A Single-Clamp Inchworm Actuator with Two Piezoelectric Stacks.

Inchworm piezoelectric actuators have attracted much attention in the field of precision positioning due to the advantages of a large stroke, high output force, and high resolution. However, traditional inchworm piezoelectric actuators use two sets of clamps and a set of drive structures to achieve stepping motion, which generally requires at least three piezoelectric stacks, resulting in a complex structure and the control system. Several methodologies have been advanced to minimize the utilization of piezoelectric stacks. However, there still exists the issue of excessive volume. Therefore, an inchworm piezoelectric actuator with a single-clamp and single drive structure is proposed in the study, which provides a compact size and smaller volume. The clamping mechanism comprises two sets of clamping feet with opposite displacement, which alternate contact with the guide frame and adjustable plate to ensure that the clamping mechanism always has frictional force and accomplishes the stepping motion. The testing of the actuator's step distance, output force, and other parameters was conducted utilizing a displacement sensor. Experimental results indicate that the actuator achieved a maximum speed of 174.3 µm/s and an output force of 8.6 N when the frequency and voltage were 19 Hz and 150 V.

Using Logistic Multivariate Analysis to Explore the Effects of Nursing and Psychological Factors on Motor and Cognitive Rehabilitation in Patients with Stroke: Based on a Retrospective Case-Control Study.

Objective: Based on a retrospective case-control study, logistic multivariate analysis was employed to explore the effects of nursing and psychological factors on the rehabilitation of motor and cognitive function in patients with stroke. Methods: A total of 200 stroke patients treated from February 2019 to April 2020 were enrolled in our hospital. According to the results of exercise and cognitive rehabilitation, the patients with good rehabilitation were divided into the control group (n = 140) and the research group (n = 60). The effects of nursing and psychological factors on the rehabilitation of motor and cognitive function in patients with stroke were analyzed. Results: First of all, we compared the general data. There were significant differences in terms of age, years of education, occupational status, payment methods of medical expenses, family income and the course of the disease, and the difference was statistically significant (P < 0.05). There was no significant difference in general data (P > 0.05). Secondly, we compared the nursing effective rates. The nursing effective rates of the study group were 10 cases, 15 cases, 12 cases, and 23 cases, and the nursing effective rate was 61.67%. In the control group, 78 cases were markedly effective, 33 cases were effective, 25 cases were general and 14 cases were ineffective, and the nursing effective rate was 90.00%. The effective rate of nursing in the study group was higher than that in the control group, and the difference was statistically significant (P < 0.05). There was no significant difference in anxiety and depression scores before nursing (P > 0.05), but they decreased after nursing. In addition, the scores of anxiety and depression in the study group were higher than those in the control group, and the difference was statistically significant (P < 0.05). There was no significant difference in motor function and cognitive function between prenursing and prenursing (P > 0.05); after nursing, the motor function increased and the score of cognitive function decreased. Furthermore, the motor function of the study group was lower compared to the control group, and the score of cognitive function of the study group was higher compared to the control group, and the difference was statistically significant (P < 0.05). The results of the Person correlation analysis showed that there was a significant correlation between nursing anxiety depression and the rehabilitation effect of motor cognitive function in stroke patients. The results of logistic regression analysis showed that age, family income, nursing efficiency, anxiety, and depression were the factors affecting the rehabilitation of motor and cognitive function in stroke patients. Conclusion: Age and family income may be the risk factors affecting the psychological mood of patients. Medical staff should pay attention to the negative emotion of patients and strengthen the nursing intervention of patients.

Effectiveness of repetitive transcranial magnetic stimulation on poststroke dysphagia: a meta-analysis of randomized-controlled trials.

Dysphagia is a common functional impairment after stroke, resulting in aspiration of liquids, ingested foods, or oral secretions and influencing the quality of life. Noninvasive repetitive transcranial magnetic stimulation has been widely used for rehabilitation of dysphagia. The purpose of this meta-analysis was to investigate the efficacy of repetitive transcranial magnetic stimulation on poststroke swallowing impairment. Four databases were systematically searched for eligible studies from their inception to 31 September 2021. Review Manager 5.4 software was used for this meta-analysis. The bias of included randomized controlled trials was assessed using the version 2 of the Cochrane risk-of-bias tool for randomized trials. Nine randomized controlled trials involving 393 patients were included according to the selection criteria. The results revealed significant benefit of repetitive transcranial magnetic stimulation as a treatment of dysphagia following the onset of stroke, when compared with intervention without repetitive transcranial magnetic stimulation. Applying repetitive transcranial magnetic stimulation on different stimulation sites effectively improved the dysphagia of poststroke patients, and no significant difference was observed among the different stimulation sites subgroups. Our findings support repetitive transcranial magnetic stimulation as an effectively treatment of the poststroke dysphagia, especially in unilateral hemispheric stroke patients.

Upregulated C-C Motif Chemokine Ligand 2 Promotes Ischemic Stroke via Chemokine Signaling Pathway.

BACKGROUND: This study aims to evaluate the potential effect and the underlying mechanism of C-C motif chemokine ligand 2 (CCL2) in ischemic stroke. METHODS: An integrated bioinformatics analysis was performed to identify the differentially expressed (DE) genes and their related pathways in ischemic stroke. In vivo study of a rat model of middle cerebral artery occlusion (MCAO) was further established to assess the effect of CCL2 on severity of neurologic impairments. The expression levels of proinflammatory cytokines were also evaluated using the ELISA assay, and Western blot was also used to determine the expression of CCL2 and other DE proteins in the related pathways. RESULTS: A total of 88 DE genes were identified from the microarray dataset of ischemic stroke. The bioinformatics analysis revealed that CCL2 was highly expressed in ischemic stroke tissue and promoted the ischemic stroke progression via activation of the chemokine signaling pathway and cytokine-cytokine receptor interaction pathway. The in vivo study of the ischemic stroke rat model also showed that the CCL2 expression was elevated in the MCAO/R rats, with significant neurological impairments and ischemic infarct area in the brain tissue being observed. The administration of CCL2 inhibitors significantly inhibited the inflammatory response, attenuated the neurological impairments, and decreased the ischemic infarct area in the MCAO/R rats. Furthermore, the downregulation of CCL2 also inhibited the expression of the pathway-related proteins including CCL7, CCR2, CXCL16, and TNF-α. CONCLUSIONS: These results indicate that the CCL2/chemokine signaling pathway is responsible for ischemic stroke progression and might represent a potential therapeutic target for ischemic stroke treatment.