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1.
Article in English | MEDLINE | ID: mdl-38082969

ABSTRACT

Facial stimulation can produce specific event-related potential (ERP) component N170 in the fusiform gyrus region. However, the role of the fusiform gyrus region in facial preference tasks is not clear at present, and the current research of facial preference analysis based on EEG signals is mostly carried out in the scalp domain. This paper explores whether the region of the fusiform gyrus is involved in processing face preference emotions in terms of the distribution of energy over the source domain, and finds that the pars orbitalis cortex is most energetically active in the face preference task and that there are significant differences between the left and right hemispheres.Clinical Relevance- The role of pars orbitalis in facial preference may help doctors determine whether the pars orbitalis cortex is lost in clinical practice.


Subject(s)
Electroencephalography , Evoked Potentials , Evoked Potentials/physiology , Cerebral Cortex , Temporal Lobe/physiology , Emotions/physiology
2.
Ultrasonics ; 131: 106965, 2023 May.
Article in English | MEDLINE | ID: mdl-36854246

ABSTRACT

In this study, a novel miniature I-shaped linear ultrasonic motor is proposed. The motor is constructed by two rectangular piezoelectric vibrators which are mounted in parallel with the slider to make the structure look like the letter "I". The symmetric and antisymmetric modes of the motor based on the first-order flexural vibrations of the two vibrators are chosen as the working modes. The finite element method is adopted to optimize the structure and study the vibration behavior of the motor. A prototype of the proposed linear ultrasonic motor is fabricated and its mechanical characteristics are tested. The dimension of the stator is 39.8 × 17.6 × 6 mm3 and the weight of the prototype is only 18.2 g. The typical outputs of the prototype are maximum speed of 364 mm/s, maximum thrust of 500 g and thrust-weight ratio of 24.47. The experimental results confirm that the developed linear ultrasonic motor has the advantages of structural design and miniaturization.

3.
Ultrasonics ; 124: 106717, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35278803

ABSTRACT

To achieve larger thrust and higher power in applications, multiple linear ultrasonic motors are usually combined. However, in previous researches, the motion mechanism of bundled linear ultrasonic motors is not explained clearly. Most researchers focus upon the description of experiments and the interpretation of experimental results, therefore until now, the dynamic model of the bundled linear ultrasonic motors has not been well established. In order to obtain deeper physical insight into the motion principle and provide a theoretical basis for better control of the bundled linear ultrasonic motors, a dynamic model for bundled linear ultrasonic motors is established in this paper. In this model, the contact interface is simplified to be a single point contact model and the impact of the clamping part on the performance of motor is considered. Using this model, the output characteristics of the bundled linear ultrasonic motors are investigated by discussing the influence of some important factors including preload, exciting voltage and exciting frequency. Test results show the proposed dynamic model is able to predict the output performance of the bundled motors. Moreover, the proposed model is not only suitable for the researched motor, but also can be extended to other bundled linear ultrasonic motors.


Subject(s)
Ultrasonics , Equipment Design , Motion
4.
Cell Mol Biol (Noisy-le-grand) ; 65(7): 127-131, 2019 Sep 30.
Article in English | MEDLINE | ID: mdl-31880530

ABSTRACT

To investigate the relationship between the Erk1/2 signal pathway and neuronal apoptosis in ischemic stroke rats. Male SD(Sprague Dawley)  rats (n = 24) were randomly divided into three groups, each containing 8 rats: sham-operated group, MCAO(Midle cerebral artery oclusion)  group, and MCAO + U0126 intervention group (U0126 group). In in vitro trial, primary cortical nerve cells were divided into three groups: control group, OGD(Oxygen and glucose deprivation)  group, and U0126 intervention group (U0126 group). In vivo protein expression levels of Erk1/2, p-Erk1/2 and Bcl-2 were determined using western blot. The expressions of Bcl-2, Bcl-xl and Bax were assayed using immunohistochemical staining. Nerve cell mortality in cerebral tissue was detected using TUNEL staining. In in vitro trials, cell apoptosis was assayed with flow cytometry and LDH release. The activity of caspase-3 was determined. Nerve cell apoptosis was determined using Hoechst33258 staining method. In in vivo trial, it was found that the protein expression level of p-ERK1/2 in cerebral tissue in the MCAO group was significantly increased, when compared with that of the sham-operated group, while the protein expression level of p-Erk1/2 in the U0126 group was significantly lower than that in the MCAO group. The expression levels of Bcl-2 and Bcl-xl in the MCAO group were significantly lower than the corresponding expression levels in the sham-operated group, while the expressions of Bcl-2 and Bcl-xl in the U0126 group were significantly lower than those in MCAO group. In MCAO group, the expression of Bax was significantly higher than that in the sham-operated group, while Bax expression was higher in U0126 than in MCAO group. There were significantly higher number of dead nerve cells in MCAO group than in the sham-operated group, while nerve cell mortality in U0126 group was significantly lower than in MCAO group. In in vitro trials, flow cytometry revealed significantly higher apoptosis of OGD-treated nerve cells, relative to the control group. Nerve cells exposed to U0126 and treated with ODR (Oxygen-dependent repressor)  were significantly decreased in population, when compared with single OGD treatment group. The LDH release level of nerve cells treated OGD was significantly increased, when compared with that of the control group. However, LDH release level of nerve cells treated with OGD after U0126 intervention was significantly decreased, relative to the single OGD treatment group. The dilution of nerve cell nucleus after OGD treatment was significantly increased, when compared with that of the control group. For nerve cells treated with ODR after U0126 intervention, the nuclear dilution was significantly decreased, relative to that of nerve cell nucleus in the single OGD treatment group. The OGD treatment led to significant increase in nerve cell caspase-3 activity, relative the control group. However, the caspase-3 activity of nerve cells treated with ODR after U0126 intervention was significantly decreased, when compared with single OGD treatment group. The activation of Erk1/2 signal pathway during ischemic stroke promotes apoptosis of nerve cells. Based on these findings, it can be reasonably inferred that the ERK1/2 signal pathway may be an important target for treating ischemic stroke.


Subject(s)
Brain Ischemia/metabolism , Animals , Apoptosis/drug effects , Apoptosis/genetics , Apoptosis/physiology , Brain Ischemia/pathology , Butadienes/pharmacology , Caspase 3/genetics , Caspase 3/metabolism , Cerebral Cortex/cytology , Cerebral Cortex/metabolism , In Situ Nick-End Labeling , MAP Kinase Signaling System/drug effects , MAP Kinase Signaling System/genetics , MAP Kinase Signaling System/physiology , Male , Nitriles/pharmacology , Proto-Oncogene Proteins c-bcl-2/genetics , Proto-Oncogene Proteins c-bcl-2/metabolism , Random Allocation , Rats , Rats, Sprague-Dawley , bcl-2-Associated X Protein/genetics , bcl-2-Associated X Protein/metabolism , bcl-X Protein/genetics , bcl-X Protein/metabolism
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