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High reclaimed asphalt (RA) renders mixtures more prone to intermediate- and low-temperature cracking failures. In this regard, waste cooking oil (WCO) is gaining attention as rejuvenator to incorporate higher RA in new pavements. Past studies have investigated the rejuvenation effect of WCO irrespective of the variability and source of WCO. This study investigates the variability effect of WCO on the rejuvenation of higher RA. Rheological tests, chemical tests, Fourier transform infrared spectroscopy, and nuclear magnetic resonance were performed on the rejuvenated binders in this study. Further, the rejuvenation index was proposed to assess the rejuvenation capabilities of different WCOs by fitting the Burger model from MSCR data. The findings showed that sunflower oil-based WCO showed the maximum rejuvenation capability, followed by palm and mustard oil-based WCO. Overall, the study highlighted the variability in WCOs considering their rejuvenation capabilities, which may help in selecting appropriate WCOs for rejuvenation.

Higher reclaimed asphalt (RA) usage can lead to cracking in asphalt mixtures. Waste cooking oil (WCO) is recognized as a rejuvenator for incorporating more RA in new pavements. Utilization of higher RA and WCO leads to greater environmental and economic advantages, as both materials are considered as waste. Previous research focused only on the rejuvenating effects of WCO, ignoring the variability of WCO and long-term performance of rejuvenated binder. This study examines the impact of variability of WCO on higher RA rejuvenation, specifically considering blended WCO (BW) to simulate practical conditions, as single source WCO (SSW, mono parental oil) collection is not a practical consideration. Rheological tests, Fourier transform infrared spectroscopy (FTIR), and linear amplitude sweep (LAS) were conducted on the rejuvenated binders. Results show that binders with higher sunflower oil content exhibited the greatest rejuvenation capability, followed by BW with higher palm oil and mustard oil-based WCO, respectively. Moreover, the rejuvenated binders with different BWs exhibited significantly improved fatigue life as compared to conventional binders.

Cold mix asphalt (CMA) has many economic and environmental benefits but its higher moisture susceptibility reduce its use to minor construction and repairing work. To increase the field implementation of CMA, it is very necessary to reduce its moisture susceptibility. So present study examines the effect of lime and cement filler on the moisture susceptibility of CMA. In the study, lime and cement fillers were used in varying proportions i.e. 1% to 5%. Based on volumetric properties and minimum emulsion content criteria, 2% was found to be optimum content for both lime and cement fillers. From Marshall stability, retained Marshall stability, Indirect tensile strength, and Tensile strength ratio values it was found that both fillers considerably improve moisture susceptibility of cold mixes. Energy consumption and cost comparison further concluded that as compared to HMA, incorporation of cement and lime fillers in cold mixes results in economic and environment-friendly mixes.

Only 4% of brief resolved unexplained events (BRUE) are caused by a serious underlying illness. The American Academy of Pediatrics (AAP) guidelines do not distinguish patients who would benefit from further investigation and hospitalization. We aimed to derive and validate a clinical decision rule for predicting the risk of a serious underlying diagnosis or event recurrence.We retrospectively identified infants presenting with a BRUE to 15 children’s hospitals (2015–2020). We used logistic regression in a split-sample to derive and validate a risk prediction model.Of 3283 eligible patients, 565 (17.2%) had a serious underlying diagnosis (n = 150) or a recurrent event (n = 469). The AAP’s higher-risk criteria were met in 91.5% (n = 3005) and predicted a serious diagnosis with 95.3% sensitivity, 8.6% specificity, and an area under the curve of 0.52 (95% confidence interval [CI]: 0.47–0.57). A derived model based on age, previous events, and abnormal medical history demonstrated an area under the curve of 0.64 (95%CI: 0.59–0.70). In contrast to the AAP criteria, patients >60 days were more likely to have a serious underlying diagnosis (odds ratio:1.43, 95%CI: 1.03–1.98, P = .03).Most infants presenting with a BRUE do not have a serious underlying pathology requiring prompt diagnosis. We derived 2 models to predict the risk of a serious diagnosis and event recurrence. A decision support tool based on this model may aid clinicians and caregivers in the discussion on the benefit of diagnostic testing and hospitalization (https://www.mdcalc.com/calc/10400/brief-resolved-unexplained-events-2.0-brue-2.0-criteria-infants).

Proteins involved in proton-/electron-transfer processes often possess “functional” aspartates/aspartic acids (Asp) with variable protonation states. The mechanism of Asp protonation–deprotonation within proteins is unclear. Two questions were asked—the possible types of determinants responsible for Asp protonation–deprotonation and the spatial arrangements of the determinants leading to selective stabilization. The questions were analyzed using nine different solvent models, which scanned the complete protein dielectric range, and four protein models, which illustrated the spatial arrangements around Asp, termed as “molecular association”. The methods employed were quantum chemical calculations and constant pH simulations. The types of the determinants identified were charge–charge interaction, H bonding, dipole−π interaction, extended electronic conjugation, dielectric effect, and solvent accessibility. All solvent-exposed Asp [buried fraction (BF) less than 0.5] were aspartates, and buried Asp were either aspartic acids or aspartates, each having a different “molecular association”. The exposed aspartates were stabilized via a H-bonding network with bulk water, buried aspartates via salt bridge or, minimum, two intramolecular H bonds, and buried aspartic acids via, minimum, one intramolecular H bond. An “acid–alcohol pair” (involving Ser/Thr/Tyr) was a common determinant to any “functional” buried aspartate/aspartic acid. Higher energy “molecular associations” observed within proteins compared to those within water, presumably, indicated easy molecular restructuring and alteration of the Asp protonation states during a protein-mediated proton/electron transfer.

Asphalt binder plays a significant role in the performance of asphalt pavement. However, due to the limited availability of crude oil and the increasing cost of asphalt, alternatives are being investigated. Reclaimed asphalt pavements (RAP) provide a sustainable solution for the increasing demand of asphalt. However, the amount of RAP which can be utilized in asphalt mixtures is limited due to production and performance issues. Incorporation of high RAP content calls for rejuvenators, which rejuvenate the aged binder and increases the degree of blending. Among various rejuvenators, waste cooking oil (WCO) is gaining increased attention due to its availability and concern towards environmental pollution. When combined in proper proportions with RAP, WCO is a potential rejuvenator, which restores the properties of aged binder to that of unaged asphalt binder. This addresses two problems simultaneously and greatly benefit the economy and environment. This study focuses on the viscoelastic and rheological properties of the rejuvenated binder with WCO and RAP. The rheological properties were evaluated using frequency sweep test by assessing the complex shear modulus and rutting parameter of different binders. The viscoelastic properties were studied using multiple stress creep recovery (MSCR) test. The data of the MSCR test was analysed with the Burger model to understand the viscoelastic properties of the rejuvenated RAP binder. For each of 75, 60 and 45% RAP, three different oil proportions were selected, and the optimum WCO content was identified. The study concludes that higher RAP content results in lower viscous strain and higher elastic strain, whereas after mixing of higher WCO, the viscous strain increases, and elastic strain decreases. Hence, it is crucial to mix WCO and RAP in the optimum ratio to obtain the desired rheological and viscoelastic properties.

There has been an increasing use of pediatric procedural sedation and analgesia over the past 20 years, along with numerous medical and technological developments. Sedation can facilitate the smooth completion of otherwise stressful procedures, but it also can be associated with life-threatening complications. Pediatric practitioners need to be familiar with the basic tenets of providing safe and optimal sedation outside the operating room. This review focuses on the current understanding of sedation-related classification, guidelines, and medications, and discusses some special considerations for procedural sedation in common clinical settings. There has been an increasing use of pediatric procedural sedation and analgesia over the past 20 years, along with numerous medical and technological developments. Sedation can facilitate the smooth completion of otherwise stressful procedures, but it also can be associated with life-threatening complications. Pediatric practitioners need to be familiar with the basic tenets of providing safe and optimal sedation outside the operating room. This review focuses on the current understanding of sedation-related classification, guidelines, and medications, and discusses some special considerations for procedural sedation in common clinical settings. [[Pediatr Ann.2018;47(6):e254–e258.]

Recycled asphalt pavement (RAP) and waste cooking oil (WCO) are classes of solid wastes, which have significant environmental implications. Although RAP is being used in asphalt pavements to a certain extent, the usage of high RAP content poses several challenges, which can be addressed by using WCO as a rejuvenator. The optimum combination of two materials will significantly reduce the environmental impact and may address solid waste utilization. This study conducted rheological and chemical investigations on crumb rubber-modified asphalt binder with high RAP content using WCO as a rejuvenator. The crumb rubber-modified binder was chosen in this study as past studies mostly concentrated on unmodified binders. Three concentrations of WCO, such as 5.0, 7.5, and 10% by weight of the total binder, were mixed with the 50 and 60% RAP binder content to find the optimum WCO dose. The rheological tests indicated that asphalt binder with 50% RAP + 5.0% WCO and 60% RAP + 7.5% WCO depicted properties similar to the virgin binder. The fatigue performance of binders with 50 and 60% RAP was significantly better than long-term aged binders. The stripping test of asphalt indicates a slightly higher stripping in binders with RAP compared to the virgin binder. The thermogravimetry analysis revealed the binders had similar thermal stability and mass loss. The Fourier transform infrared spectroscopy (FTIR) indicated a lower presence of aliphatic hydrocarbons and higher aromatics content in the RAP binder modified with WCO. This can be mainly attributed to the peptizing power of WCO.

Common trends in model reduction of large nonlinear finite element (FE)-discretized systems involve Galerkin projection of the governing equations onto a low-dimensional linear subspace. Though this reduces the number of unknowns in the system, the computational cost for obtaining the reduced solution could still be high due to the prohibitive computational costs involved in the evaluation of nonlinear terms. Hyper-reduction methods are then used for fast approximation of these nonlinear terms. In the finite element context, the energy conserving sampling and weighing (ECSW) method has emerged as an effective tool for hyper-reduction of Galerkin-projection-based reduced-order models (ROMs). More recent trends in model reduction involve the use of nonlinear manifolds, which involves projection onto the tangent space of the manifold. While there are many methods to identify such nonlinear manifolds, hyper-reduction techniques to accelerate computation in such ROMs are rare. In this work, we propose an extension to ECSW to allow for hyper-reduction using nonlinear mappings, while retaining its desirable stability and structure-preserving properties. As a proof of concept, the proposed hyper-reduction technique is demonstrated over models of a flat plate and a realistic wing structure, whose dynamics have been shown to evolve over a nonlinear (quadratic) manifold. An online speed-up of over one thousand times relative to the full system has been obtained for the wing structure using the proposed method, which is higher than its linear counterpart using the ECSW.

We present an efficient method to significantly reduce the offline cost associated with the construction of training sets for hyper-reduction of geometrically nonlinear, finite element (FE)-discretized structural dynamics problems. The reduced-order model is obtained by projecting the governing equation onto a basis formed by vibration modes (VMs) and corresponding modal derivatives (MDs), thus avoiding cumbersome manual selection of high-frequency modes to represent nonlinear coupling effects. Cost-effective hyper-reduction is then achieved by lifting inexpensive linear modal transient analysis to a quadratic manifold (QM), constructed with dominant modes and related MDs. The training forces are then computed from the thus-obtained representative displacement sets. In this manner, the need of full simulations required by traditional, proper orthogonal decomposition (POD)-based projection and training is completely avoided. In addition to significantly reducing the offline cost, this technique selects a smaller hyper-reduced mesh as compared to POD-based training and therefore leads to larger online speedups, as well. The proposed method constitutes a solid alternative to direct methods for the construction of the reduced-order model, which suffer from either high intrusiveness into the FE code or expensive offline nonlinear evaluations for the determination of the nonlinear coefficients.