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The prediction of asphalt mixture dynamic modulus (E*) was investigated based on 1128 E* measurements, using three regression and thirteen machine learning models. Asphalt binder properties and mixture volumetrics were characterized using the same feeding features in the NCHRP 1-37A Witczak model. However, three aggregate gradation characterization approaches were involved in both modelling techniques: the NCHRP 1-37A gradation parameters, Weibull distribution factors, and Bailey method parameters. This study evaluated the performance of these models based on various performance indicators, using both statistical and machine learning regression modeling techniques. K-fold cross-validation and learning curve analysis were conducted to assess the models' generalization capabilities. The conclusions of this study demonstrate the superiority of the ML models, particularly the Catboost ensemble learning regression (CbR). Hyperparameter optimization and residual analysis were performed to fine-tune and confirm the heteroscedasticity of the CbR model. The Bailey-based CbR model showed the highest coefficient of determination (R2) of 0.998 and the lowest root mean square error (RMSE) of 220 MPa. Moreover, SHAP values interpreted the CbR model and showed the relative importance of its feeding features. Based on the findings of this study, the CbR model is suggested to accurately predict E* for a variety of asphalt mixtures. This information can be used to improve pavement design and construction, leading to more durable and long-lasting pavements. [ABSTRACT FROM AUTHOR]

This research study aims to investigate the feasibility of incorporating high-density polyethylene waste (HDPEW) into bitumen applications. Two conventional conditions of bitumen, namely, aged bitumen (AB) and virgin bitumen (VB), are rejuvenated and modified, respectively, using post-consumer HDPEW sourced out of bottle crates. The outcome (Pyro oil, PO-HDPEW) of the pyrolysis thermochemical process is used by 10, 20, and 30% to rejuvenate AB, while the fine-ground granules (FG) (FG-HDPEW) are used by 2, 3, 4, and 5% to modify the VB with different percentages. Physical and rheological characterization testing, including penetration, softening point temperature, and rotational viscosity (RV), is conducted to evaluate the performance of the HDPEW-rejuvenated and -modified binders and optimize both rejuvenator and modifier percentages. In addition, physical and chemical tests, including scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and Fourier transform infrared spectroscopy (FTIR) are conducted to analyze the composition, distribution of surface contaminants, and the molecular structure of the bitumen, based on their respective wavelengths. Moreover, advanced mechanical and rheological tests, including dynamic shear rheometer (DSR), multiple stress creep and recovery (MSCR), and linear amplitude sweep (LAS) tests, are conducted to investigate the susceptibility of the rejuvenated and modified bitumen with HDPEW to rutting and fatigue cracking. The testing results demonstrate that the addition of PO-HDPEW to AB and FG-HDPEW modification of VB can enhance the physical, chemical, mechanical, and rheological properties of bitumen; however, this study recommends further research on the aging performance of the PO-HDPEW-rejuvenated bitumen. This research provides insights into using HDPEW as a cost-effective and eco-friendly rejuvenator and modifier on bitumen properties, which can aid in the longevity and performance of pavements. [ABSTRACT FROM AUTHOR]

Acute lymphoblastic leukemia (ALL) is the most common malignancy in children and young adults. Treatment is long and involves 2–3 years of a prolonged maintenance phase composed of oral chemotherapies. Adherence to these medications is critical to achieving good outcomes. However, adherence is difficult to determine, as there is currently no consensus on measures of adherence or criteria to determine nonadherence. Furthermore, there have been few studies in pediatric B-ALL describing factors associated with nonadherence. Thus, we performed a systematic review of literature on oral chemotherapy adherence during maintenance therapy in ALL following PRISMA guidelines. Published studies demonstrated various objective and subjective methods of assessing adherence without generalizable definitions of nonadherence. However, the results of these studies suggested that nonadherence to oral maintenance chemotherapy was associated with increased risk of relapse. Future studies of B-ALL therapy should utilize a uniform assessment of adherence and definitions of nonadherence to better determine the impact of nonadherence on B-ALL outcomes and identify predictors of nonadherence that could yield targets for adherence improving interventions. [ABSTRACT FROM AUTHOR]

Sickle-cell disease (SCD) is an inherited hemoglobinopathy, causing lifelong complications such as painful vaso-occlusive episodes, acute chest syndrome, stroke, chronic anemia, and end-organ damage, with negative effects on quality of life and life expectancy. Within the last five years, three new treatments have been approved: L-glutamine in 2017 and crizanlizumab and voxelotor in 2019. We conducted a literature search of these three medications, and of the 31 articles meeting inclusion criteria, 6 studied L-glutamine, 9 crizanlizumab, and 16 voxelotor. Treatment with L-glutamine was associated with decrease in pain crises, hospitalizations, and time to first and second crises, with a decrease in RBC transfusion rate. Barriers to filling and taking L-glutamine included insurance denial, high deductible, and intolerability, especially abdominal pain. Crizanlizumab was associated with a reduction in pain crises and time to first crisis, with reduction in need for opioid use. Adverse effects of crizanlizumab include headache, nausea, insurance difficulty, and infusion reactions. Voxelotor was associated with increased hemoglobin and decreased markers of hemolysis. Barriers for voxelotor use included insurance denial and side effects such as headache, rash, and diarrhea. These three medications represent exciting new therapies and are generally well-tolerated though price and insurance approval remain potential barriers to access. Other studies are ongoing, particularly in the pediatric population, and more real-world studies are needed. The objective of this article is to evaluate post-approval studies of crizanlizumab, voxelotor, and L-glutamine in SCD, with a focus on real-world efficacy, side effects, and prescribing data. [ABSTRACT FROM AUTHOR]

One of the main difficulties with employing recycled asphalt pavement (RAP) in hot mix asphalt (HMA) is bitumen aging; hence, the percentage of RAP in the HMA is limited. This research evaluates the rheological properties of the RAP binder and the performance of HMA containing high RAP content using waste engine oil (WEO) from an Electrical Power Plant as a rejuvenator. The rheological and microstructural properties of the RAP binder and rejuvenated RAP binder were determined in the laboratory. Both the recycled and rejuvenated recycled mixes were tested for Marshall stability, indirect tensile strength, dynamic modulus (E*), and flow number tests. The RAP binder was recovered using two different processes: rotavapor distillation followed by centrifugation (RCRD) and column distillation without centrifugation (RNCCD). The optimal WEO percentages for the RCRD and RNCCD recovery procedures were 0.5% and 3%, respectively. The Marshall test results revealed that adding WEO to the recycled mix enhanced its stability and flow compared to the control mix. The rejuvenated mix containing recovered binder from the RCRD recovery process was found to be better than the rejuvenated mix containing recovered binder from the RNCCD recovery process. The rejuvenated recycled mixes outperformed the recycled mix in terms of moisture resistance, which was evidenced by tensile strength ratio values of 0.88, 0.90, and 0.91 for the control and 0.5% and 3% WEO modified mixes, respectively. Finally, the results of dynamic modulus and flow number testing revealed that the rejuvenated mixes had a modest drop in both the dynamic modulus and flow number compared to the non-rejuvenated mix. [ABSTRACT FROM AUTHOR]

This paper examines the transferability of the Safety Performance Function (SPF) of the Highway Safety Manual (HSM) and other 10 international SPFs for total crashes on rural multi-lane divided roads in Egypt. Four segmentation approaches are assessed in the transferability of the international SPFs, namely: (1) one-kilometer segments (S1); (2) homogenous sections (S2); (3) variable segments with respect to the presence of curvatures (S3); and (4) variable segments with respect to the presence of both curvatures and U-turns (S4). The Mean Absolute Deviation (MAD), Mean Prediction Bias (MPB), Mean Absolute Percentage Error (MAPE), Pearson χ² statistic, and Z-score parameters are used to evaluate the performance of the transferred models. The overdispersion parameter (k) for each transferred model and each segmentation approach is recalibrated using the local data by the maximum likelihood method. Before estimating the transferability calibration factor (Cr), three methods were used to adjust the local crash prediction of the transferred models, namely: (1) the HSM default crash modification factors (CMFs); (2) local CMFs; and (3) recalibrating the constant term of the transferred model. The latter method is found to outperform the first two methods. Besides, the results show that the segmentation method would affect the performance of the transferability process. Moreover, the Italian SPFs based on the S1 segmentation method outperforms the HSM and all of the investigated international SPFs for transferring their models to the Egyptian rural roads. [ABSTRACT FROM AUTHOR]

Flexible pavement structure design is a complex task because of the variability of design input parameters and complex failure mechanisms. Therefore, the aim of this study is to develop and implement a simplified Mechanistic-Empirical (M-E) pavement design method based on the 1993 American Association of State Highway and Transportation Officials (AASHTO), the National Cooperative Highway Research Program (NCHRP) 9-22, and NCHRP 1-37A and 1-40D projects. This simplified methodology is implemented into a computer code and a user-friendly software called "ME-PAVE". In this methodology, only two equivalent temperatures, as per the NCHRP 9-22 project, are estimated to adjust the dynamic modulus of the asphalt layer(s) for Asphalt Concrete (AC) rutting and AC fatigue cracking prediction instead of using the hourly climatic data, as in the AASHTOWare Pavement ME. In ME-PAVE, the structural responses at critical locations in the pavement structure are determined by a Finite Element Module (FEM), which is verified by a Multi-layer Elastic Analysis (MLEA) program. To ensure that the simplified methodology is practical and accurate, the incorporated transfer functions in the proposed simplified methodology are calibrated based on the Long-Term Pavement Performance (LTPP) data. Based on statistical analyses, the built-in FEM results exhibit very similar trends to those yielded by MLEA, with a coefficient of determination, R2 of 1.0. For all practical purposes, the proposed methodology, despite all simplifications, yields acceptable prediction accuracy with R2 of 0.317 for the rut depth compared to the current practices, NCHRP 1-37A and 1-40D (R2 = 0.399 and 0.577, respectively); while the prediction accuracy for fatigue cracking with R2 of 0.382 is comparable to the NCHRP 1-40D with R2 of 0.275. Nonetheless, the standard error for both distresses is in good agreement based on the investigated data and the developed methodology. Finally, the conducted sensitivity analysis demonstrate that the proposed methodology produces rational pavement performance. [ABSTRACT FROM AUTHOR]