This study aims to evaluate the effects of mineral types and water on the adhesion properties and debonding behaviours of bitumen-mineral interface systems. A molecular dynamics modelling approach was employed to simulate the interactions between minerals and bitumen with and without the presence of water. Four representative minerals (quartz, calcite, albite and microcline) were selected to build the mineral-bitumen interface systems and the mineralwater-bitumen interface systems in the molecular dynamics models. The adhesion property between minerals and bitumen was quantified by work of adhesion, defined as the energy required to separate a unit area of the bitumen-mineral interface. The debonding behaviour between minerals and bitumen is characterised by work of debonding, defined as the energy required to displace bitumen by water at the mineral-bitumen interface. The simulation results were validated by available experimental results reported in the literature. It was found that the work of adhesion and the work of debonding for the four bitumen-minerals interface systems are ranked microcline > albite > calcite > quartz at both dry and wet conditions. Moisture can reduce the adhesion between minerals and bitumen by 82%, 84%, 18% and 1% for the quartz, calcite, albite and microcline, respectively. The adhesion between minerals and bitumen is attributed to the non-bond interaction energy, in which the major component is van der Waals interaction for neutral minerals (e.g., quartz) and the electrostatic interaction for the alkali minerals (e.g., calcite, albite and microcline). The bitumen-mineral debonding is a thermodynamically favourable process with reduced total potential energy of the system. It is concluded that the bitumen-mineral adhesion and debonding behaviours strongly depends on the chemistry and mineralogical properties of the minerals. This work provides a fundamental understanding of the adhesion and debonding behaviours of the bitumen-mineral interface at the atomistic scale.

Abstract Immune checkpoint blockade treatments bring remarkable clinical benefits to fighting several solid malignancies. However, the efficacy of immune checkpoint blockade in breast cancer remains controversial. Several clinical trials of immune checkpoint blockades focused on the effect of CTLA4 and PD1/PDL1 checkpoint inhibitors on breast cancer. Only a small portion of patients benefited from these therapies. Here we systematically investigated the expression of 50 immune checkpoint genes, including ADORA2A, LAG-3, TIM-3, PD1, PDL1, PDL2, CTLA-4, IDO1, B7-H3, B7-H4, CD244, BTLA, TIGIT, CD80, CD86, VISTA, CD28, ICOS, ICOSLG, HVEM, CD160, LIGHT, CD137, CD137L, OX40, CD70, CD27, CD40, CD40LG, LGALS9, GITRL, CEACAM1, CD47, SIRPA, DNAM1, CD155, 2B4, CD48, TMIGD2, HHLA2, BTN2A1, DC-SIGN, BTN2A2, BTN3A1, BTNL3, BTNL9, CD96, TDO, CD200 and CD200R, in different subtypes of breast cancer and assessed their prognostic value. The results showed that the expression patterns of these 50 immune checkpoint genes were distinct in breast cancer. High expression of B7-H3 mRNA was significantly associated with worse overall survival (OS), especially in patients with luminal A and luminal B breast cancer. The mRNA expression levels of TIM-3, ADORA2A, LAG3, CD86, CD80, PD1 and IDO1 had no relationship with OS in breast cancer. High expression levels of CTLA-4 and TIGIT were correlated with favorable prognosis in breast cancer. Interestingly, we observed that B7-H3 expression was negatively correlated with the efficacy of cyclophosphamide (CTX). In summary, our study suggested that B7-H3 has potential prognostic value in breast cancer and is a promising target for immune therapy.

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This work presents a study on intermediate pyrolysis of the organic fraction of municipal solid waste (OFMSW) and characterisation of organic liquid product (pyrolysis oils) with particular focus on aging and rheological characteristics. The feedstock was a real municipal waste sample received from a local waste treatment plant. Shredded into small particles, it contained a high amount of moisture (51.2%) and ash (17.4%). A pilot-scale intermediate pyrolysis system was used to process the material. The process mass balance showed that the yield pyrolysis oil was 10.6%. GC-MS and FTIR experiments showed that the accelerated aging (80°C for 24h) did not cause an obvious change in the liquid chemical composition, but led to a significant reduction in the solids and moisture contents. The dynamic viscosity tests demonstrated that the intermediate pyrolysis oil derived from OFMSW is a non-Newtonian fluid. The dynamic viscosity of the pyrolysis oil reduced with the increase of temperature or shear rate, which can be modelled by WLF function and the Carreau model, respectively. A shear rate-temperature superposition method was proposed to construct the viscosity master curve at a wide range of shear rate, where WLF function was employed to model the shear rate-temperature shift factor. The accelerated aging caused an obvious reduction in dynamic viscosity, resulting from the decomposition of the semisolid organic agglomerates in the solids content during the aging of the OFMSW intermediate pyrolysis oil. The relatively high viscosity and reduced viscosity after aging of the OFMSW pyrolysis oil has indicated its potential for application as a substitute of the light fraction in the bitumen for road construction.

This study investigated the solidification/stabilization of fly ash containing heavy metals using the Portland cement as a binder. It is found that both the cement/fly ash ratio and curing time have significant effects on the mechanical (i.e., compressive strength) and leaching behaviors of the stabilized fly ash mixtures. When the cement/fly ash ratio increases from 4 : 6 to 8 : 2, the increase of compressive strength ratio raises from 42.24% to 80.36%; meanwhile, the leaching amount of heavy metals decreases by 2.33% to 85.23%. When the curing time increases from 3 days to 56 days, the compressive strength ratio of mixtures raises from 240.00% to 414.29%; meanwhile, the leaching amount of heavy metals decreases by 16.49% to 88.70%. The decrease of compressive strength with the lower cement/fly ash ratios and less curing time can be attributed to the increase of fly ash loading, which hinders the formation of ettringite and destroys the structure of hydration products, thereby resulting in the pozzolanic reaction and fixation of water molecules. Furthermore, the presence of cement causes the decrease of leaching, which results from the formation of ettringite and the restriction of heavy metal ion migration in many forms, such as C-S-H gel and adsorption.

This paper aimed at assessing the structural performance and sustainability of cold recycled asphalt pavements. Four cold recycling technologies were investigated, including the cold centralplant recycling with emulsified and foamed asphalt binders (i.e., CCPR-E and CCPR-F), and the cold in-place recycling with emulsified and foamed asphalt binders (i.e., CIR-E and CIR-F). Firstly, the laboratory tests were conducted to comprehensively evaluate the dynamic modulus, rutting, and cracking performance of cold recycled asphalt mixtures. Subsequently, these laboratory results were used to determine the inputs of cold recycled asphalt mixtures for the Pavement ME Design program, which was employed to predict the pavement performance. Meanwhile, the National Center for Asphalt Technology also constructed four cold recycled pavement sections in the field. The monitored and predicted pavement performance showed similar trends in the first two years, but the Pavement ME Design program over predicted the rut depth of these sections. The pavement performance results confirmed that the bottom-up fatigue cracking was a negligible distress mode for cold recycled asphalt pavements. In the following, the life cycle cost analysis and life cycle assessment were conducted to evaluate the four different cold recycling projects. The life cycle cost analysis results demonstrated that all of the four cold recycling projects yielded less net present values than the HMA project. The life cycle assessment data indicated that the cold recycling technologies reduced the energy consumption by 56-64%, and decreased the greenhouse gas emissions by 39-46%. Finally, this study found that the overlay and asphalt treated base thicknesses and climatic conditions had significant impact on the performance of cold recycled asphalt pavements.

As a by-product from the incineration of municipal solid waste (MSW), fly ash usually contains mobile heavy metals that may engender severe pollution when reused. In this study, fly ash was solidified with cement and a chelating agent to immobilize these polluting elements. The possibility of using the solidified fly ash for pavement materials was also assessed through mechanical and environmental perspectives. According to the results, the strength of solidified fly ash was found proportional to both the cement/fly ash ratio and curing time. This indicated that the increase of fly ash loading reduced the concentration of products from cement hydration, and thus destroyed the structure of the products of hydration. With the increase of freeze–thaw cycles, the compressive strength of cement-stabilized fly ash decreased between days 7 and 14, and then increased between days 14 and 28. Subsequently, the finite element analysis showed that placing the solidified fly ash layer as a pavement material between an unbound base course and subgrade was beneficial to prolong fatigue life and reduce rutting distress of asphalt pavements. Finally, leachability of metals from the mixtures was tested, which showed that leaching concentration decreased as the cement/ash ratio, curing time, and chelating agent content increased.

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