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1.
Sci Rep ; 7(1): 7659, 2017 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-28794478

RESUMO

Morphological analysis is the standard method of assessing embryo quality; however, its inherent subjectivity tends to generate discrepancies among evaluators. Using genetic algorithms and artificial neural networks (ANNs), we developed a new method for embryo analysis that is more robust and reliable than standard methods. Bovine blastocysts produced in vitro were classified as grade 1 (excellent or good), 2 (fair), or 3 (poor) by three experienced embryologists according to the International Embryo Technology Society (IETS) standard. The images (n = 482) were subjected to automatic feature extraction, and the results were used as input for a supervised learning process. One part of the dataset (15%) was used for a blind test posterior to the fitting, for which the system had an accuracy of 76.4%. Interestingly, when the same embryologists evaluated a sub-sample (10%) of the dataset, there was only 54.0% agreement with the standard (mode for grades). However, when using the ANN to assess this sub-sample, there was 87.5% agreement with the modal values obtained by the evaluators. The presented methodology is covered by National Institute of Industrial Property (INPI) and World Intellectual Property Organization (WIPO) patents and is currently undergoing a commercial evaluation of its feasibility.


Assuntos
Inteligência Artificial , Automação Laboratorial , Blastocisto/citologia , Processamento de Imagem Assistida por Computador , Microscopia , Algoritmos , Animais , Automação Laboratorial/métodos , Bovinos , Transferência Embrionária , Feminino , Processamento de Imagem Assistida por Computador/métodos , Microscopia/métodos , Redes Neurais de Computação , Curva ROC
2.
Sci Data ; 4: 170192, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29257125

RESUMO

There is currently no objective, real-time and non-invasive method for evaluating the quality of mammalian embryos. In this study, we processed images of in vitro produced bovine blastocysts to obtain a deeper comprehension of the embryonic morphological aspects that are related to the standard evaluation of blastocysts. Information was extracted from 482 digital images of blastocysts. The resulting imaging data were individually evaluated by three experienced embryologists who graded their quality. To avoid evaluation bias, each image was related to the modal value of the evaluations. Automated image processing produced 36 quantitative variables for each image. The images, the modal and individual quality grades, and the variables extracted could potentially be used in the development of artificial intelligence techniques (e.g., evolutionary algorithms and artificial neural networks), multivariate modelling and the study of defined structures of the whole blastocyst.


Assuntos
Blastocisto , Animais , Bovinos , Feminino , Processamento de Imagem Assistida por Computador , Gravidez
3.
J Anim Sci Technol ; 56: 15, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26290704

RESUMO

BACKGROUND: Morphologically classifying embryos is important for numerous laboratory techniques, which range from basic methods to methods for assisted reproduction. However, the standard method currently used for classification is subjective and depends on an embryologist's prior training. Thus, our work was aimed at developing software to classify morphological quality for blastocysts based on digital images. METHODS: The developed methodology is suitable for the assistance of the embryologist on the task of analyzing blastocysts. The software uses artificial neural network techniques as a machine learning technique. These networks analyze both visual variables extracted from an image and biological features for an embryo. RESULTS: After the training process the final accuracy of the system using this method was 95%. To aid the end-users in operating this system, we developed a graphical user interface that can be used to produce a quality assessment based on a previously trained artificial neural network. CONCLUSIONS: This process has a high potential for applicability because it can be adapted to additional species with greater economic appeal (human beings and cattle). Based on an objective assessment (without personal bias from the embryologist) and with high reproducibility between samples or different clinics and laboratories, this method will facilitate such classification in the future as an alternative practice for assessing embryo morphologies.

4.
Rev. nutr ; 24(5): 735-742, Sept.-Oct. 2011.
Artigo em Português | LILACS | ID: lil-611649

RESUMO

OBJETIVO: Construir uma rede neural artificial para auxiliar os gestores de restaurantes universitários na previsão de refeições diárias. MÉTODOS: O estudo foi desenvolvido a partir do levantamento de oito variáveis que influenciam o número de refeições diárias servidas no restaurante universitário. Utiliza-se o algoritmo de treinamento Backpropagation. Os resultados por meio da rede são comparados com os da série estudada e com resultados da estimação por média aritmética simples. RESULTADOS: A rede proposta acompanha as inúmeras alterações que ocorrem no número de refeições diárias do restaurante universitário. Em 73 por cento dos dias analisados, o método das redes neurais artificiais apresenta uma taxa de acerto maior do que o método da média aritmética simples. CONCLUSÃO: A rede neural artificial mostrou-se mais adequada para a previsão do número de refeições do que a metodologia de média simples ou quando a decisão do número de refeições é feita de forma subjetiva, sem critérios científicos.


OBJECTIVE: This study aimed to build an artificial neural network to help the managers of university cafeterias to predict the number of daily meals. METHODS: This study was based on a survey of eight variables that influence the number of daily meals served by a university cafeteria. Backpropagation training algorithm was used and the results obtained by the network are compared with results of the studied series and the results estimated by simple arithmetic average. RESULTS: The proposed network follows the numerous changes that occur in the number of daily meals of the university cafeteria. In 73 percent of the analyzed days, the artificial neural networks method presented a greater success rate than the simple arithmetic average method. CONCLUSION: Artificial neural network predicted the number of meals better than the simple average method or than decisions made subjectively.


Assuntos
Alimentação Coletiva , Perda e Desperdício de Alimentos , Redes Neurais de Computação , Restaurantes , Serviços de Alimentação/organização & administração
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