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Inspired by the working principle of natural spiderweb and long-persistence phosphors, we have synthesized a spiderweb-like nanocomposite in which CoS quantum dots are confined in N-doped carbon frameworks/carbon nanotubes (CNTs). The intimate combination of three-dimensional conductive networks of CoS/CNTs with abundant active sites allows effective capture of sulfate radicals via both physical confinement and chemical bonding and accelerates the redox kinetics significantly. Furthermore, in virtue of the light storing and luminescence behaviors of long-persistence phosphors, the all-weather CoS/CNTs produced can realize an optimum degradation efficiency of 64% under dark conditions. Overall, this work reveals a significant step forward for building a desirable all-weather catalyst with abundant active sites for potential use in degradation under dark conditions. [ABSTRACT FROM AUTHOR]

A great challenge for the application of metal–organic frameworks (MOFs) as peroxymonosulfate (PMS) activators for environmental applications in pollutant removal is their stability and activity. Pyrolysis of the MOF organic linkers under an inert gas atmosphere can maintain or improve the coordinatively unsaturated metal site (CUMS) activation ability of the MOFs and at the same time solve the problem of the collapsible and unstable MOF structure. Herein, we report a series of novel coordinatively unsaturated cerium-doped MIL-101(Fe(III)) compounds (denoted as Ce-MIL-101) with different shapes, containing mixed-valence Fe(II)/Fe(III) and Ce(III)/Ce(IV) sites, as new PMS activators, through the total release of solvent molecules under a controlled thermolysis reduction process at 500 °C under N2 to increase the number of CUMSs. The resulting rod-like cerium-doped Fe3O4 materials exhibited superior stability and a higher number of active sites compared to octahedral cerium-doped Fe3O4. The XPS results reveal a growth of the oxygen vacancies (77.8%) and a large number of electron-deficient metal sites. Following the great improvement of the number of CUMSs, the performance (apparent rate constant) of CUMSs/MIL-101(Fe,Ce) in the activation of PMS for the degradation of bisphenol A (BPA) increased by a factor of up to 2.5 relative to that of pristine MIL-101(Fe). Density functional theory (DFT) calculations further clarified the nature of the PMS active sites at the atomic level. These new insights confirm a novel strategy for the synthesis of a highly active catalyst with different shapes for environmental remediation by controlling the CUMSs. [ABSTRACT FROM AUTHOR]

Objective: To investigate the morphological, histological and ultrastructural changes of acute closed rupture of Achilles tendon, in order to clarify the pathological basis of the injury and to explore the significance., Methods: From January 2015 to January 2019, 35 patients with acute Achilles tendon rupture who underwent the minimally invasive Achilles tendon suture technique were retrospectively analyzed. Among these patients, 12 cases in acute open Achilles tendon rupture group included 10 males and 2 females, with an average age of (35.1±9.7) years old ranging from 19 to 50, and the time from injury to operation was 2 to 8 hours with an average of(5.6±1.8);23 cases in acute closed Achilles tendon rupture group included 21 males and 2 females, with an average age of (35.5±6.6) years old ranging from 18 to 50, and the time from injury to operation was 3 to 15 hours with an average of (7.5±3.1). The gross appearance and imaging findings of the broken end of Achilles tendon tissue in the two groups were compared by naked eye observation and foot and ankle MRI at 4 to 6 hours before operation. HE staining, scanning and fluoroscopic electron microscopy, immunohistochemistry(Sirius red staining) were performed on the intraoperative Achilles tendon tissue specimens at 1 to 2 days after operation, the collagen fiber degeneration and local fat infiltration, collagen fiber shape, cell morphology and function, and the distribution of typeⅠand type Ⅲ collagen fibers in Achilles tendon were compared between the two groups., Results: Compared with the acute open Achilles tendon rupture group, the acute closed Achilles tendon rupture group had poor elasticity, hard texture, moderate edema, irregular shape of Achilles tendon broken end, horsetail shape, and more calcification around the broken end. HE staining results:the collagen fibers in the Achilles tendon of the acute open Achilles tendon rupture group were arranged irregularly, with hyaline degeneration and fat infiltration;The results of electron microscopy showed that collagen arranged disorderly and fibroblasts atrophied in the acute closed Achilles tendon rupture group. Immunohistochemical(Sirius staining) results:the proportion of collagenⅠin the acute open Achilles tendon rupture group and the acute closed Achilles tendon rupture group was(91.12±4.34)% and(54.71±17.78)% respectively, and the proportion of collagen Ⅲ was (8.88±4.34)% and (45.29±17.78)% respectively. The content of collagenⅠin the acute closed Achilles tendon rupture group was lower than that in the acute open Achilles tendon rupture group, and the content of collagen Ⅲ in the acute closed Achilles tendon rupture group was higher than that in the acute open Achilles tendon rupture group( P <0.05)., Conclusion: The morphology, histology and ultrastructure of the acute closed ruptured Achilles tendon are significantly altered compared with the normal Achilles tendon. The original fine and orderly spatial structure cannot be maintained, part of collagen Ⅰ is replaced by collagen Ⅲ, and the toughness and strength of the tendon tissue decreased, which may be the feature of degeneration of the Achilles tendon and an important pathological basis for closed Achilles tendon rupture.