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This paper performs an in-depth study of the theoretical basis behind the strong discontinuity methods to improve local fracture simulations using the Embedded Finite Element Method (E-FEM). The process starts from a review of the elemental enhancement functions found in current E-FEM literature, providing the reader a solid context of E-FEM fundamentals. A set of theoretical pathologies is then discussed, which prevent current frameworks from attaining full kinematic consistency and introduce unintended mesh dependencies. Based on this analysis, a new proposal of strong discontinuity enhancement functions is presented considering generalised fracture kinematics in a full tridimensional setting and a more robust definition of internal auxiliary functions. Element-level simulations are performed to compare the outputs within a group of selected E-FEM approaches, including the novel proposal. Simulations show that the new element formulation grants a wider level of basic kinematic coherence between the local fracture outputs and element kinematics, demonstrating an increase in robustness that might drive the usefulness of E-FEM techniques for fracture simulations to a higher level.

Silicon photonics is playing a key role in areas as diverse as high-speed optical communications, neural networks, supercomputing, quantum photonics, and sensing, which demand the development of highly efficient and compact light-processing devices. The lithographic segmentation of silicon waveguides at the subwavelength scale enables the synthesis of artificial materials that significantly expand the design space in silicon photonics. The optical properties of these metamaterials can be controlled by a judicious design of the subwavelength grating geometry, enhancing the performance of nanostructured devices without jeopardizing ease of fabrication and dense integration. Recently, the anisotropic nature of subwavelength gratings has begun to be exploited, yielding unprecedented capabilities and performance such as ultrabroadband behavior, engineered modal confinement, and sophisticated polarization management. Here we provide a comprehensive review of the field of subwavelength metamaterials and their applications in silicon photonics. We first provide an in-depth analysis of how the subwavelength geometry synthesizes the metamaterial and give insight into how properties like refractive index or anisotropy can be tailored. The latest applications are then reviewed in detail, with a clear focus on how subwavelength structures improve device performance. Finally, we illustrate the design of two ground-breaking devices in more detail and discuss the prospects of subwavelength gratings as a tool for the advancement of silicon photonics.

Mesoporous silica nanoparticles (MSNs) are frequently functionalized to be used for specific applications, including catalysis and biomedical engineering. In this research, MCM-41-MSNs were synthesized by the sol–gel method and were functionalized with different quantities of (3-aminopropyl) triethoxysilane (APTES) using a post-grafting method to determine the physicochemical and structural changes in the MSNs. The functionalized materials were assessed by different characterization techniques, namely, TGA, FTIR, BET, SEM, TEM, DLS, zeta potential, SAXS, XRD and XPS. The FTIR data confirmed the presence of amino groups on the MSN surfaces, and the results from the XPS, TGA and zeta potential demonstrated that the APTES concentration during post-grafting directly affects the quantity of amino groups bound to the MSNs. The SAXS, TEM and nitrogen adsorption–desorption analyses showed that as the amount of APTES in the MSNs increases, the mesoporous structure become more disordered. Graphical Abstract

Spectral filters are fundamental building blocks in integrated photonics. Bragg grating filters have been demonstrated in silicon waveguides with a wide range of spectral responses and are suitable for wavelength division multiplexing applications. However, retrieving Bragg grating reflections typically requires external components such as fiber optic circulators. In this work, we develop fully integrated add-drop filters based on cladding-modulated Bragg gratings incorporated in a Mach–Zehnder interferometer configuration. We design complex spectral filtering devices with single and dual-band flat-top responses for the specified bandwidth. Additionally, we propose a novel design methodology which aims to minimize phase errors within the filters. We experimentally demonstrate add-drop filters with single-band and two-band rejection spectra at the datacom O-band, fabricated on a 220-nm thick silicon-on-insulator platform. Our results show an insertion loss below 1 dB and a crosstalk of around −20 dB at the channel center for a 4.5-nm wavelength grid and 3-nm wide channels.

PurposeThe aim of this study was to determine whether MRI texture analysis could predict the prognosis of patients with non-specific chronic low back pain.MethodsA prospective observational study was conducted on 100 patients with non-specific chronic low back pain, who underwent a conventional MRI, followed by rehabilitation treatment, and revisited after 6 months. Sociodemographic variables, numeric pain scale (NPS) value, and the degree of disability as measured by the Roland–Morris disability questionnaire (RMDQ), were collected. The MRI analysis included segmentation of regions of interest (vertebral endplates and intervertebral disks from L3–L4 to L5–S1, paravertebral musculature at the L4–L5 space) to extract texture variables (PyRadiomics software). The classification random forest algorithm was applied to identify individuals who would improve less than 30% in the NPS or would score more than 4 in the RMDQ at the end of the follow-up. Sensitivity, specificity, and the area under the ROC curve were calculated.ResultsThe final series included 94 patients. The predictive model for classifying patients whose pain did not improve by 30% or more offered a sensitivity of 0.86, specificity 0.57, and area under the ROC curve 0.71. The predictive model for classifying patients with a RMDQ score 4 or more offered a sensitivity of 0.83, specificity of 0.20, and area under the ROC curve of 0.52.ConclusionThe texture analysis of lumbar MRI could help identify patients who are more likely to improve their non-specific chronic low back pain through rehabilitation programs, allowing a personalized therapeutic plan to be established.

Edward Buckler, Sarah Hearne and colleagues integrate two approaches to characterize the genetic diversity of a large number of geographically distributed maize landraces. They examine flowering time and adaptation to altitude and find that the majority of the associated SNPs overlap both traits. Landraces (traditional varieties) of domesticated species preserve useful genetic variation, yet they remain untapped due to the genetic linkage between the few useful alleles and hundreds of undesirable alleles 1 . We integrated two approaches to characterize the diversity of 4,471 maize landraces. First, we mapped genomic regions controlling latitudinal and altitudinal adaptation and identified 1,498 genes. Second, we used F-one association mapping (FOAM) to map the genes that control flowering time, across 22 environments, and identified 1,005 genes. In total, we found that 61.4% of the single-nucleotide polymorphisms (SNPs) associated with altitude were also associated with flowering time. More than half of the SNPs associated with altitude were within large structural variants (inversions, centromeres and pericentromeric regions). The combined mapping results indicate that although floral regulatory network genes contribute substantially to field variation, over 90% of the contributing genes probably have indirect effects. Our dual strategy can be used to harness the landrace diversity of plants and animals.

The 2030 Climate target plan of the European Commission (EC) establishes a greenhouse gases (GHG) emissions reduction target of at least 55% by 2030, compared to 1990. It highlights that all transport modes—road, rail, aviation and waterborne—will have to contribute to this aim. A smart combination of vehicle/vessel/aircraft efficiency improvements, as well as fuel mix changes, are among the measures that can reduce GHG emissions, reducing at the same time noise pollution and improving air quality. This research provides a comprehensive analysis of recent research and innovation in low-emission alternative energy for transport (excluding hydrogen) in selected European Union (EU)-funded projects. It considers the latest developments in the field, identifying relevant researched technologies by fuel type and their development phase. The results show that liquefied natural gas (LNG) refueling stations, followed by biofuels for road transport and alternative aviation fuels, are among the researched technologies with the highest investments. Methane-based fuels (e.g., compressed natural gas (CNG), LNG) have received the greatest attention concerning the number of projects and the level of funding. By contrast, liquefied petroleum gas (LPG) only has four ongoing projects. Alcohols, esters and ethers, and synthetic paraffinic and aromatic fuels (SPF) are in between. So far, road transport has the highest use of alternative fuels in the transport sector. Despite the financial support from the EU, advances have yet to materialize, suggesting that EU transport decarbonization policies should not consider a radical or sudden change, and therefore, transition periods are critical. It is also noteworthy that there is no silver bullet solution to decarbonization and thus the right use of the various alternative fuels available will be key.

Several gender differences exist in the transport sector. These include accessibility to transport modes, safety and security when travelling, and the participation of women in transport research and innovation (R&I). In order to achieve sustainable and inclusive transport, planners and policymakers should consider all impacts on gender equality. This paper sheds light on two main issues which interconnect through the decision-making process. The first relates to women’s behaviour in the transport system (i.e., studies the gender mobility gap). The second concerns the role of women in transport R&I, particularly the topics covered by research projects and relevant descriptive statistics of their participation in the sector. Based on a literature review, this paper identifies critical issues in the European transport sector and key European Union policy initiatives and regulations that address gender equality and transport. The European Commission’s Transport Research and Innovation Monitoring and Information System (TRIMIS) is used to summarise the status and evolution of European research in addressing women’s issues in transport. It also analyses the participation of women in European transport research and innovation activities. The paper assesses progress to date and identifies challenges and opportunities for women, mobility, and transport. It concludes by providing policy recommendations to overcome the major barriers to gender equality in the European transport sector and to transport research and innovation.

The Cerro Prieto basin, a tectonically active pull-apart basin, hosts significant geothermal resources currently being exploited in the Cerro Prieto Geothermal Field (CPGF). Consequently, natural tectonic processes and anthropogenic activities contribute to three-dimensional surface displacements in this pull-apart basin. Here, we obtained the Cerro Prieto Step-Over 3D surface velocity field (3DSVF) by accomplishing a weighted least square algorithm inversion from geometrically quasi-orthogonal airborne UAVSAR and RADARSAT-2, Sentinel 1A satellite Synthetic Aperture-Radar (SAR) imagery collected from 2012 to 2016. The 3DSVF results show a vertical rate of 150 mm/yr and 40 mm/yr for the horizontal rate, where for the first time, the north component displacement is achieved by using only the Interferometric SAR time series in the CPGF. Data integration and validation between the 3DSVF and ground-based measurements such as continuous GPS time series and precise leveling data were achieved. Correlating the findings with recent geothermal energy production revealed a subsidence rate slowdown that aligns with the CPGF’s annual vapor production.

Societal Impact Statement The conflict between Ukraine and Russia will negatively affect not only food security but also food safety. Crops produced in Ukraine and Russia are at little risk of contamination by mycotoxins such as aflatoxin. However, due to the conflict, wheat, maize, sunflower, and other crops that would have been produced in and exported from Ukraine will need to be produced somewhere else. If done in warm production areas, strategies will need to be implemented to prevent mycotoxin contamination, which has negative health, social, and economic impacts. Summary Conflicts across the globe affect food security and also have a heavy toll on food safety. Many of the areas affected by conflict are breadbaskets for multiple countries. When the production of staple crops is compromised by diverse conflicts, it becomes necessary to grow them somewhere else to satisfy local, regional, and/or international requirements. However, if that production is done in tropical and subtropical zones, it must be done incorporating strategies to prevent mycotoxin contamination, which has negative health, social, and economic impacts. Otherwise, increased production of susceptible crops in mycotoxin‐prone areas may augment the already occurring negative impacts, which are severe in the global south. El conflicto entre Ucrania y Rusia afectará negativamente no solo la seguridad alimentaria sino también la inocuidad alimentaria. Los cultivos producidos en Ucrania y Rusia tienen poco riesgo de contaminación por micotoxinas como las aflatoxinas. Sin embargo, debido al conflicto, el trigo, el maíz, el girasol y otros cultivos que se habrían producido y exportado desde Ucrania deberán producirse en otros lugares. Si esa producción se lleva a cabo en zonas cálidas y húmedas, será necesario implementar estrategias para prevenir la contaminación por micotoxinas, la cual tiene impactos negativos en la salud, la sociedad, y la economía. Le conflit entre l'Ukraine et la Russie affectera non seulement la sécurité alimentaire, mais aussi qualité des aliments. Les denrées alimentaires produites en Ukraine et en Russie présentent peu de risques de contamination par les mycotoxines telle que l'aflatoxine. Cependant, en raison du conflit, le blé, le maïs, le tournesol et d'autres denrées qui auraient été produits et exportés d'Ukraine vont être relocalisés ailleurs. Ainsi, si les cultures se font dans des zones chaudes et humides, des stratégies devront être mises en œuvre pour prévenir la contamination par les mycotoxines, qui affecte la santé humaine et animal, et a un impact socio‐économie important. The conflict between Ukraine and Russia will negatively affect not only food security but also food safety. Crops produced in Ukraine and Russia are at little risk of contamination by mycotoxins such as aflatoxin. However, due to the conflict, wheat, maize, sunflower, and other crops that would have been produced in and exported from Ukraine will need to be produced somewhere else. If done in warm production areas, strategies will need to be implemented to prevent mycotoxin contamination, which has negative health, social, and economic impacts.