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A type of strontium and amorphous calcium phosphate dipped premixed injectable tricalcium silicate-based dental root canal sealer was developed as the following protocols. A powder mixture containing tricalcium silicate, strontium carbonate (6, 8, 10, and 12 wt%), zirconia (20 wt%), calcium chloride (6 wt%), and amorphous calcium phosphate (ACP) (5 wt%) was mixed with liquid polyethylene glycol 400 (PEG 400) at a liquid-to-powder ratio of 0.5 mL/g and mechanically ground using a planetary ball to obtain the premixed injectable calcium silicate-based sealer. The sealer's physicochemical property and cytocompatibility were evaluated in vitro. Quantitative data were expressed as mean ± standard deviation, and Student's t -test or a one-way analysis of variance (ANOVA) test were carried out at significant differences with P < 0.05. All the sealer groups had suitable flowability (21.3–33.3 mm, n = 3), setting time (241.87 ± 32.72–299.00 ± 26.05 min, n = 8) and radiopacity basically according to ISO 6876-2012 standard. The pH value generally stabilized between 10 and 12 (n = 5) when the sealer was immersed into deionized water or phosphate buffered solution. The sealing property of root canal sealer was evaluated by dye penetration, 6% strontium groups had the best root canal sealing property among all the groups (1.21 ± 0.17–5.75 ± 0.97) mm, n = 10, P < 0.05). 6% strontium groups bonded together to the dental root canal wall, penetrated the dentinal tubule to occlude the dentinal tubules, formed calcium–silicate–hydrate (C–S–H) network structure, induced a layer of nano hydroxyapatite crystal grown on its surface in simulated body fluid (SBF), showing good biomineralization activity. It also had osteogenic differentiation activity cultured with rat bone marrow mesenchymal stem cells (n = 5, P < 0.05). This sealer provided a potential new filling material for root canal therapy and has promising application prospects. [ABSTRACT FROM AUTHOR]

[Display omitted] • Graphene quantum dots can inhibit the activity of MMPs that are entrapped within the hybrid layer. • Graphene quantum dots and carbodiimide have synergistic effects in the ability of cross-linking collagen fibrils. • Graphene quantum dots and carbodiimide have synergistic effects in the ability of resisting enzymatic hydrolysis. • Graphene quantum dots with carbodiimide can improve the resin–dentin bond durability. Resin-based dental adhesion is mostly utilized in minimally invasive operative dentistry. However, improving the durability and stability of resin–dentin bond interfaces remain a challenge. Graphene quantum dots (GQDs) reinforced by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) were introduced to modify the resin–dentin bond interfaces, thereby promoting their durability and stability. GQDs, EDC, and EDC+GQDs groups were designed to evaluate the effects of GQDs and EDC on collagenase activity, the interaction of GQDs with collagen, and the resin–dentin interface. First, the effects of GQDs and EDC on collagenase activity was evaluated by Collagenase (EC 3.4.24.3) reacting with its substrate. The interaction of GQDs and EDC with collagen were evaluated by cross-linking degree analysis, sodium dodecyl sulfate–polyacrylamide gel electrophoresis, attenuated total reflection Fourier transform infrared spectroscopy and enzymatic hydrolysis. Second, the acid-etched and rinse adhesive system was used to evaluate the resin–dentin bond on the basis of microtensile bond strength, in situ zymography and fluorescence confocal laser scanning microscopy. GQDs could inhibit collagenase activity. GQDs with the aid of EDC could cross-link collagen via covalent bonds and improve the anti-enzymatic hydrolysis of collagen. In the resin–dentin adhesion model, the μTBS of the EDC+GQDs group was significantly higher than the other control groups after thermocycling. The addition of EDC to GQDs could inhibit matrix metalloproteinase activity and promote the integrity of the bonding interfaces after thermocycling. This study presents a novel strategy to modify the resin–dentin interface and provides a new application for GQDs. This strategy has the potential to improve the durability of resin-based restoration in dentistry. [ABSTRACT FROM AUTHOR]

• Using microbial desulfurization technology to reduce the sulfur content of sulfur-rich ores. • Adding surfactants to improve the bioleaching of sulfide ore. • Simulating the dynamic self-heating process of the ore heap. • Preventing spontaneous combustion of sulfide ore from internal causes. The purpose of this research was threefold: to change the surface tension of an ore-leaching solution through adding surfactants, to improve the bioleaching of sulfide ore, and to strengthen the desulfurization effect of microorganisms on sulfide ore. Taking different types of surfactants in various concentrations as the impact factors, we evaluated their effect on the relationship between the change rate of surface tension, the attenuation coefficient of the surfactants, and the ore surface desulfurization rate. The experimental results indicate that when surfactants of different types and of different concentrations are added to an ore-leaching solution, they can change the solution's surface tension by different degrees and can influence the effects of bacterial desulfurization. The experimental combination with the highest surface desulfurization rate had a dosage of bacterial agent (Thiobacillus acidophilus) of 40 mL, a desulfurization treatment time of 5 days, and a surfactant (Tween80) concentration of 0.1 %-a combination that achieved 31.68 % desulfurization. By this method, we effectively promoted the desulfurization effect of Thiobacillus acidophilus on sulfide ore and ultimately improved the leaching effect. We then used the best surfactant as the leaching aid in subsequent experiments on microbial leaching desulfurization. A three-dimensional reconstruction of the temperature field of an ore heap was conducted by simulating the dynamic self-heating process of the ore heap. The final results showed that the self-heating of the sulfide ore heap that we treated by desulfurizing bacteria was hindered to some extent, and therefore the goal of preventing the spontaneous combustion of sulfide ore was achieved. [ABSTRACT FROM AUTHOR]

Epidemiological studies have shown that fat rich western diet contributes to the high incidence of inflammatory bowel disease (IBD). Moreover, accumulated data indicated that fat dietary factor might promote the change of the composition and metabolism in commensal flora. But, the exact mechanisms for fatty diet in gut inflammation are not well demonstrated. In this study, we found that high fat diet (HFD) promoted inflammation and exacerbated the disease severity of dextran sulfate sodium (DSS) induced colitis in mice. Compared with low fat diet (LFD)/DSS mice, shorter colon length, more epithelial loss and crypt destruction and more Gr-1 + myeloid inflammatory cells infiltration in colons were observed in HFD/DSS cohorts. Interestingly, such HFD mediated inflammation accompanied with the dys-regulation of hematopoiesis, and more hematopoiesis stem and progenitor cells were detected in colon and spleen. We further analyzed the effects of HFD and DSS treatment on mucosal DC subsets, and found that DSS treatment in LFD mice mainly dramatically increased the percentage of CD11c + CD103 − CD11b + DCs in lamina propria (LP). While, in HFD/DSS mice, HFD pre-treatment not only increased the percentage of CD11c + CD103 − CD11b + DCs, but also decreased CD11c + CD103 + CD11b + in both LP and mesenteric lymph nodes (MLN) in mice with colitis. This disequilibrium of mucosal dendritic cells in HFD/DSS mice may depend on the reduced levels of buytrate and retinoic acid. Thus, this study declared the effects of HFD on gut microenviroment, and further indicated its potential role in the development of DSS induced colitis. [ABSTRACT FROM AUTHOR]

The objective of this study was to improve the efficiency of microbial desulphurization of sulfide ore by pretreatment with ultrasonic and microwave techniques. Different combinations of ultrasound and microwave were used to pretreat the sulfide ore and compare the microbial desulphurization effect of the treated ore and the raw ore. The experimental results show that ultrasonic and microwave can effectively improve the efficiency of bacterial desulphurization, whereas the pretreatment method of ultrasonic followed by microwave has the best enhancement effect on bacterial desulphurization of sulfide ores. The best experimental combination for microbial desulphurization is ultrasonic power of 300 W, ultrasonic action time of 50 mins and microwave power of 500 W, microwave action time of 20 s. In subsequent self-heating simulations of sulfide ore heaps, the optimal ultrasonic and microwave combination was used to pretreat the ores and the two-dimensional temperature field of the heaps was reconstructed. The results further show that the microbial desulphurization efficiency is increased when the sulfide ore is pretreated with ultrasonic followed by microwave. The purpose of inhibiting the self-heating reaction and preventing spontaneous combustion of sulfide ore was achieved. [ABSTRACT FROM AUTHOR]

Rare-earth based AB 5 -type alloys have wide application prospect in many areas such as gaseous hydrogen storage, hydrogen compressing, Ni/MH batteries etc. But opinions on their cycling degradation mechanism remain controversial, hindering them from further improvement. In this study, the hydrogen storage degradation mechanism of LaNi 5- x Al x ( x = 0, 0.25, 0.5) alloy system is studied using EXAFS as one of the main methods, and meanwhile the functioning mechanism of Al is illustrated. It is found that the hydrogen absorption/desorption plateau becomes tilted and the hydrogen storage capacity is decreased with cycling. These degradation phenomena are caused by the crystal damage due to the lattice strains as well as the mis-occupation of metal atoms during hydrogen absorption/desorption. Al with larger atomic radius stabilizes LaNi 5 lattice structure by decreasing the lattice volume expansion rate upon hydrogenation and detaining the atomic migration during cycling, thus significantly improving the alloys' cycling stability from 89.1% (LaNi 5 ) to 98.2% (LaNi 4.5 Al 0.5 ) after 1000 cycles. [ABSTRACT FROM AUTHOR]

In this paper, a type of heterojunction photocatalyst S-Tyr-NDI-Tyr/TiO 2 was prepared by self-assembly of tyrosine-substituted naphthamide (NDA) and bonding with titanium dioxide. The self-assembly process and driving force of monomer M-Tyr-NDI-Tyr were simulated by theoretical calculation. Taking atenolol as the target pollutant, the photocatalytic performance of the heterojunction photocatalyst under visible light was studied, and the degradation products were analyzed by mass spectrometry. The environmental toxicity of photocatalytic process was evaluated by luminescent bacteria. The principle of high photocatalytic activity of S-Tyr-NDI-Tyr/TiO 2 heterojunction photocatalyst was proposed by analyzing the fluorescence spectrum, photocurrent density and resistance, electron paramagnetic resonance spectrum, free radical capture experiment and energy band position of S-Tyr-NDI-Tyr/TiO 2 heterojunction photocatalyst. In addition, the photocatalytic degradation of different pollutants by S-Tyr-NDI-Tyr/TiO 2 heterojunction photocatalyst was also studied. This work will provide a useful example for the further development of new and efficient organic supramolecular/inorganic semiconductor composite photocatalysts. [Display omitted] • Tyrosine substitution and self-assembly to obtain H-type supramolecule S-Tyr-NDI-Tyr. • Constructed a heterojunction S-Tyr-NDI-Tyr/TiO 2 with high photocatalytic activity. • Pollutants such as atenolol are quickly degraded and mineralized by heterojunction. • Analyzed the degradation path of pollutants and environmental toxicity in detail. [ABSTRACT FROM AUTHOR]