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• Waste cooking and engine oils (WCO, WEO) were investigated as bitumen rejuvenators. • Optimum percentages of the waste oils were 3.5% for the WCO and 5.5% for the WEO. • Rejuvenated bitumen showed less tendency to short-term aging based on DSR results. • Rejuvenated bitumen by both WCO and WEO had a performance grade of PG 64-28. • Rejuvenated 100% RAP mixes cope with Egyptian limits for stability, flow, and ITS. For sustainable pavement construction, this research paper aims to investigate the feasibility of using Waste Cooking Oil (WCO) and Waste Engine Oil (WEO) as rejuvenators on the rheological properties of aged bitumen extracted from Reclaimed Asphalt Pavement (RAP). The aged bitumen was extracted from milled RAP recruited from an old pavement. The rheological characteristics of the rejuvenated bitumen were determined by penetration, softening point, Brookfield viscosity, Dynamic Shear Rheometer (DSR), and Bending Beam Rheometer (BBR) tests. In addition, the chemical composition of virgin (control), aged and rejuvenated bitumen by WCO, and WEO was investigated using Fourier Transform Infrared Spectroscopy (FTIR) and Energy Dispersive X-ray (EDX). The quality of the rejuvenated bitumen was also evaluated by the Scanning Electron Microscopy (SEM) imaging technique. Based on penetration and softening point testing results, the optimum percentages of the waste oils were found to range from 3.5 to 4.0% for the WCO and from 5.5 to 6.0% for the WEO. The aged bitumen properties were significantly improved by rejuvenators as evidenced by the chemical analysis (FTIR and SEM/EDX) along with the ratio of asphaltenes to maltenes. Furthermore, the surface morphology was renovated as well as the fundamental physical properties of the rejuvenated aged bitumen. Additionally, the rejuvenated bitumen showed less tendency to short-term aging as confirmed by the DSR results. BBR results of rejuvenated aged bitumen samples exhibited comparable performance to those of the control samples at different low temperatures having a performance grade of PG 64-28. Moreover, rejuvenated 100% RAP mixes were found to cope with Egyptian requirements for heavy traffic as binder courses and medium traffic as wearing courses in terms of Marshall stability and flow. Finally, Indirect Tensile Strength (ITS) results were within the specification limits. [ABSTRACT FROM AUTHOR]

International Roughness Index (IRI) is an important pavement performance indicator that is widely used to reflect existing pavement condition and ride quality. Due to the importance of this significant index, the current research aims to develop a precise IRI prediction model using the Gaussian Process Regression (GPR) and Locally Weighted Polynomials (LWP). The long-term pavement performance (LTPP) datasets of pavement age, initial IRI, alligator, longitudinal and transverse cracks, standard deviation of rutting, and subgrade plasticity index variables are employed in predicting IRI. These datasets are collected from 126 different flexible pavement sections of the LTPP specific pavement studies (SPS-1) located in different climatic zones in the US. The total number of IRI measurements in the collected database is 925 which covers a wide range of IRI values. Multiple linear regression (MLR) is firstly applied to classify the input variables. Then the MLR model is compared with four machine learning techniques which are GPR, LWP, Particle Swarm Optimization-Adaptive Network based Fuzzy Inference System (PSO-ANFIS) and PSO-Artificial Neural Networks (PSO-ANN). The developed models' performance is validated using different statistical indices, including the coefficient of determination (R 2). The results demonstrate that the GPR ( R 2 = 0. 93) and LWP ( R 2 = 0. 90) outperformed the PSO-ANFIS ( R 2 = 0. 65) and PSO-ANN ( R 2 = 0. 52) in predicting IRI. Thus, the GPR model is found to be more accurate for IRI modeling compared to the hybrid investigated models. [ABSTRACT FROM AUTHOR]

Highlights: [•] NCHRP1-37A yielded better E * values compared to NCHRP 1-40D model at all binder characterization input levels. [•] NCHRP1-37A E * model with Level 3 binder characterization produced the most accurate and the least biased estimates. [•] Because of the hot desert climate in KSA, care should be taken when using such models for E * predictions. [Copyright &y& Elsevier]

• SEA modified with rPE is sustainable, economic, and ecofriendly alternative. • rPE made SEA stiffer/elastic thus better resistance to rutting/fatigue cracking. • Addition of rPE to SEA improved elastic and viscous properties. This research evaluates the rheological properties of virgin asphalt and sulfur extended asphalt (SEA) modified with two types of recycled plastic waste (rPW). The investigated plastic wastes are the recycled low-density polyethylene (rLDPE) and recycled high-density polyethylene (rHDPE). It also assesses the environmental and economic benefits of recycling such materials. A total of 16 modified binder samples are produced by adding rLDPE and rHDPE modifiers to virgin asphalt and SEA in four different concentrations of 2%, 4%, 6%, and 8% by weight of asphalt. The basic and rheological properties of the virgin and modified asphalts are explored by conventional tests, and advanced rheological tests at different aging conditions. Finally, cost-effectiveness and environmental analyses are conducted. The environmental benefit analysis is performed by comparing carbon and non-methyl volatile organic compound (NMVOC) emission from the various recycled polyethylene (rPE) with the manufacturing process of the same quantities of virgin LDPE and HDPE when used to modify asphalt. The effect of incorporating sulfur into virgin asphalt on the environment is also determined. Results show that modification yields a higher binder complex shear modulus (G*) and a lower loss tangent (tan δ) at all traffic speeds meaning improved rut resistance behavior under heavy traffic loading and high temperature conditions. About 29% reduction in material cost occurs when rPE-modified SEA is used instead of virgin asphalt. The environmental and economic analyses show that using SEA modified with rPE for road construction is an economic, sustainable, and ecological alternative with better performance compared to virgin asphalt. [ABSTRACT FROM AUTHOR]

Successful maintenance of a heart transplant (HTx) graft requires adherence to a triple-drug regimen of immunosuppression. However, achieving adequate adherence can be difficult secondary to complicated dosing regimens, side effects, and mental/emotional barriers. A detailed review of current patterns of adherence to immunosuppression in adult HTx recipients is lacking. This systematic review aims to detail the current landscape of adherence to immunosuppression in adult heart transplant patients, including the measurement of adherence, correlates to adherence, health outcomes associated with nonadherence, as well as strategies to improve adherence in HTx patients. We conducted searches in PubMed MEDLINE, Embase, CENTRAL register of Controlled Trials (Wiley), and Scopus, from inception to March 2020. Studies were eligible if they outlined an aspect of adherence (as noted above in the objective) to immunosuppression in adult HTx patients. The HTx cohort had to contain at least 10 patients and measurement of adherence had to be done with an objective or otherwise validated measure of adherence (e.g. drug levels, automated pill bottles or adherence questionnaires). Two authors independently screened the articles for inclusion, then subsequently reviewed the full texts of the included articles. Data was extracted into standardized forms and bias evaluations were done using the Newcastle-Ottawa or modified Newcastle-Ottawa tools, depending on the study type. The authors followed all guidelines for the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The titles/abstracts of 880 articles were reviewed. Ultimately, 23 articles were included in the final review. The median number of participants was 101, with a range of 19 to 1397. Studies provided information on baseline levels of adherence (17 studies), correlates to adherence (14 studies), health outcomes related to nonadherence (3 studies) and interventions to improve adherence (3 studies). Baseline adherence estimates varied greatly depending on the adherence measure. Multiple significant correlates to nonadherence exist and appear to affect patients with certain sociodemographic backgrounds, those with psychological/psychiatric comorbidities and those with poor support structures. Nonadherence is associated with transplant coronary artery disease and acute late rejection; it may also be associated with long-term mortality. Finally, a simplified dosing regimen with once-a-day tacrolimus as well as use of a mobile phone-based intervention were associated with improved adherence. Bias scores were most deficient due to self-reported outcomes in 18 studies, and lack of controls/adjustments for confounders, in 7 studies. Adherence to immunosuppression in transplant patients varies, but is associated with observable and modifiable factors which are worth addressing. Further high-quality studies regarding strategies to improve adherence are needed in the literature. • Adherence to immunosuppression in heart transplant patients varies considerably. • Socio-demographics, mental health, and poor support correlate with nonadherence. • Nonadherence may lead to coronary artery disease and acute late rejection. • Simplified dosing regimen and a mobile app intervention were associated with improved adherence. [ABSTRACT FROM AUTHOR]

Highlights • New resilient modulus master surface approach was developed. • The approach characterizes both granular pavement materials and subgrade soils. • The approach considers the effect of stress state and moisture content levels. • The proposed master surface-2018 model produces accurate predictions. Abstract Resilient modulus is a fundamental material property used for pavement materials characterization. A new methodology for predicting the resilient modulus of unbound/stabilized pavement materials and subgrade soils is developed based on a master surface function at a reference water content. The resilient modulus measurements at different levels of water content are shifted horizontally with respect to the octahedral shear stress, and bulk normal stress; simultaneously. A total of 2754 resilient modulus laboratory measurements, obtained from literature, for five granular base materials, four subgrade soils, one recycled crushed concrete material, and three cement-treated stabilized fine materials are used to evaluate the proposed Master Surface model for the resilient modulus prediction as a function of the stress state, and water content. The proposed predictive methodology is compared to well-known models from literature. The comparison of the investigated models exhibits that the Master Surface model has the most precise and unbiased predictions after numerically optimizing the resilient modulus data. [ABSTRACT FROM AUTHOR]

Currently, sustainable pavement research focuses on modified asphalt binders with self-healing features for achieving durability and safety goals. This study assesses the self-healing behavior of asphalt binders incorporating innovative lab-manufactured hybrid-structured phase change material capsules (HPCMC). The HPCMC, using by-product paraffin oil as a core encapsulated by waste nano-silica fume as a shell, varied in core-to-shell ratios (0.5:1, 1:1, 2:1) and dosages (1 %, 3 %, 5 %, 7 %) by asphalt weight. Morphological, thermal, and chemical characterizations were conducted using scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermal gravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FTIR). Healing efficiency of unaged and short-term aged HPCMC-modified binders was evaluated using SEM and energy dispersive X-ray (EDX) for morphological and chemical analysis. Rheomechanics were examined through rotational viscosity (RV), performance grading (PG), multiple stress creep recovery (MSCR), strain sweep (SS), frequency sweep (FS), linear amplitude sweep (LAS), and linear amplitude sweep-based healing (LASH). Study findings exhibit superior healing in HPCMC-modified binders compared to unmodified ones, particularly at a 3 % dosage and 1:1 core-to-shell ratio in unaged conditions. This study also evaluates healing assessment criteria and validates the self-healing mechanism, indicating significant potential for the proposed approach to revolutionize pavement construction and maintenance. [Display omitted] • Innovative and sustainable self-healing approach through the incorporation of HPCMC to enhance asphalt binder durability. • Synthesis and characterization of HPCMC through morphological analysis, thermal stability, and chemical investigations. • Evaluation of rheomechanical performance and healing efficiency of HPCMC-modified asphalt binders under varied aging states. • Optimization of core-to-shell ratios and HPCMC dosages to maximize healing efficiency and rheomechanical performance. • Validation of self-healing mechanism, proving HPCMC's ability to repair microcracks and boost pavement quality. [ABSTRACT FROM AUTHOR]

Objectives: Discrete choice experiments (DCEs) are increasingly used to elicit preferences for health and healthcare. Although many applications assume preferences are homogenous, there is a growing portfolio of methods to understand both explained (because of observed factors) and unexplained (latent) heterogeneity. Nevertheless, the selection of analytical methods can be challenging and little guidance is available. This study aimed to determine the state of practice in accounting for preference heterogeneity in the analysis of health-related DCEs, including the views and experiences of health preference researchers and an overview of the tools that are commonly used to elicit preferences.Methods: An online survey was developed and distributed among health preference researchers and nonhealth method experts, and a systematic review of the DCE literature in health was undertaken to explore the analytical methods used and summarize trends.Results: Most respondents (n = 59 of 70, 84%) agreed that accounting for preference heterogeneity provides a richer understanding of the data. Nevertheless, there was disagreement on how to account for heterogeneity; most (n = 60, 85%) stated that more guidance was needed. Notably, the majority (n = 41, 58%) raised concern about the increasing complexity of analytical methods. Of the 342 studies included in the review, half (n = 175, 51%) used a mixed logit with continuous distributions for the parameters, and a third (n = 110, 32%) used a latent class model.Conclusions: Although there is agreement about the importance of accounting for preference heterogeneity, there are noticeable disagreements and concerns about best practices, resulting in a clear need for further analytical guidance. [ABSTRACT FROM AUTHOR]

• Recycled Plastic Waste (RPW) improved virgin (VA) & sulfur extended asphalt (SEA). • RPW made VA&SEA stiffer/elastic thus better resistance to rutting/fatigue cracking. • Addition of RPW to VA&SEA slowed the oxidation reactions of the binder. • Addition of RPW to VA&SEA made binder more suitable for wider range of temperature. • The modification effect of RPW on asphalt included chemical and physical processes. This study examines the effect of two different recycled plastic waste (RPW) which are high and low-density polyethylene (RHDPE and RLDPE) on the rheological/viscoelastic characteristics and aging performance of virgin asphalt and sulfur extended asphalt (SEA). Four dosages of the RPW additives representing 2%, 4%, 6%, and 8% by weight of the asphalt binder were investigated. The rheological characteristics of the RPW modified binders (virgin and SEA) are characterized at original and short-term aging conditions through the Rotational Viscometer (RV) and dynamic shear rheometer (DSR) tests. Fatigue performance is also characterized at the long-term aging condition. Also, high-temperature performance, dynamic storage stability (DSS), multiple stress creep and recovery (MSCR) are studied. Testing results show that RPWs lead to improved rutting and fatigue performance. Adding RPW to the virgin and SEA binders slows the binder oxidation reactions during the short-term aging. The Aging Index (AI) is found to be dependent on the asphalt rheological properties, amount/type of RPW, binder type, and temperature. RHDPE leads to an unstable modified virgin asphalt. Less than 4% RHDPE or 8% RLDPE with virgin asphalt show good DSS in terms of degradation and separation. The RPW with SEA meets the requirement of time degradation and separation set by the Federal Highway Administration (FHWA). The temperature susceptibility of asphalt binder decreases dramatically with the RPW modification making the asphalt binder more suitable for use at a wider range of temperatures. [ABSTRACT FROM AUTHOR]

Highlights • Late fatal infection (LFI) contributed to one-third of the deaths in both adult and pediatric hematopoietic cell transplantation (HCT) recipients surviving to 2 years post-HCT. • In adults age ≥20 years, receipt of matched unrelated donor (MUD) or mismatched unrelated donor (MMUD) HCT and male sex were associated with an increased risk of LFI. • In pediatric subjects, age ≥10 years, receipt of MUD or MMUD HCT, and inherited abnormalities of erythrocyte function were associated with an increased risk of LFI. ABSTRACT We analyzed late fatal infections (LFIs) in allogeneic stem cell transplantation (HCT) recipients reported to the Center for International Blood and Marrow Transplant Research. We analyzed the incidence, infection types, and risk factors contributing to LFI in 10,336 adult and 5088 pediatric subjects surviving for ≥2 years after first HCT without relapse. Among 2245 adult and 377 pediatric patients who died, infections were a primary or contributory cause of death in 687 (31%) and 110 (29%), respectively. At 12 years post-HCT, the cumulative incidence of LFIs was 6.4% (95% confidence interval [CI], 5.8% to 7.0%) in adults, compared with 1.8% (95% CI, 1.4% to 2.3%) in pediatric subjects; P <.001). In adults, the 2 most significant risks for developing LFI were increasing age (20 to 39, 40 to 54, and ≥55 years versus 18 to 19 years) with hazard ratios (HRs) of 3.12 (95% CI, 1.33 to 7.32), 3.86 (95% CI, 1.66 to 8.95), and 5.49 (95% CI, 2.32 to 12.99) and a history of chronic graft-versus-host disease GVHD (cGVHD) with ongoing immunosuppression at 2 years post-HCT compared with no history of GVHD with (HR, 3.87; 95% CI, 2.59 to 5.78). In pediatric subjects, the 3 most significant risks for developing LFI were a history of cGVHD with ongoing immunosuppression (HR, 9.49; 95% CI, 4.39 to 20.51) or without ongoing immunosuppression (HR, 2.7; 95% CI, 1.05 to 7.43) at 2 years post-HCT compared with no history of GVHD, diagnosis of inherited abnormalities of erythrocyte function compared with diagnosis of acute myelogenous leukemia (HR, 2.30; 95% CI, 1.19 to 4.42), and age >10 years (HR, 1.92; 95% CI, 1.15 to 3.2). This study emphasizes the importance of continued vigilance for late infections after HCT and institution of support strategies aimed at decreasing the risk of cGVHD. [ABSTRACT FROM AUTHOR]

Highlights • Remission at second transplantation extends survival. • The same donor preferred for both transplantations. • Mismatched cord blood should be avoided for a second transplantation. ABSTRACT Children with acute leukemia who relapse after hematopoietic cell transplantation (HCT) have few therapeutic options. We studied 251 children and young adults with acute myelogenous or lymphoblastic leukemia who underwent a second HCT for relapse after their first HCT. The median age at second HCT was 11 years, and the median interval between first and second HCT was 17 months. Most of the patients (n = 187; 75%) were in remission, received a myeloablative conditioning regimen (n = 157; 63%), and underwent unrelated donor HCT (n = 230; 92%). The 2-year probability of leukemia-free survival (LFS) was 33% after transplantation in patients in remission, compared with 19% after transplantation in patients not in remission (P =.02). The corresponding 8-year probabilities were 24% and 10% (P =.003). A higher rate of relapse contributed to the difference in LFS. The 2-year probability of relapse after transplantation was 42% in patients in remission and 56% in those in relapse (P =.05). The corresponding 8-year probabilities were 49% and 64% (P =.04). These data extend the findings of others showing that patients with a low disease burden are more likely to benefit from a second transplantation. Late relapse led to a 10% decrement in LFS beyond the second year after second HCT. This differs from first HCT, in which most relapses occur within 2 years after HCT. [ABSTRACT FROM AUTHOR]

• Granular base material was stabilized by geopolymer, calcium carbide residue (CCR) • CCR was activated by a diluted linear alkyl benzene sulfonic acid (LABSA) • Seven solid/liquid (CCR: diluted LABSA) mixes were prepared and investigated. • Geopolymer of (300/1000) ml LABSA with a (80%:20%) achieved best strength (UCS) • Stabilized aggregate by CCR/LABSA gels produced denser and uniform microstructures. Alkali activated industrial waste/by-product geopolymers have recently gained extensive attention from researchers as a replacement for cement in concrete manufacturing. However, little attention has been given to their employment as a stabilizer of unbound granular base/subbase (UGB) materials in road construction. Stabilizing granular base materials with geopolymers is explored in this study. The investigated geopolymer is composed of calcium carbide residue (CCR), a waste product resulting from the manufacturing of acetylene gas, which activated by a linear alkyl benzene sulfonic acid (LABSA). Four proportions of sulfonic acid dilution ratios and seven solid/liquid (CCR/diluted LABSA) mixes were prepared. The unconfined compressive strength (UCS) of the mixtures was determined in the laboratory. The maximum UCS was achieved by blending a diluted LABSA of (300/1000) ml with a geopolymer (solid: liquid) blend proportion of (80%:20%) by the total weight of aggregate. Based on the results, aggregate mixtures of 2.5%, 5%, 7.5%, and 10% of geopolymer blend content were prepared to determine the maximum UCS value corresponded to the optimum geopolymer mixing ratio. This optimum geopolymer ratio was recommended at 7.5%, which was then exposed to different curing times and environmental conditions to explore the variation in UCS as well as the elastic modulus (E). In addition, Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDX) measurements revealed that the stabilized aggregate contained geopolymer gels generally produced microstructures that are more uniform and denser than the untreated aggregate structure. A blend of CCR and LABSA can be used as a feasible and sustainable eco-friendly alternative as a stabilizing agent for UGB in pavement engineering applications. [ABSTRACT FROM AUTHOR]