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This paper combines traditional ceramics with advanced ceramics, based on the principle of matching the phase separation temperature of the Na2O–B2O3–SiO2 glass system with the crystallization temperature of TiO2, and uses the melting-phase separation method to directly separate the TiO2 photocatalytic material from the porous glass. The catalyst is tightly combined with the SiO2 carrier, and then the β-FeOOH/TiO2/SiO2 composite material is prepared by the hydrothermal method. X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), infrared spectroscopy (FT-IR) and specific surface area (BET) were used to analyze the crystal structure, morphology and phase composition of the compound. Ultraviolet–visible diffuse reflectance spectroscopy (UV–vis DRS) and photoluminescence spectroscopy (PL) are used to characterize the light absorption characteristics of samples. Using tetracycline hydrochloride as a simulated degradation product, the photocatalytic activity of the composite photocatalyst under visible light was studied. The experimental results show that the double-crystal phase glass-ceramics are prepared by the melting phase separation method, the crystal phase is TiO2, and the amorphous phase is SiO2. A heterojunction was successfully constructed between β-FeOOH and TiO2, which effectively improved the migration efficiency of photogenerated carriers and extended the light response range to 640 nm. The photocatalytic efficiency of 0.2β-FeOOH/TiO2/SiO2 composite photocatalyst to tetracycline hydrochloride (TC) is 77 %. After 3 cycles of photocatalytic degradation test, the composite material still maintains good photocatalytic performance, and the crystal structure has not changed. Superoxide free radicals are the main active substance that degrades TC. This provides a reference for the industrial production of glass-phase TiO2-based composite photocatalyst.

We successfully constructed TiO2-pillared multilayer graphene nanocomposites (T-MLGs) via a facile method as follows: dodecanediamine pre-pillaring, ion exchange (Ti4+ pillaring), and interlayer in-situ formation of TiO2 by hydrothermal method. TiO2 nanoparticles were distributed uniformly on the graphene interlayer. The special structure combined the advantages of graphene and TiO2 nanoparticles. As a result, T-MLGs with 64.3wt% TiO2 showed the optimum photodegradation rate and adsorption capabilities toward ciprofloxacin. The photo-degradation rate of T-MLGs with 64.3wt% TiO2 was 78% under light-emitting diode light irradiation for 150 min. Meanwhile, the pseudofirst-order rate constant of T-MLGs with 64.3wt% TiO2 was 3.89 times than that of pristine TiO2. The composites also exhibited high stability and reusability after five consecutive photocatalytic tests. This work provides a facile method to synthesize semiconductor-pillared graphene nanocomposites by replacing TiO2 nanoparticles with other nanoparticles and a feasible means for sustainable utilization of photocatalysts in wastewater control.

BACKGROUND: High intrarenal pelvic pressure (IPP) induces systemic absorption of irrigation fluid containing bacteria or endotoxins, which is associated with postoperative fever (POF) and even urosepsis. The emphasis of this meta-analysis lies in comparison of IPP and POF between mini-tract percutaneous nephrolithotomy (MPCNL) and standard-tract percutaneous nephrolithotomy (SPCNL). METHODS: Eligible randomized controlled trials (RCTs) were identified from electronic databases from inception to November 2019. Studies selection, quality assessment, data extraction and analysis were accomplished by two independent reviewers using Cochrane Collaboration’s tools. RESULTS: Patients in the MPCNL group experienced higher IPP compared to SPCNL group [mean difference (MD): 8.31, 95% confidence interval (CI): 3.67–12.96, P=0.0005] with highly between-study heterogeneity (P=0.001, I(2)=85%). Notably, the IPP was higher in MPCNL group in different stages of the procedure including introduction, fragmentation and end. However, only two trials were available for pooled analysis. Additionally, the risk of POF in MPCNL was 2.43 times higher than that in SPCNL [odds ratio (OR): 2.43, 95% CI: 1.39–4.27, P=0.002] with no significant between-study heterogeneity (P=0.83, I(2)=0%). The two procedures was comparable on stone-free rate (SFR) (OR: 1.06, 95% CI: 0.61–1.86, P=0.83) and operation time (MD: 5.69, 95% CI: −4.54 to 15.91, P=0.28). CONCLUSIONS: Current evidence indicates that MPCNL is an effective alternative to SPCNL with comparable SFR. IPP and POF is significantly higher during MPCNL compared to SPCNL. Intraoperative detection of IPP is of great significance for ensuring safety and reducing postoperative complications, especially for patients with MPCNL and the duration of stone fragmentation. Further large well-designed trials are warranted to confirm our findings.

Novel Ag3PO4@Cu2O core@shell heterojunction photocatalysts were fabricated through liquid phase reduction and chemical deposition method. Flower-like structures Cu2O were loaded on the surface of Ag3PO4 nanorods. The prepared Ag3PO4@Cu2O exhibited highly efficient photocatalytic activity for photodegradation of MB under visible-light irradiation. The possible mechanism for the excellent performance of this structure was also established.

An ideal photocatalyst that can promisingly convert CO2 should have suitable band gap and fully consider the activation of reaction. However, well-designed photocatalytic materials with these aspects are very limited. This study reports a highly efficient CO2 reduction photocatalyst based on ZnS nanocrystals which can be rapidly synthesized at room temperature and operated under solar light irradiation at all-inorganic reaction system. Two functional elements, Cu and Cd, are respectively used as dopant and cocatalyst of ZnS nanocrystal for selective CO2 reduction. Cu+ doping expands the photoabsorption of ZnS into visible light region and the simultaneous Cd2+ surface modification significantly improves the activity of CO2 reduction with 99% formic acid selectivity. A combination of charge density distribution and electronic state studies reveal that the Cd s orbital displays obviously higher density of states near band-edge with a relatively lower lying band center than that of Zn s orbital. This will greatly favor the charge transfer from conduction band of ZnS to the surface state created by Cd2+ for catalyzing CO2 reduction.

Rice grain with excessive cadmium (Cd) is a major source of dietary Cd intake and a serious threat to health for people who consume rice as a staple food. The development of elite rice cultivars with consistently low Cd content is challenging for conventional breeding approaches, and new strategies urgently need to be developed. Here, we report the development of new indica rice lines with low Cd accumulation and no transgenes by knocking out the metal transporter gene OsNramp5 using CRISPR/Cas9 system. Hydroponic culture showed that Cd concentrations in shoots and roots of osnramp5 mutants were dramatically decreased, resulting in rescue of impaired growth in high Cd condition. Cd-contaminated paddy field trials demonstrated that Cd concentration in osnramp5 grains was consistently less than 0.05 mg/kg, in contrast to high Cd concentrations from 0.33 mg/kg to 2.90 mg/kg in grains of Huazhan (the wild-type indica rice). In particular, the plant yield was not significantly affected in osnramp5 mutants. Furthermore, we developed promising hybrid rice lines with extremely low Cd content in grains. Our work supplies a practical approach to developing Cd pollution-safe indica rice cultivars that minimizes Cd contamination risk in grains.

Nano-hydroxyapatite samples with different morphologies were successfully prepared by chemical precipitation method using polyethylene glycol (PEG) as a template. The phase composition, micro-morphology and surface functional groups of the nano-hydroxyapatite samples were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM), respectively. The results reveal that the mirco-morphology of hydroxyapatite can be effectively controlled by adjusting pH values in the preparation. Moreover, the growth mechanism of HAp with different morphologies was also discussed.

The original version of this article unfortunately contained a mistake. In the Abstract section the sentence "Furthermore, the drug release mechanism was investigated by kinetic models and a first-order relationship was concluded, which indicated that the drug release is a simple diffusion process cohydroxyapatite/methotrexate complexntrolled by gradient drug concentration." was wrong. It should read as "Furthermore, the drug release mechanism was investigated by kinetic models and a first-order relationship was concluded, which indicated that the drug release is a simple diffusion process controlled by gradient drug concentration."

Cu2ZnSnS4 (CZTS) thin film photocatalytic water splitting for hydrogen production under visible light irradiation has been reported together with CZTS nanoparticles prepared by ultrasonic spray pyrolysis and hydrothermal method, respectively. CZTS thin film provided higher H2 production rate (68.68 μmol · g−1 · h−1), which was 32 times higher than that of CZTS nanoparticles (2.08 μmol · g−1 · h−1) without loading any noble metals. What’s more, photocatalytic activity of CZTS thin film remained 94% after 48 h which confirmed the good stability and reusability of CZTS thin film. CZTS thin film is a potential and durable candidate for photocatalysis.

In this study, g-C3N4/methotrexate (g-C3N4/MTX) nanohybrids were obtained via a self assembly method. XRD and TEM demonstrated that bulk g-C3N4 had been stripped into thin nanosheets with size range of 150-250 nm. FTIR investigation indicated that the self assembly of the hybrid was attributed to the hydrogen bond between g-C3N4 nanosheets and MTX molecules. It is confirmed by the UV-vis spectra that the hybrids can achieve a sustained drug release within long period for 70 h. Furthermore, the drug release mechanism was investigated by kinetic models and a first-order relationship was concluded, which indicated that the drug release is a simple diffusion process cohydroxyapatite/methotrexate complexntrolled by gradient drug concentration. Cell viability tests confirmed that g-C3N4 presented excellent biocompatibility and g-C3N4/MTX hybrids had obvious suppression efficiency on MG63 cells which showed a positive correlation to the drug concentration and incubation time.

Objectives To investigate the effect of cyclic hydrostatic pressure on the expression of uroplakins and the role of extracellular regulated protein kinases 1/2 (ERK1/2) in the hydrostatic pressure-induced uroplakin expression of human urothelial cells (UCs). Methods Human UCs were seeded into a cell culture flask and subjected to cyclic hydrodynamic pressures for 24 h. Pressure parameters were set as follows: static, 100 cm H2O, 200 cm H2O and 300 cm H2O pressure. Real-time polymerase chain reaction (RT-PCR) and western blot were used to detect the expression of uroplakins. The role of the ERK1/2 was investigated using ERK1/2 inhibitor. Results Compared with the 0 cm H2O control group, 200 cm H2O hydrostatic pressure significantly increased the expression of uroplakins, however, 100 cm and 300 cm pressures could not promote uroplakin expression. Hence, ERK1/2 expression was also detected under 200 cm H2O hydrostatic pressure. Western blot showed that 200 cm H2O pressure promoted the expression of ERK1/2. ERK1/2 inhibitor decreased the pressure-induced ERK1/2 activivation and uroplakin expression. Conclusions Cyclic hydrostatic pressure increases the expression of uroplakins via activating ERK1/2 signaling pathway in human UCs, and 200 cm H2O pressure may be an optimal stress parameter to promote the uroplakin expression.

In this study, for the first time, a laminated hydroxyapatite (HAp)/ methotrexate (MTX) complex was synthesized by in situ method using polyethylene glycol (PEG, MW8000) as template. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and UV–vis spectrophotometer were used to investigate the morphology, interaction and drug release property of synthesized HAp/MTX complex. SEM investigation indicated that laminated HAp/MTX complex with size ranging of 150–200 nm was obtained in the present of PEG molecules. The interaction between COO − of MTX and Ca 2+ of HAp was confirmed by FTIR investigation. In vitro drug release test indicated that the complex exhibits slow drug release ability which attributed to the laminated structure and interaction between MTX and HAp. Furthermore, it is confirmed that the drug release kinetic fitted Rigter-Pappas-order equation best which indicated that the drug release mechanism is a combination of MTX diffusion and HAp/MTX complex dissolution.

In this study, morphology effect of nano-hydroxyapatite as a drug carrier was investigated for the first time. Hydroxyapatite/methotrexate (HAp/MTX) hybrids with different morphologies were successfully prepared in situ using polyethylene glycol (PEG) as a template. SEM, TEM, XRD and FTIR results confirmed that the hybrids of different morphologies (laminated, rod-like and spherical) with similar phase composition and functional groups were obtained by changing the preparation parameters. UV-Vis spectroscopy was used to identify the drug loading capacity and drug release mechanism of the three hybrids with different morphologies. It is concluded that the laminated hybrid exhibits a higher drug loading capacity compared to the other two hybrids, and all the three hybrids showed a sustained slow release which were fitted well by Bhaskar equation. Additionally, the result of in vitro bioassay test confirms that the inhibition efficacy of the three hybrids showed a positive correlation to the drug loading capacity.

In this study, a series of comparative studies for the effect of potassium acetate(KAc) on the physical properties of the Longyan Clay were performed. Microwave was used to promote the intercalating process. The d-spacing increased with the increasing adding amount. As the addition of KAc reached 20wt.%, the d-spacing of illite[002] increased from 9.9505A to 10.1311 A, the kaolinite[001] increased from 7.1439A to 7.2251 A, and a new diffraction peak emerge at the 2θ of 6.181° corresponding to d-spacing of 14.286 A. The consequence of XRD, showed that the crystalline structure of was significantly altered by grinding. Meanwhile, the variations of particle size and surface characteristics were also investigated using SEM analysis.