Permanence for a Delayed Nonautonomous SIR Epidemic Model with Density-Dependent Birth Rate

Based on some well-known SIR models, a revised nonautonomous SIR epidemic model with distributed delay and density-dependent birth rate was considered. Applying some classical analysis techniques for ordinary differential equations and the method proposed by Wang (2002), the threshold value for the permanence and extinction of the model was obtained

Application and Design of Inspection Robot System Based on Multi-parameter Hierarchical Inspection of UHV Substation

In this paper, a new substation inspection robot system is introduced, to meet the application requirements of multi-parameter full-station automatic hierarchical inspection of the insulation status of power equipment in UHV ( Ultra-High Voltage ) substation. The system is designed to control the inspection of substation robots, including identifying the number of meters on the cabinet, measuring partial discharge, measuring temperature and humidity and so on . The system is divided into two parts. One part runs in the robot body ,which is called the body control system , and it contains web server, robot ground control system and database. The other part runs on external industrial computer, which is called station control service system. The function of the body control system is more specific, mainly for controlling its own motor driver, in order to complete its own motion. The station control service system achieves important logic control, including configuring inspection plan, visual recognition, robot walking path planning, and writing inspection results into the database

Analysis of Distortion Based on 2D MEMS Micromirror Scanning Projection System

To analyze the distortion problem of two-dimensional micro-electromechanical system (MEMS) micromirror in-plane scanning, this paper makes a full theoretical analysis of the distortion causes from many aspects. Firstly, the mathematical relations among the deflection angle, laser incidence angle, and plane scanning distance of the micromirror are constructed, and the types of projection distortion of the micromirror scanning are discussed. Then the simulation results of reflection angle distribution and point cloud distribution are verified by MATLAB software under different working conditions. Finally, a two-dimensional MEMS micromirror scanning projection system is built. The predetermined waveform can be scanned and projected successfully. The distortion theory is proved to be correct by analyzing the distortion of the projection images, which lays a foundation for practical engineering application

A wide-area protection method based on directional traveling wave energy

In order to improve the reliability in traditional traveling wave protection, a wide-area protection method based on directional traveling wave energy was proposed in this paper. Firstly, the association matrix of transmission line/traveling wave protection device was established according to the connection relationship between transmission lines and traveling wave protection devices. Secondly, the fault direction could be identified by calculating the square ratio of positive and negative direction traveling wave energy. Then, the fault association matrix could be obtained by the specific determination principle between the recorded fault direction judgment results and the element in the fault association matrix, the fault line was thus determined. Simulation results showed that the proposed method was not only simple and feasible, but also fast and reliable. The fault line still could be correctly identified when the traveling wave protection device failed to start, the reliability and practicability of traveling wave protection were greatly improved

A Bayesian method for 3D estimation of subcellular particle features in multi-angle TIRF microscopy

Multi-angle total internal reflection fluorescence microscopy (MA-TIRFM) is a relatively new and powerful tool to study subcellular particles near cell membrane due to its unique illumination mechanism. We present a MAP-Bayesian method to automatically estimate features of individual particles in MA-TIRF images, including 3D positions, relative sizes, and relative amount of fluorophores. Using the MAP criterion, the optimal values of the features can be obtained by maximizing a nonlinear functional. Initial feature values are estimated by using image filters and clustering algorithms. The method is evaluated on synthetic data and results show that it has high accuracy. The result on real data from our initial experiments is also presented

Automatic detection of subcellular particles in fluorescence microscopy via feature clustering and bayesian analysis

Recent advancement in live cell fluorescence microscopy has enabled image acquisition at single particle resolution, through which biologists can investigate the underlying mechanisms of cellular processes. In this paper, we present a method to automatically detect the features of sub-cellular particles in 2D fluorescence images, including x-y positions, fluorescence intensities, and relative sizes. The method consists of two parts. One is an initial detection method, which finds particle candidates in the images using image filters and clustering algorithms. The other is a MAP-Bayesian based estimation method, which provides the optimal estimations of particle features. The method is evaluated on synthetic data and results show that it has high accuracy. The results on real data confirmed by human expert cell biologists are also presented

Establishment of rat ankle post-traumatic osteoarthritis model induced by malleolus fracture

Abstract Background Malleolar fracture, which is present in 37–53% of human ankle osteoarthritis (OA), is the most common type of fracture in the ankle joint. In spite of this, no rat animal model has been developed for this type of injury to date. Here, we established a rat ankle post-traumatic OA (PTOA) model induced by malleolar fracture; this model will be useful in ankle OA research. Methods Two-month-old male Sprague Dawley (SD) rats were randomized into 2 groups (n = 19 per group): 1) malleolus articular fracture, dislocation, and immediate reduction on the right joints and 2) malleolus articular fracture on the right ankle. The contralateral ankle joints were used as controls. The fracture and healing processes were confirmed and monitored by radiography. Changes in inflammation were monitored in vivo by fluorescence molecular tomography (FMT). Cartilage damage and changes in expression of OA-related genes were analyzed by histology, immunohistochemistry, Real-time quantitative PCR (qPCR) and enzyme-linked immunosorbent assay (ELISA) at 8 weeks post-surgery. Results X-rays showed that all fractures were healed at 8 weeks post-surgery. A reproducible, mild to moderate degree of OA cartilage damage with reduced aggrecan was detected by histology in all animals in both groups but there was no significant difference between the two groups. Decreased Col-II and increased Col-X and MMP-13 levels were detected by qPCR, immunohistochemistry, ELISA and FMT from both groups cartilage. Conclusions Malleolus articular fracture alone induces ankle OA with lesions on the central weight bearing area of the tibiotalar joint in rats. This model will provide a reproducible and useful tool for researchers to study ankle OA

A prognostic signature consisting of N6-methyladenosine modified mRNAs demonstrates clinical potential in prediction of biochemical recurrence and guidance on precision therapy in prostate cancer

Novel biomarkers are urgently needed to improve the prediction of clinical outcomes and guide personalized treatment for prostate cancer (PCa) patients. However, the role of N6-methyladenosine (m6A) modifications in PCa initiation and progression remains largely elusive. In our study, we collected benign Prostate Hyperplasia (BPH), localized PCa, and metastatic PCa samples from patients and performed methylated RNA immunoprecipitation sequencing (MeRIP-Seq) to map m6A-methylated mRNAs. Furthermore, we developed a prognostic signature based on 239 differentially methylated RNAs and the TCGA-PRAD dataset, which can be used to calculate an m6A-modified mRNA (MMM) score for a PCa patient, validated by independent multi-center cohorts. Our findings revealed that differential m6A modifications were positively correlated with altered expressions of mapped m6A-modified mRNAs. Higher MMM scores were associated with shorter times to biochemical recurrence (BCR) in PCa patients, and the MMM scoring system outperformed three well-established signatures in nine independent validation cohorts, as demonstrated by Kaplan-Meier survival analysis, C-index and ROC. Patients who did not respond to androgen receptor signaling inhibitor (ARSI) therapy and immunotherapy were found to have high MMM scores. Two hub genes, TLE1 and PFKL, were confirmed to have m6A sites through MeRIP-qPCR, and their knockdown promoted PCa cell invasion. Bioinformatics analysis of single-cell databases identified cell types with high transcript abundance levels of these two genes. In summary, our study is the first to perform transcriptome-wide m6A mapping in prostate tissues. The translational potential of a prognostic signature, comprising m6A-methylated mRNAs, in predicting clinical outcomes and therapy responses for PCa patients, is demonstrated