A supramolecular gel was constructed by using an imidazolium-based surfactant, N-cetyl-N'-carboxymethyl imidazolium bromide ([N-C16, N'-CO2H-Im]Br), in the DMSO/H2O binary solvent mixtures and investigated as an adsorbent for removing dyes from aqueous solution. The self-assembled gel displays a morphology of microplatelets stacked in bilayer units with interdigitated hydrocarbon tails, and the structure remains unchanged below the sol-gel transition temperature. The gel also exhibits a strong birefringence property and excellent mechanical strength. In particular, the gels show superior performance in removal of anionic dye molecules, for example, removing 80% of eosin Y within 10 min, The constructed gels also present excellent salinity tolerance, even when the concentration of NaCl is 1000 times higher than that of the dye, and can maintain their high efficiency after 25 cycles, indicative of their promise in water treatment.

It is commonly considered that amyloid-b (Ab) fibrils are heavily involved in the neurological diseases. Establishing an external model based on the core recognition motif (diphenylalanine, FF) of Ab would be of significance in understanding the assembly and disassembly of Ab fibrils in living system. Herein, supramolecular gels with structure transition from amyloid-like b-sheet to different supramolecular helices were obtained through the co-assembly of a Nfluorenylmethoxycarbonyl-protected L-FF (L-FmocFF) with achiral pyridine derivatives. It is found that the different stacking modes (H-or J-aggregates) of additives and the microenvironment of chiral carbon play vital roles for the selectively chiral transfer or amplification of L-FmocFF. The dynamic process of helix formation was also captured. This work provides a convenient co-assembly way to explore the structure basis of Ab fibrils with a controlled chirality.

The spherical Lindquist type polyoxometalate, Mo(6)O(19)(2)(-), has been used as a noncoordinating anionic template for the construction of novel three-dimensional lanthanide-aromatic monocarboxylate dimer supramolecular networks [Ln(2)(DNBA)(4)(DMF)(8)][Mo(6)O(19)] (Ln = La 1, Ce 2, and Eu 3, DNBA = 3,5-dinitrobenzoate, DMF = dimethylformamide). The title compounds are characterized by elemental analyses, IR, and single-crystal X-ray diffractions. X-ray diffraction experiments reveal that two Ln(III) ions are bridged by four 3,5-dinitrobenzoate anions as asymmetrically bridging ligands, leading to dimeric cores, [Ln(2)(DNBA)(4)(DMF)(8)](2+); [Ln(2)(DNBA)(4)(DMF)(8)](2+) groups are joined together by pi-pi stacking interactions between the aromatic groups to form a two-dimensional grid-like network; the 2-D supramolecular layers are further extended into 3-D supramolecular networks with 1-D box-like channels by hydrogen-bonding interactions, in which hexamolybdate polyanions reside. The compounds represent the first examples of 3-D carboxylate-bridged lanthanide dimer supramolecular "host" networks formed by pi-pi stacking and hydrogen-bonding interactions encapsulating noncoordinating "guest" polyoxoanion species. The fluorescent activity of compound 3 is reported.

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Multi-stimuli responsive materials have attracted intense attention as extensive application prospect in many fields, yet achievement of multi-stimuli responsiveness remains a challenge. Herein, we report a tri-stimuli responsive supramolecular structure fabricated by a cationic surfactant, 4-ethyl-4'-(trimethylaminohexyloxy) azobenzene bromide (ETAB), and anionic Eu-containing polyoxometalates (Eu-POM), based on an ionic self-assembly (ISA) strategy. Following different responsive mechanisms, the resultant ETAB/Eu-POM supramolecular materials are responsive to UV light, pH, and Cu(2+), respectively. The response to UV irradiation is based on the configuration change of azobenzene molecules. The response to H(+) can be attributed to the formation of a hydrogen bond W-O···H···O-H among Eu-POM, H(+), and H2O, which blocks the energy transfer pathway from O → W, while the coordination interaction between Cu(2+) and Oc (bridged oxygen of two octahedra sharing an edge in the Eu-POM molecule) causes the response to Cu(2+). The multi-stimuli responsive characteristics for the ETAB/Eu-POM supramolecular structures maybe provide a potential application in ultraviolet detection, optical storage devices, and chemical substance sensors, etc.

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Background: This study is to distinguish peripheral lung cancer and pulmonary inflammatory pseudotumor using CT-radiomics features extracted from PET/CT images. Methods: In this study, the standard 18F-fluorodeoxyglucose positron emission tomography/ computed tomography (18 F-FDG PET/CT) images of 21 patients with pulmonary inflammatory pseudotumor (PIPT) and 21 patients with peripheral lung cancer were retrospectively collected. The dataset was used to extract CT-radiomics features from regions of interest (ROI), The intra-class correlation coefficient (ICC) was used to screen the robust feature from all the radiomic features. Using, then, statistical methods to screen CT-radiomics features, which could distinguish peripheral lung cancer and PIPT. And the ability of radiomics features distinguished peripheral lung cancer and PIPT was estimated by receiver operating characteristic (ROC) curve and compared by the Delong test. Results: A total of 435 radiomics features were extracted, of which 361 features showed relatively good repeatability (ICC ≥ 0.6). 20 features showed the ability to distinguish peripheral lung cancer from PIPT. these features were seen in 14 of 330 Gray-Level Co-occurrence Matrix features, 1 of 49 Intensity Histogram features, 5 of 18 Shape features. The area under the curves (AUC) of these features were 0.731 ± 0.075, 0.717, 0.748 ± 0.038, respectively. The P values of statistical differences among ROC were 0.0499 (F9, F20), 0.0472 (F10, F11) and 0.0145 (F11, Mean4). The discrimination ability of forming new features (Parent Features) after averaging the features extracted at different angles and distances was moderate compared to the previous features (Child features). Conclusion: Radiomics features extracted from non-contrast CT based on PET/CT images can help distinguish peripheral lung cancer and PIPT.

Real‐time, high signal intensity, and prolonged detection is challenging because of the rarity of fluorophores with both high photostability and luminescence efficiency. In this work, new donor–acceptor (D–A) molecules for overcoming these limitations are reported. A hybridized local and an intramolecular charge‐transfer excited state is demonstrated to afford high photoluminescence efficiency of these D–A molecules in solution (≈100%). The twisted molecular structure and bulky alkyl chains effectively suppress π–π and dipole–dipole interactions, enabling high luminescence efficiency of 1 and 2 in the solid state (≈94% and 100%). Furthermore, two D–A aggregates exhibit high photostability as evidenced by 4% and 8% of the fluorescence decreasing after 6 h of continuous irradiation in air, which is in sharp contrast to ≈95% of fluorescence decreasing in a reference compound. Importantly, with these molecules, ultrasensitive detection of sulfur mustard (SM) with a record limit of 10 ppb and selective detection of SM in complex matrices are achieved.