This paper presents a novel double-direction inchworm in-pipe robot, called the Cam-Linkage Robot (CLR), used to carry sensors and instruments to perform inspection and cleaning jobs inside ...pipelines. The prototype has been developed to improve the driving ability and reduce the difficulty of control. CLR is suitable for pipe diameters from 360 mm to 400 mm due to its functions of manual adjustment and automatic adaptation. The structure of CLR was presented and some critical design issues on the principle of cam-linkage mechanism were discussed. Based on cam-linkage mechanism, CLR could press the wall actively and creep in two directions via only one motor, so this research has broken the limitation that traditional active wall-press robot needs more than one actuator. The cam pressure angle could be reduced to 0, and the propulsion ability was almost not weakened by the support motion at the stable support stage. Finally, experiments were conducted to validate the locomotion principle and the effectiveness of CLR.
The peristaltic in-pipe robot incorporates multiple actuators, and achieving precise cooperative control among these actuators poses significant complexity. To address these issues, the Theory of ...Inventive Problem Solving (TRIZ) is applied to identify and resolve physical and technical conflicts in the creative design process of peristaltic in-pipe robots. By highlighting the insights on and technical guidance offered by TRIZ’s inventive principles, this paper examines the method for realizing a single-motor-driven peristaltic in-pipe robot from a transmission perspective. By employing a combination of connecting rods, cam mechanisms, and gear systems, a one-DOF peristaltic in-pipe robot was devised. Subsequently, a prototype was constructed, and successful bidirectional motion tests were conducted within pipes. The findings highlight the efficacy of the TRIZ-based design approach in innovatively designing one-DOF in-pipe robots and the unnecessary employment of complex multi-drive cooperative control in peristaltic in-pipe robots.
The inchworm in-pipe robot has the advantages of stable support, low walking resistance, and high flexibility. However, the gait motion of in-pipe robots relies on the precise coordination of three ...motors, which greatly increases the complexity of control. To solve this problem, an inchworm in-pipe robot based on a multi-cam combination is proposed. The robot needs only one motor to achieve active support and bidirectional crawling for the pipe wall, mainly used for detecting straight pipelines, such as the main drainage pipeline. In order to obtain the periodic motion law and characteristics of the inchworm in-pipe robot, structure design, constraint analysis, and dynamic simulation were carried out on the robot. Finally, the principle prototype was tested in the transparent pipe, the test results indicate that the robot can achieve bidirectional creep under a single motor drive, which can simplify the control of gait motion for inchworm in-pipe robots. The average displacement errors for horizontal walking and vertical walking are 2.0% and 11.3%, respectively, due to factors such as gravity. Therefore, the robot can achieve a more accurate step distance in horizontal pipelines.
Parkinson's disease (PD) is a quite common neurodegenerative disorder with a prevalence of approximately 1:800-1,000 in subjects over 60 years old. The aim of our study was to determine the candidate ...target genes in PD through meta-analysis of multiple gene expression arrays datasets and to further combine mRNA and miRNA expression analyses to identify more convincing biological targets and their regulatory factors. Six included datasets were obtained from the Gene Expression Omnibus database by systematical search, including five mRNA datasets (150 substantia nigra samples in total) and one miRNA dataset containing 32 peripheral blood samples. A chip meta-analysis of five microarray data was conducted by using the metaDE package and 94 differentially expressed (DE) mRNAs were comprehensively obtained. And 19 deregulated DE miRNAs were obtained through the analysis of one miRNAs dataset by Qlucore Omics Explorer software. An interaction network formed by DE mRNAs, DE miRNAs, and important pathways was discovered after we analyzed the functional enrichment, protein-protein interactions, and miRNA targetome prediction analysis. In conclusion, this study suggested that five significantly downregulated mRNAs (MAPK8, CDC42, NDUFS1, COX4I1, and SDHC) and three significantly downregulated miRNAs (miR-126-5p, miR-19-3p, and miR-29a-3p) were potentially useful diagnostic markers in clinic, and lipid metabolism (especially non-alcoholic fatty liver disease pathway) and mitochondrial dysregulation may be the keys to biochemically detectable molecular defects. However, the role of these new biomarkers and molecular mechanisms in PD requires further experiments
and
and further clinical evidence.
Ischemic Stroke (IS) is the most common neurological emergency disease and has become the second most frequent cause of death after coronary artery disease in 2015. Owing to its high fatality rate ...and narrow therapeutic time window, early identification and prevention of potential stroke is becoming increasingly important.
We used meta-analysis and bioinformatics mining to explore disease-related pathways and regulatory networks after combining messengerRNA (mRNA) and miRNA expression analyses. The purpose of our study was to screen for candidate target genes and microRNA(miRNA) for early diagnosis of potential stroke.
Five datasets were collected from the Gene Expression Omnibus (GEO) database by systematical retrieval, which contained three mRNA datasets (102 peripheral blood samples in total) and two miRNA dataset (59 peripheral blood samples). Approximately 221 different expression(DE) mRNAs (155 upregulated and 66 downregulated mRNAs) and 185 DE miRNAs were obtained using the metaDE package and GEO2R tools. Further functional enrichments of DE-mRNA, DE-miRNA and protein-protein interaction (PPI) were performed and visualized using Cytoscape.
Our study identified six core mRNAs and two regulated miRNAs in the pathogenesis of stroke, and we elaborated the intrinsic role of systemic lupus erythematosus (SLE) and atypical infections in stroke, which may aid in the development of precision medicine for treating ischemic stroke. However, the role of these novel biomarkers and the underlying molecular mechanisms in IS require further fundamental experiments and further clinical evidence.
Objective
The aim of the study was to evaluate non-invasive brain stimulation (NIBS) including transcranial magnetic stimulation (TMS) and transcranial electrical stimulation (tES) on neurological ...symptoms in patients with multiple sclerosis (PwMS).
Method
We searched PubMed, Embase, Cochrane Library, Web of Science and Ovid MEDLINE until February 2022. And we evaluated the included studies for methodological quality by the Cochrane bias risk assessment tool and assessed the studies' certainty of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework. We performed network meta analysis (NMA) by using Stata 15 and ranked the results of the NMA by using the surface under the cumulative ranking curve (SUCRA) ranking chart.
Result
Twenty seven clinical trials were finally included (
N
= 596, 66.4% women). For the immediate effects, rTMS over M1 yielded the most optimal scheme for fatigue reduction among all the interventions compared to the sham stimulation groups MD = −0.85, 95% CI (−1.57, −0.14) (SUCRA = 82.6%). iTBS over M1 yielded the most signifcant reduced pain level than the sham groups did MD = −1.26, 95% CI (−2.40, −0.11) (SUCRA = 98.4%). tDCS over F3 was the best protocol of NIBS to improve quality of life (QOL) MD = 1.41, 95% CI = (0.45,2.36) (SUCRA = 76.7%), and iTBS over M1 may significantly reduce spasticity compared to sham stimulation MD = −1.20, 95% CI = (−1.99, −0.41) (SUCRA = 90.3%). Furthermore, rTMS, tRNS, and tDCS on certain areas may improve PwMS accuracy, response time, manual dexterity, pain relief and QOL, but does not show statistically significant differences. The evidence assessed using GRADE is very low.
Conclusion
Based on the NMA and SUCRA ranking, we can conclude that symptoms including fatigue, pain, spasticity, and QOL can be improved by following NIBS protocol after treatment. Nonetheless, most of the included studies lack a good methodology, and more high-quality randomized clinical trials are needed.
Regenerative chatter is a self-excited vibration that may take place during milling, which process could shorten the lifetime of the tool and result in unacceptable surface quality. Thus, it is ...necessary to predict and avoid the appearance of this instability phenomenon. In this paper, an improved complete discretization method is proposed to predict milling stability. The highlight of this algorithm is that, by using Euler’s method, it discretizes periodic coefficient matrices, delay term, time domain term, and the differential terms, In search of convenience, the benchmark examples are illustrated by making a comparison among the semi-discretization method, complete discretization scheme, and improved complete discretization method, while at the same time the accuracy and efficiency of the algorithm is demonstrated. The results show that the proposed method is provided with higher computational efficiency and better industrial application value.
It is well known that the immune response plays an important role in eliminating or controlling the disease after human body is infected by virus. In this paper, we investigate the dynamical behavior ...of a viral infection model with retarded immune response. The effect of time delay on stability of the equilibria of the system has been studied and sufficient condition for local asymptotic stability of the infected equilibrium and global asymptotic stability of the infection-free equilibrium and the immune-exhausted equilibrium are given. By numerical simulating,we observe that the stationary solution becomes unstable at some critical immune response time, while the delay time and birth rate of susceptible host cells increase, and we also discover the occurrence of stable periodic solutions and chaotic dynamical behavior. The results can be used to explain the complexity of the immune state of patients.
Objective. Systemic lupus erythematosus (SLE) is an immune disease characterized by multiorgan involvement. Neuropsychiatric systemic lupus erythematosus (NPSLE) is one of the most devastating ...complications of SLE, which lacks efficient diagnostic biomarkers. The recent studies on the anti-GAPDH autoantibodies suggested its potential pathogenic roles in NPSLE. However, the clinical relevance of the anti-GAPDH autoantibodies in patients with SLE is still elusive. In this study, we sought to determine the serum levels of the anti-GAPDH autoantibodies in patients with SLE to investigate the clinical significance of the anti-GAPDH autoantibodies in SLE. Methods. Concentrations of the glyceraldehyde 3-phosphate dehydrogenase autoantibodies (anti-GAPDH autoantibodies) in the serum of 130 SLE patients and 55 healthy individuals were determined by enzyme-linked immunosorbent assay (ELISA). Among the 130 SLE patients, 95 were SLE patients without neuropsychiatric symptoms and 35 had NPSLE. White blood cell (WBC) count, hemoglobin (HB), platelet count (PLT), IgG, IgA, IgM, anti-dsDNA, C3, C4, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), RF, anti-cardiolipin (Acl), ANA, AnuA, anti-SSA, anti-SSB, β2-GPI, urinalysis, and 24 h urine protein were measured by standard laboratory techniques. Systemic lupus erythematosus disease activity index 2000 (SLEDAI-2K) and Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) damage index scores were evaluated accordingly. Results. The serum levels of the anti-GAPDH autoantibodies were significantly elevated in the SLE patients, especially in the patients with NPSLE (P=0.0011). Elevated serum anti-GAPDH was correlated with increased SLEDAI-2K (P=0.017), ESR, IgG, and IgM and associated with increased intracranial pressure and incidence of cerebrovascular lesions, but it was protective for seizure disorder incidence. Conclusions. Serum anti-GAPDH autoantibody was increased in both groups of SLE patients with or without neuropsychiatric symptoms and associated with disease severity. It could become an indicator of tissue damages in the brain for the future clinical practice.
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