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Sensitive detection of miRNA targets in complex biological samples possesses great value in biopsy analysis and disease diagnosis but is still challenging because of low abundance and nonspecific interferences. In this work, self-primer DNA polymerization-propelled stochastic walkers (SWs) were proposed to detect miRNA-24 by combining magnetic microbeads (MMBs) and flow cytometry. The MMBs not only provide a three-dimensional interface for DNA walkers but also facilitate the enrichment and isolation of RNA targets from complex biological samples such as serum. The SWs can be initiated to walk through the entire surface of MMBs and transduce RNA walking into amplified fluorescence signals, with the detection limit of miRNA-24 at 0.95 pM. Moreover, this strategy integrating with flow cytometry was demonstrated to have good specificity with other homologous miRNAs. This platform offers promising applications in RNA biosensing and biomedical diagnostics.

Recent years have witnessed emerging oscillation stability issues in DC microgrid via power electronic converters. Considering the confidentiality of the parameters and structure of power electronic devices, the impedance method is widely used to study the small signal stability. However, the stability assessment based on traditional impedance model and Gershgorin Theorem have some shortcomings for multiple converters DC microgrid. This may lead to the problem that the stability analysis results are not accurate enough or the criteria cannot be applied. In this article, the system is modeled as a medium and high dimensional negative feedback system. Further, a sufficient stability criterion based on extended Gershgorin Theorem is developed through reshaping the range of eigenvalues estimation for the non-diagonal advantage system. Finally, the validity of the criterion is verified by a 6 converters system. Test results indicate the proposed method has the potential to assess the high-order system stability with low computational complexity. Moreover, its low conservatism as a sufficient criterion is helpful to guide the system design.

The collector fields of large-scale commercial trough solar power stations often face inhomogeneities in environmental parameters and resistance to flow in the pipe network. Aiming at dealing with the problem of uneven distribution of hydraulic parameters and radiation in large collector fields, this study establishes a heat transfer model and a hydraulic model of the collector field and proposes a control strategy for the heat transfer fluid (HTF) flow in the parabolic trough collector (PTC) loops. Based on the proposed hydraulic model, the loop valve opening is directly calculated and fast control of the loop HTF flow is achieved. Simulation results show that the scheme significantly reduces the differences in HTF temperature at the outlet of the PTC loops.

Docetaxel (DTX) treatment effectively prolongs the overall survival of patients with prostate cancer. However, most patients eventually develop resistance to chemotherapy and experience tumor progression or even death. Long noncoding RNAs (lncRNAs) affect docetaxel chemosensitivity. However, the biological role and regulatory mechanisms of lncRNAs in docetaxel-resistant prostate cancer remain unclear. Differences in lncRNAs were evaluated by lncRNA sequencing and evaluated using quantitative real-time polymerase chain reaction, and TrkB expression was measured through western blot analysis. Proliferation was measured using the MTS, while apoptosis and cell cycle were measured using flow cytometry. In addition, migration and invasion were measured using transwell assays. Forty-eight female BALB/c nude mice were used for subcutaneous tumorigenicity and lung metastasis assays. We found that LINC01963 was overexpressed in the PC3-DR cells. LINC01963 silencing enhanced the chemosensitivity of PC3-DR to docetaxel and inhibited tumorigenicity and lung metastasis, while LINC01963 overexpression enhanced the chemoresistance of PC3 cells to docetaxel. It was found that LINC01963 bind to miR-216b-5p. The miR-216b-5p inhibitor reversed the suppressive effect of sh-LINC01963 on PC3-DR cell proliferation, migration, and invasion. Furthermore, miR-216b-5p can bind to the 3′-UTR of NTRK2 and inhibit TrkB protein levels. TrkB enhances docetaxel resistance in prostate cancer and reverses the effects of LINC01963 silencing and miR-216b-5p overexpression. In conclusion, silencing LINC01963 inhibited TrkB protein level to enhance the chemosensitivity of PC3-DR to docetaxel by means of competitively binding to miR-216b-5p. This study illustrates that LINC01963 is a novel therapeutic target for treating prostate cancer patients with DTX resistance.

Base promoted [4+3] annulation of trifluoromethylpyrazole(TFPZ) derived α,β‐unsaturated ketones with crotonate‐derived sulfur ylides provided a diverse set of CF3‐containing oxepino[2,3‐c]pyrazole motif in good to excellent yields through a simple, mild and fast manner. Significantly, one‐pot strategy could be successfully applied to this transformation from available materials. Also, the utility of our versatile protocol was further demonstrated by gram‐scale reaction and useful derivation. A diverse set of CF3‐containing oxepino[2,3‐c]pyrazoleswere obtained through direct [4+3] annulation or one‐pot strategy based on trifluoromethylpyrazole(TFPZ) derived α,β‐unsaturated ketones.

The feasibility of the application of terahertz electromagnetic waves in the diagnosis of prostate cancer was examined. Four samples of incomplete cancerous prostatic paraffin-embedded tissues were examined using terahertz spectral imaging (TPI) system and the results obtained by comparing the absorption coefficient and refractive index of prostate tumor, normal prostate tissue and smooth muscle from one of the paraffin tissue masses examined were reported. Three hundred and sixty cases of absorption coefficients from one of the paraffin tissues examined were used as raw data to classify these three tissues using the Principal Component Analysis (PCA) and Least Squares Support Vector Machine (LS-SVM). An excellent classification with an accuracy of 92.22% in the prediction set was achieved. Using the distribution information of THz reflection signal intensity from sample surface and absorption coefficient of the sample, an attempt was made to use the TPI system to identify the boundaries of the different tissues involved (prostate tumors, normal and smooth muscles). The location of three identified regions in the terahertz images (frequency domain slice absorption coefficient imaging, 1.2 THz) were compared with those obtained from the histopathologic examination. The tissue tumor region had a distinctively visible color and could well be distinguished from other tissue regions in terahertz images. Results indicate that a THz spectroscopy imaging system can be efficiently used in conjunction with the proposed advanced computer-based mathematical analysis method to identify tumor regions in the paraffin tissue mass of prostate cancer.

Accurate forecasting of load and renewable energy sources (RES) is crucial in the configuration of an energy system. However, uncertainties of these variables present a challenge when making decisions regarding the energy system. To address this challenge, this paper proposes an ensemble interpretable uncertainty forecasting framework called En-IENN, based on an Interpretable Neural Network (INN) and an improved Evidential Neural Network (IENN). The raw features are initially filtered by INN and subsequently utilized as inputs for IENN to forecast the uncertainty. INN clearly explains the reasons for feature selection, and ultimately, the evidential distribution is determined by minimizing an improved loss function of ENN. In comparison with other feature selection and uncertainty forecasting methods, En-IENN is demonstrated to be more interpretable and reliable. After that, utilizing the predicted load and RES, a battery capacity configuration in a virtual power plant is simulated to demonstrate the effectiveness of En-IENN. By comparing the configuration under different prediction intervals of loads and RES, the En-IENN is proven to be superior to other prediction methods.

During the scram or load rejection of nuclear power plant, the excess steam of steam generator needs to be dumped to the main condenser through the steam conditioning device to reduce the temperature rising of the primary loop and prevent the steam generator from over-pressure. For study of the dynamics and control strategy of the steam dump system, this paper established a simulation model of nuclear power plant using Gsuite simulation platform, and then studied the dynamical-varying of some important-variables in nuclear power plants during scram. The results indicated that the model built can approximately predict the dynamic changes of important parameters such as the average temperature of the primary loop and the main steam pressure. Therefrom it is concluded that the joint operation of the steam dump system and atmospheric steam dump system can effectively prevent the rising of the temperature of the primary loop and the overpressure of the secondary circuit, and thus it can avoid the opening of the main-steam safety valve.

Purpose Helical coil electromagnetic launchers (HEMLs) using motion-induced commutation strategy solve the problem of synchronization control perfectly. HEMLs can meet the requirements of multiple applications such as the electromagnetic catapult, electromagnetic mortar and high-velocity coilgun. The trade-off between the velocity and efficiency is an important basis for these different applications. To optimize such objectives before actual design, the purpose of this paper is to focus on the efficient and flexible calculation model and algorithm. A novel structure of HEML is proposed after the transient simulation by this algorithm, which can improve the energy conversion efficiency and suppress the muzzle arc without affecting the velocity too much.Design/methodology/approach The equivalent circuit model of the launcher is established and the governing equations are derived. A combination of the four-stage Runge–Kutta method and the trapezoidal quadrature formula are used to solve the governing equations.Findings With smaller number of turns in the coils of HEML, the velocity is larger and the efficiency is lower. The non-uniform HEML is an effective option to improve the energy conversion efficiency and to suppress the muzzle arc with almost the same muzzle velocity as the conventional HEML.Originality/value The paper presents a common model and a flexible fast numerical method which can be used in multi-objective optimization of HEMLs such as the genetic algorithm. A new structure of the non-uniform HEML is proposed to improve the energy conversion efficiency and to suppress the muzzle arc of the launcher. [ABSTRACT FROM AUTHOR]

Bearing failure is one of the most important causes of breakdown of rotating machinery. These failures can lead to catastrophic disasters or result in costly downtime. One of the key problems in bearing fault diagnosis is to detect the bearing fault as early as possible. This capability enables the operator to have enough time to do some preventive maintenance. Most papers investigate the bearing faults under rational assumption that bearings work individually. However, bearings are usually working as a part of complex systems like a gearbox. The fault signal of bearings can be easily masked by other vibration generated from gears and shafts. The proposed method separates bearing signals from other signals, and then the optimum frequency band which the bearing fault signal is prominent is determined by mean envelope Kurtosis. Subsequently, the envelope analysis is used to detect the bearing faults. Finally, two bearing fault experiments are used to validate the proposed method. Each experiment contains two bearing fault modes, inner race fault and outer race fault. The results demonstrate that the proposed method can detect the bearing fault easier than spectral Kurtosis and envelope Kurtosis.

Abstract: The dispersion of V2O5 in V2O5/TiO2 catalysis has been studied by x-ray photoelectron spectroscopy, transmission electron microscopy and a thermal gravimetric analysis for samples with various V2O5 content. The coverage, thickness and dispersion of vanadium oxide were calculated by a quantitative x-ray photoelectron spectroscopy (XPS) analysis. The experimental results show that V2O5 is well dispersed on a TiO2 surface at low VEOs content. The coverage increases rapidly with the V2O5 content up to 10 wt%. Beyond that, the coverage increases very slowly, and considerable parts of the TiO2 surface remain bare even at a V2O5 content as high as 40 wt%. The vanadium oxide is probably present on the TiO2 surface as isolated patches or islands. This investigation shows that x-ray photoelectron spectroscopy is also a powerful tool for obtaining information about the dispersion of supported species in catalytic research.

The dispersion of VO in VO/TiO catalysis has been studied by x-ray photoelectron spectroscopy, transmission electron microscopy and a thermal gravimetric analysis for samples with various VO content. The coverage, thickness and dispersion of vanadium oxide were calculated by a quantitative x-ray photoelectron spectroscopy (XPS) analysis. The experimental results show that VO is well dispersed on a TiO surface at low VEOs content. The coverage increases rapidly with the VO content up to 10 wt%. Beyond that, the coverage increases very slowly, and considerable parts of the TiO surface remain bare even at a VO content as high as 40 wt%. The vanadium oxide is probably present on the TiO surface as isolated patches or islands. This investigation shows that x-ray photoelectron spectroscopy is also a powerful tool for obtaining information about the dispersion of supported species in catalytic research. [ABSTRACT FROM AUTHOR]