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1.
Sensors (Basel) ; 22(21)2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36366039

RESUMO

Healthcare is an important medical topic in recent years. In this study, the novelty we propose is the intelligent healthcare system using an inequality-type optimization mathematical model with signal-to-noise ratio (SNR) and wavelet-domain low-frequency amplitude adjustment techniques to hide patients' confidential data in their electrocardiogram (ECG) signals. The extraction of the hidden patient information also utilizes the low-frequency amplitude adjustment. The detailed steps of establishing the system are as follows. To integrate confidential patient data into ECG signals, we first propose a nonlinear model to optimize the quality of ECG signals with the embedded patients' confidential data including patient name, patient birthdate, date of medical treatment, and medical history. Then, we apply Simulated Annealing (SA) to solve the nonlinear model such that the ECG signals with embedded patients' confidential data have good SNR, good root mean square error (RMSE), and high similarity. In other words, the distortion of the PQRST complexes and the ECG shape caused by the embedded patients' confidential data is very small, and thus the quality of the embedded ECG signals meets the requirements of physiological diagnostics. In the terminals, one can receive the ECG signals with the embedded patients' confidential data. In addition, the embedded patients' confidential data can be received and extracted without the original ECG signals. The experimental results confirm the efficiency that our method maintains a high quality of each ECG signal with the embedded patient confidential data. Moreover, the embedded confidential data shows a good robustness against common attacks.


Assuntos
Eletrocardiografia , Processamento de Sinais Assistido por Computador , Humanos , Eletrocardiografia/métodos , Razão Sinal-Ruído , Modelos Teóricos , Atenção à Saúde , Algoritmos
2.
Korean J Physiol Pharmacol ; 23(3): 161-169, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31080347

RESUMO

Fumigaclavine C (FC), an active indole alkaloid, is obtained from endophytic Aspergillus terreus (strain No. FC118) by the root of Rhizophora stylosa (Rhizophoraceae). This study is designed to evaluate whether FC has anti-adipogenic effects in 3T3-L1 adipocytes and whether it ameliorates lipid accumulation in high-fat diet (HFD)-induced obese mice. FC notably increased the levels of glycerol in the culture supernatants and markedly reduced lipid accumulation in 3T3-L1 adipocytes. FC differentially inhibited the expressions of adipogenesis-related genes, including the peroxisome proliferator-activated receptor proteins, CCAAT/enhancer-binding proteins, and sterol regulatory element-binding proteins. FC markedly reduced the expressions of lipid synthesis-related genes, such as the fatty acid binding protein, lipoprotein lipase, and fatty acid synthase. Furthermore, FC significantly increased the expressions of lipolysis-related genes, such as the hormone-sensitive lipase, Aquaporin-7, and adipose triglyceride lipase. In HFD-induced obese mice, intraperitoneal injections of FC decreased both the body weight and visceral adipose tissue weight. FC administration significantly reduced lipid accumulation. Moreover, FC could dose-dependently and differentially regulate the expressions of lipid metabolism-related transcription factors. All these data indicated that FC exhibited anti-obesity effects through modulating adipogenesis and lipolysis.

3.
Sci Rep ; 12(1): 21339, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36494500

RESUMO

Nonlinear phenomenon is presently attracting considerable attention in the field of microelectromechanical systems (MEMS). By adjusting a controllable tuning voltage, the nonlinearity of microdevices, especially on microactuators, can be precisely manipulated. To trap and separate small particles, generating a large and stable rotation force is critical in micromanipulations. Here, we report a simple and potential angular momentum cell comprising a piezoelectric MEMS-based nonlinear multi-mode resonator with integrated electrodes. A nonlinear rotating nodal line has been observed in specific frequency bands by applying a controllable low voltage of sub 5 V on a 4-port resonator made of lead zirconate titanate (PZT) thin films. The magnitude of the actuated voltage is Complementary-Metal-Oxide-Semiconductor (CMOS)-compatible and easy to integrate with the circuit. Furthermore, the real-time rotation motion of the MEMS-based nonlinear multi-mode resonator is also verified by a laser doppler vibrometer (LDV) at both chirp and single input frequencies, respectively. Therefore, this angular momentum cell shows great potential in the application of micromanipulation.

4.
Comput Med Imaging Graph ; 32(7): 601-10, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18722751

RESUMO

Automation of liver positron emission tomography (PET) image segmentation is proposed in this paper. A new active contour model (ACM), called Poisson Gradient Vector Flow (PGVF), with genetic algorithm (GA) constructs a scheme to automatically find the contour of liver in the PET images. PET is widely used for the clinical purpose, but image quality of PET makes the image segmentation be a tough work. Three image data sets are tested for evaluating the new segmentation approach of liver PET images. One image data set is adapted from the study of one person with a normal liver. The other two image data sets are adapted from the studies of two patients with abnormal livers. The results show that the regions of interest (ROI) of liver are automatically segmented from the images of three data sets.


Assuntos
Algoritmos , Inteligência Artificial , Interpretação de Imagem Assistida por Computador/métodos , Fígado/diagnóstico por imagem , Reconhecimento Automatizado de Padrão/métodos , Humanos , Aumento da Imagem/métodos , Cintilografia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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