACT

Current pharmaceutical formulation development still strongly relies on the traditional trial-and-error methods of pharmaceutical scientists. This approach is laborious, time-consuming and costly. Recently, deep learning has been widely applied in many challenging domains because of its important capability of automatic feature extraction. The aim of the present research is to apply deep learning methods to predict pharmaceutical formulations. In this paper, two types of dosage forms were chosen as model systems. Evaluation criteria suitable for pharmaceutics were applied to assess the performance of the models. Moreover, an automatic dataset selection algorithm was developed for selecting the representative data as validation and test datasets. Six machine learning methods were compared with deep learning. Results showed that the accuracies of both two deep neural networks were above 80% and higher than other machine learning models; the latter showed good prediction of pharmaceutical formulations. In summary, deep learning employing an automatic data splitting algorithm and the evaluation criteria suitable for pharmaceutical formulation data was developed for the prediction of pharmaceutical formulations for the first time. The cross-disciplinary integration of pharmaceutics and artificial intelligence may shift the paradigm of pharmaceutical research from experience-dependent studies to data-driven methodologies.

9.
Chinese Journal of Lung Cancer ; (12): 245-249, 2019.
Article in Chinese | WPRIM | ID: wpr-775636

ABSTRACT

Lung cancer is the most common and fatal tumor in the world with limited diagnostic and treatment methods. The development of precision medicine has brought new opportunities for the improvement of diagnosis and treatment of lung cancer. However, various kinds of information required by precision medicine (such as biometrics, clinical test indicators and non-biological environmental background information) are difficult for clinicians to integrate and utilize effectively. With the development of computer technology, artificial neural networks (ANNs), which has the characteristic of high fault tolerance, intelligence and self-learning ability. Its powerful information integration ability can solve many problems in the development and application of precision medicine, which can play a key role in basic research and clinical practice associated with lung cancer. This article reviewed the application of artificial neural network in the field of lung cancer.
.


Subject(s)
Humans , Biomedical Research , Methods , Lung Neoplasms , Diagnostic Imaging , Therapeutics , Neural Networks, Computer
10.
Res. Biomed. Eng. (Online) ; 34(1): 45-53, Jan.-Mar. 2018. tab, graf
Article in English | LILACS | ID: biblio-896209

ABSTRACT

Abstract Introduction Breast cancer is the most common cancer in women and one of the major causes of death from cancer among female around the world. The early detection and treatment are the major way to healing. The use of mammary thermography in Mastology is increasing as a complementary imaging technique to early detect lesions. Its use as a screening exam to identify breast disorders has been investigated. The aim of this study is to investigate the behavior of different classification methods while grouping the thermographic images into specific types of lesions. Methods To evaluate our proposal, we built classifiers based on artificial neural networks, decision trees, Bayesian classifiers, and Haralick and Zernike attributes. The image database is composed by thermographic images acquired at the University Hospital of the Federal University of Pernambuco. These images are clinically classified into the classes cyst, malignant and benign. Moments of Zernike and Haralick were used as attributes. Results Extreme Learning Machines (ELM) and Multilayer Perceptron networks (MLP) proved to be quite efficient classifiers for classification of breast lesions in thermographic images. Using 75% of the database for training, the maximum value obtained for accuracy was 73.38%, with a Kappa index of 0.6007. This result indicated to a sensitivity of 78% and specificity of 88%. The overall efficiency of the system was 83%. Conclusion ELM showed to be a promising classifier to be used in the differentiation of breast lesions in thermographic images, due to its low computational cost and robustness.

11.
Braz. arch. biol. technol ; 61(spe): e18000180, 2018. tab, graf
Article in English | LILACS | ID: biblio-974154

ABSTRACT

ABSTRACT This work presents the methodology, development and testing of an autonomous system, based on Artificial Neural Networks (ANN), for the reduction of technical losses in reticulated underground systems through the optimal control of the capacitor banks (CBs) present in the grid. The proposed methodology includes Smart Grid features, including practical solutions for current transformers positioning in underground networks, collecting field measurements for the Distribution Operation Centre (DOC) and real-time control of field equipment (capacitors banks). The steps of the proposed methodology and the main aspects of the development of the system are also described, as well as the tests performed to prove the results and validate the system.


Subject(s)
Neural Networks, Computer , Electric Wiring , Energy Consumption , Sustainable Development
12.
Journal of the Korean Society of Maternal and Child Health ; : 151-161, 2018.
Article in Korean | WPRIM | ID: wpr-758545

ABSTRACT

PURPOSE: The objective of the present study was to predict the gestational age at preterm birth using artificial neural networks for singleton pregnancy. METHODS: Artificial neural networks (ANNs) were used as a tool for the prediction of gestational age at birth. ANNs trained using obstetrical data of 125 cases, including 56 preterm and 69 non-preterm deliveries. Using a 36-variable obstetrical input set, gestational weeks at delivery were predicted by 89 cases of training sets, 18 cases of validating sets, and 18 cases of testing sets (total: 125 cases). After training, we validated the model by another 12 cases containing data of preterm deliveries. RESULTS: To define the accuracy of the developed model, we confirmed the correlation coefficient (R) and mean square error of the model. For validating sets, the correlation coefficient was 0.839, but R of testing sets was 0.892, and R of total 125 cases was 0.959. The neural networks were well trained, and the model predictions were relatively good. Furthermore, the model was validated with another dataset of 12 cases, and the correlation coefficient was 0.709. The error days were 11.58±13.73. CONCLUSION: In the present study, we trained the ANNs and developed the predictive model for gestational age at delivery. Although the prediction for gestational age at birth in singleton preterm birth was feasible, further studies with larger data, including detailed risk variables of preterm birth and other obstetrical outcomes, are needed.


Subject(s)
Pregnancy , Dataset , Gestational Age , Parturition , Premature Birth
13.
Orinoquia ; 21(supl.1): 11-19, jul.-dic. 2017. graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1091535

ABSTRACT

Resumen La metodología de clustering fue utilizada para agrupar tres barrios en Quibdó teniendo en cuenta factores que favorecen el desarrollo de la malaria. Los mapas auto-organizados de Kohonen fueron utilizados para el análisis de las características más significativas en la clasificación. Los clusters detectados fueron comparados con la clasificación geográfica de las casas, encontrando, que los mapas auto-organizados de Kohonen clasifican las casas por las condiciones ambientales propicias para el desarrollo del mosquito más que por la clasificación administrativa de la ciudad.


Resumo A Metodologia de Clustering foi usada para agrupar três bairros em Quibdo, Colômbia, levando em consideração fatores que favorecem o desenvolvimento da malária. Mapas auto-organizados de Kohonen foram utilizados para a análise das características mais significativas no agrupamento. Os Clusters detectados foram comparados com o agrupamento geo-gráfico de casas, mostrando que os mapas auto-organizados de Kohonen agrupam as casas pelas condições ambientais favoráveis ao desenvolvimento do mosquito e não pelo agrupamento administrativo da cidade.


Abstract Clustering methodology was used to group three neighborhoods in Quibdo taking into account factors that favor the development of malaria. The Kohonen self-organizing maps were used for the analysis of the most significant features in the standings. The detected clusters were compared with the geographical classification of houses, finding that the Kohonen self-organizing maps households classified by environmental conditions conducive to development rather than the administrative classification of the city.

14.
Res. Biomed. Eng. (Online) ; 33(2): 121-129, Apr.-June 2017. tab, graf
Article in English | LILACS | ID: biblio-896181

ABSTRACT

Abstract Introduction: One of the most recurrent pathologies in the spine is scoliosis. It occurs in the frontal plane and is formed by one or more curves in the spinal column. The scoliosis causes global postural misalignment in an individual. One of the modifications produced by postural misalignment is the way in which an individual distributes weight to the feet. We aimed to implement an electronic system for separating patients with Degree I scoliosis (i.e., 1° to 19° scoliosis according to the Ricard classification) into two groups: C1 (1°-9°) and C2 (10°-9°). The highest percentage of patients with scoliosis is in this range: those who do not need to wear vests or undergo surgery and whose treatment is performed via special physical exercise and frequent evaluations by healthcare professionals. Methods The electronic system consists of a baropodometer and artificial neural networks (ANNs). The classification of patients in the scoliosis groups was performed with MATLAB software and a Single Layer Perceptron network using the backpropagation training algorithm. Evaluations were performed on 63 volunteers. Results The mean classification sensitivity was 93.7% in the C1 group and 94.5% in the C2 group. The classification accuracy was 83.3% in the C1 group and 96.0% in the C2 group. Conclusion The implemented system can contribute to the treatment of patients with scoliosis grades ranging from 1° to 19°, which represents the highest incidence of this pathology, for which the monitoring of the clinical condition using noninvasive techniques is of fundamental importance.

15.
Rev. mex. ing. bioméd ; 38(1): 208-216, ene.-abr. 2017. tab, graf
Article in Spanish | LILACS | ID: biblio-902338

ABSTRACT

Resumen: Las redes neuronales artificiales (RNA) son un método computacional extensamente utilizado para resolver problemas complejos y realizar predicciones en sistemas de relación no lineal. En este trabajo se utilizaron RNA para predecir la respuesta fisiológica obtenida al adicionar una concentración específica de digoxina a corazones de Tivela stultorum, un organismo modelo para probar fármacos cardíacos que se pretenden utilizar en humanos. Las entradas de la RNA fueron el peso, volumen, largo y ancho del corazón, la concentración de digoxina, el volumen utilizado para la dilución de digoxina, el máximo y mínimo de contracción, tiempo de llenado, y frecuencia cardíaca antes de adicionar la digoxina, las salidas fueron el máximo y mínimo de contracción, tiempo de llenado y frecuencia cardíaca esperados después de agregar digoxina al corazón. Las RNA se entrenaron, validaron y probaron con los resultados de experimentos in vivo. Para elegir la red óptima se utilizó el valor más pequeño del error medio cuadrado. Se obtuvo una correlación alta entre los valores predichos y calculados, excepto en el caso del tiempo de llenado. Se lograron obtener predicciones acertadas de la cardioactividad de la almeja T. stultorum cuando se les agrega una concentración específica de digoxina haciendo uso de RNA; esto con el fin de utilizarse como una herramienta para facilitar las pruebas en el laboratorio de los efectos de la digoxina.


Abstract: Artificial neural networks (ANN) are a computational method that has been widely used to solve complex problems and carry out predictions on nonlinear systems. Multilayer perceptron artificial neural networks were used to predict the physiological response that would be obtained by adding a specific concentration of digoxin to Tivela stultorum hearts, this organism is a model for testing cardiac drugs that pretends to be used in humans. The MLP-ANN inputs were weight, volume, length, and width of the heart, digoxin concentration and volume used for diluting digoxin, and maximum contraction, minimum contraction, filling time, and heart rate before adding digoxin, and the outputs were the maximum contraction, minimum contraction, filling time, and heart rate that would be obtained after adding digoxin to the heart. ANNs were trained, validated, and tested with the results obtained from the in vivo experiments. To choose the optimal network, the smallest square mean error value was used. Perceptrons obtained a high performance and correlation between predicted and calculated values, except in the case of the filling time output. Accurate predictions of the T. stultorum clams cardioactivity were obtained when a specific concentration of digoxin was added using ANNs with one hidden layer; this could be useful as a tool to facilitate laboratory experiments to test digoxin effects.

16.
Res. Biomed. Eng. (Online) ; 33(1): 69-77, Mar. 2017. tab, graf
Article in English | LILACS | ID: biblio-842483

ABSTRACT

Abstract Introduction Breast cancer is the first leading cause of death for women in Brazil as well as in most countries in the world. Due to the relation between the breast density and the risk of breast cancer, in medical practice, the breast density classification is merely visual and dependent on professional experience, making this task very subjective. The purpose of this paper is to investigate image features based on histograms and Haralick texture descriptors so as to separate mammographic images into categories of breast density using an Artificial Neural Network. Methods We used 307 mammographic images from the INbreast digital database, extracting histogram features and texture descriptors of all mammograms and selecting them with the K-means technique. Then, these groups of selected features were used as inputs of an Artificial Neural Network to classify the images automatically into the four categories reported by radiologists. Results An average accuracy of 92.9% was obtained in a few tests using only some of the Haralick texture descriptors. Also, the accuracy rate increased to 98.95% when texture descriptors were mixed with some features based on a histogram. Conclusion Texture descriptors have proven to be better than gray levels features at differentiating the breast densities in mammographic images. From this paper, it was possible to automate the feature selection and the classification with acceptable error rates since the extraction of the features is suitable to the characteristics of the images involving the problem.

17.
China Medical Equipment ; (12): 142-145, 2017.
Article in Chinese | WPRIM | ID: wpr-664412

ABSTRACT

To analyze the application and research direction of artificial intelligence in the diagnosis field of diabetes through summarized the methods and principle of artificial intelligence, artificial neural network, expert system and data mining. The diagnosis of diabetes need be supported by large medical resource. The artificial intelligence is applied in the diagnosis of diabetes not only can save medical resource but also can help patients with diabetes and high risk group of diabetes to grasp their state of illness in time, and reduce the sickening risk of diabetic complication.

18.
Pesqui. vet. bras ; 36(7): 652-656, jul. 2016. tab, graf, ilus
Article in English | LILACS, VETINDEX | ID: lil-794775

ABSTRACT

The thymus is a lymphoid organ and usually evaluated for the degree of lymphocyte loss with subjective histological techniques. This study aimed to adapt and to apply of the digital analysis of the lymphoid depletion system (ADDL) in the thymus in order to obtain a more accurate analysis. Glucocorticoid was used to induce immunosuppression in 55 broilers at 21 days of age; other 15 broilers were the control group. After euthanasia of the broilers, postmortem examination was made. Both thymic chains were collected and six lobes were selected for histological examination of the degree of lymphocyte depletion (scores 1 to 5) and for submission to all stages of processing by the ADDL system. The artificial constructed neural networks (ANN) obtained 94.03% of correct classifications. In conclusion, it was possible to adopt objective criteria to evaluate thymic lymphoid depletion with the ADDL system.(AU)


O timo é um órgão linfóide, que é normalmente avaliado para o grau de perda de linfócitos a partir de técnicas histológicas subjetivas. Este trabalho teve como objetivo a adaptação e aplicação do sistema de análise digital de depleção linfóide (ADDL) para o timo, a fim de tornar sua análise mais acurada. Glicocorticóides foram utilizados a fim de induzir imunossupressão em 55 aves de 21 dias de idade. Outras 15 aves formaram o grupo controle. Posteriormente, para cada um dos aves, realizou-se a eutanásia e necropsia. Ambas as cadeias do timo foram coletadas e foram selecionadas seis lóbulos para processamento histológico, análise quanto ao grau de depleção linfocitária (escores de 1-5) e submissão a todas as fases do processamento pelo sistema ADDL. Observou-se que a rede neural artificial (RNA) construída obteve 94,03% de classificações corretas. Em conclusão, foi possível adotar critérios objetivos para avaliar a depleção linfóide tímica utilizando o sistema ADDL.(AU)


Subject(s)
Animals , Chickens/physiology , Immunity, Cellular/physiology , Lymphocyte Depletion/veterinary , Lymphocytes/physiology , Nerve Net/physiology , Thymus Gland/physiopathology , Glucocorticoids/analysis
19.
Chinese Pharmaceutical Journal ; (24): 904-909, 2016.
Article in Chinese | WPRIM | ID: wpr-859093

ABSTRACT

OBJECTIVE: To establish a method for predicting tablet hardness by near infrared diffuse reflection spectroscopy. METHODS: Tablet hardness value was obtained by hardness meter. Calibration model between NIR spectra and the hardness was establish by partial least squares regression (PLSR) method and BP-ANN method. RESULTS: Correlation coefficients (r), root mean squares error of cross-validation (RMSECV), and root mean square error of prediction (RMSEP) obtained by PLSR model were 0.977 8, 0.742 and 0.815 kg respectively. And the correlation coefficients of training set, monitor set and testing set by BP-ANN were 0.987 3, 0.985 6, and 0.986 8, with RSE% of 6.83%, 8.77%, and 6.69%, respectively. CONCLUSION: The prediction accuracy of BP-ANN nonlinear model is superior to the PLSR model.

20.
Chinese Traditional and Herbal Drugs ; (24): 4282-4288, 2016.
Article in Chinese | WPRIM | ID: wpr-853140

ABSTRACT

In recent years, with the development of Chinese materia medica (CMM) industry, the problem of quality control method is not comprehensive. It becomes the most important factor to block the development of CMM. Many scholars look for some new methods, by which the quality of CMM could be assessed objectively and accurately. Since 1980s, the pattern recognition was introduced to the chemical field and was applied to CMM at the same time. And there were some CMM quality assessment methods based on the pattern recognition established so far. In this article, the latest research progress in the pattern recognition, basic principle, and technology, was introduced and the applications in principal component analysis, cluster analysis, discriminant analysis, grey correlation analysis, partial least squares, heuristic evolving latent projections and artificial neural networks of CMM quality assessment have been reviewed, so as to provide the reference for further studies and application in CMM.

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