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Four new 2D SOFs were formed by utilizing multi-type cucurbit[n]urils with a rod-like bipyridine ligands, realizing fluorescent conversion in the solid state.

A symmetric organic dye can form a highly stable homotrimer in the cavity of CB[10], which exhibits unique multicolour fluorescence different from that of the single molecule or its dimer.

A porous supramolecular framework has been for the first time revealed to undergo interpenetration in crystal and non-interpenetration in solution. A new supramolecular organic framework Bu-SOF has been constructed from the co-assembly of a tetracationic tetrahedral monomer and cucurbit[8]uril (CB[8]) in water through the encapsulation of two anti-parallel n-butyl chains by CB[8]. X-ray diffraction analysis reveals that Bu-SOF forms 3-fold interpenetrated networks in crystals grown by evaporation of its solution in water. 1H NMR, dynamic light scattering and isothermal titration calorimetric experiments confirm that Bu-SOF is also formed in water. Solid samples, prepared by lyophilizing the aqueous solution of Bu-SOF, can adsorb nanoscaled organic dyes, supporting the porosity of the framework and thus non-interpenetration in solution. The avoidance of interpenetration of Bu-SOF in solution has been attributed to the filling of water inside the porous framework as well as the electrostatic repulsion of the appended bipyridinium units of the tetrahedral building block.

Hand, foot and mouth disease (HFMD) is a widespread infectious disease that causes a significant disease burden on society. To achieve early intervention and to prevent outbreaks of disease, we propose a novel warning model that can accurately predict the incidence of HFMD.We propose a spatial-temporal graph convolutional network (STGCN) that combines spatial factors for surrounding cities with historical incidence over a certain time period to predict the future occurrence of HFMD in Guangdong and Shandong between 2011 and 2019. The 2011-2018 data served as the training and verification set, while data from 2019 served as the prediction set. Six important parameters were selected and verified in this model and the deviation was displayed by the root mean square error and the mean absolute error.As the first application using a STGCN for disease forecasting, we succeeded in accurately predicting the incidence of HFMD over a 12-week period at the prefecture level, especially for cities of significant concern.This model provides a novel approach for infectious disease prediction and may help health administrative departments implement effective control measures up to 3 months in advance, which may significantly reduce the morbidity associated with HFMD in the future.

A highly efficient and selective carbon–carbon double bonds cleavage of styrene compounds involving molecular oxygen was achieved using TBHP as a free radical initiator in diethylene glycol diethyl ether medium. Various styrene compounds, such as phenyl acrylic acids and its esters, 2-substituted 3-phenyl acrylic acids and its esters, chalcones, 4-phenyl-3-buten-2-one and bis(2-phenylvinyl) ketone, 5-benzylidene-1,3-dimethyl-pyrimidine-2,4,6-triones, could be effectively oxidized into the corresponding aryl carbonyl compounds, and the yield was up to 99%. A suitable mechanism was proposed. Gram-level synthesis further illustrated the practicality of our method.

p-Nitrobenzoic acid could be efficiently prepared from aerobic oxidation ofp-nitrotoluene using manganese dioxide (MnO2) andN-hydroxyphthalimide (NHPI) as catalysts. The conditions of oxidation were also optimaized: 97 % conversion ofp-nitrotoluene and 89 % isolated yield ofp-nitrobenzoic acid could be obtained at 110 °C under 0.4 MPa for 4 h in presence of 10 mol% NHPI and 10 mol% MnO2.

Manganese oxides, which are easily prepared, simple to use and capable of being recycled, have been employed as catalyst in the selective oxidation of toluene to benzoic acid for the first time. Molecular oxygen was used as oxidant under additive- and solvent-free conditions. As a result, 39% conversion of toluene and 93% selectivity of benzoic acid were achieved.

A high-yield synthesis of p-hydroxybenzaldehyde from p-cresol and molecular oxygen was achieved over a CuMn-oxide supported carbon catalyst. The reaction parameters such as pressure, stirring speed, reaction temperature, solvent, and the amount of sodium hydroxide in the reaction media were optimized. As a result, a high conversion of p-cresol (99%) and a high selectivity to p-hydroxybenzaldehyde (96%) were realized at the same time. Catalyst separation and recycling tests clearly showed that the reaction proceeded on the heterogeneous catalyst but not on dissolved species.

In this paper, a new approach of segmenting cine coronary angiography is proposed. Rather than treating each frame of a video sequence individually and applying the segmentation on them separately, our approach tackles the segmentation of all the frames as a whole via incorporating the prior knowledge that the background components in all frames have much strong correlation mutually than vessels do, so our approach is global in the time dimension. We have applied this approach to the segmentation of clinical data and obtain encouraging result.

The reaction mass spectrometry of cyclic glycols and monosaccharides with methylene chloride as reagent was studied. In the presence of ammonia, it was found that methylene chloride reacted stereoselectively with the quasi-molecular ions of cyclic glycols and monosaccharides to form characteristic ions, by comparison of the relative abundances of which the stereoisomers of cyclopentane-l,2-diols and cyclohexane-l,2-diols and some monosaccharides could be definitely distinguished.

Copper ions adsorption by beer yeast was studied by AAS, FTIR, SEM/EDS etc. The quantity of copper biosorption by NaOH-treated yeast and acetone-treated yeast increased significantly, while the esterification of carboxylate functionalities and the methylation of amino group presented in the cell walls of yeast resulted in a marked decrease in copper adsorption. These results show that amino and carboxylate groups in yeast cell wall play a great role in binding copper. According to IR spectra, the dominating bands near 1 652, 1 539 and 1 237 cm(-1) are assigned to amide I , amide II and amide IlI, the characteristic IR absorption of protein which could be one of the significant components of cell walls. The peak near 1 456 cm(-1) is attributable to the bending stretching of CH2- and CH3-. The changes in the spectra of the copper-exposed yeast biomass were in the stretch of hydroxyl groups or amino groups, which shifted from 3 392 to 3 404 cm' , and in the symmetrical stretch of carboxylate groups, which shifted from 1 405 to 1 383 cm(-1). The components and structure of the exposed-copper biomass remain intact. SEM/EDS analysis shows that the main elements of beer yeast are carbon, oxygen, and magnesium, while the surface of yeast is rough, and the copper-loaded yeast only binds little copper.

The chemical ionization (CI) mass spectrometry of fumaric and maleic acids and their esters with methylene chloride as reagent gas is described. The introduction of methylene chloride to the CI(CH 4 ) plasma led to the formation of new characteristic ions in addition to the protonation and the subsequent fragmentation, revealing diagnostic information on the configuration of geometrical isomers. The new characteristic ions have been found to arise from the addition of the reactant ion of methylene chloride, [CH 2 CI] + , to the substrates and, for higher dialkyl esters, from the further McLafferty rearrangement of the addudt ion [M+CH 2 CI] +

Copper and manganese were found to be two concordant partners in the synthesis of p-hydroxybenzaldehyde from p-cresol; under mild conditions, this research realised 95.6% selectivity for p-hydroxybenzaldehyde at 98.5% conversion of p-cresol.