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BACKGROUND: Current research on the differentiation of mesenchymal stem cells into endothelial cells mainly focuses on the induction of cytokines or co-culture of two types of cells. Research has been not yet reported on heat shock-treated endothelial cells inducing the differentiation of mesenchymal stem cells into endothelial cells. OBJECTIVE: To investigate the ability of heat shock-treated endothelial cells to induce bone marrow mesenchymal stem cells to differentiate into vascular endothelial cells, and to explore the angiogenic capacity of induced bone marrow mesenchymal stem cells. METHODS: Human bone marrow mesenchymal stem cells were co-cultured with heat shock-treated human umbilical vein endothelial cells in a non-contact manner. The expression of CD31, CD144, VEGFR2 and vWF in the bone marrow mesenchymal stem cells was detected by flow cytometry at 14 days after co-culture. The immunofluorescence of the cells was further verified. In vivo angiogenesis test was detected using hematoxylin-eosin staining in nude mice undergoing subcutaneous transplantation of induced and non-induced bone marrow mesenchymal stem cells. Matrigel angiogenesis test was applied to observe the angiogenic ability of induced and non-induced bone marrow mesenchymal stem cells. RESULTS AND CONCLUSION: After coculture, bone marrow mesenchymal stem cells had paving-stone like structure. Flow cytometry and cellular immunofluorescence results showed an increase in the expression of VEGFR2, vWF, CD31 and CD144 after co-culture. The hematoxylin-eosin staining of the graft showed that the induced bone marrow mesenchymal stem cells arranged in a regular manner and had an angiogenic tendency. The Matrigel angiogenesis test showed that the angiogenic ability of bone marrow mesenchymal stem cells was increased after induction compared with the control group. These findings indicate that co-culture with heat shock-treated human umbilical vein endothelial cells can promote the differentiation of mesenchymal stem cells into endothelial cells, and the specific phenotype of endothelial cells is obviously transformed, which has a certain tendency of angiogenesis. [ABSTRACT FROM AUTHOR]

BACKGROUND Ionic liquids ( ILs) are considered to be one of the future solutions to CO2 emission control because of their high CO2 solubility. Infiltrating ionic liquids into porous materials to prepare a supported ionic liquid membrane ( SILM), could increase the absorption efficiency. RESULTS Four SILMs were prepared from imidazolium-based ILs and PVDF microporous membranes. The CO2 absorption capacities of the SILMs were in the range of 0.88-3.64 mol mol−1, which were much higher than the solubility in ILs. After 20 min desorption at 60 °C or 0.08 MPa negative pressure, desorption rate reached 90%. And under the combined condition of 60 °C and 0.08 MPa, the desorption period was shortened and full desorption was obtained. The renewed SILMs maintained excellent CO2 absorption performance during several absorption-desorption cycles. A new peak at 1274-1284 cm−1 on the surface enhanced Raman scattering ( SERS) spectra indicated the absorbed CO2, and some shifts of typical ILs vibration bands showed some probable structures related to CO2 absorption. CONCLUSION SILMs improved the mass transfer process and resulted in excellent CO2 absorption capacity. SILMs performed well in multiple absorption-desorption cycles, and showed great potential for industrial application. SERS is a feasible method for the characterization of SILMs. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: The coagulation behavior, residual aluminum ratio of three PAC coagulants as well as content and proportion of different residual Al speciation during the treatment of a specific surface water were investigated in this paper. Experimental results suggested that surface adsorption and entrapment effect worked effectively in turbidity removal regarding this specific water. PAC20 was appropriate to remove hydrophilic natural organic matter (NOM), while PAC15 and PAC23 were appropriate to remove hydrophobic fraction NOM. PAC, especially PAC20, could reduce the content of total dissolved Al and dissolved monomeric Al with comparatively higher toxicity. PAC20 showed lower concentration for every residual Al species. The majority of total residual Al existed in the form of unsoluble particulate Al (about 62–93% for PAC15, 65–92% for PAC20 and 54–78% for PAC23). Among total dissolved Al in the effluent treated with PAC15 and PAC23, dissolved organically-bound Al was almost the major speciation (about 40–92% for PAC15 and 37–86% for PAC23). There existed no dissolved organically-bound monomeric Al in purified water treated with three PAC samples. Residual Al ratio of PAC varied in the following order: PAC15 >PAC23 >PAC20. Besides, Al speciation in coagulants likely remained in treated water at lower dosage. [Copyright &y& Elsevier]

Abstract: Coagulation performance, mechanism of poly-aluminum-silicate-chloride (PASiC) and residual Al speciation in the effluent with respect to a specific surface water treatment in China were comprehensively investigated in this study. The impact of OH−/Al3+ and Si/Al molar ratios on the coagulation performance, mechanism and residual Al speciation of PASiC in surface water treatment was discussed as a function of coagulant dosage. It was intended to provide an insight into the relationship between coagulation performance and residual Al. Experimental results revealed that when OH−/Al3+ molar ratio=2.00 and Si/Al molar ratio=0.0500 in PASiC coagulant, PASiC exhibited beneficial coagulation property and relatively lower content of residual Al. Surface bridging and entrapment was more effective compared with charge neutralization during the specific surface water treatment. The majority of residual Al in the effluent existed in the form of insoluble suspended or particulate Al. Dissolved organically bound Al was almost the major speciation in dissolved Al and dissolved inorganically bound monomeric Al was the only component in dissolved monomeric Al. Al in PASiC remained abundant at lower dosages and residual Al concentration could be effectively reduced at the dosages of 12.0–15.0mg/L as Al. [Copyright &y& Elsevier]

Charging capacitive deionization (CDI) at constant voltage (CV) produces an effluent stream in which ion concentrations vary with time. Compared to CV, charging CDI at constant current (CC) has several advantages, particularly a stable and adjustable effluent ion concentration. In this work, the feasibility of removing fluoride from brackish groundwaters by single-pass constant-current (SPCC) CDI in both zero-volt and reverse-current desorption modes was investigated and a model developed to describe the selective electrosorption of fluoride and chloride. It was found that chloride is preferentially removed from the bulk solution during charging. Both experimental and theoretical results are presented showing effects of operating parameters, including adsorption/desorption current, pump flow rate and fluoride/chloride feed concentrations, on the effluent fluoride concentration, average fluoride adsorption rate and water recovery. Effects of design parameters are also discussed using the validated model. Finally, we describe a possible CDI assembly in which, under appropriate conditions, fluoride water quality targets can be met. The model developed here adequately describes the experimental results obtained and shows how change in the selected system design and operating conditions may impact treated water quality.