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2-Aminobenzothiazoles comprise a valuable structural motif, which prevails in versatile natural products and biologically active compounds. Herein, a switchable and scalable C-N coupling protocol was developed for the synthesis of these compounds from 2-chlorobenzothiazoles and primary amines. Gratifyingly, this protocol was achieved under transition-metal-free and solvent-free conditions. Moreover, introducing an appropriate amount of NaH completely switched the selectivity from mono- toward di-heteroarylation, and further investigations provided a rationale for this new finding. Furthermore, gram-scale synthesis of representative products 3a and 4a was realized by applying operationally simple and glovebox-free procedures, which revealed the practical usefulness of this work. Finally, evaluation of the quantitative green metrics provided evidence that our protocol was superior over the literature ones in terms of green chemistry and sustainability.

Herein, a wide range of mono- and di-arylated products were efficiently prepared from C–N coupling of 2-halobenzothiazoles and primary aromatic amines, and representative compounds 3b and 4b were further confirmed by X-ray crystallography. It was noteworthy that the di-arylated products, denoted as di(benzothiazolyl)amines, are new chemical entities which have not yet been reported. Moreover, the ligand-controlled protocol was extended to the synthesis of target molecules bearing a diphenyl ether or diphenyl amine scaffold. To our delight, several compounds exhibited good inhibitory activity against succinate-cytochrome c reductase (SCR), which revealed the practical application of this protocol. Notably, selective mono- and di-arylation could be switched simply by varying the ligand from Xantphos to a pyridine-functionalized N-heterocyclic carbene (NHC) ligand, and further investigations were carried out to elucidate the possible reason for this new finding.

Objective To explore the correlation between radiomic features and the pathology of pure ground-glass opacities (pGGOs), we established a radiomics model for predicting the pathological subtypes of minimally invasive adenocarcinoma (MIA) and precursor lesions. Methods: CT images of 1521 patients with lung adenocarcinoma or precursor lesions appearing as pGGOs on CT in our hospital (The Third Affiliated Hospital of Sun Yat-sen University) from January 2015 to March 2021 were analyzed retrospectively and selected based on inclusion and exclusion criteria. pGGOs were divided into an atypical adenomatous hyperplasia (AAH)/adenocarcinoma in situ (AIS) group and an MIA group. Radiomic features were extracted from the original and preprocessed images of the region of interest. ANOVA and least absolute shrinkage and selection operator feature selection algorithm were used for feature selection. Logistic regression algorithm was used to construct radiomics prediction model. Receiver operating characteristic curves were used to evaluate the classification efficiency. Results 129 pGGOs were included. 2107 radiomic features were extracted from each region of interest. 18 radiomic features were eventually selected for model construction. The area under the curve of the radiomics model was 0.884 [95% confidence interval (CI), 0.818–0.949] in the training set and 0.872 (95% CI, 0.756–0.988) in the test set, with a sensitivity of 72.73%, specificity of 88.24% and accuracy of 79.47%. The decision curve indicated that the model had a high net benefit rate. Conclusion The prediction model for pathological subtypes of MIA and precursor lesions in pGGOs demonstrated a high diagnostic accuracy. Advances in knowledge: We focused on lesions appearing as pGGOs on CT and revealed the differences in radiomic features between MIA and precursor lesions. We constructed a radiomics prediction model and improved the diagnostic accuracy for the pathology of MIA and precursor lesions.

BACKGROUND A good knowledge in wetting behavior of pesticide spray liquid on plant surface is crucial to spray applications. Difference in leaf surface wettability would result in obvious changes in spray wetting behavior. The aim of this paper is to obtain the changes of wettability during different growth periods. RESULTS The contact angle (CA) of rice leaf for each liquid increased with rice growth. No significant difference was found between cultivars. The CA was found to be correlated with the polar component of liquid surface tension. The square of the polar component was also found to be highly significant indicating that the relationship between these two properties was not a simple linear one. The surface energy of each plant surface decreased as the plants aged. This was also true of each part of the surface energy. However, no obvious difference on the proportion of the components was found among different cultivars and stages. CONCLUSIONS The changes in value of CA and surface free energy (SFE) both reflect the changes of the leaf surface wettability, while the SFE value shows better in wettability characterizing. Obvious rice leaf wettability changes were found on different development stages, which may be beneficial for researches in agrochemical sprays wetting and spreading behavior. Factors influencing these alterations were discussed. © 2013 Society of Chemical Industry

In order to improve long-term durability of bioprosthetic heart valve, we take the spherical,paraboloidal,cylindrical and the ellipsoidal leaflets for nonlinear analysis and the material is orthotropic.The experimental results of the finite element nonlinear analysis show that when the leaflets with the material orthotropic is closed,the deformation of the symmetric edge is larger than else. The stress distribution of the cylindrical, spherical, paraboloidal and ellipsoidal valve leaflets is quite different. The ellipsoidal valve leaflets have more advantages than the cylindrical, spherical, paraboloidal valve leaflets.This work is very helpful to manufacture reasonable shaped valvular leaflets and to prolong the lifetime of the bioprosthetic heart valve.

Using a simplified in-situ process, we have successfully generated relatively long IF WS2 nanotubes, in good yield and purity. The nanotubes are formed directly from WOx nanorods created from W and SiO2 during the first stage. Structural similarities and differences between IF nanotubes and carbon nanotubes have been analyzed. A noteworthy feature of the WS2 tubes is that some of their tips are fully open.

A good knowledge in wetting behavior of pesticide spray liquid on plant surface is crucial to spray applications. Difference in leaf surface wettability would result in obvious changes in spray wetting behavior. The aim of this paper is to obtain the changes of wettability during different growth periods.The contact angle (CA) of rice leaf for each liquid increased with rice growth. No significant difference was found between cultivars. The CA was found to be correlated with the polar component of liquid surface tension. The square of the polar component was also found to be highly significant indicating that the relationship between these two properties was not a simple linear one. The surface energy of each plant surface decreased as the plants aged. This was also true of each part of the surface energy. However, no obvious difference on the proportion of the components was found among different cultivars and stages.The changes in value of CA and surface free energy (SFE) both reflect the changes of the leaf surface wettability, while the SFE value shows better in wettability characterizing. Obvious rice leaf wettability changes were found on different development stages, which may be beneficial for researches in agrochemical sprays wetting and spreading behavior. Factors influencing these alterations were discussed.