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1.
Sci Rep ; 13(1): 14486, 2023 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-37660229

RESUMO

The novel fault diagnosis method of gearbox based on Fourier Bessel series expansion-based empirical wavelet transform (FBEWT) and manifold regularization extreme learning machine (MRELM) is proposed to obtain excellent fault diagnosis results of gearbox in this paper. A new feature extraction strategy based on Fourier Bessel series expansion-based empirical wavelet transform is used to capture the key non-stationary features of the vibrational signal of gearbox, and significantly improve the diagnosis ability of gearbox. The ELM with manifold regularization is proposed for fault diagnosis of gearbox. In order to outstand the superiority and stability of the proposed FBEWT and manifold regularization ELM, the balanced dataset and unbalanced dataset, respectively, are used. The experimental results testify that FBEWT-MRELM are more superior and stable than FBEWT-ELM, EWT-MRELM, and EWT-ELM regardless of balanced dataset and unbalanced dataset.

2.
Toxicol Appl Pharmacol ; 477: 116674, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37648088

RESUMO

Vesicular monoamine transporter 2 (VMAT-2) functions by uptake of cytoplasmic monoamines into vesicles for storage. Valbenazine (VBZ) is a newly FDA-approved oral VMAT-2 inhibitor used for the treatment of movement disorders such as tardive dyskinesia (TD), and Tourette syndrome (TS). Clinical data shows that VBZ is a relatively safe drug with no cardiotoxicity or hepatotoxicity. However, the effect of VBZ on embryonic development remains unknown. Here, we use zebrafish larvae as an animal model to demonstrate that VBZ exposure causes premature hatching and increased body size and hyperactivity-like behaviors in zebrafish larvae. In addition, VBZ exposure leads to increased dopamine (DA) and Glutamate (Glu) levels. Moreover, an increase of growth hormone (gh) and enriched PI3K/AKT signaling were found in VBZ-exposed zebrafish larvae, which may explain their accelerated development. In summary, VBZ exposure may be developmentally toxic in zebrafish larvae.

3.
Ecotoxicol Environ Saf ; 262: 115284, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37556957

RESUMO

Monoamine oxidase-B (MAO-B), as a principal metabolizing enzyme, plays important roles in the metabolism of catecholamines and xenobiotics in the central nervous system and peripheral tissues. Safinamide, the third-generation reversible MAO-B inhibitor, has potential to alleviate many neurological diseases such as Parkinson's disease (PD) and depression. Exposure to clinical psychotropic drugs often has adverse effects on fetuses. Currently, a variety of studies of safinamide focus on its curative effect and pharmacological effect, while its side effect of embryonic development is barely studied. In this study, we used zebrafish as a model to evaluate the embryonic developmental toxicity of safinamide. Our results revealed that higher concentrations (30 µM) of safinamide treatment caused a decrease in hatching rate and an increase in malformation and mortality in zebrafish larvae. Meanwhile, we observed that lower safinamide exposure (10 µM) increased the body length of zebrafish larvae and resulted in hyperactivity-like behaviors. In addition, an increased trend in dopamine (DA) level was found in 3.3 µM and 10 µM safinamide-exposed groups. Transcriptome analysis identified that safinamide exposure may disturb a variety of physiological processes such as neuroactive ligand-receptor interaction signaling pathway. In summary, our study reveals that safinamide may cause developmental defects in zebrafish larvae and provides insights into its toxic reactions in early develoment.

4.
Med Devices (Auckl) ; 9: 27-32, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26848279

RESUMO

Wireless capsule endoscope achieved great success, however, the maneuvering of wireless capsule endoscope is challenging at present. A magnetic driving instrument, including two bar magnets, a stepper motor, a motor driver, a motor controller, and a power supplier, was developed to generate rotational magnetic fields. Permanent magnet ring, magnetized as S and N poles radially and mounted spiral structure on the surface, acted as a capsule. The maximum torque passing to the capsule, rotational synchronization of capsule and motor, and the translational speed of capsule, were measured in ex vivo porcine large intestine. The experimental results illustrate that the rotational movement of the spiral-type capsule in the intestine is feasible and the cost of the magnetic driving equipment is low. As a result, the solution is promising in the future controllability.

5.
Med Devices (Auckl) ; 8: 141-51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25733935

RESUMO

To actively maneuver a robotic capsule for interactive diagnosis in the gastrointestinal tract, visualizing accurate position and orientation of the capsule when it moves in the gastrointestinal tract is essential. A possible method that encloses the circuits, batteries, imaging device, etc into the capsule looped by an axially magnetized permanent-magnet ring is proposed. Based on expression of the axially magnetized permanent-magnet ring's magnetic fields, a localization and orientation model was established. An improved hybrid strategy that combines the advantages of particle-swarm optimization, clone algorithm, and the Levenberg-Marquardt algorithm was found to solve the model. Experiments showed that the hybrid strategy has good accuracy, convergence, and real time performance.

6.
Med Devices (Auckl) ; 7: 283-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25170283

RESUMO

To control and drive a robotic capsule accurately from outside a patient's body, we present a schema in which the capsule enclosing the imaging device, circuits, batteries, etc is looped by a permanent magnet ring that acts as an actuator. A cuboidal permanent magnet situated outside the patient's body attracts or pushes the magnet ring from different directions to make the capsule move or rotate. A mathematic model of attractive or repulsive force that the cuboidal magnet exerts on the magnet ring is presented for accurate calculation of force. The experiments showed that the measuring force was in agreement with the theoretical one, and the relations between the dimensions of the cuboidal magnet and force are useful to produce a cuboidal magnet with optimal shape to get appropriate force.

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