Fault Diagnosis Method for Rolling Bearings Based on Grey Relation Degree.

Aiming at the difficult problem of extracting fault characteristics and the low accuracy of fault diagnosis throughout the full life cycle of rolling bearings, a fault diagnosis method for rolling bearings based on grey relation degree is proposed in this paper. Firstly, the subtraction-average-based optimizer is used to optimize the parameters of the variational mode decomposition algorithm. Secondly, the vibration signals of bearings are decomposed by using the optimized results, and the feature vector of the intrinsic mode function component corresponding to the minimum envelope entropy is extracted. Finally, the grey proximity and similarity relation degree based on standard distance entropy are weighted to calculate the grey comprehensive relation degree between the feature vector of vibration signals and each standard state. By comparing the results, the diagnosis of different fault states and degrees of rolling bearings is realized. The XJTU-SY dataset was used for experimentation, and the results show that the proposed method achieves a diagnostic accuracy of 95.24% and has better diagnosis performance compared to various algorithms. It provides a reference for the fault diagnosis of rolling bearings throughout the full life cycle.

Layered energy-saving speed planning and control method for electric vehicle on continuous signal lights road.

Emergency start-stop in front of signal lights is one of the main reasons for additional energy consumption and ride discomfort of Electric Vehicle (EV). Existing research on this issue rarely takes into account both energy consumption and ride comfort. Therefore, the layered energy-saving speed planning and control method is proposed. The upper is the layer of energy-saving speed planning. This layer reduces energy consumption of EV by reducing the number of stops on continuous signal lights road and minimizing the range of speed change. On this basis, the sinusoidal variable speed curve is used to smooth the acceleration process to improve ride comfort. Finally, the energy-saving speed considering ride comfort is obtained. This layer makes up for the issue that existing research rarely takes into account both energy consumption and ride comfort of EV, and is an extension and innovation of existing research. The lower is the layer of Model Predictive Controller (MPC)-based speed control. Based on the longitudinal dynamics model of EV, the MPC-based speed controller is established to control EV to track the energy-saving speed. The controller is easy to understand and implement, and it is also suitable for other research on EV, which has certain application value. The simulation results show that under various working conditions, the maximum energy consumption of EV passing through continuous signal lights road without stopping is 604.29 kJ/km, and the minimum is 244.76 kJ/km. The energy consumption is lower than that of actual road test, and it can be saved by 23.18 % compared with the method in the same field. The maximum Root Mean Square of accelerations (RMSa) is 0.25 m/s2, and the minimum is 0.10 m/s2. The values of RMSa above are lower than 0.315 m/s2, which indicates that the ride comfort is good. The utilized method can reduce energy consumption of EV, improve its range and ride comfort, which has important reference significance for promoting the development of EV.

Screening of Estrogenic-Disrupting Compounds in Dairy Products Based on the Estrogen Receptor Cocktail.

The residue of estrogenic-disrupting compounds (EDCs) that are secreted by cows, added as drugs, and present in the feed may exist in dairy products. A gold nanoparticles (AuNPs)-estrogen receptor (ER) cocktail colorimetric assay equipped with ER cocktail solid phase extraction (SPE) was established to screen EDCs. Nine EDCs with high, moderate, and low estrogenic activity were selected to be the representative targets. The recognition range of the colorimetric assay combined with the ER cocktail SPE was wider than that of a single ERα or ERß. The lowest detection limit of the established assay was about 10-9 mg·mL-1. The detection limits of estrone, bisphenol A, and bisphenol B were about one order of magnitude lower than the method based on a single ER. The recoveries of the spiked nine EDCs were between 80.0% and 110.0%, and daidzein was identified in the dairy product. The developed method has potential application prospects in food safety and environmental monitoring.

Electrochemical Cell-Based Sensor for Detection of Food Hazards.

People's health has been threatened by several common food hazards. Thus, it is very important to establish rapid and accurate methods to detect food hazards. In recent years, biosensors have inspired developments because of their specificity and sensitivity, short reaction time, low cost, small size and easy operation. Owing to their high precision and non-destructive characteristics, cell-based electrochemical detection methods can reflect the damage of food hazards to organisms better. In this review, the characteristics of electrochemical cell-based biosensors and their applications in the detection of common hazards in food are reviewed. The strategies of cell immobilization and 3D culture on electrodes are discussed. The current limitations and further development prospects of cell-based electrochemical biosensors are also evaluated.

A solid-phase extraction method for estrogenic disrupting compounds based on the estrogen response element.

A solid-phase extraction (SPE) method for enriching and purifying estrogenic disrupting compounds (EDCs) based on the estrogen response element was established. The estrogen receptor was used for molecular recognition, as it specifically binds EDCs. An estrogen response element was used to maintain the activity of the estrogen receptor. High-performance liquid chromatography (HPLC) was used to quantify the EDCs. This method combined with HPLC was applied to detect three kinds of EDCs, such as bisphenol A (BPA), 17ß-estradiol, and diethylstilbestrol in a liquid milk matrix, with recoveries of 84.1 ± 8.2% to 113.6 ± 2.9%. The limits of detection and quantification of the established method were 1 × 10-6 mg·mL-1 and 5 × 10-6 mg·mL-1. The method was further applied to analyze market samples, including liquid milk, fermented milk, and milk powder. Only BPA was detected from one brand of liquid milk and it was below the regulatory level.

Insulin negatively regulates dedifferentiation of mouse adipocytes in vitro.

Insulin plays an important role during adipogenic differentiation of animal preadipocytes and the maintenance of mature phenotypes. However, its role and mechanism in dedifferentiation of adipocyte remains unclear. This study investigated the effects of insulin on dedifferentiation of mice adipocytes, and the potential mechanisms. The preadipocytes were isolated from the subcutaneous white adipose tissue of wild type (WT), TNFα gene mutant (TNFα-/-), leptin gene spontaneous point mutant (db/db) and TNFα-/-/db/db mice and were then induced for differentiation. Interestingly, dedifferentiation of these adipocytes occurred once removing exogenous insulin from the adipogenic medium. As characteristics of dedifferentiation of the adipocytes, downregulation of adipogenic markers, upregulation of stemness markers and loss of intracellular lipids were observed from the four genotypes. Notably, dedifferentiation was occurring earlier if the insulin signal was blocked. These dedifferentiated cells regained the potentials of the stem cell-like characteristics. There is no significant difference in the characteristics of the dedifferentiation between the adipocytes. Overall, the study provided evidence that insulin plays a negative regulatory role in the dedifferentiation of adipocytes. We also confirmed that both dedifferentiation of mouse adipocytes, and effect of the insulin on this process were independent of the cell genotypes, while it is a widespread phenomenon in the adipocytes.

Analysis of Biomolecules Based on the Surface Enhanced Raman Spectroscopy.

Analyzing biomolecules is essential for disease diagnostics, food safety inspection, environmental monitoring and pharmaceutical development. Surface-enhanced Raman spectroscopy (SERS) is a powerful tool for detecting biomolecules due to its high sensitivity, rapidness and specificity in identifying molecular structures. This review focuses on the SERS analysis of biomolecules originated from humans, animals, plants and microorganisms, combined with nanomaterials as SERS substrates and nanotags. Recent advances in SERS detection of target molecules were summarized with different detection strategies including label-free and label-mediated types. This comprehensive and critical summary of SERS analysis of biomolecules might help researchers from different scientific backgrounds spark new ideas and proposals.

In Vivo Capture of Circulating Tumor Cells Based on Transfusion with a Vein Indwelling Needle.

Detection of circulating tumor cells (CTCs) could be used as a "liquid biopsy" for tracking the spread of cancer. In vitro detection methods based on blood sampling and in vitro CTC capture often suffer from the small sampling volume and sampling error. Here, the in vivo capture of CTCs based on transfusion with a surface-modified vein indwelling needle is proposed. When the needle was applied to transfusion in the vein, the simultaneous capture of CTCs was performed. To investigate the actual capture efficiency of the in vivo capture method, labeled MCF-7 cells were directly injected into the veins of rabbits, wild type mice, and nude mice and could be successfully captured. Two of 5 MCF-7 cells injected into the veins of nude mice were successfully captured. To investigate the CTC capture of mouse tumor model and compare with the in vitro method, mice were subcutaneous inoculated with metastatic 4T1 cells. Seven and 21 days after inoculation, CTCs were captured for the first time using in vivo and in vitro methods, respectively. This predicted that the in vivo method could be more suitable for use of early diagnosis of cancer than the in vitro method. As CTC capture can be performed at the same time as transfusion and does not cause further bodily harm, it would be easily accepted by patients. This efficient, simple, and less damaging method involving the use of a vein indwelling needle could be popularized easily in the clinic.

Validation and comparative studies of four sulfonamide immunoassays based on the same generic polyclonal antibody.

Four different immunoassays based on the same generic polyclonal antibody were validated by high performance liquid chromatography, respectively. They also were compared with each other in terms of sensitivity, precision, and accuracy for the quantification or screening of sulfonamide residues in food samples. Correlation studies showed that there was a good correlation between the immunoassays and liquid chromatography data. The conventional plate assay has better precision and the plate-enhanced chemiluminescent assay has higher sensitivity. These two methods all could be used as quantification methods for large numbers of samples and complements of the conventional analytical methods in laboratory. The flow-through strip assay has higher sensitivity and the dip-stick strip assay was less affected by matrix effect. These two methods all could be used as valuable tools for the rapid on-site screening of sulfonamide residues in animal-derived food samples.

Determination of nine organophosphorus pesticides in cereals and kidney beans by capillary gas chromatography with flame photometric detection.

A method is developed for the determination of nine organophosphorus pesticide residues in cereals and kidney beans by capillary gas chromatography with flame-photometric detection. In this method, dichloromethane is used for clean-up after liquid-liquid extraction. It is shown that good separations are obtained using a fused-silica capillary column (DB-1701) by the optimized temperature program. In the spiked levels of 0.012-0.43 mg/kg, the recoveries are from 83.7% to 107%, with the relative standard deviation between 3.2% and 13% and limits of detection from 8.2 to 15 microg/kg. The method is rapid, sensitive, and practical.