In recent decades, several studies have demonstrated the healing capability of bituminous materials, and this property is recognized as an important asset for the development of sustainable road ...pavements. This paper presents a comprehensive summary of various studies concerning healing capability of bituminous materials in order to arrange the relevant topics, evaluation of their results and finding the essential fields for further investigations as a step toward designing sustainable infrastructures. Additionally, there is an attempt to highlight the differences between the real healing and other recoverable phenomena in viscoelastic materials which has been ignored in many studies. In this regard, the mechanism of healing phenomenon, influencing factors (type of bitumen and asphalt mixture, presence of rest periods, temperature and so on.) and the studying methods have been evaluated. Furthermore, the suitability of induction heating technology for enhancing the healing capability as a preventive maintenance approach was discussed. Regarding this subject, the paper proposes a set of recommendations for future studies such as differentiating between the real healing and other recoverable responses of bituminous materials, studying the application of healing in pavement design based on in-depth field experiments, analyzing the effects of additives on the healing capability by considering the chemical monitoring of bitumen, developing a unified laboratory protocol to quantify the healing capability of asphalt mixtures and assessing the applicability of induction heating technology according to long-term impacts.
Different genetic diagnostic and treatment options are used worldwide to improve routine IVF procedures for the benefit of patients. This handbook updates the new genetic diagnostic technologies that ...have been translated to the clinic, aiming to improve outcomes in the clinic and result in a healthy baby in the home. Chapters cover the use of genetic technologies in a personalized manner to unravel the possible genetic risks for the couple wishing to conceive, in terms of sperm, the embryo, the endometrium, miscarriage, and finally the fetus.This expanded new edition covers the range of the latest genetic diagnostic technologies being translated into practice internationally to improve routine IVF procedures for the benefit of patients. Bringing together international experts to discuss their work, this text gives a context for the developments in this very fast-moving area of research and offers a comprehensive and rounded appraisal of hot topics.
•An analysis of elastic elements to improve railway track behavior and durability.•A review of studies about rail pads, under-sleeper pads and under-ballast mats.•The effect of diverse parameters on ...elastic elements behavior is described.•Recommendations about stiffness of elastic elements have been drawn.
Railway is envisaged as the transportation mode of the future, but in spite of its advantages, its development is not exempt from technical difficulties that lead to track deterioration. To overcome these drawbacks, research in this field needs to be developed. Geometry degradation, as well as noise and vibration, have been identified as problems that need to be reduced, which could be possible by modifying track vertical stiffness and obtaining a more homogeneous value along the track. One measure to minimize these problems involves the installation of elastic elements (e.g. rail pads, under-sleeper pads, and under-ballast mats) in the railway track. In fact, this has now become the most effective means to vary track vertical stiffness as well as to abate noise emission and vibrations caused by the passage of trains. This paper discusses the problems associated with track stiffness, geometry degradation, and vibrations, and at the same time, studies the characteristics of elastic elements as well as the research carried out to test and evaluate their effectiveness. After reviewing and analyzing a wide range of research initiatives, this paper proposes a set of recommendations and guidelines for the use of elastic elements in railway infrastructure as well as highlighting a series of possible further investigations.
•We build an LCA-based tool to assess the impact of asphalt pavements.•We assess hot mix asphalt (HMA) and warm mix asphalt (WMA) pavements.•We assess asphalt mixes with various contents of reclaimed ...asphalt pavement (RAP).•We assess uncertainty with Monte Carlo simulations.•Impacts of WMA and HMA are almost equal.•Addition of RAP content decreases the overall impacts.
A comprehensive life cycle assessment of asphalt pavements was conducted including hot mix asphalt (HMA), warm mix asphalt (WMA) with the addition of synthetic zeolites, and asphalt mixes with reclaimed asphalt pavement (RAP). The environmental impacts associated with energy consumption and air emissions were assessed, as well as other environmental impacts resulting from the extraction and processing of minerals, binders and chemical additives; asphalt production; transportation of materials; asphalt paving; road traffic on the pavement; land use; dismantling of the pavement at the end-of-life and its landfill disposal or recycling. Monte Carlo simulations were also conducted to take into account the variability of critical input parameters. Taking into account the entire life cycle, the impacts of zeolite-based WMA pavements were almost equal to the impacts of HMA pavements with the same RAP content. The reduction in the impacts of WMA resulting from the lowering of the manufacturing temperature was offset by the greater impacts of the materials used, especially the impacts of the synthetic zeolites. Moreover, by comparing asphalt mixes with different RAP contents, it was shown that the impacts of asphalt mixes were significantly reduced when RAP was added. All endpoint impacts as well as climate change, fossil depletion and total cumulative energy demand were decreased by 13–14% by adding 15% RAP. A key advantage of WMA is the potentially greater use of RAP. Thus, the decrease in the impacts achieved by adding large amounts of RAP to WMA could turn these asphalt mixes into a good alternative to HMA in environmental terms.
The use of polymer-modified binders in asphalt mixtures has become more widespread due to their reduced thermal susceptibility and improved rutting and fatigue resistance. Nevertheless, their high ...cost limits their application, thus making the use of reclaimed polymers (RP) an interesting alternative for both reducing price and extending the service life of pavements. This paper; therefore, presents a comparative review of the recycled polymers most commonly studied as bitumen modifiers: polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), ethyl vinyl acetate (EVA), and ground tire rubber (GTR), in order to facilitate their selection and extend the use of the bitumen. The differences in terms of melting point, mixing conditions, and maximum quantity of added polymer are analyzed. Moreover, their effect on the mechanical behavior of the asphalt binders and their stability with and without the use of additives is presented. According to the literature revision, the performance of the new binder is more influenced by the kind of polymer that was incorporated and the mixing conditions than by the base bitumen that was chosen, although rheological evaluation is needed to fully understand the modification mechanisms of the modified binder. In general terms, plastomers have a stronger effect in terms of increasing the stiffness of the bitumen in comparison with crumb rubber (elastomers), thus providing an improved rutting resistance. The joint use of polyethylene (plastomer) and crumb rubber (elastomer) can be an interesting option for its recycling potential and mechanical performance, although further study is needed to achieve stable bitumen across the entire range of temperatures; additives, such as maleic anhydride (MA), are commonly employed to improve the stability of the binder and enhance its characteristics, but their use could limit the economic benefits of using recycled materials.
Modern technologies applied to the field of preimplantation genetic diagnosis for aneuploidy screening (PGD-A) have improved the ability to identify the presence of mosaicism. Consequently, new ...questions can now be addressed regarding the potential impact of embryo mosaicism on diagnosis accuracy and the feasibility of considering mosaic embryos for transfer. The frequency of chromosomal mosaicism in products of conception (POCs) of early miscarriages has been reported to be low. Mosaic embryos with an aneuploid inner cell mass are typically lost during the first trimester owing to spontaneous miscarriages. Most of the mosaics in established pregnancies would derive from placental mosaicism or placental aneuploidy, and mosaic embryos with aneuploid inner cell mass should be lost mainly due to first-trimester spontaneous miscarriages. The well described clinical outcomes of live births from mosaic embryos suggest a wide spectrum of phenotypes, from healthy to severely impaired. Therefore, there is a need to balance the risks of discarding a possibly viable embryo with that of transferring an embryo that may ultimately have a lower implantation potential.
A magnetic atom inside a superconductor locally distorts superconductivity. It scatters Cooper pairs as a potential with broken time-reversal symmetry, leading to localized bound states with subgap ...excitation energies, named Shiba states. Most conventional approaches regarding Shiba states treat magnetic impurities as point scatterers with isotropic exchange interaction. Here, we show that the number and the shape of Shiba states are correlated to the spin-polarized atomic orbitals of the impurity, hybridized with the superconductor. Using scanning tunnelling spectroscopy, we spatially map the five Shiba excitations found on subsurface chromium atoms in Pb(111), resolving their particle and hole components. While particle components resemble d orbitals of embedded Cr atoms, hole components differ strongly from them. Density functional theory simulations correlate the orbital shapes to the magnetic ground state of the atom, and identify scattering channels and interactions, all valuable tools for designing atomic-scale superconducting devices.
The emerging field of twistronics, which harnesses the twist angle between two-dimensional materials, represents a promising route for the design of quantum materials, as the twist-angle-induced ...superlattices offer means to control topology and strong correlations. At the small twist limit, and particularly under strain, as atomic relaxation prevails, the emergent moiré superlattice encodes elusive insights into the local interlayer interaction. Here we introduce moiré metrology as a combined experiment-theory framework to probe the stacking energy landscape of bilayer structures at the 0.1 meV/atom scale, outperforming the gold-standard of quantum chemistry. Through studying the shapes of moiré domains with numerous nano-imaging techniques, and correlating with multi-scale modelling, we assess and refine first-principle models for the interlayer interaction. We document the prowess of moiré metrology for three representative twisted systems: bilayer graphene, double bilayer graphene and H-stacked MoSe
/WSe
. Moiré metrology establishes sought after experimental benchmarks for interlayer interaction, thus enabling accurate modelling of twisted multilayers.
The PE-SARD score (syncope, anemia, renal dysfunction) was developed to predict the risk of major bleeding in the acute phase of pulmonary embolism (PE).
We analyzed data from 50,686 patients with ...acute PE included in the RIETE registry to externally validate the PE-SARD score. We calculated the overall reliability of the PE-SARD score, as well as discrimination and calibration for predicting the risk of major bleeding at 30 days. The performance of PE-SARD was compared to the BACS and PE-CH models.
During the first 30 days, 640 patients (1.3 %) had a major bleeding event. The incidence of major bleeding within 30 days was 0.6 % in the PE-SARD-defined low-risk group, 1.5 % in the intermediate-risk group, and 2.5 % in the high-risk group, for an OR of 2.22 (95 % CI, 2.02–2.43) for the intermediate-risk group (vs low-risk group), and 3.94 for the high-risk group (vs low-risk group). The corresponding sensitivity was 81.1 % (intermediate/high vs low risk), and specificity was 85.9 % (95 % CI, 85.8–86.1) (low/intermediate vs high risk). The applicability of PE-SARD was consistent across clinically relevant patient subgroups and over shorter time periods of follow-up (i.e., 3 and 7 days). The C-index was 0.654 and calibration was excellent. The PE-SARD bleeding score improved the major bleeding risk prediction compared with the BACS and PE-CH scores.
The PE-SARD score identifies PE patients with a higher risk of bleeding, which could assist providers for potentially adjusting PE management, in a framework of shared decision-making with individual patients.
•Pulmonary embolism management is associated with an estimated risk of major bleeding of 3.0 %.•In this external validation analysis, the PE-SARD score identified 14.9 % of patients at a four-fold risk of developing major bleeding within the first 30 days of PE with moderate discrimination capacity and excellent calibration capacity.•PE-SARD could potentially assist providers in tailoring management of acute PE in high-bleeding risk patients, in the framework of individualized decision-making.
Eigenstate multifractality is a distinctive feature of noninteracting disordered metals close to a metal–insulator transition, whose properties are expected to extend to superconductivity. While ...multifractality in three dimensions (3D) only develops near the critical point for specific strong-disorder strengths, multifractality in 2D systems is expected to be observable even for weak disorder. Here we provide evidence for multifractal features in the superconducting state of an intrinsic, weakly disordered single-layer NbSe2 by means of low-temperature scanning tunneling microscopy/spectroscopy. The superconducting gap, characterized by its width, depth, and coherence peaks’ amplitude, shows a characteristic spatial modulation coincident with the periodicity of the quasiparticle interference pattern. The strong spatial inhomogeneity of the superconducting gap width, proportional to the local order parameter in the weak-disorder regime, follows a log-normal statistical distribution as well as a power-law decay of the two-point correlation function, in agreement with our theoretical model. Furthermore, the experimental singularity spectrum f(α) shows anomalous scaling behavior typical from 2D weakly disordered systems.
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