A comprehensive review on polyurethane modified asphalt: Mechanism, characterization and prospect

Polyurethane(PU),with excellent physical and chemical properties and high designability,is one of the ideal materials for asphalt modification in the future.In this paper,based on the limitations of traditional asphalt modifiers,the preparation process,relative advantages and development prospects of PU as asphalt modifiers are described.Subsequently,the spatial structure,physical and chemical properties of PU synthetic raw materials were combined with the modification properties of PU to analyze the effect and influence of PU on asphalt modification.Specifically,polyurethane modified asphalt(PUMA)is divided into thermoplastic polyurethane modified asphalt(TP-PUMA)and thermosetting polyurethane modified asphalt(TS-PUMA).The gain effect of TPPUMA in high-temperature performance,low-temperature performance,aging resistance,fatigue resistance,weathering performance and bonding performance is obvious.In addition,it has good storage stability.With excellent road performance,TS-PUMA makes up for the shortcomings of epoxy asphalt in terms of lowtemperature performance and compatibility.Finally,due to the development trend of functional diversification of modified asphalt,the research basis and status of several new modified asphalts based on PU properties are described.Because the systematic study of PUMA is insufficient,this paper proposes corresponding research.To provide guidance and ideas for the research of PU modified asphalt.

Nomogram based on albumin-bilirubin grade to predict outcome of the patients with hepatitis C virus-related hepatocellular carcinoma after microwave ablation

Objective:To construct a nomogram based on the albumin-bilirubin(ALBI)grade to provide prognostic value for hepatitis C virus(HCV)-related hepatocellular carcinoma(HCC)patients who underwent ultrasound-guided percutaneous microwave ablation(US-PMWA).Methods:From April 2005 to January 2018,183 treatment-naIve patients with 251 HCV-related HCCs according to the Milan criteria received US-PMWA subsequently.The overall survival(OS)and recurrence-free survival(RFS)were compared between groups classified by ALBI grade.Cox proportional hazard regression model based on risk factors for survival and recurrence was used to construct the nomogram.Results:The cumulative OS rates at 1-,3-,5-and 10-year were 97.7%,73.6%,54.5%and 34.5%,respectively.Stratified according to ALBI grade,the 1-,3-,and 5-year OS in the ALBI grade 1 group and grade 2 group were 99.2%,92.4%,77.9% and 97.7%,52.3%,38.6%,respectively,with significant statistical difference(P<0.001).No significant statistical difference was detected in the1-,3-,and 5-year RFS rates in the ALBI grade 1 group and grade 2 group(P=0.220).The major complication rate was 1.6%.Multivariate analysis results showed age,α-fetoprotein level,tumor number,platelet count,location,Child-Turcotte-Pugh(CTP)and ALBI grade were associated with OS,which generated the nomograms.Internal validation with 1000 bootstrapped sample sets had good concordance index of 0.769(95%CI 0.699-0.839)in OS.Conclusions:This nomogram based on ALBI grade was a visualization risk model,which could provide personalized prediction of long-term outcomes for HCV-related HCC patients after US-PMWA.

Cholecystectomy is associated with higher risk of recurrence after microwave ablation of hepatocellular carcinoma:a propensity score matching analysis

Objective:To explore the association between cholecystectomy and the prognostic outcomes of patients with hepatocellular carcinoma(H CC)who underwent microwave ablation(MWA).Methods:Patients with HCC(«=921)who underwent MWA were included and divided into cholecystectomy(n=114)and non-cholecystectomy groups(n=807).After propensity score matching(PSM)at a 1:2 ratio,overall survival(OS)and disease-free survival(DFS)rates were analyzed to compare prognostic outcomes between the cholecystectomy(«=114)and non-cholecystectomy groups(n=228).Univariate and multivariate Cox analyses were performed to assess potential risk factors for OS and DFS.Major complications were also compared between the groups.Results:After matching,no significant differences between groups were observed in baseline characteristics.The 1-,3-,and 5-year OS rates were 96.5%,82.1%,and 67.1%in the cholecystectomy group,and 97.4%,85.2%,and 74.4%in the non-cholecystectomy group(P=0.396);the 1-,3-,and 5-year DFS rates were 58.4%,34.5%,and 26.6%in the cholecystectomy group,and 73.6%,44.7%,and 32.2%in the non-cholecystectomy group(P=0.026),respectively.The intrahepatic distant recurrence rate in the cholecystectomy group was significantly higher than that in the non-cholecystectomy group(P=0.026),and the local tumor recurrence and extrahepatic recurrence rates did not significantly differ between the groups(P=0.609 and P=0.879).Multivariate analysis revealed that cholecystectomy(HR=1.364,95%Cl 1.023-1.819,P=0.035),number of tumors(2 vs.1:HR=2.744,95%Cl 1.925-3.912,P<0.001;3 vs.1:HR=3.411,95%Cl 2.021-5.759,P<0.001),and y-GT levels(HR=1.003,95%Cl 1.000-1.006,P<0.024)were independent risk factors for DFS.The best y-GT level cut-off value for predicting median DFS was 39.6 U/L(area under the curve=0.600,P<0.05).A positive correlation was observed between cholecystectomy and y-GT level(r=0.108,95%Cl-0.001-0.214,P=0.047).Subgroup analysis showed that the DFS rates were significantly higher in the non-cholecystectomy group than the cholecystectomy group when Y-GT>39.6 U/L(i3=0.044).The 5-,10-,15-,20-,and 25-year recurrence rates from the time of cholecystectomy were 2.63%,21.93%,42.11%,58.77%,and 65.79%,respectively.A significant positive correlation was observed between cholecystectomy and the time from cholecystectomy to recurrence(r=0.205,95%Cl 0.016-0.379,P=0.029).There were no significant differences in complications between groups(P=0.685).Conclusions:Patients with HCC who underwent cholecystectomy were more likely to develop intrahepatic distant recurrence after MWA,an outcome probably associated with increased y-GT levels.Moreover,the recurrence rates increased with time.

Microwave ablation vs. surgical resection for treatment naïve hepatocellular carcinoma within the Milan criteria: a follow-up of at least 5 years

Objective:Thermal ablation poses challenges in the surgical resection(SR)of small hepatocellular carcinoma(HCC),and its therapeutic outcomes for larger lesions remain debated.Methods:This retrospective study evaluated 729 patients with HCC meeting the Milan criteria,who were treated with curative SR or microwave ablation(MWA)between 2008 and 2014.Overall survival(OS),cancer-specific survival(CSS),disease-free survival(DFS),and local tumor progression(LTP)were compared after propensity score matching(PSM).Co-variates associated with OS,CSS,LTP,and DFS were identified.The risk of death and tumor progression were compared.Results:During the median follow-up of 78.6 months,253 patients were included in each group after PSM.For tumors≤3.0 cm and 3.1–4.0 cm,MWA achieved comparable results in terms of OS,CSS,DFS,and LTP.For tumors 4.1–5.0 cm,MWA had lower OS,CSS,and DFS rates(all P<0.05)than SR.Higher LTP rates were observed in the MWA group for tumors 4.1–5.0 cm,although the difference was not significant(P=0.18).Complication rates(P=0.41)were similar,but MWA led to less estimated blood loss(P<0.01)and shorter postoperative hospitalization times(P<0.01).Conclusions:MWA achieved comparable long-term oncologic outcomes with SR for≤4 cm HCC,with lower complication rates and faster recovery.

Parametrization of woods-saxon potential for heavy-ion systems

Several elastic scattering angular distributions of ^(12)C from target nuclei of A ≥39 are analyzed to extract the Woods-Saxon potential parameters with the fixed imaginary potential and Coulomb radius parameters.Using the best fitted diffuseness parameters,the correlations of the real part parameters with A_1^(1/3)+ A_2^(1/3) and incident energy are revealed, and the systematic Woods-Saxon potential parameters are presented for nucleus-nucleus interaction.The proposed potential parameters can reproduce not only the elastic scattering angular distributions induced by ^(12)C,but also many elastic scattering angular distributions induced by the projectiles other than ^(12)C,thus providing important inputs for the study of nuclear reactions of heavy-ion systems.

Empirical formula for β^--decay half-lives of r-process nuclei

Experimental data ofβ--decay half-lives of nuclei with atomic number between 20 and 190 are investigated.A systematic formula has been proposed to calculateβ^--decay half-lives of neutron-rich nuclei,with a particular consideration on shell and pair effects,the decay energy Q as well as the nucleon numbers(Z,N).Although the formula has relatively few parameters,it reproduces the experimentalβ^--decay half-lives of neutron-rich nuclei very well.The predicted half-lives for the r-process relevant nuclei obtained with the current formula serve as reliable input in the r-process model calculations.

Microscopic experimental and numerical research on rejuvenators: A review

Prompting high content of reclaimed asphalt pavement(RAP) to be used in road building and maintenance has drawn great attention. The application of rejuvenators is an efficient way to ensure the performance of recycled asphalt mixtures. However, as various types of rejuvenators emerging, limited understanding about rejuvenation poses challenges to put effective ones into use. For precisely evaluating the performance of rejuvenators, plenty of studies were conducted to ascertain the fundamental mechanism of rejuvenating from the microscopic view. This paper provides an overview of studies focusing on the change inside asphalt after adding rejuvenators. Chemical compositions of rejuvenators were collected as basic information. Both laboratorial experiments and molecular dynamic simulations were investigated to not only compare the effectiveness of several rejuvenators but also explain the rejuvenating mechanism. Finally, functional groups of rejuvenator structures were comprehensively examined to provide global understanding about how chemical compositions influence the efficacy of rejuvenators. This review highlights that the essential capacity of a true rejuvenator is to disturb asphaltene agglomerations. Besides, the molecular structures of rejuvenators will not only affect their deagglomerating abilities but also the performances of diffusion and durability. It has been found that gel-permeation chromatography(GPC) analysis is effective in evaluating the performance of rejuvenators, while Fourier transform infrared spectroscopy(FT-IR) and SARA(saturates, aromatics, resins and asphaltenes) analysis are only suitable for assessing asphalt oxidization. In addition, comparing some tests can only detect changes, molecular dynamic simulation can reveal the mechanism both of data and vision. The results of this work can provide comprehensive knowledge for the evaluation and development of rejuvenators.