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Residual antibiotic tetracycline (TC) that is hard to degrade and active has adversely affected public health and ecosystems. Therefore, developing straightforward, rapid, and sensitive probes for TC detection is highly desirable. Herein, we present a facile yet versatile strategy to design and fabricate luminescence turn-on TC sensors by applying the concept of indicator displacement to metal–organic frameworks (MOFs). It is illustrated by an elaborated dual-emitting nanoporous europium–MOF (Eu–MOF) constructed by Eu3+ cations and 2-aminoterephthalic acid (BDC-NH2), in which the former serves as receptors and the latter acts as luminescent indicators. The indicator displacement is based on the competitive interactions within Eu–MOF, which is confirmed by high-resolution mass spectrometry, photoluminescence, and UV–vis spectroscopy. Once Eu–MOF contacts TC, the competitive coordination effect induces the release of BDC-NH2 molecules and the accompanying turn-on blue emission, whereas the red emission of Eu3+ barely changes, thereby resulting in a remarkable ratiometric luminescence response and luminescence color switching from red to blue that is readily observed by the naked eye. The sensitive and quantitative determination of TC is accomplished through multiple readouts involving ratiometric emission intensity and emission color, exhibiting detection limits of 0.08 and 0.95 μM, respectively. Notably, the visual detection of TC is achieved using a smartphone color-scanning app. Considering the excellent tunability in the composition and structure of MOFs and their compatibility with various host–guest interactions applicable to indicator displacement assays, this study helps to create a universal avenue for leveraging MOFs in constructing luminescence turn-on sensors. [ABSTRACT FROM AUTHOR]

Hollow discontinuous Ge/GeO2 nanotubes are successfully prepared after the facile oxidization process in air, which are derived from the C/Ge core–shell nanofibers. Electrospinning and chemical vapor deposition techniques are used to fabricate the carbon nanofiber templates and the Ge shell electrode, respectively. Compared with the C/Ge nanocomposites, the Ge/GeO2 nanotube anode demonstrates improved electrochemical performance due to the enlarged surface area and enough space, which can effectively retard the Ge electrode large volume change during repeated cycling. Full‐battery Ge/GeO2||LiCoO2 is also configured and displays good Li‐ion storage ability. [ABSTRACT FROM AUTHOR]

Aqueous ZIBs are one of the most promising next-generation rechargeable batteries because of the high capacity, high hydrogen evolution overpotential, and chemically stable reversible plating/stripping of the zinc electrode in the mild aqueous electrolyte. However, there are limited cathode materials that can store Zn 2+ reversibly with superior cycling and rate capability. Herein, hierarchically porous nanorods composed of twinborn α-(Mn 2 O 3 -MnO 2 ) heterostructures are proposed as a robust cathode for Zn storage. Thanks to the hierarchically porous nanorod morphology and the abundant interface of the heterostructures involving a built-in electric field, the as-obtained twinborn α-(Mn 2 O 3 -MnO 2 ) electrode delivers a high capacity of 170 mA h g -1 for 2000 cycles at 500 mA g -1 and shows an excellent rate capability of up to 1.5 A g -1 with a capacity of 124 mA h g -1 . The inspiring results achieved exhibit the enormous potential of the high-performance heterostructure cathode for fast and stable ZIBs.

Objective: To investigate the expression of CD22 and its downstream signal molecule spleen tyrosine kinase (SYK) and their phosphorylation of B lymphocytes in patients with immune related pancytopenia(IRP), and to explore the role of CD22 in pathogenesis of IRP., Methods: The expression of CD22, SYK and their phosphorylation, along with the expression of IgG and IgM, which obtained from B lymphocytes in peripheral blood of 46 patients with IRP(22 new diagnosed and 24 remitted patients returned to normal after treatment), 22 healthy controls and 12 chronic lymphocytic leukemia(CLL) patients from February to December 2014 were analyzed by flow cytometry. And the mRNA expression of CD22 in peripheral blood mononuclear cell was determined by real-time quantitative PCR., Results: The ratios of CD22+ cells and phosphorylated CD22(pCD22)+ cells of B lymphocytes in new diagnosed group (60. 03% ± 20. 94% 71. 32% ± 11. 16%) were significantly higher than those in remission group (46. 92% ± 20. 04%, 55. 82% ± 14. 42%), normal control group (46. 86% ± 17. 78%, 53. 28% ± 14. 76%) and CLL group (39. 74% ± 18. 96%, 59. 07% ± 17.09%) (all P <0.05). The ratios of phosphorylated SYK( pSYK) + cells in the four groups had the same trend (all P <0. 05). The ratio of pCD22+ cells/pSYK+ cells in new diagnosed group was significantly lower than that in normal control group and CLL group (27. 39 (5. 06 - 102. 70) vs 55. 95 (15. 25 - 298. 53), 56. 92(5. 60 - 228. 96), both P <0. 05), and pCD22+ cells positively correlated to pSYK+ cells ( r = 0. 341, P < 0. 05). The expression of IgG in new diagnosed group and remission group was significantly higher than that in normal control group, and the expression of IgM in new diagnosed group was significantly higher than that in normal control group and CLL group (all P <0. 05). The expression levels of CD22 mRNA in new diagnosed group was significantly higher than that in remission group, normal control group and CLL group (all P <0. 05)., Conclusions: The BCR signal pathway of B lymphocyte in IRP patients is enhanced, and the quantity and function of CD22 are increased, while which are still insufficient to inhibit B cell proliferation, and these may have some relationships with the pathogenesis of IRP. [Key words] Pancytopenia; Antigens, CD22; Immune related pancytopenia; Spleen tyrosine kinase; Phosphorylation