Thermal Aging Degradation of High-Viscosity Asphalt Based on Rheological Methods.

With the acceleration of the construction of sponge cities in China, porous asphalt pavement (PA) is has been widely used. High-viscosity asphalt (HVA) is the core material in building PA because it has good rheology properties, which can provide good raveling and rutting resistance. However, due to the open-graded structure of PA, HVA was more susceptible to rapid aging, which significantly affects the durability of PA. To investigate the thermal aging effect on the rheological properties of self-modified HVA (SHVA), five types of asphalts were aged using a rolling thin film oven (RTFO) and pressure aging vessel (PAV). Then, rheological tests were adopted, such as temperature sweep test (TS), repeated creep and recovery test (RCR), and bending beam rheometer test (BBR). The results indicate that during the aging process, the oxidation-induced hardening effect of neat asphalt and the degradation-induced softening effect of the modifier changes the rheology properties of HVA significantly. As the aging progresses, the contribution of the modifiers of HVA to anti-aging performance is greatly reduced. At high temperatures, HVA demonstrates better anti-aging performance than conventional styrene-butadiene-styrene (SBS)-modified asphalt (Guo Chuang, GC). The change of the high-temperature rheological indices of the two HVA types (SHVA and TAFPACK-super HVA (TPS)) showed a smaller activation energy index (EAI), a more considerable viscous component of binder creep stiffness (Gv), and more minor accumulated stain (racc), indicating a more significant anti-short-term and long-term aging performance, which is beneficial to the high-temperature performance of asphalts. However, the changes in low-temperature rheological properties do not align with those in high-temperature rheological properties after long-term aging. The BBR test results reveal that TPS exhibits worse low-temperature performance than GC and SHVA. During the thermal aging process, the contribution rate of the modifiers in SHVA against RTFO and PAV aging is higher than that of the modifiers in TPS, which contributes to the superior anti-aging property. Overall, SHVA demonstrates the best anti-aging performance among the five asphalts tested.

Research on the Moisture Stability of Asphalt Mixtures with Three Solid Waste Fillers.

Widespread interest has been drawn to the use of solid waste fillers as a partial replacement for natural fillers in high-performance asphalt mixtures in recent years. However, variations in the material properties of solid waste fillers remain a problem for the recycling method. To address this issue, the limestone powder in asphalt mixtures was replaced with three solid waste fillers, including steel slag powder, tailings powder and calcium carbide slag powder in this study. The chemical composition of the fillers was first characterized to assess the homogeneity of the material. Then, a dense-graded asphalt mixture (AC) and a stone matrix asphalt (SMA) mixture were designed, produced and characterized for wet stability. The results show that the asphalt mixtures with solid waste fillers were superior to limestone powder (LP) asphalt mixtures in terms of resistance to water damage, and the steel slag powder showed the best improvement in moisture stability of the asphalt mixtures. The optimum substitution of solid waste filler for limestone filler was 25%. With the addition of anti-stripping agents, the moisture stability of the asphalt mixture with limestone filler was also greatly enhanced. On the contrary, a marginal enhancement was observed in the moisture stability of asphalt mixtures using solid waste fillers. Solid waste fillers can be used in asphalt mixtures and have a similar function as that of anti-stripping agents. In summary, the use of solid waste fillers to replace mineral fillers in asphalt mixtures is a reliable, value-added recycling option.

Effect of Fiber Reinforcement on Creep and Recovery Behavior of Cement-Emulsified Asphalt Binder.

In order to evaluate and improve the deformation behavior of cement-emulsified asphalt binder (CA) in cement-emulsified asphalt mixture, this study investigated the reinforcement of small additions of fibers (2%, 4%, and 6% addition by mass of cement) on the deformation resistance of CA. A repeated creep recovery test was implemented that measures the recovery rate of creep deformation and accumulated strain. Further, an improved piecewise curve-fitting method was used to determine the parameters of Burgers model, then the creep compliances were fitted and calculated. The results show the repeated creep recovery test to be a suitable method for obtaining useful information about creep and recovery deformation of fiber-reinforced CA. The influence of fiber types and dosages on the deformation recovery ability is determined based on the creep recovery ratio and accumulated strain. The improved piecewise curve-fitting method has high accuracy. Thereafter, the reinforcement effect was analyzed through the evolution of creep compliance under loading. Therefore, this paper can provide a reference for enhancing the properties of cement-emulsified asphalt mixture by maximizing the fiber reinforcement.

Neoadjuvant apatinib plus tegafur/gimeracil/oteracil potassium (S­1)/oxaliplatin chemotherapy vs. chemotherapy alone in patients with locally advanced gastric carcinoma.

The current study aimed to evaluate the efficacy and safety of neoadjuvant apatinib plus tegafur/gimeracil/oteracil potassium (S-1) plus oxaliplatin (SOX) chemotherapy in patients with locally advanced gastric carcinoma (LAGC). Therefore, patients with LAGC treated with neoadjuvant apatinib plus SOX chemotherapy (apatinib + SOX group; n=25) or SOX chemotherapy (SOX group; n=35) were enrolled in the present study. Subsequently, the objective response (ORR) and disease control rates (DCR), pathological response, disease-free survival (DFS), overall survival (OS) and adverse events were recorded. The results showed that patients in the apatinib + SOX group exhibited a higher ORR (64.0 vs. 37.1%; P=0.040), but a similar DCR (96.0 vs. 88.6%; P=0.580), compared with those in the SOX group. The pathological response rates in patients with grade 0, 1, 2 and 3 LAGC were 0.0, 20.8, 62.5 and 16.7%, respectively, in the apatinib + SOX group, while in those treated with SOX alone they were 9.1, 39.4, 42.4 and 9.1%, respectively. By contrast, the pathological response was elevated in the apatinib + SOX group compared with the SOX group (P=0.030). During a median follow-up period of 21.0 months (range, 6.4-38.1 months), median DFS and OS were not reached. More specifically, the 1-, 2- and 3-year DFS rates were 91.7, 75.2 and 75.2% in the apatinib + SOX group and 71.8, 59.6 and 44.7% in the SOX group, respectively. In addition, the 1-, 2- and 3-year OS rates were 100.0, 89.6 and 78.4% in the apatinib + SOX group, while those in the SOX group were 90.3, 69.2 and 55.4%, respectively. However, no differences in DFS (P=0.094) or OS (P=0.155) were observed between the two groups. Additionally, the most common adverse events in the SOX group were mild leukopenia (42.9%) and fatigue (34.3%), while those in the apatinib + SOX group were tolerable leukopenia (44.0%) and hypertension (44.0%). In conclusion, the present study suggested that neoadjuvant apatinib plus SOX chemotherapy could be more effective and tolerable compared with SOX chemotherapy alone in patients with LAGC.

Hydrogen sulfide-sensitive Chitosan-SS-Levofloxacin micelles with a high drug content: Facile synthesis and targeted Salmonella infection therapy.

The delivery system of antibiotics plays an important role in increasing the drug efficacy and reducing the risks of off-target toxicities and antibiotic resistance. The pathophysiology of bacterial infections is similar to that of tumor tissues, but only a few delivery systems have been able to target and release antibiotics on demand. Herein, we designed and developed a robust Chitosan-SS-Levofloxacin (CS-SS-LF) micelles for targeted antibiotic delivery, in which disulfide bond can be reduced by hydrogen sulfide (H2S), a typical product of Salmonella, and subsequently released antibiotic to eradicate Salmonella infection. CS-SS-LF micelles showed uniform size and sharp response to H2S. Compared with levofloxacin alone, these micelles possessed a better capacity in disrupting Salmonella biofilms and reducing bacterial burden in organs. The H2S-sensitive CS-SS-LF micelles might enable a new way to address bacterial infections.

Fiber-Reinforcing Effect in the Mechanical and Road Performance of Cement-Emulsified Asphalt Mixtures.

Cement-emulsified asphalt mixture (CEAM), a kind of cold mix asphalt mixture, has the advantages of energy conservation and emission reduction as well as easy construction. However, the performance of CEAM is not as good as hot mixed asphalt mixtures. Hence, in this study, two different fibers were adopted as the reinforcing phase to improve the comprehensive properties of CEAM. The results indicated that the addition proportion and curing time were crucial to fiber-reinforced cement-emulsified asphalt mixture (FRCEAM). The compressive strengths, water stability, and raveling resistances of FRCEAM preparations with polyester or brucite fibers (FRCEAM-PF and -BF, respectively) were enhanced significantly. FRCEAM-PF had the maximum flexural tensile strength and strain, which meant that its low-temperature performance was the best compared to FRCEAM-PF and CEAM. However, the contribution of PF to CEAM high-temperature stability was greater than that of BF. Fiber addition to CEAM not only enhanced the cycles of fatigue loading but also reduced sensitivity to changes in stress level. Furthermore, FRCEAM-BF durability was slightly better than that of FRCEAM-PF. SEM analysis indicated that fibers provided bridging and meshing effects. Although PF and BF showed different enhancement effects, both mixtures met the requirements for hot mixed asphalt mixtures.

Analysis of feasibility, safety and effectiveness of ultrasound-guided percutaneous microwave ablation of splenic neoplasm.

The present study aimed to analyze the feasibility, safety and effectiveness of ultrasound-guided percutaneous microwave ablation of splenic neoplasm. A total of 62 patients with splenic neoplasm admitted to Second People's Hospital of Liaocheng between January 2009 and December 2012 were selected, and randomly divided into the observation group (n=31) and control group (n=31). The control group was treated with open ablation, while the observation group was treated with ultrasound-guided percutaneous microwave ablation. The splenic hemodynamics and ablation effects of patients after treatment were detected via color Doppler ultrasound. The changes in peripheral blood cell count before treatment, and at 3, 7 and 14 days after treatment were monitored. The side effects and complications were compared between the two groups. Patients were followed up for 5 years to observe the survival rates of the two groups. At 1 week after treatment, the peak velocity of splenic artery in observation group was significantly lower than that in control group, and the diameter, velocity and flow of splenic vein were significantly lower than those in control group (P<0.05). After treatment, the white blood cell and platelet counts in both groups were significantly increased compared with those before treatment, and the counts in observation group were obviously higher than those in control group (P<0.05). There were no significant changes in the red blood cell counts in both groups before and after treatment (P>0.05). The ablation volume, ablation ratio and 1-week shrink ratio in both groups had no significant differences (P>0.05). The incidence rates of side effects and complications in observation group were significantly lower than those in control group (P<0.05). The 5-year survival rates of both groups were >50%, and the survival time and survival rate were not significantly different (P<0.05). The curative effects of open ablation and ultrasound-guided percutaneous microwave ablation in the treatment of splenic neoplasm were significant, and the 5-year survival rate of patients was higher; compared with open ablation. The ultrasound-guided percutaneous microwave ablation is characterized by the small trauma, lower incidence rates of adverse reactions and complications and better safety, which can increase the peripheral blood cell count, and improve the splenic blood flow and coagulation function, playing a role in the regulation of the patient's body status.

Correlation of circulating pro-angiogenic miRNAs with cardiotoxicity induced by epirubicin/cyclophosphamide followed by docetaxel in patients with breast cancer.

OBJECTIVE: This study aimed to evaluate predictive value of 14 pro-angiogenic miRNAs for cardiotoxicity induced by epirubicin/cyclophosphamide follow by docetaxel (EC-D) in breast cancer (BC) patients. METHODS: Three hundred and sixty-three BC patients receiving EC-D neoadjuvant chemotherapy were consecutively enrolled in this prospective cohort study. Peripheral blood sample was obtained from each patient, and plasma was separated. The expressions of 14 pro-angiogenic miRNAs, cardiac troponin I (cTnI) and N-terminal pro brain natriuretic peptide (NT-proBNP) were evaluated. Left ventricular ejection fraction (LVEF) level at C0, the end of 4 cycles of EC chemotherapy (C4), the end of 4 cycles of docetaxel treatment (C8), 3rd months (M3), 6th months (M6), 9th months (M9) and 12th months (M12) after surgery were assessed. RESULTS: LVEF decreased at C4, C8, M3, M6, M9 and M12 compared with C0, and the total cardiotoxicity incidence was 5.2%. Additionally, the levels of let-7f, miR-17-5p, miR-20a, miR-126, miR-210 and miR-378 were reduced in cardiotoxicity patients. Multivariate logistic regression revealed that miR-17-5p and miR-20a were independently predictive factors for less cardiotoxicity. Receiver operating characteristics (ROC) curve displayed a satisfactory predictive value for lower cardiotoxicity risk with area under curve (AUC) of 0.842 of the combination of the miR-17-5p and miR-20a expressions. In addition, let-7f,miR-126, miR-210 and miR-378 levels negatively correlated with cTnI expression, and let-7f and miR-130a expressions reversely correlated with NT-proBNP level.CONLUSIONS: miR-17-5p and miR-20a could be served as biomarkers for lower cardiotoxicity induced by EC-D neoadjuvant chemotherapy in BC patients.