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To decrease the usage of petroleum asphalt and improve waste recovery, two different groups of recycled oils were selected to improve the low-temperature performance of asphalt binders in cold region. The multiple stress creeps recovery (MSCR) test, linear amplitude sweep (LAS) test and bending beam rheometer (BBR) test were performed to evaluate the rheological properties of recycled oil modified asphalt (ROMA). The thermal stress and double edge notched tension (DENT) tests were employed to characterise the low-temperature cracking resistance and ductile resistance of the ROMA, respectively. The results of this study showed that recycled oils significantly improved the low-temperature and fatigue performance of asphalt, which is manifested in a drop in the low-temperature critical cracking temperature of asphalt by 3°C, increase in crack tip opening displacement (CTOD) by 72.8%, and extension of fatigue life by 178.9%. The addition of recycled oils reduced the percentage of large molecule size (LMS) while increasing the percentage of medium molecule size (MMS) of the asphalt, which contributes to the better low-temperature performance of the ROMA. The results from this study provide insights into the reclamation of waste oils and developing the low-temperature modifier of asphalt pavements in cold region. [ABSTRACT FROM AUTHOR]

As a solid waste, graphite tailings (GTs) have caused serious harm to the environment and nearby residents, and using GTs as pavement materials can not only solve the environmental problems but also promote sustainable pavements. To this end, this study experimentally explored the feasibility of using three kinds of GTs (named GT-A, GT-H, and GT-W) as fillers to prepare asphalt mastics and analysed their micro properties, mechanical properties, asphalt-filler interaction, and dielectric properties. The results show that graphite tailings asphalt mastics (GTAMs) have less bee-like structures, which causes greater average adhesion compared with limestone asphalt mastic (LAM). Besides, because GTs have a rougher micromorphology, a larger particle size, a greater density, a higher specific surface area, and a stronger interaction with asphalt than those of limestone, they exhibit better mechanical properties than LAM. Further, GTAMs possess superior dielectric properties than LAM due to the chemical composition of GTs, which contains more polar components than limestone. Among the three GTAMs, GTAM-A has the best overall performance, followed by GTAM-H, and then GTAM-W. This study proposes a feasible solution for the comprehensive recycling and reuse of GTs as raw materials for sustainable asphalt pavements while lowering economic and environmental costs. [ABSTRACT FROM AUTHOR]

A simple LC-MS/MS method facilitated by salting-out assisted liquid-liquid extraction (SALLE) was applied to simultaneously investigate the pharmacokinetics of trans-resveratrol (Res) and its major glucuronide and sulfate conjugates in rat plasma. Acetonitrile-methanol (80:20, v/v) and ammonium acetate (10 mol L−1) were used as extractant and salting-out reagent to locate the target analytes in the supernatant after the aqueous and organic phase stratification, then the analytes were determined via gradient elution by LC-MS/MS in negative mode in a single run. The analytical method was validated with good selectivity, acceptable accuracy (>85%) and low variation of precision (<15%). SALLE showed better extraction efficiency of target glucuronide and sulfate conjugates (>80%). The method was successfully applied to determine Res and its four conjugated metabolites in rat after Res administration (intragastric, 50 mg kg−1; intravenous, 10 mg kg−1). The systemic exposures to Res conjugates were much higher than those to Res (AUC0- t, i.v., 7.43 μ m h; p.o., 8.31 μ m h); Res-3- O-β- d-glucuronide was the major metabolite (AUC0- t, i.v., 66.1 μ m h; p.o., 333.4 μ m h). The bioavailability of Res was estimated to be ~22.4%. The reproducible SALLE method simplified the sample preparation, drastically improved the accuracy of the concomitant assay and gave full consideration of extraction recovery to each target analyte in bio-samples. [ABSTRACT FROM AUTHOR]

1. This study aimed to investigate the potential impact of epigallocatechin-3-gallate (EGCG) on the pharmacokinetic behaviors of simvastatin and its metabolite simvastatin acid and explored the possible role of metabolizing enzymes and transporters of this food–drug interaction. 2. Female SD rats were intravenously administered with EGCG (5 mg/kg), ketoconazole (10 mg/kg) and rifampin (10 mg/kg), followed by intravenous administration of 2 mg/kg simvastatin.In vitro, the effects of EGCG on Cytochrome P450 enzymes (CYP450) and organic anion transporting polypeptides (OATPs) were studied using human hepatic microsomes and human embryonic kidney 293 (HEK293) cells overexpressing OATP1B1 or OATP1B3. The results showed that areas under concentration–time (AUC) curves of simvastatin and simvastatin acid increased by 2.21- and 1.4-fold while the clearance was reduced by 2.29- and 1.4-fold, respectively, when co-administered with EGCG.In vitroexperiments suggested the inhibitory effect of EGCG on CYP enzymes (IC50: 18.37 ± 1.36 μM, 26.08 ± 1.51 μM for simvastatin and simvastatin acid, respectively). Simvastatin transport by OATP1B1 and OATP1B3 was also inhibited by EGCG (IC50: 8.68 ± 1.27 μM and 22.67 ± 1.42 μM, respectively). 3. The presently reported novel food–drug interaction between EGCG and simvastatin involves the inhibition of not only CYP450 enzymes but also OATPs by EGCG. [ABSTRACT FROM AUTHOR]