Converting coastal silt into subgrade soil with biochar as reinforcing agent, CO2 adsorbent, and carbon sequestrating material.

Large amounts of coastal silt produced annually is urgent to be treated with a feasible strategy. This study converted it into subgrade soil by cement solidification for resource utilization. Biochar was used as exogenous additive for enhancing compressive strength of the product, simultaneously achieving carbon sequestration. Three biochars derived from peanut shells (PSBC), cow dung (CDBC) and sewage sludge (SSBC) at 300 °C, 500 °C and 700 °C pyrolysis, were added into raw materials with 1%, 2% and 5%, respectively. All biochars significantly improved the compressive strength of the subgrade soil by 20-110%. Biochar catalyzed cement hydration reactions to produce more Ca(OH)2, CaCO3 and calcium silicate hydrates (C-S-H gel). The catalytic capacity of different biochars followed the order of SSBC > PSBC > CDBC. Addition of 2% SSBC500 induced the greatest increase in 28 d-strength from only 1.0 MPa-2.1 MPa, which was due to that 500 °C biochar had a suitable specific surface area and porosity. Biochar facilitated CO2 capture (absorption) during the hydration reactions at the initial 48 h with 55-70 mg g-1. The high alkalinity and water holding capacity of biochar contributed to the absorption of CO2; the high content of minerals in SSBC compared to CDBC and PSBC promoted chemical conversion of CO2 to carbonate. Besides, the biochar itself as carbon rich material was encapsulated in the subgrade soil, which can be regarded as a long-term carbon sequestration strategy. Carbon budget analysis demonstrated that converting one ton dry silt into subgrade soil with addition of 2% biochar could increase CO2 sequestration from 11 kg to 36-94 kg. This study proposes a novel strategy of using biochar to strengthen the subgrade soil simultaneously achieve long-term carbon sequestration.

miR-150-504-519d inhibits the growth of human colorectal cancer cell line SW48 and downregulates c-FLIP receptor.

microRNAs (miRNAs) are noncoding RNAs that regulates the expression of target messenger RNAs (mRNAs). c-FLIP is an inhibitor of cell apoptosis through inhibition of caspase 8. miR-150, miR-504, and miR-519d were related to cancer cell proliferation, invasion, and migration in colorectal cancer (CRC). However, the role of miR-150-504-519d in CRC has not been studied and the relationship between miR-150-504-519d and c-FLIP remains unclear. In this study, we found that c-FLIP was upregulated in CRC tissues, without detectable expression in normal CRC tissues. Using SW48 cell line, we further showed that miR-150-504-519d inhibited migration, invasion, and promoted apoptosis of SW48 cells. Moreover, in SW48 cell line transfected with miR-150-504-519d, the protein expression of c-FLIP was significantly lower compared with cells transfected with scramble. Our results demonstrated upregulation of c-FLIP in CRC, which was downregulated in SW48 cells after the transfection of miR-150-504-519d, suggesting that manipulation of miR-150-504-519d expression might be a novel approach for the treatment of colorectal cancer.

Polyphenol-Based Paclitaxel Prodrug Self-Assembled Nanoplatform for Tumor Synergistic Therapy.

With the development of nanomedicine, studies focus on self-assembled nanoplatforms to reduce the toxicity of paclitaxel (PTX), promote the immune function at low-toxicity PTX, and achieve tumor synergistic therapy. Herein, a new nanoplatform was prepared with self-assembled 5-hydroxydopamine (DA)-PTX@tannic acid (TA)-Fe3+ nanoparticles (TDPP NPs) by consolidation of targeted DA-PTX and TA with the assistance of coordination between polyphenols and Fe3+. The polyphenol-based TDPP NPs can reduce the toxicity of PTX and thereby realize the in vitro and in vivo synergistic effect against tumors. The low-toxicity TDPP NPs can enhance the expression of CD40 immune protein. Moreover, the TDPP NPs possessed a small size (52.2±4 nm), high drug loading efficiency (95%), and stable pharmacokinetics, ensuring high tumor accumulation of TDPP NPs by enhanced permeability and retention effect. Our work sheds new light on the nanoformulation of PTX with low toxicity and synergistic therapy effect, which may find clinical applications in the future.

Enhancement of floatability of low-rank coal using oxidized paraffin soap.

The processing of low-rank coal is becoming more urgent with depletion of high-rank coal and severe environmental pollution in China. The flotation of low-rank coal suffers poor efficiency with hydrocarbon oils unless it is at a high dose. A representative non-polar oil, diesel oil (DO), was used as a collector to float a long-frame coal. The feasibility of oxidized paraffin soap (OPS) was explored to improve flotation performance. Experimental measurements (polarized optical microscopy, zeta potential, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, contact-angle analysis) were used to explore the influence of OPS in low-rank-coal flotation. Poor flotation performances of coal samples were received using OPS or DO as collectors at an economical dose. The flotation efficiency of coal samples was improved considerably upon addition of OPS plus DO. OPS reduced the surface tension of aqueous solutions and promoted dispersion of DO in suspensions. Addition of OPS plus DO reduced the absolute value of the zeta potential on coal particles. Moreover, OPS improved DO adsorption on low-rank coal particles, and the hydrophobicity of low-rank coal was improved visibly. OPS reduced the contact angles of coal-bubble and coal-DO in aqueous solution, which enhanced the adhesion probability of particles to bubbles. This study suggests that OPS is an effective surfactant for improving the floatability of low-rank coal.

Synergistic adsorption of polar and nonpolar reagents on oxygen-containing graphite surfaces: Implications for low-rank coal flotation.

Conventional oily collectors cannot improve the floatability of low-rank coal because of the presence of containing-oxygen groups on the mineral surface, and the effect of the application of a single polar reagent is also limited. In this study, an innovative approach using molecular dynamics simulations to study the adsorption of mixed collectors on an oxygen-containing graphite surface was carried out. The adsorption structures of the collectors were clearly revealed, which has important implications for flotation recovery. In the simulations, when a nonpolar collector, dodecane, was used alone, it was only adsorbed on the carbon atom sites, and the hydrophilic oxygen-containing groups were not covered and remained exposed. In contrast, when a polar collector, dodecanoic acid, was used alone, the molecules self-aggregated, which reduced the surface coverage and increased the collector consumption. However, the use of a mixture of nonpolar and polar molecules resulted in a good dispersion over the mineral surface and significantly improved the coverage of oxygen-containing groups. The nonpolar molecules could be adsorbed on the oxygen-containing sites, being directed by the polar molecules, resulting in a synergistic effect. In addition, water contact angle tests show that the mixed collector can significantly improve the hydrophobicity of the low-rank coal surface, which is beneficial for improving the floatability of coal particles. Flotation tests verified the theoretical and experimental results: when the mass ratio of dodecanoic acid was 40%, the combustible matter recovery was significantly increased compared to that using a single collector. Consequently, the addition of a polar component reduces the required dosage of the traditional oily collector. This investigation provides a better understanding of the interaction mechanism of mixed collectors in low-rank coal flotation.

MicroRNA gene polymorphisms and the risk of colorectal cancer.

The present study was carried out to demonstrate the epidemiological value of microRNA (miRNA) in colorectal cancer (CRC) by investigating the association between miRNA gene polymorphisms and the susceptibility to CRC. Multiple meta-analyses of reported data were conducted, and odds ratio values and 95% confidence intervals were used to assess these associations. Stata 11.0 software was used to analyze the data and the modified Jadad quality score was employed to evaluate the quality of the retrieved studies. We retrieved 38 studies on the association between miRNA polymorphisms and risk of CRC, however only 15 met the requirements of the inclusion criteria. In conclusion, we identified a variety of miRNAs (miRNA-let-7, miR-34b/c, miR-146a, miR-603 and miR-149) gene polymorphisms that are associated with susceptibility to CRC. However, some miRNAs (miR-192a, miR-608 and miR-27a) are associated with CRC, but not susceptibility to CRC. The results have limitations given the relatively low number of studies available. Therefore, it is necessary to collect data from large sample-size studies to further validate the results.