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1.
Environ Res ; 250: 118530, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38387491

RESUMO

A novel multimode colorimetric and fluorescent chemosensor was developed using an 8-hydroxy quinoline carbaldehyde Schiff base with a quinoline hydrazide probe (E)-2-((2-(quinolin-2-yl)hydrazineylidene)methyl)quinolin-8-ol (L). NMR (1H & 13C), FTIR, and HR-mass spectral characterization techniques confirmed the probe L structural conformation. As Probe L contacts Pb2+ ions, a color change and turn-off emission can be visually detected in EtOH:H2O (1:1, v/v, pH = 7.21) medium. The probe displays a good emission at 440 nm due to the combined ESIPT and ICT process. The Pb2+ ion interacts with the probe and selectively quenches fluorescence by inhibiting ESIPT and >CN- isomerization. As per Job's plot, L-Pb2+ complex formation occurred in a 1:1 stoichiometric ratio, with association constant (Ka) and quenching constant (Ksv) estimated at 1.52 × 105 M-1 and 4.12 × 105 M, respectively. The detection limits of Pb2+ by spectrophotometric and spectrofluorometric were 1.99 µM (41 ppb) and 23.4 nM (485 ppt), respectively. Additionally, the test paper kit and RGB tool were used to monitor the color changes of L with Pb2+ and the LOD was found to be 5.99 µM (125 ppb). Its recognition mechanism has been verified by 1H NMR, ESI-mass, and theoretical studies.


Assuntos
Colorimetria , Corantes Fluorescentes , Chumbo , Quinolinas , Bases de Schiff , Chumbo/análise , Chumbo/química , Bases de Schiff/química , Quinolinas/química , Quinolinas/análise , Corantes Fluorescentes/química , Colorimetria/métodos , Smartphone , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Espectrometria de Fluorescência/métodos
2.
Front Oncol ; 12: 834028, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35769710

RESUMO

Breast cancer is the most menacing cancer among all types of cancer in women around the globe. Early diagnosis is the only way to increase the treatment options which then decreases the death rate and increases the chance of survival in patients. However, it is a challenging task to differentiate abnormal breast tissues from normal tissues because of their structure and unclear boundaries. Therefore, early and accurate diagnosis and classification of breast lesions into malignant or benign lesions is an active domain of research. Over the decade, numerous artificial neural network (ANN)-based techniques were adopted in order to diagnose and classify breast cancer due to the unique characteristics of learning key features from complex data via a training process. However, these schemes have limitations like slow convergence and longer training time. To address the above mentioned issues, this paper employs a meta-heuristic algorithm for tuning the parameters of the neural network. The main novelty of this work is the computer-aided diagnosis scheme for detecting abnormalities in breast ultrasound images by integrating a wavelet neural network (WNN) and the grey wolf optimization (GWO) algorithm. Here, breast ultrasound (US) images are preprocessed with a sigmoid filter followed by interference-based despeckling and then by anisotropic diffusion. The automatic segmentation algorithm is adopted to extract the region of interest, and subsequently morphological and texture features are computed. Finally, the GWO-tuned WNN is exploited to accomplish the classification task. The classification performance of the proposed scheme is validated on 346 ultrasound images. Efficiency of the proposed methodology is evaluated by computing the confusion matrix and receiver operating characteristic (ROC) curve. Numerical analysis revealed that the proposed work can yield higher classification accuracy when compared to the prevailing methods and thereby proves its potential in effective breast tumor detection and classification. The proposed GWO-WNN method (98%) gives better accuracy than other methods like SOM-SVM (87.5), LOFA-SVM (93.62%), MBA-RF (96.85%), and BAS-BPNN (96.3%).

3.
Front Public Health ; 10: 834032, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35198526

RESUMO

Alzheimer's Disease (AD) is a progressive, neurodegenerative brain disease and is an incurable ailment. No drug exists for AD, but its progression can be delayed if the disorder is identified at its initial stage. Therefore, an early analysis of AD is of fundamental importance for patient care and efficient treatment. Neuroimaging techniques aim to assist the physician in the diagnosis of brain disorders by using images. Positron emission tomography (PET) is a kind of neuroimaging technique employed to create 3D images of the brain. Due to many PET images, researchers attempted to develop computer-aided diagnosis (CAD) to differentiate normal control from AD. Most of the earlier methods used image processing techniques for preprocessing and attributes extraction and then developed a model or classifier to classify the brain images. As a result, the retrieved features had a significant impact on the recognition rate of previous techniques. A novel and enhanced CAD system based on a convolutional neural network (CNN) is formulated to address this issue, capable of discriminating normal control from Alzheimer's disease patients. The proposed approach is evaluated using the 18FDG-PET images of 855 patients, including 635 normal control and 220 Alzheimer's disease patients from the ADNI database. The result showed that the proposed CAD system yields an accuracy of 96%, a sensitivity of 96%, and a specificity of 94%, leading to splendid performance when related to the methods already in use that are specified in the literature.


Assuntos
Doença de Alzheimer , Aprendizado Profundo , Doença de Alzheimer/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Redes Neurais de Computação , Neuroimagem/métodos
4.
Sensors (Basel) ; 21(23)2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34883794

RESUMO

The Industrial Internet of Things (IIoT) has led to the growth and expansion of various new opportunities in the new Industrial Transformation. There have been notable challenges regarding the security of data and challenges related to privacy when collecting real-time and automatic data while observing applications in the industry. This paper proposes an Federated Transfer Learning for Authentication and Privacy Preservation Using Novel Supportive Twin Delayed DDPG (S-TD3) Algorithm for IIoT. In FT-Block (Federated transfer learning blockchain), several blockchains are applied to preserve privacy and security for all types of industrial applications. Additionally, by introducing the authentication mechanism based on transfer learning, blockchains can enhance the preservation and security standards for industrial applications. Specifically, Novel Supportive Twin Delayed DDPG trains the user model to authenticate specific regions. As it is considered one of the most open and scalable interacting platforms of information, it successfully helps in the positive transfer of different kinds of data between devices in more significant and local operations of the industry. It is mainly due to a single authentication factor, and the poor adaptation to regular increases in the number of users and different requirements that make the current authentication mechanism suffer a lot in IIoT. As a result, it has been very clearly observed that the given solutions are very useful.


Assuntos
Internet das Coisas , Algoritmos , Segurança Computacional , Aprendizado de Máquina , Privacidade
5.
PeerJ Comput Sci ; 7: e755, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34805508

RESUMO

The proposed research motivates the 6G cellular networking for the Internet of Everything's (IoE) usage empowerment that is currently not compatible with 5G. For 6G, more innovative technological resources are required to be handled by Mobile Edge Computing (MEC). Although the demand for change in service from different sectors, the increase in IoE, the limitation of available computing resources of MEC, and intelligent resource solutions are getting much more significant. This research used IScaler, an effective model for intelligent service placement solutions and resource scaling. IScaler is considered to be made for MEC in Deep Reinforcement Learning (DRL). The paper has considered several requirements for making service placement decisions. The research also highlights several challenges geared by architectonics that submerge an Intelligent Scaling and Placement module.

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