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A ratiometric fluorescent probe based on a “dual-key-and-lock” design was reported for the imaging of vicinal dithiol proteins in living cells.

Promoted by K2CO3 (2.0 equiv), the 1,3-dipolar [3+3] cy­cloaddition between 1, 4-benzodiazepinone-based nitrones and α-halohydroxamates processed smoothly under the mild reaction conditions and delivered structurally novel and complex cis- or trans-configured d-edge heterocycle-fused 1,4-benzodiazepinones in up to >99% isolated yield with >20:1 dr. The relative configuration of the title chemical entities was clearly identified with the use of single-crystal X-ray structure analysis. The reaction mechanism was assumed to interpret the diastereoselective production of the obtained cis- or trans-configured d-edge heterocycle-fused 1,4-benzodiazepinones.

In the presence of Na2CO3, conjugate addition of α-halo hydrazones to nitroso compounds proceeded readily to give polyfunctionalized nitrones in reasonable chemical yields and excellent stereoselectivities. The chemical structure and the stereochemical configuration of the products were unambiguously identified by an X-ray single-crystal structural analysis.

Under the catalysis of PhCO2H, the 1,3-dipolar [3+2] cyclo­addition between pyrazolone-based olefins and N,N′-cyclic azomethine imines proceeded readily, thus delivering structurally novel spiropyrazolones with up to 98% yield and >20:1 dr. The relative stereochemical configuration of the obtained spiropyrazolones was unambiguously ­assigned by X-ray single-crystal structure analysis. The diastereoselective formation of the title spiropyrazolones was interpreted by the hypothesized reaction mechanism.

Under the reaction conditions of Pd(PPh3)4 (2.5 mol %) and PPh3 (10 mol %) in EtOAc at 60 °C, the formal (5 + 6) cycloaddition of vinylethylene carbonates with isatoic anhydrides proceeded smoothly and furnished medium-sized N,O-containing heterocycles in reasonable chemical yields. The chemical structures of the title products were clearly identified by X-ray diffraction analysis.

To explore new operational forecasting methods of waves, a forecasting model for wave heights at three stations in the Bohai Sea has been developed. This model is based on long short-term memory (LSTM) neural network with sea surface wind and wave heights as training samples. The prediction performance of the model is evaluated, and the error analysis shows that when using the same set of numerically predicted sea surface wind as input, the prediction error produced by the proposed LSTM model at Sta. N01 is 20%, 18% and 23% lower than the conventional numerical wave models in terms of the total root mean square error (RMSE), scatter index (SI) and mean absolute error (MAE), respectively. Particularly, for significant wave height in the range of 3–5 m, the prediction accuracy of the LSTM model is improved the most remarkably, with RMSE, SI and MAE all decreasing by 24%. It is also evident that the numbers of hidden neurons, the numbers of buoys used and the time length of training samples all have impact on the prediction accuracy. However, the prediction does not necessary improve with the increase of number of hidden neurons or number of buoys used. The experiment trained by data with the longest time length is found to perform the best overall compared to other experiments with a shorter time length for training. Overall, long short-term memory neural network was proved to be a very promising method for future development and applications in wave forecasting.

Driven by economic and social factors, more and more human beings intervene in nature to promote rapid economic and social development at the expense of ecosystem services (ES), which inevitably leads to the occurrence and even aggravation of ES trade-offs. Especially in the arid inland river basin is more serious. Therefore, this paper takes the Taolai River Basin as an example and uses the InVEST model to evaluate the spatial distribution of four typical ES, including carbon sequestration, oxygen release, windbreak and sand fixation, and water production, under the potential-actual states of the watershed. And use the Pearson correlation coefficient and the root mean square error (RMSE) to analyze the trade-off relationship between services from qualitative and quantitative aspects, respectively. Finally, the spatial matching types of trade-offs in the potential-actual states are discussed using Bivariate Local Indicators of Spatial Association, and the degree and scope of the impact of human activities on trade-offs are analyzed. The results show that the spatial distribution of the four ES has obvious heterogeneity in the potential-actual states, and the service volume of most services in the potential state is much higher than in the actual state. Secondly, there is a significant trade-offs relationship between Water production and Carbon sequestration and Oxygen release services under the potential state, while the actual state under the impact of human activities shows a significant synergistic relationship, which shows that human activities will not only increase the probability of trade-off will also increase the probability of synergy between ES. Finally, through the analysis of the meaning and causes of "high and low space dislocation" and "low and high space dislocation", it is shown that human activities will not only increase but also weaken the trade-off intensity of ES. The results of this study can provide a certain scientific basis for regional ecological environment planning and promote regional people to share ecological well-being.

In the presence of Pd2(dba)3·CHCl3 (2.5 mol%), PPh3 (10 mol%), and 60% NaH (1.5 equiv), the formal [5+3] cycloaddition between isatin-based α-(trifluoromethyl)imines and vinyloxiranes proceeded readily in 1,2-DCE at 40 ℃ and afforded cis-configured medium-heterocycle-fused spirooxindoles in the reasonable chemical yields with >20:1 dr. The relative stereochemical configuration of the title products was identified by X-ray diffraction analysis.