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Dense and narrow rings have been discovered recently around the small Centaur object Chariklo1 and the dwarf planet Haumea2, while being suspected around the Centaur Chiron3, although this point is debated4. They are the first rings observed in the Solar System elsewhere than around giant planets. In contrast to giant planets, gravitational fields of small bodies may exhibit large non-axisymmetric terms that create strong resonances between the spin of the object and the mean motion of ring particles. Here we show that modest topographic features or elongations of Chariklo and Haumea explain why their rings are relatively far away from the central body, when scaled to those of the giant planets5. Resonances actually clear on decadal timescales an initial collisional disk that straddles the corotation resonance (where the particles' mean motion matches the spin rate of the body). Quite generically, the disk material inside the corotation radius migrates onto the body, while the material outside the corotation radius is pushed outside the 1/2 resonance, where the particles complete one revolution while the body completes two rotations. Consequently, the existence of rings around non-axisymmetric bodies requires that the 1/2 resonance resides inside the Roche limit of the body, favouring faster rotators for being surrounded by rings.Chariklo, Haumea and potentially Chiron are the only known ringed Solar System objects that are not giant planets. The rings of these minor bodies are relatively further from their hosts than those around giant planets; this increase is shown to be due to resonances driven by modest topographic features or elongations.

Severe plastic deformation (SPD) is effective in producing bulk ultrafine-grained and nanostructured materials with large densities of lattice defects. This field, also known as NanoSPD, experienced a significant progress within the past two decades. Beside classic SPD methods such as high-pressure torsion, equal-channel angular pressing, accumulative roll-bonding, twist extrusion, and multi-directional forging, various continuous techniques were introduced to produce upscaled samples. Moreover, numerous alloys, glasses, semiconductors, ceramics, polymers, and their composites were processed. The SPD methods were used to synthesize new materials or to stabilize metastable phases with advanced mechanical and functional properties. High strength combined with high ductility, low/room-temperature superplasticity, creep resistance, hydrogen storage, photocatalytic hydrogen production, photocatalytic CO 2 conversion, superconductivity, thermoelectric performance, radiation resistance, corrosion resistance, and biocompatibility are some highlighted properties of SPD-processed materials. This article reviews recent advances in the NanoSPD field and provides a brief history regarding its progress from the ancient times to modernity. Abbreviations: ARB: Accumulative Roll-Bonding; BCC: Body-Centered Cubic; DAC: Diamond Anvil Cell; EBSD: Electron Backscatter Diffraction; ECAP: Equal-Channel Angular Pressing (Extrusion); FCC: Face-Centered Cubic; FEM: Finite Element Method; FSP: Friction Stir Processing; HCP: Hexagonal Close-Packed; HPT: High-Pressure Torsion; HPTT: High-Pressure Tube Twisting; MDF: Multi-Directional (-Axial) Forging; NanoSPD: Nanomaterials by Severe Plastic Deformation; SDAC: Shear (Rotational) Diamond Anvil Cell; SEM: Scanning Electron Microscopy; SMAT: Surface Mechanical Attrition Treatment; SPD: Severe Plastic Deformation; TE: Twist Extrusion; TEM: Transmission Electron Microscopy; UFG: Ultrafine Grained This article comprehensively reviews recent advances on development of ultrafine-grained and nanostructured materials by severe plastic deformation and provides a brief history regarding the progress of this field.

This research compares Fuel Cell Electric Vehicles (FCEVs), Battery Electric Vehicles (BEVs), and Internal Combustion Engine Vehicles (ICEVs) to assess their contribution to the energy transition in Chile. The study evaluates the technical, economic, and environmental aspects of each vehicle type through the total cost of ownership (TCO) and greenhouse gas (GHG) emissions. The methodology involves an analysis of the direct and indirect costs incurred over the vehicle’s lifecycle. This includes the initial purchase cost, fuel and/or energy costs, maintenance and repair expenses, insurance, taxes, and the residual value at the end of the ownership period. These costs are modelled over a defined mileage. The TCO calculation aims to provide a holistic financial perspective, allowing comparisons between vehicle types under consistent economic and operational assumptions. Results show that the minimum TCO is currently achieved with ICEV, followed by BEV and FCEV for trucks and buses, with values of 1.21-1.50, 1.93-1.95, and 2.32-3.0 USD/km for trucks and buses, respectively. By 2050, the TCO for ICEVs is expected to increase by 5.5%-6.2%, while reductions of 44.5-45.5% are projected for BEVs, and 63.8%-64.3% for FCEVs. Results indicate that FCEVs, powered by hydrogen, offer significant advantages in terms of long driving ranges and short refueling times, making them suitable for long-haul and commercial applications. However, challenges related to hydrogen production efficiency, infrastructure development, and high costs per unit of hydrogen remain barriers to widespread adoption. BEVs demonstrate high energy efficiency and zero tailpipe emissions, supported by advances in battery technology and expanding charging infrastructure. They are positioned as the most viable option for urban mobility due to lower operational costs and government incentives. In contrast, ICEVs, while still dominant in the current market, are associated with higher emissions and dependency on fossil fuels, posing challenges to Chile’s sustainability targets. The findings highlight that a diversified approach, combining FCEVs for heavy-duty transport and BEVs for urban areas, could accelerate Chile’s shift towards a sustainable transportation sector. Further research is recommended to explore policy frameworks and investment strategies to address existing infrastructure gaps and enhance the adoption of low-emission vehicle technologies.

This work studies the semiconducting behavior of passive films formed on AISI 316L (UNS S31603) in two different sea-water solutions, non-polluted and polluted, collected from the volcano of El Hierro Island. Polarization measurements, potentiostatic passivation tests, electrochemical impedance spectroscopy, and capacitance measurements were performed. Results show that the polluted seawater worsens passivation kinetics. Additionally, passive films formed on AISI 316L stainless steel in polluted seawater have been found to be less protective than those formed in non-polluted seawater, showing a more defective structure, owing to the acidity of the polluted medium.

Hydrogen and freshwater production can be achieved through microgrids by integrating power generation, electrolyzer, and water purification technologies. An evaluation of a microgrid is conducted to produce hydrogen and freshwater utilizing internal combustion engines (ICE), micro gas turbines (MGT), photovoltaic solar energy (PV), electrolyzers (proton exchange membrane electrolyzer - PEM, and alkaline water electrolysis - AWE), and reverse osmosis (RO), in regions with limited freshwater resources and high solar irradiation. The methodology involves modelling and assessing the systems connected to the microgrid to determine hourly production, the levelized costs of electricity (LCOE), hydrogen (LCOH), and water (LCOW) across different configurations and zones, and the environmental impact of this integrated system. A sensitivity analysis is performed on the key variables such as investment costs and fuel prices. The results indicate that microgrids offer significant potential for enhancing energy and water sustainability, providing a viable solution for regions with abundant solar energy but scarce freshwater resources. The optimal configuration includes an ICE, PV, RO, and AWE system, yielding levelized costs of 184.9 USD/MWh, 9.71 USD/kg H 2 , and 1.68 USD/m H 2 O in Pisagua. In contrast, a PV, RO, and AWE system achieves significantly lower costs of 60.9 USD/MWh, 5.1 USD/kg H 2 , and 0.98 USD/m H 2 O at the same location. This integrated approach optimally balances energy production, water desalination, and cost-effectiveness, offering a resilient and sustainable solution for remote and arid regions. Further research is recommended to address scalability challenges and improve system resilience under varying environmental conditions.

Severe mechanical processing routes based on high-energy ball milling (HEBM) or severe plastic deformation (SPD) can be used to produce Mg nanomaterials for hydrogen storage applications. In the last few years, we have been exploring in our research group different SPD processing routes in Mg systems to achieve good activation (first hydrogenation) and fast H-absorption/desorption kinetics, combined with enhanced air resistance. In this paper, we compare SPD techniques applied to Mg with HEBM applied to MgH2. Both advanced – melt spinning (MS), high-pressure torsion (HPT) – and more conventional – cold rolling (CR), cold forging (CF)- techniques are evaluated as means of production of bulk samples with very refined microstructures and controlled textures. In the best SPD processing conditions, attractive H-absorption/desorption kinetic properties are obtained, which are comparable to the ones of MgH2 milled powders, even if the needed temperatures are higher – 350°C compared to 300°C.CR and CF stand out as the processes with higher potential for industrial application, considering the level of the attained hydrogen storage properties, its simplicity and low cost.

Objectives Chronic kidney disease (CKD) unrelated to conventional risk factors occurs in Central America, mostly in younger, male agricultural workers. We explored residence and occupation at different altitudes in El Salvador as surrogates for heat stress. Methods In a population-based survey we determined prevalences of elevated serum creatinine (S-Cr) (≥1,2 and 0.9 mg/dl in males and females), CKD ≥ stage 3 (glomerular filtration rate <60 ml/min/1.73 m2) and proteinuria among occupational subgroups of the populations age 20–60 of five Salvadorian communities, together 256 men and 408 women (participation 73%). Logistic regressions assessed associations between kidney function and agricultural occupations by altitude and sex, adjusting for conventional risk factors. Results Among men of the coastal communities with current sugarcane and past cotton production, 30% had elevated S-Cr and 19% CDK ≥ stage 3 compared to 4% and 1% in the communities above 500 m with sugarcane, coffee and service-oriented economies. Prevalence of elevated S-Cr among male sugarcane and cotton workers in the coastal lowlands with extremely hard and hot working conditions was 33% vs 4% among sugarcane farmers at 500 m (approximately 4oC lower) and 4% among subsistence farmers. Women followed a weaker but similar pattern. For 10-year increments in coastal sugarcane or cotton plantation work, the occurrence of elevated S-Cr tripled among men and doubled among women. Proteinuria was infrequent and of low grade indicating tubulointerstitial nephropathy. Conclusions Agricultural work on lowland sugarcane and cotton plantations was associated with CKD among men and women, possibly related to strenuous and hot work with repeated dehydration.

The standard pathways of testing and treatment for hepatitis C virus (HCV) infection in tertiary healthcare are not easily accessed by people who inject drugs (PWID). The aim of this study was to evaluate the efficacy of integrated treatment of chronic HCV infection among PWID. INTRO-HCV is a multicenter, randomized controlled clinical trial. Participants recruited from opioid agonist therapy (OAT) and community care clinics in Norway over 2017 to 2019 were randomly 1:1 assigned to the 2 treatment approaches. Integrated treatment was delivered by multidisciplinary teams at opioid agonist treatment clinics or community care centers (CCCs) for people with substance use disorders. This included on-site testing for HCV, liver fibrosis assessment, counseling, treatment, and posttreatment follow-up. Standard treatment was delivered in hospital outpatient clinics. Oral direct-acting antiviral (DAA) medications were administered in both arms. The study was not completely blinded. The primary outcomes were time-to-treatment initiation and sustained virologic response (SVR), defined as undetectable HCV RNA 12 weeks after treatment completion, analyzed with intention to treat, and presented as hazard ratio (HR) and odds ratio (OR) with 95% confidence intervals. Integrated treatment for HCV in PWID was superior to standard treatment in terms of time-to-treatment initiation, and subsequently, more people achieved SVR. Among those who initiated treatment, the SVR rates were comparable. Scaling up of integrated treatment models could be an important tool for elimination of HCV.

To evaluate the effect of soil chemical properties on the crop yield of corn, in the context of site-specific fertilization, we characterized the spatio-temporal variability of these properties and crop yield in a lot at the Centro Agropecuario Marengo of the Universidad Nacional de Colombia (Mosquera, Colombia). Using a systematic sampling grid of 32 points (25 x 25 m), soil samples were taken before crop sowing and 60 days after sowing (das) to determine soil pH, N (%); Ca, K, Mg, Na, Al, H (cmol+ kg-1), P, Cu, Fe, Mn, Zn and B (mg kg-1). At 162 das, harvest and yield components were evaluated by site. The data was processed using multivariate procedures, descriptive analysis and geostatistical analysis. Emergent properties were obtained from the original chemical variables using principal component analysis (PCA); these new variables were evaluated using geostatistical analysis to show spatial distribution and its correlation with performance. The PCA allowed the finding of three patterns of spatial variability in the soil corresponding to the variables related to soil fertility CO, Ca, Mg, K, CIC and B, the availability of nutrients by soil redox potential, and the variability associated with salinity explained by the Na content and soil electrical conductivity. The first group of variables largely explains the spatial variability of crop yield of corn. Key words: fertilization, geostatistical analysis, productivity, soil Para evaluar el efecto de las propiedades químicas del suelo sobre el rendimiento del cultivo del maíz para choclo, en el contexto de la fertilización específica por sitio, se caracterizó la variabilidad espacio temporal de esas propiedades y del rendimiento del cultivo, en un lote del Centro Agropecuario Marengo de la Universidad Nacional de Colombia (Mosquera, Colombia). Usando una red sistemática de muestreo de 32 puntos (25 x 25 m), referenciados dentro del lote, antes de siembra del cultivo y 60 días después de siembra (dds), se tomaron muestras de suelos para determinar pH; N (%); Ca, K, Mg, Na, Al, H (cmol+ kg-1); P, Cu, Fe, Mn, Zn y B (mg kg-1). A los 162 dds se evaluó la cosecha y los componentes de rendimiento por punto. El procesamiento de los datos se realizó mediante procedimientos multivariados, análisis descriptivos y análisis geoestadísticos. Se obtuvieron propiedades emergentes a partir de las variables químicas originales mediante análisis de componentes principales (ACP); a esas nuevas variables se les realizó análisis geoestadístico para conocer su distribución espacial y su correlación con el rendimiento. El ACP permitió encontrar tres patrones de variabilidad espacial en el suelo y que corresponden a: las variables relacionadas con la fertilidad del suelo CO, Ca, Mg, K, CIC y B; la disponibilidad de nutrientes por potencial redox del suelo; y, la variabilidad relacionada con la salinidad explicada por el contenido de Na y conductividad eléctrica del suelo. El primer grupo de variables explicó en gran medida la variabilidad espacial del rendimiento del cultivo del maíz.Palabras clave: fertilización, análisis geoestadístico, productividad, suelo.