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As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection posed a significant threat to public health and the global economy, in vitro diagnosis of the SARS-CoV-2 nucleocapsid protein proved to be an effective way for SARS-CoV-2 infection control in the past years. Tyramide signal amplification (TSA) has been extensively utilized in tissue imaging and pathological diagnosis owing to the powerful signal enhancement. However, the elevated “ALWAYS ON” fluorescence background limited the accuracy and sensitivity of the conventional TSA assay. To achieve an activated “TURN ON” signal, herein, a small molecule, termed dichlorodihydrofluorescein tyramide (T-DCFH), was synthesized for activatable TSA. Under the catalysis of horseradish peroxidase (HRP) with hydrogen peroxide (H2O2), this T-DCFH facilitates the “TURN ON” fluorescence signal. Additionally, as a recognition tool, DNA aptamer has been used for developing in vitro diagnostic approaches. Hence, based on HRP-labeled aptamers binding with SARS-CoV-2 nucleocapsid protein, we achieved aptamers-based activatable TSA detection with a higher signal-to-noise ratio than that of fluorescent dye (FITC)-labeled aptamers, while showing lower background than traditional fluorescein tyramide with “ALWAYS ON”. The results demonstrated that the activated T-DCFH significantly enhances the fluorescence signal while diminishing the background noise. By employing multiple aptamers targeting, we offered a timely and accurate in vitro diagnostic approach for future emergent infectious diseases.

A novel thrust control method based on inverse control is proposed to improve engine response ability. The On Line Sliding Window Deep Neural Network (OL SW DNN) is proposed and adopted as inverse mapping model modeling method of inverse control. The OL SW DNN has deeper layer structure, which makes the inverse mapping model have stronger fitting capacity for nonlinear object than traditional NN. Moreover, due to adopt on-line learning modeling method, the proposed adaptive control method can obtain desired thrust whether engine degrades or not. The comparison simulations of the traditional control method based on PID and the proposed control method are carried out. Compared with the traditional control method, the proposed control method can obtain desired thrust when the engine degradation occurs, but also has fast response ability (the acceleration times for engine thrust increase to 95 % thrust of acceleration object decreases by 1.35 seconds).

In order to reach a compromise between fast response control and torques matching control in double turboshaft engines, research on nonlinear model predictive control for turboshaft engines based on double engines torques matching is conducted. Meanwhile, a Nonlinear Model Predictive Control (NMPC) method is proposed, which combines the control index of the power turbine speed with torques matching of double engines creatively. In addition to the control index, the difference of output torques between each engine is also incorporated in the objective function as a penalty term to ensure constant speed control and short torques matching time. Simulation results demonstrate that relative to unilateral torques matching, the settling time of the bidirectional matching method can be reduced by nearly 30.8%. Nevertheless, compared with the bidirectional torques matching method under the cascade PID controller, the NMPC method can decrease the overshoot of the power turbine speed by 65% and reduce the matching time by 15.5% synchronously. Besides fast response control of turboshaft engines, fast torques matching control of double engines is accomplished as well.

The occurrences and spatial distributions of eight organic ultraviolet absorbents (UVAs) were investigated in surface sediments from Taihu Lake, China. The detection frequencies and concentrations of UVAs in 2016 were significantly higher than those in 2015.2-Ethylhexyl methoxycinnamate and homosalate (HMS) were the predominant UVAs in the sediment samples. The total UVA concentration range in sediment samples was 0.15–85.3 ng/g. The spatial distribution results showed that UVAs were concentrated in the northwest of Taihu Lake. The total organic carbon content may affect the fate of UVAs in sediments. Source analysis and correlation analysis showed that the following compounds had high proportions and significant correlations: 2-ethylhexyl methoxycinnamate, ethylhexyl salicylate, and HMS in 2015; and benzophenone-3, HMS, and benzyl salicylate in 2016. These results indicated the correlated compounds within each year had the same source. Ecological risk assessment results showed that UVAs in sediment from Taihu Lake may present a moderate risk to benthic organisms. The risk quotient of UVAs in 2016 was slightly higher than that in 2015. The seasonal pollution characteristics of UVAs and their comprehensive environmental risks should receive further attention.