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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]

Enhancing the treatment efficiency of livestock wastewater by effluent recirculation is investigated in a pilot-scale vertical-flow constructed wetland. The wetland system is composed of downflow and upflow stages, on which narrow-leaf Phragmites communis and common reed Phragmites typhia are planted, respectively; each stage has a dimension of 4 m² (2 m x 2 m). Wastewater from the facultative pond is fed into the system intermittently at a flow rate of 0.4 m³/d. Recirculation rates of 0, 25%, 50%, 100% and 150% are adopted to evaluate the effect of the recirculation rate on pollutants removal. This shows that with effluent recirculation the average removal efficiencies of NH4-N, BOD5 and SS obviously increase to 61.7%, 81.3%, and 77.1%, respectively, in comparison with the values of 35.6%, 50.2%, and 49.3% without effluent recirculation. But the improvement of TP removal is slight, only from 42.3% to 48.9%. The variations of NH4-N, DO and oxidation-reduction potential (ORP) of inflow and outflow reveal that the adoption of effluent recirculation is beneficial to the formation of oxide environment in wetland. The exponential relationships with excellent correlation coefficients (R² > 0.93) are found between the removal rates of NH4-N and BOD5 and the recirculation rates. With recirculation the pH value of the outflow decreases as the alkalinity is consumed by the gradually enhanced nitrification process. When recirculation rate is kept constant at 100%, the ambient temperature appears to affect NH4-N removal, but does not have significant influence on BOD5 removal. [ABSTRACT FROM AUTHOR]

Livestock wastewater has been a major contributor to Chinese cultural eutrophication of surface waters. Constructed wetlands are under study as a best management practice to treat wastewater from dairy and swine operations, but the removal efficiency of pollutants is relatively low. Enhancing the treatment efficiency of livestock wastewater by effluent recirculation was investigated in a pilot-scale vertical-flow constructed wetland. The wetland system was composed of downflow and upflow stages, on which narrow-leaf Phragmites communis and common reed Phragmites Typhia are planted, respectively; each stage has a dimension of 4 m^2 (2 m × 2 m). Wastewater from facultative pond was fed into the system intermittently at a flow rate of 0.4 m^3/d. Recirculation rates of 0, 25%, 50%, 100% and 150% were adopted to evaluate the effect of the recirculation rate on pollutants removal. It shows that with effluent recirculation the average removal efficiencies of NH_4-N, biological oxygen demand (BOD_5) and suspended solids (SS) obviously increase to 61.7%, 81.3%, and 77.1%, respectively, in comparison with the values of 35.6%, 50.2%, and 49.3% without effluent recirculation. But the improvement of TP removal is slight, only from 42.3% to 48.9%. The variations of NH_4-N, dissolved oxygen (DO) and oxidation-reduction potential (ORP) of inflow and outflow reveal that the adoption of effluent recirculation is beneficial to the formation of oxide environment in wetland. The exponential relationships with excellent correlation coefficients (R^2>0.93) are found between the removal rates of NH_4-N and BOD_5 and the recirculation rates. With recirculation the pH value of the outflow decreases as the alkalinity is consumed by gradually enhanced nitrification process. When recirculation rate is kept constant 100%, the ambient temperature appears to affect NH_4-N removal, but does not have significant influence on BOD_5 removal. [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.

A simplified model of sequential N transformations and sink was applied to investigate the relationship between the nitrogen removal and oxygen demand to verify the validity of full nitrification-denitrification mechanism in a newly-built multi-stages constructed wetlands. Average net rates of N mineralization ranged from 0.01 to 0.28 g x (m2 x d)(-1), nitrification from 0.50 to 1.54 g x (m2 x d)(-1), denitrification from 0.41 to 1.13 g x (m2 x d)(-1)(3.4% approximately 35.4% of measured N removal in different stage) and plant assimilation from 0.07 to 0.26 g x (m2 x d)(-1) in the five tanks. Nitrification and denitrification occurred concurrently with BOD removal, even in the first stage receiving the higher-strength wastewater. Surprisingly, net areal nitrification rates, was correlated with BOD removal rates positively. Nitrification rates were also correlated linearly with average NH4+-N concentrations in the cascade tanks. The nitrogenous oxygen demand (NOD) required to support full nitrification of ammonia and mineralized Org-N in the wetland was in the upper range of that expected to be able to be supplied through surface and plant-mediated oxygen transfer. Some potential alternative nitrogen removal pathways with reduced overall oxygen requirements that have relevance to constructed wetlands were discussed.

Phosphorus fractions could enter water body from surface runoff and leachate due to excessive irrigation of centralized farm wastewater. Organic P is more mobile than inorganic P in the soil profile and represents a significant proportion of P present in leachate from irrigated farm soils. A set of parallel experiments were conducted to compare the characteristics of organic phosphorus in leachate. The experiment was established in a complete randomized block design with nine replicates. The plots received different combinations of P fertilizer and different rates of pig slurry, i. e. 100, 200,300, 400 t x (hm2 x a)(-1), accordingly, the phosphorus was added to the plots was 6.2, 12.4, 19.2, 24.8 kg x (hm2 x a)(-1), respectively. Leachate was collected over a year period and analyzed for different P fractions. Physico-chemical fractionation of P in leachate indicated that the majority of the P loss from the irrigated soil occurred in unreactive particulate (77% - 90%) P forms. 31P nuclear magnetic resonance analysis of eight leachate samples indicated that unreactive P was mainly comprised of monoester and diester forms of organic P. The presence of phosphomonoesterase and phosphodiesterase activity in leachate resulted in hydrolysis of 9% - 29% of total unreactive P (TUP), indicating that some of the monoesters and diesters can be eventually hydrolyzed into inorganic P forms during P transport. To the treatment P45 + F200, enzyme hydrolysis showed that 33% of the TUP was present as labile monoester P (LMP), followed by 17% as inositol hexakisphosphate (IHP) and 9% as diesters (phospholipids and nucleic acids). The results suggest that LMP, IHP and diesters are an important component of organic P leaching from the irrigated soil. The identification of these organic P forms will improve our understanding of the mechanisms responsible for their release from soils, so that specific mitigation strategies can be implemented at the P source.

Objective: To explore a method to treat the mostly-isolated finger with its bilateral arteria injury without microsurgery., Methods: To avoid exacerbating iatrogenically the wound, the methods of therapy mainly included the following procedures: debriding carefully, suturing the cutis and subcutaneous layer to fix internally the fracture without Kirschner wire, and not suturing the broken finger nerve or the broken tendon which had rebound. It was used in the emergency operation. After operation, heat therapy and Anisodamine were used to dilate capillary and micrangium of the unbroken soft tissue of the wounded finger, which was anatomically the only base of blood supply of pars of the wounded finger., Results: In the 34 cases, main blood supply of the wounded finger was restored. The wound healed well in 28 cases. In 6 cases of necrosis in the edge of the wound, the necrosis were excised and the cicatricial healing was achieved. In 31 patients followed up, after the fracture had healed, the nerve and tendon were repaired., Conclusion: The methods above should be available for the mostly-isolated finger, especially in a hospital without microsurgery.

Using semi-leafless pea and common pea, the authors studied tendril character, its inheritance law and how to use it in pea breeding. The results were as follows: Semi-leafless pea had well developed tendrils; They twined with each other and formed an arbor structure. This ideal structure had greatly increased lodging resistance capability,improved canopy's air and light level, and remarkably increased new varieties yield. So, semi-leafless pea was one of the most important materials in lodging resistance breeding. Tendril gene, af, and seed color gene i, in semi-leafless pea was linked on chromosome I, and cross-over value was 5.72%.