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1.
Chem Commun (Camb) ; 58(97): 13491-13494, 2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36383343

RESUMEN

Reported here are two X-ray photochromic metal chalcogenide frameworks, which consist of tetrahedral clusters that are linked by transition-metal amine chelates. They have similar structures, but with different organic amine species, and they exhibit different coloration behavior. The photoinduced electron transfer from the metal chalcogenide clusters to the zinc amine chelates is a key point in accounting for their photochromism. Interestingly, a high-contrast (up to 12.4 times) enhancement of the optoelectronic response is obtained for the title compounds after they are treated by X-ray irradiation.

2.
Comput Biol Med ; 149: 106053, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36108415

RESUMEN

Epilepsy is a disorder of the brain denoted by frequent seizures. The symptoms of seizure include confusion, abnormal staring, and rapid, sudden, and uncontrollable hand movements. Epileptic seizure detection methods involve neurological exams, blood tests, neuropsychological tests, and neuroimaging modalities. Among these, neuroimaging modalities have received considerable attention from specialist physicians. One method to facilitate the accurate and fast diagnosis of epileptic seizures is to employ computer-aided diagnosis systems (CADS) based on deep learning (DL) and neuroimaging modalities. This paper has studied a comprehensive overview of DL methods employed for epileptic seizures detection and prediction using neuroimaging modalities. First, DL-based CADS for epileptic seizures detection and prediction using neuroimaging modalities are discussed. Also, descriptions of various datasets, preprocessing algorithms, and DL models which have been used for epileptic seizures detection and prediction have been included. Then, research on rehabilitation tools has been presented, which contains brain-computer interface (BCI), cloud computing, internet of things (IoT), hardware implementation of DL techniques on field-programmable gate array (FPGA), etc. In the discussion section, a comparison has been carried out between research on epileptic seizure detection and prediction. The challenges in epileptic seizures detection and prediction using neuroimaging modalities and DL models have been described. In addition, possible directions for future works in this field, specifically for solving challenges in datasets, DL, rehabilitation, and hardware models, have been proposed. The final section is dedicated to the conclusion which summarizes the significant findings of the paper.


Asunto(s)
Aprendizaje Profundo , Epilepsia , Algoritmos , Electroencefalografía/métodos , Epilepsia/diagnóstico por imagen , Humanos , Neuroimagen , Convulsiones/diagnóstico por imagen
3.
Front Neuroinform ; 15: 777977, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34899226

RESUMEN

Schizophrenia (SZ) is a mental disorder whereby due to the secretion of specific chemicals in the brain, the function of some brain regions is out of balance, leading to the lack of coordination between thoughts, actions, and emotions. This study provides various intelligent deep learning (DL)-based methods for automated SZ diagnosis via electroencephalography (EEG) signals. The obtained results are compared with those of conventional intelligent methods. To implement the proposed methods, the dataset of the Institute of Psychiatry and Neurology in Warsaw, Poland, has been used. First, EEG signals were divided into 25 s time frames and then were normalized by z-score or norm L2. In the classification step, two different approaches were considered for SZ diagnosis via EEG signals. In this step, the classification of EEG signals was first carried out by conventional machine learning methods, e.g., support vector machine, k-nearest neighbors, decision tree, naïve Bayes, random forest, extremely randomized trees, and bagging. Various proposed DL models, namely, long short-term memories (LSTMs), one-dimensional convolutional networks (1D-CNNs), and 1D-CNN-LSTMs, were used in the following. In this step, the DL models were implemented and compared with different activation functions. Among the proposed DL models, the CNN-LSTM architecture has had the best performance. In this architecture, the ReLU activation function with the z-score and L2-combined normalization was used. The proposed CNN-LSTM model has achieved an accuracy percentage of 99.25%, better than the results of most former studies in this field. It is worth mentioning that to perform all simulations, the k-fold cross-validation method with k = 5 has been used.

4.
Comput Biol Med ; 139: 104949, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34737139

RESUMEN

Accurate diagnosis of Autism Spectrum Disorder (ASD) followed by effective rehabilitation is essential for the management of this disorder. Artificial intelligence (AI) techniques can aid physicians to apply automatic diagnosis and rehabilitation procedures. AI techniques comprise traditional machine learning (ML) approaches and deep learning (DL) techniques. Conventional ML methods employ various feature extraction and classification techniques, but in DL, the process of feature extraction and classification is accomplished intelligently and integrally. DL methods for diagnosis of ASD have been focused on neuroimaging-based approaches. Neuroimaging techniques are non-invasive disease markers potentially useful for ASD diagnosis. Structural and functional neuroimaging techniques provide physicians substantial information about the structure (anatomy and structural connectivity) and function (activity and functional connectivity) of the brain. Due to the intricate structure and function of the brain, proposing optimum procedures for ASD diagnosis with neuroimaging data without exploiting powerful AI techniques like DL may be challenging. In this paper, studies conducted with the aid of DL networks to distinguish ASD are investigated. Rehabilitation tools provided for supporting ASD patients utilizing DL networks are also assessed. Finally, we will present important challenges in the automated detection and rehabilitation of ASD and propose some future works.


Asunto(s)
Trastorno del Espectro Autista , Aprendizaje Profundo , Inteligencia Artificial , Trastorno del Espectro Autista/diagnóstico por imagen , Encéfalo , Humanos , Imagen por Resonancia Magnética , Neuroimagen
5.
Dalton Trans ; 50(42): 14985-14989, 2021 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-34665191

RESUMEN

Reported here is the first chiral copper-rich open-framework chalcogenide with a quartz (qtz) topology built on distinctive [Cu5SnSe10] clusters connected by [SnSe4] bridging units. Through in situ sulfur doping, sulfurized compounds could be obtained that exhibit improved photocatalytic performance. This work expands the family of COCs with new building blocks and topologies and demonstrates the significance of chalcogen doping in COCs.

6.
Biomed Res Int ; 2018: 2362108, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29707566

RESUMEN

Breast Cancer is a serious threat and one of the largest causes of death of women throughout the world. The identification of cancer largely depends on digital biomedical photography analysis such as histopathological images by doctors and physicians. Analyzing histopathological images is a nontrivial task, and decisions from investigation of these kinds of images always require specialised knowledge. However, Computer Aided Diagnosis (CAD) techniques can help the doctor make more reliable decisions. The state-of-the-art Deep Neural Network (DNN) has been recently introduced for biomedical image analysis. Normally each image contains structural and statistical information. This paper classifies a set of biomedical breast cancer images (BreakHis dataset) using novel DNN techniques guided by structural and statistical information derived from the images. Specifically a Convolutional Neural Network (CNN), a Long-Short-Term-Memory (LSTM), and a combination of CNN and LSTM are proposed for breast cancer image classification. Softmax and Support Vector Machine (SVM) layers have been used for the decision-making stage after extracting features utilising the proposed novel DNN models. In this experiment the best Accuracy value of 91.00% is achieved on the 200x dataset, the best Precision value 96.00% is achieved on the 40x dataset, and the best F-Measure value is achieved on both the 40x and 100x datasets.


Asunto(s)
Neoplasias de la Mama , Bases de Datos Factuales , Procesamiento de Imagen Asistido por Computador/métodos , Redes Neurales de la Computación , Máquina de Vectores de Soporte , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/patología , Femenino , Humanos
7.
PLoS One ; 12(5): e0176214, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28459831

RESUMEN

In this paper, we propose a novel parallel architecture for fast hardware implementation of elliptic curve point multiplication (ECPM), which is the key operation of an elliptic curve cryptography processor. The point multiplication over binary fields is synthesized on both FPGA and ASIC technology by designing fast elliptic curve group operations in Jacobian projective coordinates. A novel combined point doubling and point addition (PDPA) architecture is proposed for group operations to achieve high speed and low hardware requirements for ECPM. It has been implemented over the binary field which is recommended by the National Institute of Standards and Technology (NIST). The proposed ECPM supports two Koblitz and random curves for the key sizes 233 and 163 bits. For group operations, a finite-field arithmetic operation, e.g. multiplication, is designed on a polynomial basis. The delay of a 233-bit point multiplication is only 3.05 and 3.56 µs, in a Xilinx Virtex-7 FPGA, for Koblitz and random curves, respectively, and 0.81 µs in an ASIC 65-nm technology, which are the fastest hardware implementation results reported in the literature to date. In addition, a 163-bit point multiplication is also implemented in FPGA and ASIC for fair comparison which takes around 0.33 and 0.46 µs, respectively. The area-time product of the proposed point multiplication is very low compared to similar designs. The performance ([Formula: see text]) and Area × Time × Energy (ATE) product of the proposed design are far better than the most significant studies found in the literature.


Asunto(s)
Algoritmos , Seguridad Computacional/instrumentación , Computadores , Estados Unidos , United States Government Agencies
8.
IEEE Trans Image Process ; 26(5): 2116-2126, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28237927

RESUMEN

A real-time image filtering technique is proposed which could result in faster implementation for fingerprint image enhancement. One major hurdle associated with fingerprint filtering techniques is the expensive nature of their hardware implementations. To circumvent this, a modified anisotropic Gaussian filter is efficiently adopted in hardware by decomposing the filter into two orthogonal Gaussians and an oriented line Gaussian. An architecture is developed for dynamically controlling the orientation of the line Gaussian filter. To further improve the performance of the filter, the input image is homogenized by a local image normalization. In the proposed structure, for a middle-range reconfigurable FPGA, both parallel compute-intensive and real-time demands were achieved. We manage to efficiently speed up the image-processing time and improve the resource utilization of the FPGA. Test results show an improved speed for its hardware architecture while maintaining reasonable enhancement benchmarks.

9.
Comput Math Methods Med ; 2017: 3781951, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29463985

RESUMEN

Breast cancer is one of the largest causes of women's death in the world today. Advance engineering of natural image classification techniques and Artificial Intelligence methods has largely been used for the breast-image classification task. The involvement of digital image classification allows the doctor and the physicians a second opinion, and it saves the doctors' and physicians' time. Despite the various publications on breast image classification, very few review papers are available which provide a detailed description of breast cancer image classification techniques, feature extraction and selection procedures, classification measuring parameterizations, and image classification findings. We have put a special emphasis on the Convolutional Neural Network (CNN) method for breast image classification. Along with the CNN method we have also described the involvement of the conventional Neural Network (NN), Logic Based classifiers such as the Random Forest (RF) algorithm, Support Vector Machines (SVM), Bayesian methods, and a few of the semisupervised and unsupervised methods which have been used for breast image classification.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Procesamiento de Imagen Asistido por Computador/métodos , Aprendizaje Automático , Algoritmos , Australia , Teorema de Bayes , Neoplasias de la Mama/mortalidad , Análisis por Conglomerados , Diagnóstico por Computador/métodos , Femenino , Humanos , Redes Neurales de la Computación , Reproducibilidad de los Resultados , Máquina de Vectores de Soporte
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