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1.
Sci Rep ; 12(1): 1123, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-35064165

RESUMO

Accurate and early detection of anomalies in peripheral white blood cells plays a crucial role in the evaluation of well-being in individuals and the diagnosis and prognosis of hematologic diseases. For example, some blood disorders and immune system-related diseases are diagnosed by the differential count of white blood cells, which is one of the common laboratory tests. Data is one of the most important ingredients in the development and testing of many commercial and successful automatic or semi-automatic systems. To this end, this study introduces a free access dataset of normal peripheral white blood cells called Raabin-WBC containing about 40,000 images of white blood cells and color spots. For ensuring the validity of the data, a significant number of cells were labeled by two experts. Also, the ground truths of the nuclei and cytoplasm are extracted for 1145 selected cells. To provide the necessary diversity, various smears have been imaged, and two different cameras and two different microscopes were used. We did some preliminary deep learning experiments on Raabin-WBC to demonstrate how the generalization power of machine learning methods, especially deep neural networks, can be affected by the mentioned diversity. Raabin-WBC as a public data in the field of health can be used for the model development and testing in different machine learning tasks including classification, detection, segmentation, and localization.


Assuntos
Aprendizado Profundo , Doenças Hematológicas/diagnóstico , Leucócitos/citologia , Adolescente , Adulto , Idoso , Núcleo Celular , Criança , Citoplasma , Conjuntos de Dados como Assunto , Partículas Elementares , Feminino , Doenças Hematológicas/sangue , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
2.
Sci Rep ; 11(1): 19428, 2021 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-34593873

RESUMO

This article addresses a new method for the classification of white blood cells (WBCs) using image processing techniques and machine learning methods. The proposed method consists of three steps: detecting the nucleus and cytoplasm, extracting features, and classification. At first, a new algorithm is designed to segment the nucleus. For the cytoplasm to be detected, only a part of it located inside the convex hull of the nucleus is involved in the process. This attitude helps us overcome the difficulties of segmenting the cytoplasm. In the second phase, three shapes and four novel color features are devised and extracted. Finally, by using an SVM model, the WBCs are classified. The segmentation algorithm can detect the nucleus with a dice similarity coefficient of 0.9675. The proposed method can categorize WBCs in Raabin-WBC, LISC, and BCCD datasets with accuracies of 94.65%, 92.21%, and 94.20%, respectively. Besides, we show that the proposed method possesses more generalization power than pre-trained CNN models. It is worth mentioning that the hyperparameters of the classifier are fixed only with the Raabin-WBC dataset, and these parameters are not readjusted for LISC and BCCD datasets.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Leucócitos/ultraestrutura , Aprendizado de Máquina , Humanos , Contagem de Leucócitos , Leucócitos/citologia
3.
PLoS One ; 15(12): e0241690, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33301502

RESUMO

The increase in the number of children with autism and the importance of early autism intervention has prompted researchers to perform automatic and early autism screening. Consequently, in the present paper, a cry-based screening approach for children with Autism Spectrum Disorder (ASD) is introduced which would provide both early and automatic screening. During the study, we realized that ASD specific features are not necessarily observable in all children with ASD and in all instances collected from each child. Therefore, we proposed a new classification approach to be able to determine such features and their corresponding instances. To test the proposed approach a set of data relating to children between 18 to 53 months which had been recorded using high-quality voice recording devices and typical smartphones at various locations such as homes and daycares was studied. Then, after preprocessing, the approach was used to train a classifier, using data for 10 boys with ASD and 10 Typically Developed (TD) boys. The trained classifier was tested on the data of 14 boys and 7 girls with ASD and 14 TD boys and 7 TD girls. The sensitivity, specificity, and precision of the proposed approach for boys were 85.71%, 100%, and 92.85%, respectively. These measures were 71.42%, 100%, and 85.71% for girls, respectively. It was shown that the proposed approach outperforms the common classification methods. Furthermore, it demonstrated better results than the studies which used voice features for screening ASD. To pilot the practicality of the proposed approach for early autism screening, the trained classifier was tested on 57 participants between 10 to 18 months. These 57 participants consisted of 28 boys and 29 girls and the results were very encouraging for the use of the approach in early ASD screening.


Assuntos
Transtorno do Espectro Autista/diagnóstico , Choro/fisiologia , Diagnóstico por Computador/métodos , Diagnóstico Precoce , Programas de Rastreamento/métodos , Transtorno do Espectro Autista/fisiopatologia , Pré-Escolar , Diagnóstico por Computador/instrumentação , Feminino , Seguimentos , Humanos , Lactente , Masculino , Programas de Rastreamento/instrumentação , Projetos Piloto , Sensibilidade e Especificidade , Smartphone , Interface para o Reconhecimento da Fala
4.
IEEE Trans Neural Netw Learn Syst ; 30(6): 1635-1650, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30307878

RESUMO

Due to the lack of enough generalization in the state space, common methods of reinforcement learning suffer from slow learning speed, especially in the early learning trials. This paper introduces a model-based method in discrete state spaces for increasing the learning speed in terms of required experiences (but not required computation time) by exploiting generalization in the experiences of the subspaces. A subspace is formed by choosing a subset of features in the original state representation. Generalization and faster learning in a subspace are due to many-to-one mapping of experiences from the state space to each state in the subspace. Nevertheless, due to inherent perceptual aliasing (PA) in the subspaces, the policy suggested by each subspace does not generally converge to the optimal policy. Our approach, called model-based learning with subspaces (MoBLeSs), calculates the confidence intervals of the estimated Q -values in the state space and in the subspaces. These confidence intervals are used in the decision-making, such that the agent benefits the most from the possible generalization while avoiding from the detriment of the PA in the subspaces. The convergence of MoBLeS to the optimal policy is theoretically investigated. In addition, we show through several experiments that MoBLeS improves the learning speed in the early trials.

5.
PLoS One ; 7(7): e39857, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22859943

RESUMO

We present a probabilistic model for natural images that is based on mixtures of Gaussian scale mixtures and a simple multiscale representation. We show that it is able to generate images with interesting higher-order correlations when trained on natural images or samples from an occlusion-based model. More importantly, our multiscale model allows for a principled evaluation. While it is easy to generate visually appealing images, we demonstrate that our model also yields the best performance reported to date when evaluated with respect to the cross-entropy rate, a measure tightly linked to the average log-likelihood. The ability to quantitatively evaluate our model differentiates it from other multiscale models, for which evaluation of these kinds of measures is usually intractable.


Assuntos
Gráficos por Computador , Modelos Estatísticos , Algoritmos , Simulação por Computador , Processamento de Imagem Assistida por Computador , Funções Verossimilhança , Cadeias de Markov , Análise Multivariada , Distribuição Normal , Software
6.
Vision Res ; 50(22): 2213-22, 2010 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-20705084

RESUMO

The light intensities of natural images exhibit a high degree of redundancy. Knowing the exact amount of their statistical dependencies is important for biological vision as well as compression and coding applications but estimating the total amount of redundancy, the multi-information, is intrinsically hard. The common approach is to estimate the multi-information for patches of increasing sizes and divide by the number of pixels. Here, we show that the limiting value of this sequence--the multi-information rate--can be better estimated by using another limiting process based on measuring the mutual information between a pixel and a causal neighborhood of increasing size around it. Although in principle this method has been known for decades, its superiority for estimating the multi-information rate of natural images has not been fully exploited yet. Either method provides a lower bound on the multi-information rate, but the mutual information based sequence converges much faster to the multi-information rate than the conventional method does. Using this fact, we provide improved estimates of the multi-information rate of natural images and a better understanding of its underlying spatial structure.


Assuntos
Modelos Biológicos , Percepção Visual/fisiologia , Algoritmos , Humanos , Iluminação , Córtex Visual/fisiologia
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